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Abstract Neotropical eucoiline genera that have been included in and allied with the Zaeucoila genus group are redescribed. Following character analysis and phylogenetic reconstruction (25 taxa, 96 morphological characters, 1452 ribosomal and mitochondrial characters), this informal genus group was found to be monophyletic, and hence raised to formal recognition as a tribe of eucoilines, namely Zaeucoilini new tribe . Through phylogenetic reconstruction, Aegeseucoela Buffington was determined to be polyphyletic; the type species of Aegeseucoela, A. grenadensis (Ashmead), is transferred to Agrostocynips comb.n. ; the orphaned species, A. flavotincta (Kieffer), is transferred to Marthiella Buffington gen.n. , comb.n. Based on the examination of the holotype of Diranchis flavipes Ashmead, 1900 , this species is transferred to Rhabdeucoela comb.n. , where it is both a junior, subjective synonym of flavipes ( Ashmead, 1894 ) syn.n. and a junior, secondary homonym. Zaeucoilini contains the following genera: Agrostocynips Diaz, Dettmeria Borgmeier, Dicerataspis Ashmead, Lopheucoila Weld, Marthiella Buffington, Moneucoela Kieffer, Moritiella Buffington, Penteucoila Weld, Preseucoela Buffington, Rhabdeucoela Kieffer, Tropideucoila Ashmead and Zaeucoila Ashmead. Characters and character states applicable specifically to Zaeucoilini are defined and illustrated. Characters supporting the monophyly of each genus are discussed. The plesiomorphic host for members of the Zaeucoilini are postulated as agromyzid leaf‐mining Diptera, with one shift within the clade containing Dettmeria, Dicerataspis and Lopheucoila to fruit‐infesting Diptera. New host records are reported for species of Preseucoela, Rhabdeucoela and Zaeucoila. All known hosts for the species of each genus are reported, as are known distributions and locations of type specimens.  相似文献   
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ABSTRACT Conversion of native winter range into producing gas fields can affect the habitat selection and distribution patterns of mule deer (Odocoileus hemionus). Understanding how levels of human activity influence mule deer is necessary to evaluate mitigation measures and reduce indirect habitat loss to mule deer on winter ranges with natural gas development. We examined how 3 types of well pads with varying levels of vehicle traffic influenced mule deer habitat selection in western Wyoming during the winters of 2005–2006 and 2006–2007. Well pad types included producing wells without a liquids gathering system (LGS), producing wells with a LGS, and well pads with active directional drilling. We used 36,699 Global Positioning System locations collected from a sample (n = 31) of adult (>1.5-yr-old) female mule deer to model probability of use as a function of traffic level and other habitat covariates. We treated each deer as the experimental unit and developed a population-level resource selection function for each winter by averaging coefficients among models for individual deer. Model coefficients and predictive maps for both winters suggested that mule deer avoided all types of well pads and selected areas further from well pads with high levels of traffic. Accordingly, impacts to mule deer could probably be reduced through technology and planning that minimizes the number of well pads and amount of human activity associated with them. Our results suggested that indirect habitat loss may be reduced by approximately 38–63% when condensate and produced water are collected in LGS pipelines rather than stored at well pads and removed via tanker trucks. The LGS seemed to reduce long-term (i.e., production phase) indirect habitat loss to wintering mule deer, whereas drilling in crucial winter range created a short-term (i.e., drilling phase) increase in deer disturbance and indirect habitat loss. Recognizing how mule deer respond to different types of well pads and traffic regimes may improve the ability of agencies and industry to estimate cumulative effects and quantify indirect habitat losses associated with different development scenarios.  相似文献   
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ABSTRACT The western pond turtle (Actinemys marmorata) is a species of conservation concern over much of its range and is listed as endangered in Washington State. From 2000 to 2004, we used radiotelemetry to document survival and mortality factors of head-started western pond turtles (n = 68) released into Pierce National Wildlife Refuge in southwestern Washington. Survival estimates for first year and older turtles ranged from 86% to 97% and overlapping confidence intervals indicated no detectible differences among age classes or among years. Subadult turtles released at ≥90-mm carapace length apparently avoided capture by most aquatic predators, indicating that terrestrial predators should be the focus of research and management where predation on larger age-classes is a concern. High annual survival combined with the documented nesting by ≥7-year-old female head-started turtles in Washington suggest that recruitment of adults is being achieved; however, head-starting is only practical as an interim solution and strategies for effective removal of aquatic predators must be developed and implemented where natural recruitment is inadequate to maintain populations.  相似文献   
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ABSTRACT Long-term monitoring programs must use informative yet cost-effective methods. Occupancy estimates that incorporate detection probabilities are used with increasing frequency to describe species status and make management recommendations. Estimating changes in the occupancy of points over time in response to management actions or environmental changes may be especially useful for management of the Palm Springs round-tailed ground squirrel (Spermophilus tereticaudus chlorus), a subspecies covered under the Coachella Valley Multiple Species Habitat Conservation Plan and Natural Community Conservation Plan. In 2002 and 2003, we estimated occupancy and detection probability of ground squirrels across lands modeled as ground squirrel habitat by the Scientific Advisory Committee for the Habitat Conservation Plan and tested a priori hypotheses about how occupancy varied among vegetation and substrate types. In the 2003 study, we asked whether these associations were affected by winter rains after the 2002 drought year. Occupancy in 2003 was estimated at 0.99 (SE = 0.01) in Western honey mesquite (Prosopis glandulosa) on dunes and hummocks, and occupancy of the remaining modeled habitat was best described by distance to mesquite, with the occupancy probability decreasing with increasing distance from mesquite on dunes or hummocks. The best-supported model in 2002 described the distribution of ground squirrels as a function of only vegetation and substrate type. However, the best-supported models in 2003 suggested that distance to mesquite was a component of the occupancy of non-mesquite vegetation. Mesquite seems to provide high-quality habitat that can support ground squirrels at high occupancy probabilities that may breed successfully every year. In contrast, other vegetation types provide low-quality habitat that can only support ground squirrels at low occupancy probabilities that may only breed occasionally. Mesquite could be an essential refugium during drought years, and the 4 best-supported models in 2003 suggest that restoration of mesquite beginning near currently occupied mesquite patches could be critical for maintaining ground squirrel populations on the preserves.  相似文献   
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ABSTRACT Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region of the United States and Canada is most sensitive to nest success, and nest success is most strongly influenced by predation. We evaluated the efficacy of reducing predator populations to improve nest success of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005–2007. We monitored 7,489 nests on 7 trapped and 5 nontrapped sites. Trappers annually removed an average of 245 predators per trapped site, and we found nest success to be 1.4–1.9 times greater on trapped sites than nontrapped sites, depending on year. Nest success was greater on both trapped and nontrapped sites when compared with a study conducted in the same areas in the mid-1990s, likely because of changes in red fox (Vulpes vulpes) and coyote (Canis latrans) population dynamics. Nests initiated midseason had higher daily survival rates (DSR) than those initiated earlier or later in the season. Daily survival rates for nests in the middle of the nesting cycle were higher than for nests that were early in laying or late in incubation. Nests near the periphery of trapped sites had slightly higher DSRs than nests in the center of trapped sites. Predator reduction at the township scale provides managers with an effective tool to improve nest success at large spatial scales.  相似文献   
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Abstract 1. Sugar‐rich honeydew excreted (‘produced’) by insects feeding on phloem sap is a key energy flow in a range of temperate and tropical ecosystems. The present study measured honeydew produced by Ultracoelostoma sp. (Homoptera: Coelostomidiidae) scale insects feeding on Nothofagus solandri var. solandri (Hook f.) Oerst. trees in a temperate evergreen forest in New Zealand. Simultaneous measurements of environmental variables and canopy photosynthesis were conducted to allow separation of host‐tree and environmental determinants of honeydew production. These relationships were further examined in experiments where canopy photosynthesis was manipulated by shading or plant nitrogen levels increased by foliar spray. 2. Rates of honeydew production varied nine‐fold from a maximum (± 1 SE) of 64.4 ± 15.2 mg dry mass m−2 bark h−1 in early summer (December) to a minimum of 7.4 ± 4.2 mg m−2 h−1 in winter (August). Rates of production measured 1.4 m from the base of the trees’ stems varied significantly with stem diameter, and were higher on medium‐sized (18 cm diameter) than small or large stems. 3. Rates of production were significantly related to environmental conditions over the hours preceding measurement (air temperature and air saturation deficit averaged over the preceding 24 and 12 h respectively). There was no evidence that rates of production were directly related to short‐term changes in the supply of carbohydrates from the canopy (either when compared with measurements of unmanipulated photosynthetic rate, or after sugar levels were manipulated by shading 80% of host‐trees’ leaf area), or to changes in phloem nitrogen content. 4. The results show that there is no clear effect of host‐tree carbon supply on honeydew production; if production is related to photosynthesis, the effect of this is much less important that the large and significant direct effect of environmental conditions on honeydew production.  相似文献   
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