摘要
为了研究并评价中南丘陵区林地-稻田复合生态系统稻田表面水的环境质量效应,以河滨平原稻田为对照,于2013年4月中旬到9月上旬对湘北汩罗市桃林林场两类林-稻(松-稻、混-稻)系统稻田进行表面水原位研究,基于不同时期各系统稻田表面水总氮、总磷、NO-3-N、NH+4-N、有机氮、水溶性有机碳(DOC)、颗粒有机碳(WPOC)、COD、总Pb、总Cd、pH等指标的监测结果,用通径分析法研究了不同林-稻系统稻田表面水的环境机制,同时用模糊数学综合评价法对稻田表面水质量进行了评价。结果表明:(1)在非稻季,人为干扰少的混-稻系统稻田表面水污染风险低于松-稻系统及对照,其中前者稻田表面水属Ⅲ类水,后两者表面水属Ⅴ类水;(2)在稻季,两类林-稻系统稻田表面水水质优于对照,前者稻田表面水平均总氮、COD、总Cd、总Pb含量仅分别是对照的75.0%,78.4%,62.6%,87.6%。在研究中发现,稻田表面水有机质依循"生物有机质→胶体有机质→颗粒有机质→稻田土壤"途径循环转化;稻田表面水颗粒有机质含量规定了稻田表面水85.7%的COD和77.3%的镉、76.2%的铅,是影响稻田表面水质量的关键因素。综上所述,丘陵林-稻复合系统稻田表面水质量优于平原区,林-稻复合系统具有阻断污水灌溉、屏蔽病虫传播的环境优势;稻田表面水水质受水体有机质循环机制调节。
In order to study and evaluate the quality effect of paddy surface water in forest-paddy field systems,an investigation was conducted by in-situ field experiment in paddy of two types of forest-paddy field systems（Pinus elliotti land-paddy and mixed forest-paddy system）in Taoling forest farm,with contrast in paddy of riverside plain,in Minuo municipal,northern Hunan province,from mid April to early September in 2013.Based on the monitoring results of the contents of total N,total P,NO-3-N,NH＋4-N,DON,DOC,WPOC（water particle organic carbon）,COD,total Cd,total Pb,and pH of the paddy surface water from the study sites,the environmental mechanism of paddy field water was researched by path coefficient analysis,and the quality of paddy surface water was evaluated via a method of fuzzy comprehensive evaluation.The results showed：（1）The water＇s risk of being polluted in mixed forest-paddy system was lower than that in elliotti land-paddy and the contrast,with the paddy surface water in the former being classified into the Ⅲ grade of surface water,while that in the latter two into the Ⅴduring no cropping season.（2）The quality of paddy surface water in the two types of forest-paddy systems was better than that in the contrast,with the mean contents of total N,COD,total Cd,and total Pb of paddy surface water in the former only being 75%,78.4%,62.6%,and 87.6% of that in the contrast during cropping season.In the research,our finding showed that the water organic transformed carbon cycling as a way as ＂bioorgarnicmatter→ colloidal organic matter→ particulate organic matter→ paddy soil＂,and the particulate organic matter was the key factor of the water quality with dominating 85.7% COD,77.3% Cd,and 76.2% Pb in paddy surface water.In conclusion,the quality of paddy surface water in forest-paddy field systems was superior to that in plain paddy field due to the former systems being separated from sewage irrigation and shielding pests and disease from outside;also,the quality of paddy surface w
出处
《水土保持学报》
CSCD
北大核心
2015年第1期268-273,278,共7页
Journal of Soil and Water Conservation
基金
林业公益性行业科研专项(201404316)
湖南省高等学校科学研究项目(12C0457)
关键词
丘陵区
林-稻系统
稻田表面水
环境机制
质量效应
hilly regions
forest-paddy systems
paddy surface water
environmental mechanisms
quality effect
