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71.
This paper examines the integration of landscape connectivity and ecosystem services. It is based on the assumption that if a habitat within a landscape has a more significant role in connecting with other habitats, it would have a higher ecosystem services value for biodiversity conservation. The Shenzhen River watershed, a cross-border region shared by the city of Shenzhen and the Hong Kong Special Administrative Region in China, was used as a case study. An area-based functional connectivity index, known as the possibility of connectivity (PC), was implemented to examine the temporal and spatial dynamics of the value of ecosystem services for biodiversity conservation over the period from 1988 to 2008. To evaluate the effectiveness of the PC index, a comparison was made between the conventional assessment method for ecosystem services and the proposed method. Results suggest that our proposed method can identify significant reduction of ecosystem services that was not only due to the decrease of habitat size, but also caused by the damage of connectivity among habitat patches. Also, it can identify sites which should have a high priority in restoring the ecosystem services for biodiversity conservation. In conclusion, this study provides a way to consider landscape connectivity in the evaluation of ecosystem services which is essential for landscape planning and nature conservation. 相似文献
72.
Data resources and assessment frameworks are two keys to ecosystem health assessment (EHA). Application of the land use database together with the Pressure–State–Response (PSR) model in EHA provides better precision relative to traditional data resources and assessment frameworks for EHA at the county scale. The raw data are taken from The Anlu County Annals, The Soil Records of Anlu County, and The Statistical Yearbook of National Economy in Anlu County. The spatial and attribute data are partly extracted from the database of current land use in Anlu City using the MAPGIS platform. Based on the results from principal component analysis (PCA), a total of eleven indicators were selected to build an indicator system designed to assess the ecosystem health at the county scale. According to the PSR model, the scores from three indices (press index, state index, and response index) and a comprehensive assessment index (CAI) were calculated, and an assessment map was constructed. The results from the index scores and spatial analysis display a large range for the state of ecosystem health due to the evolution of natural ecosystems and human activities at the county scale. The precision of the current land use database (scale of 1:10,000) makes it a better candidate for evaluating ecosystem health than the traditional data resources. This study also demonstrates the numerous benefits of combining land use databases with GIS functions to assess ecosystem health at the county scale. 相似文献
73.
S. Widdicombe A. Beesley J.A. Berge S.L. Dashfield C.L. McNeill H.R. Needham S. Øxnevad 《Marine pollution bulletin》2013
A mesocosm experiment was conducted to quantify the relationships between the presence and body size of two burrowing heart urchins (Brissopsis lyrifera and Echinocardium cordatum) and rates of sediment nutrient flux. Furthermore, the impact of seawater acidification on these relationships was determined during this 40-day exposure experiment. Using carbon dioxide (CO2) gas, seawater was acidified to pHNBS 7.6, 7.2 or 6.8. Control treatments were maintained in natural seawater (pH ≈ 8.0). Under normocapnic conditions, burrowing urchins were seen to reduce the sediment uptake of nitrite or nitrate whilst enhancing the release of silicate and phosphate. In acidified (hypercapnic) treatments, the biological control of biogeochemical cycles by urchins was significantly affected, probably through the combined impacts of high CO2 on nitrifying bacteria, benthic algae and urchin behaviour. This study highlights the importance of considering biological interactions when predicting the consequences of seawater acidification on ecosystem function. 相似文献
74.
《水文科学杂志》2013,58(3):526-537
Abstract The study of the Continental Intercalaire aquifer system of southern Tunisia, based on the interpretation of geochemical (major elements) and isotopic (18O, 2H, 13C and 14C) data, has aided the understanding of the hydrodynamics of this multi-layer aquifer system, which is greatly influenced by tectonics. The determination of the origin of groundwater salinization and the understanding of the hydrogeological and geochemical behaviour of this aquifer were achieved by studying the correlation between the major elements and total mineralization (TDS). By using isotopic tools, it was shown that the water of this aquifer has been recharged under cooler, palaeoclimatic conditions. The technique also made it possible to better understand the hydrodynamic functioning of the aquifer system: it showed that the relatively recent recharge of the aquifer has been by direct infiltration from carbonate and sandy outcrops of the Cretaceous and Miocene, respectively, located in the eastern and northeastern parts of the aquifer. The 18O content was used to calculate the altitude of recharge basins. The isotopic gradient defined in this study is ?0.5 δ18O ‰/100 m. 相似文献
75.
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
76.
77.
Previous studies on heavy metal contamination of the Baie des Chaleurs focus only on industrial centers and overlooked the ecosystem as a whole. To fill this gap, the objective of this study is to establish a baseline of the spatio-temporal distribution of heavy metals in mussels from the Baie des Chaleurs based on the ecosystem approach. Our results show, for the first time, a cadmium contamination in mussels across the south coast of the Baie des Chaleurs and not only in industrial centers. Our results also confirm previous studies showing heavy metal contamination of the Belledune area. This study demonstrates that the use of the ecosystemic approach is essential to obtain a comprehensive picture of environmental contamination in marine ecosystems. 相似文献
78.
79.
土地利用变化对延安市生态服务价值的影响 总被引:2,自引:0,他引:2
利用延安市2001-2007年土地利用基础数据,计算土地利用动态度,并在Costanza生态系统服务价值理论基础上,结合谢高地等的中国生态系统生态服务价值当量因子表,计算出延安不同生态系统单位面积生态服务价值。并依此尝试计算延安市2001年至2007年延安市生态系统服务价值量。研究发现,2007延安市的生态系统服务价值将达到424.28亿元,比2001年增加28.79亿元,增长率为7.28%;各种土地利用方式的生态系统服务价值的敏感性指数(CS)均小于1,表明其对生态系统的价值变化是缺乏弹性的。 相似文献
80.