多寄主林垂直层次菱形栽种模式的防风固沙响应及灌溉制度研究

Shrub of h. ammodendron windbreak and sand-fixation, ecological restoration, h. ammodendron trees in recent years, h. ammodendron parasitism in the host, big non-success is to increase income, improve the ecological and control the development trend of the desert. H. ammodendron tree planting density and irrigation water is unreasonable, the survival rate of h. ammodendron decreases, resulting in a decline in the production of the parasite, due to the wind tree of h. ammodendron planted rows planting distance affect its illumination time, survival rate, windbreak and sand-fixation effect. For free access to the forest, gradually reduce the wind speed, wind gradually hold the migration of particles of different height, every tree to study and put forward the main h. ammodendron in place are independent of each other, each other is not diamond plant form of keep out sunshine, at the same time, the diamond wind invade the edge density of planting different intercropping vice, diamond internal rules of the host plant host etc. Simulated experiments, all kinds of the experimental results were analyzed to host more forest vertical diamond level plant model. The project to field experiment research, the model and simulation experiment and field experiment of contrast optimization effect of windbreak and sand-fixation plant mode, in this mode to establish the forecast model of wind velocity attenuation and sand-fixation rate. According to the law of changes in soil moisture and climate, we determine the mode of comprehensive irrigation under different irrigation water quota, correct quantitative water saving effect, and degree of control the spread of desertification. For improving the windbreak and sand-fixation, restoration ecology, provided in accordance with the economic and social benefits。

梭梭是防风固沙、生态修复的灌木，最近栽种梭梭树，梭梭以寄主寄生大芸是提高收入、改善生态及控制沙漠的发展趋势。梭梭树栽种密度和灌水量不合理，梭梭的成活率降低，导致寄生物的产量下降，由于防风梭梭林的栽种行株距影响它的光照率、成活率、防风及固沙效果。为风自由进入林中、逐渐降低风速、逐步固住不同高度的运移颗粒，研究提出每棵主寄主梭梭在位置上相互独立、互不遮挡阳光的菱形栽种形式，同时菱形风侵入边栽种不同密度副寄主、菱形内部无规则栽种间作寄主等方面进行了模拟实验，各实验结果进行分析采取多寄主林垂直层次菱形栽种模式。本项目对该模式进行野外试验研究，同时模拟试验与野外试验的防风固沙效果进行对比优选栽种模式，在该模式下建立风速衰减过程与固沙率的预测模型。根据土壤水分及气候的变化规律，不同灌水量下确定该模式的灌水定额，正确量化节水效应及控制沙漠化的蔓延程度。为提高防风固沙、修复生态、经济和社会效益提供依据。

随着区域人口的增多、新开垦面积扩大、各部门用水矛盾日益凸现，缺水现象严重，农业用水挤占环境用水，土地沙漠化。在这种背景下，综合考虑水资源的承载能力、防风林株行距、每亩栽种树的个数，耐旱植物与免灌植物的搭配栽种能减少水量、水土资源的含盐量对植物的影响，降低风灾损失等问题。本项目采用防风固沙林与封沙育草相结合的方法，解决降低风速、削弱风沙流强度等有重大意义的科技问题。选定了需灌溉的耐旱植物梭梭、红枸杞、黑枸杞，免灌植物白蒿和小蓬。结果是：按耐旱性大小排位：梭梭＞白蒿=小蓬≥黑枸杞＞红枸杞；按耐盐性大小排位：梭梭≥白蒿＞小蓬≥黑枸杞＞红枸杞。.1）因为自然菱形生长的梭梭固沙效果好，所以从梭梭的菱形生长着手，根据自然菱形生长的梭梭的规律和固沙过程，确定梭梭的菱形栽种模式及株行距。并在菱形各顶点栽种1棵梭梭树的条件下，菱形的风侵入边不同密度栽种副林（红枸杞和黑枸杞）、菱形内部搭配栽种间作林（免灌植物白蒿和小蓬）等8种模拟试验进行比较，选定了G、E、C三种田间试验模式。结果是：菱形生长的梭梭与模拟试验结果一致，正确反映自然生长的梭梭的规律和固沙效果。.2）室内外土壤水盐运移结果分析可知：相同的滴水下田间土壤水盐随水垂直方向运移距离大于室内试验的。肉苁蓉接种梭梭等寄主物的根部，接种肉苁蓉的最佳位置是离滴头50cm处。草苁蓉只能接种于红枸杞、黑枸杞、白蒿和小蓬寄主物的根部。.3）输沙量的多少与植被覆盖率、植被高度、地面的粗糙度、沙粒的供量和粒径、风纪等都有密切的关系。气流搬运沙量的90%在离地30cm以下运移，植被覆盖率增大，输沙量降低，灌水植物数量多灌水量大。因此，不同植物的灌水定额及需水量确定了灌水定额范围。根据田间试验的结果优选南北疆合理G和C方案。用三条样值插值函数描述风沙颗粒的堆积过程线，弥补观测点间的缺值，绘制风沙颗粒的堆积过程线，并提出堆沙颗粒体积的计算方法。