节点文献
哈尔滨市景观格局变化及典型小流域水土保持分析
Analysis on Landscape Change and Soil & Water Conservation of Harbin City
【作者】 刘鸿雁;
【导师】 赵雨森;
【作者基本信息】 东北林业大学 , 水土保持与荒漠化防治, 2011, 博士
【摘要】 哈尔滨市是我国最北部的省会城市,是东北部重要的政治、经济和文化中心,地处黑龙江省中南部、松嫩平原东部,全市总土地面积5.3万km2,辖八区十县。水土流失面积2.2万km2,占总土地面积的41.2%,占全省水土流失面积的16.3%,是黑龙江省水土流失严重地区之一。文章从对哈尔滨市景观格局变化及典型小流域不同水土保持措施对景观格局改变等方面进行研究。格局、功能和过程是景观生态学研究的核心内容。景观格局与生态过程的相互作用是景观生态学研究的重点。随着人口增长和社会经济的发展,景观结构和功能也产生了相应的变化,而景观斑块的形状、面积、数量和空间组合与景观中的物种分布、水土流失等生态过程密切相关,因此,探讨土地利用景观格局将有助于了解土地利用景观格局与自然、生态过程和社会经济活动之间的关系,并对土地资源的合理利用、景观的生态设计、土地利用规划、水土流失综合治理有重要意义。研究基于TM影像遥感数据,应用GIS软件Arcview和美国俄勒冈州立大学的景观格局分析软件Fragstatsv3.3,以哈尔滨市所辖范围为研究单元,从斑块面积、斑块数量、斑块密度、边缘密度、景观分维数、结合度指数、香农多样性指数和均匀度指数等方面,从斑块和景观水平对哈尔滨市土地利用景观空间格局特征进行分析。并在景观分析基础上,在不同区域选取两条不同生态恢复方向的小流域进行水土保持生态恢复研究,得到如下结果:1)研究区土地利用景观的主体为耕地,土地面积始终保持在60%以上,并呈现向外拓展趋势,流域呈现农业生态系统特征,其它依次是未利用地、草地、林地、建设用地和水域。耕地、草地和水域面积增加而林地、建设用地和未利用地减少。尤其以林地和未利用地(主要是沼泽地)向耕地转移最为突出。土地利用景观类型构成中平原区旱地占绝对地位,较高的耕地面积比例和连接度,决定其作为景观基质的地位,说明农业在经济发展中仍具重要的作用。2)斑块密度分析显示,农村居民点数目众多,分布分散,破碎化程度高,在景观中分布广泛,影响景观内其他多种生物的生存。边缘密度、分维数和连接性分析表明,耕地斑块边缘和几何形状相对复杂,结合度较高;林地斑块边缘和几何形状简单,但结合度高,连接性较好。3)从景观类型水平上,研究区草地、水域和建设用地的破碎化指数略有下降或持平,耕地、林地和未利用地景观破碎化指数的上升,尤其是耕地该指数增幅较大,集中反应出耕地面积和格局的变动,对整个流域的各类土地利用景观有显著影响,耕地与其他各类土地利用景观关系更加密切,同时反应出人类活动对流域景观的稳定性和可持续发展影响较强。4)水域、沼泽面积大幅度减小,新技术的开发应用使很多难利用土地迅速减少,土地利用向平原区水田景观要素集中。5)研究区斑块数量增加、景观分割度、分离度指数SPLIT等指数增大,斑块平均尺寸MPS、散布及并列指数IJI、有效粒度尺寸MESH和香农多样性指数SHDI、Simpson’s多样性指数SIEI和聚合度AI减小,表明流域景观的实际变化情况,变动趋势对区域生态系统功能发挥不利。说明耕地迅速增加对流域景观格局的变化产生了重要作用,景观格局的变化对区域生态环境和社会产生了不良影响。6)小流域的土地景观格局是自然地理和人类活动干扰的结果。调整小流域土地景观格局,提高景观类型的多样性,在空间上建立多层次的结构能充分利用环境资源的异质性,形成新的生态系统结构,可以增强流域生态系统的稳定性。7)两条采取不同生态恢复方式的小流域,通过恢复,小流域生态系统趋于稳定,景观格局发生改变。仅仅采用封禁、封育是不能快速实现生态修复和水土保持目标的,生态恢复需要一个漫长的过程,在短期内不能发挥出良好的生态和经济效益,我们可以采取人为加速修复的办法。8)实施生态修复工程后,小流域景观中没有明显的景观优势类型,而且斑块类型在景观中分布比较均匀,小流域生态交错带的景观特征更明显,小流域生态系统更稳定。9)与全部是水土流失重点治理模式相比,水土保持生态修复在恢复生态系统方面具有较好的效果。在水土流失地区,通过制定政策、强化管理和辅以人工促进措施,消除不合理的人为干扰,促使自然界本身固有的再生能力得以最大限度的发挥,促进植被的生长发育和发展演替,保护和改善受损的生态系统的结构、景观和功能,加快水土流失防治步伐,建立和维系与自然条件相适应、与经济社会可持续发展相协调、相对稳定并良性发展的生态系统。10)今后哈尔滨市水土保持发展模式应在构建科学完善的水土流失防治体系基础上实施保护优先战略、综合治理战略和科技支撑战略,重视实施项目的发展,坚持以水系划分项目区,加快坡耕地水土流失治理生态修复和重点治理相结合,保障粮食安全,依法严格保护水土资源和生态环境。
【Abstract】 Harbin is located in the center of southern Heilongjiang Province, on the east of Songnen Plain. Covering 53,000 square kilometers, Harbin has jurisdiction over eight districts and ten counties. Urban areas of Harbin and Shuangcheng are flat, low-lying while eastern parts are mountainous, with Xiaoxing’anling in the north. Songhua River flowing through its central part and low mountains being scattered around, rivers and vast plains mainly cover the area. The city is one of the most severe soil erosion areas in Heilongjiang Province, which covers 2.2 million square kilometers, accounting for 16.3%of the province’s soil erosion area and 41.2% of the total land area.Structure, function and process are the core of landscape ecology. The interaction of landscape patterns and ecological processes is the focus of landscape ecology. With population growth and socio-economic development, landscape structure and function have also taken a corresponding change, though, the shape, area,volume and space combination of landscape patches are closely related with species distribution, soil erosion and other ecological processes,So by studying the use of landscape pattern will help not only in prodding the relationship between the landscape pattern and nature, ecology and social economic activity but in the rational use of land resources and soil erosion control.The research,based on TM remote sensing image data, coupled with applications of GIS software Arc view and landscape pattern analysis software Fragstatsv3.3 of Oregon State University,will analyze the characteristics of Harbin landscape spatial pattern of land use in the patch and landscape level, the research unit under the jurisdiction of the range, from the aspect of patch area, patch number, patch density, edge density, landscape fractal dimension, combination index, Shannon diversity index and evenness index, etc. And based on landscape analysis, we selected two small watersheds in different areas fewer than two directions in ecological restoration of soil and water conservation for contrast and the results are as follows.1) The main part of the area under study is arable land, which is always maintained at 60% or more, and shows a trend of outward expansion, characteristic of agro-ecosystems, other landscapes following by are unused land, grassland, forest land, construction land and waters. As arable land, grassland and water area increased, woodland, construction land and unused land decreased. Particularly woodland and unused land (mainly swamp) land transferring to cultivated land are the most prominent. In composition of landscape types of land use, plain dry land occupy absolute position, the higher proportion of cultivated area and connectivity determine its status as the landscape matrix, illustrating that agriculture remaining play an important role in economic development. 2) The patch density analysis shows that a large number of rural settlements are scattered, highly fragmented, widely distributed in landscape, and affects a variety of other creatures’ survival in landscape. Edge density, fractal dimension and connectivity analysis showed that the patch edge and geometry of cultivated land is relatively complex, with high combined degree; while forest patch edges and geometric shapes is simple, with higher combination and better connectivity.3) In study area, fragmentation index of grassland, water, and construction land decreased slightly or flat in landscape level, while arable land, forest land and unused land increased, especially farmland index which increased considerably, concentrated reaction the changes of cultivated area and pattern significantly affected the various land use landscape in the entire basin, farmland has closer relationship with other types of land use and landscape, while reflecting strong influence of of human activities on landscapes stability and sustainable development.4) Water, marsh area is reduced seriously, so as the hard-used land as the development and application of new technologies, and land-use converges to landscape elements of plain paddy field.5) In the study area, while the number of patches, degree of landscape division, separation, SPLIT index and other index increasing, the mean patch size MPS, distributed and parallel index IJI, the effective grain size and Shannon diversity index MESH SHDI, Simpson’s diversity index SIEI and polymerization degree AI will decrease, indicating that the actual changes in the landscape, the changing trends play a negative domain to ecosystem functions throughout the region. Rapid increase in farmland landscape has an important role in the landscape pattern diversification; pattern changes of the basin had a negative impact on regional ecological environment and society.6) Interference of natural geographical and human activities resulted in land landscape patterns of small watershed. Adjusting the small watershed landscape pattern and improving the diversity of landscape, creating a multi-level structure in the space can take full advantage of the heterogeneity of environmental resources, and form new ecosystem structure, can enhance the ecological system stability.7) Taking different ecological restoration, two small watershed ecosystems stabilized and landscape pattern changed. The aim of ecological restoration and soil and water conservation can’t be reached just taking the measures of fencing and closing hillsides to facilitate afforestation. Ecological restoration is a slow process; it can not bring better ecological benefit and economic benefit in a short time. However, we can take measures of artifical to accelerate ecological restoration and soil and water conservation.8) After the implementation of ecological restoration, there is no obvious advantage type of landscape, and patch types are more evenly distributed across the landscape, watershed eco-tone features of the landscape are more obvious, and eco-system is more stable.9) Compared to key soil erosion control with all anthropogenic interference ecological restoration, the soil erosion area, through policy and strengthened management, supplemented by artificial promotion of measures eliminated unreasonable disturbance, promoted the inherent regenerative capacity of nature to maximum, protected and improved the structure, landscapes and features of damaged ecosystems, thus establishing and maintaining an ecological system compatible with natural conditions, and coordination of economic and social sustainable development, which is relatively stable and healthily developed.10) Harbin soil and water conservation in future development pattern should implement conservation priority strategy、comprehensive control strategy and science and technology support strategy on the base of constructing completely scientific soil erosion prevention and control system. And pay more attention on project implementation development; adhere to the water system division project; combine soil and water loss control and ecological restoration with key harness in sloping farmland ensure food safety. And protect water and soil resources and ecological environment according to law.
【Key words】 Harbin; landscape pattern; ecological restoration; small watershed; erosion;