摘要
黄土高原丘陵沟壑区林草植被建设对控制水土流失和农业可持续发展具有双重意义。但是,大量资 料表明,黄土高原丘陵沟壑区林地和草地土壤水分严重亏缺,林草植被对土壤水资源的过度利用必将产生严 重后果,笔者强调生态植被建设须坚持土壤水资源平衡利用原则。在对土壤水量收入和支出诸因素分析的基 础上,指出采取拦蓄降水、降水高效叠加利用、覆盖保墒和减少植被蒸腾等途径及措施,以实现土壤水资源平 衡利用。提出林地降水高效叠加利用技术的思路及研究解决办法;研究建立植物蒸腾耗水量评价指标体系, 为筛选节水植物种类或种提供科学依据;植被蒸腾量的调控,根据叶面积指数与土壤耗水量的关系,在土壤水 资源平衡利用的原则下,确定其盖度和种植密度,后期通过控制树冠、适度疏枝、合理平茬(刈割)等进一步加 以调节。
Construction of forest and grass vegetation has dual significances to control of soil losses and sustainable development of agriculture in hilly areas of the loess plateau. However, a large number of data and materials show that forestland and grassland are in great deficit of soil moisture, and overuse of soil water resource by forests and grasses must result in some serious sequent. The writers stress that construction of ecological vegetation must persist in the principle of balanced use of soil water resource. Based on the analyses of main factors affecting input and output of soil moisture, the writers indicate that balanced use of soil water resource can be realized by ways of intercepting and storing up rainfall, efficient and folded using rainfall, mulching, decreasing transpiration and so on. And the writers put forward some clues and designed methods on efficient and folded use of rainfall for forestlands; setting up evaluation index system of water losses by plant transpiration, in order to provide the base for selection of water-saved plants with less evaporation; to regulate transpiration of vegetation, its cove degree and planting density are decided in principle of balanced use of soil water resource based on the relation of leaf area index and soil water deplete, and in later growing period its transpiration can be further adjusted by controlling crown of trees, moderate disbranching and rational cutting.
出处
《西北农业学报》
CAS
CSCD
北大核心
2005年第4期92-96,共5页
Acta Agriculturae Boreali-occidentalis Sinica
