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341.
采用CLGIS软件的测井资料由于其输出格式及种类的局限性限制,不能同时把测井成果图做在一张图纸上.为此利用Corel DRAW平面设计软件中的VISUAL basic语言编制了测井曲线绘制程序,解决了clgis出图单一的问题,并且可以将勘探线剖面上的多条测井曲线绘制于一张图上。具有操作简单,易学,制图速度快,使用灵活等特点,在吉林省重点勘探项目上得以应用,取得好的效果,受到地质报告评审专家们的好评。  相似文献   
342.
This article addresses the question of how forestry projects, given the recently improved standards for the accounting of carbon sequestration, can benefit from existing and emerging carbon markets in the world. For a long time, forestry projects have been set up for the purpose of generating carbon credits. They were surrounded by uncertainties about the permanence of carbon sequestration in trees, potential replacement of deforestation due to projects (leakage), and how and what to measure as sequestered carbon. Through experience with Joint Implementation (JI) and Clean Development Mechanism (CDM) forestry projects, albeit limited, and with forestry projects in voluntary carbon markets, considerable improvements have been made with accounting of carbon sequestration in forests, resulting in a more solid basis for carbon credit trading. The scope of selling these credits exists both in compliance markets, although currently with strong limitations, and in voluntary markets for offsetting emissions with carbon credits. Improved carbon accounting methods for forestry investments can also enhance the scope for forestry in the Nationally Determined Contributions (NDCs) that countries must prepare under the Paris Agreement.

POLICY RELEVANCE

This article identifies how forestry projects can contribute to climate change mitigation. Forestry projects have addressed a number of challenges, like reforestation, afforestation on degraded lands, and long-term sustainable forest management. An interesting new option for forestry carbon projects could be the NDCs under the Paris Agreement in December 2015. Initially, under CDM and JI, the number of forestry projects was far below that for renewable energy projects. With the adoption of the Paris Agreement, both developed and developing countries have agreed on NDCs for country-specific measures on climate change mitigation, and increased the need for investing in new measures. Over the years, considerable experience has been built up with forestry projects that fix CO2 over a long-term period. Accounting rules are nowadays at a sufficient level for the large potential of forestry projects to deliver a reliable, additional contribution towards reducing or halting emissions from deforestation and forest degradation activities worldwide.  相似文献   

343.
This article uses research about non-timber forest products (NTFP) gathering in Seattle, Washington, USA to examine how people gain access to natural resources in urban environments. Our analysis focuses on gathering in three spaces: parks, yards, and public rights of way. We present a framework for conceptualizing access, and highlight cognitive mechanisms of access associated with foragers’ internal moral judgments about harvesting. Key findings are: (1) internal moral calculations about whether it is right or wrong to harvest a particular NTFP in a particular place are an important but previously unacknowledged mechanism governing resource access; and (2) these calculations may help prevent over-harvesting of NTFPs, which are common pool resources, in urban environments where social and environmental conditions lend themselves to a de facto situation of open access. Our findings suggest that voluntary codes of conduct may be the best way to manage NTFP access in cities.  相似文献   
344.
阿拉善盟梭梭苁蓉开发利用成为地区重点产业化建设工程   总被引:2,自引:1,他引:1  
李克云  杨永奇 《中国沙漠》2002,22(5):510-512
通过20世纪50年代、80年代及2002年阿拉善地区梭梭林资源对比说明,梭梭林呈现严重退化发展趋势。原因在于长期超载过牧及人类不合理开发利用和气候干旱等原因。肉苁蓉也在随之退化消失,针对这种情况,各级党政部门将梭梭林保护及肉苁蓉培育开发利用作为全盟产业化重点工程,采取退牧还林、围栏封育、人工种植、依法保护管理、加大技术推广和科研开发等措施,建立阿拉善乃至西部地区最大的产业基地,添补国际市场对肉苁蓉的需求。  相似文献   
345.
内蒙古准格尔旗丘陵沟壑区退耕还林(草)模式   总被引:2,自引:0,他引:2  
根据准格尔旗的自然环境特点,社会经济状况,以及水土流失及沙漠化灾害的特点,总结出适用上述条件下的退耕还林(草)的几种模式,恢复生态,发展经济。  相似文献   
346.
元坝区块提高钻井速度技术方案探析   总被引:2,自引:0,他引:2       下载免费PDF全文
在总结分析前期钻井经验的基础上,从地质因素、钻井复杂情况、岩石可钻性、地层温度、钻井液密度、井身结构等方面分析了目前影响元坝区块深井钻井速度提高的因素。指出井身结构层次有限,不能完全有效封隔不同压力体系的地层以及须家河组地层可钻性差、埋深较深、段长,不能利用空气钻进行钻进是影响机械钻速的2个最重要原因。提出了气体钻井方案、钻头选型方案、进口动力钻具配合高效钻头钻须家河地层方案,以及采用特种井眼尺寸井身结构方案,为元坝区块深井钻井提供技术支持。  相似文献   
347.
张伟 《探矿工程》2010,37(11):1-5
讨论了特深岩心钻孔钻探施工的套管程序、钻具及其级配和固井等问题,深入分析了这些技术问题对特深孔钻探施工的风险性和经济性的影响作用。在分析研究的基础上,提出了对我国施工特深岩心钻孔时的套管程序、钻具级配、特深孔钻杆柱、套管柱以及固井等技术方案的建议。  相似文献   
348.
根据测定天文大气折射的原理,叙述了利用相应的观测值获得瞬时大气折射测定值和建立大气折射实测模型的途径,并从各种测定值与最后结果之间的关系,指出了这里对数据处理的要求;文章介绍了对测定值进行波长改正和建立折射延迟实测模型的处理方法,分析了改正模型对天文大气折射测定值的分布要求,给出了观测数据随天顶距的增大而加密的分布模型。  相似文献   
349.
嵌入式软件覆盖测试的研究   总被引:5,自引:0,他引:5  
在实际应用中覆盖测试分析采用测量方法的多样性决定了代码插装需要识别程序结构特征的复杂性。结合编译原理的中间代码优化理论,针对汇编语言开发的嵌入式软件,提出了划分基本块,构造程序流图来分析汇编源程序的结构的算法模型,并讨论了覆盖测试的方法及原理。  相似文献   
350.
Ashley A. Webb 《水文研究》2009,23(12):1679-1689
Streamflows were measured in two Pinus radiata plantation catchments and one native eucalypt forest catchment in Canobolas State forest from 1999 to 2007. In 2002/2003, clearfall harvesting of 43·2 and 40·3% of two plantation catchments occurred, respectively. Water yields increased by 54 mm (52%), 71 mm (35%) and 50 mm (19%) in the first three years post‐harvest in treated catchment A and by 103 mm (118%), 157 mm (82%) and 119 mm (48%) in treated catchment B relative to the native forest control catchment. In the fourth post‐harvest water year annual rainfall was only 488 mm, which resulted in negligible run‐off in all catchments, regardless of forest cover. In both plantation catchments, monthly streamflows increased significantly (p = 0·01, p < 0·001) due to a significant increase in baseflows (p < 0·001) after harvesting. Monthly stormflows were not significantly affected by harvesting. Flow duration curve analyses indicated a variable response between the two plantation catchments. Treated catchment A was converted from an ephemeral stream flowing 42% of the time pre‐harvest to a temporary stream flowing 82% of the time post‐harvest. These changes occurred throughout all seasons of the year but were most pronounced during summer and autumn when baseflows were maintained post‐harvest but were not observed under native forest or mature pine plantations. By contrast, flow duration increased in treated catchment B from 12% of the time pre‐harvest to 38% of the time post‐harvest with the greatest changes measured during the winter and spring months when streamflow would normally occur under native forest conditions. These observations have important implications for the development of models of plantation water use to be utilized in water resource planning in Australia. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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