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51.
Human-driven land-use changes often cause a decline in biodiversity. Although traditional agricultural practices maintained biodiversity at high levels, recent land-use changes may have negative consequences on species composition. In this study, we examined the hypothesis that land consolidation, which is a major recent land-use change in agricultural areas, decreases plant species diversity over the long term (the so-called negative legacy). To test this hypothesis, we examined the relationships between consolidated areas and the occurrence of threatened plant species across Japan and at the prefecture scale. Twenty-three threatened plant species were selected, all of which were formerly common. Our results show that areas containing records of threatened plant species rarely experienced consolidation at whole-country and prefectural scales. Breakdown analysis showed that unconsolidated agricultural areas contained significantly more threatened species than consolidated agricultural areas. These results suggest that threatened plant species require unconsolidated agricultural areas (i.e., these species could not grow in consolidated areas). Thus, we propose that consolidation history could be used as an indicator of the potential for biodiversity recovery. We also suggest that consolidated agricultural areas should be used for food production rather than for the restoration of biodiversity, for reasons of cost efficiency.  相似文献   
52.
Most small-scale social economies are characterised by their deficiency, lack, and/or difficulty in matching natural data. Against this backdrop, this paper builds a relatively uniform theoretical framework and designs a more economical and objective method for demarcating ecological conservation redlines (ECR) based on sensitivity assessment of ecosystem services. The results show that the sensitivity assessment model designed in this study can identify sensitive zones effectively, and that the ECR in Hubei Province are well within the sensitive zones so identified. The delimited areas based on the sensitive assessment of ecosystem services have great similarities (95%) with the actual ECR areas in Hubei Province. The most ecologically important functional zones (EIFZ) can also be identified using the regional ecological sensitivity coefficient. When the threshold of EIFZ is set higher, the probability that it falls within the ecologically sensitive areas is greater and the ECR delimited by the method proposed in this study will be more reliable. Theoretically, the delimitation of ECR can be inserted at any evaluation level with a grid resolution higher than that of the land use data, which can be used as a supplement to the ECR delimitation method in ecology or geography.  相似文献   
53.
Conservation auctions for payment for ecosystem services (PES) are useful to identify the levels of incentives that will cover the opportunity costs of farmers supplying ecosystem services. Although auctions are increasingly used for allocation in PES schemes, the factors that lead to their successful implementation and eventual environmental outcomes are poorly understood in developing countries. We investigated the socio-economic and institutional contexts that led to smallholders' auction winning and eventual compliance using linear mixed-effects models, and post-auction and post-contract surveys. We employed a case study of a conservation contract preceded by a sealed-bid, multiple round, uniform price auction for watershed services from coffee farmers in Lampung, Indonesia. The auction participants presented low education levels, low asset endowments and small plot sizes. The study obtained evidence that farmers with larger plot areas were more likely to win the contracts, suggesting economies of scale. Most farmers considered the auction a fair self-selection mechanism to allocate contracts where allocation was not influenced by power or social rank. Non-compliance was associated with labor availability constraints, short duration of land ownership and existence of previous conservation applications, suggesting lax of capability to invest in applying conservation agriculture. Final bids were however not good predictors of compliance, among other factors, calling into question the potential of auctions to elicit the actual incentive from the farmers. Ensuring that farmers understand the purposes of auctions for effective contract allocation beyond a mere game and identifying farmers that might encounter difficulties fulfilling the contract could increase the likelihood that such a PES scheme would be successful.  相似文献   
54.
Land use and cover (LUC) change is a major driver of ecosystem service loss worldwide. In response, policymakers have designed conservation strategies that incentivize the establishment and maintenance of LUC types associated with higher ecosystem service provision. Many of these policies also aim to promote social and economic goals such as reducing poverty. Attempts to measure the impact of policy-driven LUC change on stakeholders typically focus only on economic outcomes for landowning participants or aggregate the socio-economic outcomes of diverse groups. In this study, we applied local ecological knowledge (LEK) held by beekeepers in Costa Rica to understand the impact of policy-driven LUC change on this specific group of often non-landowning stakeholders. Beekeeping is a globally important rural livelihood and provides pollination services to crops and wild plants. We synthesized beekeeper LEK using a mixed-methods approach including apiary mapping exercises (n = 215 apiaries), questionnaires (n = 50 participants), and follow-up interviews (n = 21 participants). Our study revealed that some policy-driven LUC changes have limited beekeepers’ access to preferred land uses, such as secondary and mature forests with native trees. Participants reported concern for their livelihoods due to policy-driven spatial and temporal change of floral resources via the establishment of tree plantations, changes in pasture management, and laws that prohibit beekeeping in national parks and reserves. Our study provides evidence of unintended outcomes from land use policies, including Payment for Ecosystem Services, with disproportionate negative impacts on non-landowning residents who depend on natural resources in the landscape for their livelihoods. Our study illustrates potential inequality rising from current incentive mechanisms associated with Payments for Ecosystem Services and other conservation policies and calls for policymakers to consider LUC change impacts on non-landowning stakeholders.  相似文献   
55.
Traditionally, sourcing decisions such as what to buy and from whom to buy it were viewed as clerical in nature. Today, however, many executives view sourcing decisions as strategic and these decisions are being made from more prominent positions within firms. Indeed, over time more companies are embracing the concept of strategic sourcing—making acquisition decisions with the intent of creating value and achieving a competitive advantage. In this article, we introduce the Special Topic Forum articles on strategic sourcing and performance. Each offers important implications for strategic sourcing research and practice. An overall implication is that some traditional supply chains appear to be giving way to supply ecosystems, which represent a set of interdependent and coordinated organizations that share common adaptive challenges and that collectively shape the creation and nurturing of a sourcing base that contributes to competitive advantage and superior performance. We offer several theoretical perspectives that hold promise for explaining supply ecosystem functioning and outcomes. In terms of practice, firms need to adapt their strategic sourcing to this evolution or run the risk of being weakened.  相似文献   
56.
孔海东  张培  刘兵 《技术经济》2019,35(6):99-108
通过文献调查并结合案例的描述性分析,提出数字技术时代价值网络中不同行为主体之间的赋能内涵、关键维度以及基于赋能跨层次效应的价值共创行为分析框架。将"赋能氛围""主体赋能"分别作为价值网络中赋能的宏观维度和微观维度进行概念化。界定了两个维度的关键组成要素,分别包括信息共享、开放性结构、协同规则以及主体关系、资源整合和影响。构建了赋能的跨层次效应模型,分析了赋能的宏观-微观跨层次效应及其对价值网络生态和主体价值创造的影响。  相似文献   
57.
Estuaries provide advantageous sites for both harbors and fish habitats. In many countries, harbor expansion in estuaries contributed to the decline of fish populations with impacts at the global scale. Restoring these habitats is important to prevent a global biodiversity crisis but is costly and potentially unaffordable for polluters under the Polluter Pays Principle. Such affordability issues prompt decision-makers to reduce environmental targets of restoration programs. Harbor infrastructures destroy fish habitats but generate benefits for society and contribute to the public interest, raising some questions on who is responsible for environmental degradations and who can afford environmental restoration costs? One way to allocate restoration costs is to analyze the amount of harbor services consumed by economic sectors. This paper addresses these questions by computing burden sharing scenarios with an input–output matrix. These scenarios are simulated under the shared responsibility principle to distribute restoration costs among stakeholders in the Seine estuary, France.  相似文献   
58.
Landscapes provide an array of services to society, from the provision of food and material, to the provision of cultural ecosystem services such as recreation, aesthetics or spirituality. Studies on cultural ecosystem services, however, remain rare and little is known about the spatial localisation of these services. In this study, we adopt and test a framework to identify and map the provision of cultural ecosystem services as perceived by tourists in an Alpine region, i.e. the region of South Tyrol in Italy. A photo-based questionnaire survey is combined with cartographical representations of landscape types to elicit hot and coldspot areas of cultural ecosystem service provision. We statistically test for influences of the land use type and the respondents' socio-demographic background on the tourists' perception of these services. The results show that different spatial patterns emerge for each of the investigated cultural ecosystem services depending on the distribution and extent of the landscape types to which they are related. In particular traditionally managed landscapes, small in extent and mainly scattered over large areas between 1000 and 2200 m a.s.l., are hotspot areas of aesthetic beauty, leisure activities and spirituality. In contrast, intensively managed landscapes, mainly located in the lowland plains of the study site, are considered to be more important for the provision of cultural heritage values. While the results suggest that land use type exerts the strongest influence upon tourists' perception, factors such as the respondents' perceived importance of the services, their gender, cultural background, environmental engagement and experience with the landscape play a significant but subordinate role. We conclude that the spatially explicit information about the provision of cultural ecosystem services can serve as a helpful basis for the design and further implementation of land use policies that acknowledge the high touristic value of traditionally used landscapes in mountain regions.  相似文献   
59.
This research looks at post‐2006‐war reconstruction of the southern suburbs of Beirut under the auspices of Hezbollah (the Islamic resistance movement in Lebanon). The project was widely acclaimed as an alternative to current neoliberal planning practices in the Middle East and beyond. Based on a critical reading of the conception of property issues in this planning project, the article argues that this reconstruction presents a new geometry or alternative to the mainstream configuration of neoliberal urbanism, rather than a departure from its precepts. The reason for this is that the adopted language of property corresponds closely with the conception of property advocated by neoliberal planning, one that enshrines private, individual ownership as sacred and desirable and that works to strengthen its model in the city. I further argue that the ‘neoliberal planning regime’ within which Hezbollah's urban intervention occurs is not accidental; rather, it is necessary for the party's control of this space's future and for consolidating its territory in the city. It is hence expected that Hezbollah's planning in the city will produce the same decried effects as neoliberal planning elsewhere in the city rather than usher an innovative, progressive model of planning.  相似文献   
60.
Many developing countries face a major challenge today: how to safeguard the biodiversity maintained in the fields of the rural poor - which constitute a national and global public good - whilst meeting those same people's development needs and rights? A solution to this dilemma has thus been sought in adapting the design and implementation of Payments for Ecosystem Services (PES) concepts to the conservation of agrobiodiversity.Here we review the application of nine such Payments for Agrobiodiversity Conservation (PACS) schemes that have been applied to date in four Latin American countries over the period 2010–2018. These covered 130 threatened varieties across a number of major food crops, and involved over 100 farming communities and 1,100 farmers (45 % of which were women). Conservation service offers were received through a competitive tender mechanism. Average bid offers revealed high heterogeneity, varying between US$675/ha. to ten times as much.In relation to issues identified as key to PES, such as spatial targeting, differentiated payments and conditionality, the underlying design of the PACS schemes may be considered solid. PACS-related prioritisation processes allow for the a priori identification of sites with high ecosystem service densities and high threat levels. The use of competitive tenders permits accounting for cost heterogeneity in the provision of conservation services and for payments to be differentiated. Conditionality is strong.In terms of implementation, a “back of the envelope” calculation based on the results of the competitive tenders suggests that conservation costs are modest. For a priority conservation portfolio of 100 varieties (which may be from different crops) each with a target area of five hectares, costs would amount to just under US$860,000 over twenty years or US$70,000 p.a. at a 5 % discount rate. The small-scale and one-off nature of the interventions realised to date, along with threatened crop variety seed availability constraints, have however meant that environmental effectiveness has been incomplete in the short-term (area cultivated with specific threatened varieties increased, but still below the “not at risk” threshold). The establishment of systematic monitoring systems is required to determine longer-term impacts and inform more regular PACS interventions within a dynamically evolving systems context.  相似文献   
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