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31.
1957~2004年盘锦芦苇湿地的气候变化特征分析   总被引:4,自引:0,他引:4       下载免费PDF全文
利用1957~2004年盘锦湿地常规气象资料,分析了盘锦湿地的日照、温度、降水和风速的变化特征。结果表明:日照时数的月变化呈双峰曲线,5月和9月表现为日照高峰,7月为日照低谷;近48 a盘锦湿地的年平均气温呈显著的上升趋势,冬季增温最明显,其次为春季,夏季增温最弱,年平均极端最低温度呈显著的上升趋势;近48 a的年平均风速呈显著的下降趋势,月平均风速变化趋势呈双峰曲线。  相似文献   
32.
吉林向海沼泽湿地土壤氮素的剖面分布   总被引:5,自引:1,他引:5  
本文以二百方子湿地和付老文泡湿地为研究对象,对比分析了两典型区湿地土壤不同形态氮素和全氮含量在生长期和成熟期的剖面分布特征及其差异,结果表明封闭性湿地和开放性湿地土壤剖面的物理性状存在地域差异;封闭性湿地在两物候期内土壤氮素含量的剖面分布特征相似,均表现为由表层向下减少的总体分布趋势;开放性湿地土壤中碱解氮、有机氮和全氮含量剖面分布特征与封闭性湿地一致;但铵态氮含量的剖面变化则表现为先增后减的变化趋势,且硝态氮在成熟期内出现累积峰.  相似文献   
33.
Wetlands are vulnerable to groundwater extraction, which has proven detrimental to aquatic ecosystems around the planet. As wetlands rank among the world’s most endangered ecosystems, versatile strategies are required to protect them. This paper provides a modelling-based method to delineate protection buffers in wetlands subject to groundwater extraction. The technique is sufficiently flexible to cater to a wide variety of conditions, and simple enough to underpin management decisions on a daily basis. A numerical model is used to obtain a map of the critical rate of groundwater abstraction, based on the distance between wetlands and suitable discharge thresholds. The outcomes determine the allowed pumping rate at any point under steady and transient-state conditions. A new iteration is developed every time a new pumping allowance is made. This procedure is demonstrated by means of hypothetical scenarios, as well as by a case study application in the Valle del Cauca region, Colombia.  相似文献   
34.
The present study focusses on the analysis of water stable isotopes to contribute to understanding the hydrology of the Lake Urema wetland system in central Mozambique towards conservation management.Lake Urema Wetland is located in the Gorongosa National Park at the southernmost extent of the East African Rift System and is situated entirely within the Urema catchment. Of particular concern to the park’s management is the understanding of hydrological processes as these may trigger transformations of ecosystems, habitat losses and wildlife migrations. Concerns over the Lake Urema wetland’s drying up and the trapping of sediments in the floodplain have been raised for some time by conservationists.Water samples were collected for stable water isotope analyses during the wet and the dry seasons for the period 2006–2010 from springs, boreholes, rivers, and Lake Urema. In addition monthly composite precipitation was collected at two rain gauges.The results show that Lake Urema is maintained throughout the dry season merely from water generated during the wet season. It receives water from wet season precipitation and the runoff generated from this precipitation. The water source areas of the lake are the Gorongosa Mountain and the Barue Basement geomorphological units. Consequently, the source of the sediments which have been trapped into the lake and the floodplain has to be identified in these two catchment areas and urgent action is required to rescue the lake. This water body constitutes a groundwater buffer system which supports a unique wetland landscape. The annual inundations’ processes leading to the recharge-drainage cycle in the floodplain are most sensitive to the deposition of sediments, changing hydraulic gradients, and reducing wet season inflows and increasing drainage rates.  相似文献   
35.
绍兴镜湖生态旅游开发与保护   总被引:1,自引:0,他引:1  
周国忠 《湖泊科学》2007,19(5):622-626
以绍兴镜湖国家城市湿地公园为案例,简要分析了镜湖开发与保护中存在的城市发展、原住居民生产生活、生态系统保护与游客利益四者之间的博弈关系,重点对其生态旅游开发与保护模式进行了总结,认为绍兴镜湖生态旅游开发与保护是"B"模式 "国家公园"模式的融合.文章还总结了镜湖生态旅游开发主要从分级保护、旅游项目开发生态性、湿地生境恢复、旅游交通组织、客流量控制及生态农业模式等方面协调开发与保护的关系.提出了今后城市湿地旅游开发与保护的研究方向.  相似文献   
36.
微曝气垂直流湿地处理城郊低浓度生活污水模拟实验   总被引:1,自引:0,他引:1  
本文提出微曝气垂直流湿地的概念,并通过柱状模型实验模拟研究了其对云南滇池流域城郊低浓度生活污水的处理效果.测定了模型的氧利用效率,最高为14.04%.在高水力负荷15.29m3/(m2·d)、气水比1:2的条件下,BOD5和NI4-N去除率分别为74.4%和63.5%,出水平均含量分别为4.96mg/L和272mg/L.结果说明,微曝气垂直流湿地工艺能满足低浓度生活污水高水力负荷的处理要求,微曝气耗能折价O.04-0.05元/m3.  相似文献   
37.
Abstract

This study examined the end-of-winter snow storage, its distribution and the spatial and temporal melt patterns of a large, low gradient wetland at Polar Bear Pass, Bathurst Island, Nunavut, Canada. The project utilized a combination of field observations and a physically-based snowmelt model. Topography and wind were the major controls on snow distribution in the region, and snow was routinely scoured from the hilltop regions and deposited into hillslopes and valleys. Timing and duration of snowmelt at Polar Bear Pass were similar in 2008 and 2009. The snowmelt was initiated by an increase in air temperature and net radiation receipt. Inter-annual variability in spatial snowmelt patterns was evident at Polar Bear Pass and was attributed to a non-uniform snow cover distribution and local microclimate conditions. In situ field studies and modelling remain important in High Arctic regions for assessing wetland water budgets and runoff, in addition to model parameterization and validation of satellite imagery.

Editor Z.W. Kundzewicz

Citation Assini, J. and Young, K.L., 2012. Snow cover and snowmelt of an extensive High Arctic wetland: spatial and temporal seasonal patterns. Hydrological Sciences Journal, 57 (4), 738–755.  相似文献   
38.
Applications of hydrological models to northern wetland-dominated regions have been limited in the past to a few case studies on small basins employing ‘lumped’ models. Only recently have there been attempts to apply the grouped response unit (GRU) distributed modelling approach using terrain classifications to these same basins. This study summarizes recent efforts in applying such a model. For the purposes of implementing the GRU approach, terrain types that are hydrologically significant and characteristic to the wetland-dominated regime were successfully discriminated using a principal component analysis and a hybrid unsupervised/supervised classification technique on Landsat–Thematic Mapper imagery. The terrain classifications were then used as input into a distributed hydrological model for calibration and validation using recorded spring runoff events. Preliminary model applications and results are described. Calibration to a historic spring runoff event yielded an r2 value of 0.86. Model validation, however, yielded much poorer results. The problems of model applicability to this region and limitations of sparse data networks are highlighted. The need for more field research in this type of hydrological regime, and associated improvements to the model parameter set are also identified.  相似文献   
39.
利用4个连续进水的垂直流人工湿地,比较分析水位对污染物去除效果的影响,研究湿地中植物对氮磷去除的贡献,阐析湿地中脱氮功能菌数量的演变规律。3个湿地栽种黄花鸢尾,水位分别控制在19、51和84cm,另一个湿地不栽种植物,水位为51cm。结果表明,水位对氮和有机物的去除有显著影响(p<0.05),栽种植物的湿地中,51cm水位时总氮去除率(67.4%~79.2%)最高,19cm水位时氨氮(85.3%~93.0%)和COD(81.8%~92.9%)去除效果最好。试验中黄花鸢尾均生长良好,植物吸收对总氮(Total nitrogen,简称TN)和总磷(Total phosphorus,简称TP)去除的贡献分别为19.2%~27.3%和14.7%~19.2%;植物地上部分发挥更重要作用,其TN和TP含量及对TN和TP的吸收量均高于地下部分。湿地表层基质中3种脱氮功能菌数量均随运行时间的增加而显著提高,亚硝化细菌和硝化细菌数量分别为10~4~10~6和10~5~10~7 MPN/g,随水位升高而减少;反硝化细菌数量为10~3~10~6 MPN/g,随水位升高而增加。  相似文献   
40.
滨海湿地作为一种具有多种功能和蕴含丰富资源的生态系统,是人类重要的生存环境之一。湿地土壤重金属污染问题是当前湿地科学领域内的热点话题。为研究河北省滦南滨海湿地重金属污染特征,本文利用单因子指数法、内梅罗综合污染指数法和地累积指数法对重金属污染状况进行评价。结果表明:铜(Cu)、锌(Zn)、铬(Cr)、铅(Pb)、镉(Cd) 的单因子质量指数均小于1.0,说明研究区重金属含量小于土壤背景值,土壤未受到污染。内梅罗综合指数法Cu、Zn、Cr、Pb、Cd 指数均小于0.7,表明滦南湿地土壤重金属污染水平处于未污染。湿地各区域重金属地累积指数为无污染或较轻污染,其中Pb 污染为较轻污染,监测点主要与人类活动有关。利用地累积指数分析认为Pb 在湿地北区为轻度污染水平,经调查发现该区域主要为居民点,人类活动频繁,其他重金属均无污染。河北滦南滨河湿地土壤未受到重金属污染,湿地土壤环境较好。  相似文献   
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