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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 Cover Change in a Freshwater Swamp Forest Landscape: Implications for Biodiversity Conservation
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作者 Nwabueze I. Igu Joseph O. Duluora 《Journal of Environmental Protection》 2019年第12期1578-1590,共13页
Forest landscapes are under much pressure globally due to changes in land use and their biodiversity and services are threatened at increasing magnitude especially in the tropics. Biodiversity and ample forest cover s... Forest landscapes are under much pressure globally due to changes in land use and their biodiversity and services are threatened at increasing magnitude especially in the tropics. Biodiversity and ample forest cover still remain in freshwater forest landscapes in the Niger basin of Nigeria, but are declining at astronomical scales across the region. To better understand the changes and modifications going on in the ecosystem at the landscape level, a thirty-year study (1987-2017) was conducted using remotely sensed Landsat imageries. These were processed and used to verify the dynamics in land cover changes and their major drivers. Land use change across the region reduced the forest extent and forest cover (up to 50.2 percent) of the natural ecosystems which served as the habitats for the indigenous species. Sparse vegetation and bare soil/farmlands increased over the study period and were seen as the major indices for modifications and forest loss in the area. Since land use indices such as agricultural activities were seen as one of the major factors of land cover change, sustainable forest use and management practices that accommodate agricultural practices were advocated. While the forest cover and ultimately their biodiversity and conservation prospects reduced following forest loss in the region, efforts should be targeted at conserving the pockets of vegetation seen in the sparsely vegetated zones and also maximize the potentials that the biodiversity in the agro-forested locations offers. 展开更多
关键词 biodiversity Carbon CLIMATE change FOREST Loss land use change Modification
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Disturbance impacts of land use change on biodiversity conservation priority areas across China: 1990-2010 被引量:28
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作者 ZHAO Guosong LIU Jiyuan +2 位作者 KUANG Wenhui OUYANG Zhiyun XIE Zhenglei 《Journal of Geographical Sciences》 SCIE CSCD 2015年第5期515-529,共15页
Land use change is one of the main drivers of biodiversity loss. In the last 20 years, China's land use pattern has undergone profound changes. This study constructs an Eco- system Comprehensive Anthropogenic Disturb... Land use change is one of the main drivers of biodiversity loss. In the last 20 years, China's land use pattern has undergone profound changes. This study constructs an Eco- system Comprehensive Anthropogenic Disturbance Index (ECADI) to assess disturbance impacts of land use change between 1990 and 2010 on biodiversity conservation priority areas at national and regional scales. Four levels of biodiversity conservation areas were categorized: generally important areas, moderately important areas, important areas, and very important areas. The results indicated a higher ECADI value in 2010 in Central and Eastern China than in Western China, and the values of the moderately important, important and very important regions were lower than the average value of the whole country at all levels. Notably, in recent 20 years, the change extent of ECADI values in Central and Eastern China were much greater compared with that in Western China, and ECADI values in the moderately important, important and very important biodiversity conservation areas all showed increasing trends, with the increasing extent lower than that of whole China at all levels. Due to human activities such as urbanization in Eastern China and cropland reclama- tion in Northeast China and Xinjiang, ECADI values showed a medium increase trend (the change rate was about 1%-5% in 10 years), which indicated the need for more conservation efforts in those regions. However, ECADI values in the Loess Plateau presented a low decline trend (the change rate was about-1% to -0.1% in 10 years) after 2000 because of the ob- vious effectiveness of Green for Grain Project. Furthermore, the variation was negligible in the Tibetan Plateau. 展开更多
关键词 land use/land cover change farmland reclamation URBANIZATION biodiversity DISTURBANCE
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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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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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Land Use and Land Cover Dynamics in the Eseka Alluvial Gold Mining District, Centre Region, Cameroon
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作者 Shu Vejiline Lum-Ndob Fonge Beatrice Ambo +3 位作者 Ambe Godlove Neba Ateh Kevin Ijunghi Enerst Tata Cheo Emmanuel Suh 《Journal of Geographic Information System》 2024年第4期289-305,共17页
Local populations in Cameroon thrive on forest resources and the flow of ecosystem services they provide are pivotal in sustaining national economy, improving people’s lives, safeguarding biodiversity, and mitigating... Local populations in Cameroon thrive on forest resources and the flow of ecosystem services they provide are pivotal in sustaining national economy, improving people’s lives, safeguarding biodiversity, and mitigating the impacts of environmental changes. The exploitation of these resources invariably leads to deforestation and forest degradation. This study was designed to evaluate land use land cover change (LULCC) in the Eseka alluvial gold mining district with the aid of Landsat images. In the investigation of forest cover change, four Landsat satellite images for (1990, 2002, 2015 and 2022) were used. Ground-truthing also helped to identify the activities carried out by the local population and to determine agents, drivers and pressures of land use and land cover change. Four main land cover classes namely: forest, agricultural land, settlement/mining camps and water bodies were selected. Between 1990 and 2022, the proportion of forest decreased from 98% to 34% while those of agricultural land and settlement/mining camps increased from 2% to 60% and 0.54% to 6% respectively. Analysis showed ongoing deforestation with forest cover loss of ~98,263 ha in 32 years giving a cover change percentage of 63.94%. Kappa coefficient for the study period ranged from 0.92 to 0.99. Forest cover loss could be attributed to farming activities, wood extraction and alluvial gold mining activities. Economic motives notably the need to increase household income from a frequent demand for farm and wood products in neighbouring towns and the quest for gold were the main drivers of these activities. Hence, this study assesses the impact of human activities from the mining sector on the forest ecosystem in a bid to inform mitigation policies. 展开更多
关键词 land use and land Cover changes biodiversity Alluvial Gold Mining DRIVERS landsat Images Ground-Truthing MITIGATION
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An Agent-Based Assessment of Land Use and Ecosystem Changes in Traditional Agricultural Landscape of Portugal 被引量:2
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作者 Lilibeth A.Acosta Mark D.A.Rounsevell +3 位作者 Martha Bakker Ann Van Doorn Montserrat Gomez-Delgado Marc Delgado 《Intelligent Information Management》 2014年第2期55-80,共26页
This paper presents an assessment of land use changes and their impacts on the ecosystem in the Montado, a traditional agricultural landscape of Portugal in response to global environmental change. The assessment uses... This paper presents an assessment of land use changes and their impacts on the ecosystem in the Montado, a traditional agricultural landscape of Portugal in response to global environmental change. The assessment uses an agent-based model (ABM) of the adaptive decisions of farmers to simulate the influence on future land use patterns of socio-economic attributes such as social relationships and farmer reliance on subsidies and biophysical constraints. The application and development of the ABM are supported empirically using three categories of input data: 1) farmer types based on a cluster analysis of socio-economic attributes;2) agricultural suitability based on regression analysis of historical land use maps and biophysical attributes;and 3) future trends in the economic and climatic environments based on the A1fi scenario of the Intergovernmental Panel on Climate Change. Model sensitivity and uncertainty analyses are carried out prior to the scenario analysis in order to verify the absence of systematic errors in the model structure. The results of the scenario analysis show that the area of Montado declines significantly by 2050, but it remains the dominant land use in the case study area, indicating some resilience to change. An important policy challenge arising from this assessment is how to encourage next generation of innovative farmers to conserve this traditional landscape for social and ecological values. 展开更多
关键词 ABANDONMENT Agent-Based Model Cluster Analysis Ecosystem and biodiversity land use change Logistic Regression PORTUGAL Scenario Analysis Traditional Agricultural landscape
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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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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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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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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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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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A method for estimating vegetation change over time and space 被引量:3
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作者 Norbert Kruchi 《Journal of Geographical Sciences》 SCIE CSCD 2003年第4期447-454,共8页
Plant diversity is used as an indicator of the well-being of vegetation and ecological systems. Human activities and global change drive vegetation change in composition and competition of species through plant invasi... Plant diversity is used as an indicator of the well-being of vegetation and ecological systems. Human activities and global change drive vegetation change in composition and competition of species through plant invasions and replacement of existing species on a given scale. However, species diversity indices do not consider the effects of invasions on the diversity value and on the functions of ecosystems. On the other hand, the existing methods for diversity index can not be used directly for cross-scale evaluation of vegetation data. Therefore, we proposed a 3-dimensional model derived from the logistic equation for estimating vegetation change, using native and non-native plant diversity. The two variables, based on the current and the theoretical maximum diversity of native plants on a given scale, and the result of the model are relative values without units, and are therefore scale-independent. Hence, this method developed can be used directly for cross-scale evaluations of vegetation data, and indirectly for estimating ecosystem or environmental change. 展开更多
关键词 biodiversity biological invasions ecosystem health global change land use
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Species Distribution and Patterns in a Forest-savannah Ecotone: Environmental Change and Conservation Concerns
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作者 Nwabueze Ikenna Igu 《Journal of Botanical Research》 2023年第3期27-35,共9页
Understanding the dynamics and patterns of biodiversity in transition forests is vital in promoting conservation and addressing environmental change issues.This work focused on elucidating the diversity,structure,and ... Understanding the dynamics and patterns of biodiversity in transition forests is vital in promoting conservation and addressing environmental change issues.This work focused on elucidating the diversity,structure,and carbon potentials of a forest-savannah ecosystem.To achieve this,8 forest plots that measured 50 m×50 m each was set up in a forest-savannah landscape and used to identify and measure tree species≥10 cm diameter at breast height(DBH measured at 130 cm).Species importance value was used to summarize the biodiversity patterns and the aboveground carbon estimates were elicited with the allometric equation.43 species within 22 families were enumerated and the diversity was generally low(ranging from 1.82-2.5).Species such as Daniellia oliveri(Rolfe)Hutch.&Dalziel,Py-rostria guinnensis Comm.ex A.Juss,Dialium guineense Willd.and Margariteria discoidea(Baill.)G.L Webster were the dominant species,and had the highest importance values of 113.06,55.13,28.16 and 16.95,respectively,while Allophlus africanus P.Beauv.,Annona senegalensis Pers.,Anthonatha macrophylla P.Beauv.,Ficus capensis Thumb.and Lecaniodiscus cupanioides Planch had the least importance values of 0.16 each.Carbon estimates ranged from 16.43172-42.9298 t/Ha.Most frequent species with higher basal areas no doubt contributed much to the carbon esti-mates,but did not have higher capacities in storing carbon.Managing the ecosystem with more carbon-dense species was seen as a suitable strategy for addressing environmental change in the ecosystem and region. 展开更多
关键词 biodiversity Carbon potentials Climate change Ecosystem conservation land use change
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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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气候变化和土地利用变化驱动下的生物多样性系统分析新框架 被引量:3
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作者 杨青 刘耕源 杨志峰 《生态学报》 CAS CSCD 北大核心 2024年第3期871-884,共14页
尽管目前已有大量关于生物多样性评估的研究,但同时考虑生物多样性多维评估、多驱动因素对生物多样性变化的影响评估及生物多样性变化中长期动态模拟预测等研究仍相对缺乏,这会引起对生物多样性不同维度变化水平的片面理解,导致生物多... 尽管目前已有大量关于生物多样性评估的研究,但同时考虑生物多样性多维评估、多驱动因素对生物多样性变化的影响评估及生物多样性变化中长期动态模拟预测等研究仍相对缺乏,这会引起对生物多样性不同维度变化水平的片面理解,导致生物多样性保护工程管理决策失误。基于此,综述现有生物多样性评估维度、驱动因素及历史评估的研究进展,并基于现有研究存在的局限性提出生物多样性多维评估方法与人地耦合系统下生物多样性模拟模型构建思路,基于此提出气候变化和土地利用变化驱动下的生物多样性系统分析新框架。该框架包括:①生物多样性“潜力-贡献-重要性”多维评估理论与方法构建;②人地耦合系统下生物多样性模拟模型构建;③人地耦合系统下生物多样性预测及生物多样性保护工程效果仿真与管理。该框架可为生物多样性保护工程管理及可持续开展提供科学建议。 展开更多
关键词 生物多样性保护 气候变化 土地利用变化 生态工程效果仿真 驱动机制 工程管理与调控
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Mapping and Floristic Diversity of the Nakpadjouak Community Forest, Tami Canton, Togo (West Africa)
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作者 Senyo Kossi Ehlui Christian Anthony-Krueger +4 位作者 Edinam Kola Wouyo Atakpama Alagie Bah Henrik von Wehrden Tchaa Boukpessi 《Natural Resources》 2024年第4期83-105,共23页
Since 2015, community forests have been promoted in Togo as an alternative to protect areas from degradation and as a means of contributing to forest landscape restoration. The study focuses on the Nakpadjouak Communi... Since 2015, community forests have been promoted in Togo as an alternative to protect areas from degradation and as a means of contributing to forest landscape restoration. The study focuses on the Nakpadjouak Community Forest (NCF) in Tami (Togo, West Africa) which contributes to community forests sustainable management. It aims in (i) mapping forest ecosystems and analysing their dynamic and (ii) characterizing the floristic diversity of the NCF. The ecosystems were mapped and their dynamic was evaluated based on Google Earth images of 2014 and 2020. Floristic and forestry inventories were carried out using the transect technique in a sample of 20 plots of 50 m × 20 m. The NCF was made up mainly by wooded/shrub savannahs (95.37%) and croplands/fallow (4.63%) in 2014. These two land use types undergone changes over the 6 years prior to 2020. By 2020, the NCF had 3 land use types: wooded/shrub savannahs (77.59%), open forest/wooded savannahs (22.23%), and croplands/fallows (0.18%). A total of 89 plant species belonging to 70 genera and 28 families were recorded within the NCF. The dominant species are: Heteropogon contortus (L.) P.Beauv. and Combretum collinum Fresen. followed by Pteleopsissuberosa Engl. & Diels, Annona senegalensis Pers. The most common species are: Lannea acida A.Rich. s.l., A. senegalensis, Vitellaria paradoxa C.F.Gaertner subsp. paradoxa, C. collinum and Acacia dudgeonii Craib ex Holland. Due to its small area of just 40 hectares and its diverse plant life, this community forest of Savannahs Region is a significant biodiversity hotspot and warrants conservation efforts. 展开更多
关键词 Community Forest Floristic Diversity land use change biodiversity Hotspot Tami Savannah Region TOGO
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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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