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261.
The quest for sustainable communities might be fostered by a new ‘place-based’ governing approach that engages civil society and other actors in local decision-making processes. In Canada, lessons can be learned from the establishment and maintenance of biosphere reserves by networks of local communities of interests and other organisations. Biosphere reserves are created to promote conservation, biodiversity and sustainable livelihoods. Municipal and public participation in these reserves can be encouraged, promoting a local sense of place as well as sustainable community and regional development. An examination of two Canadian biosphere reserves, Riding Mountain and Long Point, illustrates how local governments and these reserves might assist each other in their mutual goals of long-term sustainability while offering a worthwhile model of local collaborative, place-based governance.  相似文献   
262.
贵州岩下自然保护区的野生大鲵资源现状及历史动态   总被引:1,自引:0,他引:1  
为了解野生大鲵在喀斯特区域的分布规律与种群历史动态,于2006年6月份、2007年8、10月份对长江支系沅江水域的贵州省贵定县岩下省级自然保护区野生大鲵(〖WTBX〗Andrias davidianus〖WTBZ〗)种群资源状况与捕获量进行了调查,并对繁殖洞穴涌苗现象进行了分析。初步查明岩下野生大鲵种群集中分布在一个以地下水域为依托,地面水网与地下河流相连的集中区域,栖息地由地下(洞穴)与地面水域广布缩小到以地下水域为主;根据繁殖洞穴的鲵苗涌出量与大鲵繁殖特征,推算岩下野生大鲵种群密度约为0085 kg/m2,总资源量约为1 700 kg;捕获量表明,种群数量在20世纪80年代末后急剧减少,90年代中期至2000年后,数量变化趋于缓和。岩下保护区野生大鲵分布的集中性、生境自然条件的优越性以及繁殖洞穴的大规模涌苗现象在全国均属少见。由于受到外在致危因素影响,大鲵的生境遭到破坏、种群生存受胁,亟待加强资源的保护与管理。  相似文献   
263.
吉林向海自然保护区湿地资源的保护   总被引:4,自引:0,他引:4  
在分析吉林向海自然保护区湿地资源现状及其保护意义的基础上 ,针对湿地资源受到的严重威胁 ,提出了保护对策。  相似文献   
264.
江西省山地风场风能资源储量及特征分析   总被引:1,自引:0,他引:1  
论文利用数值模拟GIS空间分析法以及实测与野外勘察调研两种方法规划了江西省山地风能资源的具体分布并定量估算了其储量,此外,还利用山地2座测风塔资料,详细地分析了山地风能资源特性,结果表明:江西省高山地区风能资源呈沿山脉走向的线状分布或孤立山峰的点状分布,技术可开发量约为111×104 kW,技术可开发面积约为136 km2,装机容量约为148×104 kW。山地低层风速和风功率密度较大,随高度的增加略有增大,风切变指数很小,分别为0.017、0.098。山地风场风速和风功率密度日变化明显呈U型分布,正午前后风速最小,凌晨至清晨风速较大,最大风速与最小风速相差1~2 m/s;山地风场有两个接近相反的主导风向,集中在NW-N以及SSW-SSE扇区,对于风机机组布局较为有利。  相似文献   
265.
基于CA-Markov模型的向海湿地土地覆被变化动态模拟研究   总被引:10,自引:0,他引:10  
论文借助地理信息技术,采用CA-Markov模型,以1988、1996、2003年3个相同时相的TM遥感影像作为数据基础,并结合地形图和相应的交通、气候等数据对向海自然保护区未来的土地覆被类型进行动态模拟和预测。在模型建立过程中,通过马尔可夫模型求出转移概率矩阵,确定CA模型转换规则。利用CA-Markov模型对向海自然保护区未来的土地覆被类型转化方向进行了动态模拟,将模拟结果与已有的土地覆被类型对比,得出模拟精度达到74.46%。据此对向海自然保护区2010、2018年土地覆被类型做出预测。预测结果表明:向海自然保护区土地覆被类型整体趋势不容乐观,湿地面积在大量减少,林地和草地呈减少趋势,耕地、居民地、未利用地呈增加趋势,其中未利用地面积增加最多。该方法可以对向海自然保护区的湿地保护和动态监测以及可持续发展提供依据。  相似文献   
266.
分别在 2 0 0 1年和 2 0 0 2年用国家标准《水质 -微型生物群落监测 -PFU法》在香港米浦自然保护区的基围塘和红树林中监测水质 .在 3个基围塘中共鉴定出 91种原生动物 ,为香港地区的首次记录 .同时在群落级水平上分析了4种生态结构参数和 5种功能参数 .用化学的方法成功地监测出在此 3个基围塘的PFU挤出液中 pp′-DDE和PCB的浓度 ,并且获得两年一致性的结果 .本文化学和生物学结合的研究结果为测定水中超痕量持久性有机污染物 (POPs)的环境暴露与生态毒性提供了一种新的尝试 .图 3表 8参 2 7  相似文献   
267.
焦健 《环境与发展》2020,(2):193-194
随着我国经济的高速发展,经济活动也开始向自然保护区延伸,这就必然导致各种破坏自然保护区的现象不断出现。因此,加强自然保护区依法严格的科学管护,刻不容缓。  相似文献   
268.
In 1990, grazing was introduced in a section of Meijendel, a coastal sand dune system near The Hague, The Netherlands. After five years an evaluation was made of the effects of grazing on vegetation development. Three transects were established, two in grazed areas and one in an ungrazed area. Field survey data were classified by means of TWIN-SPAN, ordinated with Detrended Correspondence Analysis and the resulting vegetation types interpreted according to Westhoff & den Held (1969). All associations were found in both the grazed and the ungrazed areas, but at the subassociation and variant level some communities appeared to be restricted to the grazed area. These variants were five grassland variants characterized by disturbance indicators such asSenecio sylvaticus andCynoglossum officinale. The total number of plant species in the 19 permanent plots, which had been observed to have been decreasing since 1960, showed a considerable increase after the introduction of horses and cows in 1990. A marked decrease in the cover ofCalamagrostis epigejos andCarex arenaria since 1990 was evident, while in some plots species such asRibes rubrum andViburnum opulus increased considerably. A series of false-colour aerial photographs were used to compare vegetation structure in the three transects between 1990 and 1995. In the grazed area the tall grass vegetation had almost totally disappeared, whereas the areas of open sand. sand with moss and lichens, and low grass vegetation had increased and the pattern had become more fine-grained. In the ungrazed area the area covered by low grass vegetation had increased at the expense of the area of sand with moss and lichens and the pattern had become more coarse-grained.  相似文献   
269.
Background, aim, and scope  Foraging patches can be described as a nested hierarchy of aggregated resources, implying that study of foraging by wild animals should be directed across different spatial scales. However, almost all previous research on habitat selection by the giant panda has concentrated upon one scale. In this research, we carried out a field study to understand foraging patch selection by giant pandas in winter at both microhabitat and feeding site scales and, for the first time, attempted to understand how long it would stay at the feeding sites before moving on. Materials and methods  The field survey was conducted from November 2002 to March 2003 at Fengtongzhai Nature Reserve (102°48′–103°00′ E, 30°19′–30°47′ N), Baoxing County of Sichuan Province, China, to collect data in both microhabitat and control plots. The microhabitat plots were located by fresh feces or foraging traces left by giant pandas, and the control plots were established to reflect the environment. Within each microhabitat plot, one 1 × 1 m2 plot was centralized at the center of each feeding site, in which numbers of old bamboos and old shoots, including eaten and uneaten, were counted, respectively. Results  The results showed that winter microhabitats selected by this species were characteristic of gentle slopes and high old-shoot proportions and that the latter was even higher at feeding sites. Two selection processes, namely, from the environment to microhabitats and from the latter to feeding sites, were found during this species’ foraging patch utilization. Giant pandas preferred to eat old shoots to old bamboo at feeding sites in winter and did not leave unless old-shoot density fell to lower than the average in the environment. Discussion  Both microhabitats and feeding sites selected by giant pandas were characteristic of high old-shoot density, indicating that the preferred food item had a significant influence upon its foraging patch selection. The preference for gentle slopes by giant pandas was presumed to save energy in movement or reflect the need to sit and free its fore-limbs to grasp bamboo culms when feeding but also seemed to be correlated with an easier access to old shoots. The utilization of old shoots at feeding sites was assumed to help maximize energy or nutrient intake during their foraging. Conclusions  The difference between microhabitat plots and control plots and between microhabitats and feeding sites uncovered a continuous selection process from the environment via microhabitats to feeding sites. The utilization of old shoots at feeding sites was parallel to the marginal value theorem. The selection and abandonment of foraging patches by giant pandas was an optimal behavioral strategy adapted to their peculiar food with high cellulose and low protein. Recommendations and perspectives  Our results uncovered the importance of multiple scales in habitat selection research. To further understand the process of habitat selection, future research should pay more attention to resolve the question of how to locate foraging patches under dense bamboo forests by the giant panda, which was traditionally considered to have poor eyesight, although our research has answered what type of habitats the giant panda prefers and when to leave.  相似文献   
270.
为了弄清南岳自然保护区内藤本植物资源现状,对该区内藤本植物进行了多样性调查研究。结果表明:野生藤本植物共计59科129属282种(含变种),其中蕨类植物有3科5属6种,双子叶植物有50科112属250种,单子叶植物有6科12属26种,裸子植物缺乏。该区地理成分复杂多样,科级地理成分有8个分布型,属级地理成分有12个分布型,种级地理成分有11个分布型,均以热带成分为主,温带成分占有较大比例,说明该区热带成分向温带渗透和过度的性质。藤本植物的生活型,以木质藤本占优势,为6064%,草质藤本占39.36%,一年生藤本占1441%。藤本植物的攀援类型分为4型9亚型,以缠绕类为主,占37〖JP2〗94%;其次为吸固类,占2305%,又可分为不定根类、吸盘类和寄生类3亚型;卷曲类占2093%,又可分为须卷类、柄卷类和枝卷类3亚型;刺蔓类最少占1809%,又可分为枝蔓类和钩刺类2亚型。该区藤本植物资源丰富,在垂直绿化与经济开发上具有十分广阔的前景  相似文献   
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