湘中典型稻田系统Cd平衡分析  

Cd Balance Analysis of a Typical Rice Paddy System in Central Hunan

作　　者：蒋凯 邓潇 周航[1,2] 龙坚 李欣阳[1,2] 董霞 王树兵 刘文辉 侯红波 彭佩钦 廖柏寒 JIANG Kai;DENG Xiao;ZHOU Hang;LONG Jian;LI Xin-yang;DONG Xia;WANG Shu-bing;LIU Wen-hui;HOU Hong-bo;PENG Pei-qin;LIAO Bo-han(College of Environmental Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Hunan Engineering Laboratory for Control of Rice Quality and Safety,Central South University of Forestry and Technology,Changsha 410004,China;Agricultural Integrated Service Center of Changsha County,Huangxing Town,Changsha 410100,China;Agricultural Integrated Service Center of Ningxiang City,Shuangjiangkou Town,Changsha 410601,China)

机构地区：[1]中南林业科技大学环境科学与工程学院,长沙410004 [2]中南林业科技大学稻米品质安全控制湖南省工程实验室,长沙410004 [3]长沙县黄兴镇农业综合服务中心,长沙410100 [4]宁乡市双江口镇农业综合服务中心,长沙410601

出　　处：《环境科学》2019年第7期3324-3330,共7页Environmental Science

基　　金：国家科技支撑计划项目(2015BAD05B02);农业部财政部重大专项(农办财函[2016]6号);湖南省重点学科建设项目(2006180)

摘　　要：运用大田定位试验的方法,研究了典型稻田系统Cd污染发展趋势.于2015-11~2018-11逐月采集大气沉降及灌溉水样,同时多次采集肥料、土壤及水稻样,监测分析样品中Cd含量,研究湘中典型稻田系统Cd输入输出平衡情况.结果表明,稻田系统Cd通过灌溉水、大气沉降和肥料等途径输入,年均输入量为8.735 g·(hm^2·a)^-1,其中大气沉降为主要来源,占总输入的69.15%~82.04%,平均为76.61%,其次是灌溉水占12.62%~23.66%,平均为16.94%,肥料占5.34%~7.19%,平均为6.45%;稻田系统Cd通过地表径流、土壤下渗和水稻地上部分收获途径输出,年均输出量为7.093g·(hm^2·a)^-1,水稻地上部分收获占总输出的85.27%~95.02%,平均为89.69%,其次是地表径流4.57%~13.96%,平均为9.41%,土壤下渗输出的Cd最少,为0.41%~1.51%,平均0.90%.结果表明,研究区稻田系统Cd为净输入,土壤Cd污染形势仍在加剧.稻草还田与稻草移除将对土壤Cd平衡产生重要影响,稻草移除可以减缓土壤Cd污染发展趋势.By conducting field positioning experiments,we studied the development trend of Cd pollution in a typical paddy system.The samples of atmospheric deposition and irrigation water were collected monthly from November 2015 to November 2018 during which fertilizer,soil,and rice samples were also collected. The Cd concentration in the samples was monitored and analyzed to conduct research on the balance between Cd inputs and outputs in a typical paddy system in Hunan Province. The results suggest that through irrigation water, atmospheric deposition and fertilizer, the average annual input of Cd in the paddy field system is 8. 735 g·( hm^2·a)^-1,of which atmospheric deposition,the major source,accounts for 69. 15%-82. 04% of the total input,with an average of 76. 61%. This is followed by irrigation water and fertilizer,respectively,accounting for 12. 62%-23. 66% and 5. 34%-7. 19%,with an average of 16. 94% and 6. 45%,respectively. Through surface runoff,soil infiltration and the rice harvest of the aboveground portion,the annual average output of Cd contained in the paddy system is 7. 093 g·( hm^2·a)^-1. Rice harvest accounts for 85. 27%-95. 02% of the total output,with an average of 89. 69%;surface runoff accounted for 4. 57%-13. 96% of the total output,with an average of 9. 41%;and soil infiltration accounted for 0. 41%-1. 51% of the total output,with an average of 0. 90%. The study indicates that Cd contained in paddy systems in Central Hunan exhibits a net input,and the soil Cd pollution is increasing as a result.Straw returning and straw removal have an important impact on the soil Cd balance,and straw removal can slow the trend of soil Cd pollution accumulation.

关 键 词：稻田土壤 CD污染 大气沉降 水稻 Cd平衡 

分 类 号：X171.5[环境科学与工程—环境科学]