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1.
云和县森林生态系统水源涵养功能评估   总被引:3,自引:0,他引:3  
云和县是浙江省的重要生态功能区,具有十分重要的水源涵养功能.以浙江省云和县2007年森林资源二类调查数据为基础,结合文献参数数据,运用综合蓄水能力法,估算云和县林冠层、枯落物层和土壤层3个不同作用层的水源涵养量,并对不同森林类型、林龄、立地条件下森林涵养水源功能以及空间分布进行对比分析.结果表明:1)2007年云和县森林生态系统总涵养水源量为7584.49×104 m3,其中94.18%来源于土壤层蓄水,4.19%来源于林冠截留降水,枯落物层枯落物层持水量占1.63%;2)各森林类型总涵养水源量大小依次为阔叶林>松木林>杉林>经济林>竹林>灌木林,单位面积涵养水源量平均为908.49 t/hm2,大小依次为阔叶林>竹林>杉林>松木林>经济林>灌木林;3)水源涵养林不同年龄组的贡献率为幼龄林(43.60%)>中龄林(26.91%)>近成熟林(22.27%)>成熟林(6.93%)>过熟林(0.29%);4)云和县森林生态系统的综合水源涵养能力呈现四周高、中间低的空间分布特征,与海拔的分布特点一致.  相似文献   

2.
九寨沟森林生态系统水源涵养量计算分析   总被引:4,自引:1,他引:4  
目前,在整个陆地生态系统中研究最多的就是面积量很大的重要的森林生态系统,综合考虑涵养量估算技术和实用目的,本文提出森林水源涵养量就是森林拦截的可提供给人们利用的水量的定义,通过对森林水源涵养量概念厘定,结合九寨沟森林生态系统的实例,对九寨沟森林生态系统水源涵养状况进行分析,对九寨沟森林水源涵养量进行了估算.结果表明:九寨沟森林生态系统的年水源涵养量为1.60219×1012 m3 由此可见,在地区可持续发展进程中,森林生态系统的生态价值还是十分重要的.  相似文献   

3.
以巴尔鲁克山自然保护区的森林生态系统为研究对象,从物质量与价值量的角度,采用影子工程法、机会成本法、市场价值法等研究方法,对巴尔鲁克山自然保护区森林生态系统生产有机物、涵养水源、保育土壤、固碳释氧、净化环境、营养元素积累、生物多样性保护、森林游憩这8项功能12个指标进行价值量评估,最后算出研究区森林生态系统服务功能总价值和单位面值价值。结果表明:该自然保护区森林生态系统服务功能总价值为:7.05×108元·a-1,单位面积价值为:3.08×104元·hm-2·a-1。其中,直接经济价值为0.5×104元·a-1,占总价值中的7.04%;间接价值总和为6.6×104元·a-1,占总价的92.96%。各项功能价值的大小顺序为:固碳释氧价值涵养水源价值生物多样性保护价值保育土壤价值游憩价值积累有机物价值净化环境价值生产有机物价值。  相似文献   

4.
涵养水源是森林生态系统的重要功能之一,其维持区域水资源安全的作用十分明显,作为东北多条江河的发源地,在吉林省内此功能的作用更为重要.采用2006,2011和2013年吉林省森林资源数据和森林生态站及辅助观测样地的长期监测数据,对吉林省森林生态系统涵养水源功能进行时空动态研究.结果表明:1)吉林省森林生态系统的水源涵养功能在逐渐提升,2006,2011和2013年吉林省森林生态系统涵养水源量分别为175.06万m~3/a,185.14万m~3/a和197.28万m~3/a; 2)吉林省森林生态系统涵养水源功能呈现出东部中部西部的空间分布格局; 3)影响吉林省森林生态系统涵养水源功能时空格局的驱动因子为森林资源面积、森林资源质量、森林资源结构(起源和林龄)、气候因素和林业政策(尤其是林业生态工程).本研究能够为吉林省生态建设和林业政策的制定提供理论依据,继而使森林生态系统发挥更大的涵养水源作用.  相似文献   

5.
对森林公园生态系统服务功能进行评估,有助于人们了解其重要性和制定有效的森林资源保护政策。本文研究依据《森林生态系统服务功能评估规范》(LY/T 1721-2008),采用福州国家森林公园的小班数据和实地调查数据,应用分布式测算的方法,对其2013年固碳释氧、涵养水源、保育土壤、净化大气和森林游憩5项服务功能进行评估。结果表明:(1)福州国家森林公园生态系统服务的总价值为6. 84亿元/a;(2)价值量由高到低的顺序为:森林游憩(4. 0960亿元/a)固碳释氧(1. 041亿元/a)涵养水源(0. 9983亿元/a)保育土壤(0. 7001亿元/a)净化大气(56. 94万元/a),其中,森林游憩的价值最高,占总价值的59. 87%,其次为固碳释氧,占总价值的15. 22%;(3)单位面积幼、中龄林的固碳释氧价值量的比重大,过熟林最低;(4)不同林分类型单位面积的4种服务功能(除森林游憩外)相比,软阔价值量最高,为11. 99万元/(hm~2·a),经济林最低。根据本文研究结果提出以下建议:对福州国家森林公园过熟林采取间伐补植、异龄混交的林业经营措施,同时适当进行阔叶树种补种,提高林分的生态价值。  相似文献   

6.
根据森林生态系统服务功能评估规范(LY/T1721-2008),将崇左市森林生态系统服务功能价值划分为生物多样性保护、涵养水源、固碳释氧、净化空气、保育土壤、森林休憩及营养累积7个类别,以崇左市2015年统计年鉴数据、2014年林地变更数据、2015年崇左市森林资源主要数据更新数据和相关森林生态连续观测数据及社会公共数据为参数,评估崇左市森林生态系统服务功能的总价值。结果表明:2015年崇左市森林生态系统服务功能价值总量为549.59亿元人民币,单位面积生态服务功能价值为57 918.29元,7项生态服务功能价值的排序依次为:涵养水源生物多样性保护固碳释氧净化空气保育土壤森林游憩营养累积。不同林分类型单位面积生态系统服务功能价值由大到小的顺序为:石山灌木林松类一般阔叶林速生桉八角林硬阔叶林农地乔木及四旁树土山灌木林乔木经济林杉木类一般桉竹子灌木经济林栎类速生相思。  相似文献   

7.
武夷山自然保护区森林生态服务功能价值评估   总被引:1,自引:0,他引:1  
使用市场价格替代法、机会成本法和影子工程价格法等评估方法,对武夷山自然保护区森林涵养水源、保持土壤、净化空气、固碳制氧等服务功能进行初步估算.得出该地区森林生态系统的涵养水源价值为2.28亿元.a-1;保持土壤价值为0.76亿元.a-1;固碳制氧价值为2.20亿元.a-1;净化空气价值为1.76亿元.a-1.森林生态服务功能的总价值为7.04亿元.a-1.  相似文献   

8.
江西广丰森林生态服务及其价值研究   总被引:2,自引:0,他引:2  
王兵  王丹 《江西科学》2010,28(5):630-637,687
森林生态服务功能评估是国内外研究的热点之一,依据森林生态服务功能评估标准,采用森林生态系统定位研究网络台站多年连续观测数据和森林资源清查数据及公共数据、实测数据对广丰县森林生态服务功能物质量和价值量及其变化进行了评价,并分析其变化原因。结果表明,广丰县生态效益价值为46.75亿元/a,大于江西省平均值,占全县GDP的36.52%,但除涵养水源功能等以外,其它12项功能总物质量均小于江西省平均值;不同林分类型生态服务功能物质量不同,各项均呈现出马尾松最大,灌木林、经济林、竹林较大,国外松、软阔类较小的明显变化规律,主要由林分面积和林分单位面积生态服务功能物质量不同造成;与全省平均值相比,广丰县单位面积生态效益价值增加了2.48%,达到5.38万元.hm-2.a-1,各林分类型大小顺序为混交林竹林灌木林硬阔类经济林马尾松国外松软阔类杉木。  相似文献   

9.
以云南省保山市为例, 利用CHELSA全球月降水量和月平均气温数据(900 m分辨率)以及MOD17A3 NPP数据和HWSD-V1.2土壤数据, 基于Budyko水平衡模型, 定量地评估区域水源涵养功能的空间分布状况。研究结果表明, 研究区的水源涵养量空间分布主要受降水空间分布不均影响, 其中高黎贡山的阻隔对水汽分布起重要作用; 不同地类的单位水源涵养量和总水源涵养量排序均为森林>灌草地>耕地>水域>建设用地。森林的保护和维持对区域水源涵养能力的提升至关重要。研究区水源涵养极重要区占市域面积的14%, 且集中于高黎贡山西侧, 东侧大部分区域水源涵养能力较弱, 水资源涵养功能维持的压力较大。  相似文献   

10.
青海省门源县森林生态系统服务功能价值评估   总被引:1,自引:0,他引:1  
依据森林效益监测数据、森林生态系统长期连续定位观测数据、森林资源调查数据和国家权威机构公布的社会公共数据,采用《森林生态系统服务功能评估规范》评估模型,对2013年青海省门源县森林生态系统服务功能价值进行评估。结果显示:森林生态系统服务功能总价值为293.63亿元/a;各生态系统服务功能价值大小顺序为:保育土壤生物多样性保护涵养水源净化环境固碳释氧森林防护森林游憩积累营养物质;单位面积年服务功能价值为9.257 2万元/(hm2·a)。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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