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1.
对野生动物非法交易案件进行信息特征分析,可以把握案件的发生规律,提供决策者参考,以便有针对性预防和打击犯罪,更好地保护野生动物资源。本研究应用大数据分析的方法,对野生动物非法交易犯罪案件的文本数据进行结构化处理,建立了word2vec模型。从犯罪因素的角度统计分析了本类案件的信息特征,包括侵害人的特征、作案行为特征、侵害的动物或动物制品、侵害的时间和案件发生的地点等。在梳理基本特征的基础上应用关联算法构建了关联规则。根据特征分析和关联规则,提出了开展季节性防控、对特定群体和场所进行有针对性预防、对上游下游犯罪进行联动打击、与网管等多部门合作,运用现代科技成果进行打击和防范的对策建议。 相似文献
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通过对2000年、2002年野生动植物进出口贸易额的比对分析,对野生动植物进出口贸易中有关贸易额、贸易价格、中医药、海关记录数据等主要问题进行了具体分析,并对加强野生动植物的进出口管理提出几点建议:规范海关记录、监管标准;加强大宗贸易的审查和管理;推广限额、限价管理;进行全国野生动植物贸易调查;争取某些产品的特惠税制度等。 相似文献
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凤凰山自然保护区动植物资源与发展前景 总被引:4,自引:1,他引:3
辽宁省凤凰山自然保护区位于辽宁省凤城市东南,主要任务是保护和繁殖珍贵稀有物种。区划面积2600hm^2。区内既有长白区系代表植物,也有华北区系代表植物。有高等植物114科461属1028种,其中国家级保护植物10余种,省级保护植物13种。辽宁省新记录种7种。有脊椎动物24目59科162种。凤凰山风景奇秀,古迹众多,是辽宁省著名的旅游胜地,目前该区已建立生态型鸟园,放养丹顶鹤毛病稀鸟类40余种近千只 相似文献
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One hundred and fifty-four jarrah (Eucalyptus marginata) and 85 marri (Corymbia calophylla) trees were measured and assessed, and the numbers and sizes of hollows in these trees were determined by destructive sampling; 665 hollows were located and measured. The relationship between tree diameter and tree age was determined from counts of annual growth rings on 162 of these trees. Large trees and trees with moderately senescent crowns individually bear the most hollows. Although the number of hollows found in individual trees increased with tree diameter, the distribution of tree diameters in the forest is skewed and the large number of small trees with diameters between 40 and 80 cm contribute approximately 50% of all hollows in the jarrah forest. The distributions of entry size, and of hollow depth, are highly skewed, with small hollows occurring more frequently than large hollows. Although jarrah trees bear more hollows than marri trees and the distribution of entry sizes is similar for both tree species, the hollows in jarrah are significantly smaller than the hollows in marri. Most hollows are cylindrical in shape, vertically oriented and occur in dead wood in the tree crown. Relatively few hollows (14%) occur in the tree bole or at crown break. Counts of hollows made from ground level are inaccurate as estimates of the actual number of hollows in trees. 相似文献
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PeterF.Ffolliott 《林业研究》1997,8(2):108-110
IntroductionEcoledcalrelahonshipsanddePendenceofwildlifesPe-ciesonsouthwesternPOnderosapine(Pineponderosa)fOrestsarecloselyrelat6dtohabitatuse.Foraginghabits,seasOndfoodPreferences,anduseoftreesforfeedingarelawtydePendentuponthestrUctureandspahalar-rangme… 相似文献
8.
Curtis L. VanderSchaaf James A. Moore James L. Kingery 《Forest Ecology and Management》2004,190(2-3):201-218
This study looked at the effects that multi-nutrient fertilization had on understory vegetation nutrient concentrations at four conifer forested locations in the inland Northwest. Multi-nutrient fertilization of conifer stands cannot only enhance the overstory species in the inland Northwest but also the understory vegetation. Determination of nutrient concentration response to fertilization treatments can provide managers the ability to better manipulate their forests for grazing and wildlife habitat. We grouped the understory vegetation into three general life forms: forbs, grasses and grass-likes, and shrubs. Multi-nutrient fertilization had little effect on nitrogen concentration across all life forms. Potassium and sulfur generally increased in concentration. Micronutrients as a whole showed less variability in response to multi-nutrient fertilization. Boron, copper, molybdenum, and zinc generally showed increases in concentrations across all life forms. We were able to conduct analyses on a selected number of understory vegetation species. Individual species showed variability in nutrient concentration response to multi-nutrient fertilization. Wildlife habitat and grazing quality were both increased and decreased following multi-nutrient fertilization. Increases in nutrient concentrations will provide more nutritious vegetation to these animals and vice versa for decreases in concentrations. 相似文献
9.
Tim E. Carpenter Victor L. Coggins Clinton McCarthy Chans S. O’Brien Joshua M. O’Brien Timothy J. Schommer 《Preventive veterinary medicine》2014
Bighorn sheep currently occupy just 30% of their historic distribution, and persist in populations less than 5% as abundant overall as their early 19th century counterparts. Present-day recovery of bighorn sheep populations is in large part limited by periodic outbreaks of respiratory disease, which can be transmitted to bighorn sheep via contact with domestic sheep grazing in their vicinity. In order to assess the viability of bighorn sheep populations on the Payette National Forest (PNF) under several alternative proposals for domestic sheep grazing, we developed a series of interlinked models. Using telemetry and habitat data, we characterized herd home ranges and foray movements of bighorn sheep from their home ranges. Combining foray model movement estimates with known domestic sheep grazing areas (allotments), a Risk of Contact Model estimated bighorn sheep contact rates with domestic sheep allotments. Finally, we used demographic and epidemiologic data to construct population and disease transmission models (Disease Model), which we used to estimate bighorn sheep persistence under each alternative grazing scenario. Depending on the probability of disease transmission following interspecies contact, extirpation probabilities for the seven bighorn sheep herds examined here ranged from 20% to 100%. The Disease Model allowed us to assess the probabilities that varied domestic sheep management scenarios would support persistent populations of free-ranging bighorn sheep. 相似文献
10.
L. Del Río L. Chitimia A. Cubas I. Victoriano P. De la Rúa X. Gerrikagoitia M. Barral C.I. Muñoz-García E. Goyena D. García-Martínez R. Fisa C. Riera L. Murcia M. Segovia E. Berriatua 《Preventive veterinary medicine》2014
Leishmania spp. infection was investigated in tissue samples of wild carnivores from the Spanish Basque Country (BC), by PCR and DNA sequencing. The region is at the northern periphery of Leishmania infantum endemic Iberian Peninsula and infection in the dog (reservoir) or other species has not been previously reported. Leishmania kinetoplast DNA was detected by real-time PCR (rtPCR) in 28% (44/156) of animals. Specifically, in 26% of Eurasian badgers (n = 53), 29% of foxes (n = 48), 29% of stone martens (n = 21) and in 25–50% of less numerous species including genets, wild cats, pole cats, European mink and weasels. Infected animals particularly badgers, were most prevalent in the southernmost province of the BC (Araba) in areas dominated by arable land. Subsequent amplification and sequencing of a fragment of the rRNA internal transcribed spacer 2 (ITS2) from a subset of rtPCR positives samples confirmed the species as L. infantum, showing a high sequence homogeneity with ITS2 sequences of L. infantum from dogs and humans from southern Spain. In summary, this study reports for the first time L. infantum infection in wild carnivores from the BC including in stone martens, pole cats and minks in which infection has not been previously described. It supports the need to study infection in dogs and people in this region and is an example of the value of infection surveillance in wildlife to assess potential risks in the domestic environment and their role in spreading infections in non-endemic areas. 相似文献