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41.
我国农林机器人的研究现状及发展趋势   总被引:1,自引:2,他引:1  
机器人作为高科技的产物在世界各国得到了迅猛的发展。农林业机器人是 2 1世纪我国林业和农业机械的发展方向。本文综述了我国林业和农业机器人的研究现状 ,介绍了几种典型的机器人。  相似文献   
42.
中国是一个具有生物地理多样性和复杂社会经济条件的大国,其农林业资源的可持续性正在受到变化的自然和社会经济环境的严峻挑战。分析表明,多样化的农林复合系统(Agroforestrysystems)在中国各主要区域可持续农业发展中起着十分重要的作用。然而,适用于多样化的农林复合系统综合评价方法的缺陷,使农林复合系统具有的优势难以得到真实的反映。文章从单一目标评价、多目标评价、风险评价和社会经济评价四个方面,分析了其在中国农林复合系统评价中的应用。分析显示中国农林复合系统的评价主要局限于财务效益方法。从农业可持续发展的宏观背景出发,这显然是不够的。文章接着探讨了在人类生态学理论的基本框架中,农业生态系统分析方法、农业系统分析方法及农林复合系统设计与诊断方法在农林复合系统评价中综合运用的可能性。并指出模型方法,特别是多目标规划方法,由于其与农林复合系统多功能特性一致,具有很大应用潜力。文章最后给出了农林复合系统综合评价的理论构架,指出农林复合系统是个特殊的具有多层次、多功能和多效益特征的农业生态系统。农林复合系统的综合评价必须从可持续发展的观点出发,设计和选择包括生态、经济和社会文化方面的多目标标准体系,并在不同层次  相似文献   
43.
通过对贵州省晴隆县紫马乡退耕还林的调查研究,分析了目前在经济补偿政策中出现的补偿标准不合理,后续管护存在"漏补"现象、补偿年限非持续性,存在复耕隐患、补偿资金融资渠道单一,投入产出错位、补构偿政策执行有偏差等问题.提出了调整补偿标准、延长补偿期限、建立多层次的经济补偿制度等政策建议.  相似文献   
44.
Population pressure, expansion of small-scale agriculture and shifting cultivation are commonly cited as the causes of tropical deforestation. A close examination of deforestation and agriculture in the Philippine uplands reveals, however, that the vast majority of agriculturists must be sedentary farmers. In addition, the importance of population pressure as a cause of deforestation in the Philippines cannot be supported by the available evidence. Lastly, the concept of arable land is shown to be of limited value in discussing upland agriculture in the Philippines.  相似文献   
45.
根据低山丘陵区的特点,因地制宜地实行农、林、果、牧等生物措施与工程措施相结合,充分发挥当地的资源优势,建立良性的生态农业结构,取得短期的经济效益,是开发低山丘陵区的有效途径。  相似文献   
46.
通过论述效益农(林)业特征和作用的基础上,围绕浙江山区效益农(林)业的三种主要类型(龙头企业带动型,特色品牌型,生态观光型)进行剖析。同时在分析浙江山区效益农(林)业存在的问题的基础上,提出了发展效益农(林)业的目标和对策。  相似文献   
47.
Field runoff plots, 70 x 10 m each, were established on a tropical Alifisol in southwestern Nigeria to monitor water runoff, soil erosion and nutrient loss in water runoff. The non-agroforestry control treatment (A) was established at two levels: plow-till and no-till systems of seedbed preparation. There were two agroforestry systems based on contour hedgerows of (B) Leucaena leucocephala and (C) Gliricidia sepium established at 4-m and 2-m spacings. Field plots were established in 1982 and hydrological measurements were made for uniform maize-cowpea rotation for 12 consecutive growing seasons from 1982 through 1987. Once established hedgerows of Leucaena at 2-m spacing were extremely effective in reducing water runoff and controlling erosion. Runoff, erosion and nutrient losses were generally more from maize grown in the first season than from cowpea grown in the second. Mean seasonal erosion from maize was 4.3, 0.10, 0.57, 0.10, 0.64 and 0.60 t/ha for plow-till, no-till, Leucaena-4m, Leucaena-2m, Gliricidia-2m treatments, respectively. Mean runoff in the first season from treatments listed in the order above was 17.0, 1.3, 4.9, 3.3, 4.3, and 2.4 percent of the rainfall received. There were high losses of Ca and K in water runoff from the plow-till treatment. In contrast to runoff and erosion, losses of bases in water runoff from agroforestry treatments were relatively high, high concentration of bases in runoff was probably due to nutrient recycling by the deep-rooted perennials.  相似文献   
48.
刘熠 《长江蔬菜》2015,(20):35-38
从我国设施蔬菜的发展现状出发,针对生产型农业园区的规划理念、市场定位、近远期规划方向、功能分区、分项规划、规划保障等方面均进行了研究,对于生产型农业园区近期应具备的各项功能区进行了进一步的阐述与研究,同时针对设施蔬菜现代农业园区的远期建设模式进行了阐述。  相似文献   
49.
An analogue approach to analysing the traditional homegardens of Keralavis-à-vis natural climax ecosystems is adopted. The traditional homegarden is apparently a climax ecosystem, where ecological succession is consciously manipulated by human beings. High intensity of vertical and horizontal space use, the highly dynamic chronological structure and the capacity to perform essential ecological processes make this ecosystem relatively sustainable. Homegardens in Kerala effectively serve as human ecosystems with their low input demand, staggered supply of outputs, and enhancement of habitat quality. However, recent trends in agrarian structure and the high market orientation exert pressures on the homegarden, and its sustainability as a human ecosystem is in question.This joint paper is based on part of the research conducted by Darley Jose for the degree of M.Sc. (Natural Resource Management) at the Agricultural University of Norway under the guidance of N. Shanmugaratnam.  相似文献   
50.
The Rwandan farmers, faced with a perpetual land shortage, have evolved certain intensive systems of organic agriculture. These systems, particularly the homestead (compound) farming, involve the combination of food, fodder and tree crops. to a certain extent these systems can satisfy the multiple needs of the subsistence farmers living under several risks and constraints. However, they cannot cope with the expanding food demand of the rapidly increasing population. Some multipurpose, low-input technologies and agroforestry approaches have been designed to improve the productivity of these traditional systems; these include inter/mixed cropping systems and rotations, alley cropping with leguminous trees and shrubs, use of planted fallow, planting tree legumes on anti-erosive lines, mixed farming,community forestry and woodlots, and tree planting on farm/field boundaries. The essential aspects of these technologies are briefly discussed.ISAR-IITA FSR PROJECT, B.P. 629, Kigali RwandaISAR-Swiss Intercooperation, c/o Forestry Department, B.P. 617, Butare, Rwanda  相似文献   
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