水土保持措施下坡面土壤养分变化特征研究

发布时间：2018-04-26 21:27

本文选题：坡地 + 水土保持措施　；参考：《沈阳农业大学》2017年硕士论文

【摘要】：由于东北坡地被大量的垦殖,但没有实施行之有效的土壤退化防治措施,从而导致水土流失,大量的泥沙以及氮、磷、农药等面源污染物汇入受纳水体,造成其水质恶化、富营养化等环境问题。因此,应积极探索控制面源污染的水土流失治理技术,减缓面源污染,保障区域水质安全。本文以桓仁满族自治县大泉眼小流域典型试验区水土保持措施体系和在沈阳农业大学水利学院综合实验基地内种植的不同宽度植物篱为研究对象。利用GPS定点采样,采用传统统计分析方法和ArcGIS地统计方法相结合,选取最优拟合模型(球状模型),采用克里格(Kriging)法进行最优空间插值方法,绘制各种土壤特性含量的空间分布图,从而分析研究水保林地、水平梯田、地埂植物带和无措施对照区土壤养分的时空变化特征。同时,为了更好地建设耗资少、工程量小、见效快的植物篱,本研究在试验区通过栽培不同宽度的植物篱,设置不同采样点以及分层取样,从而研究植物篱对较短坡长坡面土壤肥力的影响。得出的结论如下:(1)研究区内有机质、全氮、全磷和有效磷含量均随着土层深度的增加而降低。4个指标的空间变异度对比:全磷有效磷全氮有机质,其全氮、全磷、有效磷的空间变异受水土保持措施影响显著,而有机质不仅受水土保持措施影响,还受人为因素影响。运用Kriging插值制图显示,4个指标在空间上均分布不均匀。采取水土保持措施后对土壤养分有一定的富集作用,含量显著高于无措施对照区,且水土保持措施能使坡耕地土壤养分在垂直方向上相对均匀分布;无措施坡耕地坡上、坡中和坡下部位土壤养分呈规律性斑块分布。上坡位的水保林地对全氮、全磷和有机质的拦蓄作用最好,中坡位的水平梯田对有效磷的拦蓄作用显著;由于下坡位的无措施对照区作为土壤养分流失的必经区域,土壤养分含量有所富集,表现出地埂植物带对养分的拦蓄作用不显著。经统计分析表明,水土保持措施区0～15 cm有机质和全氮变异系数大于无措施对照区,但土壤全磷和有效磷变异系数则小于对照区;无措施对照区15～30 cm有机质、全氮、全磷和有效磷变异系数大于水土保持措施区。水土保持措施与不同深度土壤养分之间均呈极显著正相关关系,0～15 cm与15～30 cm两层土壤全氮和有效磷之间均呈显著正相关,而0～15 cm与15～30 cm两层土壤其他各指标关系间均呈极显著正相关关系。不同深度有机质、全氮、全磷和有效磷含量均随月份变化先增加后损失,但其变化程度因水土保持措施不同而不同。(2)植物篱宽度与坡面有机质、有效磷之间存在一定的相关性,在上坡位布设较宽植物篱能更好地使土壤有效磷在坡面上均匀分布。0～15 cm有机质和有效磷变化受植物篱的影响较大,15～30 cm有机质和有效磷变化幅度较小。植物篱可以改变坡面微地形,0～15 cm有机质和有效磷在带上部位富集,含量最高,而15～30 cm层在带中含量最高。有机质在坡面呈高度耗损,而有效磷呈高度富积。因此,种植草本植物篱时,应该考虑合适宽度,选择适时适地的植物种,考虑植物篱给带下和带间部位带来的养分流失,加强植物篱带下和带间土壤的管护,从而提高整体土地生产力。
[Abstract]:Due to a large amount of reclamation in the northeast slope land, the effective measures for soil degradation have not been implemented, which leads to soil erosion, a large amount of sediment and nitrogen, phosphorus, pesticide and other non-point sources of pollutants into the receiving water, resulting in environmental problems such as water quality deterioration, eutrophication and other environmental problems. Therefore, it is necessary to actively explore the treatment of soil and water loss in the control of non-point source pollution. In this paper, the soil and water conservation measures system in the typical experimental area of Daquan small watershed in Huanren Manchu Autonomous County and the different width hedgerows planted in the comprehensive experimental base of the Water Conservancy Institute of Shenyang Agricultural Uinversity are studied in this paper. The traditional statistical analysis method and the traditional statistical analysis method are used in this paper. The ArcGIS land statistical method is combined to select the optimal fitting model (spherical model) and use the Craig (Kriging) method to carry out the optimal spatial interpolation method. The spatial distribution maps of various soil characteristics are drawn to analyze and study the temporal and spatial variation characteristics of soil nutrients in the water conservation forestland, the horizontal terrace, the ridge plant belt and the uncontrolled area. In order to better build the plant hedgerow with small cost, small project and quick effect, this study studies the effects of different sampling points and stratified sampling on the different width of Hedgerows in the experimental area, and studies the effects of Hedgerows on the soil fertility of the short slope and long slope surface. The conclusions are as follows: (1) the organic matter, total nitrogen, total phosphorus and efficiency in the study area are as follows. The phosphorus content decreased with the increase of soil depth and reduced the spatial variation contrast of.4 index: total phosphorus effective phosphorus total nitrogen organic matter. The spatial variation of total nitrogen, total phosphorus and effective phosphorus was significantly affected by soil and water conservation measures, while organic matter was affected by soil and water conservation measures, but also influenced by human factors. The use of Kriging interpolation and mapping showed that 4 The index of soil and water conservation measures has a certain enrichment effect on soil nutrients, and the content of soil nutrients is significantly higher than that in the non measure control area, and the soil and water conservation measures can make the soil nutrient in the sloping farmland relatively evenly distributed in the vertical direction; the soil nutrients in the slope and the lower slope of the sloping slope farmland are regularly speckled. The water conservation area of the upper slope is the best for total nitrogen, total phosphorus and organic matter, and the horizontal terrace in the middle slope has a significant effect on the accumulation of effective phosphorus. As the non measure control area of the lower slope position is a required area for soil nutrient loss, the soil nutrient content is rich, showing the effect of soil ridge plant belt on nutrient retention. The statistical analysis showed that the variation coefficient of organic matter and total nitrogen of 0~15 cm in soil and water conservation measures was greater than that in the control area, but the variation coefficient of total phosphorus and available P in soil was less than that in the control area; the variation coefficient of total nitrogen, total nitrogen, total phosphorus and available phosphorus was greater than that of soil and water conservation measures in the non measure control area. The measures of soil and water conservation and soil conservation were more than that of the control area. There was a very significant positive correlation between soil nutrients at different depths. There was a significant positive correlation between 0~15 cm and 15~30 cm two layers of soil total nitrogen and available P, while 0~15 cm and other indexes of 15~30 cm and two layers had a very significant positive correlation. The change first increased after the loss, but the degree of change was different because of the different soil and water conservation measures. (2) there was a certain correlation between the width of hedgerow and the organic matter and effective phosphorus on the slope. The layout of the wide plant hedgerow in the upper slope could make the soil available phosphorus evenly distributed.0 to 15 cm on the slope surface, and the change of organic matter and effective phosphorus was influenced by the shadow of hedgerow. 15~30 cm organic matter and effective phosphorus change slightly. The hedgerow can change the slope surface microtopography. The 0~15 cm organic matter and effective phosphorus are enriched in the belt and the content is the highest. The 15~30 cm layer is the highest in the belt. In order to improve the overall productivity of land, we should consider the appropriate width, select the suitable plant species in time, consider the nutrient loss caused by the hedgerow, and strengthen the control of the soil under the hedgerow and the interband.

【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S157;S158

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