删除或更新信息,请邮件至freekaoyan#163.com(#换成@)

硅藻群落指示的近50年来大理西湖湖泊生态系统演变规律

本站小编 Free考研考试/2021-12-31

中文关键词大理西湖浅水湖泊硅藻群落稳态转换生态系统 英文关键词Lake Xihu, Dalishallow lakesdiatom communityregime shiftecosystem 中文摘要 近年来,增强的人类活动使得云南部分湖泊生态系统发生退化,由草型清水态向藻型浊水态转变.全球变化背景下,了解湖泊生态系统演变规律是进行有效管理的前提,具有重要的科学意义.本研究以云南大理州小型浅水湖泊西湖为例,通过对沉积物硅藻群落和理化指标的分析,探讨了20世纪60年代中期以来大理西湖环境演变历程.结果表明,大理西湖生态系统在近50年发生了明显的稳态转换,以2000年为节点,硅藻群落从2000年前偏好贫营养环境的底栖附生种Cocconeis placentulaStaurosira construensGomphonema angustumAchnanthidium minutissimum为优势种的状态,逐渐演替为偏好中营养环境的底栖附生硅藻Encyonopsis microcephalaNavicula cryptocephala及偏好富营养环境的浮游硅藻Cyclotella atomusCyclotella meneghinianaStephanodiscus hantzschiiAulacoseira granulata为主导的状态.时间序列的主成分分析表明,硅藻群落主要响应了营养的变化.冗余分析结果也证实营养盐富集是大理西湖硅藻群落长期演化的主要驱动因素.本文论述了近50年来大理西湖流域气候变化和开发活动(农业围垦、化肥施用、畜牧养殖和渔业养殖等)促使湖泊营养盐持续积累,浮游藻类大量繁殖,湖泊内部生产力显著提高,湖泊生态系统逐渐向藻型浊水态转变的演化特征. 英文摘要 In recent decades, intense human activities have caused a decline in many lake ecosystems in Yunnan Province, rendering the transformation of the lake from a clear macrophyte-dominated state to a turbid phytoplankton-dominated state. Improved understanding of the ecological changes in lake ecosystem has significant implications for management. In this study, a small lake in Dali Prefecture of Yunnan Province, i.e., Lake Xihu, was selected. Combined with diatom records and physicochemical proxies from the lake sediments, this paper focuses on the long-term ecological changes in Lake Xihu, Dali since the mid-1960s. The results show that the Lake Xihu, Dali has undergone a significant shift in stable states over the past 50 years. Prior to 2000, the benthic-epiphytic species (i.e., Cocconeis placentula, Staurosira construens, Gomphonema angustum, and Achnanthidium minutissimum) dominated in diatom assemblages, indicating oligotrophic conditions; since 2000, benthic-epiphytic species (i.e., Encyonopsis microcephala and Navicula cryptocephala) and planktonic species (i.e., Cyclotella atomus, Cyclotella meneghiniana, Stephanodiscus hantzschii, and Aulacoseira granulata) dominated successively, indicating mesotrophic to eutrophic conditions. Principal component analysis based on the diatom assemblages in temporal scale showed the response of diatoms succession to nutrients. Redundancy analysis also confirmed that nutrient enrichment was the main driving force for the succession of diatom assemblages in Lake Xihu, Dali. In the past 50 years, climate change and human activities (i.e., agricultural reclamation, fertilization, animal husbandry, and fishery) have enhanced the accumulation of nutrients in the lake. The continuous loading of nutrients promoted the propagation of planktonic algae, and also the productivity of the lake, rendering the transformation to a turbid phytoplankton-dominated state.

PDF全文下载地址:

https://www.hjkx.ac.cn/hjkx/ch/reader/create_pdf.aspx?file_no=20201024&flag=1&journal_id=hjkx&year_id=2020

相关话题/环境 实验室 中国科学院 南京地理与湖泊研究所 安徽师范大学

鐎殿喒鍋撻梺顐g濠€鎵博濮楃P闁挎稒鐭粩瀛樼▔閸モ晩娼氶柤鏉垮暟閻栫儤绋夐幘鑼懝閻犲洦宕橀~瀣紣閹达附顓瑰〒姘虫硶濠€鍛存晬鐏炲墽妲ㄩ柡鍫厸缁楀宕氭0浣侯伇闁告帒妫濋幐鍫曟晬娴h櫣鍗滈悗鐢垫嚀閸ㄦ繄绮诲Δ瀣<
547闁圭鍋撻梻鍕╁灪閻楀酣鎳撻崘顏嗗煛闁兼澘鍟畷锟�1130缂佸绉电€垫氨鈧纰嶉弳鈧柡澶嬪姉濞堟垿宕¢崘褏绋囩紒澶婄Ч閸樸倖绺藉Δ鍜佹毌閹煎瓨鎸堕埀顑挎祰椤锛愰幋顖滅婵炴垹鏁稿ú濠囨嚐鏉堫偒鍤旈柕鍡曡兌缁€趁规惔娑掑亾娴g晫妲堥柛鎺撴偠閳ь兛绶氶崳楣冩懚瀹ュ啠鍋撴担鐑樺€炵€规悶鍎埀顑胯兌椤撴悂鎮堕崱鎰ㄥ亾娴f亽浠﹀ù鍏煎搸閳ь兛娴囬崒銊﹀濮樸儮鍋撴担瑙勬畬闁煎弶褰冪缓楣冩偠閸℃劏鍋撴担鐤幀闁哄倸娲㈤埀顑挎祰婢规捇寮甸妯峰亾娴h鐓€闂傚倽顔婄槐鍫曞箻椤撴壕鍋撴担鍦€婇悗娑宠礋閳ь兛绀佺亸鎵偓娑宠礋閳ь兛娴囬鍝ョ不濡や焦绨氶柕鍡曠瀹稿宕g仦鍌楀亾娴e憡鍕鹃柣鐐叉閳ь兛鐒﹂弬鍌氣柦濮瑰洠鍋撴担鍛婃噸閻庢冻璐熼埀顑挎缂嶅鎳栭懠顒冾潶缂佹冻鎷�28缂侇偉顕ч鐔虹矓閹搭垳纾�