重庆渝北地区表层土壤硒含量分布与农业经济意义

通过对重庆渝北地区表层土壤网格化取样分析及岩、土、植物样的分析评价,阐述了Se元素的含量水平、空间分布与农业经济意义,并编制富硒土壤分布图。研究区表层土壤Se背景平均值为0.205mg.kg-1。土壤Se分布主要受地层、岩性及土壤对Se元素富集特性的控制。区内富硒土面积208.25km2,占全区11.57%,足硒土面积576km2,占全区32%。最具开发潜力的富硒土区为"北碚天府-工农-代家沟"一带(Ⅰ区),面积为36.8km2,富、足硒土次之(Ⅱ、III区),面积为110.3km2。富硒土区白菜、卷心菜等十字花科作物,水稻、玉米等粮食作物为富硒无公害或绿色农产品,具较大的农业经济意义。

The Contents and Distribution of Selenium in Topsoils in Yubei District, Chongqing City and Its Agroeconomic Significance

The contents and distribution of selenium(Se) in the topsoils in Yubei district,Chongqing City and its agroeconomic significance were investigated,and the Se-rich soil distribution chart was drawn,according to the evaluation of the topsoil,rock,soil and vegetable.The average value of Se in the tested area was 0.205 mg·kg-1.The distribution of Se was controlled by the strata,lithology and the characteristics of soil concentration.The Se-rich topsoils covered an area of 208.25 km2(11.57%) while the Se-abundance topsoils,576 km2(32%).According to the contents of Se,the tested area was divided into 3 regions: I,II and III.Region I,that is "Beibei-Tianfu-Gongnong-Daijiagou",was the most potential development Se-rich topsoil and it covered an area of 36.8 km2,followed by region II and region III(110.3 km2).Many vegetables and cereals in region I,such as cruciferae(for example Chinese cabbage,cabbage etc.),rice and maize and so on,were the Se-rich green food and nuisance-free agricultural products.And they have immense agro-economic significance.