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91.
This paper analyses the cut flower market as an example of an invasion pathway along which species of non-indigenous plant pests can travel to reach new areas. The paper examines the probability of pest detection by assessing information on pest detection and detection effort associated with the import of cut flowers. We test the link between the probability of plant pest arrivals, as a precursor to potential invasion, and volume of traded flowers using count data regression models. The analysis is applied to the UK import of specific genera of cut flowers from Kenya between 1996 and 2004.There is a link between pest detection and the Genus of cut flower imported. Hence, pest detection efforts should focus on identifying and targeting those imported plants with a high risk of carrying pest species. For most of the plants studied, efforts allocated to inspection have a significant influence on the probability of pest detection. However, by better targeting inspection efforts, it is shown that plant inspection effort could be reduced without increasing the risk of pest entry. Similarly, for most of the plants analysed, an increase in volume traded will not necessarily lead to an increase in the number of pests entering the UK. For some species, such as Carthamus and Veronica, the volume of flowers traded has a significant and positive impact on the likelihood of pest detection. We conclude that analysis at the rank of plant Genus is important both to understand the effectiveness of plant pest detection efforts and consequently to manage the risk of introduction of non-indigenous species.  相似文献   
92.
Providing insight on decisions to hunt and trade bushmeat can facilitate improved management interventions that typically include enforcement, alternative employment, and donation of livestock. Conservation interventions to regulate bushmeat hunting and trade have hitherto been based on assumptions of utility- (i.e., personal benefits) maximizing behavior, which influences the types of incentives designed. However, if individuals instead strive to minimize regret, interventions may be misguided. We tested support for 3 hypotheses regarding decision rules through a choice experiment in Tanzania. We estimated models based on the assumptions of random utility maximization (RUM) and pure random regret maximization (P-RRM) and combinations thereof. One of these models had an attribute-specific decision rule and another had a class-specific decision rule. The RUM model outperformed the P-RRM model, but the attribute-specific model performed better. Allowing respondents with different decision rules and preference heterogeneity within each decision rule in a class-specific model performed best, revealing that 55% of the sample used a P-RRM decision rule. Individuals using a P-RRM decision rule responded less to enforcement, salary, and livestock donation than did individuals using the RUM decision rule. Hence, 3 common strategies, enforcement, alternative income-generating activities, and providing livestock as a substitute protein, are likely less effective in changing the behavior of more than half of respondents. Only salary elicited a large (i.e. elastic) response, and only for one RUM class. Policies to regulate the bushmeat trade based solely on the assumption of individuals maximizing utility, may fail for a significant proportion of the sample. Despite the superior performance of models that allow both RUM and P-RRM decision rules there are drawbacks that must be considered before use in the Global South, where very little is known about the social–psychology of decision making.  相似文献   
93.
张弢 《新疆环境保护》2009,31(2):40-42,46
按照生物学的分类,华南虎已经至少是极危等级了,几十年未观察到野生个体的存在,在这样的情况下,有一个个体存在和没有存在几乎没有什么区别了,因为,种群繁衍的基本个体基数已经不存在了,继续下去的结局就是近亲繁殖,种群快速退化,这样的结局也许令人难以接受,但是也许在漫长的一段时间之后,华南虎依然难逃灭绝的命运。野外华南虎已经绝迹,而圈养华南虎近交系数过高,种群面临严重衰退。  相似文献   
94.
Despite widespread recognition of the major threat to tropical forest biological diversity and local food security posed by unsustainable bushmeat hunting, virtually no long‐term studies tracking the socioecological dynamics of hunting systems have been conducted. We interviewed local hunters and collected detailed hunting data to investigate changes in offtake and hunter characteristics over 10 years (2001–2010) in Dibouka and Kouagna villages, central Gabon, in the context of hunter recollections of longer term trends since the 1950s. To control for changes in hunter behavior, such as trap location and characteristics, we report hunting offtake data per trap. Our results suggest the hunting area was already highly depleted by 2001; local hunters reported that 16 large‐bodied prey species had become rare or locally extirpated over the last 60 years. Overall, we observed no significant declines in hunting offtake or changes in species composition from 2001 to 2010, and offtakes per trap increased slightly between 2004 and 2010. However, trapping distance from the villages increased, and there was a switch in hunting techniques; a larger proportion of the catch was hunted with guns in 2010. The number of hunters declined by 20% from 2004 to 2010, and male livelihood activities shifted away from hunting. Hunters with the lowest hunting incomes in 2004 were more likely than successful hunters to have moved away from the village by 2010 (often in response to alternative employment opportunities). Therefore, changes in trap success (potentially related to biological factors) were interacting with system‐level changes in hunter number and composition (related to external socioeconomic factors) to produce a relatively static overall offtake. Our results highlight the importance of understanding the small‐scale context of hunting to correctly interpret changes or apparent stasis in hunting effort and offtake over time. Cambio Social y Ecológico a lo Largo de Una Década en un Sistema de Cacería Aldeana, Gabón Central  相似文献   
95.
峨眉山野生观赏蕨类资源及其开发利用   总被引:2,自引:0,他引:2  
峨眉山野生蕨类植物资源十分丰富,有540余种,其中具有较高观赏价值的有104种,分别隶属于36科60属。对峨眉山的野生观赏蕨类植物资源的生长类型、观赏价值及其分布作了介绍,并对峨眉山观赏蕨类资源的开发利用提出了建议。  相似文献   
96.
对安徽野生祁术的特点、开发条件、存在问题进行了分析和论述.通过与白术比较,显示出野生祁术的药用价值和经济价值高,具有一定的食用价值(其总糖、Arg和钙含量较高).提出了安徽野生祁术开发的基本对策:强化资源保护和基础技术研究;加大资金投入和人工驯化栽培力度;不断满足市场及旅游经济的需求.  相似文献   
97.
雅鲁藏布江大拐弯地区野果类资源初探   总被引:2,自引:1,他引:2  
本文通过对雅鲁藏布江大拐弯地区的考察.基本摸清了该地区野生果类资源的种类及分布状况,发现了1000年树龄的野生果树.以及可供科研和开发利甲的种质资源.同时.从考古资料的研究和考察中发现西藏是多种果肉的原产地,也是天然的果树种质资源库.  相似文献   
98.
ABSTRACT: The lower 4 miles of the Red River, a tributary of the Rio Grande in northern New Mexico, was designated as one of the “instant” components of the National Wild and Scenic River System in 1968. The Bureau of Land Management (BLM), as the managing agency of the wild and scenic river, was a participant in a general water rights adjudication of the Red River stream system. The BLM sought a federal reserved water right and asserted a claim to the instream flows necessary to protect and maintain the values of the river. Instream flows are not recognized under New Mexico water law. Instream flow requirements were determined by several methods to quantify the claims made by the United States for a federal reserved water right under the Wild and Scenic Rivers Act. The scenic (aesthetic), recreational, and fish and wildlife values are the purposes for which instream flow requirements were claimed. Since water quality is related to these values, instream flows for waste transport and protection of water quality were also included in the claim. The U.S. Fish and Wildlife Service's Instream Flow Incremental Methodology was used to quantify the relationship between various flow regimes and fish habitat. Experience in this litigation indicates the importance of using state-of-the-art methodologies in quantifying instream flow claims. The incremental methodology held up well under technical and legal scrutiny and is an example of the latest methodology that was applied successfully in an adjudication. On February 23, 1984, the parties involved in the adjudication entered a precedential stipulation recognizing a federal reserved right to instream flows for the Red River component of the National Wild and Scenic River System.  相似文献   
99.
李宏立 《灾害学》1996,11(3):89-92
针对灾区医疗队生存和救治工作中存在的问题,提出了解决办法,包括吃、住、行及救治等方面。  相似文献   
100.
安徽省自然条件优越,野生动物资源丰富,但在资源的开发利用上存在不少问题。只有在科学研究的基础上,把资源的开发利用与保护有机地结合起来,才能实现野生动物资源的永续利用。  相似文献   
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