Study On Ecology Water Requirement And Planting Technique Of Zanthoxylum Bungeanum Var. Dintanensis Forestland In Karst Area

Based on the theory of soil-plant-atmosphere continue water balanced, Zanthoxylum bungeanum var. dintanensis in Karst area was studied in the paper. Through studying physical characters of soil in Karst area ,micro-climate atmosphere, soil moisture content changing law under nature condition,vapour content of trees,ecological requiring water content of forest land, ecological shortage content of forest land, and examination on survival rate of seedling,this paper. Then gave a series of technical measures.The result shows that: Karst environment's high heterogeneity, microhabitat and micro-climate are very different. During a day, the water in soil increases with the soil thick incleased, bur stables finally. The water condition of stony golly is best, but the water condition of soil surface and stony trough are worse .The water condition of stony trough is worse than soil surface. Stony trough moisture content's shortage is the most serious, then is the soil surface. Under the litter leaf cover, stone cover and film cover, the day change range is stony trough>stony gully>soil surface, stony gully>soil surfacostony trough,stony gully >soil surface>stony trough .Continue to dry for seven days, soil moisture content begins to stress .But during a year, average water content of soil and year change range shows: stony gully> stony trough>soil surface. Changing in water that included in different microhabitat soil exists, and the time ranges are not very same. The water stress in microhabitat occurs with high -frequency. The course of soil expended water under controlling shows that soil moisture content constantly reduced under the condition of higher temperature and lower moisture, the tend is quick first and slow last , but stables finally. Soil moisture content's expenditure is related with cover material, cover degree and soil volume. Film cover is better than stone cover, litter leaf cover in maintaining water is worse. After examining the result of survival rate, it shows that survival rate of stone cover is highest, then is the litter leaf cover, and the film cover is worstZanthoxylum bungeanum var. dintanensis's water expenditure in expanding leaf-period (3-4m), blossom and fluitness-period (5-6m),and mature-time (7-8m) is respectiviely 17.66mm, 109.1mm, 44.03mm.Total water expenditure in growth-period is 170.70mm. To different micro-hibitat (soil surface,stony trough, stony gully), the soil water vapour content in expanding leaf-time (3-4m) is respectively 62.18mm, 65.31mm, 66.45mm, which is in blossom and fluitness-period is respectively 101.95mm,104.3mm,93.56mm; and which is in mature-period is respectively 182.47mm, 150.54mm, 174.28mm.In experimental region, there are three microhabitats of soil surface, stony pit and stony gully.Range of potentical ecological water repuirement of forestland in the growth of every 100 m~2 are 13.996—21.032m~3, 3.916—5.462m~3, 3.726—5.296m~3 respectively, with a range of total ecological water repuirement is 21.638m~3—31.790m~3.However reality ecological water repuirement of soil surface, stony pit and stony gully are 16.135m~3,3.584m~3, 4.298m~3 respectively, which of total ecological water repuirement is 24.018m~3.Total ecological water shortage in the...