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利用第二次全国湿地资源调查的野生动物资源数据,探讨了31个省(直辖市或自治区)湿地中的国家重点保护野生动物分类学特征和数量特征。在31个省(直辖市或自治区)湿地中,共有32科44属60种国家一级保护野生动物,58科123属184种国家二级保护野生动物,其分别占全国国家一级和二级保护野生动物物种数的54.05%和55.76%。31个省(直辖市或自治区)湿地中的国家一级和二级保护野生哺乳类物种数分别与河流湿地面积、湖泊湿地面积显著正相关,鸟类物种数与人工湿地面积显著正相关,因此,为了有效地保护湿地野生动物资源,在加强对河流湿地、湖泊湿地等天然湿地保护的同时,应该关注库塘、输水河等人工湿地的建设。 相似文献
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在美国,孤立湿地与可通航水域没有水文联系,被认为不属于《清洁水法》中的“水域”,联邦无权管辖。为此,陆军工程兵团制定“候鸟规则”,作为对孤立湿地行使管辖权的依据。美国“孤立湿地”保护中的“候鸟规则”对我国的启示在于:(1)应从水文学角度界定孤立湿地,孤立湿地是指与其它水体缺乏联系、相对孤立的湿地,这更符合我国湿地政策的现状;(2)人工“孤立湿地”受保护,除了需满足一定的水文条件,还须是野生动物事实上的栖息地,不应限于建立“栖息地档案”意义下的野生动物栖息地或纳入野生动物重要栖息地名录的栖息地;(3)孤立的人工湿地如果是国家重点保护野生动物栖息地,其管辖权应由中央行使;(4)国家重点保护野生动物栖息地外的其他孤立湿地,面积达到35 hm2以上,也应由中央管辖。 相似文献
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鸭绿江口湿地恢复对迁徙涉禽保护的影响分析 总被引：1，自引：0，他引：1
本文通过对鸭绿江口湿地如何开展人工湿地恢复工作,以及湿地恢复后迁徙涉禽在这一区域的数量、种类以及繁育的变化情况的调查,详细分析了湿地恢复对迁徙涉禽保护的影响,并提出鸭绿江口湿地恢复合理化建议。 相似文献
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江汉平原处于长江中游,地理位置位于东经108°30’～116°10’,北纬29°05’～33°30’之间,计有湿地面积达965334hm^2,素有“水乡泽国”之称。江汉平原是我国主要的湿地农业区域之一,湿地农田水利发达,地下水位高,沟渠纵横。 相似文献
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采用“点轴体系”及“中心地理论”来描述和表征区域人类活动的空间集聚特征,以此反映湿地区域人类活动直接风险来源,通过土壤侵蚀与非点源污染途径,区域非湿地部分(森林、水田、旱地等)通过物质联系(泥沙、氮磷、水等的输出与输入)方式也会对湿地健康造成影响,反映湿地区域人类活动间接风险来源。基于对人类活动影响湿地直接途径和间接途径的区分以及相应部分风险指标的选择,论文最终完成三江平原湿地区域生态风险评价研究工作。结果表明：DMSP/OLS(Defense Meteorological Program Operational Line-Scan System)夜间灯光及多等级道路数据可以用于区域点轴体系描述,从而表征出湿地区域人类活动直接风险来源的空间分布特征,其中高和极高风险源强度等级与区域高等级中心地和高等级道路拟合程度较好;由于较高的生态资产及脆弱性水平,湿地有最高的生态风险水平;三江平原低、中、高和很高风险等级所占比例分别为64.00%、24.28%、10.38%、1.34%,大部分为低和中等风险水平,但有关风险防范任务仍不可掉以轻心,特别是在相应的高等级风险分布区域;南部地区有较高的风险水平,因此需要着重加以保护。从生态系统服务功能来看,一般认为水田、旱地为生产功能区,森林、湿地为生态功能区。过分关注水田、旱地的生产服务功能会造成下游湿地过量的物质输入从而加剧其风险水平;相反,注重森林保育能够减少泥沙、氮磷等大量输出风险,增加流域产流,从而可为下游湿地健康维持作出贡献。因此,水田、旱地与湿地间是一种生态服务权衡关系,森林与湿地间是一种生态服务协同关系,因此,风险管理方面,应强调区域”点轴体系“与湿地间的空间邻接关系,注重湿地重点生态风险来源（地点与方位）的防范以及湿地与非湿地类型间基于生态系统服务功能的权衡及协同管理问题。可为从区域整体水平上削减湿地健康风险水平提供指导和帮助。 相似文献
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湿地保护修复对维护区域生态系统稳定、提升片区洪涝调节、水质净化等功能具有重要意义。以天津大黄堡湿地为例,在“生态+”理念统领下,采用土地适宜性评价、水位多情景分析等方法,统筹考虑湿地修复、保护区人地矛盾、周边区域发展,明确苇田区、苇塘区及过渡区不同分区的主导功能。基于水位差异将湿地核心区域分为保水区、浅水区、富水区,通过湿地肌理重塑、鱼塘整合及修复,营造鱼塘-水塘-复合湿地-芦苇湿地-林地的丰富生境,恢复大黄堡湿地独特生态本底,为人口密集的城镇群区域湿地保护修复提供借鉴。 相似文献
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草海是我国亚热带高原湿地生态系统的典型代表。近年来草海湿地退化加剧,生态环境遭受破坏。草海鸭子塘入湖河口湿地位于草海东部入湖口区域,存在水质恶化、湿地面积骤减等问题。通过开展鸭子塘入湖河口湿地修复工程,选择生态塘作为恢复湿地生境主要措施,并通过科学的工程设计使生态塘融合于自然环境中,达到恢复湿地生态功能及提高生物多样性的目标。 相似文献
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We examine the sequence of changes in the structure of the geosystems of the Primorsky Range (Baikal region) for the last 6000 years, based on a continuous recording of fluctuations of the vegetation reconstructed from spore-pollen complexes of a high peat bog. We determined the chronological timeframe of paleogeographical events. The study showed that there occurred a radical structure transformation of the geosystems in the mid-late Holocene, along with a recurrence of similar landscape transformations caused by the instability of natural conditions. 相似文献
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Eugene V. Artyushkov 《Geophysical Journal International》1984,76(1):173-178
Summary. It is known that flow in the mantle can produce preferred orientation in olivine crystals with seismic anisotropy as a consequence. Flow in the subcrustal lithosphere is unlikely because of the high viscosity. Lenses of high temperature and low-viscosity ( anomalous mantle ) are located under the crust in many tectonically active regions, and viscous flow can easily arise in such material resulting in seismic anisotropy. After cooling, such anomalous mantle acquires high viscosity and becomes incorporated into the lithospheric layer preserving the anisotropy produced by the flows which existed previously. The interaction of the stresses with cracks in the upper crust can be one of the causes of anisotropy in this layer. 相似文献
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我国北方东起黑龙江省嫩江地区, 吉林白城地区及辽宁西部, 包括内蒙兴安盟东南、哲里木、昭乌达、锡林郭勒、乌兰察布、伊克昭等盟的大部地区, 直至河北坝上、陕西榆林北部约26.7万平方公里的幅员范围内, 由于自然条件的特殊性(地表组成物质质地松散、沙粒成分比重很大及气候干旱、多大风, 且年内季风与周期性干旱相吻合), 加上人类不合理开发活动的影响, 成为我国目前沙漠化发展最活跃的地区, 其沙漠化土地近16.5万平方公里, 占全区总面积的61.5%。该地区有较长的经济开发史, 农、牧业相互影响, 交错分布的情况, 在历史上业已形成。据粗略统计, 该区范围内, 有旱作耕地近5, 000万亩, 多以传统的粗放的撂荒种植制进行经营, 长年遭受不同程度的风沙危害, 属于生产水平较为低下的农田类型。这些农田急待整治, 以便提高生产力。由于本区年均降水量在350-450毫米之间, 客观上具有发展旱作农业的可能性。如能合理经营、科学利用其自然资源, 将可能发展成为农、牧业结合的发达地区。从而对我国北方地区农业发展起促进作用。为了深化对沙漠化农田的认识, 揭示其生态失调的实质, 本文将就生态系统观点对其进行分析以寻求有效的整治沙漠化农田的途径。 相似文献
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Summary. Previous geomagnetic measurements in the Rhinegraben have led us to assume that the responsible currents have the properties of direct currents and that they all flow in the sediments filling the graben. In order to verify these conclusions, we have performed measurements in a mine at a depth of 650 m. By comparing the field simultaneously recorded at the surface, in the mine and at the reference station, it is possible to deduce that the anomalous currents have the above mentioned properties. 相似文献
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城市化的开发区模式研究 总被引：14，自引：1，他引：13
我国许多城市通过开发区建设,在短时间内完成了产业和人口的集聚,实现了城市地域空间和人口规模的跳跃性增长和产业结构的转型。由于在这种城市空间增长过程中,开发区建设起了决定作用,因此,这种以开发区带动整个地区城市化的方式可称为"开发区模式"。开发区驱动城市化的机制表现在开发区自身区域的城市化和开发区带动周围农村地区城市化两个层面,并具有快速跳跃性、外驱性和不稳定性、人为性、经济增长模式的单一性和基础设施建设的高标准性等特征。针对开发区建设中出现的问题,提出了促进其健康发展的建议。 相似文献
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L. M. Sorokovikova V. N. Sinyukovich I. V. Tomberg G. I. Popovskaya N. V. Bashenkhaeva N. P. Sez’ko N. A. Zhuchenko 《Geography and Natural Resources》2016,37(3):220-227
Field observations showed that the characteristics of chemical composition of waters and the development of plankton algae in the lakes within the delta of the Selenga river are determined by their flowage. The most open Lake Nekipelovskoe communicates with the Selenga outlets throughout a year, and Lake Zavernyaikha only at the period of an open channel. Lake Semenovskoe and Lake Khlystov Zaton are located in the islands and are isolated from the outlets. According to composition of main ions, the lakes under investigation refer to the hydrocarbonate class, the calcium group. The sum of ions in the water of Lake Nekipelovskoe approaches the one in the Selenga (86?221 mg/dm3), and the highest sums of ions were recorded in the wintertime in the lakes isolated from the outlets (446?743 mg/dm3). The lakes of the delta are characterized by a high trophicity. The maximum concentrations of total phosphorus in Lake Nekipelovskoe and Lake Zavernyaikha were 68 and 122 μg mg/dm3, and in Lake Semenovskoe and Lake Khlystov Zaton ?0.8 and ?0.63 μg mg/dm3, respectively. The most intense development of algae is observed in Lake Zavernyaikha, which is due to the high population of Baikal endemics. Lake Zavernyaikha showed a close negative correlation between the concentration of NO 3 ? , mineral phosphorus and phytoplankton biomass; the correlation coefficient was ?0.8 and ?0.63, respectively. The lakes exhibited increased contents readily hydrolysable organic matter, and a decrease in dissolved oxygen concentration in winter; hydrogen sulfide was repeatedly recorded in Lake Khlystov Zaton. The water quality in the lakes during the springtime varies from “quite clean” to “weakly polluted”; at low-water periods, especially in winters, it can drop to the category of “exceedingly dirty”. The water quality of the Selenga can be influenced by the lakes during spring floods when material accumulated during the wintertime is transported to the river outlets and further to Lake Baikal. 相似文献
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《Geography and Natural Resources》2008,29(2):132-136
The influence of air emissions from the enterprises of the city of Norilsk on the vegetation cover of adjacent territories was revealed. The categories of resistance of some plant species and communities to technogenic loads have been ascertained. The protective role of overmoistening of habitats was observed for plants. 相似文献