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1.
This study investigates whether major USDA reports still provide important news to changing crop markets. The news component of each report, or market “surprise,” is measured as a difference between the USDA estimate and its private expectation in corn, soybeans, and wheat markets. Changes in the relevance of USDA information are assessed by examining changes in the magnitude of market surprises and shifts in the futures price reaction to these surprises, which isolates the impact of each report. The stable size of market surprises over time suggests that competition from alternative data sources has not reduced the news component of USDA crop reports. Increasing price reaction to most reports, including those facing competition from alternative information sources, suggests that value of public information may be enhanced in uncertain markets affected by structural changes.  相似文献   
2.
The mitigation hierarchy (MH) is a prominent tool to help businesses achieve no net loss or net gain outcomes for biodiversity. Technological innovations offer benefits for business biodiversity management, yet the range and continued evolution of technologies creates a complex landscape that can be difficult to navigate. Using literature review, online surveys, and semi-structured interviews, we assess technologies that can improve application of the MH. We identify six categories (mobile survey, fixed survey, remote sensing, blockchain, data analysis, and enabling technologies) with high feasibility and/or relevance to (i) aid direct implementation of mitigation measures and (ii) enhance biodiversity surveys and monitoring, which feed into the design of interventions including avoidance and minimization measures. At the interface between development and biodiversity impacts, opportunities lie in businesses investing in technologies, capitalizing on synergies between technology groups, collaborating with conservation organizations to enhance institutional capacity, and developing practical solutions suited for widespread use.  相似文献   
3.
Protected areas are key to the conservation of global biodiversity and ecosystem services; however, their success is contingent upon adequate funding. One possibility to increase funding for park management is to “sell” a wider suite of ecosystem services “produced” by protected areas, such as carbon sequestration. We conducted 420 tourist surveys to analyze willingness to pay (WTP) for ecosystem service benefits via a conservation fee in the Tambopata National Reserve in Peru. We also interviewed eight tour operators about their perceptions of the proposed fee. The average stated WTP was 15 USD. Sixty-six percent of tourists stated they would pay 10 USD or more, which, if actually paid, would have resulted in 318,000 USD for park management in 2015. Most respondents stated they would pay an additional fee if it supported biodiversity conservation or local ecosystem services, such as water, but less than 10% of tourists were motivated by carbon sequestration as a reason to pay the fee. Most tour operators supported the additional fee. Our findings suggest that tourists are willing to pay higher fees to support conservation but that interest in paying for additional ecosystem services from parks may not extend to global and intangible benefits such as carbon sequestration.  相似文献   
4.
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   
5.
We examine how board gender diversity is associated with biodiversity disclosures of a firm, and whether the Global Reporting Initiative (GRI) and the EU biodiversity strategy reinforce this relationship. Using institutional theory and resource dependency theory, our sample comprises 4013 firm-year observations from European corporations covering data from 2002 to 2016. We use panel regressions with country, time and industry dummy variables to analyse the disclosure of biodiversity initiatives (DBI) and logit regressions to explain biodiversity impact assessment (BIA). We find that board gender diversity is positively associated with the DBI and BIA of a firm, and that the GRI framework and the EU biodiversity strategy positively moderate this relationship. Moreover, the GRI framework and the EU strategic plan show positive relationship with the DBI, rather than BIA. Altogether, our evidence suggests that corporate boards with a higher proportion of female directors are more sensitive to the concerns of institutional pressures and respond to those concerns by increasing corporate biodiversity disclosures. Overall, we find that firms tend to comply with the GRI framework and the EU 2020 strategy by undertaking symbolic biodiversity disclosures, rather than providing a comprehensive disclosure of their impacts on biodiversity.  相似文献   
6.
中国蝶类生物多样性生存现状及其新的保护模式探索   总被引:1,自引:0,他引:1  
中国地跨古北区和东洋区,蝴蝶生物多样性非常丰富。蝴蝶具有巨大的美学、经济和生态价值。但是由于生态环境的破坏和市场利益的驱动,使我国蝴蝶生物多样性资源遭受了严重破坏。指出了我国蝴蝶生物多样性资源所面临的主要威胁以及所采取的保护措施,提出了蝴蝶生物多样性资源保护和可持续利用双赢的新思路,以期达到蝴蝶资源保护和可持续利用的良性互动。  相似文献   
7.
中国—东盟自由贸易区内生物遗传资源丰富,但随着区域内经济的发展,生物多样性遭到了威胁,为此双方酝酿建设中国—东盟生物多样性廊道。当前廊道内遗传资源面临盗掘滥用、外来生物入侵、孤立保护、利益归属不清晰等问题。必须把廊道内遗传资源保护同知识产权制度结合起来,加强跨国遗传资源的知识产权保护合作,完善廊道内各国遗传资源的立法和管理体制,并加快廊道内遗传资源的普查、登记、注册等基础工作。  相似文献   
8.
A number of problems in agricultural economics involve modeling joint distributions for which the assumption of multivariate normality may not be warranted. Yet, very little work has been conducted evaluating competing methods for modeling joint dependence. We develop a simulation framework to evaluate the bias and efficiency impacts of copula choice in the context of evaluating county‐to‐farm basis risk. The results suggest significant differences in performance across various copulas and approaches. The findings have important implications for risk analysis, insurance, and policy modeling problems in agriculture regarding the selection of method to model dependence among random variables.  相似文献   
9.
The rapid urbanization in developing countries implies an increasing pressure on urban agriculture for production. As most perishable food products come from this agriculture in close proximity to population concentrations, we analysed from an agronomic point of view how market-garden farmers can meet this increasing urban demand. This work took place in the case of Mahajanga, a secondary city with high increasing demographic rate on the Northwest coast of Madagascar. Based on preliminary surveys to characterize the farming systems (on a sample of 91 farms), 11 market-garden farmers chosen in the three main agricultural zones of the urban area were surveyed during two years. Surveys aimed at understanding their decision rules in crop choices, crop allocation to land and resource management, and to estimate their room for manoeuvre to increase their leafy vegetable areas under cultivation. The wholesalers and retailers who buy the farmers’ produce were also surveyed. A previous model of decision rules regarding crop location on farm territory was used to analyse the on-farm surveys and cartographic methods (GIS and on-farm manual representations) were used to quantify the land use. We highlight the following major points. (1) The leafy vegetable production in the surveyed farms already intensively uses land: farmers have complex decision rules largely depending on the water dynamics in the two main environments (lowlands and lakesides) where leafy vegetables are cultivated during the dry season. (2) The scarcity of farmers’ resources (labour money and water) leads to very little internal room for manoeuvre to increase the leafy vegetable production in the farms. (3) At territorial level however, some land reserve exist in one of the lowlands, but not on lakesides. The water availability for agriculture must be better informed through specialized hydrologic studies, as one of the main constraints nowadays to extend the agricultural area. An extrapolation to other cases of urban agriculture is then discussed as well as the role of agronomy to help urban planners to consider the place of agriculture in the urban development.  相似文献   
10.
The tidal river management (TRM) approach is an indigenous management practice in the Southwest part of the Ganges-Brahmaputra delta in Bangladesh. This approach has a high potential for extending area under agriculture with a positive impact on sustainable production and consequently on sustainable land use planning. Until recently, no studies provide a quantitative assessment on agricultural benefits of TRM operation. In this study, we aim to assess the benefits of TRM operation by using innovative approaches such as comparing land use change, agricultural production and economic cost-benefit analysis for two scenarios (with and without TRM) in the Hari-Teka-Bhadra catchment. We found that the financial benefit of TRM operation was 85.5 million US dollar per year from the agriculture sector. The results are useful for promoting land use policy through TRM approach in achieving greater sustainability in the area.  相似文献   
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