摘要
森林生态系统是人类生存与发展的基础,其服务功能不可替代。以南水北调中线工程渠首所在地淅川县为研究区,使用2004年TM、2009年TM、2014年GF1号影像等数据,在PIC、Arcgis10.0等软件支持下,分析其2004—2014年的林地资源变化,并利用InVEST模型对森林生态系统服务功能(水源涵养、水质净化和土壤保持)进行定量评估。结果表明:(1)2004—2014年县域林地资源以有林地为主,面积增长迅速,灌木林地和苗圃地面积增长缓慢,疏林地和未成林造林地面积均呈现先增后减趋势;(2)伴随林地资源变化,森林生态系统服务功能产生相应显著变化,10年间县域水源涵养量功能减少19%,森林水质净化功能提高29%,土壤保持功能增加6%;(3)同一森林类型,其生态服务功能在不同年际之间的差异表现为平均水源涵养功能逐年下降,平均水质净化能力不断提升,平均土壤保持能力先增后减;(4)对比5种森林类型的生态服务功能,有林地的服务功能最强,其次为灌木林地和疏林地;(5)10年间县域森林生态系统的水源涵养、水质净化和土壤保持服务功能的高低与森林覆被的高低程度呈正相关,呈现出北高南低的空间分布格局;(6)科学管理森林生态系统服务的关键在于合理配置林地与其他用地的分布格局,提高林地与其它用地镶嵌构成的复合土地利用的可持续性。同时加强服务功能重要区域的保护,避免对对服务功能较差区域的破坏。此外,未来森林经营需要从单纯的森林面积扩张,转变为提高森林质量和生产力,从而加强森林生态系统对气候变化影响的适应能力。
Because forest ecosystems and the services they provide cannot be replaced,the main purpose of forest maintenance and management is to protect forests,as a basic resource for human survival and development. As a case study,the present study investigated Xichuan County,which is the main source of water for the middle route of the southto-north water diversion project,by quantitatively analyzing changes in forest resources from 2004 to 2014,using TM and GF1 image data from 2004—2009 and 2014,respectively. On the basis of previous analyses,the InVEST model was used to quantitatively evaluate the ecosystem function of the forest（ water conservation,water purification,and soil conservation）.The results indicated that the area of forest increased rapidly,by 10.85% from 2004 to 2009 and by 7.44% from 2009 to2014,which resulted in a forest area of 45.65% by 2014. From 2004 to 2014,the closed forest land of the county increased as well,whereas the area of shrubland and Nursery woodland increased more slowly,and the area of sparse woodland and non-wooded land both tended to increase and then decline in succession. As the forest resources changed,significant changes were also observed in the corresponding ecosystem functions,including 10-year water purification,which increased by 29%; water conservation,which increased by 19%; and soil conservation,which increased by 6%. Meanwhile,among the individual forest types, the average water conservation function decreased annually, whereas the average water purification capacity continuously improved,and the average soil holding capacity initially increased and subsequently decreased. Forest was the main type of landscape cover in the region,as well as the main contributor to total ecosystem function,followed by shrubland and sparse forest. During the study period,areas that contributed to the county＇ s water conservation,water purification,and soil conservation services were strongly and positively correlated with forest area,and both improvement and expansion of forested areas enhanced the ecological services provided. In addition,the spatial distribution of the forest＇s ecosystem function was greater in the north than in the south. Analysis of the history and current condition of forest ecosystem management in the study area indicated that the key managing forest ecosystem service lies in maintaining an appropriate distribution of forestland and other land types,and the ecological function of the forests was affected by both forest area and structure（ e. g.,crown density,soil thickness,soil, root depth）, as well as by meteorological factors. In order to improve forest quality and productivity,future forest management strategies need to promote the expansion of pure forestland and transformation and implement changes that will improve the ability of the forest ecosystem to adapt to climate change.
出处
《生态学报》
CAS
CSCD
北大核心
2017年第20期6973-6985,共13页
Acta Ecologica Sinica
基金
国务院南水北调工程建设委员会办公室2015年技术咨询委托项目
