模拟降雨条件下退化草原不同植被配置产流产沙特性研究

发布时间：2018-06-27 01:40

本文选题：模拟降雨 + 植被配置　；参考：《内蒙古农业大学》2015年硕士论文

【摘要】：植被是影响土壤侵蚀的重要因素,了解锡林郭勒草原植被影响产流产沙情况,是研究该区植被水土保持效益的重要内容。本文以蒙古冰草(Agropyron mongolicum)、无芒雀麦(Bromus ineris)、草木樨(Melilotus suaveolens)、紫花苜蓿(Medicago sativa)为主要研究对象,开展野外人工模拟降雨试验,研究不同雨强、植被结合方式及保水剂施用量下坡面产流产沙特征的变化,主要结论如下：(1)植被与不同保水剂施用量结合时,随着保水剂施用量的增加初始产流时间随之延后,径流延迟时间随之增加。当降雨强度为0.73mm/min时,天然草地施用0g/m2保水剂小区初始产流时间为7.4min,施用50g/m2为15min同一保水剂施用量对植被初始产流和径流延迟时间的影响,表现为相同保水剂施用量下人工草地初始产流时间晚于天然草地,当降雨强度为1.03mm/min时施用50g/m2保水剂,无芒雀麦与草木樨的小区初始产流时间最晚为5.73min比天然草地的2.57min晚3.16mmin。相同雨强,同一保水剂施用量下径流延迟时间差别不大,在0.5min内。(2)不同植被配置施用保水剂后,随着保水剂施用量增加产流量均随之减小。当降雨强度为1.03mm/min时,蒙古冰草与草木樨组合在施用0g/m2保水剂时其产流量为27.82L比施用50g/m2保水剂时多15.02L；同一保水剂施用量对植被产流的影响,表现为产流量和产流时间之间的线性相关关系显著(R20.85),同一保水剂施用量下模拟趋势线进行对比,发现天然草地曲线斜率大于人工草地。(3)不同植被配置施用保水剂后,其地表产沙量受保水剂施用量影响较大,产沙量随着保水剂施用量的增加而减少,产沙量和产沙时间之间的线性相关关系很显著(R20.9),随着降雨强度增加,对不同保水剂施用量下模拟趋势线进行对比,发现曲线斜率随保水剂施用量的增加而明显的减小；同一保水剂施用量对植被产沙的影响,表现为相同保水剂施用量下,蒙古冰草与草木樨的组合更适合当地防治水土流失工作。当降雨强度为1.03mm/min时,蒙古冰草与草木樨组合在施用50g/m2保水剂时产沙量是737.15g为天然草地1180.53g的62%。
[Abstract]:Vegetation is an important factor affecting soil erosion. It is an important content to study the benefit of vegetation soil and water conservation to understand the effect of vegetation on runoff and sediment production in Xilinguole grassland. In this paper, the main research object was (Agropyron mongolicum), ineris), suaveolens), alfalfa (Medicago sativa), and the field simulated rainfall experiment was carried out to study the different rainfall intensity. The main conclusions are as follows: (1) when the vegetation is combined with different water retaining agents, the initial runoff production time is delayed with the increase of the amount of water retaining agent. The delay time of runoff increases. When the rainfall intensity was 0.73mm/min, the initial runoff production time was 7.4 min when the natural grassland was treated with 0g/m2 water retaining agent, and the effect of the application of the same water retaining agent 50g/m2 on the initial runoff yield and runoff delay time of the vegetation was studied. The results showed that the initial runoff production time of artificial grassland was later than that of natural grassland under the same water retaining agent application rate. When the rainfall intensity was 1.03mm/min, the initial runoff time of the plot without bromegrass and sweet clover was 3.16 mmin. later than that of the natural grassland when the rainfall intensity was 1.03mm/min. Under the same rainfall intensity, the delay time of runoff under the same water retaining agent was not different, and in 0.5min. (2) with the increase of the amount of water retaining agent, the yield and flow rate decreased with the application of water absorbent in different vegetation. When the rainfall intensity was 1.03mm/min, the yield and flow rate of the combination of Mongolian ice grass and sweet clover were 27.82 L and 15.02 L higher than that of the application of 50g/m2 water absorbent, and the effect of the same water retaining agent on vegetation yield and runoff was observed. The linear correlation between runoff and runoff time was significant (R20.85), and the curve slope of natural grassland was higher than that of artificial grassland, compared with the simulated trend line under the same dosage of water retaining agent. (3) after different vegetation was applied with water-retaining agent, the slope of curve of natural grassland was higher than that of artificial grassland. The surface sediment yield is greatly affected by the amount of water retaining agent, and the sediment yield decreases with the increase of the amount of water retaining agent. The linear correlation between sediment yield and sediment yield time is significant (R20.9), and with the increase of rainfall intensity, the amount of sediment yield decreases with the increase of the amount of water retaining agent, and the correlation between sediment yield and sediment yield time is significant (R20.9). By comparing the simulated trend lines under different water retaining agents, it is found that the slope of the curve decreases obviously with the increase of the amount of water retaining agent, and the effect of the same amount of water retaining agent on the sediment yield of vegetation is shown as the same amount of water retaining agent. The combination of Mongolian ice grass and sweet clover is more suitable for soil erosion control. When the rainfall intensity was 1.03mm/min, the sediment yield of the combination of Mongolian ice grass and sweet clover was 737.15g and 1180.53g when 50g/m2 water-retaining agent was applied.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S812

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