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181.
北京翠湖湿地生境恢复及效果评估 总被引:1,自引:0,他引:1
湿地恢复是指通过生态技术或生态工程对退化或消失的湿地进行修复或重建,再现退化前的结构和功能以及相关的物理、化学和生物学特性,使其发挥应有的作用。自2010年,翠湖湿地综合运用了微地形重塑、基质恢复、植被种植和岸带护坡等湿地生境恢复技术,累计应用面积约13.33 hm2。翠湖湿地应用生境恢复技术之后,有效改善了水环境质量,血红裸藻"水华"现象爆发频率显著降低,水华覆盖面积得到有效控制。同时,湿地基质质量得到了有效提升。湿地植被覆盖度由恢复之前的51%增加到恢复后的71%;植物物种由221种增加为236种;水鸟种类和偶见种有所增加。本研究可为城市湿地恢复提供技术支撑。 相似文献
182.
以2011年3月10日云南盈江5.8级等4组5次地震为主要对象,深入分析灾害损失评估和恢复重建规划编制涉及的地震烈度调查与恢复重建范围,失去住所人数与灾后过渡性安置人数,以及民房、教育、卫生、市政、电力、通信、水利等破坏与恢复重建的规模,探讨了相互间的关系,并提出建议,对科学客观合理评估地震直接灾害损失和恢复重建规划具有一定的参考价值。 相似文献
183.
《水文科学杂志》2013,58(2):363-374
Abstract Lake ?uvintas, located in southern Lithuania in the Dovin? River basin, is one of the largest lakes and oldest nature reserves in the country. However, changes in the hydrology of the Dovin? River basin, caused by large-scale land reclamation and water management works carried out in the 20th century, have resulted in a significant decrease in the biodiversity of the lake and surrounding wetlands. In order to halt the ongoing deterioration of the lake and wetlands, solutions have to be found at the basin level. Using the SIMGRO model, various measures were therefore analysed to evaluate their impact on the water management in the Dovin? River basin. The results show that it is impossible to fully restore the water dynamics and flow pattern in the Dovin? River to their original state. However, a good measure for improving the hydrological conditions is to block drainage ditches and remove bushes and trees from the wetlands. 相似文献
184.
《International Journal of Digital Earth》2013,6(5):434-443
Abstract Historical soil survey paper maps are valuable resources that underpin strategies to support soil protection and promote sustainable land use practices, especially in developing countries where digital soil information is often missing. However, many of the soil maps, in particular those for developing countries, are held in traditional archives that are not easily accessible to potential users. Additionally, many of these documents are over 50 years old and are beginning to deteriorate. Realising the need to conserve this information, the Joint Research Centre (JRC) and the ISRIC-World Soil Information foundation have created the European Digital Archive of Soil Maps (EuDASM), through which all archived paper maps of ISRIC has been made accessible to the public through the Internet. The immediate objective is to transfer paper-based soil maps into a digital format with the maximum possible resolution and to ensure their preservation and easy disclosure. More than 6,000 maps from 135 countries have been captured and are freely available to users through a user-friendly web-based interface. Initial feedback has been very positive, especially from users in Africa, South America and Asia to whom archived soil maps were made available to local users, often for the first time. Link: http://eusoils.jrc.ec.europa.eu/library/maps/country_maps/list_countries.cfm 相似文献
185.
《自然地理学》2013,34(6):519-533
In the Midwest, the oak savanna is a unique plant community located between the western prairies and northern forests, but, once the most common plant community in Wisconsin, it is now one of the region's rarest plant communities. To assess the success of varying intensities of management practices, standard dendrochronology and vegetation surveying methods were used to determine the age structure and species composition in oak savanna sites that varied from intensely managed to unmanaged. Size and age distributions revealed that the number of distinct cohorts of oaks increased in less managed sites. Seedlings and saplings were present in high frequencies in all sites; however, management practices such as fire applications that were too frequent apparently decreased oak survivorship, as did the competition in the closed canopies of the unmanaged sites. A fire frequency of 2-3 years eliminates competition, but a frequency of 4-6 years, typical of fire-adapted forest communities, allows for slower-growing species and younger oaks to survive, while still maintaining a low density. In these conditions, where growth rates vary in time, the use of dendrochronology is necessary to obtain an accurate canopy structure for fire-adapted forest communities. Quercus macrocarpa was dominant in the more managed sites, but shade-tolerant species were dominant in the unmanaged site. At present, the canopy composition in the managed sites represented an oak savanna assemblage; however, the unmanaged composition was shifting to a woodland assemblage. Thus, remnant oak savanna can be over- or under-managed, and unmanaged oak savanna can be overlooked as woodlands. 相似文献
186.
This study aims to monitor the forest cover of Pichavaram mangroves, South India over a period of 40 years using remote sensing, and to record the status of mangroves as perceived by the local community. Out of 1471 ha of total reserved forest area, mangroves occupy 906 ha. The remote sensing maps show that there was a loss of 471 ha from 1970 to 1991 and a gain of 531 ha in 2011. Nearby 20 hamlets depend on mangroves for their livelihood. A village survey conducted at Pichavaram shows that more than 90% of the local community is well aware of the prevailing species, their importance especially after the 2004 tsunami and the impact of management practices, increased rainfall and contribution of local community in the recent increased area of mangroves. The same can be noticed from the high-resolution IKONOS image showing the artificial canal network in the restored region and from rainfall records. 相似文献
187.
The urgency of restoring ecosystems to improve human wellbeing and mitigate climate and biodiversity crises is attracting global attention. The UN Decade on Ecosystem Restoration (2021–2030) is a global call to action to support the restoration of degraded ecosystems. And yet, many forest restoration efforts, for instance, have failed to meet restoration goals; indeed, they worsened social precarities and ecological conditions. By merely focusing on symptoms of forest loss and degradation, these interventions have neglected the underlying issues of equity and justice driving forest decline. To address these root causes, thus creating socially just and sustainable solutions, we develop the Political Ecology Playbook for Ecosystem Restoration. We outline a set of ten principles for achieving long-lasting, resilient, and equitable ecosystem restoration. These principles are guided by political ecology, a framework that addresses environmental concerns from a broadly political economic perspective, attending to power, politics, and equity within specific geographic and historical contexts. Drawing on the chain of explanation, this multi-scale, cross-landscapes Playbook aims to produce healthy relationships between people and nature that are ecologically, socially, and economically just – and thus sustainable and resilient – while recognizing the political nature of such relationships. We argue that the Political Ecology Playbook should guide ecosystem restoration worldwide. 相似文献
188.
海水入侵导致地下水变咸对青岛李哥庄地区经济发展产生了不利影响,急需开展治理该地区咸水体的工作。根据研究区已有的降雨、蒸发及水文地质等资料,结合现场调查和监测,利用地下水模拟软件Visual-MODFLOW中的SEAWAT模块建立了该地区的数值模型,并利用实测资料识别和验证了该模型参数,表明所建模型能反映李哥庄地区的实际水文地质条件。为了模拟研究区地下咸水体的恢复治理情况,提出了连续抽水、间歇式抽水和抽注水结合三种咸水恢复方案,并利用该模型对三种恢复方案进行了模拟优化。结果表明,抽取地下咸水只是咸水恢复的一个因素,周边淡水的驱替作用则是咸水恢复另一个的因素,抽注水结合恢复方案为三种方案中最优的方案。 相似文献
189.
"5·12"大地震后,茂县牟托地区的地形地貌和生态系统受到很大的破坏。本文对茂县牟托地区典型斜坡的植物生长状况、土壤颗粒组成、土壤含水率进行了调查分析,获得了土壤颗粒大小、渗透性、含水率与植物生长之间的关系;研究表明,土壤颗粒组成中,细颗粒所占比例越高,其渗透系数越小,土壤含水率越大,植物的生长状况愈佳;土壤细颗粒所占比例相近的情况下,含水率高的地区植物生长好。根据研究成果,结合生态恢复的技术和方案实施的安全性以及可行性,提出水泥喷灌、修筑挡水阶梯和排水沟、种植植物等生态恢复的方案以及保持斜坡稳定的措施。 相似文献
190.