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1.
区域森林生态系统服务功能评价——以山东省为例   总被引:20,自引:0,他引:20  
生态退化、环境破坏是区域可持续发展的重要制约因素,山东省作为我国经济增长 最快的省份之一,森林生态系统在维护环境和提供生态服务方面发挥着尤为重要的作用。作 者采用市场价值、替代工程等方法基于县域尺度对山东省各地区森林生态系统的生产、游憩 、改善大气环境、水土保持等服务功能进行价值评估,在游憩功能评价中从与以往不同的角 度建立了新的价值评估指标。在森林生态系统服务功能价值计算的基础上,从结构、密度、 质量3方面建立了6项评价指标,采用多边形综合指标法对山东省各地区森林生态系统服务功 能进行综合评价与分级,在此基础上,针对不同地区提出了相应的措施与建议。  相似文献   

2.
城市森林生态系统生态服务功能的评价   总被引:14,自引:3,他引:14  
运用森林生态系统生态服务功能评价的方法,依据社会—经济—自然复合生态系统理论和生态规划原则及昆山市森林生态系统规划的要求,对昆山市森林覆盖率、人均森林面积、人均公共森林面积、公益林所占比例、森林均匀度、综合生态价值6个指标分阶段进行了分析。并采用多边形综合指标法评价了昆山市森林生态系统生态服务功能,提出了提高生态服务功能的建议。  相似文献   

3.
可持续发展的生态评估是当前国际生态经济学与可持续发展研究的前沿问题之一。甘肃南部区域的自然地理背景复杂,生态系统类型多样。以县级行政区为评价单元,选取相关评价指标,核算了森林、草地、荒漠、农田、湿地和城市6大类生态系统在气体和气候调节、水源涵养、土壤保持、环境净化、生物多样性维护、生物产品产出、文化娱乐7个方面的生态服务价值。评价结果表明,全省84个评价单元的生态服务价值的空间格局明显,较好地表现了各地区的生态系统的重要性及其分区指向,其结果可为省级主体功能分区提供基本依据。作为一种思路和方法,在完善主体功能分区中是值得探讨的。  相似文献   

4.
基于森林生态系统连续观测与清查体系,依据中华人民共和国林业行业标准《森林生态系统服务功能评估规范》(LY/T 1721-2008),并结合2016年上海市森林资源监测成果数据,对上海城市森林生态系统服务功能价值进行了评估.结果表明:2016年上海市森林生态系统服务功能总价值为125.8亿元,每公顷森林提供的价值量为12.75万元.8项森林生态系统服务功能价值量从大到小的顺序为:森林游憩(26.03%)净化大气环境(22.03%)固碳释氧(20.24%)涵养水源(17.14%)生物多样性保护(9.10%)保育土壤(3.53%)林木积累营养物质(1.84%)森林防护(0.09%).从研究结果来看,森林游憩功能的价值量最高.森林游憩、净化大气环境、固碳释氧和涵养水源是上海城市森林生态系统服务功能的主体功能,对于上海市营造宜居型城市及创建"生态之城"具有重要作用.  相似文献   

5.
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   

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.
森林生态系统服务功能价值评估对促进林业可持续发展具有重要意义。利用遥感数据与GIS空间统计分析方法,分析贵州省2015年森林生态系统服务功能价值及空间分布特征。结果表明:1)贵州省森林生态系统服务功能价值量高达6 167亿元,各功能价值量排名为固碳释氧、生物多样性保护、净化大气环境、涵养水源、固土保肥、游憩、积累营养物质;2)生态系统服务功能价值量在市域水平上的空间分布呈现出北部遵义最高,东南部黔东南、黔南较高,中西部较低,西部六盘水市最低的分布态势,这一特征与当地地势条件与人类活动强度相关;3)黔东南、黔南自治州等部分地区应进一步依托森林生态系统服务功能价值较高的优势,大力发展林业绿色产业,走兴林富民道路;加强面向生态系统服务功能的林业大数据系统建设,为完善生态文明体制机制提供数据支撑。  相似文献   

8.
黄河三角洲高效生态经济区生态系统服务价值评估   总被引:1,自引:0,他引:1  
采用谢高地分类系统和评价方法分析了黄河三角洲高效生态经济区生态系统服务功能及其价值,分析了生态系统服务价值的区域分布,并与Costanza分类系统和评估方法进行了对比。从生态类型来看,湿地、森林、农田和草地生态系统服务价值分别占总价值的63.3%,20.7%,15.6%,0.43%。从生态服务功能来看,废物处理、气候调节、水源涵养等方面的价值较大,分别占总价值的23.37%,21.88%,20.08%。  相似文献   

9.
【目的】评估江苏省重点公益林的生态服务功能及价值。【方法 】依据《森林生态系统服务功能评估规范》(LY/T 1721— 2008),利用江苏省森林资源二类调查资料,以及长江三角洲森林生态系统定位研究站长期监测数据和相关研究成果,对江苏省重点公益林生态服务功能及价值进行评估。【结果】江苏省重点公益林生态服务功能总价值为400.63亿元/a,是每年投入的257倍。各项生态服务功能价值大小次序为:涵养水源价值>固碳释氧价值>生物多样性保护价值>森林游憩价值>积累营养物质价值>净化大气环境价值>森林防护价值>保育土壤价值。针叶类树种以及梨、柿、板栗、杜仲、油桐等经济树种生态服务功能较高,其他硬阔及杨树面积大,但其单位面积生态服务功能价值均较低。【结论】公益林分布区应适当将杨树、其他硬阔树种等更新为针叶类,或者梨、柿、板栗、杜仲、油桐等经济树种,以提高江苏省重点公益林的生态服务功能价值。  相似文献   

10.
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   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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