不同利用强度下绿洲农田土壤微量元素有效含量特征

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 不同利用强度下绿洲农田土壤微量元素有效含量特征 DOI: 10.5846/stxb201101280146 作者: 作者单位: 中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所,中国科学院新疆生态与地理研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点基础研究发展计划项目(2009CB421302); 国家自然科学基金项目(41001171) The availability of trace elements in an oasis soil under different utilization intensity in an arid area in China Author: Affiliation: Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以地处极端干旱背景下的塔里木盆地南缘策勒绿洲为研究区,以绿洲化为视角,根据当地农民耕作习惯于2005年选择4块试验农田,分别代表当地典型的农田利用强度。基于单项指数 (Ei)和综合指数 (Ec)相结合的评价方法,分析了绿洲农田在不同利用强度下的土壤Fe、Cu、Mn、Zn等微量元素有效性,探讨了土壤微量元素与人为耕作管理措施之间的关系。结果表明:人为耕作管理强度会对土壤微量元素有效含量产生重要影响,绿洲不同位置农田因施肥强度和管理方式的差别,其土壤微量元素有效含量特征存在显著差异。绿洲内部农田土壤有效Fe、Cu、Mn、Zn含量显著高于绿洲边缘各样地,新垦农田土壤有效Fe、Cu、Zn含量均低于对照样地;绿洲内部农田土壤微量元素有效性最高,新垦农田最低;农田土壤微量元素有效性与土壤有机质存在显著的正相关关系。 Abstract:Trace elements are important components of soil and their characterization is necessary for determining soil quality. Farming practices can change soil properties, thereby altering the effectiveness of the soil trace elements present. Soil trace element research in extremely arid regions, aiming at the determining effects of different land uses, has received little attention until now. The Cele Oasis (80°03'24″-82°10'34″E, 35°17'55″-39°30'00″N) located on the southern margin of the Tarim Basin, Xinjiang, China, was selected as a study area. Agriculture is the main land use here; however, management intensities differ across the oasis and as the oasis area has grown. In 2005, four experimental fields were selected, representing typical land use types according to local tillage practices. These were newly cultivated, fertilized land (NEF), a field receiving a normal manure application rate (NMF), a field receiving a high manure application rate (HMF) and a field in the Oasis interior (OIF). A single index (Ei) and integral index (Ec) were calculated to evaluate the effects of these land use types on soil trace element availability over 20cm depths. The relationship between soil organic matter and available trace elements was determined by correlation analysis. Our results showed that: (1) There were statistically significant differences in the amounts of available Fe, Cu, Mn, Zn present in the different land uses at a depth of 0-20 cm. Cultivation management can improve the accumulation of soil organic matter and soil particle size distribution, which in turn can increase the availability of soil trace elements to pasture and crops. The application of manure and fertilizer being the main source of available trace elements in these soils was the probable reason for the differences. (2) The farmland (OIF) situated in the oasis interior showed the highest level of trace element availability of all the fields. The main reason for this result would likely be that long-term irrigation has played an important role in altering the availability of soil trace elements, while more than one hundred years’ of careful cultivation management had led to the soil becoming more fertile. (3) A comparison of the unfertilized treatments (i.e. NEF, situated in the edge of the oasis and CTP) showed that the lowest concentrations of available Fe, Cu, Zn, were found in the NEF treatment, which was probably due to the removal of these micronutrients from the soil through crop uptake and harvest. (4) Fertilization of the NMF and the HMF fields (which are also situated in the desert-oasis ecotone) resulted in a positive effect on soil trace element concentrations; the available indices of Fe, Cu, Mn and Zn in the HMF were higher than in the NMF, because of the higher input of manure (see earlier). (5) The results of a correlation analysis indicated that soil organic matter was highly positively correlated with the availability of the soil trace elements, the soil organic matter exerting a significant and direct effect on the availability of Zn, Mn, Fe and Cu in the process of oasis growth. These results indicate that refining agricultural management practices in the process of oasis growth could be beneficial. 参考文献 相似文献 引证文献