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991.
Kenya is under the influence of the seasonal reversal of the Indian ocean monsoons. However, its coastal belt, up to about 50 km inland, exhibits original climatic features. Hierarchical clustering of mean monthly rainfall for a large number of stations, particularly in the south-eastern region, strongly differentiate a maritime climate characterised by enhanced and delayed "long rains" and no dry season in the northern summer. Most of these rains fall at night or in the morning. Using daily rainfall data and twice-daily surface and upper-air wind observations, monsoon-breeze interactions and their role on April–August coastal precipitation are assessed. Rain spells common to the whole Kenya coast are associated to a slight weakening of the sea breeze, a strong easterly or south-easterly wind anomaly over most of Kenya at around 850–700 hPa, and sea surface temperatures greater than air temperatures.  相似文献   
992.
Changes in annual frost frequency and annual frost accumulation associated with a variety of temperature change scenarios are mapped for northern England. Estimates of future changes are obtained through application of analytical theory to convert predictions of mean daily minimum temperatures and their inter-diurnal variability to accumulated frost degrees and frost frequency. The baseline climate is provided by regression analysis of surface data involving up to ten terrain variables. Future scenarios include warm and cold analogues, maritime and continental airflow scenarios, arbitrary warming and two general circulation model (GCM) simulations: UKHI (United Kingdom Meteorological Office High Resolution GCM Equilibrium Experiment) and GISS (Goddard Institute for Space Studies). Considerable contrasts emerge between scenarios, with substantial reductions in frost frequency and accumulation in the two GCM 2 *CO2 simulations. This is to be expected in a maritime area where small changes in temperature have a large influence on parameters involving threshold temperatures. Increases in frost occur under the continental airflow scenario. Changes in frost do not necessarily complement those in accumulated warmth, and therefore indices combining possible changes in warmth and frost are helpful.  相似文献   
993.
Nutrition in cod (Gadus morhua) larvae and juveniles   总被引:1,自引:0,他引:1  
  相似文献   
994.
南日岛海域溶解态Cu、Pb、Cd含量及其与营养盐的关系   总被引:3,自引:0,他引:3  
高淑英  邹栋梁 《台湾海峡》1995,14(2):195-198
本文首次报道了福建南日岛海域溶解态Cu、PB、Cd的含量,探讨了它们与营养盐的关系。1990年5月溶解态Cu、Pb、Cd的平均含量分别为0.84、0.230、0.023μg/dm3;1990年10月分别为0. 78、0.290、0. 033μg/dm3。其5月溶解态Cu与无机氮N(NO3-+NO2-+NH4 )线性回归的相关式为Cu(μg/dm3)=-0. 789+0.328N(μmol/dm3),相关系数r=0.853,原子比△Cu:△N=5.17×10-3:1。  相似文献   
995.
大鹏湾夜光藻赤潮的营养动力学模型   总被引:1,自引:0,他引:1  
根据大鹏湾夜光藻Noctilucascintillans赤潮发生要素的结构关系,利用生物种群生态学和营养动力学的原理,提出夜光藻-硅藻-营养物质三者相关的动力学模型,模型中的参数将体现海况环境的有关因素。文中利用微分方程动力系统理论对模型作出定性分析,给出赤潮发生与否的某些判别条件;并根据1991年3月1日一4月30日大鹏湾所发生的夜光藻赤潮数据分别对1次赤潮全过程和有连续3次赤潮的情形进行了有效的数值模拟,所得结果对赤潮的预测预报研究有一定的参考价值。  相似文献   
996.
对南海6种不同种类或不同生长海域的马尾藻进行营养成分分析,然后与海带和紫菜比较,进行营养学评价。结果表明,马尾藻含有丰富的膳食纤维、褐藻淀粉、矿物质和维生素以及优质的高度不饱和脂肪酸和合理的必需氨基酸组成,其中必需氨基酸的化学评分为80~88之间,远高于海带和紫菜,其余成分与海带、紫菜接近,可作为保健食品和药物的优质原料  相似文献   
997.
In order to determine the relative aging slams of upwelled or vertically mixed water in the northern Taiwan Strait, a recently developed method of calculating the degree of nutrient consumption (DNC) was employed. Upwelling was detected at a water depth of about 75m in summer. Bottom waters in the aphotic zone and newly-upwelled waters in the euphotic zone were found to be low in terms of their DNC. In general, a low DNC was noted alongside the other traditional upwelling indicators, such as lower temperature and degree of oxygen saturation, but higher salinity, apparent oxygen utilization, nutrient contents and chlorophytt-a. Enhanced vertical mixing, but without an apparent upwelling signal, was detected near the same location in winter.  相似文献   
998.
The ratios of phosphorus and nitrogen originating from land and the open ocean in the Seto Inland Sea, which is the largest semi-enclosed coastal sea in Japan, have been estimated from data on total phosphorus and nitrogen loads and observed concentrations of total phosphorus and nitrogen. The ratios of land-origin and open-ocean-origin total phosphorus and nitrogen in the Seto Inland Sea are 0.28:0.72 and 0.19:0.81, respectively.  相似文献   
999.
Nutrient Fluxes through the Taiwan Strait in Spring and Summer 1999   总被引:9,自引:0,他引:9  
Transports of water and nutrients (N and P) through the Taiwan Strait were calculated using chemical hydrography and currents observed in May and August 1999. The surveys were conducted along a transect across the strait in the middle section. The velocity fields were determined by phase-averaging currents measured using shipboard Acoustic Doppler Current Profiler (ADCP) on two repeats, which were separated by 1.5 cycles of the dominant M2 tide. Nutrient distributions were also derived from phase-averaged data. The volume transports determined from the two surveys were similar (2.0 Sv and 2.2 Sv, respectively). By contrast, the nutrient fluxes obtained in August (1.82 kmol N/s and 0.34 kmol P/s) were significantly higher than those in May (0.96 kmol N/s and 0.16 kmol P/s), apparently due to coastal upwelling under southwest monsoon in summer. The rather low N/P ratios (6.0 and 5.4 by atoms) of the nutrient fluxes were attributed to the widespread N-deficiency in the upper water column of the North Pacific. The nutrient fluxes were fed mainly through a meridional deep channel off southwest Taiwan. The nutrient contributions from the Taiwan Strait to the East China Sea in spring and summer are comparable to the total riverine contributions from the Changjiang (also know as the Yangtze River) and other smaller rivers for nitrogen, but 8–17 times larger than the latter for phosphate. Therefore, the Taiwan Strait inflow may serve as an important supplement for the P-limiting condition in the huge coastal plume in the East China Sea.  相似文献   
1000.
防城湾水质特征及营养状况趋势研究   总被引:7,自引:0,他引:7  
根据1983—1984年度、1990年度及1996——1997年度3个不同时期的调查研究资料,分析研究了防城湾的水质特征及其营养状况。结果表明:该湾水体中的盐度、pH呈明显下降趋势,而有机污染物含量则呈上升趋势,其余因子无明显规律性变化;但相关分析显示,陆源输入对各化学因子具有主导控制作用,生物同化作用次之。N、P、Si营养盐中,N为1983—1984年度初级生产力的限制因子:1990年度演化为P和Si;1996—1997年度N、P、Si均呈充足状态,尤以Si最为显著。通过污染指数A及营养状态指数E的统计分析,该湾水质具有向污染型及富营养型演化的明显趋势。  相似文献   
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