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21.
觅食是获取营养物质和能量的重要途经。对于栖息在四季分明地区的灵长类动物而言,低温以及食物资源相对匮乏的冬季是其生存和生长发育的瓶颈期。本研究以安徽黄山的野生藏酋猴(Macaca thibetana)天湖山群为对象,于2019年11月至2020年1月采用瞬时扫描取样法(Instantaneous scan sampling)采集猴群觅食行为数据,并分析其冬季食物组成及食物中各化学成分含量对取食的影响。结果显示,野生藏酋猴在冬季共取食23科31属34种植物,主要包括壳斗科(Fagaceae,21.62%)、樟科(Lauraceae,17.57%)、蔷薇科(Rosaceae,8.11%)的植物,取食部位以叶片(66.22%)和果实(种子)(24.32%)为主。不同取食部位的水分、总糖、淀粉、脂肪、单宁等成分存在显著差异。其中,叶片的水分含量高于果实(种子)、茎和芽,茎和果实(种子)含有较高的总糖,果实(种子)的淀粉和脂肪含量最高,芽的单宁含量最高。此外,取食植物中的总糖含量高于非取食植物。结果表明,野生藏酋猴适应寒冷冬季与食物匮乏的觅食策略是对植物种类、植物部位及其主要营养成分的综合结果。 相似文献
22.
我国是世界上植物多样性最丰富的国家之一, 1999年发布的《国家重点保护野生植物名录》(下称《名录》(第一批))明确了国家重点保护野生植物的范围, 为依法强化保护、规范无序开发利用、提高公众保护意识奠定了基础。20多年来, 我国野生植物多样性保护形势发生了很大变化, 需要对《名录》进行调整。2018年, 国家林业和草原局、农业农村部启动《名录》调整工作, 物种的遴选遵循了5条基本原则和4条补充性原则, 这些原则主要涉及中国珍稀濒危物种, 具有重要经济、文化、科研、生态等价值物种的入选以及部分物种的排除。经国务院批准, 2021年9月7日, 国家林业和草原局、农业农村部发布了调整后的《名录》, 包括真菌类、藻类、苔藓、石松类和蕨类植物、裸子植物和被子植物, 共计约1,101种(455种和40类)野生植物列入其中。本文简要介绍了《名录》调整的必要性、原则和程序及调整后的情况。 相似文献
23.
中国是全球生物多样性最丰富的国家之一。最近40年, 中国的植物多样性保护取得了巨大成就, 实施了多项政策和法律, 尤其是《野生植物保护条例》和《国家重点保护野生植物名录》先后颁布, 奠定了中国植物保护的法律和政策框架, 就地保护和迁地保护网络基本形成。但与生态文明建设的要求相比, 野生植物保护依然存在许多不足。本文系统回顾了中国野生植物保护管理的政策和法律制度, 从就地保护、迁地保护、开发利用活动管理三方面分析了其优缺点并提出建议; 重点对修订《野生植物保护条例》进行讨论并提出建议, 包括修订野生植物和人工培植的定义、优化对开发利用活动的管理程序、加强国际法和国内法的衔接、细化优化罚则等。 相似文献
24.
The role of state forests in the conservation of the savannah environment of western Burkina Faso (West Africa) was assessed
by considering the customary and fundamental biological components of plant diversity. The focus is on the “ordinary biodiversity”
which constitutes the current environment of human populations and which generates their resources. Overall floristic composition,
α, β, γ diversities and species accumulation curves of landscape units were compared inside and outside protected areas. Common species
were identified according to their frequencies in landscape units and their local abundance. The occurrences of functional
(life form, dispersion, etc.) and human-valued (current uses, potential threats, etc.) traits were compared. Current land
uses outside protected areas have an unequal effect on the various components of plant diversity. Species richnesses and specific
structures were all the more altered for woody species as agricultural pressure is high; conversely, they were maintained
for herbaceous communities for which the proportion of wide-ranging species increased. The preservation of useful plant species
on cultivated lands was obvious for woody species with edible fruits but less tangible for timber and service wood. It was
deficient for species that furnish other non-wood products (e.g. leaves used as food or fodder), the conservation of which
may be jeopardized where anthropic pressure is high. Given current land uses and dynamics, maintaining conservation areas
in land use planning is crucial in order to preserve ordinary biodiversity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
25.
Anne-Laure Brochet Michel Gauthier-Clerc Raphaël Mathevet Arnaud Béchet Jean-Yves Mondain-Monval Alain Tamisier 《Biodiversity and Conservation》2009,18(7):1879-1894
Many wild species, like waterbirds, are exploited for their economic interests. At present, the annual western Palearctic
duck bag is at least 17 million birds. From a sustainable management perspective, wetland users and managers request predictions
of spatial distribution and abundance variations of these bird populations. The objective of this study was to analyze local
factors potentially influencing the diurnal distribution and population size of wintering ducks and coots, the main game species,
in Camargue (southern France). First, we showed that marshland surface area, salinity and hunting disturbance were the principal
variables explaining the duck and coot distribution. Secondly, we tested the hypothesis that hunting disturbance would reduce
the carrying capacity of the Camargue with two analyses: the effect of creating a protected area and the change of the hunting
closing date. This hypothesis was not validated. Our study therefore led us to reconsider the research orientations on the
carrying capacity in this wetland. The surface of protected day roosts seems presently sufficient in the Rhone delta. Consequently,
to increase the population size with the same level of hunting disturbance at the scale of the Camargue, alternative strategies
should be envisaged, such as the creation of nature reserves on nocturnal feeding ground or the creation of large management
units with limited disturbance. 相似文献
26.
Gene flow from genetically modified rice to its wild relatives: Assessing potential ecological consequences 总被引:4,自引:0,他引:4
Pollen-mediated gene flow is the major pathway for transgene escape from GM rice to its wild relatives. Transgene escape to wild Oryza species having AA-genome will occur if GM rice is released to environments with these wild Oryza species. Transgenes may persist to and spread in wild populations after gene flow, resulting unwanted ecological consequences. For assessing the potential consequences caused by transgene escape, it is important to understand the actual gene flow frequencies from GM rice to wild relatives, transgene expression and inheritance in the wild relatives, as well as fitness changes that brought to wild relatives by the transgenes. This article reviews studies on transgene escape from rice to its wild relatives via gene flow and its ecological consequences. A framework for assessing potential ecological consequences caused by transgene escape from GM rice to its wild relatives is discussed based on studies of gene flow and fitness changes. 相似文献
27.
Ignacio García Sebastián Napp Jordi Casal Anselmo Perea Alberto Allepuz Anna Alba Alfonso Carbonero Antonio Arenas 《European Journal of Wildlife Research》2009,55(2):173-178
Serum samples from 210 wild ruminants collected between 2006 and 2007 in southern Spain were tested for antibodies against
bluetongue virus (BTV) by means of a competitive ELISA assay. Eighty-seven of the 210 wild ruminants analysed (41%) showed
antibodies against BTV. Statistically significant differences were found in the seroprevalence among species: 66% (65 of 98)
for red deer (Cervus elaphus), 50% (ten of 20) for fallow deer (Dama dama), 33% (three of nine) for mouflon (Ovis aries musimon) and 11% (nine of 83) for Spanish ibex (Capra pyrenaica). Overall, the sites where seropositive wild ruminants were found coincide with the areas where BTV had been detected in
livestock, but in eastern Sierra Morena, the virus circulated in wild ruminants, although it had not been detected in domestic
ruminants in the same areas. Wild ruminants over 1-year of age (sub-adults and adults) had significantly higher seroprevalences
than juvenile animals. Statistically significant differences were also observed between BTV seroprevalence and management
(free-ranging vs. captivity) with higher prevalence in free-ranging animals. The high seroprevalences obtained suggest that
BTV is widespread in wild ruminants in southern Spain. This factor could have an important influence on the evolution of the
infection in domestic livestock and indicates the need to include wild ruminant species in BTV surveillance or control programs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
28.
滇西北野生观赏花卉调查 总被引:5,自引:0,他引:5
依据野外调查结果和有关文献资料,运用统计和比较的方法,对滇西北地区野生花卉的多样性进行了研究。结果表明,滇西北野生花卉有83科324属2206种。其中草本花卉1,163种,木本花卉。743种,滇西北特有野生花卉751种,珍稀濒危花卉35种。本文对滇西北地区野生花卉植物的种类、分布、观赏类型、花色、花期、受威胁状况以及特有现象进行了详细地统计分析。发现滇西北地区花卉植物的丰富度依次为丽江、中甸、贡山、德钦、维西、鹤庆、福贡、洱源、大理、兰坪。从垂直分布上看,海拔2400~3000m以及海拔3500m以上的地段花卉植物较为丰富,且特有和珍稀濒危野生花卉植物也较多地集中在这两个地段。按花色紫蓝、橙黄、红、白四大类型分类,则以紫蓝花种类最为丰富(约400种)、橙黄花次之(约230种)、红花较少(约170种)、白花最少(约140种)。 相似文献
29.
野猪及其与家猪杂种猪Myostatin基因3''编码区的克隆和序列分析 总被引:8,自引:0,他引:8
Myostatin, which is a highly conservative gene among breeds, is a negative regulator of muscle. The 3' coding region of wild boar and crossbred pig myostatin was cloned by RT - PCR and sequenced. Compared with that of GenBank, the homology of the nucleotide sequence between wild bear and crossbred pig is identical in this region indicating that domestic pigs were evolved from wild boar and there was not changed in this region during the evolution processes. 相似文献
30.
野生稻种质资源描述规范和数据标准应用 总被引:6,自引:3,他引:3
陈成斌 《植物遗传资源学报》2006,7(3):257-259
论述了野生稻种质资源描述规范、数据标准和数据质量控制规范编制原则、适用范围及应用策略,对于促进全国野生稻种质资源的整合、规范鉴定评价,以及信息与实物共享机制与体系的建立,推动野生稻优异种质的研究与利用,变资源优势为经济优势都具有重要的现实意义。 相似文献