【作者】 朱丽；

【导师】 姚云峰；

【作者基本信息】 内蒙古农业大学 ， 水土保持与荒漠化防治， 2010， 博士

【摘要】 华北土石山区生态环境脆弱,水土流失严重,土地沙化加剧,自然灾害频繁,是我国生态建设的重点区域。但由于防护林空间布局与结构配置不尽合理,严重阻碍防护林生态功能的发挥。为优化防护林空间配置,本研究结合“十一五”国家科技支撑“防护林体系空间配置和结构优化技术研究”,在流域尺度上,从适宜森林覆盖率、森林类型比例、空间配置与水源涵养功能的关系着手,对华北土石山区红门川流域防护林空间配置、防护林体系与水土资源的关系进行深入研究,提出了典型流域防护林空间配置模式。本论文以红门川流域1990～2006年水文气象资料为基础,利用四期遥感资料研究各时期流域土地利用景观特征,从景观斑块特征指数、景观异质性指数、景观多样性指数、景观类型转移矩阵等角度对流域土地利用格局的演变特征进行深入分析;利用主成份分析法,对流域景观类型变化的驱动因子进行分析,判定并分析流域土地利用变化的主要驱动力;然后分析流域降水与径流的变化规律,并结合土地利用/森林植被的变化研究防护林的水源涵养功能。在参数率定的基础上,确定了SWAT模型在红门川流域的适用性,并利用该模型模拟降水与森林植被协同变化的产流响应。最后从森林覆盖率、森林类型比例及其空间配置方面设定不同情景模拟平水年下产流,得到流域防护林空间配置的优化方案。主要研究成果如下:(1)1990～2005年期间,红门川流域林地类型虽然发生较大变化,仍然以针叶林和阔叶林为主。景观具有较为明显的破碎化趋势,斑块呈现不规则化趋势。经济加快发展的过程中人为因素对土地利用的影响范围和力度有所加大。(2)红门川流域1990～2006年期间降水量和径流虽有波动,但总体呈现下降趋势,径流减少的幅度远大于降水。径流具有明显阶段性,1990～1998年径流量较大,而后期相对较小,后期植被条件较好的土地利用较前期产流能力有所下降。(3)通过灵敏性分析、模型的自动校准研究SWAT模型在研究区的适用性,得到较好的验证。在此基础上,模拟得到径流对降水与森林植被变化的协同响应,发现森林植被变化对汛期和丰水年产流影响较大。不同森林类型调蓄径流功能不同,其排序为:灌木林<针叶林<混交林<阔叶林。(4)选择地貌、坡度、坡向、土壤厚度、土壤母质五个因子,对红门川流域立地条件进行划分,共分为17种立地类型。以森林覆盖率为基准设定7种情景,根据立地条件进行防护林空间配置。利用SWAT模型模拟不同防护林空间配置下的产流量,结果显示,森林覆盖率70%的情景下,流域产流量小于2004年实测值,防护林涵养水源功能发挥较好,可以认为是合理森林覆盖率。且森林类型比例——阔叶林31.58%,针叶林22.96%,混交林35.53%,灌木林9.93%的情况下防护林调蓄径流功能最好。目前,研究区的森林覆盖率已经达到76%,完全能够满足当地生态需要,没有必要再增加防护林的面积。但其内部结构不甚合理,以后的工作目标应当转变到调整林地结构上来。更多还原

【Abstract】 Rocky mountain area of north China is a key area of ecological construction in China, which has fragile ecological environment, serious soil and water erosion, increasing desertification, frequent natural disasters. But, the spatial layout and structural configuration of protective forest is unreasonable, which seriously prevented the play of the ecological function of protective forest. In order to optimize the space allocation of protective forest, this study combine with“study on space allocation and structure optimization technology of protective forest system”which supported by“Eleventh Five-Year”National Science and Technology, at a scale of basin, from the relation of appropriate forest coverage, proportions of forest types, space allocation and water conservation function, deeply studied the space allocation of protective forest and the relation of protective forest system and water and soil resources in Hongmenchuan Basin of rocky mountain area of north China, proposed the model of the space allocation of protective forest of typical basin.This paper is based on the hydrometeorological data of Hongmenchuan Basin in the years of 1990-2006, by using remote sensing data of four periods studied landscape features of land use of the basin in different periods.From the angel of landscape patche feature index, landscape heterogeneity index, landscape diversity index and transfer matrix of landscape types, deeply analyzed evolution characteristics of land use pattern of the basin; by using principal component analysis method, analyzed the driving factors of the landscape type change of the basin, determined and analyzed the main driving force of the land use change of the basin; then, analyzed the change law of precipitation and runoff of the basin, and studied the water conservation function of protective forest combined with the change of land use/forest vegetation.On the basis of parameter calibration, identified the applicability of SWAT model in Hongmenchuan Basin, and simulate the runoff response of collaborative change of precipitation and forest vegetation by using the model. From the sides of forest coverage ratio, propotions of forest type and space allocation, set different scenarios and simulated runoff yield of normal year, obtained the optimization program of space allocation of protective forest of the basin. The main research results are as follows:(1)During the years of 1990～2005, although forest types of Hongmenchuan Basin changed a lot, dominated by coniferous forest and broad-leaved forest. Landscape has a visible fragmentation trend, and the plaques showed a irregular trend. Sphere of influence and intensity of human factors on land use increased in the process of accelerated economic development.(2)During the years of 1990～2006, although precipitation and runoff of Hongmenchuan Basin fluctuated, showed a downward trend totally, the rate of the decrease of runoff was much larger than the rate of the decrease of precipitation. Runoff has a visible stage, the runoff in the years of 1990～1998 was larger, but the runoff in the later period was relatively small, for the land use which has a good vegetation condition, the ability of runoff yield of the later period decreased compared with the previous.(3)By the use of sensitivity analysis and automatic model calibration, studied the applicability of SWAT model in the basin, obtained a better verification. On the basis of it, simulated and obtained the collaborative response of the change of precipitation and forest vegetation, and the impact of forest vegetation change on the runoff yield of flood season and wet year was larger was discovered.The function of storing runoff of different forest types were different, the order is: shrubbery < coniferous forest < mixed forest < broad-leaved forest.(4)Five factors of landscape, slope, aspect, soil thickness and soil parent material were selected, divided site condition of Hongmenchuan Basin, 17 kinds of site conditions were obtained. Based on forest coverage ratio, 7 kinds of scenarios were set, according to site condition, carried out the space allocation of protective forest. Simulate runoff yield of different space allocations of protective forest by using SWAT model, the results showed that: when the forest coverage ratio is 70%, the runoff yield of the basin is smaller than the measured in the year of 2004, the protective forest showed a better water conservation function, and could be considered retional forest coverage ratio. And under the condition of the propotions of forest types——31.58% for broad-leaved forest, 22.96% for coniferous forest, 35.53% for mixed forest, 9.93% for shrubbery, the function of storing runoff of protective forest showed the best. At present, the forest coverage ratio of the study area has been achieved 76%, which can fully able to meet the local ecological requirements, there is no need to increase the area of protective forest. But, the internal structure is not reasonable, the objective should be converted to adjust forest structure in the future.更多还原