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1.
Conservation contracting has attained growing interest worldwide as a tool for protecting biodiversity in privately owned lands. In this policy, landowners receive payments from an environmental agency in exchange for land use practices that contribute to the supply of biodiversity. This approach may result in a conservation network which does not cover all focal ecological characteristics, because landowners determine the supply of potential targets. In addition, the contracts are typically allocated by using a scoring method that is not giving information on the representativeness of the species composition of the sites. In this study, we investigated what is the performance of a voluntary conservation program in selecting sites that would maximize the number of specific target species in the selected conservation network subject to a given budget constraint. We focused on the Finnish pilot program named Trading in Natural Values (TNV). Our data consisted of 56 mature stands covering both stands that were offered to the TNV program and stands that were not offered. All the stands were surveyed for specific groups of wood-inhabiting fungi and epiphytic lichens that can be considered as good surrogates for forest species diversity.Our results showed that the participation in the TNV program was large enough to meet the ecological goals, because the offered targets uncovered only two of the 73 surveyed species, and the cost-effective conservation network included only a few targets that were not offered in the pilot program. However, the contract allocation method used in the TNV could be improved, because many ecologically valuable targets that were offered to the program were not accepted. In general, it could be justified to survey some indicator species, which would be relatively easy to identify, to maximize species coverage in contract allocation. Surveying indicator species causes some extra costs, but these are likely to be minor compared with the costs savings in opportunity costs, due to the improved targeting of protected areas.  相似文献   

2.
Safeguarding biodiversity has been one of the most important issues in environmental and forest policies since the 1990s. In Southern Finland, decisions concerning further actions for the preservation of forest biodiversity will be made in the coming years. To support policy making, we present a multi-regional model that is applicable in determining the economically optimal regional allocation of conservation sites. Three habitat quality models are evaluated to calculate habitat quality indices used as a surrogate for a biodiversity value in a forest sector model. The scenarios presented provide information about the economic impacts of conservation choices on the forest sector. The overall economic impacts of conservation depend on its scale and regional allocation. Conserving land with high biodiversity value can have less adverse impact on the forest sector than conservation of typical commercial forest sites. When optimizing conservation set-asides, we found that set-asides targeted to certain regions possessing higher/lower than average relative share of ecologically valuable land, caused lower/higher adverse economic impacts on the forest sector. Because it is expensive to search land suitable for conservation, these regions could be respectively favoured/avoided when asking forest owners to offer their land for the new conservation program in Southern Finland, which will be based on voluntariness.  相似文献   

3.
We analyze the problem of choosing sites through time to include in a network of biological reserves for species conservation. When sites cannot all be protected immediately, and excluded sites are threatened by development, planning should factor in both expected biodiversity benefits of sites and development risk. We formulate this problem as a stochastic dynamic integer-programming problem. We find that the timing of selections is critical; conservation budgets available up front yield significantly greater biodiversity protection. We also compare results using optimal and heuristic algorithms. The theory is applied to vertebrate and development threat data from southwestern California.  相似文献   

4.
To halt the decline of biodiversity in New Zealand, the government has formulated a strategy of maintaining and restoring a full range of remaining natural habitats to a healthy functioning state. Many indigenous forest remnants exist on private land, and these could be utilised to increase biodiversity. Resources for conservation of forest remnants are limited, so they must be used wisely to deliver the greatest possible biodiversity gain. This paper presents a rapid method for valuing the biodiversity of a region's indigenous forest remnants to help prioritise conservation resources. The region is divided into environmentally distinct areas called land environments. A detailed land-cover map is derived from satellite imagery and used to estimate the proportion of natural habitats remaining in each land environment; from this the biodiversity value of any forest remnant may be calculated. The method is rapid and does not require detailed biodiversity information. When combined with conservation costs, it may be used to create a priority list of forest remnants for conservation. The Manawatu/Wanganui region of New Zealand is used as a case study to demonstrate the method.  相似文献   

5.
Nature reserves not only protect habitat-stressed species but also provide recreation and welfare services to people. Therefore, site accessibility matters in reserve design. This study incorporates public accessibility, determined by urban populations and distances between urban areas and reserve sites, as an additional factor in conservation reserve design besides species representation and economic characteristics of individual sites. An optimization approach is introduced to determine a reserve network with maximum accessibility while satisfying specified representation targets under financial constraints. The paper also presents an empirical application of this approach to endangered/threatened birds in Illinois, USA, and analyzes the tradeoffs between ecological, economic, and social objectives of biological conservation. The results show that: i) the conventional minimal representation approach would result in a small reserve network, but this network would have poor accessibility; ii) public accessibility can be improved significantly by selecting alternative sites with the same amount of conservation budget; iii) further improvement in accessibility can be achieved by enlarging the network, but in this particular case the gains would be insignificant after the first few additional sites; and iv) a regionally integrated conservation plan, as opposed to decentralized conservation efforts, is beneficial for both species protection and social welfare.  相似文献   

6.
Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.  相似文献   

7.
荒野地,是大面积的、保留原貌或被轻微改变的自 然区域,具有保护生物多样性和维持生态系统服务等多元价 值,因此具有重要的保护意义。在“2020年后全球生物多样 性框架”中,荒野保护是重要的行动目标之一。在此新背景 下,分析了中国荒野地保护中存在的五大现状问题,包括荒 野价值认知不足、荒野本底状态不清、荒野保护空缺明显、 荒野地破碎化严重、荒野地管理质量较低。在此基础上,提 出了中国荒野地保护的目标和系统性保护策略(包括主流化策 略、普查策略、全域分级保护策略、连通策略和提质策略), 以及相应的12项行动建议,有望为我国开展系统性的荒野保 护提供思路。  相似文献   

8.
城市化进程的不断加快影响了城市绿色空间的生境 质量,城市生物多样性受到极大威胁。构建城市范围内的多物 种综合生境网络能够整合现有的城市绿色空间格局,促进生物 多样性保护与发育。以北京市丰台区为例,面向生物多样性保 护与城市绿色空间发展提出了基于InVEST-MCR复合模型的 城市绿色空间生境网络格局构建方法体系:即以生境类型为导 向选取区域内生物多样性保护的焦点物种,通过大数据选取焦 点物种的栖息源地,基于InVEST模型生境质量模块选取潜在 栖息地(汇)并生成生境网络构建阻力面,采用最小累计阻力 模型(MCR)构建丰台区城市绿色空间生境网络。研究结果明 确了丰台区的生境质量现状与未来生境网络发展脉络,为城市 绿色空间生境网络构建提供了新方法,为丰台区绿地空间格局 规划与生物多样性保护提供了参考框架。  相似文献   

9.
The Convention on Biological Diversity’s (2010) target to reduce the rate of biodiversity loss was achieved by very few countries. Why? We use the theory of conservation implicit in the Hotelling model of non-renewable resource pricing to analyze the problem, distinguishing between the benefits to countries where conservation takes place, and to other countries. We estimate models for three taxonomic groups, and find that while individual countries value conservation within their borders, in poor countries this effect is dominated by the negative impact of income growth. International concessional financial contributions to conservation in poor countries are found to be statistically insignificant. We conclude that countries care about the biodiversity within their national borders, but only when development priorities permit, and only when it becomes scarce enough that its value grows more rapidly than the return on alternative assets. There is little evidence that high income countries yet care sufficiently about biodiversity in the places where it is most threatened to affect conservation outcomes there.  相似文献   

10.
An integrated economic/ecological model is built to address tradeoffs between biodiversity conservation and two marketable rangeland ecosystem services: cattle grazing and elk hunting. The ecology is represented by an eleven species food web in which individual optimizing plants and animals engage in competitive and predator/prey relationships. The ecological model defines a steady-state set of sustainable grazing and hunting options, and for each option, biodiversity is measured using an index defined over the eleven species. In linking the ecology to the economics, social welfare depends on grazing profits and hunter net benefits. The problem can be stated as maximizing economic welfare over two ecosystem services, subject to their sustainable use and subject to a target level of biodiversity. A numerical application with economic and biological data from the Western United States is used to determine sustainable grazing and hunting options for alternative biodiversity levels, and to select the option that maximizes welfare.  相似文献   

11.
In this paper we investigate effects of overlap in species between ecosystems along a linear gradient on the location of marine protected areas (MPAs) under full cooperation, strategic behavior and conservation autarky. Compared to the full cooperation outcome, both strategic behavior and conservation autarky lead to under-investment in biodiversity protection. Under strategic behavior, however, we observe the additional problem of ??location leakage?? i.e. countries invest less in species protected by others. Conservation autarky eliminates location leakage; in ecosystems with partly overlapping species compositions at country borders it even induces MPAs that are too large from a global perspective. We also find that, in our setting of a linear gradient without migrating species, countries focus their conservation efforts on species unique to their own country and that these species are relatively well protected compared to common species.  相似文献   

12.
Many conservationists contend that economic growth and biodiversity conservation are incompatible goals. Some economists contest this viewpoint, arguing that wealthier countries have the luxury of investing more heavily in efforts to conserve biodiversity. Under this assumption, we expect a U-shaped relationship between per capita wealth and proportion of species conserved. We test this environmental Kuznets curve (EKC) using estimates of per capita income and deforestation rates (index of biodiversity threat) for 35 tropical countries. A prior analysis [Dietz, S., Adger, W.N., 2003. Economic growth, biodiversity loss and conservation effort. Journal of Environmental Management, 68:23-35] using conventional regression techniques failed to provide any support for the parabolic relationship predicted by the EKC hypothesis. Here, we introduce the use of quantile regression and spatial filtering to reanalyze this data, addressing issues of heteroskedasticity and spatial autocorrelation. We note that preliminary analysis using these methods provides some initial evidence for an EKC. However, a series of panel analyses with country-specific dummy variables eliminated or even reversed much of this support. A closer examination of conservation practices and environmental indicators within the countries, particularly those countries that drove our initial support, suggests that wealth is not a reliable indicator of improved conservation practice. Our findings indicate that an EKC for biodiversity is overly simplistic and further exploration is required to fully understand the mechanisms by which income affects biodiversity.  相似文献   

13.
This paper presents modeling approaches for wildlife and species conservation with a special emphasis on large mammals in a developing country setting. In such countries there are frequently conflicts over land use and species conservation, and institutions for managing conflicts are often weak or even lacking. In addition, most of the world species and biodiversity are found in developing countries. Two main issues are discussed. First, we study a situation where the wildlife is valuable, but is considered a pest by the local people living close to the wildlife. Second, we consider models with a discrepancy between management geography and biological geography, and where the species flows between a conservation area with no harvesting and a neighboring area with harvesting and possible habitat degradation.  相似文献   

14.
Biodiversity is an essential resource, which we classify as conditionally-renewable. In order to achieve conservation and sustainable use of biodiversity virtually all nation states signed the United Nations Convention on Biological Diversity. In this paper we investigate how the heterogeneity of countries in regard to ecosystems and wealth influences the stability of international biodiversity conservation agreements both without and with transfers. We further examine the effect of different degrees of ecosystem substitutability. We model a coalition formation game with players that have a continuous conservation choice. The conservation benefit is dependent on wealth and ecosystem quality. Aggregation of global benefits respects differences in ecosystem substitutability. In case of transfers, a fund redistributes coalition benefits according to a sharing rule. The main finding is that in the absence of transfers, compared to the homogeneous situation, heterogeneity in ecosystems and wealth reduces the size of a stable coalition. The destabilising effect is stronger the higher the ecosystem substitutability. Optimal transfers facilitate a large stable coalition.  相似文献   

15.
Habitat loss is a primary cause of loss of biodiversity but conserving habitat for species presents challenges. Land parcels differ in their ability to produce returns for landowners and landowners may have private information about the value of the land to them. Land parcels also differ in the type and quality of habitat and the spatial pattern of land use across multiple landowners is important for determining the conservation value of parcels. This paper analyzes the relative efficiency of simple voluntary incentive-based policies in achieving biodiversity conservation objectives. This topic is important not just for biodiversity conservation but for any effort to provide a public good requiring coordination across multiple decision-makers who have some degree of private information. We develop a method that integrates spatially explicit data, an econometric model of private land-use decisions, landscape simulations, a biological model of biodiversity as a function of landscape pattern, and an algorithm that estimates the set of efficient solutions. These methods allow us to simulate landowner responses to policies, measure the consequences of these decisions for biodiversity conservation, and compare these outcomes to efficient outcomes to show the relative efficiency of various policy approaches. We find substantial differences in biodiversity conservation scores generated by simple voluntary incentive-based policies and efficient solutions. The performance of incentive-based policies is particularly poor at low levels of the conservation budget where spatial fragmentation of conserved parcels is a large concern. Performance can be improved by encouraging agglomeration of conserved habitat and by incorporating basic biological information, such as that on rare habitats, into the selection criteria.  相似文献   

16.
This paper assesses the role of Biotechnology Development Agreements (BDAs) in creating incentives to conserve biodiversity. A major cause of species loss is the conversion of tropical forests to crop and pasture land. Biodiversity conservation, therefore, fundamentally depends on the economics of agricultural land use in developing countries. BDAs can play only a limited role in a comprehensive strategy to increase incentives for biodiversity conservation. Policymakers must examine biodiversity policies in the broader context of land tenure, rural poverty, and agricultural development in tropical countries .  相似文献   

17.
Coptis chinensis is a medicinal herb used in traditional Chinese medicine.This research features a case study in Shizhu County,China.Participatory Rural Appraisal(PRA) is used as the main tool for data collection.The study demonstrates that the current method of Coptis planting leads to forest destruction.Even with reforestation measures,it leads to the loss of biodiversity in the forest.It also shows that farmers cannot get satisfactory economic returns from Coptis planting,as the return is unstable and unpredictable.One alternative to the current Coptis planting mode is to incorporate it into the agroforestry system.Water shield planting also serves as a good alternative to Coptis planting itself.Improved methods of management,post-harvest processing,and marketing of Coptis are also proposed and analyzed.The intended contribution of this paper to the theoretical debate of sustainability shall be the provision of an example showing how agricultural production affects forest conservation.It also presents redressable measures to the negative consequences.Besides,one alternative livelihood pathway for the rural community in this case study is suggested.  相似文献   

18.
This paper is concerned with the empirical relationship between biodiversity conservation values and income. We use random effects panel models to examine the effects of income, and then GDP per capita, on willingness to pay for habitat and biodiversity conservation. In a meta-analysis, 145 Willingness To Pay estimates for biodiversity conservation where existence value plays a major role were collected from 46 contingent valuation studies across six continents. Other effects included in the meta-analysis were the study year; habitat type; continent; scope as presented to respondents; whether WTP bids were for preventing a deterioration or gaining an improvement in conservation, whether a specific species or specific habitat was protected; whether the questionnaire used a dichotomous choice or an open-ended format; distribution format; and the choice of payment vehicle. GDP per capita seemed to perform as well as an explanatory variable as respondent’s mean stated income, indicating that it is wealth in society as a whole which determines variations in WTP. Even if large variation, our main conclusion is, that the demand for biodiversity conservation rises with a nation’s wealth, but the income elasticity of willingness to pay is less than one.  相似文献   

19.
Biological diversity is a central component of the stock of natural capital on which all economic development is based. Other things being equal, loss of biologically diversity implies loss of development potential, and its conservation through sustainable use or outright protection implies the protection of that potential. One characteristics of biodiversity loss of especial importance is that biodiversity loss, more than any other current environmental problem, is associated with ecological threshold effects. The paper explores the implication of this characteristics for the properties of a biodiversity conservation strategy.  相似文献   

20.
Tradable permits are a common environmental policy instrument that has recently been applied also to the conservation of biodiversity. Biodiversity conservation differs in many respects to the classical applications of tradable permits like emissions control. One particularity is that, even if the permit system maintains a constant total amount of species habitat, habitat turnover (the destruction of a habitat and restoration elsewhere) affects the ecosystem. Another particularity is that the restoration of habitats often takes much time, leading to time lags between the initiation of restoration activities and the time when restored habitat is available for trading. We use an agent-based model of a tradable permit market to study the influence of heterogeneous and dynamic conservation costs and habitat restoration time lags on key variables of the market, such as the costs incurred to the market participants and the amount of habitat turnover. Our results show that there may be trade-offs between these key variables. We also find that restoration time lags can lead to fluctuations in permit prices that reduce the efficiency of the permit market. We conclude that temporal lags deserve a careful analysis when implementing tradable permit systems for the preservation of natural habitats and biodiversity.  相似文献   

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