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Forests of Greece, Their Multiple Functions and Uses, Sustainable Management and Biodiversity Conservation in the Face of Climate Change 被引量:1
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作者 Konstantinos A. Spanos Asimina Skouteri +6 位作者 Dionysios Gaitanis Panos V. Petrakis Ioannis Meliadis Panagiotis Michopoulos Alexandra Solomou Panagiotis Koulelis Evangelia V. Avramidou 《Open Journal of Ecology》 2021年第4期374-406,共33页
This is a review paper based on national and international literature, national inventories and empirical approach. A general overview of the forests, forest management and forest biodiversity of Greece are briefly su... This is a review paper based on national and international literature, national inventories and empirical approach. A general overview of the forests, forest management and forest biodiversity of Greece are briefly summarized. The distribution of the main forest species and their ecosystems in the Geographic regions of Greece is presented in a tabular form. Their multiple functions and uses, their management type/regime, their risks and threats, protection and conservation measures are also synoptically described. Furthermore, adaptive forest management and silviculture as well as management of genetic diversity in order to face climate change are also analysed. Research priority areas on biodiversity and challenges for biodiversity research and related policy in Greece have been summarized. The new Rural Development Program (2014-2020), which is currently in the final phase of implementation, will take into consideration the forest itself and forest-related European and National legal obligations. Finally, major conclusions and research priority areas on future management and conservation of forests are highlighted. 展开更多
关键词 Greece FORESTS Multiple uses management BIODIVERSITY CONSERVATION Forest Policy Climate change Strategic Targets
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Land Use/Cover and Naturalness Changes for Watershed Environmental Management(Southeastern Brazil)
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作者 Romulo Theodoro Costa Camila Francisco Goncalves +1 位作者 Angela Terumi Fushita José Eduardo dos Santos 《Journal of Geoscience and Environment Protection》 2017年第11期1-14,共14页
Driving forces on the landscape require regional management and/or local actions, together with other external factors. To operationalize this approach, this paper carried out a comparative analysis of the naturalness... Driving forces on the landscape require regional management and/or local actions, together with other external factors. To operationalize this approach, this paper carried out a comparative analysis of the naturalness dynamics of the Jacaré-Gua&#231u and Jacaré-Pepira watershed, based on land use/cover changes and a structural indicator of the landscape, over the 10-year (2004-2014), as support opportunities for improving its environmental planning and management. Land use/cover dynamics were obtained based on screen digitizing of LandSat imagery, using polygon manual digitalization. Naturalness scenarios of the watersheds, over the 10-year (2004-2014), were obtained based on Urbanity Indicator, which evaluates how much the natural landscapes are dominated by altered systems. The total area of watersheds showed a predominantly scenario, induced by anthropogenic agricultural and non-agricultural expansion areas, mainly by conversion of other land use/cover types in sugarcane cultivation. Despite the increase in natural vegetation areas, over the 10-year (2004-2014), Jacaré-Gua&#231u and Jacaré-Pepira watersheds are far from a sustainable condition. However Jacaré-Gua&#231u watershed presents a scenario of more committed naturalness due to the increase in Urbanity Index values ≥ 0.7. The historical process of land use occupation for agricultural production remains the main driving force of naturalness changes, occupying more than 70% of the total area of watersheds. These results have significant implications for fast urbanizing municipalities in providing key information about long term land use impact on the watershed structure and function, making it possible for policy makers, scientists and stakeholders to identify land uses which are hindered or enhanced under various scenarios of land use change over the time, and making it possible to explore the trade-offs between them to improve watershed management. 展开更多
关键词 Land use changes Urbanity Index Loss Natural Capital Watershed Sustainable management
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Forces Driving Changes in Cultivated Land and Management Countermeasures in the Three Gorges Reservoir Area,China 被引量:15
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作者 CAO Yin-gui BAI Zhong-ke +1 位作者 ZHOU Wei WANG Jing 《Journal of Mountain Science》 SCIE CSCD 2013年第1期149-162,共14页
The Three Gorges project accelerates economic development in the Three Gorges Reservoir Area.This paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces dri... The Three Gorges project accelerates economic development in the Three Gorges Reservoir Area.This paper aimed to investigate the distribution,changes and features of cultivated land in this area,analyze the forces driving the changes in cultivated land area,and propose the countermeasures for cultivated land management.Transition matrix was used to analyze the features of cultivated land changes,and quantitative analysis and qualitative analysis were adopted to research the driving forces according to the features of cultivated land changes.Cultivated land in the Three Gorges Reservoir Area mainly lay to the northwest of the Yangtze River,especially the upper reaches.The areas of cultivated land increased from 1996 to 1999,then decreased from 2000 to 2006,and finally increased again from 2007 to 2009.The important forces driving changes in cultivated land included government policies,employment and food security,increasing construction land,agriculture structure adjustment,land rearrangement,inundation.During cultivated land management,firstly,it is necessary to insist on the principle of cultivated land protection,standardize land exploitation and strictly restrict the transformation of cultivated land into non-farming land.Secondly,land rearrangement must be implemented,which can not only increase the area of the cultivated land,but also improve the quality of the cultivated land.Thirdly,it is feasible to intensify eco-agriculture construction to increase the quantity and quality of cultivated land.Fourthly,it is helpful to improve the traditional agriculture production methods to promote cultivated land quality.Lastly,it is important to propagandize cultivated land protection and realize the enormous pressure of cultivated land shortage,making more people obligated to protect cultivated land. 展开更多
关键词 Land use change Driving force management countermeasure Cultivated land Three Gorges Reservoir Area
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Shrinking greenery: Land use and land cover changes in Kurram Agency, Kohi Safid Mountains of north-western Pakistan 被引量:2
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作者 Kamal HUSSAIN Fazlul HAQ Fazlur RAHMAN 《Journal of Mountain Science》 SCIE CSCD 2018年第2期296-306,共11页
Deforestation and other Land Use and Land Cover(LULC) changes, driven by variety of physical and anthropogenic factors, have altered the mountainous environment. Mountains around the world including northern and north... Deforestation and other Land Use and Land Cover(LULC) changes, driven by variety of physical and anthropogenic factors, have altered the mountainous environment. Mountains around the world including northern and north western belts of Pakistan are highly sensitive to deforestation and other LULC changes, which have profound impacts on various sectors of bio-physical and socio-economic systems. Assessment of LULC changes has high significance for protection, conservation and monitoring mountainous environment. The present study is an attempt to assess the landscape changes with particular reference to forest cover depletion in Kurram Agency located in the north western mountain belt of Pakistan. For detailed comparative analysis the study area has been divided into three sections, which coincide with the present administrative divisions of the Agency, i.e., Upper,Lower and Central Kurram. Temporal span of this study covers four decades. In this study, land use map of 1970 and land sat satellite imageries of 1987, 2000 and 2014 were used as spatial data sets. The images were processed and classified into six LULC classes through geospatial packages and change detection maps were prepared for each division and time period.Findings of the study reveal two trends in the four major LULC categories. Forest and rangeland have shrunk, on average, by 15% and 7.5% respectively while, bare soil and rocks outcrops have expanded by 89% and agriculture land by 7.2% in Kurram agency.The water bodies and snow cover have minor fluctuation in its land area. Major causes of shrinking greenery is attributed to high influx of Afghan refugees and high energy demand of growing population. However, with outflow of the refugees from Kurram agency the general trend in forest cover has reverted and deforestation rate has slowed down. 展开更多
关键词 Pakistan Tribal areas DEFORESTATION Land use Land Cover change Resource management Global changes
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Historical Land Use/Cover Changes and the Hemeroby Levels of a Bio-Cultural Landscape: Past, Present and Future 被引量:2
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作者 Angela Terumi Fushita José Eduardo dos Santos +1 位作者 Yuri Tavares Rocha Elisabete Maria Zanin 《Journal of Geographic Information System》 2017年第5期576-590,共15页
The urbanization of a campus landscape has required much space for this expansion, reinforcing the status of geographical space as a limited resource. We analyzed the effects of land cover change assessed over tempora... The urbanization of a campus landscape has required much space for this expansion, reinforcing the status of geographical space as a limited resource. We analyzed the effects of land cover change assessed over temporal dataset on composition and configuration dynamics of UFSCar (Federal University of S&#227;o Carlos) campus landscape, based on a descriptive view of the hemeroby levels, over a 54-year period (1962-2016), in order to understand the impacts of past anthropogenic induced landscape change and inform decision making with regard to biodiversity management. The classification of land use/cover dynamics, over time, was obtained based on screen digitizing of aerial photos and LandSat imagery. An ordinal scale ranging from ahemerob to metahemerob was applied to assess the hemerobiotic state of each land use type. Currently, The UFSCar landscape campus configures a biocultural mosaic in different stages of hemeroby. Thus a campus landscape dynamics model, which can be denoted as “forestry-conservation-urban model”, anthropogenic landscape is replaced by natural one, later by land cover reflecting the spatial anthropization process. Through time, two hemerobiotic trajectories were identified, in which 1) an euhemerob landscape matrix is substituted by an ahemerob one, resulting in increased naturalness of the campus landscape, and then 2) metahemerob patch types will later on increasing as a consequence of ongoing urbanization. Expressive amount of ahemerob patches in campus landscape fulfills one of the conditions for maintenance of the capacity for self-regulation and sustainability of a biocultural landscape. This framework provides an essential tool supporting with essential information about current and historical landscape sustainability for campus landscape management and support decision making process. The main institutional challenge for campus landscape sustainable management lies in the balance between the competitors of the campus landscape matrix: conservation x urbanization. 展开更多
关键词 Land use change Trajectories URBANIZATION CONSERVATION LANDSCAPE Sustainable management
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Changes in Agricultural Biodiversity: Implications for Sustainable Livelihood in the Himalaya 被引量:7
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作者 K.G.Saxena R.K.Maikhuri K.S.Rao 《Journal of Mountain Science》 SCIE CSCD 2005年第1期23-31,共9页
Himalayan mountain system is distinguished globally for a rich biodiversity and for its role in regulating the climate of the South Asia. Traditional crop-livestock mixed farming in the Himalaya is highly dependent on... Himalayan mountain system is distinguished globally for a rich biodiversity and for its role in regulating the climate of the South Asia. Traditional crop-livestock mixed farming in the Himalaya is highly dependent on forests for fodder and manure prepared from forest leaf litter and livestock excreta. Apart from sustaining farm production, forests provide a variety of other tangible and intangible benefits, which are critical for sustainable livelihood of not only 115 million mountain people, but also many more people living in the adjoining plains. Extension of agricultural land- use coupled with replacement of traditional staple food crops by cash crops and of multipurpose agroforestry trees by fruit trees are widespread changes. Cultivation of Fagopyrum esculentum, Fagopyrum tataricum, Panicum miliaceum, Setaria italica and Pisum arvense has been almost abandoned. Increasing stress on cash crops is driven by a socio-cultural change from subsistence to market economy facilitated by improvement in accessibility andsupplyofstaplefoodgrainsatsubsidizedpriceby the government. Farmers have gained substantial economic benefits from cash crops. However, loss of agrobiodiversity implies more risks to local livelihood in the events of downfall in market price/demand of cashcrops,terminationofsupplyofstaplefoodgrains at subsidized price, pest outbreaks in a cash crop dominated homogeneous landscape and abnormal climate years. Indigenous innovations enabling improvement in farm economy by conserving and/enhancing agrobiodiversity do exist, but are highly localized. The changes in agrobiodiversity are such that soil loss and run-off from the croplands have dramatically increased together with increase in local pressure on forests. As farm productivity is maintained with forest-based inputs, continued depletion of forest resources will result in poor economic returns from agriculture to local people, apart from loss of global benefits from Himalayan forests. Interventions including improvement in traditionalmanureandmanagementofon-farm trees, participatorydevelopmentofagroforestryindegraded forestlandsandpoliciesfavoringeconomicbenefitsto local people from non-timber forest products could reduce the risks of decline in agricultural biodiversity and associated threats to livelihoods and Himalayan ecosystems. 展开更多
关键词 Land use/cover change food security cash crops traditional agricultural practices forest management
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Long-term variations in runoff of the Syr Darya River Basin under climate change and human activities 被引量:3
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作者 Sanim BISSENBAYEVA Jilili ABUDUWAILI +1 位作者 Assel SAPAROVA Toqeer AHMED 《Journal of Arid Land》 SCIE CSCD 2021年第1期56-70,共15页
In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human a... In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human activities on river runoff.The Syr Darya River,which is supplied by snow and glacier meltwater upstream,is an important freshwater source for Central Asia,as nearly half of the population is concentrated in this area.River runoff in this arid region is sensitive to climate change and human activities.Therefore,estimation of the climatic and hydrological changes and the quantification of the impacts of climate change and human activities on river runoff are of great concern and important for regional water resources management.The long-term trends of hydrological time series from the selected 11 hydrological stations in the Syr Darya River Basin were examined by non-parametric methods,including the Pettitt change point test and Mann-Kendall trend tests.It was found that 8 out of 11 hydrological stations showed significant downward trends in river runof f.Change of river runoff variations occurred in the year around 1960.Moreover,during the study period(1930–2015),annual mean temperature,annual precipitation,and annual potential evapotranspiration in the river basin increased substantially.We employed hydrological sensitivity method to evaluate the impacts of climate change and human activities on river runoff based on precipitation and potential evapotranspiration.It was estimated that human activities accounted for over 82.6%–98.7%of the reduction in river runoff,mainly owing to water withdrawal for irrigation purpose.The observed variations in river runoff can subsequently lead to adverse ecological consequences from an ecological and regional water resources management perspective. 展开更多
关键词 river runoff variations water resources management land use/land cover changes Mann-Kendall trend test hydrological sensitivity analysis Aral Sea Central Asia
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Vulnerability of Himalayan springs to climate change and anthropogenic impact: a review
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作者 Sugandha PANWAR 《Journal of Mountain Science》 SCIE CSCD 2020年第1期117-132,共16页
The climate change and unsustainable anthropogenic modification can intensify the vulnerability of the Himalayas. Natural springs are the principal source of potable water security for the Himalayan population. The ch... The climate change and unsustainable anthropogenic modification can intensify the vulnerability of the Himalayas. Natural springs are the principal source of potable water security for the Himalayan population. The changes in the trend of precipitation, temperature and glacier melt are expected to impact the quantity and quality of spring water significantly. This review presents an insight to unravel the effects of climate change and land use land cover changes on the spring resources and outline the essential elements of spring hydrology in the Himalayas. The sensitive response of spring flow to the climate has been observed to follows an annual periodic pattern strongly dependent on snowmelt,rainfall, and evapotranspiration. Among all types,Karst aquifers were found to be highly vulnerable. The changes in the forest and urban landscapes are affecting the recharging sites in the headwater region.In the Central Himalayan region(Kosi River basin,Kumaun), the number of perennial springs is decreasing at a rate of three springs year-1, and nonperennial springs are increasing at the rate of one spring year-1. The high concentration of NO3-, Cl-1,SO42-, and coliform counts reported from the spring water evidence a high susceptibility of shallow aquifers to the non-point source of pollution. Future projections indicate high surface-runoff and occurrence of extreme events such as floods, glacial lake outbursts, and landslides can affect the flow and water quality of springs. As the impact of climate change and anthropogenic activities are expected to increase with time remarkably, there is an urgent need to promote regional scientific studies on springs targeting hydrogeochemical evolution, vulnerability assessment, recharge area dynamics, and development of springshed management program. 展开更多
关键词 Himalayan springs Climate change Land use land cover changes Spring management
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DROUGHT DISASTERS AND ENVIRONMENTAL CHANGE DURING PAST 30 YEARS IN AFRICA
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作者 Ding Dengshan(Dept. of Geo. & Ocean Sciences, Nanjing University, Nanjing 210093PePle’s RePublic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第1期92-100,共9页
A number of very serious drough disasters occurred in many regions of Aftica during past 30 years. It is commonly considered that they are among the most serious disasters after the World War II. The basic situation o... A number of very serious drough disasters occurred in many regions of Aftica during past 30 years. It is commonly considered that they are among the most serious disasters after the World War II. The basic situation of the droughs and drough disasters are introduced briefly, and the main causes resulting 1i drought disasters are analysed in the paper. The lack of rainfall is one of the factors producing the drough disasters in Africa, but it is not the real one. From environmental viewpoints, the drough disasters in Africa resulted from unsuitable land use and management by man, and in essence they are the results of man-made environmental disturbance. Finally, the strategy for preventing drought disasters in Africa is suggested. 展开更多
关键词 drought disasters environmental change land use and management
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The Effect of Land Cover Change on Flooding in Texas
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作者 Seong Nam Hwang 《Journal of Geoscience and Environment Protection》 2017年第9期123-137,共15页
The world population has been increasing while, similarly, both the number of environmental disasters and the loss resulting from those have been on the rise. It is also expected that the trend will continue. Especial... The world population has been increasing while, similarly, both the number of environmental disasters and the loss resulting from those have been on the rise. It is also expected that the trend will continue. Especially, what is noticeable is that more and more people and property concentrate on cities. In fact, urbanization is a major global trend simply because most people want to get their jobs, raise and educate their children, and enjoy riches of diverse cultures, recreation activities, and entertainment, which cities can provide to them. Urbanization always involves transforming the natural environment into a man-made environment, contributing to changes in land use and land cover patterns as well as in landscape and hydrology in the built-up areas. These changes, in turn, negatively influence the natural environment because those changes almost always tend to result in the disruption of its fragile ecosystems in balance. In addition, the changes mean the land used, for example, for a natural ecosystem may be converted into an impervious land, which can increase human vulnerability to floods, causing human and property losses. There has been some research done to investigate the relationship between land use/land cover change and environmental hazards. However, little research has been conducted to test direct effects of land cover change on environmental disasters such as floods, hurricanes, and hazardous material releases by using GIS and remote sensing technologies. Therefore, this research aimed to analyze the effect of land cover change on floods. More specifically, the research tested whether land cover change is related to flood disasters in Texas from 1993 to 2012. One of the main findings of this research is that both decrease in forest areas and increase in urban built-up areas contributed to the property damage resulting from flood events. 展开更多
关键词 DISASTER MITIGATION Environmental HAZARD LAND use change EMERGENCY management DISASTER Planning FLOODING
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优势物种对内蒙古典型草原营养物质生产的决定性影响
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作者 王若冰 王永慧 +1 位作者 赵宏宇 张斌 《草业科学》 CAS CSCD 北大核心 2024年第9期2012-2024,共13页
草地通过提供粗蛋白、粗脂肪、中性洗涤纤维和酸性洗涤纤维等营养物质而支撑畜牧业发展,但也受到干旱化的气候及日益增强的放牧和刈割活动的威胁。基于为期3年的内蒙古典型草原草地管理模式和降水量改变控制试验,本研究发现其营养物质... 草地通过提供粗蛋白、粗脂肪、中性洗涤纤维和酸性洗涤纤维等营养物质而支撑畜牧业发展,但也受到干旱化的气候及日益增强的放牧和刈割活动的威胁。基于为期3年的内蒙古典型草原草地管理模式和降水量改变控制试验,本研究发现其营养物质生产能力随降水量减少而降低。尽管放牧和刈割的影响弱于降水量,但仍可通过降低群落生产力而降低其营养物质生产能力。此外,羊草(Leymus chinensis)和克氏针茅(Stipa krylovii)等优势物种的营养物质含量和群落生产力贡献调控群落营养物质生产能力对降水量和草地管理模式变化的响应。这意味着,干旱化的气候会降低内蒙古典型草原优势物种营养物质供给能力,从而降低群落营养物质生产,威胁畜牧业的可持续发展,而日益增强的放牧和刈割活动会使其进一步恶化。 展开更多
关键词 内蒙古典型草原 气候变化 草地管理模式变化 补偿效应 选择效应
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Assessment of land use change and its effect on soil carbon stock using multitemporal satellite data in semiarid region of Rajasthan, India 被引量:2
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作者 Garima Sharma L.K.Sharma K.C.Sharma 《Ecological Processes》 SCIE EI 2019年第1期513-529,共17页
Background:Land use change plays a vital role in global carbon dynamics.Understanding land use change impact on soil carbon stock is crucial for implementing land use management to increase carbon stock and reducing c... Background:Land use change plays a vital role in global carbon dynamics.Understanding land use change impact on soil carbon stock is crucial for implementing land use management to increase carbon stock and reducing carbon emission.Therefore,the objective of our study was to determine land use change and to assess its effect on soil carbon stock in semi-arid part of Rajasthan,India.Landsat temporal satellite data of Pushkar valley region of Rajasthan acquired on 1993,2003,and 2014 were analyzed to assess land use change.Internal trading of land use was depicted throughmatrices.Soil organic carbon(SOC)stock was calculated for soil to a depth of 30 cm in each land use type in 2014 using field data collection.The SOC stock for previous years was estimated using stock change factor.The effect of land use change on SOC stock was determined by calculating change in SOC stock(t/ha)by deducting the base-year SOC stock from the final year stock of a particular land use conversion.Results:The total area under agricultural lands was increased by 32.14%while that under forest was decreased by 23.14%during the time period of 1993–2014.Overall land use change shows that in both the periods(1993–2003 and 2003–2014),7%of forest area was converted to agricultural land and about 15%changes occurred among agricultural land.In 1993–2003,changes among agricultural land led to maximum loss of soil carbon,i.e.,4.88 Mt C and during 2003–2014,conversion of forest to agricultural land led to loss in 3.16 Mt C.Conclusion:There was a continuous decrease in forest area and increase in cultivated area in each time period.Land use change led to alteration in carbon equity in soil due to change or loss in vegetation.Overall,we can conclude that the internal trading of land use area during the 10-year period(1993–2003)led to net loss of SOC stock by 8.29 Mt C.Similarly,land use change during 11-year period(2003–2014)caused net loss of SOC by 2.76 Mt C.Efforts should be made to implement proper land use management practices to enhance the SOC content. 展开更多
关键词 Multitemporal satellite data Land use change dynamics Internal trading of land use SOC stock Stock change factor change in SOC pool Land use management
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Analysis of coastal land use/land cover changes in the Indian Sunderbans using remotely sensed data 被引量:2
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作者 Debajit DATTA Shovik DEB 《Geo-Spatial Information Science》 SCIE EI 2012年第4期241-250,共10页
The world’s largest mangrove ecosystem,the Sunderbans is experiencing multidimensional threats of degradation.The present study was aimed to understand these problems and search for proper remedies by applying suitab... The world’s largest mangrove ecosystem,the Sunderbans is experiencing multidimensional threats of degradation.The present study was aimed to understand these problems and search for proper remedies by applying suitable remote sensing technologies.South-western parts of Indian Sunderbans Biosphere Reserve had been chosen for assessment of land use/land cover changes in between 1975 and 2006 by using multitemporal Landsat data.Results indicated considerable reduction of open mangrove stands and associated biodiversity mainly in the forest-habitation interference zones of Sunderbans.On the contrary,increase in the coverage of dense mangroves in the reserved forests had been observed indicating the existence of proper centralized management regimes.Overall,a cumulative loss of approximately 0.42%of its original mangrove cover in between 1975 and 2006 had been estimated for this part of the Sunderbans which was at parity with the findings of other studies in the Sunderbans or similar mangrove ecosystems of the tropics.Expansion of non agricultural lands in the last two decades was found to be related with the growth of new settlements,tourism infrastructure,and facilities.This transformation was attributed to the shifting of local peoples’interest from traditional forestry and subsistence farming towards alternative occupations like shrimp culture,coastal tourism,and commercial fishing although environmentally hazardous livelihood activities like collection of prawn seeds along the riverbanks were still persistent. 展开更多
关键词 sustainable mangrove management landsat data land use/land cover changes
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Managed grassland alters soil N dynamics and N2O emissions in temperate steppe 被引量:2
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作者 Lijun Xu Xingliang Xu +7 位作者 Xuejuan Tang Xiaoping Xin Liming Ye Guixia Yang Huajun Tang Shijie Lv Dawei Xu Zhao Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期20-30,共11页
Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen(N) dynamics and nitrous oxide(N2O) emissions. However, it ... Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen(N) dynamics and nitrous oxide(N2O) emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil(0-10 cm), nitrate(NO3-),ammonium(NH4+), and microbial N were measured in plots in a temperate steppe(Leymus chinensis grassland) and two managed grasslands(Medicago sativa and Bromus inermis grasslands) in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4-N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa(i.e., a legume grass) increased N2O emissions by 26.2%, while the conversion to the B. inermis(i.e., a non-legume grass) reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3-+-N and NH4-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions. 展开更多
关键词 Temperate steppe managed grassland Land use Nitrogen mobility N2O emissions
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Identification of Groundwater Potential Zones in Samendeni Watershed in Sedimentary and Semi-Arid Contexts of Burkina Faso, Using Analytic Hierarchy Process (AHP) Method and GIS
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作者 Sadraki Yabre Youssouf Koussoubé +2 位作者 Sauret Élie Serge Gaëtan Nicaise Yalo Stephen Silliman 《American Journal of Climate Change》 2023年第1期172-203,共32页
Demand for water increases in Samendeni regarding the undertaken agricultural projects while pressure on surface water from global warming/evapotranspiration also increases. Thus, the need to evaluate the groundwater ... Demand for water increases in Samendeni regarding the undertaken agricultural projects while pressure on surface water from global warming/evapotranspiration also increases. Thus, the need to evaluate the groundwater potential in the catchment is crucial as alternative supplier of water and resilience to climate hazards. The AHP was performed integrating ten influencing factors such as geomorphology, geology, soil, land use/land cover (lulc), slope, rainfall, drainage density, borehole rate & depth and piezometric level to generate groundwater potential zones (GWPZs) in Samendeni watershed (4420 km<sup>2</sup>). All the factors were processed and ranged into five (5) classes. Weight was assigned to each class of thematic layer. These thematic layers were then reclassified based on the normalized weight to be used in the calculation of groundwater potential zones (GWPZ). The final output, groundwater potential map, revealed a significant groundwater potential with very good (11%), good (31%), moderate (30%), poor (20%), and very poor (8%) of proportion. The interesting (very good, good) GWPZs in the study area are mostly in the central towards the east. The poor zones in term of groundwater potential are concentrated in the upper west region of the watershed. Besides the cross-validation with the relationship between different groundwater potential zones and the wells available in the study area, the overall accuracy was estimated to 88% provided from the result of the similarity analysis where 22 out of the 25 validation wells match with the expected yield classes of GWPZs. The statistics from that validation revealed the performance of AHP method to delineate groundwater potential zones at catchment level. 展开更多
关键词 Climate change Resilience Groundwater Potential Water management Conjunctive use AHP GIS Samendeni Watershed
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温性草原利用方式对生态系统碳交换及其组分的影响 被引量:15
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作者 李愈哲 樊江文 +1 位作者 胡中民 邵全琴 《生态学报》 CAS CSCD 北大核心 2018年第22期8194-8204,共11页
为了解管理利用方式变化对原本以放牧利用为主的草地生态系统的碳交换及碳平衡将产生怎样的影响。在中国北方温性草原区域利用连接同化箱的便携式红外分析系统,在相互毗连的地块调查了3种典型草地管理利用方式植被生长旺季的生态系统碳... 为了解管理利用方式变化对原本以放牧利用为主的草地生态系统的碳交换及碳平衡将产生怎样的影响。在中国北方温性草原区域利用连接同化箱的便携式红外分析系统,在相互毗连的地块调查了3种典型草地管理利用方式植被生长旺季的生态系统碳交换及其精细组分。结果表明,相比放牧草地,开垦农用显著降低生态系统的日均碳交换(下降56%,P<0.05),而长期围封也趋向降低生态系统的日均碳交换,但变化并不显著(P>0.05)。与之近似,NPP在放牧与禁牧草地间差异不显著,开垦农用使NPP显著下降,但降幅小于NEP。GPP在3种管理利用方式间差异相对较小。生态系统总呼吸、自养、异养、地上和地下呼吸在放牧和禁牧草地间均无显著差异,均显著低于开垦后的麦田,根系呼吸在3种管理利用方式间无显著变化。相比草地放牧,草地开垦显著增加自养呼吸在总呼吸中的占比,而土壤呼吸和根系呼吸的占比均显著下降,禁牧对呼吸组成的影响不明显。不同管理利用方式草地的地下生物量能很好的解释土壤呼吸占比(95%)和根系呼吸占比(77%)的变化,而LAI则与自养呼吸占比显著正相关(P<0.001)。草地开垦利用增强生态系统的碳释放、减少CO_2固定,相比开垦农用,禁牧对放牧草地碳交换及其组分的影响相对较小。 展开更多
关键词 草地利用方式转变 温性草原 生态系统碳交换 呼吸及其组成
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Spatiotemporal Patterns and Drivers of Forest Change from 1985–2000 in the Beijing-Tianjin-Hebei Region of China 被引量:5
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作者 谢雪 谢花林 范员华 《Journal of Resources and Ecology》 CSCD 2016年第4期301-308,共8页
Forests are fundamental to maintaining ecological security and achieving regional sustainable development in China. Forest land change can result in many ecological problems including soil erosion, water shortages dro... Forests are fundamental to maintaining ecological security and achieving regional sustainable development in China. Forest land change can result in many ecological problems including soil erosion, water shortages drought and biodiversity loss. Based on landscape ecology and logistic regression we explored the spatiotemporal patterns and factors affecting forest land changes from 1985 to 2000 in the Beijing-Tianjin-Hebei Region of China. The results show decreased local fragmentation of woodland landscapes and that the shapes of forest patches have become more regular. For forest land cover change, soil organic matter content, slope type I (〈5°), distance to the nearest village and per capita GDP were the most important independent variables from 1985 to 2000. This study indicates that spatial heterogeneity can affect the predictability of logistic regression models for forest land change. 展开更多
关键词 forest land Land use/land Coverage change (LUCC) Logistic regression model forest management ecological security
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开垦对放牧温性草原生态系统水分利用效率的影响 被引量:5
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作者 李愈哲 邵全琴 +4 位作者 樊江文 陈一 陈智 官惠玲 张馨元 《草业学报》 CSCD 北大核心 2019年第10期110-121,共12页
作为生态系统碳水循环的耦合指标,水分利用效率(WUE)是衡量区域资源转化效率的重要参考。为了解开垦利用对放牧草地生态系统水分利用效率的影响,以放牧区域和开垦利用区域毗邻的两套涡度相关系统监测数据为基础,结合群落调查和采样测定... 作为生态系统碳水循环的耦合指标,水分利用效率(WUE)是衡量区域资源转化效率的重要参考。为了解开垦利用对放牧草地生态系统水分利用效率的影响,以放牧区域和开垦利用区域毗邻的两套涡度相关系统监测数据为基础,结合群落调查和采样测定,对比分析了两种管理利用方式下生态系统水分利用效率(WUE GPP)的动态差异和影响因素。结果显示:1)WUE GPP在夏季达到全年峰值,6月开垦站点日均WUE GPP 3.61 g C·kg-1 H 2O,较放牧站点高58%,全年WUE GPP 3.07 g C·kg-1 H 2O,较放牧站点2.11 g C·kg-1 H 2O提升约50%;2)开垦站点较高的WUE GPP归咎于生长季较高的总初级生产力(GPP)和非生长季更低的蒸散耗水(ET);3)ET变化对放牧站点WUE GPP变异解释程度较高(26%,P<0.001),而GPP对开垦站点WUE GPP变化的解释程度(45%,P<0.001)高于ET;4)环境因子中,土壤含水量对WUE GPP变化的调控作用最强,两者负相关关系在开垦站点、放牧站点均达到极显著水平(P<0.001)。研究结果能为合理规划区域土地利用,促进干旱区关键资源高效利用提供有益参考。 展开更多
关键词 草地开垦 放牧生态系统 草地利用方式转变 温性草原 水分利用效率
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长期氮素添加对内蒙古典型草原有机碳库的影响 被引量:1
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作者 康俊霞 王瑞珍 +3 位作者 寻芬 张光明 谭增涛 白文明 《中国草地学报》 CSCD 北大核心 2014年第1期79-83,共5页
于内蒙古典型草原地区开展了为期8年的长期氮素添加梯度处理实验来模拟氮沉降,研究草原生态系统地上和地下碳库对氮沉降的响应.结果表明,氮肥添加显著增加了植物活体有机碳库和凋落物碳库,而对根有机碳库的影响并不显著,对0~l0cm、l0~... 于内蒙古典型草原地区开展了为期8年的长期氮素添加梯度处理实验来模拟氮沉降,研究草原生态系统地上和地下碳库对氮沉降的响应.结果表明,氮肥添加显著增加了植物活体有机碳库和凋落物碳库,而对根有机碳库的影响并不显著,对0~l0cm、l0~20cm、20~30cm、30~70、0~70cm土层的土壤有机碳含量和土壤碳库也无明显作用.地下部分总碳库和生态系统碳库在试验期内均未随氮沉降量的增大而发生显著改变. 展开更多
关键词 有机碳库 氮沉降 典型草原 全球变化 生态系统管理
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Community Responses to Mountain Tourism:A Case in Bhyundar Valley,Indian Himalaya 被引量:6
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作者 Ram Babu Singh Suraj Mal Chandra Prakash Kala 《Journal of Mountain Science》 SCIE CSCD 2009年第4期394-404,共11页
Tourism industry has become an important part of Indian economy,and tourism development has been,however,concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the to... Tourism industry has become an important part of Indian economy,and tourism development has been,however,concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the tourism centers,which pose serious threats to the natural environment. The Bhyundar Valley of Nanda Devi Biosphere Reserve (NDBR) in Uttarakhand State of the Indian Himalaya is a burning example of such problems. Land use/cover changes,deforestation and accumulation of garbage are some of the negative impacts of unregulated tourism in the valley. Unsustainable activities of tourists and villagers in the valley make such problems very severe. To deal with the ongoing problems and ensure community involvement in tourism management and environmental conservation,the Biosphere Reserve Authority introduced ecotourism in the form of Eco Development Committees (EDCs) in the Bhyundar Valley. Study reveals that many problems associated with tourism have been minimized to some extent with the help of EDCs but few are still prevailing in valley. However,the existing attempts to conserve the valley from the negative effects of tourism are inadequate and modifications are needed in the current initiatives. 展开更多
关键词 Mountain tourism Land use change Community response Eco development committee Environmental management
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