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101.
城市绿化中大树反季节移植技术 总被引:8,自引:0,他引:8
阐述了大树反季节移植在城市绿化中的重要作用,以及影响大树移植成活的原因。提出了提高大树反季节移植成活率的技术措施。 相似文献
102.
Participatory mapping and GIS are both necessary to model the interactions between humans and their environment. A case study
from the forest margin in the Congo Basin demonstrates how data from participatory community mapping and other social science
methods can be prepared for quantitative modelling. This approach bridged the gap between spatial modelling data and social
decision-making in space by elaborating a geographically consistent social representation of the landscape and giving a geographical
base to the connection between land use, its cultural representation, and its social management. This was achieved through
an iterative process of GIS cartography, using feedback from village informants and field checking, to transpose the spatial
references from participatory mapping sketches into reliable geographic locations. As well as demonstrating the utility of
such data for modelling, this work clarified the distribution of land rights among the six main owner-clans spread through
the eight hamlets in the watershed. The ‘basin’ of spatial resources and its relation to the rules of land use and natural
resource management were defined for each clan. Land-use systems at the forest-agriculture interface in the study area proved
to be complex, strongly driven by social rules and influenced by history and settlement strategies. These social and historical
aspects established the framework within which communities make current decisions and interventions.
The authors thank the people of Akok for their collaboration and hospitality. Village technician Michel Engueng and village
contact Adolphe Ze facilitated and assisted this work. Our thanks also to Julie Mbazo’o and Remy Assoumou, both members of
the ‘social side’ working group of the FLORES modelling team. Christopher Legg’s contribution to the discussion of this work
through his constant reviewing of the CamFlores model is gratefully recognized. Finally, thanks to the whole CIFOR-ACM team
for numerous scientific and methodological inputs. The Italian Foreign Ministry funded the work of Valentina Robiglio (APO-GIS
specialist) through an APO contract with IITA. The European Union (Tropical Forestry budget line DG VIII) contributed to the
CIFOR’s research program on the ‘Adaptive Collaborative Management of Forests’ (ACM) in Africa, and to the Alternative to
Slash and Burn (ASB) program in Cameroon on ‘Environmental Services and Rural Livelihoods’ through the World Agroforestry
Centre. 相似文献
103.
机器人逆运动学在机器人学中占有非常重要的地位。为此,建立了COMAU-120机器人的运动学模型,并利用奇次变换导出了逆运动学求解公式。机器人逆运动学分析方法在实际中得到了应用,为实现弧焊机器人系统路径规划和离线编程奠定了基础。 相似文献
104.
105.
Remotely sensed (RS) data is a major source to obtain spatialdata required for hydrological models. The challenge for thefuture is to obtain besides the more direct observable data(landcover, leaf area index, digital elevation model andevapotranspiration), non-visible data such as soilcharacteristics, groundwater depth and irrigation practices.In this study we have explore the option of using inversemodeling to obtain these non-RS-visible data. For a commandarea in Haryana, India, we applied for the 2000–2001 rabiseason a RS-GIS-combined inverse modeling approach to derivenon-RS-visible data required in the regional application ofhydrological models. A Genetic Algorithm loaded stochasticphysically based soil-water-atmosphere-plant model (SWAP) wasdeveloped for the inverse problem and used in the study. Theresults showed good agreement with the inventoried data suchas soil hydraulic properties, sowing dates, groundwaterdepths, irrigation practices and water quality. The deriveddata could be used to predict the state of the system at anytime in the cropping season, which can be used to evaluateoperational management strategies. 相似文献
106.
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108.
甜玉米小斑病抗性的遗传分析与主效QTL定位 总被引:1,自引:0,他引:1
为培育抗病品种,利用抗小斑病甜玉米自交系T14和感小斑病自交系T18为亲本配制杂交组合,对玉米抗小斑病性状进行遗传分析和抗病基因分子标记定位,用主基因+多基因混合遗传模型和P1、P2、F1、B1、B2、F2 6世代联合分析的方法对单位叶面积病斑数量进行遗传分析,并应用复合区间作图法检测抗小斑病QTL。结果表明,单位叶面积病斑数量受2对加性-显性-上位性主基因控制,自交系T14的抗病性在各个分离世代都以主基因遗传为主。在第4染色体上检测到4个相互连锁的小斑病抗性QTL,解释表型变异的7.7%、30.9%、14.8%和11.5%;在第6染色体上定位了1个抗病QTL,可解释表型变异的37.7%。检测到的小斑病抗性主效QTL位于第4和第6染色体的特征与2对主基因的遗传模型相吻合。 相似文献
109.
为明确抗锈品种中梁93444抗条锈基因及遗传特点,用CYR30、CYR31、CYR32对该品种、铭贤169及杂交组合进行遗传分析,用SSR技术对分离家系F3-3进行PCR扩增和电泳分析。结果显示,中梁93444对CYR30、CYR31的抗病性均由1对显性和1对隐性基因控制,对CYR32由2对显性互补基因控制;F3-3分离家系对CYR32的抗病性由1对显性基因控制,该基因暂命名为Yr93444。对F3-3分离群体进行SSR标记,建立了与该基因连锁的8个标记Xgwm122、Xwmc702、Xwmc644、Xwmc794、Xgwm328、Xwmc455、Xgwm372、Xwmc819,遗传距离分别为38.1、30.7、22.9、15.6、10.0、6.9、3.5和2.8 cM。 应用SSR标记、中国春及缺四体将Yr93444定位于2AL上。系谱分析和SSR分子标记检测表明,该基因是来自中间偃麦草的新抗条锈基因。用与该基因紧密连锁的SSR标记Xgwm372和Xwmc819检测中梁品种和黄淮麦区主栽品种,发现89%中梁品种含该抗病基因,而86%黄淮麦区主栽品种不含该抗病基因,表明该基因应用潜力很大。 相似文献
110.
从研究应用背景、基础理论及模型、实验模拟等方面就微咸水灌溉过程,侵入界面土壤渗透性变化进行分析研究.以衡水典型研究区微咸水分布及水质矿化度分析数据为基础,应用地球化学模式PHREEQC,结合水敏性机理分析矿物迁移的存在形式及各种形式之间的转化关系.结果表明:含高价离子农灌微咸水加快粘土胶体颗粒絮凝沉降能力强于低价离子,... 相似文献