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41.
将系统分析原理和数学建模技术应用于紫苏栽培管理知识表达体系,通过解析和提炼紫苏生育指标及栽培技术与生态环境和生产技术水平之间的基础性关系和定量化算法,构建了具有时空规律的紫苏栽培管理动态知识模型,并进一步利用软件技术在Visual C++平台上构建了基于知识模型的紫苏管理决策支持系统(KMDSSPM),实现了不同环境条件下的紫苏播前栽培方案设计及产中调控指标预测。其中,播前方案设计包括产量目标与产量结构、密度设计、移栽方案、肥料运筹及水分管理等;调控指标预测包括叶龄动态,叶面积指数动态和干物质积累动态等。紫苏栽培管理知识模型的建立,克服了传统紫苏栽培模式及专家系统地域性强和广适性差的不足,从而为实现紫苏栽培管理决策的定量化和数字化奠定了基础。 相似文献
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基于模糊环境下具有监督因子的目标函数,提出了计算最优模糊关系识别决策矩阵和目标权重的优化模型,进一步完善了模糊关系优选理论模型;并应用于农业耕作方式的模糊优选,取得了满意的效果。 相似文献
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为探讨水稻主栽品种病虫侵害风险和综合抗性,采用田间多点自然诱发法对杭州地区11 个水稻主栽品种的主要病虫害抗性进行综合评价。结果表明,应用多目标综合评价和决策方法,对田间主要病虫的综合抗性强弱排序为:‘甬优538’>‘甬优12 号’>‘秀水134’>‘甬优15 号’>‘浙优18 号’>‘丰两优香1号’>‘甬优8 号’>‘甬优9 号’>‘中浙优1 号’>‘中浙优8 号’>‘天优华占’,表现为高抗、中抗的品种分别为4 个、5 个,中感、高感各1 个;2 个试验点在褐飞虱、白背飞虱、稻纵卷叶螟、纹枯病等当年田间发生量大的病虫抗性分析结果较一致,而零星发生的病虫上表现的抗感程度有差异。经多目标决策法分辨各目标性质并作相应变换,两地各品种的总体抗性评价排序较一致,父本亲缘关系相近的水稻品种具有相近的综合抗性。根据品种结构与抗性变化制定综合防治策略,可为不同品种布局下的病虫害监测预警和防控提供依据。 相似文献
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《Human Dimensions of Wildlife》2012,17(6):515-532
ABSTRACTAs long as the funding mechanism supporting state wildlife conservation relies heavily on hunter-generated funds, declines in hunter participation are a threat to the conservation of both game and nongame species. To address options to bolster wildlife agency profit from the sale of hunting licenses, we developed a stage-based, stochastic population model of a hunter population, and demonstrate its utility within a decision-making framework to inform state wildlife agency decisions. We evaluated hypothetical youth and adult recruitment-focused outreach programs over 10 years to increase license sale profit. Using our model as the core of a decision analysis, state agencies can set hunter population or license profit targets, and evaluate management actions designed to achieve those objectives. We expect that our approach will provide a valuable framework for anticipating the future of hunting and hunting-generated conservation funds, and can be extended to other user groups, including target shooters and anglers. 相似文献
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《Human Dimensions of Wildlife》2012,17(1):70-82
Abstract Fish and wildlife management in North America has been experiencing a fundamental philosophical shift among professional managers and policy makers about who are the beneficiaries of management. This has been reflected in broadening notions of who should be considered in decision making; not just traditional clients who pay for and receive services of managers, but all stakeholders in fish and wildlife management. The term “stakeholder”; has emerged to represent any citizen potentially affected by or having a vested interest (a stake) in an issue, program, action or decision leading to an action. The stakeholder approach in management decision making recognizes a larger set of beneficiaries of management (including, in concept, future generations) than the traditional concepts of constituencies and clients, or customers, a term currently popular among fish and wildlife agencies. The stakeholder approach requires: (1) identification of important stakeholders, (2) flexibility in selection of methods for incorporating stakeholder input in decision making to account for specific contexts, (3) development of a professional management philosophy strong enough to resist powerful special interests when broader public interests are in the balance, (4) development of ways to weigh stakeholder views on issues in management decision making, and (5) establishment of effective strategies for communication between managers and stakeholders and among stakeholders to encourage understanding and compromise. 相似文献
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《Human Dimensions of Wildlife》2012,17(4):22-39
Abstract Voters are unlikely to be guided by a systematic assessment of information regarding the consequences of wildlife ballot initiatives; the time investment is too high and the topic involvement is too low. Instead, they form heuristics or decision rules to guide their behavior. Heuristics are formed from a subset of available information that triggers general attitudes or basic beliefs that are already formed and easily accessible to the individual. Guided by this explanation, a telephone survey was used to determine the basis for voting behavior on a Colorado ballot initiative to ban steel‐jawed traps and snares that passed in November 1996. Open‐ended, thought‐listing procedures were used in asking voters why they voted their stated position. A high proportion of people listed few beliefs associated with their voting behavior, a finding more prevalent with yes‐voters, (those in favor of banning trapping) than no‐voters (those against a ban on trapping). While the substance of beliefs listed by no‐voters was diffuse, a preponderance of yes‐voters cited a belief that trapping is cruel and inhumane. Beliefs about voting were strongly associated with one's basic value orientation. Findings are consistent with the consequences of heuristic processing. Results suggest that those wishing to influence voting behavior on wildlife ballot initiatives should provide persuasive messages that introduce simple decision rules that are closely aligned with more basic attitudes. Findings also highlight the limitations of ballot initiatives that lead to decisions made in lieu of careful deliberation of consequences. 相似文献
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森林可持续经营实践若干问题的思考 总被引:5,自引:4,他引:5
森林可持续经营实践已在国内外开展并逐步走向深入,而从我国森林可持续经营实践来看,仍有许多问题值得我们去思考,研究和解决:(1)政策支持体系问题,从中观和微观操作水平探讨与森林可持续经营相协调的各类政策。(2)实证研究问题,从具体的历史事实和案例中寻找森林可持续经营的一般规律,并进行理论创新。(3)决策过程和方法问题,探讨“自上而下”的决策过程,理顺农民,科技人员和政府的多方参与关系和各自承担的角色。(4)利益结构的调整和优化问题,调整和优化森林可持续经营中不同主体之间的利益结构,研究和设计确保森林经营者利益的政策。参4。 相似文献
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