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21.
Forest restoration efforts in Australia's Wet Tropics establish <100 ha/year, compared with 20‐year average clearing rates of 1661 ha/year. Establishment costs are serious impediments to restoration efforts. Costs range from $25,000 to $67,000/ha, compared with less than $5,000/ha in other areas using other methods. Some of this difference stems from methods used to plant trees. Augered holes are used commonly in environmental plantings, whereas planting spades are used mostly in forestry plantings. To determine the most cost‐effective planting method between auger and spade planting methods, we compared the planting costs and the survival and growth of seedlings of local rainforest species, The speed of planting with a spade is on average four times quicker than with an auger, whereas the survival (range = 89–94%, spade vs auger respectively), and growth (slightly greater height growth for auger planted individuals) rates were only marginally different. Given these results, using planting spades is a cost‐effective alternative to augering holes.  相似文献   
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Primates, especially apes, are popular with the public, often attracting large crowds. These crowds could cause behavioral change in captive primates, whether positive, neutral, or negative. We examined the impact of visitors on the behavior of six western lowland gorillas (Gorilla gorilla gorilla), observing the troop over 6 weeks during high season (4.5 hr/day, 35 days, May–July 2016). We used focal scan sampling to determine activity budget and enclosure usage, and focal continuous sampling to identify bouts of anxiety-related behavior (visitor-directed vigilance, self-scratching, and aggression). Both daily zoo-entry numbers (VGATE) and instantaneous crowds at the exhibit (VDENSITY) were measured. Overall, VGATE had little effect across behaviors. However, consistent with the more acute time frame of measurement, VDENSITY was a better predictor of behavior; at high crowd volumes, we observed significant group-level changes in activity budget (increased inactivity, increased locomotion, and decreased environment-related behaviors), increase in some anxiety-related behaviors, and decreased enclosure usage. Although contributing similar effects, it could not be determined if crowd numbers, composition, or noise most affected the troop, nor any chronic effects of exposure to large crowds. Nevertheless, our findings suggest that measures to minimize the impacts of large crowds at the exhibit would be beneficial. Furthermore, we highlight potential discrepancies between common methods for measuring visitor numbers: VGATE is less sensitive to detecting visitor effects on behavioral indices than VDENSITY. Future studies should appropriately match the biological time frame of welfare indicators and visitor measures used to ensure the reliability of findings.  相似文献   
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As a result of intensive exploitation, disturbed forests now dominate large areas of lowland tropical rainforest in South‐East Asia. The genus Macaranga comprises some of the most important pioneer tree species of the region, among them M. beccariana and M. hypoleuca, two closely related obligate ant‐plants pollinated by thrips. We used nuclear and plastid DNA markers to address questions of genetic diversity and population structure. Twelve plastid haplotypes were detected among 281 samples, three of which were shared between the two study species. Hybrids between the two species appear to be rare. Overall, genetic diversity in both species was moderate to high, with low levels of population differentiation, consistent with other tropical pioneer trees. Genetic structure was generally more pronounced in plastid than in nuclear data, indicating that gene flow via pollen may be more efficient than via seeds. Thrips apparently also serve as efficient pollinators over long distances, perhaps through a combination of passive dispersal by wind and active search for inflorescences in the target area. Our results indicate that M. beccariana and M. hypoleuca populations from recently disturbed habitats do not yet suffer from reduced genetic diversity or increased inbreeding. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 606–621.  相似文献   
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Manjarivolo randrianirinai n. sp. is described from Southern Madagascar (Andohahela massif). Remarks on its ecology and morphology are added and a key to Manjarivolo species is provided as well as a complete photographic iconography of all known species. The scutellum of Aulonocnemini displays an unusual morphology, reported for the first time within Scarabaeoidea. For the first time we provide scanning electron microscope micrographs of the mouthparts of these beetles.  相似文献   
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O cervo-do-pantanal (Blastocerus dichotomus, Cervidae) é uma espécie sul americana ameaçada de extinção. Existe pouca informação sobre a biologia desta espécie, incluindo dieta e requerimentos de habitat. O objetivo deste estudo foi determinar as espécies de plantas forrageadas pelo cervo no Pantanal, Brazil, onde se localiza a maior parte de sua população. A dieta do cervo-do-pantanal foi estudada através de microhistologia de restos vegetais em amostras de fezes. Um total de 41 espécies foram identificadas como componentes da dieta, 32 delas sendo consumidas durante a estação de cheias e 31 na estação seca. A maioria das espécies de plantas detectadas na dieta do cervo-do-pantanal é composta de plantas aqu ticas e/ou que apresentam tolerância a inundaç[otilde]es sazonais ou solos encharcados. Blastocerus pode ser melhor definido como um estrategista "pastador-podador" porque grande parte de sua dieta é composta de brotos de várias espécies arbustivas e macrófitas de folha larga. The marsh deer (Blastocerus dichotomus, Cervidae) is a South American endangered species. There is little information on the biology of this species, including diet and habitat requirements. The objective of this study was to determine the plant species foraged by the marsh deer in the Pantanal wetland, Brazil, where most of its population is found. Marsh deer's diet was studied through microscopic analysis of fecal samples for remnants of plant species. A total of 41 species were identified as components of the diet, 32 of them found to be consumed during the flooding season and 31 in the dry season. Most plant species detected in the marsh deer's diet are aquatic and/or present tolerance to seasonal flooding and water-logged soils. Blastocerus could be best defined as a grazer-browser strategist because large part of its diet is composed of shoots of several species of shrub and broad-leaved aquatic macrophytes.  相似文献   
28.
Background: Tropical rainforests represent the most species-rich and at the same time the most fragmented terrestrial biome on Earth. Fragmentation of tropical rainforests is having wide-ranging consequences for the maintenance of local species diversity and community assembly patterns.

Aims: To examine floristic changes and changes in community phylogenetic structure in the forest fragment over the past five decades.

Methods: A new taxonomic diversity algorithm (within-family diversity) was developed to assess floristic changes in the forest fragment. Community phylogenetic structure was then compared before and after fragmentation.

Results: Taxonomic diversity changed greatly among families, with changes occurring randomly across the phylogeny. The forest fragment had higher phylogenetic diversity, higher mean pair-wise phylogenetic distance, but lower mean nearest-neighbour distance. The community phylogenetic structure has changed significantly from clustering to dispersion.

Conclusions: High species turnover occurred in the forest fragment. While shade-tolerant species have been lost, and ruderal and alien species have been added, overall phylogenetic diversity has increased with species being more phylogenetically distant. Competitive exclusion, which was related to the relatively drier conditions in the forest after fragmentation, led the plant community phylogenetic structure to be more dispersed.  相似文献   
29.
Autogamous species are usually distinguishable from xenogamous relatives by smaller flowers, fewer or even no floral rewards and lower pollen–ovule (P/O) ratios. Many Rhipsalis spp. are small flowered, selfing and include the most widespread species in Cactaceae. However, Rhipsalis also includes a large number of narrowly endemic species and is most diverse in the Atlantic rainforests of Brazil. To investigate the evolution of floral function and the correlation between floral function and range size, we analysed display size, floral reward and P/O ratios of Rhipsalis and its closest relatives, reconstructed ancestral traits and related these patterns to the distributions and range sizes of the species. Display size and sugar amount are reduced in subgenera Goniorhipsalis and Rhipsalis and secondarily increased in Phyllarthrorhipsalis, whereas the P/O ratio is decreased in subgenera Rhipsalis and Phyllarthrorhipsalis. We interpret this pattern as a switch from a predominantly xenogamous to an autogamous reproductive system, followed by a return to a predominantly xenogamous system. None of the floral parameters shows significant correlations with range size, except for display size. Nevertheless, those species with the smallest flowers, lowest sugar amounts per flower and lowest P/O ratios occur either outside southeastern Brazil and/or have comparatively large distribution ranges. Almost all Rhipsalis spp. occurring outside the Atlantic rainforests are restricted to the clade formed by subgenera Rhipsalis and Phyllarthrorhipsalis. Thus, we believe that the evolution of an autogamous reproduction system enabled this lineage of Rhipsalis to diversify and spread in the Atlantic rainforests, in the rest of the Neotropics and even spread to the Old World, where it is the only member of the family.  相似文献   
30.
Negative frequency‐dependent selection among species is a key driver of community diversity in natural systems, but the degree to which negative frequency‐dependent selection shapes patterns of survival and genetic diversity within species is poorly understood. In a 5‐year field experiment, we show that seedlings of a tropical palm with rare genotypes had a pronounced survival advantage over seedlings with common genotypes, with effect sizes comparable to that of light availability. This ‘rare genotype advantage’ led to an increase in population‐wide genetic diversity among seedlings compared to null expectations, as predicted by negative frequency‐dependent selection, and increased reproductive success in adult trees with rare genotypes. These results suggest that within‐species negative frequency‐dependent selection of genotypes can shape genetic variation on ecologically relevant timescales in natural systems and may be a key, overlooked source of non‐random mortality for tropical plants.  相似文献   
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