景电灌区农田防护林衰败及优化模式

Study on the decline and optimized model of agriculture protective forest ecosystem in the Jingtai electrical irrigation area

景电灌区农田防护林网是景电灌区防护林体系的重要组成部分,通过调查景电灌区农田防护林衰败现状,分析退化原因,提出优化改造模式,为景电灌区农田防护林更新改造从而发挥可持续效益提供技术支撑。结果表明,1)以杨树为主要树种的景电灌区农田防护林网目前呈严重衰败状态,尤其在个人管护的区域,残缺断代现象严重,部分地方甚至基本消失;2)病虫危害,耗水、胁地严重而被砍伐,耕地次生盐渍化导致树木生长不良、枯死,树种单一、结构不合理,管理不到位等是造成农田防护林衰败的主要原因;3)三倍体毛白杨(Populus tomentosa)、廊坊(P.langfanggensis)、樟子松(Pinus sylvestris)、刺槐(Robinia pseucdoacacia)、白蜡(Fraxinus chinensis)、鸣山大枣(Jujube minshan)等树种为该地区农田防护林建设的适宜树种,可采用农田防护林杨树优势树种轮换、针叶常绿树种优化改造、生态经济型防护林网营造等模式对景电灌区农田防护林网进行更新改造。农田防护林网的改造,将对完善防护林体系,保障景泰绿洲的安全产生重要意义。

Agriculture protective forest is an important part of the protective forest system in the Jingtai electrical irrigation area.In order to provide technology support for renewal and reform of agriculture protective forest,the optimized model was proposed according to the analysis of present situation and degradation reasons.The result showed the agriculture protective forest predominated by Populus seriously declined,especially in terms of personal management areas which were incomplete or totally disappeared.The main reasons for these declines included the pests and diseases damage,cutting down because of serious water consumption and soil threat,poor growth and death because of serious farmland secondary salinization,single tree species and unreasonable structure,insufficient management.The renewal and reform of agriculture protective forest was necessary and feasible through employed excellent species,such as Populus tomentosa,P.langfangensis,Pinus sylvestris,Robinia pseucdoacacia,Fraxinus chinensis,Jujube minshan with rotation with dominant species of Populus and optimal modification of evergreen needle tree species.These optimization will have important influences on the improvement of the protective forest ecosystem and guarantee safety of Jintai oasis