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41.
为探究紫色土坡地植物篱篱前淤积带与篱下土坎土壤抗蚀性的差异及变化规律,选取遂宁市水土保持试验站10°新银合欢植物篱小区(T1)、10°和15°香根草植物篱小区(T2和T3)进行研究。研究小区布设有上、中、下坡篱带,分别采集篱前淤积带和篱下土坎(下坡无)的表土样,测定有机质含量、水稳性团聚体和微团聚体组成,运用主成分分析法对土壤抗蚀性进行分析。结果表明:同一篱带,土壤有机质含量、团聚度和团聚状况均是篱前淤积带高于篱下土坎,土壤水稳性团聚体含量和抗蚀性综合指数则反之,篱下土坎的抗蚀性综合指数是篱前淤积带的1.48～3.17倍;同一小区,篱前淤积带土壤有机质含量、团聚度和团聚状况均表现为下坡中坡上坡,篱下土坎为中坡上坡,而土壤水稳定性和抗蚀性综合指数在坡位间则无显著性差异;同坡度下,香根草植物篱小区土壤有机质含量、团聚度、团聚状况和水稳定性均高于新银合欢植物篱小区;坡度越大,香根草植物篱小区土壤有机质含量、团聚状况和水稳定性表现越差;主成分分析发现,水稳性团聚类指标能较好地反映紫色土坡地土壤抗蚀性能的强弱,研究小区土壤抗蚀能力表现为T2T1T3。 相似文献
42.
基于遂宁水土保持试验站坡耕地2012—2016年次降雨和径流输沙数据,定量分析了自然降雨下植物篱对坡耕地产流产沙及微地形的影响。结果表明:植物篱小区总径流深是对照小区的80%~84%,总冲刷量是对照小区的34%~44%,植物篱减沙作用优于减流。对照小区(Ⅱ小区和Ⅴ小区)径流深、冲刷量与平均雨强、降雨量均极显著相关(P0.01);植物篱小区(Ⅰ小区、Ⅲ小区和Ⅳ小区)径流深、冲刷量与平均雨强、降雨量均呈正相关,其中径流深与降雨量极显著相关。各雨型间产流产沙差异不显著,其中植物篱对A型雨(大雨强、短历时)减流减沙效果优于B型雨(中雨强、中历时)和C型雨(小雨强、长历时)。定植植物篱后,篱带前出现泥沙淤积带,15°香根草(Ⅰ小区)、10°香根草(Ⅲ小区)和10°新银合欢(Ⅳ小区)平均坡度分别演变为11.97°,7.73°和7.89°,香根草植物篱的效果较明显,植物篱使得坡耕地梯田化发展。 相似文献
43.
The relation between two species of bats, the pipistrelle (Pipistrellus pipistrellus (Schreber, 1774)) and the serotine (Eptesicus serotinus (Schreber, 1774)) and linear landscape elements such as hedgerows, tree lines and tree lanes was studied in an agricultural
area in The Netherlands. The pipistrelle was observed almost entirely close to landscape elements, while serotines more frequently
crossed fields and meadows. Serotine activity in these open areas was, however, negatively related to the distance to a landscape
element and to windspeed.
On a landscape scale the results indicate a more than proportional positive relation between the density of serotine bats
and the density of linear landscape elements, whereas this relation was only proportional in the case of the pipistrelle.
It is argued, that landscapes with a high density of linear elements have a surplus value for serotine bats.
Three possible functions of linear elements for bats (orientation clues, foraging habitat and shelter from wind and/or predators)
are discussed. Any of these may explain the results of this study. 相似文献
44.
为减少坡耕地水土流失现状,提高种植经济收入,在秭归县九畹溪镇实施5种农林复合种植优化模式.以农作物作为对照,对这5种模式生长情况进行调查,同时对经济效益和生态效益进行评估.结果表明：①主要树种成活率在90％以上,保存率在85％以上,保存面积达100％;②从经济效益上来看,农林复合种植模式总收入远高于单纯农作物种植模式,进入盛产期后以核桃＋茶叶埂模式收入最高,未进入盛产期时以香椿 药材＋茶叶埂模式收入最高;③从生态效益来看,项目的实施每年平均可减少土壤流失532.61 t,年均径流量减少15 998.40 m3,全氮、全磷、有效钾年均流失量分别减少12.89,12.58,2.05 t. 相似文献
45.
Drip fertigation and plant hedgerows significantly reduce nitrogen and phosphorus losses and maintain high fruit yields in intensive orchards 
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下载免费PDF全文 SONG Ke QIN Qin YANG Ye-feng SUN Li-juan SUN Ya-fei ZHENG Xian-qing LÜ Wei-guang XUE Yong 《农业科学学报》2023,22(2):598-610
A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake Basin. Nitrogen and phosphorus runoff over a whole year were measured by using successional runoff water collection devices. The four experimental treatments were conventional fertilization (CK), drip fertigation (DF), conventional fertilization combined with plant hedgerows (C+H), and drip fertigation combined with plant hedgerows (D+H). The results from one year of continuous monitoring showed a significant positive correlation between precipitation and surface runoff discharge. Surface runoff discharge under the treatments without plant hedgerows totaled 15.86% of precipitation, while surface runoff discharge under the treatments with plant hedgerows totaled 12.82% of precipitation. Plant hedgerows reduced the number of runoff events and the amount of surface runoff. Precipitation is the main driving force for the loss of nitrogen and phosphorus in surface runoff, and fertilization is an important factor affecting the losses of nitrogen and phosphorus. In CK, approximately 7.36% of nitrogen and 2.63% of phosphorus from fertilization entered the surface water through runoff. Drip fertigation reduced the accumulation of nitrogen and phosphorus in the surface soil and lowered the runoff loss concentrations of total nitrogen (TN) and total phosphorus (TP). Drip fertigation combined with plant hedgerows significantly reduced the overall TN and TP losses by 45.38 and 36.81%, respectively, in comparison to the CK totals. Drip fertigation increased the vertical migration depth of nitrogen and phosphorus nutrients and reduced the accumulation of nitrogen and phosphorus in the surface soil, which increased the pear yield. The promotion of drip fertigation combined with plant hedgerows will greatly reduce the losses of nitrogen and phosphorus to runoff and maintain the high fruit yields in the intensive orchards of the Tai Lake Basin. 相似文献