【作者】 孟广涛；

【导师】 贺康宁；

【作者基本信息】 北京林业大学 ， 生态环境工程， 2008， 博士

【摘要】 金沙江流域是长江流域典型的生态脆弱区。流域森林的生态功能,水源涵养功能剧减,水土流失严重。该区退化森林生态系统的恢复与重建技术研究对长江流域的生态安全及社会、经济可持续发展具有重要的意义。本研究以国家天保工程县—永仁县为主要试验区,从2004年至2007年,以“近自然林”思想为指导,从森林生态系统的角度出发,系统分析了不同退化森林生态系统类型的主要干扰因素,退化天然林生境和群落变异的时空异质性,退化天然林的分类原则、退化等级确定标准和分类系统,退化天然林封育恢复技术体系及评价标准;通过实验生态学手段,对退化阶段天然次生林的结构调整快速恢复技术,天然林区严重退化生境生态重建技术,天然林区大面积人工纯林改造技术,不同类型退化生态系统的恢复重建模式及不同模式的生态功能进行了分析研究,评价选择出适应不同退化林分类型的恢复重建模式并提供相应的配套技术,研究结果如下:(1)按景观生态系统的结构和功能,将金沙江流域天然林生态系统划分为3个森林生态区和10个森林生态亚区。按干扰等级,流域退化天然林分为微度退化类型、轻度退化类型、中度退化类型和重度退化4个类型。(2)云南金沙江流域退化森林适宜的恢复模式有封禁、封调、封造和封改4种模式,其配套恢复技术组成了完整的森林恢复技术体系,形成乔林、乔灌、乔灌草、灌林和灌草5个恢复培育类型。(3)通过封禁恢复,退化天然林的物种多样性、生产力明显提高,土壤理化性质改良显著,天然林水源涵养能力大幅提高。(4)封调措施成效:通过封调,林分质量得到提高,群落结构多样化,群落物种多样性增加,生态功能加强。(5)封改对人工林的恢复效果良好。通过封改的云南松人工林能在短时间内形成混交复层结构,物种多样性显著提高,林分的保土、保土能力增强。(6)对旱冬瓜、圆柏、藏柏、柳杉、川滇桤木、云南松人工林和旱冬瓜×云南松、旱冬瓜×园柏、云南松×圣诞树、藏柏×旱冬瓜混交人工林的研究表明,封造能使立地条件得以恢复,土壤肥力回升,蓄水功能加强。在中山区,造林4年后,土壤的结构得到了明显改善,土壤肥力和保水保肥能力有不同程度的提高。在干热河谷,以麻栎、锥连栎和槲栎恢复起来的植被较为稳定。(7)本研究提出了云南金沙江流域退化天然林结构调整快速恢复技术规程草案,疏林地、低效林地、灌木林地、中幼林地和退化荒草地可进行封抚、封补、封调、封改和封保等措施措施。云南金沙江流域人工纯林近自然化改造技术规程草案以是分布在亚热带湿润和半湿润气候带内,生长不良、树种单一的人工林分为恢复对象,进行封调改造、封育造林、皆伐改造和复壮抚育。更多还原

【Abstract】 Jinsha River drainage area is one part of Yangtze River drainage area, and it has an typical fragile ecological environment. Ecological function and water conservation function of the forest in this area declined sharply, which lead to serious water and soil erosion. Study on the technology of resuming and rebuilding of the declining forest ecosystem has an significant meaning to the eco-security and sustainable development of Yangtze River drainage area.The research takes Yongren County (NFPP County) as main sites of the experiment. The idea of‘Close to Nature Forest’is introduced for the research from the perspective forest ecological system. The research gives an systematic analysis on disturbance factors of different degraded forest ecological system ,including the heterogeneity in regional spatio-temporal scale of degraded natural forest habitat and community variation, category principles of degraded natural forest, grading criteria and categorizing system for degrading level, restoration system and evaluation criteria for the closure and conservation of degraded natural forest; Based on the experiment to carry out research on adapting the structure of the secondary natural forest at degraded stage for exploration of proper approaches for a rapid restoration, rehabilitation technology for heavy degraded forest, technology for improvement of large area of mono plantation in the natural forest area, restoration models for different degraded ecological system and ecological functions of different models. Feasible models for restoration and rehabilitation with corresponding techniques are selected for different degraded forest. Main research results are as follows:(1)It can be divided into 3 zones then 10 sub-zones of the natural forest eco-system in Jinsha River drainage area based on the structure and functions of its landscape system, and 4 categories based on its position in natural succession: slight degraded, small degraded, mid-level degraded and heavy degraded.(2)There are 4 feasible models for closure and conservation have been developed (strictly hillside closing, closing and forest structure adjustment, closing and afforestation and closing and forest stand improvement) for the upper of Jinsha River. Integrated together with corresponding technology, it makes an whole technological system for the restoration of the forest and 5 models for restoration and cultivation: tree forest, tree shrub, tree shrub and herbage, shrubs and herbage.(3)In the model of strictly hillside closing, all of species diversity, biologic productivity, physical-chemical properties of soil, water conservation capacity of the forest got an remarkable improvement.(4)In the model of hillside closing and forest stand structure adjustment, Quality of forest stand improved. Community structure got diversification. Community species diversity increased. Ecological function strengthened.(5)In the model of hillside closing and forest stand improvement, it takes a relatively short time for Pinus plantation forest stand in community structure changing from mono into mixture forest. Species diversity increased remarkably and capacity for water and soil conservation strengthened.(6)Study on afforestation of Alnus nepalensis, Sabina recarva, Cupressus torulosa, Cryptomeria fortunei, Alnus ferdinandi-coburgii, Pinus yunnanensis, Alnus nepalensis×Pinus yunnanensis, Alnus nepalensis×Sabina recarva, Pinus yunnanensis×Acacia dealbata and Cupressus torulosa×Alnus nepalensis in the model of hillside closing and afforestation shows: this model made soil fertility and water holding capacity improved, site condition is getting better. Soil structure improved greatly, fertility and water holding capacity improved after 4 years of afforestation. In Dry and hot valley, the restored vegetation with Quercus acutissima,Quercus franchetii,Quercus aliena is very stable.(7)Two drafts of technical rules were proposed based on the research. One is for rapid restoration and forest structure adjustment in Jinsha River drainage area of Yunnan and the other is improvement technical rules for mono plantation to close natural forest. The first one aims at open forest land, low yield forest land, shrub land, mid age young forest land and degraded grassland, and it puts forward five methods: closing with tending type, closing with replanting type, closing with adjustment, closing with improvement and closing with conservation (protection); The second one aims at mono plantation distributed in subtropical humid and semi-humid area, and it puts forward four methods: closing with adjustment, closing with tree planting, selective cutting with improvement and tending with improvement.更多还原