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针对电视气象节目中图片素材的选用,总结了静态图片素材的选择和运用中需要注意的问题。认为编辑人员的思想素质和审美意识高低会直接影响到电视天气预报节目的质量,适当运用美学知识,能够使节目的观赏性大大增强。 相似文献
243.
Through a critique of existing regeneration literatures the paper points to the close relationship between regeneration and sustainable development. It suggests that the economic aspects of sustainable development have tended to dominate: leading to the neglect of nature in both regeneration and sustainable development, with regeneration having a principal focus on socio-economic issues in urban settings. To address these lacunae we suggest the need for a more environmentally sensitive regeneration theory. Using this approach the paper draws on recent in-depth research in three post-industrial coalfield areas where regeneration processes operate in the form of community forest projects. It provides a critical perspective on these regeneration processes, integrating theory with empirical data and highlighting how nature is drawn into broader economic and social processes of regeneration. In conclusion, using forestry initiatives as examples, we reflect on the conceptual dissonance apparent in regeneration theory and practice, and point to theoretical insights that could enable a more critical regeneration theory; more beneficial outcomes to regeneration processes; and an improved understanding of the relations between nature, capital and community in regeneration processes and sustainable development. 相似文献
244.
Jerry M. Bernard 《国际泥沙研究》2000,(2)
lINTRODUCTIONWeoftenhavethepercepti0nthatsedimentisthebr0wnishoryell0wishcoloringinrunoffwater,thatlooksunpleasant,buteventually"g0esaway,"downstream,unseen.Butsedimentisn0tonlyaestheticallyunpleasant,itisalsoacarrierofpotentialchemicalc0ntaminants,fillsupwaterb0dies,andcausesphysicaldamaget0farmland,wildlife,andwatertreatmentsystemsandpowergenefat0rs.ThepurposeofthispaPeristoprovidean0verallperspectiveonthemagnitudeandtrendsofsedimelltasap0llutritintheUnitedStates.2CURRENTKNOWLEDG… 相似文献
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对化探在发现砂宝斯岩金矿床过程中所采用的技术方法进行了总结,即选区→1:5万水系沉积物测量→1:5万土壤测量→1:1万土壤测量→工程验证发现矿体。提出了在取得同样找矿效果的前提下,对工作程序和技术方法的改进意见,即选区→1:10万水系沉积物测量→1:5万土壤测量→1:2万-1:1万土壤测量→1:1万土壤测量→工程验证,从而用较少的投资更快地发现矿体。 相似文献
247.
独居石电子探针定年及其在新疆东天山变质作用研究中的应用 总被引:11,自引:1,他引:10
以化学法独居石电子探针定年的原理以及前人改良过的年龄计算公式为基础,利用全微分和最大误差原理,确定了年龄误差计算新方法。并用Visual C语言在Windows平台下编制出了计算年龄和年龄误差的计算机程序。运用此程序对前人公开发表的分析资料和计算的年龄以及年龄误差数据进行了重新计算,验证了给出的误差公式的可靠性。同时,利用JXA—8100电子探针仪对新疆东天山变质沉积岩的两个样品(KM2127—5,DK2107—2)中的独居石进行了电子探针微区U—Th—Pb成分分析。结果表明,样品DK2107—2记录了两期变质作用,峰期年龄分别是341.0±3.9Ma和255.2±3.3Ma,其中最主要的变质峰期年龄为341.0±3.9Ma,该期的矿物组合为Ky+St+Bt+Pl+Q+/-Or;而255.2±3.3Ma和样品KM2127-5记录的变质峰期年龄262.3±4.4Ma为次要变质峰期年龄,该期矿物组合是Cord+Bt+Pl+Or+Q。分析结果与前人用^40Ar—^39Ar法得到的结果相吻合,表明独居石电子探针定年技术是一种可靠有效的测年方法。 相似文献
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249.
中国生态脆弱带人地关系行为机制模型及应用 总被引:22,自引:2,他引:20
以农牧交错带为研究对象,通过建立人地关系行为机制模型,探讨外部社会经济因素影响土地退化的机制,并重点就当前正在实施的退耕还林还草政策所带来的生态经济效果进行分析。模型拟合结果显示,利用玉米及农作物秸秆作为饲料,扩大舍饲动物饲养,或者扩大种植葵花或油料作物等商品作物以替代自给性作物糜子,将可以在不加剧水土流失的前提下增加农户收入。模型结果还显示,非农就业机会增加时,农户会减少坡地垦殖。这表明推进农村工业化和城镇化发展,增加农民非农就业机会,鼓励农民进城的政策对于黄土高原的水土保持也是有促进作用的。 相似文献
250.
Hikaru Komatsu Tomonori Kume Yoshinori Shinohara Yoshiyuki Miyazawa Kyoichi Otsuki 《水文研究》2010,24(17):2440-2451
Japan developed large areas of coniferous plantations for timber production between the 1950s and 1970s; however, forestry practices such as thinning, pruning, and harvesting in most of the plantations have declined since the 1980s. Researchers speculated that reduced forestry practices could reduce run‐off and therefore available water resources. As a countermeasure to this potential risk, many local governments have introduced local taxes to stimulate forestry practices in the plantations. However, no studies have presented evidence for decreased annual run‐off and/or low flow in watersheds where forestry practices have declined. As a starting point for assessing this risk, this study examined potential changes in the annual run‐off and low flow in the Terauchi watershed. A large area of this watershed was covered with coniferous plantations. We first surveyed the annual investment in forestry operations and the number of forest owners in the city of Amagi. (Note that Amagi includes the Terauchi watershed.) Both decreased during the period 1979–2007, indicating reduced forestry practices. The frequency distribution of plantation tree ages in the watershed also suggested reduced forestry practices. After excluding the effect of precipitation, we examined potential changes in the annual run‐off and low flow during the period 1979–2007. We did not observe significant decreases in the annual run‐off and low flow during the period. Thus, the risk of decreased water resources might be less than expected, and countermeasures to the risk should be reconsidered. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献