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171.
The main objective of this paper is to examine pollution threat, especially to the groundwater resources, around Tarapur industrial area (also called the Tarapur MIDC area) located on the Arabian Sea Coast in Thane District of Maharashtra State, India and suggest remedial measures that may also be relevant to other industrial areas on the Indian Sea Coast. One hundred and thirty one samples were collected from various sources, such as dugwells, borewells, dug-cum-borewells, effluent sumps, drainage channels (effluent channels), creeks and ocean, for chemical analyses. These analyses show that the area in general is characterized by hard water and high salinity hazard, possibly due to its proximity and hydraulic connection with the sea. Although the potability of groundwater is questionable in certain pockets, it is good enough for irrigation purposes at present. Low pH value and high heavy metal contents in the adjoining Muramba creek water is a matter of great concern and may be attributed to the indiscriminate disposal of industrial effluents to the drainage channels connecting the creek. Muramba Creek is well connected with the Arabian Sea, and there are evidences of seawater intrusion around this creek. Because of the fact that Muramba Creek is highly polluted, and is hydraulically connected with the dugwells and borewells surrounding the creek, it cannot be ruled out that the groundwater around this creek is susceptible to contamination. Unless measures are not taken immediately to stop the indiscriminate disposal of the solid wastes and liquid effluents in open ground and drainage channels, and measures are not taken to maintain the appropriate pH values at the effluent treatment facilities before their disposal, the problem would indeed be formidable one day, and it will be too late then for the authorities to take care of the resulting maladies. Few suggestions have been given for controlling and managing the industrial pollution around the Tarapur MIDC area. These suggestions are relevant to other industrial areas situated on the 7,000 km long Indian Sea Coast.  相似文献   
172.
The surface colour and temperature fields of the Mediterranean Sea, as appearing in time series, of basin-wide images available in the CZCS (1979–1985) and AVHRR (1982–1991) historical archives, differentiate between basin interior and continental margins affected by coastal patterns, river plumes, and mesoscale features. The original data were processed to apply calibration factors, to correct for atmospheric contamination, and to estimate chlorophyll-like pigment concentration and surface temperature. Composites were derived, as monthly and annual means, using a fixed equal-area projection with a 1-km2 pixel grid. Enhanced pigment values and lower temperatures along the northern coastal areas (i.e. the Ligurian, Provençal and Balearic basins, as well as the Adriatic, and Aegean Seas) have been associated with the impact of runoff from continental margins (i.e. both a direct impact due to the sediment load and one induced on the planktonic flora by the associated nutrient load) and with vertical mixing due to the prevailing winds (i.e. the Mistral in the northwest, the Bora in the Adriatic, the Etesians in the Aegean). The pattern of increasing pigments and decreasing temperatures in seen to develop in the monthly images from the coastal zone towards the open sea from summer to winter, and then back from winter to summer. The southern coastal areas show different values, namely lower pigments and higher temperatures (except in areas where the data are altered by signal contamination). It is suggested that differences in geomorphology and meteorology of the basin margins have an impact on both water biogeochemistry and dynamics, influencing the biooptical and thermal properties of the various sub-basins, and of the entire Mediterranean region.  相似文献   
173.
Trace elements (22) and stable isotope ratios (δ15N and δ13C) were analyzed in marine organisms from shallow (SW) and deep-water (DW) of the East China Sea to understand biomagnification and prey source of trace elements. In the benthic marine organisms from DW, δ15N values were negatively correlated with Ba, Cu, Ag, Mo, Sr, As, and Co concentrations. This may be due to the specific accumulation in lower trophic animals and/or the biodilution through the food web in DW. Relationships between δ15N and concentrations of Co, Cr, Bi, and Tl in fish and Ag, Bi, V, Hg, and Tl in crustaceans showed positive correlations, suggesting that trophic position was affecting the concentrations of those elements in phyla, with higher trophic animals retaining higher concentrations than the lower trophic animals. Positive correlations between δ13C and Rb were observed in marine organisms. Therefore, Rb may be a possible substitute of δ13C as tracer of prey source in the East China Sea although further investigation is required.  相似文献   
174.
采用高通量测序-分子鉴定分级技术于2019年对黄海北部海域真核微藻粒级结构进行了研究.结果发现,春季以中、小粒级为主,夏季以小、大粒级为主,秋季以大粒级为主,春、夏、秋季小、中、大粒级微藻比例为39:51:11、40:24:36、26:13:62.小粒级微藻优势种为细小微胞藻和金牛微球藻,中粒级微藻优势种为剧毒卡尔藻,...  相似文献   
175.
目的 明确南海高温高压含CO2气井管柱材料腐蚀适用性,指导现场管柱材料选择.方法 采用高温高压釜腐蚀实验仪器对井筒高温高压环境条件下不同材料腐蚀速率进行实验分析,并采用扫描电镜及能谱分析仪对腐蚀实验后试样腐蚀形貌进行分析,评价不同井筒环境下管柱材料腐蚀适用性.结果 150℃条件下,材料腐蚀速率随分压的增加而增大,同时随...  相似文献   
176.
东海区带鱼伏季休渔效果及其资源的合理利用   总被引:5,自引:0,他引:5  
根据2002-2003年东海区带鱼年龄鉴定资料,并引用以往的带鱼渔业生物学研究结果,作为估算带鱼死亡系数和建立动态综合模型所需的有关参数值估算的依据,从而运用Ricker动态综合模型分析了在现行渔业条件下东海区带鱼伏季休渔效果和带鱼资源利用状况以及变更渔业利用情况对带鱼渔业所产生的影响。结果表明:在现行渔业下(tc=0.5a,F=2.61/a),东海区实施3个月的伏季休渔制度能使年平均资源量增加87%,年产量增加29%,渔获平均体重增加42%;带鱼资源的利用虽处于捕捞过度状态之中,但尚能承受较大的捕捞压力,资源结构利用不合理之处是捕捞大量的幼鱼群体,渔获个体依然过小,渔获平均体重仅为75g/ind.;单位补充量渔获量(Y/R)随tc变化的影响大于随F的变化,建议在维持现有伏季休渔制度下,应逐渐降低捕捞强度,并以提高起捕规格放大网目尺寸作为今后一个时期首选的渔业管理目标,应是较为现实的资源合理利用措施。  相似文献   
177.
春季黄渤海溶解有机碳的平面分布特征   总被引:1,自引:0,他引:1  
依据2010年4~5月对黄渤海调查所得的数据,分析了黄渤海溶解有机碳(dissolved organic carbon,DOC)的含量及其平面分布特征,并对其影响因素进行了初步探讨.结果表明,2010年春季黄渤海DOC的浓度范围为0.96~4.71 mg.L-1,平均浓度为2.27 mg.L-1.平面分布上,DOC整体呈现南北近岸浓度高、中部外海浓度低的特点.在渤海西部近岸、山东半岛东部及长江口东北部均存在高值,尤其是渤海西部近岸,DOC浓度最高达到4.71 mg.L-1,这主要是受河流输入和沿岸流的影响;低值区则主要集中在南黄海中部外海,DOC浓度普遍低于1.50 mg.L-1.  相似文献   
178.
渤海莱州湾沉积物-水界面溶解无机氮的扩散通量   总被引:12,自引:4,他引:12  
为了解不同条件下沉积物中有机物对水体无机氮的贡献,采用野外采样和现场培养法,在1997-05和1997-07莱州湾2个航次进行了沉积物-水界面营养盐扩散通量的实验研究,NO-3和NH+4的扩散通量分别为0.038—3.65mmol/(m2·d)和0.96—2.52mmol/(m2·d).培养结果说明充氮或充空气与加氯化汞或不加氯化汞对沉积物-水界面溶解无机氮的扩散通量没有明显影响.莱州湾底部营养盐的扩散通量与其它地区比较处于中等偏上水平.  相似文献   
179.
南黄海东部海域浮游生态系统要素季节变化的模拟研究   总被引:5,自引:0,他引:5  
利用海洋生态系统动力学垂直一维物理-生物耦合模式模拟研究了南黄海东部海域浮游生态系统要素垂直分布的季节变化.物理亚模型为一维POM模式(Princeton Ocean Model),基于文献结果对垂直混合系数Kh和Km进行了调整;生态亚模型为ERSEM模式(European Regional Sea Ecosystem Model),主要考虑浮游植物、浮游动物、细菌、底栖碎屑和营养盐(氮、磷、硅)等状态变量.模拟结果表明,浮游植物出现一年双峰的态势和夏季次表层叶绿素最大值的现象,春、秋季水华期间,表层叶绿素峰值分别为3.25 mg/m3和0.71 mg/m3.浮游动物和细菌在春季水华后表层出现峰值,分别为143.6 mg C/m3和23.55 mg C/m3.硝酸盐、磷酸盐和硅酸盐的垂直分布均在5-11月呈现表层浓度低、底层浓度高的分布.通过计算碳通量可以看出,在春、夏季,浮游植物对无机碳的摄取量分别为58.944 g C·m-2·quarter-1和68.276 g C·m-2·quarter-1,高于细菌对非生命有机碳的摄取.在冬季,细菌对非生命有机碳的摄取超过浮游植物对无机碳的摄取量.浮游动物在冬季主要摄食细菌,占71%;春、夏季主要摄食浮游植物,可达67.5%.浮游植物对碳的释放主要是以DOC的形式,约占90%.  相似文献   
180.
环渤海海岸大气微塑料污染时空分布特征与表面形貌   总被引:4,自引:0,他引:4  
微塑料污染已成为国内外的热点环境问题.目前,针对大气环境中微塑料污染的研究仅在少数地区开展.为比较环渤海沿海城市大气微塑料污染的长周期分布特征,本研究以烟台、天津和大连3个城市为例,于2018年6月—2019年5月进行大气沉降样品的采集,经体视显微镜、扫描电子显微镜和显微傅里叶红外光谱仪观察,分析了大气微塑料的类型、颜色、粒径、成分、微观形貌及主要成分等特征,并计算了微塑料的大气沉降通量.结果表明,在3个采样点大气沉降样品中共同存在纤维、薄膜、碎片和颗粒4种类型的微塑料,其中绝大部分为纤维类(>90%).大气沉降微塑料的颜色主要包括透明、蓝色、红色、黑色等;粒径大多<1 mm.大气沉降样品中的微塑料主要成分为赛璐玢(>50%)和聚对苯二甲酸乙二醇酯(>30%),且微塑料表面存在明显风化特征.烟台、天津和大连地区单位面积微塑料年沉降量分别为2.7×104、8.9×104和7.2×104粒·m-2.研究结果可为环渤海海岸城市大气微塑料污染与防控研究提供科学依据.  相似文献   
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