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41.
不同植物对煤矿废弃地土壤重金属富集转化规律   总被引:2,自引:0,他引:2  
李华娟  汤洁  张楠  李昭阳 《湖北农业科学》2014,53(16):3784-3787
于2008~2009年采取吉林省九台营城煤矿废弃地的复垦土和矸石土作为种植土壤,分别于试验小区内种植黄花草木樨(Melilotus officinalis Lam.)和紫花苜蓿(Medicago sativa L.),研究植物不同营养器官对煤矿废弃地土壤重金属的富集转化规律。结果表明,两种植物对不同土壤重金属的富集能力不同。复垦土种植条件下,黄花草木樨的叶和茎、紫花苜蓿的根和叶对Zn、Cd、Ni和Cu富集能力较强;矸石土种植条件下,黄花草木樨的叶对Ni、Cd及Cu的富集能力较强,根对Zn的富集能力较强,紫花苜蓿的叶对4种重金属的富集能力均较强,且茎对Cu和Ni、根对Zn也存在一定的富集能力。  相似文献   
42.
粉煤灰基吸附剂吸附亚甲基蓝及再生性能研究   总被引:1,自引:0,他引:1  
研究粉煤灰基吸附剂及微波辐照再生后吸附剂对亚甲基蓝的吸附行为,确定了粉煤灰基吸附剂达到吸附平衡的时间及吸附过程符合的等温吸附模型。试验结果表明,1 h后粉煤灰基吸附剂吸附基本达到平衡,吸附过程更符合Freundlich等温吸附模型,最大平衡吸附量为35.64 mg/g。对吸附饱和亚甲基蓝粉煤灰基吸附剂进行微波辐照再生研究,最佳的再生条件为微波功率700 W,再生时间2 min,粉煤灰基吸附剂再生效率为98.6%。  相似文献   
43.
结合露天石矿开采建设的实例,对露天石矿开采项目建设会产生的水土流失进行预测及危害分析,并确定了总体防治目标及防治措施布设,分析了水土流失监测重点及水土保持措施功能,总结了露天石矿开采建设项目水土保持工作中的重点。  相似文献   
44.
【目的】揭示采煤塌陷对贵州百里杜鹃林区土壤养分的影响。[方法】在选取典型对比样地的基础上,对百里杜鹃林区不同层次土壤进行了分层对比分析。【结果]结果表明,采煤塌陷后,百里杜鹃林区土壤酸性减弱,向中性趋近;土壤有机质含量有降低的趋势;土壤全量养分(全氮、全磷、全钾)含量有所提高;有效氮(铵态氮、硝态氮)含量总体提高,但速效磷、速效钾含量明显降低。[结论]采煤塌陷打破了百里杜鹃林区土壤养分的平衡,尤其是减少了有效磷、有效钾的供应。  相似文献   
45.
  1. The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales.
  2. Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future.
  3. We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public.
  4. Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing.
  5. By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.
  相似文献   
46.
在众多的数据挖掘算法中,贝叶斯算法因为准确性高,运算性能强而得到广泛应用。利用日常生活中的例子深入浅出的阐述了贝叶斯算法的基本原理,并应用SQL Server 2005数据挖掘工具,对2009年收集的农安地力评价的数据进行了分析,同时应用贝叶斯算法对地力等级进行了预测。  相似文献   
47.
Mountaintop mining with valley fills (MTM/VF) is the main source of landscape change in central Appalachia. While our knowledge of the local‐scale effects of MTM/VF on stream chemistry and biotic assemblages has recently improved, the effects at the landscape scale are less well known. In this study, we explore the effects of MTM/VF on the distributions of six fish species with contrasting ecologies in the upper Kentucky River basin, an area heavily affected by MTM/VF. Using a museum‐based data set of 239 occurrence records, land use/land cover data and boosted regression tree modelling, we were able to create robust predictive models for the focal species (AUCs = 0.82–0.93). Models explained from 41.2 to 71.9% of the variation in species distributions. We detected a marked negative influence of MTM/VF in four of the six species distribution models – with relative influences ranging from 5.9–12.7%. Species typically inhabiting faster‐flowing riffle and run mesohabitats appeared to respond more strongly to MTM/VF. Interestingly, the mean patch size of MTM/VF was more influential than the overall proportion of the watershed affected by MTM/VF in our models. Thus, our data suggest the spatial pattern of mining disturbance is very important in determining the cumulative impact of MTM/VF. Considering the central Appalachian region is a continental hot spot for freshwater biodiversity, establishing a firm understanding of the effects of MTM/VF at the landscape scale is essential if we wish to protect these natural resources.  相似文献   
48.
The success of different rehabilitation treatments following surface mining on the arid west coast of South Africa was assessed. Treatments consisting of one or a combination of topsoil addition, plant translocation and seeding were applied to experimental rehabilitation sites in 2001, while the treatment of another site in 2008 combined all three techniques. Vegetation and species cover, species richness, diversity and evenness, and grazing capacity of rehabilitation sites were sampled during winter 2009 and summer 2010, and compared with a reference site. All rehabilitated sites achieved the objective to attain a minimum grazing capacity of 20 ha per small stock unit. Rehabilitation trials were successful in establishing a vegetation cover, but were unable to return species richness and diversity to reference levels and did not resemble the reference site in species composition. Common species in reference sites were absent or only occurred in low numbers. No treatment outperformed the others and further experimentation is needed to determine the most suitable combination. It is recommended that rehabilitation should be done in multiple stages in future to improve seedling survival and to return species that are unable to establish in the adverse conditions present at the onset of rehabilitation.  相似文献   
49.
受资源结构与技术水平等多重因素的制约,煤炭资源在我国的能源供需形势中占主导地位。对山西省晋城市的煤炭储量现状和煤炭资源静态保证年限、煤炭资源需求以及煤炭供需平衡进行了分析,提出了晋城市煤炭战略储备的必要性,针对我国战略储备中存在的问题,提供了一些对策和建议。  相似文献   
50.
首先给出数据挖掘所涉及的技术领域及其研究特点,介绍了数据仓库与一般事务数据库的区别,基于对典型数据挖掘算法的基本原理、实现技术及应用领域的分析,论证了数据挖掘是当前信息技术的一个核心研究内容。文章的最后给出了未来数据挖掘的研究方向及发展趋势。  相似文献   
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