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881.
The development of appropriate technologies for the judicious use of India's 8.11 million ha of salt-affected lands would give increased food, fodder and fuelwood production. A sizeable portion of the salt-affected lands of the Indo-Gangetic plain have been reclaimed through chemical amendments and are being commercially used for arable farming. However, large areas of salt-affected common lands, village and government lands and waste lands near cities, along railway tracks and roads do not have any productive use. Owing to their sparse vegetative cover such lands are vulnerable to further degradation and can be a source of runoff causing floods, especially where cows congregate. Research at the Central Soil Salinity Research Institute, Karnal has generated agroforestry techniques which could enable the economic exploitation of such marginal lands. This paper deals with various aspects of these techniques, which have been applied to over 50 000 ha by 1994. Based on eight to ten years of growth and biomass figures, the most salt-tolerant woody species identified were: Prosopis juliflora, Acacia nilotica, Casuarina equisetifolia, Tamarix articulata, Leptochloa fusca (a palatable forage grass which was found to be a promising primary colonizer of salt lands). Agronomic practices for the successful establishment of trees such as planting methods, amendment use, irrigation, spacing and lopping schedules are discussed. A Prosopis juliflora-leptochloa fusca silvipastoral model was found to be excellent for fuelwood and forage production and for the amelioration of high pH soils. This system, when followed for little more than four years, reclaims alkali soils to such an extent that normal agriculture crops such as Trifolium alexandrinum and T. resupinatum can be grown successfully. A ridge-trench system of tree planting was found to be helpful in alkali soils, the in situ rainwater conservation it led to assisting biomass production. Eucalyptus tereticornis, Populus deltoides and Tectona grandis based agroforestry were promising for reclaimed salt-affected lands. The short- and long-term effects of various tree plantations on the physicochemical properties of the soil and on soil-water relations are also discussed. Agroforestry options for the development of salt-affected lands found in various agroclimatic zones of India are explored. 相似文献
882.
It is proposed that the standard economist's model of optimum land use is extended to include the interaction with land cover and land condition. Such a model allows consideration of the influence of market factors and government policies and programmes on land use patterns and management practices, and the feedback effect on land cover and land condition. Recent developments in the approach to modelling land condition, which include the joint consideration of economic factors and physical processes, are discussed. Factors affecting the pattern of agricultural land use in Australia are then reviewed. The importance of considering economic and physical interactions when assessing land use patterns is increasingly being recognized in research and policy development. If research is to meet the needs of land managers in the future then economists and physical scientists will need to integrate their data modelling capabilities in order to address natural resource management issues. 相似文献
883.
Loren S. Sri-Jayantha Michael T. Doornink Bridget K. Urie 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(1):32
There are limited data on glucocorticoid treatment in dogs. The purpose of this study was to investigate whether dogs of higher body weight experienced more adverse events when receiving glucocorticoid therapy. Data pertaining to glucocorticoid therapy was abstracted from the records of 61 dogs that were prescribed glucocorticoids for treatment of immune-mediated thrombocytopenia or hemolytic anemia from 2014 to 2019. The odds of developing muscle atrophy and polyphagia during therapy were increased by 30% for each 5 kg of additional body weight. Almost half of the dogs (44.3%) fluctuated > 15% from baseline weight during therapy. Dogs whose body condition scored as above ideal were at increased risk (odds ratio = 4.2) for being diagnosed with urinary tract infection. Our findings suggest that standard linear glucocorticoid dosing may place higher body weight dogs at increased risk of developing adverse events. Accelerated glucocorticoid tapering and/or alternative dosing schemes in dogs with higher body weights may be prudent in efforts to improve tolerance and client compliance. 相似文献
884.
C. A. DUIGAN T. E. H. ALLOTT H. BENNION J. LANCASTER D. T. MONTEITH S. T. PATRICK J. RATCLIFFE J. M. SEDA 《水产资源保护:海洋与淡水生态系统》1996,6(1):31-55
1. The environment of the island of Anglesey, North Wales, UK, is described and related to the ecology of the lake systems present. 2. Estimates are given of the number and types of lakes present on the island. Sixteen biological Sites of Special Scientific Interest (SSSIs) have standing water as a recognized habitat feature and their reasons for receiving a conservation designation are discussed. 3. Brief reviews are given of the lacustrine flora, invertebrates, fish and aquatic bird populations of Anglesey and their importance in assessing the conservation value of a site. 4. These reviews are followed by detailed accounts of the current ecology of three of the island's lake systems—Llyn Coron, Llyn Dinam and Llyn Penrhyn—which occur within biological Sites of Special Scientific Interest. Original data are presented on their physical and chemical characteristics, diatom assemblages, macrophyte communities, littoral and open water zooplankton communities and macroinvertebrate assemblages. 5. Artificial enrichment, the introduction of alien species, the legacy of metal mining operations and recreational pressures are identified as the main threats to lake conservation on Anglesey. 6. The Anglesey Wetland Strategy, an informal operational level liaison procedure, is described. Using this mechanism, broad targets and indicative strategies are highlighted by the partner organizations active in wetland conservation on the island, and opportunities for collaboration are developed. 相似文献
885.
886.
Clayton T Larue Joel E Ream Xuefeng Zhou Farhard Moshiri Arlene Howe Michael Goley Oscar C Sparks Steven T Voss Erin Hall Christine Ellis Janice Weihe Qungang Qi Daniela Ribeiro Xiaoping Wei Shirley Guo Artem G Evdokimov Marguerite J Varagona James K Roberts 《Pest management science》2020,76(3):1031-1038
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890.
Nguyen Trang T. T. Nguyen Ha V. H. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):656-658
Plant Foods for Human Nutrition - Bitter gourd fruits contain high amounts of charantin, stigmasterol glucoside and β-sitosterol glucoside, which have been shown to provide health benefits for... 相似文献