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971.
国外城市农业景观(Urban Agriculture Landscape)案例评析 总被引:1,自引:0,他引:1
从城市农业概念界定、国外城市农业景观实践与案例启示三个部分,对国外城市农业景观的指导原则、发展策略、设计方法进行解读,以期在社会学意义、生态学功能等层面上为中国高速城市化进程中开放空间的规划与绿色基础设施建设提供深度参照。文章认为景观正成为对城市空间碎片进行生态整合的主要媒介之一,城市农业在城市生态与城市形态、食品安全与食物供给、自然教育与工作机会等诸多方面有着巨大潜力,可以作为构建现代可持续发展城市的路径之一。 相似文献
972.
Rapid urbanization and spontaneous economic development has brought about profound changes in urban landscapes throughout the world. The task of managing transforming urban landscapes, particularly urban green spaces, so as to provide sufficient natural amenity for increasing urban populations, is one of the critical challenges facing policy makers. However, little empirical evidence exists about the evolving path of urban green spaces along with economic development and urbanization. This study attempts to fill in this knowledge gap through an econometric analysis of panel data across 285 Chinese cities during a period of rapid urbanization and economic growth (2001–2010). The results point to the existence of an N-shaped environmental Kuznets curve (EKC) for an important aspect of environmental quality: urban green spaces. Urban green space coverage increases at the initial stage of economic development, and then it starts to decrease as GDP per capita exceeds RMB50,855 and then increases again at a high GDP per capita level (RMB107,558). Large elasticity (>1) is expected as GDP per capita grows to a higher level (beyond RMB128,095). By the end of 2010, 30% of Chinese cities are still located on the downward-sloping path and only four cities have attained elasticities greater than one. The findings present a challenging and pressing call for policy makers to effectively manage the tradeoffs between continuous economic development and better natural amenities. 相似文献
973.
Jun Qin Xin Zhou Chanjuan Sun Hanbing Leng Zhiwei Lian 《Urban Forestry & Urban Greening》2013,12(4):490-497
Influence of urban green spaces on human was evaluated with subjective questionnaires as well as physiological measurements. Five sample plots vary in color, size and scent of major plants and one no-vegetation area located in Shanghai Botanical Garden, China were chosen. 249 questionnaires on subjective satisfaction evaluation were collected; in addition to 64 visitors took the measurement of physiological parameters like Electroencephalogram (EEG) and Electrocardiogram (ECG). Questionnaire results show that color is one of the most important factors which affect the overall satisfaction of people with their vegetation environment. The way how people perceive vegetation environment was probed by PCA analysis. Age difference analysis show children and elder people presented higher satisfaction with vegetation environment than adults. Significant negative correlation between the ratio of low-frequency to high-frequency (LF/HF) values in heart rate variability (HRV) analysis and satisfaction values indicated HRV may be an effective parameter for green spaces influence evaluation. 相似文献
974.
S. Muñoz-Vallés J. Cambrollé E. Figueroa-Luque T. Luque F.X. Niell M.E. Figueroa 《Urban Forestry & Urban Greening》2013,12(4):450-453
The maintenance and improvement of current natural carbon sinks, as well as the creation of others, are presently considered among the main strategies by which to address global climate change, and are pursued in parallel to the implementation of policies of carbon emission reduction. To date, this approach has been applied mainly to forest areas, obtaining relevant results that help to identify areas of weakness in the strategy and to design appropriate management measures. Nevertheless, under the current situation, and at territorial level, urban areas and infrastructures, in which urban green systems play a significant role, present opportunities for contributing towards carbon sink potential. Various studies conducted by our research group have emphasized the role of urban green systems as natural carbon sinks, including research conducted under initiatives from European authorities (“Climeport project/Mediterranean Ports’ Contribution to Climate Change”), regional government (Andalusian Strategy against Global Climate Change) and Andalusian universities (Andalusian University Rectors Climate Change Pact). Through these projects, we have assessed entire systems, identifying the species of urban trees and shrubs with the greatest sink potential under different climate scenarios, proposing garden management schemes, and providing a basis for the creation, design, management and improvement of natural carbon sinks in the cities. 相似文献
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978.
绿色农业是21世纪的农业发展方向,以往对绿色农业的研究大多只采用了定性方法。本文将经济学中的博弈论引入发展绿色农业的探讨,通过对绿色农业发展初期政府与农户的博弈研究,即地方政府吸引农户发展绿色农业以及政府确定发展绿色农业的农户资格的博弈两方面进行博弈分析,得到一些有益的结论。 相似文献
979.
为了客观地评价不同主产地绿茶品质的差异性,统计分析了四川、湖北、福建的16个绿茶样品的茶多酚、茶多糖、茶氨酸、灰分、水分、重金属、农药残留含量的差异。结果表明,四川产绿茶的茶氨酸含量显著高于湖北,3个省份的茶多酚、茶多糖含量差异不显著;茶多酚、茶多糖、茶氨酸含量最高的产地分别为宜宾市、峨眉山市、眉山市(编号3)。湖北产绿茶的灰分含量显著高于四川和福建,水分含量显著低于四川;不同主产地绿茶的重金属含量和农药残留量均符合食品安全国家标准。研究结果将为绿茶原料的产地选择、品质评价等提供技术依据。 相似文献
980.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2975-2994
Soil organic matter (SOM) is an essential ecosystem component whose dynamics are affected by soil management practices. To evaluate the impact of two agricultural systems (organic and conventional) on soil organic carbon (C) and nitrogen (N) stocks in a sandy soil, samples were collected from the Amway Nutrilite Brazil farm and from the Central Pivot Horticultural Farmers Association farm, both situated in the Chapada da Ibiapaba region, Ceará State, Brazil. The first area has a large‐scale Caribbean Cherry fruit production system under organic management, whereas the second represented a conventional soil cultivation condition, characterized by the use of chisel plow and disc plow, mineral fertilization, and herbicides application. Plots with and without green manure fertilization were compared in the organically cultivated systems by using soil samples collected in the rows and between the rows. Areas under native forest were also sampled to determine the steady‐state condition. Total organic C and N contents in the soil (SOC, TN) and in the humic substances were determined at the 0‐ to 5‐, 5‐ to 15‐, 15‐ to 30‐, and 30‐ to 50‐cm soil layers. In addition, oxidizible organic C fractions were measured to calculate the carbon management index (CMI). In general, total SOC levels were low, ranging from 2.5 to 12.6 g kg?1 in the whole soil profile among the organic systems. In the upper soil layer, SOC and TN stocks were greater in the rows in response to organic fertilization. The conventional system presented lower variation on the SOC contents throughout soil layers when compared to the native forest area, indicating the direct effect of plowing on the downward SOC distribution. The CMI data confirmed the reestablishment of SOM levels in the rows of the organic managed systems in relation to the reference area, whereas the reduction of the CMI in the conventional system suggests a decline in the soil quality and greater potential for increased C losses to the atmosphere. 相似文献