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61.
达里诺尔国家级自然保护区游憩服务功能价值评估 总被引:10,自引:0,他引:10
对自然资源价值的评估是监测自然资源的保护与可持续开发利用效果的理论基础。文章以内蒙古赤峰市克什克腾旗达里诺尔国家级自然保护区为研究对象,运用旅行费用法对达里诺尔国家级自然保护区的游憩服务功能进行了价值评估,计算出其游憩总价值为7517万元。这一结果可为达里诺尔国家级自然保护区的资源决策和资源补偿提供一定的参考。 相似文献
62.
位于滇西南德宏州的省级瑞丽江自然保护区总面积73 500hm2,主要保护对象是季节雨林、石灰山季雨林、季风常绿阔叶林、珍稀濒危物种、水资源及自然景观。介绍了保护区丰富的资源、管理现状、存在问题,提出了今后发展思路。 相似文献
63.
This study focuses on the problem of irregular diameter structure in a silver fir–beech selection (plenter) forest with a “surplus” of large diameter trees and a lack of natural regeneration and small diameter trees. We sampled 274 plots (900 m2 each) in the Belevine research site (266.24 ha) in the mountain region Gorski Kotar (Croatia), where diameter (dbh) distribution, diameter increment, and natural regeneration were analyzed in detail. A low density of natural regeneration, weak annual recruitment of small (10 cm dbh) diameter trees (only five trees per hectare), delayed diameter growth of trees, and a low annual rate of trees reaching the next dbh class were attributed to the current irregular dbh structure. The stand development prediction for the next 50 years is based on a simulation model, which considers the current diameter structure, increment, recruitment, and future cutting regime. Intensive cutting in the first of five 10-year cutting cycles (intensity higher of 25%) is needed to initiate natural regeneration and to accelerate growth of young silver fir trees. In the next 50 years, the irregular diameter structure will be gradually improved. 相似文献
64.
65.
调查统计表明,箬寮岘自然保护区珍稀濒危植物及国家保护植物有28种,隶属于18科25属。通过对箬寮岘自然保护区28种珍稀濒危植物及国家保护植物区系组成的分析,得出该区系具有木本植物占优势、区系起源古老、孑遗植物众多、地理成分复杂和特有现象显著等特征。 相似文献
66.
Walter Sekot 《European Journal of Forest Research》2007,126(4):481-494
Within the European Union there exist three different frameworks for forest accounting at the national level. For purposes
of the national accounts, the regulations of the European System of Integrated Economic Accounts (ESA) have to be observed.
They require a distinction between forestry and logging and provide specific guidelines for the valuation of standing timber.
In recognition of the special character of forests and forestry production, two satellite accounts are devoted to forestry:
the Economic Accounts for Forestry (EAF) and the European Framework for Integrated Environmental and Economic Accounting for
Forests (IEEAF). Although they were designed as complementary to the national accounts and refer to the same basic methodologies,
the guidelines for forest accounting provided by the three manuals are not fully compatible. Just recently, a further integration
and harmonization of the concepts for forest accounting has been proposed. Austria has implemented the valuation of the increment
as an output of forestry as requested by ESA and produces the EAF tables on a regular basis. The possibilities for extending
forest accounting to natural resource accounts for standing timber and the IEEAF have been investigated in terms of pilot
studies. The Austrian experiences and results exemplify the problems and possible solutions associated with the adoption of
the different European schemes. Data deficits and valuation issues restrict the significance of respective results to some
degree, especially as regards forestry-specific extensions of the accounting schemes. 相似文献
67.
Four populations representing the entire natural distribution range of Pinus brutia (Ten.) in Crete (Greece) were sampled to determine: (1) Altitudinal variation within populations of Lassithi, Vorizia, Koustagerako, and Samaria, and; (2) Longitudinal variation among the four populations, based on morphological and anatomical differences in cone, needle and seed characteristics. Samples were collected from 10 trees per altitude, at three altitudes in each population. A total of 12 morphological and anatomical traits from needles, cones and seeds were analyzed to assess the altitudinal and longitudinal variations of the species in the island. The number of teeth per cm showed significant (P<0.01) differences between altitudes in Samaria, Vorizia and Lassithi, while needle length, width and the number of resin canals showed significant differences (P<0.01) between altitudes in Koustagerako. Cone width showed patterns of variation along the altitudinal gradient in Koustagerako, Samaria and Vorizia. Most traits had their highest means at the middle altitudes (650masl) in all the four populations. Overall, no clear altitudinal differentiation was detected, probably due to high rate of gene flow. Longitudinal variability showed a clear pattern of differentiation along the east–west climatic gradient. Needle length, width, sheath length, number of teeth per cm and the number of resin canals were the most useful traits for determining the climatic gradient clines. 相似文献
68.
69.
南方岩溶区植被自然演替恢复研究综述 总被引:2,自引:0,他引:2
我国岩溶区绝大部分分布在南方。植被的自然演替恢复是岩溶区生态重建的主要方式。随着自然演替的进行,土壤环境特征、土壤养分特征及土壤种子库等产生相应的变化。而岩溶植被的顶极群落特征和群落演替特征,包括盖度、结构、物种多样性、生物量、分布格局、演替方向都有其自身的特殊性。 相似文献
70.
罗平万峰山自然保护区的景观旅游资源及开展生态旅游设想 总被引:2,自引:0,他引:2
介绍了罗平万峰山自然保护区的实验区及其周边丰富的景观资源,分析了保护区开展生态旅游的有利条件,并提出了开展生态旅游的设想。 相似文献