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2010年12月至2011年2月,在新疆哈密山区,采用截线抽样法和遥感技术,对野生天山马鹿(Cervus elaphus songaricus)种群现状和冬季生境选择进行了研究。在不同区域和不同类型栖息地共布设了28条样线,样线总长度达60.1 km。其中,16条样线上发现马鹿共233头,调查区域平均种群密度(2.83±1.01)头/km2,种群数量(1 684.56±379.71)头,与1993年的调查结果相比有所上升。雌雄性比为2.24:1,幼体和亚成体总数多于成体和老体总数,种群数量呈增长趋势。根据野外考察GPS数据并解译天山马鹿分布生境2006秋季的LANDSAT TM/ETM+遥感影像,将生境要素分为山地针叶林、草甸、灌木丛、农田和戈壁5种类型,其中,草甸与山地针叶林为天山马鹿冬季适宜生境。  相似文献   
43.
吕慎金  杨燕  魏万红 《生态学报》2013,33(1):132-139
采用目标动物取样法(Focal Animal Sampling)对江苏省扬州市平山堂养殖场及扬州市动物园48只梅花鹿(Cervus nippon)的昼间行为进行观察,以Kappa阿片受体(Kappa Opoioid Receptor 1,OPRKl)为目的基因,采用单核苷酸多态性(Single Nucleotide Polymorphisms,SNPs)方法,利用引物P-5和P-9获得OPRK1基因的不同基因型,并将二者进行最小二乘均值的多重比较,以确定OPRK1基因SNP与梅花鹿昼间行为的相关性.结果表明,引物P-5各基因型间与修饰行为两两差异显著(P<0.05),其它行为EE型和FF型差异显著(P<0.05),而另外5种行为性状在各个基因型中没有检测到显著差异;引物P-9各基因型间卧息行为GG型和GH型个体行为之间存在极显著差异(P<0.01),观望行为GG型、HH型和GH型3种基因型个体两两之间差异显著(P<0.05),修饰行为HH型和另外两者差异显著(P<0.05).研究表明,OPRK1基因多态性和梅花鹿昼间行为性状存在一定相关.  相似文献   
44.
定量分析保护地内的人为干扰对珍稀濒危物种的保护非常重要。红外相机技术可为评估人为干扰提供重要数据。我们于2014年11月至2017年12月,利用红外相机对浙江清凉峰国家级自然保护区千倾塘区域的野生华南梅花鹿(Cervus nippon kopschi)栖息地存在的人为干扰进行了监测调查。共计布设57个监测位点,记录到人为干扰独立照片152张。识别到7个主要干扰类型,分别为行走干扰、盗采干扰、盗伐干扰、盗猎干扰、牛干扰、羊干扰、家犬干扰。研究结果表明,栖息地内的人为干扰与梅花鹿的活动节律和重要分布区域存在一定的重叠。人类干扰(包括行走、盗采、盗伐、盗猎)是主要干扰。干扰高发季节为春、秋季。行走干扰、采伐干扰、家犬干扰在上半年(1-6月)最高。牛干扰在4月和11月较高,羊干扰在4月和9月最高。保护区内干扰主要出现在07:00-18:00,干扰强度最高的时间段为08:00-10:00。从空间分布上,华南梅花鹿的主要分布小区(道场坪、癞痢尖、螺蛳尖)以及重要水源地(千倾塘)干扰强度较高。人类干扰和家犬干扰集中于千倾塘区域西部,放牧干扰集中于千倾塘区域东部。本次研究为利用红外相机进行保护区内人为干扰研究提供了案例,同时为管理部门制定和实施有效管理策略提供了科学依据。  相似文献   
45.
Conservation conflicts are often difficult to resolve due to a combination of poorly defined property rights, inadequate funding, high transaction costs, and contrasting value systems among stakeholders. This paper explores these barriers to collaboration in the context of the emerging deer crisis in the Scottish Highlands, where deer numbers are now higher than at any time in recorded history. In particular we explore the potential role of recreational hunting in the government’s strategy to contain rising deer numbers from the landowners’ perspective. Using both qualitative and quantitative analysis we find that hunting traditions and personal preferences, reinforced by antipathy to conservationists and their perceptions of land stewardship, are the major barriers to shooting more deer for conservation objectives. We conclude that an expansion of commercial hunting opportunities is the best practical approach to resolving the current conflict over deer, but conservationists and landowners must work together to create a more positive context for hunter-conservation initiatives and activities.
Douglas C. MacMillanEmail:
  相似文献   
46.
Deer overabundance reduces forest ground-layer vegetation and can cause cascading impacts on a forest ecosystem. To predict these effects, we must elucidate the relationship between deer density and the status of ground-layer vegetation. This relationship was studied in the Boso Peninsula, where the deer population density exhibits a clear geographical gradient. We examined species richness and cover of ground-layer vegetation at several cedar plantations and hardwood forests in the Boso Peninsula. We also examined whether deer impacts were altered by light condition, soil water content and forest type (cedar and hardwood). Species richness of ground-layer vegetation was maximized at an intermediate level of deer density, suggesting an intermediate disturbance effect. This phenomenon was compatible with the observation that evergreen species, which were competitive dominants, decreased with increasing deer density, whereas less competitive deciduous species increased until herbivory was intermediate. As deer density increased, cover of ground-layer vegetation gradually decreased, but species unpalatable to deer increased in abundance, suggesting indirect positive effects of deer for unpalatable species. Cedar plantations tended to have greater species richness and ground-layer cover than hardwood forests with similar deer levels. Canopy openness, an indicator of light conditions, increased species richness of hardwood forests and ground-layer cover of cedar plantations, even under deer herbivory. Topographic wetness index, an indicator of soil water content, significantly increased the ground-layer cover of cedar plantations under deer herbivory. These results emphasize the importance of environmental productivity and forest type in the management of ground-layer vegetation experiencing deer overabundance.  相似文献   
47.
To define the quantitative and qualitative effects of gossypol (GP) on deer (Cervus elaphus) semen, the animals were fed cottonseed (CS). Adult stags each received 350 g of CS for 109 days. Animals received 15 mg of gossypol per kilogram body weight per day. Quantitative and qualitative parameters of experimental ejaculates (n = 182) were compared to ejaculates (n = 571) of control animals (n = 5) collected during three previous natural reproductive seasons. Ejaculate fractions were evaluated by classical methods used in domestic animals. In this paper, we show that mature male deer fed CS exhibited morphological changes and decreased motility of spermatozoa and abnormalities in spermatogenesis. Radioimmunoassay measured concentrations of various steroid hormones (T-testosterone, A4-androstenedione, and E2-estradiol 17β) in separated ejaculate fractions of the CS group were compared to a control group of stags. Generally, mean steroid concentrations in CS-treated deer decreased during the entire sampling period in examined ejaculate fractions. These changes resulted in decreased semen quality with no detectable side effects in the animals. It seems that gossypol fed to the deer in the form of CS serves as an efficient male contraceptive.  相似文献   
48.
Using a generalized linear mixed model approach, we determined the most important risk factors affecting the probability of damage by sika deer in a forest plantation in Japan. Candidate risk factors included tree species, stand age, peripheral dwarf bamboo community, topographical factors, snow depth, and human disturbance factors. Based on this model, we developed a risk map of forest damage. The model indicated that the most important risk factor was stand age, followed by tree species and maximum snow depth. Our predictive model has practical use due to its high classification accuracy (83.9%). To decrease damage from sika deer, an afforestation plan that incorporates these factors should be implemented. Because it is based on common, forest GIS data that have recently been compiled by several local governments in Japan, our modeling method of deer damage can easily be adapted to other areas.  相似文献   
49.
Interspecific diversity exists in cranial suture closure patterns among mammalian species. Suture closure patterns partly reflect phylogenesis, but it has also been claimed that it is influenced by biomechanical factors. Here we provide the first report on the cranial suture closure pattern in water deer. Among cervids, the water deer is an exceptional species, as it is the only one without antlers. Instead, the male water deer possess prominent canines, which are utilized during male-male combats. This unique morphological setting allowed us to examine whether the presence of prominent canines affects cranial suture closure. We found that the only sexual difference in cranial suture closure pattern is the closure of the interfrontal suture in males, which is found in some other cervid species as well. Except for the interfrontal suture closure, timing and sequence of cranial suture closure were comparable between both sexes, suggesting that the presence of prominent canines in males has no influence on cranial suture closure pattern. Our results indicate that interfrontal suture closure in males is a phylogenetic pattern, i.e. an apomorphy for Capreolini, Hydropotini and Alceini.  相似文献   
50.
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