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961.
许昌市休闲绿地土壤肥力特征研究 总被引:2,自引:0,他引:2
以许昌市休闲绿地表层土壤为研究对象,在野外采样和室内分析的基础上,对其土壤肥力特征进行研究,以期为城市绿地土壤养分研究及管理提供参考。结果表明,许昌市休闲绿地表层土壤速效氮含量为12.55~176.44mg/kg,均值54.74mg/kg,整体上属于土壤养分分级的5~6级;速效磷含量为4.61~76.86mg/kg,均值32.18mg/kg,整体上为3级及其以上;速效钾含量为177.36~477.54mg/kg,均值324.23mg/kg,整体上属于1级;土壤有机质含量为16.48~78.87g/kg,均值40.67g/kg,整体上为2级及其以上;土壤综合肥力指数为1.29,属于三等土壤,肥力水平一般。因此建议,许昌市休闲绿地应多栽植绿肥植物;增施氮肥以均衡养分提高土壤肥力水平,增施有机肥以平衡土壤酸碱度改善土壤质量。 相似文献
962.
黄山毛峰茶连续化生产线加工工艺参数的研究 总被引:1,自引:0,他引:1
为提高黄山毛峰茶连续化加工质量,研制自动化加工控制系统,采用新型国产化的茶叶品质分级仪对茶鲜叶质量进行分等,通过对其生产线上在制品的含水率、加工耗时及叶温的检测与分析,制定合理的加工工艺参数。试验结果显示,以特级、一级、二级、三级茶鲜叶为研究对象,喂料机皮带秤流量分别为160、210、250和230 kg.h-1,滚筒电流输出值分别为60%、80%、100%和90%,滚筒转速分别为24、24、26和28 r.min-1。利用高温数据采集仪检测了杀青、烘干过程的叶温变化,得到烘干过程的叶温测定结果与烘干机温控设定值大致相同。结果表明,采用高温数据采集仪在线监测在制品温度是可行的。 相似文献
963.
964.
通过2a田间定位试验,研究渭北旱塬地区夏闲期插播并翻压不同豆科绿肥(长武怀豆、大豆和绿豆)以及小麦生长季不同施氮量(0,108,135,162 kg/hm2)对麦田土壤肥力性状的影响,以期为提高旱地土壤质量提供理论依据.试验结果表明:(1)种植豆科绿肥能显著提高土壤有机质、活性有机质和全氮含量,增加土壤碳库管理指数(CPMI),对土壤速效钾含量没有显著影响;(2)绿豆还田量高于长武怀豆和大豆,然而土壤培肥效果逊于长武怀豆和大豆;(3)夏闲期种植绿肥明显消耗了土壤水分,导致绿肥翻压前、小麦播前直至收获后,0-200 cm土壤贮水量显著低于休闲处理,但耗水量与休闲没有明显差异,由于小麦产量显著增加,因此豆科绿肥显著提高了水分生产效率;(4)与不施氮相比,小麦生长季施用氮肥能显著增加土壤水分生产效率,却对土壤各肥力性状的影响均不显著.夏闲期种植并翻压豆科绿肥是旱地培肥土壤、提高水分生产效率的有效途径. 相似文献
965.
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
966.
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
967.
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
968.
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
969.
970.