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951.
The species of the Neoserica
(sensu lato)
calva group are revised. Neoserica
calva Frey, 1972, comb. n. is redescribed. Thirteen new species are described from China and South Korea: Neoserica
ailaoshanica
sp. n., Neoserica
anonyma
sp. n., Neoserica
calvoides
sp. n., Neoserica
gulinqingensis
sp. n., Neoserica
koelkebecki
sp. n., Neoserica
liangi
sp. n., Neoserica
luxiensis
sp. n., Neoserica
menghaiensis
sp. n., Neoserica
mengi
sp. n., Neoserica
taipingensis
sp. n., Neoserica
zheijangensis
sp. n., Neoserica
zhibenshanica
sp. n., and Neoserica
zongyuani
sp. n. A key to Sericini genera with multilamellate antenna and species groups of Neoserica of mainland Asia as well as a key to species of the Neoserica
calva group are provided. A map of species distribution is given, habitus and male genitalia are illustrated. 相似文献
952.
Valentina Castro-Huertas James P. Pitts Juanita Rodriguez Cecilia?Waichert Fernando Fernández 《ZooKeys》2014,(443):35-44
New records of genera and species of spider wasps (Hymenoptera: Pompilidae) from Colombia are provided. Agenioideus, Cryptocheilus, Evagetes, Mystacagenia, and Xerochares are newly recorded genera from Colombia. Nineteen species are first recorded from Colombia: Aimatocare
vitrea (Fox); Ageniella
azteca (Cameron); Ageniella
curtipinus (Cameron); Ageniella
fallax (Arlé); Ageniella
hirsuta Banks; Ageniella
pilifrons (Cameron); Ageniella
pretiosa Banks; Ageniella
sanguinolenta (Smith); Ageniella
zeteki (Banks); Agenioideus
birkmanni (Banks); Aporus (Aporus) cuzco Evans; Aporus (Cosmiaporus) diverticulus (Fox); Aporus (Notoplaniceps) canescens Smith; Euplaniceps
exilis (Banks); Euplaniceps
herbertii (Fox); Irenangelus
clarus Evans; Mystacagenia
bellula Evans; Phanochilus
nobilitatus (Smith) and Xerochares
expulsus Schulz. The following species and genera have their occurence ranges expanded for South America: Ageniella
azteca (Cameron); Ageniella
zeteki (Banks); Agenioideus
birkmanni (Banks); and Xerochares
expulsus Schulz; Cryptocheilus Panzer; and Xerochares Evans. 相似文献
953.
Forest biomass carbon sinks in East Asia,with special reference to the relative contributions of forest expansion and forest growth 总被引:3,自引:0,他引:3
Jingyun Fang Zhaodi Guo Huifeng Hu Tomomichi Kato Hiroyuki Muraoka Yowhan Son 《Global Change Biology》2014,20(6):2019-2030
Forests play an important role in regional and global carbon (C) cycles. With extensive afforestation and reforestation efforts over the last several decades, forests in East Asia have largely expanded, but the dynamics of their C stocks have not been fully assessed. We estimated biomass C stocks of the forests in all five East Asian countries (China, Japan, North Korea, South Korea, and Mongolia) between the 1970s and the 2000s, using the biomass expansion factor method and forest inventory data. Forest area and biomass C density in the whole region increased from 179.78 × 106 ha and 38.6 Mg C ha?1 in the 1970s to 196.65 × 106 ha and 45.5 Mg C ha?1 in the 2000s, respectively. The C stock increased from 6.9 Pg C to 8.9 Pg C, with an averaged sequestration rate of 66.9 Tg C yr?1. Among the five countries, China and Japan were two major contributors to the total region's forest C sink, with respective contributions of 71.1% and 32.9%. In China, the areal expansion of forest land was a larger contributor to C sinks than increased biomass density for all forests (60.0% vs. 40.0%) and for planted forests (58.1% vs. 41.9%), while the latter contributed more than the former for natural forests (87.0% vs. 13.0%). In Japan, increased biomass density dominated the C sink for all (101.5%), planted (91.1%), and natural (123.8%) forests. Forests in South Korea also acted as a C sink, contributing 9.4% of the total region's sink because of increased forest growth (98.6%). Compared to these countries, the reduction in forest land in both North Korea and Mongolia caused a C loss at an average rate of 9.0 Tg C yr?1, equal to 13.4% of the total region's C sink. Over the last four decades, the biomass C sequestration by East Asia's forests offset 5.8% of its contemporary fossil‐fuel CO2 emissions. 相似文献
954.
Neil Saintilan Nicholas C. Wilson Kerrylee Rogers Anusha Rajkaran Ken W. Krauss 《Global Change Biology》2014,20(1):147-157
Mangroves are species of halophytic intertidal trees and shrubs derived from tropical genera and are likely delimited in latitudinal range by varying sensitivity to cold. There is now sufficient evidence that mangrove species have proliferated at or near their poleward limits on at least five continents over the past half century, at the expense of salt marsh. Avicennia is the most cold‐tolerant genus worldwide, and is the subject of most of the observed changes. Avicennia germinans has extended in range along the USA Atlantic coast and expanded into salt marsh as a consequence of lower frost frequency and intensity in the southern USA. The genus has also expanded into salt marsh at its southern limit in Peru, and on the Pacific coast of Mexico. Mangroves of several species have expanded in extent and replaced salt marsh where protected within mangrove reserves in Guangdong Province, China. In south‐eastern Australia, the expansion of Avicennia marina into salt marshes is now well documented, and Rhizophora stylosa has extended its range southward, while showing strong population growth within estuaries along its southern limits in northern New South Wales. Avicennia marina has extended its range southwards in South Africa. The changes are consistent with the poleward extension of temperature thresholds coincident with sea‐level rise, although the specific mechanism of range extension might be complicated by limitations on dispersal or other factors. The shift from salt marsh to mangrove dominance on subtropical and temperate shorelines has important implications for ecological structure, function, and global change adaptation. 相似文献
955.
Douglas A. Kelt Peter L. Meserve 《Biological reviews of the Cambridge Philosophical Society》2014,89(3):705-722
South America spans about 44° latitude, covers almost 18 million km2, and is second only to Africa in continental mammal species richness. In spite of this richness, research on the status of this fauna and on the nature and magnitude of contemporary threats remains limited. Distilling threats to this diverse fauna at a continental scale is challenging, in part because of the limited availability of rigorous studies. Recognizing this constraint, we summarize key threats to small mammals in South America, emphasizing the roles of habitat loss and degradation, direct persecution, and the increasing threat of climate change. We focus on three regional ‘case studies’: the tropical Andes, Amazonia and adjacent lowland regions, and the southern temperate region. We close with a brief summary of recent findings at our long‐term research site in north‐central Chile as they pertain to projected threats to this fauna. Habitat alteration is a pervasive threat that has been magnified by market forces and globalization (e.g. extensive agricultural development in Amazonia), and threatens increasing numbers of populations and species. Climate change poses even greater threats, from changes in rainfall and runoff regimes and resulting changes in vegetative structure and composition to secondary influences on fire dynamics. It is likely that many changes have yet to be recognized, but existing threats suggest that the future may bring dramatic changes in the distribution of many mammal taxa, although it is not clear if key habitat elements (vegetation) will respond as rapidly as climatic factors, leading to substantial uncertainty. Climate change is likely to result in ‘winners’ and ‘losers’ but available information precludes detailed assessment of which species are likely to fall into which category. In the absence of long‐term monitoring and applied research to characterize these threats more accurately, and to develop strategies to reduce their impacts, managers already are being faced with daunting challenges. As the line between ‘pure’ and ‘applied’ research blurs in the face of converging interests of scientists and society we hope that solutions to these critical issues will be incorporated in addressing anticipated conservation crises. 相似文献
956.
957.
An aggregate-attached bacterium, strain 88/2-7, was isolated from samples of the Southern Ocean and investigated in a polyphasic approach. The novel marine isolate is an aerobic, Gram-negative, oxidase- and catalase-positive, non-motile short rod and grows in form of cream-colored colonies. Growth was observed at 5-35 degrees C. The bacterium tolerated concentrations of 0-13% (w/v) NaCl and utilized a relatively restricted spectrum of carbon sources. The analysis of the fatty acids revealed 18:1 cis 9 (18:1omega9c) as main fatty acid. The G+C content of the DNA was approximately 42 mol%. The sequence of the 16S rDNA assigned strain 88/2-7 to the gamma-subclass of Proteobacteria with a similarity of 99.65% to Psychrobacter proteolyticus (DSM 13887T). A DNA-DNA-hybridization study showed only 26.8% renaturation to the respective strain. Based on the morphological, physiological and molecular properties of the new isolate, the name Psychrobacter nivimaris sp. nov. (type strain 88/2-7T) is proposed. 相似文献
958.
Lange CA Kotte K Smit M van Deventer PW van Rensburg L 《International journal of phytoremediation》2012,14(9):908-924
Rehabilitation of mine tailings dams is often a challenge due to a lack of nutrients and a poor humus reservoir prevailing in tailings soils. This is especially true for establishing longer lived species such as trees. For these reasons the effects of different soil ameliorants (woodchips compost, vermicompost, mature sewage sludge), added to the root system of Karee (Searsia lancea) saplings were tested in pot trials. Those pots were filled with platinum and gold tailings substrate as well as red clay soil, respectively. For three months plants remained in a greenhouse and were subsequently moved to a test field outside. Throughout the test period regular chl a fluorescence measurements were taken and subjected to JIP-test quantifying changes in photosynthetic vitality status. Additionally, growth measurements and one-off leaf analysis were carried out. Test plants growing on mine tailings experienced an up to 35% higher average photosynthetic vitality (PI(ABS)) and improved nutrient supply, when treated with mature sewage sludge. Consequently, sewage sludge treated plants showed a higher biomass build-up rate and an up to 55% higher diameter growth, compared to control. In summary the experiments present a low cost alternative for reforestation enterprises on platinum and gold tailings dams in South Africa. 相似文献
959.
Mohlamatsane M. Mokhatla G. John Measey Christian T. Chimimba Berndt J. van Rensburg 《Diversity & distributions》2012,18(5):470-480
Aim To determine the spatial relationship between areas where different frog breeding groups occur and elevated anthropogenic activities, and the conservation implications thereof. Location South Africa. Methods Data on frog distribution ranges for the southern African sub‐region were used to identify biogeographical areas within South Africa. A random draw technique was used to determine whether areas where different frog breeding groups occur were characterized by higher levels of anthropogenic threats than expected by chance. Four measures (human population density, percentage land transformation, percentage protected area and invasive alien plants richness) expected to reflect threats were analysed. Results Terrestrial‐breeders were more often spatially associated with areas of threat than expected by chance in three of the seven biogeographical regions examined with land transformation and invasive alien plant richness being most significant. The south central was the only region where terrestrial‐breeders were spatially congruent with protected areas. Areas where stream‐breeders occur were spatially congruent with anthropogenic threats (with alien plants being most consistent) in five of the seven regions examined while protected areas were well represented in four of the seven regions. Non‐significant results were found for permanent and temporary aquatic‐breeders at both the national and the biogeographical scale. Main conclusions By analysing data at the sub‐continental scale we were able to identify regional threats to amphibians traditionally classified at species‐specific scales. Our study recognized land transformation and alien invasive plants as significant threats to areas important for the long‐term breeding success of stream and terrestrial amphibians in South Africa. Areas where different breeding groups occur in the south‐western Cape showed the greatest spatial congruence with the threats examined. Areas where terrestrial breeding frogs occur are not well represented in the current conservation network. This has important implications in addressing the current status of threats on amphibians in a biogeographical context. 相似文献
960.
JASON P. MARSHAL 《Austral ecology》2012,37(3):401-412
The factors that affect resource selection by a foraging herbivore can vary according to the resources or conditions associated with particular levels of organization in the environment, and to the scales over which the herbivore perceives and responds to those resources and conditions. To investigate the role of forage in this hierarchical process, we studied resource selection by a mixed‐feeding large herbivore, the impala (Aepyceros melampus). We focussed on three spatial scales: plant species, feeding station and feeding patch. In paired sites where impala were and were not observed, we identified the plant species from which animals fed, the attributes of the plants, and the characteristics of the broader site. Across all three scales, plant species available as forage was central in determining resource selection by impala. At the species level, that effect was modified by the nutritional quality (greenness) and whether it was during a period of forage abundance or scarcity (season). At the feeding‐station level, overall greenness and biomass of the station were important, but their effects were modified by the season. At the feeding‐patch level, broader‐scale factors such as the type of vegetation cover had an important influence on resource selection. The grass Panicum maximum was a preferred forage species and a key resource determining the locations of feeding impala. Our findings support the idea that selection by a foraging herbivore at fine scales (i.e. diet selection) can have consequences for broader‐scale selection that result in observed patterns of habitat use and animal distribution. 相似文献