关键词:农药施用行为;农户;环境友好;影响因素;Meta分析 Abstract The main purposes of this study were to reveal key factors influencing farmers’ pesticide application behavior, and reasons for differences in research level. A total of 43 papers were selected from China and abroad. We explored the following issues: whether key factors in pesticide application in China are completely homogeneous; key factors influencing the application of pesticide in farmers under the condition of allowing the existence of heterogeneity; and trends in key factors over time. The meta-analysis method includes effect size selection, fixed or random effect model selection depending on the existence of heterogeneity, publication bias tests and correction, sensitivity analysis, cumulative meta-analysis and meta-regression analysis. The Q statistic was used to test whether there was heterogeneity. If variables are homogeneous in farmers, the fixed effect model is used, if variables are heterogenous, then the random effect model is used. Results showed that farmers’ pesticide application behavior was not completely homogeneous. There was significant heterogeneity among age, household income, knowledge of pesticide use, scale of cultivation and ratio of agricultural income. The key factors influencing behavior included gender, educational level, risk appetite, knowledge of pesticide use, farming experience, proportion of agricultural income, pesticide application training and pesticide residue detection. The trend in educational level, risk appetite, pesticide related knowledge, participation in pesticide application technical training and government propaganda support increased over time. However, variables including gender and agricultural income accounted for a significant impact, while the trend was nearly stable. The remaining variables gradually decreased. Based on these results, two suggestions spanning policy and academic are proposed.
注:NS为Trim and Fill非参数校正填补文献的数量;SEN为NS的标准误。 新窗口打开 (1)个体特征。性别对农户环境友好型农药施用行为具有显著的负向影响,与女性相比,男性更倾向采用不利于环境的农药施用行为;年龄存在发表偏倚,漏斗图右侧填补12篇文献,校正后仍不显著,可能意味着年龄的影响并非是线性的;年龄存在显著的异质性,此处暂不讨论;教育程度越高的农户,越可能出现环境友好型的农药施用行为;风险厌恶者更担心病虫害等带来的损失,对环境友好型农药施用有显著负向影响。 (2)家庭特征。家庭人口数、家庭年收入和劳动力人数对农户环境友好型农药施用行为均不产生显著性影响。其中家庭人口数不显著的原因可能是该变量并不能真实反映农户家庭生存压力,即家庭人口数越多并不意味着需要赡养或抚养人口越多;此外,随着农民收入的多元化和农业副业化,农业本身可能并不是农户家庭主要收入来源,故对农户农药施用行为不产生显著性影响。家庭年收入的多寡并不能反映农户是否以农业为主要收入来源,这也可能是导致该变量不显著的主要原因,其异质性的原因后文讨论。劳动力人数影响不显著的原因可能是:一方面目前农业生产仍主要依靠现代农业生产要素的投入,劳动力对农药施用的反向替代作用有限;另一方面中国农户年龄仍普遍较大,受劳动能力和教育程度限制,对环境友好型农药施用方式选择并无倾向。 (3)认知特征。对环境污染和人体健康影响的认知并不显著影响农户农药施用行为,在一定程度上也反映出目前较多农户的农业环境保护意识、农药施用对自身健康的影响关注不足,这一点也可在农户对农药知识的了解中得到验证。对农药知识了解越多,越能显著促进农户合理施药,且该变量影响较大。 (4)种植特征。种植规模存在发表偏倚,倒漏斗图左侧填补7篇文献,校正后呈现显著的异质性,仍未对农户农药施用行为产生显著影响,且其效应极小,在目前仍以小农生产为主要经营特征的中国农村地区,大规模种植相对较少,每户种植面积差异不大,这也可能是该变量不显著的重要原因。种植年限与预期一致,传统的农药施用方式等种植习惯较难改变,对农户环境友好型农药施用具有显著的负向影响。农业收入占比存在显著的异质性,该变量越高,意味着农户家庭收入来源更加依赖农业,为防范风险带来的损失更倾向出现不合理的农药施用行为。安全农产品的价格预期对农户环境友好型农药施用行为无显著影响,可能的原因是目前中国通过认证进行销售的农产品有限,多数农产品未通过认证,单个农户即便生产出安全农产品也无法通过有效的途径通向目标市场,受市场信息渠道等多方面因素制约,农户的预期很难转变为实践。 (5)外部条件。参加农药施用技术培训的农户更清楚农药施用流程及高毒农药等带来的危害,会显著提高环境友好型农药施用行为。是否参加合作社对农户农药施用行为无显著影响,可能因为并非所有合作社都起到了规范农户施药行为的作用。是否有农药残留检测存在发表偏倚,校正后仍对农户农药施用行为具有显著正向影响,且这一政策的刚性要求对农户农药施用行为具有较强的约束力。农业生产过程检测和政府宣传支持并未产生显著性影响,一方面表明了农业生产过程难以检测和检测成本高的特征,另一方面也反映出目前政府对农户环境友好型农药施用方式的引导不足。
5.2 敏感性分析
为验证上文分析结果的稳健性,采用Leave one out方法和径向图对数据分析结果进行检验,由于分析结果过多,Leave one out结果从略,仅以一个显著性因素和一个非显著性因素径向图为代表进行说明(图2,见81页)。图中的点代表模型拟合的残差,横轴标准误倒数表示研究精度,从纵轴Z统计量的零点出发,通过图中残差点形成的射线投射到右侧弧线对应的值为该残差点对应的实际观测值,即效应量。 显示原图|下载原图ZIP|生成PPT 图2敏感性分析径向分布 -->Figure 2Sensitivity analysis with radial distribution -->
由图2(见81页)分析可知,教育程度和家庭年收入效应量的Z统计量均围绕零刻线上下均匀分布,且没有明显的趋势变化;此外,Leave one out分析结果表明,每移除一篇文献后效应量显著性、置信区间、异质性检验结果和发表偏倚检验结果均未发生显著性变化。由此推断5.1章节中分析结果具有较强的稳健性。
在中国农户范围内,影响农户环境友好型农药施用行为的关键因素是完全同质的吗?本文的回答是否定的。年龄、家庭年收入、对农药知识的了解、种植规模和农业收入占比具有显著异质性。年龄的异质性源于研究区域和研究方法的差异;家庭年收入的异质性是因为抽样时间、期刊来源、期刊影响因子、研究区域、研究方法和因变量类型的不同;对农药知识了解的异质性原因是抽样时间的不同;种植规模的异质性可能是农户种植类型的差异所致;农业收入占比的异质性来源为变量测量方式和研究方法。允许异质性存在的条件下,影响农户环境友好型农药施用行为的关键因素为农户性别、教育程度、风险偏好、对农药知识的了解、种植年限、农业收入占比、是否参加过农药施用培训和是否有农药残留检测。随时间推移,受教育程度、风险偏好、对农药知识的了解、是否参加农药施用培训和政府宣传支持对农户施药行为影响强度有增加的趋势;性别和农业收入占比影响显著且趋势较为稳定;其余变量的影响均不同程度的减弱。 针对上述分析结果提出两个层面的建议: (1)政策层面。①通过正式或非正式教育加强对农业生产者尤其是男性的农药施用知识和技术的培训;②完善农村农业保险体系,增强农户风险抵御能力;③拓宽农户收入渠道,逐步降低部分依农为生的农户对农业收入的依赖;④进一步强化农业合作社等农村基础性组织的监管,确保其能真正为农户提供生产性帮助和支持。促进农户逐步向环境友好型农药施用方式转变。 (2)研究层面。①由于影响农户施药行为的影响因素在中国范围内并非完全同质,因此在农户个体层面的抽样调查中有必要将农户细分,如按其种植类型、年龄段等特征进行分类,进一步详细考察农户施药行为的特征;②加强不同群体、不同地区等影响农户施药行为关键因素的差异分析,更为细致的差异不应仅归为地区差异;③方法的选择会影响分析的结果,在今后的研究中应注意不同方法的交叉和比较运用,对同一问题的分析可采用多方法比较分析,得出更稳健的结论;④随时间的发展,影响农户施药行为的关键因素及强度在不断变化,今后的研究设计应更多的以半开放或开放式问卷为基础,从农户角度阐述对其施药行为具有影响的关键因素,避免封闭式问卷所带有的研究者更强的主观倾向;⑤变量的测量应进一步结合统计学方法,以尽可能实现所测变量携带更多的信息;⑥对农户农药施用行为的分析中,应将意愿和真实行为加以区分。 致谢:非常感谢表1第一作者及共同作者为本研究提供的数据支撑;特别感谢匿名审稿专家和责任编辑的宝贵意见,文责自负。 The authors have declared that no competing interests exist.
Fan LX, Niu HP, Yang XM, et al. Factors affecting farmers' behaviour in pesticide use: Insights from a field study in northern China [J]. , 2015, 537: 360-368. [本文引用: 2]
[2]
ZhangF, ChenX, VitousekP.Chinese agriculture: an experiment for the world [J]. , 2013, 497(7447): 33-35. [本文引用: 1]
[3]
Wang YQ, WangY, Huo XX, et al. Why some restricted pesticides are still chosen by some farmers in China? Empirical evidence from a survey of vegetable and apple growers [J]. , 2015, 51: 417-424. [本文引用: 2]
[4]
Kruger DJ, Polanski SP.Sex differences in mortality rates have increased in China following the single-child law [J]. , 2011, 2(1): 1-4. [本文引用: 1]
SchreinemachersP, ChenH, Nguyen T T L, et al. Too much to handle? Pesticide dependence of smallholder vegetable farmers in Southeast Asia [J]. , 2017, 593: 470-477. [本文引用: 1]
[MaoF, Kong XZ.Analysis on the influencing factors of farmers' safety pesticide matching behavior-based on the investigation of 5 major apple county in Shaanxi Province [J]. , 2011, (5): 4-12. ] [本文引用: 3]
[Cai YY, Yu LL.Ecological compensation for agricultural land in the key development area of Wuhan based on the willingness of farmers [J]. , 2014, 36(8): 1660-1669. ] [本文引用: 1]
[Hu DH, Chen ZG, Sun QZ, et al. Impact of contract production mode on farmers' income and food safety: a case study of apple industry in Shandong province [J]. , 2006, (11): 17-24. ] [本文引用: 2]
[Jia XL, Dong HR, Qi LL, et al. Study on using pesticide behavior of the vegetable growers-in Hebei province [J]. , 2011, 31(3): 266-270. ] [本文引用: 2]
[15]
Jallow M FA, Awadh DG, Albaho MS, et al. Pesticide risk behaviors and factors influencing pesticide use among farmers in Kuwait [J]. , 2017, 574: 490-498. [本文引用: 1]
Gong YZ, BaylisK, KozakR, et al. Farmers’ risk preferences and pesticide use decisions: evidence from field experiments in China [J]. , 2016, 47(4): 411-421. [本文引用: 2]
[Wang CW, Gu HY.The market vs. the government: What forces affect the selection of amount of pesticide used by China’s vegetable grower? [J]. , 2013, (11): 50-66. ] [本文引用: 2]
[RenZ, Xue XL.Analysis on the will of the nonpollution pesticide use and its influencing factors-an empirical study based on 609 farmers [J]. , 2016, 30(7): 31-36. ] [本文引用: 2]
[Li XY, Guan ZQ.Analysis on the safety behavior in pesticide application and its influencing factors-a case study of Anxi tea farmers, Fujian [J]. , 2013, 23(6): 84-93. ] [本文引用: 2]
[Niu YL.The analysis on farmers’ quality and safety control behavior and its influencing factors in “farmer-supermarket direct purchase”-based on the survey from 484 farmers in Liaoning province [J]. , 2014, 32(2): 236-241. ] [本文引用: 2]
[23]
MorrenM, GrinsteinA.Explaining environmental behavior across borders: a meta-analysis [J]. , 2016, 47: 91-106. [本文引用: 1]
[24]
Hunter JE, Schmidt FL.Methods of Meta-analysis: Correcting Error and Bias in Research Findings [M]. , 2004. [本文引用: 1]
[25]
Lipsey MW, Wilson DB.Practical Meta-analysis [M]. , 2001. [本文引用: 1]
[26]
PigottT.Advances in Meta-analysis [M]. , 2012. [本文引用: 1]
[27]
FrancoA, MalhotraN, SimonovitsG.Publication bias in the social sciences: unlocking the file drawer [J]. , 2014, 345(6203): 1502-1505. [本文引用: 1]
[28]
Moreno SG, Sutton AJ, Ades AE, et al. Assessment of regression-based methods to adjust for publication bias through a comprehensive simulation study [J]. , 2009, 9(2): 1-17. [本文引用: 1]
[29]
Rothstein HR, Sutton A J. Borenstein M.Publication Bias in Meta-analysis: Prevention, Assessment and Adjustments [M]. , 2006. [本文引用: 1]
[30]
Wallace BC, Schmid CH, LauJ, et al. Meta-analyst: Software for meta-analysis of binary, continuous and diagnostic data [J]. , 2009, 9(1): 1-12. [本文引用: 1]
[31]
LauA, Li KY, Yang WF, et al. Induction chemotherapy for squamous cell carcinomas of the oral cavity: a cumulative meta-analysis [J]. , 2016, 61: 104-114. [本文引用: 1]
[Zhang HJ, ZhouJ, He ML, et al. Factors affecting the use of pollution-free or green pesticide in vegetable growers-based on the investigation of vegetable growers in Shandong province [J]. , 2016, (4): 27-29. ] [本文引用: 1]
[Zhang FH, Hu JL.Analysis of workable mechanism on behavior of fruit grower planting pollution-free and high-quality apple based on the theory of planned behavior: Evidence from field investigation of apple growers from 16 cities in Shandong province [J]. , 2013, 34(7): 48-55. ] [本文引用: 1]
[Fang QP, Dai YY, XuX.On moral hazard of security vegetable produces from organizational perspective: Taking Jiangsu province as an example [J]. , 2011, 11(1): 44-50. ] [本文引用: 1]
[Wang HL, YangS, Xu XH, et al. Analysis on the farmers’ cognition and planting willingness on the quality safety of rice in Jilin province [J]. , 2014, 39(6): 76-80. ] [本文引用: 1]
[Li HM, Fu XH, Wu XM.The willingness of farmers’ safe application of pesticides and its influencing factors-Investigation and analysis of 214 farmers in Guanghan city, Sichuan province [J]. , 2007, (5): 99-104. ] [本文引用: 1]
[Wang ZG, Yao YY, XuX.Farmers’ willingness to pay for bio-pesticides: Based on the survey conducted in Laiyang, Laizhou, and Anqiu in Shandong province [J]. , 2012, 22(S1): 54-57. ] [本文引用: 1]
[Lou BJ, SongM, Zhang QW, et al. Factors affecting the behavior of farmers’ highly pesticide application-taking the six provinces in eastern China as an example [J]. , 2014, (7): 108-112. ] [本文引用: 1]
[ZhuD, KongX, Gu JP.Irrational equilibrium of farmers' excessive application of pesticides: evidence from farmers in southern China [J]. , 2014, (8): 17-29. ] [本文引用: 1]
[Qiao LJ, WangJ, LiX.Analysis on impact factors of the risk perception and aversion will of farmers’ pesticide use behavior [J]. , 2014, 42(3): 237-241. ] [本文引用: 1]
[TianY, Zhang JB, HeK, et al. Analysis on low-carbon production behavior of farm households and its influencing factors-taking fertilizer application and pesticide use as an example [J]. , 2015, (4): 61-70. ] [本文引用: 1]
[Fu XH, Song WT.Analysis on the factors affecting the purchase intention and behavior of farmers’ biological pesticide-taking Sichuan province as an example [J]. , 2010, (6): 120-128. ] [本文引用: 1]
[Jiang JY, Ke MF, Zhang SY, et al. Analysis on the influencing factors of farmers’ quality control of vegetable quality-based on 151 farmers in Gaocheng city, Hebei province [J]. , 2012, (5): 35-42. ] [本文引用: 1]
[CaiR, Han HY.Impact of cooperative on farmers’ pesticide application behavior and its influence mechanism: an empirical analysis based on the survey data of apple growers in Shandong province [J]. , 2012, 17(5): 196-202. ] [本文引用: 1]
[Wu LH, Zhang XL, Shan LJ, et al. The impact of economic and social characteristics of scattered farmer household on pesticide application behavior: the case in Henan province [J]. , 2011, 33(3): 60-68. ] [本文引用: 1]
[Xing YH, ZhaoH, Su XD, et al. Impact factors on behavior of using pesticide in greenhouse vegetable growers in Qinghai [J]. , 2014, 4(4): 340-343. ] [本文引用: 1]
[Wang ZG, Li TF.A study on farmers’ cognitive of food safety regulation and their decision-making behavior of pesticide use in the export-oriented vegetable production area [J]. , 2012, 22(2): 164-169. ] [本文引用: 1]
[Cai SK, LiJ.Pesticide application intensity by farmers and its influences-based on the investigation data of farmers from major grain producing areas [J]. , 2011, 44(11): 2403-2410. ] [本文引用: 1]
[Zhao LG, Cai SK.Analysis of pesticide cost savings and grain yield increased by IPM technology in late rice farmers [J]. , 2013, (5): 78-87. ] [本文引用: 1]
[Li GS, Zhu LL, MaL.The impact of pollution-free agricultural products certification on farmers' pesticide use-a case study of Nanjing, Jiangsu province [J]. , 2007, (5): 95-97. ] [本文引用: 1]
[Qian YX, YangR, ZhaoW, et al. Analysis on influential factors of Chinese medicinal herb growers’ willingness to use green pesticides: Evidence on panax notoginseng production areas in Wenshan, Yunnan province [J]. , 2013, 38(20): 3453-3457. ] [本文引用: 1]
[ZhouF, XuX.Analyzing moral hazard behaviors of non-environmental pollution agri-product producers under the government regulation-Based on a survey of rural households in Jiangsu [J]. , 2007, (4): 25-31. ] [本文引用: 1]
[Gao CX, WangM, YeT, et al. Analysis on the differences between planting behavior and insurance decision-making among farmers with different income [J]. , 2013, (10): 46-55. ] [本文引用: 1]
[60]
Li DP, NansekiT, TakeuchiS, et al. Farmers’ behaviors, perceptions and determinants of pesticides application in China: evidence from six eastern provincial-level regions [J]. , 2012, 57(1): 255-263. [本文引用: 1]
[61]
Zhou JH, Jin SS.Safety of vegetables and the use of pesticides by farmers in China: evidence from Zhejiang province [J]. , 2009, 20(11): 1043-1048. [本文引用: 1]