,1, 柳开楼2,4, 韩天富2, 张会民,2Spatio-Temporal Variations of Soil Organic Matter in Paddy Soil and Its Driving Factors in China
LI DongChu1,2, HUANG Jing2, MA ChangBao3, XUE YanDong3, GAO JuSheng2, WANG BoRen2, ZHANG YangZhu,1, LIU KaiLou2,4, HAN TianFu2, ZHANG HuiMin,2通讯作者:
责任编辑: 李云霞
收稿日期:2019-08-26网络出版日期:2020-06-16
| 基金资助: |
Received:2019-08-26Online:2020-06-16
作者简介 About authors
李冬初,lidongchu@caas.cn。
摘要
关键词：
Abstract
Keywords：
PDF (642KB)元数据多维度评价相关文章导出EndNote|Ris|Bibtex收藏本文
本文引用格式
李冬初, 黄晶, 马常宝, 薛彦东, 高菊生, 王伯仁, 张杨珠, 柳开楼, 韩天富, 张会民. 中国稻田土壤有机质时空变化及其驱动因素[J]. 中国农业科学, 2020, 53(12): 2410-2422 doi:10.3864/j.issn.0578-1752.2020.12.009
LI DongChu, HUANG Jing, MA ChangBao, XUE YanDong, GAO JuSheng, WANG BoRen, ZHANG YangZhu, LIU KaiLou, HAN TianFu, ZHANG HuiMin.
0 引言
【研究意义】土壤有机质与土壤质量密切相关,有机质数量的耗竭和质量的恶化可直接导致土壤生态功能的衰退[1]。土壤有机质的变化受多种因素的影响,具有较强的时空变异性[2,3,4]。水稻土是中国面积最大、分布最广的耕地土壤,占全国耕地面积的1/5,维持稻田土壤质量和生态功能对我国粮食生产和安全至关重要[5,6]。研究稻田土壤有机质变化对全面了解我国稻田合理施肥以及保障作物高产稳产具有重要指导意义。【前人研究进展】土壤有机质变化方面已开展了较多研究,包括国家尺度、省域尺度,以及典型地区和气候带,土壤类型区等方面。黄耀等基于1980—2000年文献数据的研究表明,全国近60%的农田表层土壤有机质含量上升,有机碳储量总体增加310—400 Tg,其中水稻土和潮土有机质含量增加明显[3]。杨帆等比较测土施肥和全国第二次土壤普查数据,结果表明近30年全国农田耕层土壤有机质提高4.85 g·kg-1,并指出我国农田有机质上升原因可能包括秸秆还田、农作物产量的快速提升、免耕少耕技术推广以及堆肥和绿肥的施用等[4]。TANG等通过14 371个野外监测点,估算出全国陆地生态系统不同土地利用方式碳库特征,认为其与年均气温和降水关系显著,并指出82.9%的碳库存在于0—1 m的土层中[7]。PAN等[8]通过比较国家耕地土壤监测数据和全国第二次土壤普查数据,研究表明全国稻田表层土壤有机碳密度显著高于旱地,其固碳潜力巨大层中。顾成军等分别在不同省域尺度上研究土壤有机质变化特征,认为不同土地利用方式,肥料的大量施用,秸秆还田及其土壤类型等显著影响土壤有机质含量[9,10,11,12,13,14,15,16]。杨玉盛等分别分析了中亚热带山区、黄土丘陵沟壑区、东北黑土区等地带性土壤有机质变化特征,表明不同土地利用方式、土壤类型、土壤覆盖、土壤坡度等影响土壤有机质含量[17,18,19]。任丽等报道了苹果、柑橘等果树种植区土壤有机质空间分布及其影响因素,并建立了相关模型[20,21]。此外还有较多关于不同点位上的土壤有机质变化研究,多数报道施用有机肥显著提升土壤有机质含量,常规施肥土壤有机质含量呈上升趋势[22,23,24]。在有机质变化的研究手段上有基于多点位的统计学比较分析[3-4, 6-10],也有基于地统计学方法及GIS技术的时空变异特征分析[12,25],以及模型分析[11, 26-27]。目前,研究较多集中在对土壤有机质驱动因子的探讨,以及土壤有机质结构、形态及功能等研究[28,29,30,31]。【本研究切入点】目前国家尺度的农田土壤有机质含量变化研究一方面基于布置在全国各地的长期定位试验点。比如中国农业科学院的肥力与肥料效应监测网长期定位试验[32],中国科学院CERN台站长期定位试验,以及各地农业科学院系统布置的大量长期定位试验,其研究多基于不同施肥、轮作、耕作等对土壤有机质的影响[22]。另一方面,基于区域尺度上的采样数据或者文献调研数据,通过与第二次土壤普查数据比较,或者通过模型模拟获取全国农田土壤有机质含量变化[3, 8]。农业农村部自1988年开始建立国家级耕地质量监测点,其中在中国主要水稻种植区稻田土壤上布置了大量的长期定位监测点。李建军等依托国家耕地质量1988—2012年数据研究了中国稻田土壤基础地力变化特征和长江中下游稻田土壤养分变化特征,结果表明中国稻田土壤基础地力总体呈上升趋势,基础地力与水稻产量同步上升。长江中下游稻田土壤养分含量基本呈上升趋势,土壤肥力总体改善[33,34]。韩天富等依托国家耕地质量1988—2017年数据研究认为施肥尤其是有机肥与无机肥配合施用是维持和提高水稻高产的重要措施[35]。近年来,我国农业结构调整,尤其是种植结构优化和有机替代,化肥减施增效等政策密集影响,土壤面临更加复杂的作物、肥料投入和气候变化。另一方面,基于国家级耕地质量监测点的全国稻田土壤有机质长期、动态、定位等的系统研究和分析相对较少,其变化特征、速率和趋势不明确。【拟解决的关键问题】本研究拟依托338个国家级稻田土壤长期定位监测点,系统分析中国主要水稻种植区稻田土壤有机质变化特征,旨在揭示我国稻田土壤有机质演变规律及区域分异特征,分析稻田土壤有机质变化驱动因素。评价土壤有机质对土壤容重和耕层深度等影响,为稻田土壤合理施肥和作物稳产高效提供科学指导,为耕地地力提升和建设高质量稻田提供科学依据。1 材料与方法
1.1 监测点分布概况
基于农业农村部在全国不同稻作区布置的土壤监测点及其数据库[35],选取全国水稻种植区域稻田土壤监测点共338个,根据水稻监测点分省（区）分布情况,结合自然地理区域,本研究监测点位按照数量高低,分布于长江中游（111个）,长江下游（82个）,华南（80个）,西南（47个）,东北（18个）。在全国稻田总的338个土壤监测点中,有140个为长期定位监测点,其中长江中游、长江下游、华南、西南和东北分别有52个、29个、31个、22个和6个。全国稻田土壤长期监测点自1988年开始监测,分别设置无肥对照区和常规施肥区（农民习惯施肥）两个处理。种植制度根据不同区域气候特点分别包括①东北,一年一熟制,种植水稻为主;②长江中游,一年两熟制,种植制度主要为双季稻,部分为水稻-油菜（小麦、烟叶、蔬菜、绿肥等）轮作;③长江下游,一年两熟制,以水稻-小麦（油菜、绿肥等）水旱轮作为主;④西南,一年两熟制,以水稻-小麦（油菜、玉米、冬闲等）水旱轮作为主;⑤华南,一年两熟制（部分三熟制）,种植制度主要为双季稻,部分为水稻-蔬菜（烟叶、绿肥等）轮作。各点分别监测肥料养分氮磷钾投入、主要作物产量以及土壤肥力状况。
1.2 样品采集与分析
各监测点按照统一的规范,分别于每年度最后一季作物收获后采集耕层土壤样品。耕层指农业耕作、施肥、灌溉影响区域和作物根系分布的集中层段,其颜色、结构、紧实度都有明显的特征和界线。每个处理采用“S”型采集5—10钻土壤样品,3次重复。土壤样品自然风干,人工除去植物残体和石块后过2 mm 筛,混匀后备用。土壤各指标测定方法依据《土壤分析技术规范》[36]。各监测点每年记录施肥种类、数量,作物籽粒和秸秆产量以及管理措施等,现场根据作物根系分布和土壤颜色、紧实度等指标调查耕层厚度。1.3 数据处理与统计分析
各稻作区监测点位数量及其代表面积不同,本文利用各省（区）稻田土壤有机质含量的平均值与该省稻田土壤面积比例加权平均后得到各稻作区土壤有机质平均含量[37,38]。式中,SOM为稻作区土壤有机质平均含量（g·kg-1）;Mi为该区域i省份土壤有机质平均含量（g·kg-1）,Ai为i省份稻作土壤面积（104 hm2）。
各点数据采用Excel 2016整理计算,运用SigmaPlot 12.0分析并作图,IBM SPSS 22.0进行差异显著性检验（LSD,Duncan (D),P<0.05）。
2 结果
2.1 土壤有机质含量空间变化
全国稻田耕层土壤有机质平均含量32.4 g·kg-1,变幅在11.3—65.0 g·kg-1（表1）。其中湖南、云南、贵州、广西、广东、江西、黑龙江、吉林、浙江和福建等10省（区）稻田耕层土壤有机质平均含量在30.0 g·kg-1以上。安徽、海南和上海低于25.0 g·kg-1。各稻作区域耕层土壤有机质平均含量高低顺序为长江中游35.1 g·kg-1、华南34.2 g·kg-1、东北33.6 g·kg-1、西南31.0 g·kg-1和长江下游26.3 g·kg-1。由图1可知,根据箱线图统计的各稻作区耕层土壤有机质含量置信区间分别为长江中游20.6—51.2 g·kg-1,华南15.2—48.6 g·kg-1,东北11.9—51.6 g·kg-1,西南18.1—45.4 g·kg-1和长江下游17.2—43.9 g·kg-1。各稻作区稻田耕层土壤有机质含量差异显著。长江中游地区耕层土壤有机质含量显著高于西南地区和长江下游地区（P<0.05）。从经度分布来看,各区域稻田耕层土壤有机质含量无显著差异。从纬度分布看,N25°—30°和N20°—25°区域稻田耕层土壤有机质含量显著高于<N20°和N30°—40°区域（P<0.05）。Table 1
表1
表1不同区域稻田耕层土壤有机质平均含量
Table 1
| 稻作区域 Rice cultivation region | 省份 Province | 水稻种植面积 Rice cultivation area (×104 hm2) | 有机质含量 SOM content (g·kg-1) | 样本数 No. of samples | |||
|---|---|---|---|---|---|---|---|
| 平均含量 SOM | 最低含量 Min. | 最高含量 Max | 中位数 Median | ||||
| 东北NE | 黑龙江Heilongjiang | 394.9 | 34.4 | 30.0 | 39.5 | 34.1 | 4 |
| 吉林Jilin | 82.1 | 34.1 | 26.7 | 51.6 | 33.1 | 6 | |
| 辽宁Liaoning | 49.3 | 26.3 | 11.9 | 30.2 | 26.4 | 8 | |
| 平均 Mean | 526.2 | 33.6 | 11.9 | 51.6 | 30.1 | 18 | |
| 长江中游MYR | 湖北Hubei | 236.8 | 29.1 | 17.7 | 41.1 | 27.9 | 19 |
| 湖南Hunan | 423.9 | 38.7 | 16.9 | 65.0 | 36.7 | 41 | |
| 江西Jiangxi | 350.5 | 34.7 | 16.5 | 50.9 | 34.7 | 51 | |
| 平均 Mean | 1011.2 | 35.1 | 16.5 | 65.0 | 33.7 | 111 | |
| 长江下游LYR | 安徽Anhui | 260.5 | 24.5 | 13.1 | 38.1 | 26.3 | 29 |
| 江苏Jiangsu | 223.8 | 26.0 | 16.6 | 39.7 | 25.0 | 37 | |
| 上海Shanghai | 10.4 | 22.9 | 20.0 | 25.8 | 22.9 | 2 | |
| 浙江Zhejiang | 78.4 | 33.4 | 13.7 | 63.8 | 37.3 | 14 | |
| 平均Mean | 573.1 | 26.3 | 13.1 | 63.8 | 26.3 | 82 | |
| 西南SW | 贵州Guizhou | 67.8 | 37.3 | 35.4 | 40.8 | 37.0 | 3 |
| 四川Sichuan | 187.5 | 26.1 | 17.3 | 44.2 | 25.1 | 29 | |
| 云南Yunnan | 87.1 | 38.0 | 26.2 | 50.2 | 33.0 | 7 | |
| 重庆Chongqing | 65.9 | 29.0 | 23.8 | 36.0 | 29.8 | 8 | |
| 平均Mean | 408.2 | 31.0 | 17.3 | 50.2 | 29.5 | 47 | |
| 华南SC | 福建Fujian | 76.9 | 30.1 | 20.9 | 40.0 | 29.3 | 14 |
| 广东Guangdong | 180.5 | 35.3 | 15.2 | 51.3 | 32.3 | 35 | |
| 广西Guangxi | 152.7 | 36.4 | 13.4 | 56.3 | 33.9 | 13 | |
| 海南Hainan | 18.0 | 22.9 | 11.3 | 33.4 | 23.5 | 18 | |
| 平均Mean | 428.2 | 34.2 | 11.3 | 56.3 | 29.0 | 80 | |
| 全国National | 2946.9 | 32.4 | 11.3 | 65.0 | 29.4 | 338 | |
新窗口打开|下载CSV
图1
新窗口打开|下载原图ZIP|生成PPT图1不同区域稻田耕层土壤有机质含量及随经度和纬度变化
箱式图内中间实线、虚线以及箱体的下边缘线、上边缘线、下误差线、上误差线分别表示中值、平均值、第25、75、5、95 百分位数。不同大写字母表示不同区域差异显著（P<0.05）。下同
Fig. 1The SOM content of paddy soil in different rice cultivation regions and different regions with longitude and latitude
Solid line and dotted line, lower edge and upper edge, bars represent median and mean values, 25th and 75th, 5th and 95th percentiles of all data, respectively. Capital letter indicates the difference significance among different regions at the 0.05 level. The same as below
2.2 土壤有机质含量的时间变化
2.2.1 全国稻田土壤有机质含量的时间变化 全国140个长期监测点结果表明,常规施肥条件下近30年全国稻田耕层土壤有机质含量总体呈现上升趋势（图2-a）。通过对所有监测点338个点位数据土壤有机质含量的统计,与1988年相比,近30年全国稻田耕层土壤有机质平均含量上升3.49 g·kg-1（图2-b）。回归方程表明稻田耕层土壤有机质年增加速率0.09—0.12 g·kg-1（P<0.01）。图2
新窗口打开|下载原图ZIP|生成PPT图2常规施肥下稻田土壤有机质变化(a,长期监测点;b,所有监测点1988、1998、2008、2017年统计)
Fig. 2Change of SOM content in paddy soil under conventional fertilization within period of 1988 to 2017(a, data comes from long term monitoring points; b, data comes from all monitoring points in 1988, 1998, 2008, and 2017)
2.2.2 不同区域稻田土壤有机质含量的时间变化 不同稻作区域长期监测点稻田耕层土壤有机质含量变化见图3。各稻区稻田耕层土壤有机质含量均随耕作时间呈现上升趋势。土壤有机质年增长速率从高到低依次为东北（0.31 g·kg-1·a-1,P<0.01）、长江下游（0.22 g·kg-1·a-1,P<0.01）、长江中游（0.19 g·kg-1·a-1,P<0.05）、华南（0.16 g·kg-1·a-1,P<0.05）和西南（0.11 g·kg-1·a-1,P<0.05）。土壤有机质含量年均增速总体表现为从北到南依次降低的趋势。
图3
新窗口打开|下载原图ZIP|生成PPT图3不同稻作区域稻田耕层土壤有机质含量变化
拟合曲线上下虚线为95%置信区间
Fig. 3Change of SOM content in paddy soil in different region within period of 1988 to 2017
The dotted lines at fitted curve up and down is the 95% confidence interval curve fitting
2.2.3 不同区域有机质含量变化的点位特征 通过对不同区域长期监测点有机质含量的定位跟踪,1988—2017年间全国140个长期监测点中,58个监测点稻田土壤有机质含量显著上升,占总量的41.4%（表2）。44个监测点稻田土壤有机质含量显著下降,占总量的31.4%,另外有27.1%的长期监测点稻田土壤有机质含量无显著上升或下降趋势。受到长期监测点地理位置、气候、种植制度、肥料投入等影响,1988—2017年间长江中游地区52个长期定位监测点中,48.1%的监测点土壤有机质含量上升,42.3%的监测点下降,9.1%的监测点无显著变化。华南地区31个长期定位监测点中32.3%监测点的有机质含量上升,25.8%下降,41.9%无显著变化。长江下游地区29个长期定位监测点中41.4%上升,24.1%下降,34.5%无显著变化。西南地区22个长期定位监测点中36.4%上升,22.7%下降,40.9%无显著变化。东北地区6个长期定位监测点中50.0%上升,33.3%下降,16.7%无显著变化。
Table 2
表2
表2不同区域长期监测点土壤有机质含量变化统计
Table 2
| 区域 Region | 长期监测点 No. of long-term monitoring points (No.) | 上升点 No. of points for SOM increasing (No.) | 下降点 No. of points for SOM decline (No.) | 无变化 No. of points for SOM no change (No.) |
|---|---|---|---|---|
| 长江中游MYR | 52 | 25 | 22 | 5 |
| 长江下游LYR | 29 | 12 | 7 | 10 |
| 华南SC | 31 | 10 | 8 | 13 |
| 西南SW | 22 | 8 | 5 | 9 |
| 东北NE | 6 | 3 | 2 | 1 |
| 全国National | 140 | 58 | 44 | 38 |
新窗口打开|下载CSV
2.3 土壤有机质含量变化影响因素
土壤有机质含量受土壤类型、气候特征、种植制度以及施肥等的影响。不同区域土壤有机质含量对气温和降水量响应关系不同（图4）。从东到西随经度变化以及从南到北随纬度变化,土壤有机质含量与年均温度相关系数呈下降趋势,两者由正相关逐渐变化为显著负相关（P<0.05）。从东到西随经度变化,土壤有机质含量与年均降水量在<E105°、E110°—115°、>125°区间表现为负相关,在E105°—110°、E115°— 120°、E120°—125°区域为正相关（P<0.05）,其相关系数整体表现为两头低,中间高。从南到北随纬度变化,土壤有机质含量与年均降水量由正相关关系逐渐变化为负相关（P<0.05）,相关系数随纬度有下降趋势。图4
新窗口打开|下载原图ZIP|生成PPT图4稻田土壤有机质含量与年均温度和降水量相关关系随经度和纬度变化
Fig. 4The relationships between the SOM content and annual average air temperature, precipitation following change with longitude and latitude
从现有监测点位水稻土类型来看（图5-a）,潜育型水稻土的稻田耕层土壤有机质平均含量为38.9 g·kg-1,显著高于其他类型水稻土（P<0.05）。耕层土壤有机质含量受种植制度影响相对较少,一年三熟制稻田耕层土壤有机质平均含量要略高于一年两熟和一年一熟制稻田（图5-b）。土壤有机质与氮肥投入响应关系表明,在投入量0—200 kg·hm-2·a-1下,土壤有机质与氮肥投入呈负相关（图5-c,P<0.05）。年投入量200—300 kg·hm-2·a-1下,土壤有机质与氮肥投入呈极显著正相关（P<0.01）。年投入量大于300 kg·hm-2·a-1下,土壤有机质与氮肥年投入量极显著负相关（P<0.01）。
图5
新窗口打开|下载原图ZIP|生成PPT图5不同水稻土类型（a）、种植制度（b）以及氮肥投入量（c）稻田的耕层土壤有机质含量变化
Fig. 5The change of SOM content with different paddy soil types (a), different cropping systems (b) and N fertilizer applications (c)
2.4 土壤有机质变化与土壤容重和耕层深度关系
土壤有机质含量与土壤容重及耕层深度存在响应关系。通常情况下有机质含量高,其土壤疏松,结构好,容重低,耕层深厚。通过对我国稻田耕层土壤602组有机质含量与容重数据做线性回归获得容重与土壤有机质含量的经验方程：y（容重g·cm-3）= -0.0049×SOM(g·kg-1) + 1.3739 （R2 = 0.1198, n = 602）（图6-a）。同样,对670组耕层深度数据与土壤有机质含量获得经验方程：y（SOM g·kg-1）=0.2879×T（耕层厚度 cm）+ 25.3651（R2 = 0.0120, n = 670）（图6-b）。图6
新窗口打开|下载原图ZIP|生成PPT图6稻田土壤有机质与土壤容重（a）及耕层深度（b）的关系
Fig. 6Correlations between bulk density and SOM content (a), SOM and plough depth (b) content for the plough layers of the paddy soil
3 讨论
3.1 土壤有机质时空变化特征
20世纪80年代以来,随着我国农业投入的增加和农业科技快速发展,水稻总产量持续上升,农作物秸秆资源数量和还田比例持续增加,我国稻田耕层土壤有机质含量整体呈现上升趋势。本研究得出近30年全国稻田耕层有机质含量平均增加约3.49 g·kg-1,年均增速0.09—0.12 g·kg-1。与前人观点基本相似[3,4]。从区域来看,受到各地水热条件、种植模式和肥料投入等影响,稻田土壤有机质含量上升速率存在差异,年均递增速率呈现从南到北依次增加趋势,结果与李建军等的观点相似[39]。我国稻田土壤也存在提升和发展不平衡状况,在全国耕地质量长期监测点位中,约2/3以上的点位稻田土壤有机质含量保持稳定或呈增加趋势,其结果略低于黄耀等文献调研结果[3]。受时间跨度、点位和数据来源等影响,以往研究大多基于文献调研或模型模拟研究国家尺度农田土壤有机质动态变化[2,3,4]。本研究依托国家级耕地质量长期定位监测点,具有长期稳定,定位精准,能真实反应农业生产方式和投入变化情况,数据可靠性高等特点。我国稻田土壤有机质提升技术措施主要包括农作物秸秆还田、施用有机肥或化肥有机肥配施以及种植绿肥[40,41,42]。稻田耕层土壤有机质含量明显高于全国耕地土壤以及旱地耕作土壤[4],其中10个省份超过30.0 g·kg-1。在不同区域,稻田土壤有机质含量呈现明显的时空变异性[2,3,4]。长江中游和华南为我国典型双季稻产区,水稻生产水平普遍较高,具有较好的水热条件,有利于秸秆腐解,其稻田土壤有机质含量整体较高。长江中游、华南和东北稻田耕层土壤有机质含量较西南和长江下游高,原因可能是与后两地为我国典型水旱轮作区域,稻田水旱交替加速土壤有机质分解有关[43,44]。
3.2 土壤有机质变化因素分析
稻田土壤有机质主要来源作物根茬、秸秆、绿肥还田,有机物料投入等。土壤有机质含量在固持和分解中维持动态平衡,影响稻田土壤有机质含量的因素有气候、土壤类型、地形、施肥和耕作措施等[2, 45-47]。温度和水分是决定土壤有机质输入和分解的气候因子,其一方面影响作物产量,制约土壤有机质输入量;另一方面对土壤水热状况和微生物活动产生深远影响[48]。本研究表明,高纬度地区,稻田土壤有机质含量与年均温度显著负相关,说明温度越高,有机质分解越快。低纬度地区,稻田土壤有机质含量与年均温度呈正相关,温度越高,越有利于作物生长,累积更多的碳投入[48,49]。从东到西,稻田土壤有机质含量与年均温度由正相关,转变为负相关,长江下游、华南地区东部年均气温对土壤有机质积累起促进作用,而到西南地区,年均气温则对土壤有机质分解起主导作用。从稻田土壤有机质与年降水量关系来看,在<E105°、E110°—115°、>E125°区间,降水加剧了有机质分解,两者表现为负相关,在E105°—110°、E115°—120°、E120°—125°区域,随着降水量增加,稻田淹水时间和淹水量增加,产生还原环境,有利于缓解土壤有机质矿化分解,增加土壤有机质积累[46]。随着纬度增加,稻田土壤有机质与年降水量之间相关系数有下降趋势。总体而言,温度和水分二者的综合配置影响稻田土壤有机质含量的地带性分布。施肥是影响土壤有机质至关重要的因素。长期施肥显著提高土壤有机质含量[50,51,52]。全国耕地质量监测数据揭示稻田土壤有机质与肥料投入存在响应关系。合适的氮肥年投入量（200—300 kgN·hm-2·a-1）能提升土壤有机质含量,较低和过高氮肥年投入量均不利于土壤有机质含量提升。目前南方的长江下游、长江中游和华南等区域稻田氮肥年投入量普遍较高。因此,减肥是必然选择,土壤有机质含量提升要与化肥减施有机结合,协调发展。就我国现有肥料投入水平来看,生产上应该以“减氮”为原则,采用秸秆还田和有机肥替代部分化肥,达到减施、提质和增效目的。水稻土类型和种植制度等主要通过土壤水热状况、微生物种群和外源投入等对稻田土壤有机质含量产生影响。
3.3 有机质与土壤容重及耕层深度的关系
土壤有机质对土壤质量及功能的调节起关键作用,较低的土壤有机质会降低土壤结构的稳定性。研究表明,土壤有机质提升有利于增加土壤孔隙,降低土壤容重,增厚土壤耕层 [53,54,55]。WU和CALLESEN等[55,56]分别利用中国矿质土壤和加拿大森林土壤拟合土壤容重与有机质含量。本研究得出稻田土壤有机质含量与土壤容重响应关系,与PAN等[8]结果基本一致。通过拟合的经验方程,可用来补充缺失土壤容重值,为计算稻田土壤碳库储量提供支撑。土壤有机质有利于构建肥沃土壤耕层。相反,合适土壤耕层深度有利于土壤微生物活动,影响土壤有机质累积和分解。本研究结果也表明,稻田土壤有机质含量与耕层深度呈正相关关系（P<0.01）,但两者相关性不如土壤容重,耕层深度可能与稻田管理措施,比如土壤翻耕深度、次数、以及机械化耕作管理等有关[56]。
4 结论
近30年全国稻田耕层土壤有机质含量平均上升3.49 g·kg-1,从南到北土壤有机质含量年均增速依次增加。不同区域稻田土壤有机质对年均气温和降水量响应关系不一样。从东部到西部以及纬度从低到高,土壤有机质含量与年均气温相关性由正相关转变为负相关。氮肥年投入量、水稻土类型以及种植制度等对稻田土壤有机质产生影响。稻田土壤有机质含量与土壤容重及耕层深度有响应关系,提升土壤有机质有利于降低土壤容重,土壤有机质含量随土壤耕层增加而呈上升趋势。参考文献 原文顺序
文献年度倒序
文中引用次数倒序
被引期刊影响因子
[本文引用: 1]
URL [本文引用: 4]
Soil organic carbon (SOC) is an important component of the global carbon cycle, and it has direct effects on the global carbon balance. Better understanding of the controlling factors of SOC and how SOC may respond to environmental changes are important to the accuracy for predicting the consequences of SOC under global change and evaluating the carbon budget. In this paper, the effects of climate, atmospheric composition, vegetation, soil property, land use and management practices on soil organic carbon (SOC) are presented. Based on this, some important tasks are also proposed, including (1) quantifying processes and states of SOC; (2) determining the controlling factors; (3) the effects of nitrogen deposition on SOC; (4) the responses and feedback of SOC to climate variability; and (5) the synthetic simulating SOC dynamics.
URL [本文引用: 4]
Soil organic carbon (SOC) is an important component of the global carbon cycle, and it has direct effects on the global carbon balance. Better understanding of the controlling factors of SOC and how SOC may respond to environmental changes are important to the accuracy for predicting the consequences of SOC under global change and evaluating the carbon budget. In this paper, the effects of climate, atmospheric composition, vegetation, soil property, land use and management practices on soil organic carbon (SOC) are presented. Based on this, some important tasks are also proposed, including (1) quantifying processes and states of SOC; (2) determining the controlling factors; (3) the effects of nitrogen deposition on SOC; (4) the responses and feedback of SOC to climate variability; and (5) the synthetic simulating SOC dynamics.
URL [本文引用: 8]
调研并分析了中国大陆1993年以来关于区域农田土壤有机碳变化的文献200余篇. 为了客观评价中国大陆农田有机碳的变化, 从中选出132篇具有代表性的文献, 这些文献涵盖了不同地区60000余个土壤样品的测定结果. 分析结果表明, 近20年来占中国大陆农田面积53%~59%的土壤有机碳含量呈增长趋势, 30%~31%呈下降趋势, 4%~6%基本持平. 进一步分析结果指出, 中国大陆农田表土有机碳贮量总体增加了311.3~401.4 Tg. 其中, 华东和华北地区增加明显, 但东北地区呈下降趋势. 有机碳含量增加明显的土壤类型为水稻土和潮土, 黑土下降显著. 有机碳含量增加主要归因于秸秆还田与有机肥施用、化肥投入增加与合理的养分配比以及少(免)耕技术的推广; 黑土区有机碳含量下降的主要原因是水土流失和投入不足. 为了有效地促进农田土壤碳固定, 最大限度地遏制东北地区土壤有机碳下降的趋势, 未来应通过配套技术的研究、农户培训和政府补贴等措施, 进一步推广秸秆还田、平衡施肥、少(免)耕等保护性耕作措施, 加大水土流失的综合治理力度. 与此同时, 为了应对后《京都议定书》时代对中国可能产生的减排压力, 未来需加强4个方面的研究: (1)第二次土壤普查期间及目前中国农田土壤有机碳贮量, (2)由自然因素和人为因素控制的农田土壤有机碳变化机理, (3)增加土壤碳固定及减少碳损失的有效途径, (4)农田土壤的固碳潜力及未来演变趋势.
URL [本文引用: 8]
调研并分析了中国大陆1993年以来关于区域农田土壤有机碳变化的文献200余篇. 为了客观评价中国大陆农田有机碳的变化, 从中选出132篇具有代表性的文献, 这些文献涵盖了不同地区60000余个土壤样品的测定结果. 分析结果表明, 近20年来占中国大陆农田面积53%~59%的土壤有机碳含量呈增长趋势, 30%~31%呈下降趋势, 4%~6%基本持平. 进一步分析结果指出, 中国大陆农田表土有机碳贮量总体增加了311.3~401.4 Tg. 其中, 华东和华北地区增加明显, 但东北地区呈下降趋势. 有机碳含量增加明显的土壤类型为水稻土和潮土, 黑土下降显著. 有机碳含量增加主要归因于秸秆还田与有机肥施用、化肥投入增加与合理的养分配比以及少(免)耕技术的推广; 黑土区有机碳含量下降的主要原因是水土流失和投入不足. 为了有效地促进农田土壤碳固定, 最大限度地遏制东北地区土壤有机碳下降的趋势, 未来应通过配套技术的研究、农户培训和政府补贴等措施, 进一步推广秸秆还田、平衡施肥、少(免)耕等保护性耕作措施, 加大水土流失的综合治理力度. 与此同时, 为了应对后《京都议定书》时代对中国可能产生的减排压力, 未来需加强4个方面的研究: (1)第二次土壤普查期间及目前中国农田土壤有机碳贮量, (2)由自然因素和人为因素控制的农田土壤有机碳变化机理, (3)增加土壤碳固定及减少碳损失的有效途径, (4)农田土壤的固碳潜力及未来演变趋势.
[本文引用: 7]
[本文引用: 7]
[本文引用: 1]
[本文引用: 1]
[本文引用: 2]
[本文引用: 2]
DOI:10.1073/pnas.1700291115URL [本文引用: 1]
DOI:10.1111/gcb.2004.10.issue-1URL [本文引用: 3]
[本文引用: 1]
[本文引用: 1]
[本文引用: 2]
[本文引用: 2]
[本文引用: 2]
[本文引用: 2]
DOI:10.3864/j.issn.0578-1752.2019.06.007URL [本文引用: 2]
【目的】 土壤有机质（SOM）是评价土壤肥力和土壤碳库的重要指标。由于复杂的成土过程及人类活动的影响,SOM通常存在较强的时空变异性。研究SOM的时空变异特征可为农业种植结构调整、应对全球气候变化提供重要参考依据。【方法】以海南岛为研究区域,通过资料收集、野外调查、采样与分析获取全国第二次土壤普查（1980s）和2012年0—20 cm土层SOM含量数据,首先采用随机森林模型分别对两个时期训练集410个、128个样点SOM空间分布规律进行预测,并通过验证集103个、32个验证点对模型精度进行验证;采用统计学方法,结合农业统计数据,研究时隔30年海南岛不同土地利用类型SOM时空变异特征,并对驱动因素进行探讨。【结果】1980s SOM含量均值为20.57 g·kg -1,呈现出从西南向东北降低的空间分布趋势,全岛SOM含量主要集中在15—20和20—30 g·kg -1两个等级,共占全岛面积的75.29%;2012年SOM含量均值为15.89 g·kg -1,呈现出西南和东北高,西部、南部沿海低的空间分布趋势,SOM含量主要集中在10—15和15—20 g·kg -1两个等级,共占全岛面积的78.28%,而15—20和20—30 g·kg -1两个等级占全岛面积66.04%,同1980s相比减少了9.25个百分点。【结论】 （1）时隔近30年,海南岛SOM含量整体呈减少趋势。2012年SOM平均含量较1980s减少了4.68 g·kg -1,减少率为22.75%。其中水田的SOM含量减少最为明显,减少了6.42 g·kg -1,减少率为27.34%;其次为园地,减少了2.65 g·kg -1,减少率为14.25%;而旱地减少量最小,为1.28 g·kg -1,减少率为8.84%;（2）水稻连作改为稻菜轮作（水田连作改为水旱轮作）、林地开垦为园地、土地利用强度加大是造成海南岛SOM含量下降的主要原因。
DOI:10.3864/j.issn.0578-1752.2019.06.007URL [本文引用: 2]
【目的】 土壤有机质（SOM）是评价土壤肥力和土壤碳库的重要指标。由于复杂的成土过程及人类活动的影响,SOM通常存在较强的时空变异性。研究SOM的时空变异特征可为农业种植结构调整、应对全球气候变化提供重要参考依据。【方法】以海南岛为研究区域,通过资料收集、野外调查、采样与分析获取全国第二次土壤普查（1980s）和2012年0—20 cm土层SOM含量数据,首先采用随机森林模型分别对两个时期训练集410个、128个样点SOM空间分布规律进行预测,并通过验证集103个、32个验证点对模型精度进行验证;采用统计学方法,结合农业统计数据,研究时隔30年海南岛不同土地利用类型SOM时空变异特征,并对驱动因素进行探讨。【结果】1980s SOM含量均值为20.57 g·kg -1,呈现出从西南向东北降低的空间分布趋势,全岛SOM含量主要集中在15—20和20—30 g·kg -1两个等级,共占全岛面积的75.29%;2012年SOM含量均值为15.89 g·kg -1,呈现出西南和东北高,西部、南部沿海低的空间分布趋势,SOM含量主要集中在10—15和15—20 g·kg -1两个等级,共占全岛面积的78.28%,而15—20和20—30 g·kg -1两个等级占全岛面积66.04%,同1980s相比减少了9.25个百分点。【结论】 （1）时隔近30年,海南岛SOM含量整体呈减少趋势。2012年SOM平均含量较1980s减少了4.68 g·kg -1,减少率为22.75%。其中水田的SOM含量减少最为明显,减少了6.42 g·kg -1,减少率为27.34%;其次为园地,减少了2.65 g·kg -1,减少率为14.25%;而旱地减少量最小,为1.28 g·kg -1,减少率为8.84%;（2）水稻连作改为稻菜轮作（水田连作改为水旱轮作）、林地开垦为园地、土地利用强度加大是造成海南岛SOM含量下降的主要原因。
URL [本文引用: 1]
【Objective】The objective of this study was to explore the spatial-temporal variability of soil organic matter (SOM) and its influencing factors, and to provide a firm scientific foundation for soil fertility assessment and management. 【Method】SOM content in arable layer in 1980, 1990 and 2000 in Daxing County of Beijing was obtained by collecting data in the Second National Soil Survey (SNSS) and recent measures. The general statistics and geostatistics methods were used to analyze the data. 【Result】The average SOM content at different times were 9.64 g·kg-1, 12.76 g·kg-1 and 12.69 g·kg-1, respectively. The semivariance analysis showed that their spatial correlation distances at different times were 80.5 km, 59.2 km and 49.0 km, respectively, showing a descending trend. Kriging method was applied to estimate the unobserved points and as a result SOM content contour maps were derived, and the map indicated a decreasing trend from north to south across the county for SOM content. The SOM content had been classified into six categories (bellow 6, 6 to10, 10 to 12, 12 to 15, 15 to 20 and above 20 g·kg-1) according to the standards set by SNSS. The SOM changed slowly from low to high category based on the accumulation of SOM in the low category from 1980 to 2000. During the last 20 years, the area with the highest and the second highest category of SOM content changed from 0 to 8.0% and 14.3% of the total area. The area with the third category for SOM content increased from 23.0% to 37.1% of the total area, respectively. The area with the forth category for SOM content decreased little, about 2.19% of the total area. The area with the fifth category for SOM content decreased sharply, about 50.4% of the total area. 【Conclusion】SOM content increasing trend might be attribute to the widespread practices of mulching and organic manure application. With the yield improvement, some regions have exhibited SOM deficit and attention should be paid to the fertilization of SOM.
URL [本文引用: 1]
【Objective】The objective of this study was to explore the spatial-temporal variability of soil organic matter (SOM) and its influencing factors, and to provide a firm scientific foundation for soil fertility assessment and management. 【Method】SOM content in arable layer in 1980, 1990 and 2000 in Daxing County of Beijing was obtained by collecting data in the Second National Soil Survey (SNSS) and recent measures. The general statistics and geostatistics methods were used to analyze the data. 【Result】The average SOM content at different times were 9.64 g·kg-1, 12.76 g·kg-1 and 12.69 g·kg-1, respectively. The semivariance analysis showed that their spatial correlation distances at different times were 80.5 km, 59.2 km and 49.0 km, respectively, showing a descending trend. Kriging method was applied to estimate the unobserved points and as a result SOM content contour maps were derived, and the map indicated a decreasing trend from north to south across the county for SOM content. The SOM content had been classified into six categories (bellow 6, 6 to10, 10 to 12, 12 to 15, 15 to 20 and above 20 g·kg-1) according to the standards set by SNSS. The SOM changed slowly from low to high category based on the accumulation of SOM in the low category from 1980 to 2000. During the last 20 years, the area with the highest and the second highest category of SOM content changed from 0 to 8.0% and 14.3% of the total area. The area with the third category for SOM content increased from 23.0% to 37.1% of the total area, respectively. The area with the forth category for SOM content decreased little, about 2.19% of the total area. The area with the fifth category for SOM content decreased sharply, about 50.4% of the total area. 【Conclusion】SOM content increasing trend might be attribute to the widespread practices of mulching and organic manure application. With the yield improvement, some regions have exhibited SOM deficit and attention should be paid to the fertilization of SOM.
URL [本文引用: 1]
By the methods of field sampling and laboratory analysis, this paper studied thevariations of soil organic carbon (SOC) and total nitrogen (TN) contents and SOC density under different land use types in Shanghai. Significant differenceswere observed in the test parameters among- different land use types. The SOCdensity was the highest in paddy field (3.86 kg·m-2), followed by in upland (3.17 kg·m-2), forestland (3.15 kg·m-2), abandoned land (2.73 kg·m-2), urban lawn ( 2.65 kg·m-2), garden land (2.13 kg·m-2 ), and tidal flat (1.38 kg·m-2). The assessment on the effects of three types of land use change on the test parameters showed that the conversion of paddy field into upland resulted in a significant decrease of SOC and TN contents and SOC density；the abandonment of farmland was not an effective way in improving SOC storage in the Yangtze Delta region with abundant water and heatresources, high soil fertility, and high level of field management; while the 4-5 years conversion of paddy field into artificial forestland decreased the SOC and TN contents and SOC density, suggesting that in a short term, the soil carbon sequestration effect of the conversion from paddy field to forestland was at a low level, due to the limitation of vegetation productivity.
URL [本文引用: 1]
By the methods of field sampling and laboratory analysis, this paper studied thevariations of soil organic carbon (SOC) and total nitrogen (TN) contents and SOC density under different land use types in Shanghai. Significant differenceswere observed in the test parameters among- different land use types. The SOCdensity was the highest in paddy field (3.86 kg·m-2), followed by in upland (3.17 kg·m-2), forestland (3.15 kg·m-2), abandoned land (2.73 kg·m-2), urban lawn ( 2.65 kg·m-2), garden land (2.13 kg·m-2 ), and tidal flat (1.38 kg·m-2). The assessment on the effects of three types of land use change on the test parameters showed that the conversion of paddy field into upland resulted in a significant decrease of SOC and TN contents and SOC density；the abandonment of farmland was not an effective way in improving SOC storage in the Yangtze Delta region with abundant water and heatresources, high soil fertility, and high level of field management; while the 4-5 years conversion of paddy field into artificial forestland decreased the SOC and TN contents and SOC density, suggesting that in a short term, the soil carbon sequestration effect of the conversion from paddy field to forestland was at a low level, due to the limitation of vegetation productivity.
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
DOI:10.11821/xb200711001URL [本文引用: 1]
Land use/cover change (LUCC) is widely recognized as one of the most important driving forces of global carbon cycles. The influence of LUCC from native forest to plantations, secondary forest, orchard and arable land on soil organic carbon (SOC) stores and quality was investigated by using "space for time" method in mid-subtropical mountainous area of southern China. The results show that LUCC has led to great decreased SOC stocks and quality. Considerable SOC and light-fraction organic carbon (LFOC) have been stored in native forest (142.2 t hm-2 and 14.8 t·hm-2, respectively). When native forest was converted to plantations, secondary forest, orchard and arable land, the SOC stocks decreased by 25.6% -28%.7%, 38.0%, 31.8% and 51.2%, respectively. The LFOC stocks decreased by 52.2-57.2% when native forest was converted to woodland plantations and second forest, and by 82.1% -84.2% when to economic plantation, orchard and arable land. After the conversion, the ratios of LFOC to SOC (0-60 cm) decreased from 13.3% to about 3.0%-10.7%. The SOC and LFOC stored in the upper 20 cm soil were more sensitive to LUCC when compared to the subsurface soil layer. Comparison suggests that the effects of the above mentioned LUCC on carbon release and quality deline were greater than the global average level, which could be explained by the vulnerable natural environment and special human management practices. Thus, it is significant to protect vulnerable environment, restore vegetation coverage and afforest plantation reasonably in mountainous area in mid-subtropics, for enhancing soil carbon sequestration, mitigating elevated atmospheric CO2 and sustainably developing ecological services.
DOI:10.11821/xb200711001URL [本文引用: 1]
Land use/cover change (LUCC) is widely recognized as one of the most important driving forces of global carbon cycles. The influence of LUCC from native forest to plantations, secondary forest, orchard and arable land on soil organic carbon (SOC) stores and quality was investigated by using "space for time" method in mid-subtropical mountainous area of southern China. The results show that LUCC has led to great decreased SOC stocks and quality. Considerable SOC and light-fraction organic carbon (LFOC) have been stored in native forest (142.2 t hm-2 and 14.8 t·hm-2, respectively). When native forest was converted to plantations, secondary forest, orchard and arable land, the SOC stocks decreased by 25.6% -28%.7%, 38.0%, 31.8% and 51.2%, respectively. The LFOC stocks decreased by 52.2-57.2% when native forest was converted to woodland plantations and second forest, and by 82.1% -84.2% when to economic plantation, orchard and arable land. After the conversion, the ratios of LFOC to SOC (0-60 cm) decreased from 13.3% to about 3.0%-10.7%. The SOC and LFOC stored in the upper 20 cm soil were more sensitive to LUCC when compared to the subsurface soil layer. Comparison suggests that the effects of the above mentioned LUCC on carbon release and quality deline were greater than the global average level, which could be explained by the vulnerable natural environment and special human management practices. Thus, it is significant to protect vulnerable environment, restore vegetation coverage and afforest plantation reasonably in mountainous area in mid-subtropics, for enhancing soil carbon sequestration, mitigating elevated atmospheric CO2 and sustainably developing ecological services.
DOI:10.11820/dlkxjz.2006.02.013URL [本文引用: 1]
Analysis and forecast on the spatial distribution and dynamics of soil properties is an important element of sustainable land management. Spatial variation of soil organic matter was analyzed according to different land use types and different topography conditions, based on data from 254 points of surface soil (0~20cm) in Hengshan county on the Loess Plateau (NW China). Correlation analyses were carried out between the soil organic matter and the terrain attributes and remote sensing indices. Finally, the land use types and the terrain attributes and remote sensing indices were used to predict soil organic matter spatial distribution by multiple-linear regression analysis. Significant differences in soil organic matter among different land use types were found, the highest values in soil organic matter were measured in soils from paddy field, and lower values in the soils from woodland and shrub land. For soil organic matter, the tendency was: paddy field>irrigated farmland>terrace farmland>check-dam farmland>grassland>slope farmland>woodland>shrub land. In different slope gradients, soil organic matter in ‘0~3°’ gradients was significantly higher than other slope gradient classes. There was little difference in soil organic matter among different slope aspects, but there was a tendency that soil organic matter in northern aspects was higher. Different correlations were found between the soil organic matter and the terrain attributes and remote sensing indices. It was found that there are positive correlations between soil organic matter and the COSα, CTI, MSAVI and WI. There is a strong negative correlation between soil organic matter and elevation. Using environmental variables to predict soil organic matter, the regression model explains 34.6% of the variability of the measured soil organic matter. But the variation is rather large and there is a more smoothing effect on the predicted values for soil organic matter.
DOI:10.11820/dlkxjz.2006.02.013URL [本文引用: 1]
Analysis and forecast on the spatial distribution and dynamics of soil properties is an important element of sustainable land management. Spatial variation of soil organic matter was analyzed according to different land use types and different topography conditions, based on data from 254 points of surface soil (0~20cm) in Hengshan county on the Loess Plateau (NW China). Correlation analyses were carried out between the soil organic matter and the terrain attributes and remote sensing indices. Finally, the land use types and the terrain attributes and remote sensing indices were used to predict soil organic matter spatial distribution by multiple-linear regression analysis. Significant differences in soil organic matter among different land use types were found, the highest values in soil organic matter were measured in soils from paddy field, and lower values in the soils from woodland and shrub land. For soil organic matter, the tendency was: paddy field>irrigated farmland>terrace farmland>check-dam farmland>grassland>slope farmland>woodland>shrub land. In different slope gradients, soil organic matter in ‘0~3°’ gradients was significantly higher than other slope gradient classes. There was little difference in soil organic matter among different slope aspects, but there was a tendency that soil organic matter in northern aspects was higher. Different correlations were found between the soil organic matter and the terrain attributes and remote sensing indices. It was found that there are positive correlations between soil organic matter and the COSα, CTI, MSAVI and WI. There is a strong negative correlation between soil organic matter and elevation. Using environmental variables to predict soil organic matter, the regression model explains 34.6% of the variability of the measured soil organic matter. But the variation is rather large and there is a more smoothing effect on the predicted values for soil organic matter.
DOI:10.1016/j.agee.2017.05.003URL [本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 2]
[本文引用: 2]
DOI:10.11674/zwyf.2015.0602URL [本文引用: 1]
目的 施肥是农业增产的主要措施,显著影响着土壤质量的变化,因此,长期施肥与土壤质量关系一直是植物营养与肥料研究的热点。近30年来,我国农业生产投入不断增长,粮食产量自上世纪90年代起实现了“十一连增”,对土壤的养分收支影响巨大。研究我国近30年主要农田土壤质量的变化,对维持和提高土壤质量,保持粮食高产稳产有重要意义。方法 我国持续进行的长期肥料试验约50个,覆盖了主要种植制度和土壤类型。依据本专辑论文有关长期施肥对土壤主要理化性状的影响,综述了我国长期不同施肥模式和施肥量土壤质量的变化特征,并依据研究内容和国际研究热点提出了我国今后长期定位试验研究的方向及驱动力。结果 1) 本专辑收集了论文31篇,60%以上研究内容集中在土壤有机质和磷素有效性的演变,表明土壤有机质质量和磷素库源平衡在我国农田土壤质量评估中起着决定性的作用。2)连续30年单施化肥,东北黑土有机质呈缓慢下降趋势,每10年下降1 g/kg左右,其他区域稳定缓慢上升,每10年上升1.4~2.5 g/kg。长期无机肥配施有机肥及秸秆还田,土壤有机质呈显著上升趋势,30年平均上升幅度西北和华北高达51%和68%,南方旱地和长江流域水田平均为24%。3)我国农田有机物料碳的利用效率平均为16.3%,呈现随水热梯度增加而降低的趋势。其中,西北和东北地区平均为22%~26%,明显高于华北的13%和南方旱地或水田的10%; 4)土壤有效磷含量受施肥影响显著。每季作物施磷(P)20~33 kg/hm2,土壤全磷和有效磷可维持平衡或明显增加,年平均上升速率因土壤类型和磷肥施用量不同存在较大差异,每年最大可提高2.1 mg/kg; 化肥配施有机肥有助于活化土壤磷,对于有效磷有更大的提升空间,最高可达9.3 mg/kg。5)施用化肥,土壤磷素以有效性较高的无机形态(Ca2-P、 Ca8-P、 Al-P、 Fe-P)累积,化肥配施有机肥显著增加了活性较高的有机磷组分(活性有机磷、 中活性有机磷),有利于土壤有效磷的稳定供给。展望我国目前集约化种植下,农田有机物料的投入仍是影响土壤有机质平衡的第一要素。我国土壤有机质和有效磷含量仍有增加的空间,还需加强有机物料的投入。土壤质量研究今后还应加强土壤生物指标和土壤生态和健康功能研究,加强土壤质量演变趋势研究,采用模型模拟、 预测与预警土壤质量,并通过模型的选择和参数的确定促进模型在生产实践中的应用。
DOI:10.11674/zwyf.2015.0602URL [本文引用: 1]
目的 施肥是农业增产的主要措施,显著影响着土壤质量的变化,因此,长期施肥与土壤质量关系一直是植物营养与肥料研究的热点。近30年来,我国农业生产投入不断增长,粮食产量自上世纪90年代起实现了“十一连增”,对土壤的养分收支影响巨大。研究我国近30年主要农田土壤质量的变化,对维持和提高土壤质量,保持粮食高产稳产有重要意义。方法 我国持续进行的长期肥料试验约50个,覆盖了主要种植制度和土壤类型。依据本专辑论文有关长期施肥对土壤主要理化性状的影响,综述了我国长期不同施肥模式和施肥量土壤质量的变化特征,并依据研究内容和国际研究热点提出了我国今后长期定位试验研究的方向及驱动力。结果 1) 本专辑收集了论文31篇,60%以上研究内容集中在土壤有机质和磷素有效性的演变,表明土壤有机质质量和磷素库源平衡在我国农田土壤质量评估中起着决定性的作用。2)连续30年单施化肥,东北黑土有机质呈缓慢下降趋势,每10年下降1 g/kg左右,其他区域稳定缓慢上升,每10年上升1.4~2.5 g/kg。长期无机肥配施有机肥及秸秆还田,土壤有机质呈显著上升趋势,30年平均上升幅度西北和华北高达51%和68%,南方旱地和长江流域水田平均为24%。3)我国农田有机物料碳的利用效率平均为16.3%,呈现随水热梯度增加而降低的趋势。其中,西北和东北地区平均为22%~26%,明显高于华北的13%和南方旱地或水田的10%; 4)土壤有效磷含量受施肥影响显著。每季作物施磷(P)20~33 kg/hm2,土壤全磷和有效磷可维持平衡或明显增加,年平均上升速率因土壤类型和磷肥施用量不同存在较大差异,每年最大可提高2.1 mg/kg; 化肥配施有机肥有助于活化土壤磷,对于有效磷有更大的提升空间,最高可达9.3 mg/kg。5)施用化肥,土壤磷素以有效性较高的无机形态(Ca2-P、 Ca8-P、 Al-P、 Fe-P)累积,化肥配施有机肥显著增加了活性较高的有机磷组分(活性有机磷、 中活性有机磷),有利于土壤有效磷的稳定供给。展望我国目前集约化种植下,农田有机物料的投入仍是影响土壤有机质平衡的第一要素。我国土壤有机质和有效磷含量仍有增加的空间,还需加强有机物料的投入。土壤质量研究今后还应加强土壤生物指标和土壤生态和健康功能研究,加强土壤质量演变趋势研究,采用模型模拟、 预测与预警土壤质量,并通过模型的选择和参数的确定促进模型在生产实践中的应用。
DOI:10.1007/s11368-011-0467-8URL [本文引用: 1]
Although organic amendments have been recommended as one of the practices for crop production and soil carbon sequestration, little has been done to evaluate soil organic carbon (SOC) dynamics following long-term application of organic amendments. The objective of this research were to (1) assess the effect of long-term organic amendments on SOC dynamics in rice-based systems; (2) evaluate the relationship between soil carbon sequestration and carbon input based on various mineral and organic fertilization treatments.
A multi-sites analysis was conducted on four long-term experiments with double-rice (three sites) and rice-wheat (one site) cropping systems which started in the 1980s in Southern China. We selected three groups of treatments in common at each site: (1) control (no fertilizer), (2) mineral nitrogen-phosphorus with and without potassium (NPK/NP), and (3) the combined treatments of mineral NP/NPK with pig manure (M), green manure (G, Astragalus sinicus L.), rice straw (S), and/or their combinations. Harvestable crop biomass was annually recorded for all plots. SOC in topsoil was determined in 1-5 yearly intervals after rice harvest.
Analysis showed that organic amendments sustained or significantly increased carbon biomass, but had little effects on the coefficient of variance (CV) of the carbon biomass production compared with the mineral NPK/NP treatments. With additional carbon input, organic amendments increased SOC significantly by 7-45% after 25-28 years of fertilization compared with the mineral treatments. These combined treatments sequestered carbon at a rate from 0.20 to 0.48 t ha(-1) year(-1) under the double-rice and 0.70 to 0.88 t ha(-1) year(-1) under rice-wheat cropping system. The estimated annual SOC decomposition rate ranged from 0.15 to 0.82 t ha(-1) at these studied sites. Our analyses revealed strong positive correlations between soil carbon sequestration and carbon input for all sites.
We concluded that organic amendments applied as substitution and extra nutrients had significant effect on soil carbon sequestration and served as a carbon sink for the duration of the experiments. Paddy soil high in clay content had the potential to sequester more carbon. Soil carbon sequestration efficiency-declined with carbon input at some sites with loam soil texture, suggesting applying a large amount of organic amendments is not recommended as a sustainable agricultural management practice because of the high risk of non-point environment pollution.
DOI:10.1016/j.scitotenv.2019.03.151URLPMID:30897441 [本文引用: 1]
As an important indicator of soil quality, soil organic matter (SOM) significantly contributes to land productivity and ecosystem health. Accurately mapping SOM at regional scales is of critical importance for sustainable agriculture and soil utilization management and remains a grand challenge. Many studies used soil sampling data and machine learning algorithms to predict SOM at regional scales for a given year, while few studies mapped SOM for multiple years and examined its temporal dynamics. We compared the performance of four machine learning algorithms: decision tree (DT), bagging decision tree (BDT), random forest (RF), and gradient boosting regression trees (GBRT) in mapping SOM in Hubei province, China over the 18-year period from 2000 to 2017. Our results showed that RF and DT had the highest coefficient of determination (R(2)) (0.61) and the lowest potential bias (9.48g/kg), respectively, while GBRT had the lowest mean error (ME) (1.26g/kg), root mean squared error (RMSE) (5.41g/kg) and Lin's concordance correlation coefficient (LCCC) (0.72). The SOM map based on GBRT better captured the distribution of the soil sample data than that based on RF. The trained GBRT model and the spatially explicitly data on explanatory variables (e.g., climate, terrain, remote sensing) were used to predict SOM for each 500mx500m grid cell in Hubei for the period from 2000 to 2017. Our results showed that the SOM content of cropland was relatively high in the southeast and relatively low in the north. The SOM content in the topsoil varied from 0.89 to 58.86g/kg and was averaged at 20.52g/kg. The mean cropland SOM content of the province exhibited an increasing trend from 2000 to 2017 with an increase of 0.26g/kg and a growth rate of 1.28%. Spatially, the SOM content increased in southern Hubei and decreased in central and northern parts of the province. A large portion of the areas with decreasing SOM content in northern Hubei was reclaimed cropland, while a large part of the high-quality cropland with rising SOM content in the east (~0.45x10(4)ha) was lost due to land use change (e.g., urbanization).
DOI:10.1016/j.fcr.2018.07.001URL [本文引用: 1]
[本文引用: 1]
[本文引用: 1]
DOI:10.1016/j.agee.2008.10.008URL [本文引用: 1]
DOI:10.1016/j.geoderma.2019.03.004URL [本文引用: 1]
DOI:10.1016/j.scitotenv.2017.12.199URLPMID:29275253 [本文引用: 1]
Quantifying soil organic carbon (SOC) dynamics is important in understanding changes in soil properties and carbon (C) fluxes. However, SOC measures all C fractions and it is not adequate to distinguish between the active C (AC) and recalcitrant or passive C (PC) fractions. It has been suggested that PC pools are the main drivers of long term soil C sink management. Therefore, the present study was undertaken with the objective of determining whether or not SOC fractions vary with land use changes under a humid tropical climate in the North East India. A chronosequence study was established consisting of natural forest, Imperata cylindrica grassland and 6, 15, 27 and 34yr old rubber (Hevea brasiliensis) plantations to determine changes in the different fractions of SOC and total SOC stock. SOC stocks significantly varied with soil depth in each land use practice. SOC stocks increased from 106Mgha(-1) under 6yr to 130Mgha(-1) under 34yr old rubber plantations. The SOC stocks under 34yr old plantations were 20% higher than that under I. cylindrica grassland, but 34% lower than SOC stocks recorded under natural forest soil. The proportion of AC pools decreased with increase in plantation age, AC pools being 59% of SOC stock in 6yr old stands and 33% of SOC stocks in 34yr old plantations. In contrast, the proportion of PC pools increased from 41% of SOC stock in 6yr old plantation to 67% of SOC in 34yr old plantation. In the 50-100cm soil depth, the PC pool under 27-34yr old plantations was comparable with that under natural forest but much higher than in I. cylindrica grassland. Therefore, it is concluded that old rubber plantations can play a significant role in long term soil C sink management.
DOI:10.1016/j.geoderma.2018.07.026URL [本文引用: 1]
[本文引用: 1]
[本文引用: 1]
DOI:10.3864/j.issn.0578-1752.2016.08.008URL [本文引用: 1]
【Objective】The objective of this paper is to study the differences of basic soil productivity and spatial and temporal characteristics of national paddy soil in the main grain production regions of China from the Ministry of Agriculture since 1988, provide a scientific basis of fertilization for the improvement of soil fertility and rice high yield. 【Method】Combined with the actual situation of soil, and the reference model of productivity, soil quality and other correction coefficient model derived soil productivity index model (PI) and was calculated based soil fertility index model (BPI) and verification. At the same time, the national paddy soil monitoring data was used as basis, each fertility index and weight statistics resulting weighting factor were normalized by numerical normalization. PI and BPI indexes were used for comprehensive analysis, and further verified with the yield and contribution proportion of basic soil productivity phase, thereby the differences and spatial and temporal characteristics of the basic soil productivity were quantitatively analyzed. 【Result】From 1988 to 2012, both the BPI values (P<0.05) and PI values (P<0.01) showed significant increasing trends in the districts of Yangtze River, Northeast China, Southwest China, and South China. There were significant positive correlations (P<0.05) between BPI values and fertilization yields. The BPI values in the Yangtze River region increased from 0.031 to 0.108 with the largest increasing percentage of 248.4%, followed by the BPI value in the Southern China increased from 0.127 to 0.289 with an increase of 128.0%, and that in the Northeast China and Southwest China with increase of 71.7% and 65.8%, respectively, during the past 25 years. Rice yield with fertilization of each area with the enhancement of basic soil productivity of paddy showed an increasing trend. The basic soil productivity levels (BSPI value) in Yangtze River region were significantly higher than that in the other three areas. The BSPI value in the Southwest China was the lowest, while there was no significant difference between the Northeast China and the Southern China. As for regions, the trends of BSPI values coincided with the yields under the basic fertility of soil. 【Conclusion】During the past 25 years, the basic soil productivity showed an overall upward trend in the main rice production regions of China. Soil productivity could be improved with the enhancing of basic soil productivity. In addition, on the level of current farming management (from 2003 to 2012), the order of basic soil productivity among the regions were Yangtze River region>Northeast China≥Southern China>Southwest China. In the national scale, the higher the BSPI, the higher the rice yield without fertilization, the higher the contribution proportion of basic soil productivity. On the contrary, the lower the basic soil productivity, rice output is also lower, contribution proportion of basic soil productivity is also lower.
DOI:10.3864/j.issn.0578-1752.2016.08.008URL [本文引用: 1]
【Objective】The objective of this paper is to study the differences of basic soil productivity and spatial and temporal characteristics of national paddy soil in the main grain production regions of China from the Ministry of Agriculture since 1988, provide a scientific basis of fertilization for the improvement of soil fertility and rice high yield. 【Method】Combined with the actual situation of soil, and the reference model of productivity, soil quality and other correction coefficient model derived soil productivity index model (PI) and was calculated based soil fertility index model (BPI) and verification. At the same time, the national paddy soil monitoring data was used as basis, each fertility index and weight statistics resulting weighting factor were normalized by numerical normalization. PI and BPI indexes were used for comprehensive analysis, and further verified with the yield and contribution proportion of basic soil productivity phase, thereby the differences and spatial and temporal characteristics of the basic soil productivity were quantitatively analyzed. 【Result】From 1988 to 2012, both the BPI values (P<0.05) and PI values (P<0.01) showed significant increasing trends in the districts of Yangtze River, Northeast China, Southwest China, and South China. There were significant positive correlations (P<0.05) between BPI values and fertilization yields. The BPI values in the Yangtze River region increased from 0.031 to 0.108 with the largest increasing percentage of 248.4%, followed by the BPI value in the Southern China increased from 0.127 to 0.289 with an increase of 128.0%, and that in the Northeast China and Southwest China with increase of 71.7% and 65.8%, respectively, during the past 25 years. Rice yield with fertilization of each area with the enhancement of basic soil productivity of paddy showed an increasing trend. The basic soil productivity levels (BSPI value) in Yangtze River region were significantly higher than that in the other three areas. The BSPI value in the Southwest China was the lowest, while there was no significant difference between the Northeast China and the Southern China. As for regions, the trends of BSPI values coincided with the yields under the basic fertility of soil. 【Conclusion】During the past 25 years, the basic soil productivity showed an overall upward trend in the main rice production regions of China. Soil productivity could be improved with the enhancing of basic soil productivity. In addition, on the level of current farming management (from 2003 to 2012), the order of basic soil productivity among the regions were Yangtze River region>Northeast China≥Southern China>Southwest China. In the national scale, the higher the BSPI, the higher the rice yield without fertilization, the higher the contribution proportion of basic soil productivity. On the contrary, the lower the basic soil productivity, rice output is also lower, contribution proportion of basic soil productivity is also lower.
DOI:10.11674/zwyf.2015.0110URL [本文引用: 1]
【目的】目前我国的水稻产量约占粮食总产量的一半以上,面积占耕地总面积的30%,为了探明我国水稻土土壤养分和肥力的演变特征,科学合理地指导稻田土壤养分管理和施肥,本文对长江中下游水稻主产区20世纪80年代以来国家水稻土长期动态监测数据进行了整理分析。【方法】 利用时间趋势分析和中值分析的方法对长江中下游地区稻田土壤养分随时间的变化趋势进行了分析,分别总结了土壤有机质(SOM)、全氮(TN)、碱解氮(AN)、有效磷(AP)和速效钾(AK)的含量以及土壤pH在不同监测时期的演变特征和总体变化趋势;用统计分析得出不同监测时期施肥量的变化情况;运用主成分分析的方法对上述6大肥力指标对该区土壤综合肥力属性的年代变化趋势所产生的作用和影响进行了分析,得出不同监测时期土壤肥力主要贡献因子和限制性因子的变异情况。【结果】 1)我国长江中下游地区稻田土壤有机质、全氮和碱解氮含量与监测初期相比均略有升高,其中有机质含量从监测中期到监测后期上升趋势明显 (P<0.05),碱解氮从监测初期到中期也呈显著性增加趋势 ( P<0.05); 2)监测25年来,土壤有效磷含量从12.4 mg/kg增加到12.9 mg/kg,土壤速效钾含量总体上呈稳中有升的变化趋势,与监测初期相比,监测中期和监测后期的速效钾含量分别增加了13.9 mg/kg和17.9 mg/kg; 3)土壤pH值总体呈缓慢降低的趋势,下降了0.37个单位,表明在当前的施肥和田间管理措施下我国水稻土存在一定的酸化趋势; 4)土壤全氮、碱解氮与有机质含量变化存在显著的正相关关系(P<0.01),且变化趋势基本一致; 5)与监测初期相比, 20~25年后水稻土土壤肥力主要贡献因子由全氮、碱解氮和有机质转变为全氮、碱解氮和速效钾,主要限制因素从有效磷和速效钾含量的缺乏转向pH值的逐渐降低。【结论】在农民习惯的耕作施肥管理条件下,该地区稻田土壤养分含量基本呈上升趋势,说明土壤肥力总体上得到了改善;但土壤pH在一定程度上已显现出对土壤肥力的限制性作用,所导致的酸化趋势需要关注。另外,从农田养分平衡管理的角度看,土壤速效钾和有效磷仍然是该区稻田持续生产和农业持续发展的重要影响因素,在施肥过程中对钾与磷的投入仍需加强,而氮肥施用量需要合理控制。
DOI:10.11674/zwyf.2015.0110URL [本文引用: 1]
【目的】目前我国的水稻产量约占粮食总产量的一半以上,面积占耕地总面积的30%,为了探明我国水稻土土壤养分和肥力的演变特征,科学合理地指导稻田土壤养分管理和施肥,本文对长江中下游水稻主产区20世纪80年代以来国家水稻土长期动态监测数据进行了整理分析。【方法】 利用时间趋势分析和中值分析的方法对长江中下游地区稻田土壤养分随时间的变化趋势进行了分析,分别总结了土壤有机质(SOM)、全氮(TN)、碱解氮(AN)、有效磷(AP)和速效钾(AK)的含量以及土壤pH在不同监测时期的演变特征和总体变化趋势;用统计分析得出不同监测时期施肥量的变化情况;运用主成分分析的方法对上述6大肥力指标对该区土壤综合肥力属性的年代变化趋势所产生的作用和影响进行了分析,得出不同监测时期土壤肥力主要贡献因子和限制性因子的变异情况。【结果】 1)我国长江中下游地区稻田土壤有机质、全氮和碱解氮含量与监测初期相比均略有升高,其中有机质含量从监测中期到监测后期上升趋势明显 (P<0.05),碱解氮从监测初期到中期也呈显著性增加趋势 ( P<0.05); 2)监测25年来,土壤有效磷含量从12.4 mg/kg增加到12.9 mg/kg,土壤速效钾含量总体上呈稳中有升的变化趋势,与监测初期相比,监测中期和监测后期的速效钾含量分别增加了13.9 mg/kg和17.9 mg/kg; 3)土壤pH值总体呈缓慢降低的趋势,下降了0.37个单位,表明在当前的施肥和田间管理措施下我国水稻土存在一定的酸化趋势; 4)土壤全氮、碱解氮与有机质含量变化存在显著的正相关关系(P<0.01),且变化趋势基本一致; 5)与监测初期相比, 20~25年后水稻土土壤肥力主要贡献因子由全氮、碱解氮和有机质转变为全氮、碱解氮和速效钾,主要限制因素从有效磷和速效钾含量的缺乏转向pH值的逐渐降低。【结论】在农民习惯的耕作施肥管理条件下,该地区稻田土壤养分含量基本呈上升趋势,说明土壤肥力总体上得到了改善;但土壤pH在一定程度上已显现出对土壤肥力的限制性作用,所导致的酸化趋势需要关注。另外,从农田养分平衡管理的角度看,土壤速效钾和有效磷仍然是该区稻田持续生产和农业持续发展的重要影响因素,在施肥过程中对钾与磷的投入仍需加强,而氮肥施用量需要合理控制。
DOI:10.3864/j.issn.0578-1752.2019.11.007URL [本文引用: 2]
【Objective】 A meta study was conducted to investigate the comprehensive effect of fertilization on rice yield in Chinese paddy soils during the past 30 years, and to provide a theoretical basis for the scientific correct application of fertilizers in rice cultivation areas. 【Method】 Based on the long-term paddy soil monitoring sites from Ministry of Agriculture and Rural Affairs, we conducted meta-analysis to investigate the rice yield response to no fertilization versus fertilization in different agro-climatic regions. 【Result】 Rice yield in the past 10 years (2008-2017) was significantly higher than the corresponding rice yield in 1988-1997 and 1998-2007, regardless of fertilization. The increase of rice yield with fertilization in southwest of China was by 98.5%, which was significantly higher than that of in north of China (70.3%). Fertilization increased rice yield by 99.1%, 84.2% and 78.1% during 1988-1997, 1998-2007 and 2008-2017, respectively. For the cropping system, the increase of rice yield under triple cropping system (92.0%) was significantly higher than that under single cropping system (76.2%) and double cropping system (81.9%). Fertilization increased rice yield by 85.9% under double rice cropping system, by 75.9% under single cropping system, and by 79.5% under other cropping system. Compared with no fertilizer, chemical plus organic fertilizer application increased rice yield by 88.3%, which was higher than that of single chemical fertilizer application (76.6%). Fertilization significantly increased rice yield in clay soil by 92.0%, compared with no fertilization, which significantly higher than that in sandy soil (58.0%) and loam soil (77.5%). With the increase of soil organic matter and available phosphorus, the increasing trend of fertilization on rice yield was decreased compared with no fertilization. Under higher soil pH (>7.5) and lower soil total nitrogen (<1.5 g·kg -1) and slow available potassium (<150 mg·kg -1), the rice yield increasing was more than that of corresponding the rest of level. Random forest analysis showed that the region, soil total nitrogen and cropping system had greater impact on the response ratio (RR) of rice yield. In addition, the agronomic efficiency of fertilizer was positively correlated with rice yield RR. 【Conclusion】 Although the trend of increasing rice yield by fertilization was decreasing at present, but combined appropriate chemical plus organic fertilizer, especially in southwest of China, were important measures to improve and maintain high rice yield. Base on the cropping system, combining soil texture, soil nitrogen and potassium content should be the main basis for fertilizer input in different rice cultivation areas.
DOI:10.3864/j.issn.0578-1752.2019.11.007URL [本文引用: 2]
【Objective】 A meta study was conducted to investigate the comprehensive effect of fertilization on rice yield in Chinese paddy soils during the past 30 years, and to provide a theoretical basis for the scientific correct application of fertilizers in rice cultivation areas. 【Method】 Based on the long-term paddy soil monitoring sites from Ministry of Agriculture and Rural Affairs, we conducted meta-analysis to investigate the rice yield response to no fertilization versus fertilization in different agro-climatic regions. 【Result】 Rice yield in the past 10 years (2008-2017) was significantly higher than the corresponding rice yield in 1988-1997 and 1998-2007, regardless of fertilization. The increase of rice yield with fertilization in southwest of China was by 98.5%, which was significantly higher than that of in north of China (70.3%). Fertilization increased rice yield by 99.1%, 84.2% and 78.1% during 1988-1997, 1998-2007 and 2008-2017, respectively. For the cropping system, the increase of rice yield under triple cropping system (92.0%) was significantly higher than that under single cropping system (76.2%) and double cropping system (81.9%). Fertilization increased rice yield by 85.9% under double rice cropping system, by 75.9% under single cropping system, and by 79.5% under other cropping system. Compared with no fertilizer, chemical plus organic fertilizer application increased rice yield by 88.3%, which was higher than that of single chemical fertilizer application (76.6%). Fertilization significantly increased rice yield in clay soil by 92.0%, compared with no fertilization, which significantly higher than that in sandy soil (58.0%) and loam soil (77.5%). With the increase of soil organic matter and available phosphorus, the increasing trend of fertilization on rice yield was decreased compared with no fertilization. Under higher soil pH (>7.5) and lower soil total nitrogen (<1.5 g·kg -1) and slow available potassium (<150 mg·kg -1), the rice yield increasing was more than that of corresponding the rest of level. Random forest analysis showed that the region, soil total nitrogen and cropping system had greater impact on the response ratio (RR) of rice yield. In addition, the agronomic efficiency of fertilizer was positively correlated with rice yield RR. 【Conclusion】 Although the trend of increasing rice yield by fertilization was decreasing at present, but combined appropriate chemical plus organic fertilizer, especially in southwest of China, were important measures to improve and maintain high rice yield. Base on the cropping system, combining soil texture, soil nitrogen and potassium content should be the main basis for fertilizer input in different rice cultivation areas.
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[D].
[本文引用: 1]
[D].
[本文引用: 1]
[本文引用: 1]
URL [本文引用: 1]
Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 °C for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon (DOC), hot-water extractable organic carbon (HEOC), and microbial biomass carbon (MBC) were recorded, along with cellulase and β-glucosidase activities and community- level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOC, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.
DOI:10.1016/j.scitotenv.2019.01.051URLPMID:30743900 [本文引用: 1]
Manure application is widely recognized as a method of improving soil structure and soil fertility due to additional organic matter and nutrient inputs. However, the salinity of animal manure may have a detrimental effect on soil aggregation. The objective of this study was to determine the effects of long-term animal manure application on soil aggregation, binding agents (soil organic carbon, SOC and glomalin-related soil protein, GRSP), and dispersing agents (e.g., Na(+)) and their relationships based on nine long-term fertilization experiments (12 to 39yr) across China. The two red soil experiments (Qiyang, QY and Jinxian, JX) and one paddy soil experiment in Jinxian (JX-P) were conducted in southern China (precipitation above 1200mmyr(-1)), whereas the other six experiments were established in semi-humid or arid regions in China with precipitation in the range of 500-900mmyr(-1). Each experiment included three treatments as follows: no fertilization (Control), inorganic fertilizer (NP or NPK), and a combination of inorganic fertilizer and animal manure (NPM or NPKM). Long-term animal manure application not only significantly increased the biological binding agents (i.e., SOC and GRSP) in the nine experiments but also considerably increased the dispersing agents (i.e., exchangeable Na(+)) (P<0.05), except for the paddy soil experiment. Consequently, soil aggregate stability increased after animal manure application in three experimental sites in southern China but not in the experimental sites in northern China. Aggregate stability had a positive relationship with SOC and GRSP in the experimental sites in southern China (P<0.01) but a negative relationship with exchangeable Na(+) in the experimental sites in northern China (P<0.05). The Na(+) accumulation in soils was negatively related to mean annual precipitation (P<0.001). Our study demonstrates that the long-term application of animal manure may degrade soil structure via the Na(+) accumulation.
[D].
[本文引用: 1]
[D].
[本文引用: 1]
URL [本文引用: 1]
【Objective】 This paper was to explore the effects of cropping system in paddy field of red soil on the crops growth and soil nutrient change, and to provide with effective mode for cropping system reform under bad irrigation condition. 【Method】Through located field experiments, effects of different cropping systems of paddy soil including Pasture, Paddy-Upland Rotation, Upland Cropping et al on crop growth, yield and economic benefit was studied, and the change of soil organic matter and nutrient content was investigated.【Results】The results showed that crop yield and economic benefit were all increased as well as the ratio of output/ input according to the calculation with different crops’ price in present market. The yield under Paddy-Upland Rotation was increased by 51.3%, 31.7%, 16.3% respectively, comparing to that of control (Rice-Rice-Astragali), Pasture, Upland Cropping treatments. The greatest economic benefit occurred under Paddy-Upland Rotation, whose yield was increased by 34.7%、21.4% and 2.2% comparing to that of that of control (Rice-Rice- Astragali), Pasture, Upland Cropping treatments. Comparing to that of control, the economic benefit under Pasture, Upland Cropping treatments was increased by 11.0% and 31.8% respectively. The ratio of output/input under Pasture, Paddy-Upland Rotation, Upland Cropping treatments was enhanced 0.9, 0.6 and 0.3, repectively, when compared with that of control. It is good to plant pasture for improving soil fertility since soil organic matter, total nitrogen, total phosphorus and available phosphorus were all increased. However, the content of available nitrogen, total potassium, available potassium was reduced in certain degree for all the treatments, which indicated that it is necessary to increase nitrogen, especially potassium input under this field experiment fertilization level. 【Conclusion】Under the status of present paddy fertility of red soil regions, climate and crops cultivation and management, it is feasible to alter the cropping system of paddy fields with bad irrigation condition. In order to increase crops yield, to obtain considerable economic benefit, and to better regulate agricultural structure, it is suggested that to adopt such cropping system as Pasture and Paddy-Upland Rotation.
URL [本文引用: 1]
【Objective】 This paper was to explore the effects of cropping system in paddy field of red soil on the crops growth and soil nutrient change, and to provide with effective mode for cropping system reform under bad irrigation condition. 【Method】Through located field experiments, effects of different cropping systems of paddy soil including Pasture, Paddy-Upland Rotation, Upland Cropping et al on crop growth, yield and economic benefit was studied, and the change of soil organic matter and nutrient content was investigated.【Results】The results showed that crop yield and economic benefit were all increased as well as the ratio of output/ input according to the calculation with different crops’ price in present market. The yield under Paddy-Upland Rotation was increased by 51.3%, 31.7%, 16.3% respectively, comparing to that of control (Rice-Rice-Astragali), Pasture, Upland Cropping treatments. The greatest economic benefit occurred under Paddy-Upland Rotation, whose yield was increased by 34.7%、21.4% and 2.2% comparing to that of that of control (Rice-Rice- Astragali), Pasture, Upland Cropping treatments. Comparing to that of control, the economic benefit under Pasture, Upland Cropping treatments was increased by 11.0% and 31.8% respectively. The ratio of output/input under Pasture, Paddy-Upland Rotation, Upland Cropping treatments was enhanced 0.9, 0.6 and 0.3, repectively, when compared with that of control. It is good to plant pasture for improving soil fertility since soil organic matter, total nitrogen, total phosphorus and available phosphorus were all increased. However, the content of available nitrogen, total potassium, available potassium was reduced in certain degree for all the treatments, which indicated that it is necessary to increase nitrogen, especially potassium input under this field experiment fertilization level. 【Conclusion】Under the status of present paddy fertility of red soil regions, climate and crops cultivation and management, it is feasible to alter the cropping system of paddy fields with bad irrigation condition. In order to increase crops yield, to obtain considerable economic benefit, and to better regulate agricultural structure, it is suggested that to adopt such cropping system as Pasture and Paddy-Upland Rotation.
URL [本文引用: 1]
大气温室效应气体N2O、CO2增多与全球气温变暖有着密切的关系,由于农业活动导致的碳排放量占碳总排放量的25%,因此研究农田土壤有机碳的影响因素,对增加农田碳素固定和保持,减少由于不合理的土地使用而导致大量CO2的排放,维持农业和生物圈生态系统的可持续发展有着重要意义.本文分析了温度、水分、土地开垦、休闲和撩荒、耕翻、轮作、秸秆还田、肥料管理等对土壤有机碳的影响.减少翻耕次数,增加秸秆还田,优化氮、磷、钾等养分用量及配比,是提高农田,尤其是旱地农田土壤有机碳含量,培肥、改良土壤的重要途径.
URL [本文引用: 1]
大气温室效应气体N2O、CO2增多与全球气温变暖有着密切的关系,由于农业活动导致的碳排放量占碳总排放量的25%,因此研究农田土壤有机碳的影响因素,对增加农田碳素固定和保持,减少由于不合理的土地使用而导致大量CO2的排放,维持农业和生物圈生态系统的可持续发展有着重要意义.本文分析了温度、水分、土地开垦、休闲和撩荒、耕翻、轮作、秸秆还田、肥料管理等对土壤有机碳的影响.减少翻耕次数,增加秸秆还田,优化氮、磷、钾等养分用量及配比,是提高农田,尤其是旱地农田土壤有机碳含量,培肥、改良土壤的重要途径.
[D].
[本文引用: 1]
[D].
[本文引用: 1]
DOI:10.1016/j.geoderma.2011.08.002URL [本文引用: 1]
China's rice paddies, accounting for 19% of the world's total, play an important role in soil carbon (C) sequestration. In order to reduce uncertainties from upscaling spatial processes of the DeNitrification-DeComposition (DNDC) model for improving the understanding of C sequestration under recommended management practices (RMPs), we parameterized the DNDC model with a 1:1,000,000 polygonal soil database to estimate how RMPs influence potential C sequestration of the top 30 cm of Chinese paddy soils and to identify which management practices have the greatest potential to increase soil organic carbon (SOC) in these soils. These practices include reduced/no tillage, increasing crop residue return, and increasing manure applications. A baseline and eleven RMP scenarios were projected from 2009 to 2080, including traditional and conservation tillage, increasing crop residue return, increasing manure incorporation, and the combination of these practices. The results indicated that C sequestration potential under modeled RMPs increased compared to the baseline scenario, and varied greatly from 29.2 to 847.7 Tg C towards the end of the study period with an average rate of 0.7 to 20.2 Tg C yr(-1). In general, increasing crop residue return was associated with higher rates of C sequestration when compared to increasing manure application or practicing conservation tillage. The simulations demonstrated that the most effective soil C sequestration strategy probably involves the implementation of a combination of RMPs, and that they vary by location. (C) 2011 Elsevier B.V.
URL [本文引用: 2]
Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmosphericCO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate changeon this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarizedthe research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.
URL [本文引用: 2]
Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmosphericCO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate changeon this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarizedthe research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.
URL [本文引用: 1]
To understand the impacts of climate change on the soil organic carbon storage in terrestrial ecosystems is of significance in predicting the changes of soil organic carbon in the future,and the interactions between terrestrial ecosystems and climate change.We presented the approaches of soil profile measurement,soil organic carbon modeling,and others to estimate the soil organic carbon storage in terrestrial ecosystems,and the uncertainty of these estimations.The research progress in understanding the effects of climate change on soil organic carbon storage in terrestrial ecosystems and the modeling of corresponding processes were reviewed,and the estimations of soil organic carbon storage changes under future climate changes were pointed out,with some questions in the estimations put forward.
URL [本文引用: 1]
To understand the impacts of climate change on the soil organic carbon storage in terrestrial ecosystems is of significance in predicting the changes of soil organic carbon in the future,and the interactions between terrestrial ecosystems and climate change.We presented the approaches of soil profile measurement,soil organic carbon modeling,and others to estimate the soil organic carbon storage in terrestrial ecosystems,and the uncertainty of these estimations.The research progress in understanding the effects of climate change on soil organic carbon storage in terrestrial ecosystems and the modeling of corresponding processes were reviewed,and the estimations of soil organic carbon storage changes under future climate changes were pointed out,with some questions in the estimations put forward.
DOI:10.1016/j.soilbio.2016.06.032URLPMID:27698513 [本文引用: 1]
When dry soils are rewetted a pulse of CO2 is invariably released, and whilst this phenomenon has been studied for decades, the precise origins of this CO2 remain obscure. We postulate that it could be of chemical (i.e. via abiotic pathways), biochemical (via free enzymes) or biological (via intact cells) origin. To elucidate the relative contributions of the pathways, dry soils were either sterilised (double autoclaving) or treated with solutions of inhibitors (15% trichloroacetic acid or 1% silver nitrate) targeting the different modes. The rapidity of CO2 release from the soils after the drying:rewetting (DRW) cycle was remarkable, with maximal rates of evolution within 6 min, and 41% of the total efflux over 96 h released within the first 24 h. The complete cessation of CO2 eflux following sterilisation showed there was no abiotic (dissolution of carbonates) contribution to the CO2 release on rewetting, and clear evidence for an organismal or biochemical basis to the flush. Rehydration in the presence of inhibitors indicated that there were approximately equal contributions from biochemical (outside membranes) and organismal (inside membranes) sources within the first 24 h after rewetting. This suggests that some of the flux was derived from microbial respiration, whilst the remainder was a consequence of enzyme activity, possibly through remnant respiratory pathways in the debris of dead cells.
DOI:10.1016/j.catena.2017.11.004URL [本文引用: 1]
URL [本文引用: 1]
With reference to the situation of nitrogen fertilization in 2003 and the recommendations from agricultural experts on fertilization to different crops, two scenarios, namely, ‘current situation’ and ‘fertilization as recommended’, were set for estimating the current and potential carbon sequestration of China’s cropland soil under nitrogen fertilization. After collecting and analyzing the typical data from the long-term agricultural experiment stations all over China, and based on the recent studies of soil organic matter and nutrient dynamics, we plotted China into four agricultural regions, and estimated the carbon sequestration rate and potential of cropland soil under the two scenarios in each province of China. Meanwhile, with the data concerning fossil fuel consumption for fertilizer production and nitrogen fertilization, the greenhouse gas leakage caused by nitrogen fertilizer production and application was estimated with the help of the parameters given by domestic studies and IPCC. We further proposed that the available carbon sequestration potential of cropland soil could be taken as the criterion of the validity and availability of carbon sequestration measures. The results showed that the application of synthetic nitrogen fertilizer could bring about a carbon sequestration potential of 21.9 Tg C·a-1 in current situation, and 30.2 Tg C·a-1 with fertilization as recommended. However, under the two scenarios, the greenhouse gas leakage caused by fertilizer production and application would reach 72.9 Tg C·a-1 and 91.4 Tg C·a-1, and thus, the actual available carbon sequestration potential would be -51.0 Tg C·a-1 and -61.1 Tg C·a-1,respectively. The situation was even worse under the ‘fertilization as recommended’ scenario, because the increase in the amount of nitrogen fertilization would lead to 10.1 Tg C·a-1 or more net greenhouse gas emission. All these results indicated that the application of synthetic nitrogen fertilizer could not be taken as a feasible measure for the carbon sequestration of cropland soil in China. Since synthetic fertilizer application is the basic guarantee of China’s crop production, it was suggested to increase the efficiency of synthetic nitrogen fertilizer, and at the same time, to cut down the synthetic nitrogen fertilizer production and its application on the premise that the crop yield should be ensured.
URL [本文引用: 1]
With reference to the situation of nitrogen fertilization in 2003 and the recommendations from agricultural experts on fertilization to different crops, two scenarios, namely, ‘current situation’ and ‘fertilization as recommended’, were set for estimating the current and potential carbon sequestration of China’s cropland soil under nitrogen fertilization. After collecting and analyzing the typical data from the long-term agricultural experiment stations all over China, and based on the recent studies of soil organic matter and nutrient dynamics, we plotted China into four agricultural regions, and estimated the carbon sequestration rate and potential of cropland soil under the two scenarios in each province of China. Meanwhile, with the data concerning fossil fuel consumption for fertilizer production and nitrogen fertilization, the greenhouse gas leakage caused by nitrogen fertilizer production and application was estimated with the help of the parameters given by domestic studies and IPCC. We further proposed that the available carbon sequestration potential of cropland soil could be taken as the criterion of the validity and availability of carbon sequestration measures. The results showed that the application of synthetic nitrogen fertilizer could bring about a carbon sequestration potential of 21.9 Tg C·a-1 in current situation, and 30.2 Tg C·a-1 with fertilization as recommended. However, under the two scenarios, the greenhouse gas leakage caused by fertilizer production and application would reach 72.9 Tg C·a-1 and 91.4 Tg C·a-1, and thus, the actual available carbon sequestration potential would be -51.0 Tg C·a-1 and -61.1 Tg C·a-1,respectively. The situation was even worse under the ‘fertilization as recommended’ scenario, because the increase in the amount of nitrogen fertilization would lead to 10.1 Tg C·a-1 or more net greenhouse gas emission. All these results indicated that the application of synthetic nitrogen fertilizer could not be taken as a feasible measure for the carbon sequestration of cropland soil in China. Since synthetic fertilizer application is the basic guarantee of China’s crop production, it was suggested to increase the efficiency of synthetic nitrogen fertilizer, and at the same time, to cut down the synthetic nitrogen fertilizer production and its application on the premise that the crop yield should be ensured.
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
[本文引用: 1]
DOI:10.1046/j.1365-2486.2003.00587.xURL [本文引用: 2]
DOI:10.1046/j.1365-2486.2003.00590.xURL [本文引用: 2]
