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21.
农业信息化是新农村建设的重要环节。本文从农业网站、农业数据库、农业专家系统、农业管理信息系统、农业多媒体等5个方面阐述了广东省农业信息化发展的现状,并对农业信息化效果进行了分析,然后指出农业信息化中存在的问题,最后提出了发展建议与对策。  相似文献   
22.
通过对福建省66个站近44年的历年降水资料分析,阐述暴雨、大暴雨、特大暴雨的时空分布特点及对农业生产的影响。结果表明福建各类型暴雨主要发生在雨季和夏季,雨季为暴雨的第一高峰期;夏季为大暴雨和特大暴雨第一高峰期;秋冬季和春雨季的各类暴雨出现频率较小;暴雨的地理分布相对均衡,而大、特大暴雨的高发区在沿海地区。各类型暴雨以暴雨为主,但给农业生产造成严重损失的通常是大、特大暴雨。  相似文献   
23.
根据陕北农牧交错带的生态环境特点以及牧草生长发育过程对水热资源的要求和利用效率,运用迈阿密模型定量估算陕北农牧交错带七县区牧草自然生产力。并与牧草现实生产力进行比较。研究表明:陕北农牧交错带牧草现实生产力仅为自然生产力的30.80%。基本掌握了该区牧草生产力状况和特点,并据此提出了相应的开发战略和实施途径。  相似文献   
24.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.  相似文献   
25.
北京市蔬菜标准化基地存在的问题与对策研究   总被引:1,自引:0,他引:1  
为推进农业标准体系落地,加快蔬菜的产业化进程,分析了北京市蔬菜产业及蔬菜标准化基地现状,汇总出推广基地标准化过程中存在的各种问题,并提出了提升农产品质量安全、推进蔬菜品牌建设等对策建议。  相似文献   
26.
In 1999, the Grain for Green Project was implemented by the Chinese government. Since then, the vegetation of Zuli River Basin, a semi-arid river basin of the Chinese Loess Plateau, has been greatly changed. Clearly understanding the impact of natural and artificial factors on vegetation change is important for policy making and ecosystem management. In this study, spatio-temporal variations in vegetation cover in Chinese Zuli River Basin during 1999–2016 were investigated using Landsat normalized difference vegetation index (NDVI) data. Analyses of several indicators, including changes in NDVI in different slopes and land use changes and the relationships between climatic factors and NDVI change, were presented to quantitatively evaluate the effects of agriculture, climate, and policy on NDVI change. The NDVI in the Zuli River Basin increased during the study period, and the main contributors to this change were forest in 1999–2011, cropland, abandoned farmland, and grassland in 2009–2016, and land with slopes ≤ 15°. Land with slope > 15°, where the “Project” was implemented, slightly contributed to the increase in regional NDVI. In 1999–2011, the project (?98.16%) combined with climate change (?68.18%) showed negative effects on the increase in NDVI in the Zuli River Basin, but agriculture (22.28%) played a positive role in increasing this index. In 2009–2016 and 1999–2016, the project (38.45% and 35.25%, respectively), the project combined with climate change (49.83% and 46.30%, respectively), agriculture (18.61% and 23.30%, respectively), promoted increases in NDVI in the basin.  相似文献   
27.
随着武汉周边地区城镇化、经济发展和人民生活水平的提高,农业生产工业化水平日渐提高,武汉周边地区农村生态环境也日益恶化.对加强农业生态环境保护措施进行了探讨.  相似文献   
28.
从多个角度对邯郸市农业现状进行了研究分析.认为邯郸市农业总体可持续发展水平有所加强,但也存在一些问题.根据实际情况,提出一些合理化建议.  相似文献   
29.
Agricultural systems with grazing animals are increasingly under scrutiny for their contribution to quality degradation of waterways and water bodies. Soil type, climate, animal type and nitrogen (N) fertilisation are contributors to the variation in N that is leached through the soil profile into ground and surface water. It is difficult to explore the effect of these factors using experimentation only and modelling is proposed as an alternative. An agro-ecosystem model, EcoMod, was used to quantify the pastoral ecosystem responses to situational variability in climate and soil, choice of animal type and N fertilisation level within the Lake Taupo region of New Zealand. Factorial combinations of soil type (Oruanui and Waipahihi), climate (low, moderate and high rainfall), animal type (sheep, beef and dairy) and N fertilisation level (0 or 60 kg N/ha/yr) were simulated. High rainfall climates also had colder temperatures, grew less pasture and carried fewer animals overall which lead to less dung and urinary N returned. Therefore, even though a higher proportion of N returned ultimately leached at the higher rainfall sites, the total N leached did not differ greatly between sites. Weather variation between years had a marked influence on N leaching within a site, due to the timing and magnitude of rainfall events. In this region, for these two highly permeable soil types, N applied as fertiliser had a high propensity to leach, either after being taken up by plants, grazed and returned to the soil as dung and urine, or due to direct flow through the soil profile. Soil type had a considerable effect on N leaching risk, the timing of N leaching and mean pasture production. Nitrogen leaching was greatest from beef cattle, followed by dairy and sheep with the level of leaching related to urine deposition patterns for each animal type and due to the amount of N returned to the soil as excreta. Simulation results indicate that sheep farming systems with limited fertiliser N inputs will reduce N leaching from farms in the Lake Taupo catchment.  相似文献   
30.
高邮市丘陵山区农业综合开发项目于2000年正式立项实施。10年来,实施总面积1346.67hm2,项目区涉及送桥、菱塘、天山、郭集4个乡镇24个行政村(场)。项目的成功建设,加快了高邮市丘陵山区的发展,促进了农业增效、农民增收和农村繁荣。  相似文献   
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