Investigations on Nitrate Pollution of Soil, Groundwater and Vegetable from Three Typical Farmlands

来源 :中国农业科学(英文版) | 被引量 : 0次 | 上传用户:Whoafraidwh0
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The aim of this study was to determine the nitrate pollution status of soil, groundwater, and vegetable from three typical farmlands (croplands, vegetable fields, and orchards) in Beijing region. During the investigation, hundreds of the soil,groundwater, and vegetable samples from three typical farmlands were collected and analyzed. In addition, attributes of all samples were recorded for data analysis. The results showed that nitrate was substantially accumulated in soil profiles,while the soil nitrate concentrations of vegetable fields and orchards were higher than those of croplands. Nitrate concentration in 0-30 cm soil of vegetable field and orchard were 3.8 and 1.2 times of that of cropland, respectively. Nitrate content of groundwater in vegetable field was 13.8 mg L-1 (with the over-standard ratio 44.8%), which was 2.8 folds of that in cropland. Nitrate concentration of groundwater under orchard was 9.3 mg L-1 (with the over-standard ratio 23.5%),which was 1.9 folds of that in cropland. High concentrations of the nitrate in vegetables were detected, particularly green leafy vegetables ranked first with 2 685.5 mg kg-1, followed by rhizome vegetables, cabbages, and fruit vegetables. The nitrate over-standard ratios of rhizome vegetables, green leafy vegetables, fruit vegetables, and cabbages were 80.9, 37.9,29.7, and 2.2%, respectively. The results revealed that the high nitrate concentrations of soil, vegetable, and groundwater might result from the high fertilization dose.
其他文献
将纯化后的多壁碳纳米管与铝粉按质量比1∶5混合球磨后压制成块,待合金熔化后,将碳纳米管预制块直接加入铝合金熔体,然后用叶片搅拌器分别搅拌1、2、3、5、10 min后取出合金
本文对龙泉市生态公益林建设目前存在的主要问题作了较详细的阐述,并对解决存在的主要问题作者提出了思考与建议.
钢筋挤压连接技术是一种粗钢筋连接的新工艺新方法.介绍了原有钢筋挤压机的液压系统存在的种种问题,提出了用增压型钢筋挤压连接系统代替原有的超高压系统,改进后的突出优点
文章以工程实例为基础,阐述了现代测量技术在违法占地测绘中的施测方法。对于国土部门掌握违法用地情况,从而对责任单位和责任人做出行政处罚的提供了有力证据。方法的采用,使得数据更加准确,做到有的放矢。
本文论述了科研服务背景下,图书馆延伸学术会议服务的必要性和可行性,同时结合高校图书馆职能和具备的条件,提出学术会议服务形式与内容的构想,并对其影响进行了探讨。 This
文章介绍园区经济和图书馆联盟的定义及其相关情况,以晋陕豫黄河金三角“国家承接产业转移示范区”为例,探讨创新建立基于园区经济服务的图书馆联盟的意义、宗旨和目标任务;提
The current financial crisis is an inevitable result of the financial system accommodating a new banking business model,which endeavors to benefit,with increase
文章论述了21世纪我国区域图书馆联盟产生的背景,对区域图书馆联盟的多元化发展作了初步研究,包括体制的多元并存,规模的大小差异,路径的不同选择,组织的多样化模式等,并对区
简要介绍了GPS-RTK高程拟合原理,及GPS-RTK区域水准拟合在肥东小水库测量中的应用,并对其测量数据进行了精度分析.通过实例证明:动态RTK测量同样在地形起伏较小的地[X能达到
为了规范农村公路资金来源与使用,从农村公路资金来源的规范性和事权与财权的匹配性角度分析,指出县乡地方政府作为农村公路投资主体已经成为资金瓶颈,因此建立统一的专项基