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101.
The very rapid development of the road infrastructure in recent years has adversely affected the natural environment. The main effects of this have been the loss or deteriorating quality of habitats, the mortality of animals due to collisions with road vehicles, the withdrawal of birds as a result of disturbance and excessive noise in the neighbourhood of roads. In this study, we attempted to define the influence of a busy road on a breeding community of woodland birds. Individuals were counted using the point method at 54 observation points located at three various distances (60, 310, 560 m) from the road. At each point, we determined the habitat parameters and the intensity of noise. In total, 995 individuals of 39 species were recorded on the study plot. This study showed that the area was homogeneous with respect to habitat. The number of birds per point increased with distance from the road. Species diversity was lower near the road. The density of nine common species increased with distance from the road. Great Tit Parus major and Song Thrush Turdus philomelos preferred the neighbourhood of the road, whereas the numbers of the other species were the highest in the middle row of points. The number and species diversity of birds were correlated with the pattern of sound propagation across our study area. Our results showed that the species particularly sensitive to road traffic were those nesting near the ground and with low-frequency calls.  相似文献   
102.
The diversity of environmental mycobacteria was studied in water-logged acidic forest soil. Mycobacteria were assessed in upper and lower soil horizons and summer and winter seasons using T-RFLP and sequencing of 16S rRNA gene produced with Mycobacterium-specific primers. Mycobacteria diversity differed between both the two seasons and soil horizons. Cloning revealed the presence of mycobacteria belonging to three major clusters recognized within the genus, i.e. fast-growing, intermediate, and slow-growing species, with unprecedented abundance and diversity of the latter. Two novel clusters of sequences unrelated to the known mycobacteria were identified. This study raises the possibility that forest wetlands could serve as environmental reservoirs for an unexplored diversity of mycobacteria including those related to pathogenic species.  相似文献   
103.
We reviewed studies dealing with regeneration under variable conditions in boreal and hemiboreal forests as affected by different microsite types by tree species functional groups. Generally, the importance of storm-induced microsites for regeneration dynamics in boreal forests depends on several factors: (1) distribution and type of microsites (generated by storm characteristics and stand conditions); (2) viable seed supply (stand history, species dispersal traits and status of surviving trees) and their species’ life history strategy; (3) climatic and site conditions (pre-storm conditions and storm-induced changes); and (4) delayed storm effects, such as retarded falling of trees, favoured vegetation growth, etc. Studies acknowledging the significance of microsites were mostly related to intermediate or severe events, causing sufficient changes in resource levels and growth conditions, and influencing extrinsic factors such as frost heaving, erosion and browsing. Also, the dispersal traits of available tree species, including sprouting and response of surviving trees, such as canopy expansion, should be considered in evaluating microsite importance in individual cases. In intermediate to severe windstorm events, pioneer species are generally profiting most from the additional offer in microsites, requiring bare mineral soil and elevated locations for their establishment and growth. Under gap dynamics, shade-tolerant species benefit from dead wood and elevated locations as these offer safe sites in stands with abundant understorey vegetation.  相似文献   
104.
Plant cover is an easily discernible, recognisable and labile component of the natural environment that reacts to changes in other components. One of the more important components controlling vegetation cover is the soil, and both vegetation and soil are influenced by topography, amongst other things. As it is in the humus-accumulation horizon of soils that vascular plants have most of their roots, these species are capable of reacting to qualitative and quantitative differences in its composition. The relationship between topography, soil and vegetation were assessed on the basis of three catenal sequences representative of Poland's Wigierski (Lake Wigry) National Park. The aim was to determine if changes in soil along the catenae were reflected in changes in plant community (species richness, species composition, and indicator species). We made use of soil analysis, phytosociological analysis of vegetational structure, and Ellenberg indicator values. Correlations between 23 variables allowed distinguishing 6 statistically-significant groups of variables with main ordinating groups being the percentage shares of species indicating relatively dry, slightly moist soils, the combined shares of these species, altitude above sea level and relative elevation. The first two axes of a Principal Components Analysis were strongly related to soil moisture and elevation (axis 1) and to soil fertility (axis 2). Together, these axes accounted for more than 60% of the variability. Within the forest communities, however, fertility was the most important factor. The three catenae differed most in terms of their species richness and least in soil characteristics. An intermediate place was taken by the weighted Ellenberg's indicator values. The lower sections of catenae were found to have more similarity in terms of soil, vegetation and their interrelationships and patterns than the upper parts.  相似文献   
105.
This research aims to make an analysis of significant parameters in wine grape from Czech Republic. It was evaluated pH, content of sugar, ascorbic acid, titratable acidity, total phenolic content and texture properties. For analyzes 5 samples of wine grape were used, harvested during the three periods. The results show that during the ripening of wine grapes there were changes of selected qualitative parameters, particularly of total polyphenols, sugar and some varieties of wine grape also ascorbic acid (significantly in the variety ’Grüner Veltliner’, ’Chardonnay’, ’Pinot Blanc’). Pronounced changes qualitative parameters were among wine grapes harvested the 1st and 2nd seasons. Changes in textural properties also occurred during the harvest and for most varieties between 2nd and 3rd period of harvest. The PCA grouped chemical parameters of wine grape in independent sets and can be used as assessment tool of wine cultivars.  相似文献   
106.
Europe’s woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.  相似文献   
107.
The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one‐day‐old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n = 120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti‐bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42 days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.  相似文献   
108.
Residues of chlorinated pesticides in feed for laying hens, in eggs, poultry organs, potatoes, flour, and human fat tissues were determined by means of gas chromatography using electron recording detector. Further the amount of chlorinated hydrocarbon residues in potatoes from various parts of the South Moravian Region was stated. HCH amounts in human fat tissues recorded in Czechoslovakia were higher than in some West European countries, DDT content being, however, on the same level.  相似文献   
109.
Biological invasions of insects, plants, and fungal pest species often cause substantial disturbance to forest ecosystems and as well as severe socioeconomic impacts. Central Europe acts as a ‘bridge’ between Western and Eastern Europe both ecologically and as an important transit corridor for people. Human activity, including the movement of material goods, increases the risk of invasions. Some species introduced in the past have been established, becoming common and causing serious problems (such as Dreyfusia nordmannianae or Hyphantria cunea). The status, importance and spatial distribution in Slovakia of seven different forest pests recently introduced into Slovak forest ecosystems (Cameraria ohridella, Coleotechnites piceaella, Cryphonectria parasitica, Dothistroma septospora, Ips duplicatus, Parectopa robiniella, Phyllonorycter robiniellus) as well as two others not yet recorded in Slovakia (Anoplophora glabripennis, Phytophthora spp.) is discussed.  相似文献   
110.
Toponyms, or place names have been used to reveal historical land-use patterns based on degree of wetness in the Morava River floodplain. Eleven patch types were plotted on three land cover types representing broad ecological niches with different moisture regimes for four time periods. The river’s simultaneous decrease in sinuosity, which underscores the loss of the landscape’s ecohydrological connectivity, was quanified. The results show that long-term human-dominated land use worked in concert with a naturally occuring seasonal flood regime. The findings strongly indicate that high human density and intensive exploitation can co-exist with a functioning floodplain. Landscape change was interpreted by using a new concept, that of the place-name patch, which can be universally applied to interpret historical land use changes in river basins. Our method is reproducible in river basins with a history of intensive human use.  相似文献   
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