黄花草木樨改良盐碱土的试验研究

在调查陕北地区不同地域作物(谷子)、人工草灌(苜蓿与柠条)和天然草地(退耕地)的生产力,土壤水分及耕层养分的基础上,对比研究了不同类型植物生产力的差异,并分析了引起差异的原因及限制生产力提高的因素。结果表明,作物地(谷子)生产力占据明显优势,但稳定性较差;人工草灌(苜蓿与柠条)及天然草地的生产力较谷子低;天然草地群落的生产力、稳定性、物种丰度指数和土壤养分含量均较优越。指出除水分不足是限制不同植物生产力发挥的主要因素外,土壤养分含量低和缺乏管理也是限制植物生产力提高的重要因素。同时指出,为达到正确评价不同类型植物的生产力和长期适应性,为该地区大范围植被建设提供依据和参考,应设立定位或半定位研究点进行长期测定与研究。

Improving Effect of Melilotus Offcinalia on Saline-alkaline Soil

Based on an investigation into productivity, soil water and soil nutrient content of croplands, artificial grasslands (Medicago saliva) and shrub forests (Caragana korshinskii), and natural grasslands in the northern region of Shaanxi Province, the productivity differences among different vegetation types and territories are discussed comparatively, and the reasons for these differences are analyzed. The results show that the productivity of croplands( foxtail millet) was far better than that other plants or vegetation types, but production stability is relatively poor in these systems. Productivity in artificial grasslands, shrub forests and natural grasslands is lower than in croplands, productivition stability, community biodiversity index and soil nutrient content of natural grasslands are the best among the surveyed plants (or vegetation types). It is proposed that besides water, low soil nutrient content and short of reasonable running also limit plant productivity improvement. To evaluate the productivity and longterm adaptation of different plants to the environment and offer guidance to the construction of vegetation systems in the region, long-term research areas or provisional survey study spots should be founded.