全膜双垄沟播技术改良荒漠化退化草原的研究

[目的]探讨全膜双垄沟播技术改良荒漠化退化草原的效果,以期为扩大该技术的应用领域提供理论依据和技术贮备。[方法]在宁夏盐池荒漠化退化草原中采用常规方法补播丛生禾本科牧草,并对其进行起垄覆黑膜、起垄覆透明膜、起垄不覆膜和不起垄不覆膜平播的4种保育处理,通过分析各处理的土壤含水率变化规律及其对补播苗生长的影响,寻找最优处理方式。[结果]从7月到11月起垄覆黑膜、起垄覆透明膜、起垄不覆膜和平播4个处理的土壤平均含水率分别为9.88%、9.24%、8.75%和8.13%,各处理间差异显著;补播牧草的成活率分别是96.2%、93.4%、45.6%和28.3%,覆膜相对不覆膜成活率达到极显著水平。其中以覆黑膜具有较大优势,其垄顶土壤含水率有"削峰填谷"的缓冲作用,覆黑膜土壤水分含量比平种提高了21.5%,且对于1 m以下土壤的水分补充量也是最大的。覆膜虽然增加了费用,但从总体效益分析,利润高于不覆膜。[结论]该研究为起垄覆黑膜技术在荒漠化退化的草原补播改良中的推广应用奠定了试验基础。

Effect of Planting in Furrow and Whole Plastic-film Mulching on Double Ridges on Improving Degraded Desert Grassland

[Objective] This study aimed to provide theoretical basis and technologies for the application of planting in furrow and whole plastic-film mulching on double ridges.[Method] The conventional method was used to re-seed the bunch Gramineous forage in the degraded desert grassland in Yanchi,Ningxia Hui Autonomous Region.Four kinds of conservation treatments,namely,ridging with black film mulching,ridging with transparent film mulching,ridging with no mulching and the flatplanting with no ridging and mulching were conducted to the forage to analyze the effects of each treatment on soil moisture and seedling growth.[Result] From July to November,the moisture contents of ridging with black film mulching,ridging with transparent film mulching,ridging with no mulching and the flatplanting were 9.88%,9.24%,8.75% and 8.13%,showing significant differences among the treatments;the survival rates of re-seeding forage were 96.2%,93.4%,45.6% and 28.3%,and the mulching treatment showed significant difference with the un-mulching treatments in survival rate.The treatment with black film mulching showed great advantage that its moisture content on ridge top had the buffering effect of "load shifting",and the soil moisture content of black mulching treatment increased 21.5% than the flatplanting.Black film mulching also had the largest water supplement amount in soil below 1 m.Although mulching cost too much,its overall benefits were higher than that with no mulching.[Conclusion] This study lays the experimental basis for the application of planting in furrow and whole plastic-film mulching on double ridges in improving degraded grassland desertification.