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61.
华南虎圈养种群的统计分析   总被引:3,自引:0,他引:3  
对《华南虎谱系》307 只登录个体的统计表明, 其圈养的历史有46 年。在人工繁殖的38 年中产122 胎287仔。现存圈养华南虎分散在全国22 家单位, 有57 只个体, 性比M∶F = 1185 , 能成功繁殖后代的个体仅5 只(只占818 %) , 是一个衰退的种群。通过SPARKS 和GENES 软件分析发现: 从1977 年开始, 圈养种群的基因多样性便逐渐下降而近交系数却不断增加。  相似文献   
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Coexistence of sympatric species is mediated by resource partitioning. Pumas occur sympatrically with jaguars throughout most of the jaguar's range but few studies have investigated space partitioning between both species. Here, camera trapping and occupancy models accounting for imperfect detection were employed in a Bayesian framework to investigate space partitioning between the jaguar and puma in Emas National Park (ENP), central Brazil. Jaguars were estimated to occupy 54.1% and pumas 39.3% of the sample sites. Jaguar occupancy was negatively correlated with distance to water and positively correlated with the amount of dense habitat surrounding the camera trap. Puma occupancy only showed a weak negative correlation with distance to water and with jaguar presence. Both species were less often present at the same site than expected under independent distributions. Jaguars had a significantly higher detection probability at cameras on roads than at off-road locations. For pumas, detection was similar on and off-road. Results indicate that both differences in habitat use and active avoidance shape space partitioning between jaguars and pumas in ENP. Considering its size, the jaguar is likely the competitively dominant of the two species. Owing to its habitat preferences, suitable jaguar habitat outside the park is probably sparse. Consequently, the jaguar population is likely largely confined to the park, while the puma population is known to extend into ENP's surroundings.  相似文献   
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Gray literature and data from unpublished sources can provide important scientific information that has not been published scientifically. The Persian leopard (hereafter leopard) Panthera pardus saxicolor is classed as endangered on the Red List of the International Union for Conservation of Nature and also is one of the least‐studied subspecies of leopard. It occurs in the Caucasus and Central and Southwest Asia. Iran contains more than 75% of the leopard's extant range, and the leopard population in this country serves as a source for neighboring countries. In this study, we determined the distribution and human‐caused mortality of leopards in Iran, by reviewing unpublished data and Farsi gray literature (which includes government reports) between 1 January 2010 and 30 December 2018. We created the most recent distribution map of the leopard in Iran. Our data display that human‐caused mortality of leopard in Iran mostly includes poaching and intentional poisoning, and roadkill.  相似文献   
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Because tiger Panthera tigris numbers are regulated by their prey base, prey abundance needs to monitored and estimated reliably. Recently, distance sampling has been adopted as the most appropriate method and is now becoming the standard monitoring protocol in all tiger range countries in south Asia. However, the accuracy of the density estimates generated by this method has not been assessed. From total counts within habitat blocks, we obtained accurate density estimates of ungulates within three main habitats in Bardia National Park, Nepal. We then applied the distance sampling method in the same habitats and compared the results. Distance sampling on foot in dense habitats (riverine forest and tallgrass floodplain) violated method assumptions, and sampling from vehicle along roads gave biased estimates. Sampling from elephant back worked well in all habitat types, but owing to their behaviour, the density of barking deer Muntiacus muntjak was underestimated. The accuracy of the estimates varied with sampling effort; for the very abundant chital deer Axis axis , estimates varied markedly at <200 animal observations, but converged at larger sample sizes to a similar point estimate as intensive block counts when approaching 300 observations. For the less abundant species, with <20 observations along >100 km of transect lines, the confidence intervals were quite high, and, hence, of limited value for detecting short-term populations trends. It is therefore difficult to obtain accurate density estimates of rare species by the distance method. In areas consisting of dense habitats, we recommend that the food base of tiger be estimated by distance sampling from elephant back, not on foot, directed at the main and most abundant prey species. For rare species, encounter rates obtained simultaneously may then serve as indices of relative abundances.  相似文献   
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本文采用PCR和质粒克隆测序方法,获得了华南虎线粒体D-loop区的480bp序列和东北虎、孟加拉虎线粒体D-loop区的503bp序列;同时还获得了这三个虎亚种和金钱豹线粒体ND5基因5’端309bp的部分序列。根据D-loop序列分析,华南虎与孟加拉虎、东北虎的平均距离(p-distance)分别为0.11088和O.11087,而东北虎与孟加拉虎间的平均距离为0.00994;根据ND5序列分析,华南虎与孟加拉虎、东北虎的平均距离分别为0.11434和0.11758,而东北虎与孟加拉虎间的平均距离为0.00324。三个虎亚种的mtDNA D-loop和ND5序列比较表明,华南虎是这三个虎亚种中最为古老的亚种。  相似文献   
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Leopard diets in the Kasoje area of the Mahale Mountains National Park, Tanzania, were analysed by inspecting prey remains in 256 scats. This area is unique as leopard density is high despite a relatively low density of medium-sized ungulates, regarded as the most preferred prey of leopards. At least eleven prey mammal species were confirmed in the scats. Small prey mammals up to 10 kg comprised 91.4% of the relative biomass consumed; the mean prey biomass in each scat was 7.6 kg. Blue duiker (31.2%) was the most dominant prey species, followed by the red colobus (29.2%), semi-terrestrial Cercopithecinae (the vervet monkey and yellow baboon combined) (10.5%) and the red-tailed monkey (9.9%). At the order level, the most consumed prey taxon was Primates (53.8%), followed by Cetartiodactyla (39.6%) and Rodentia (5.8%). Among primates, the blue monkey was the most preferred prey species, followed by the red colobus and semi-terrestrial Cercopithecinae. High consumption of primates is a unique characteristic of the leopards in Mahale. This trend exemplifies the flexibility of leopards in their choices of prey, and such flexibility may be one of the underlying reasons for leopards exhibiting the broadest global distribution among all wild felid species.  相似文献   
69.
东北虎幼体消化系统蛋白水解酶的初步研究   总被引:1,自引:0,他引:1  
蛋白水解酶在许多生命活动中是必需的物质(Vassalli and Pepper,1994)。蛋白质的酶解修饰(Xuet al.,1999)、细胞迁移、组织再生与修复、消化系统对蛋白质的消化等均与蛋白水解酶有关(Baimbridgeet al.,1992),且蛋白水解酶功能失调会导致许多疾病(Teichertet al.,1989)。东北虎(  相似文献   
70.
Accurate assessments of the status of threatened species and their conservation planning require reliable estimation of their global populations and robust monitoring of local population trends. We assessed the adequacy and suitability of studies in reliably estimating the global snow leopard (Panthera uncia) population. We compiled a dataset of all the peer-reviewed published literature on snow leopard population estimation. Metadata analysis showed estimates of snow leopard density to be a negative exponential function of area, suggesting that study areas have generally been too small for accurate density estimation, and sampling has often been biased towards the best habitats. Published studies are restricted to six of the 12 range countries, covering only 0.3–0.9% of the presumed global range of the species. Re-sampling of camera trap data from a relatively large study site (c.1684 km2) showed that small-sized study areas together with a bias towards good quality habitats in existing studies may have overestimated densities by up to five times. We conclude that current information is biased and inadequate for generating a reliable global population estimate of snow leopards. To develop a rigorous and useful baseline and to avoid pitfalls, there is an urgent need for (a) refinement of sampling and analytical protocols for population estimation of snow leopards (b) agreement and coordinated use of standardized sampling protocols amongst researchers and governments across the range, and (c) sampling larger and under-represented areas of the snow leopard's global range.  相似文献   
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