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An agent-based model of agricultural land expansion in the mountain forest of Timor Island,Indonesia
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作者 PUJIONO Eko SADONO Ronggo +12 位作者 IMRON Muhammad Ali SUTOMO JANUAR Hedi Indra KUSWANDI Relawan KURNIAWAN Hery HADI Etik Erna Wati SAPUTRA Muhammad Hadi HIDAYAH Izhamil HUMAIDA Nida SUKMAWATI Jalma Giring HADIYAN Yayan NUGROHO Agung Wahyu HANI Aditya 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2263-2282,共20页
The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns ... The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns indicate that deforestation primarily occurs at lower elevations and near the boundaries of forests and settlements,often associated with shifting cultivation by local farmers.This study adopts a process-based modelling approach,specifically the agent-based model,to simulate land changes,particularly farmers'expansion of agricultural land around the Mutis mountain forest.The underlying concept of this agent-based approach is the interaction between the human and environmental systems.Farmers,representing the human system,interact with the land,which represents the environmental system,through land use decision-making mechanisms.The research was conducted in the Community Forest of the Timor Tengah Utara District,one of the sites within the Mutis-Timau Forest Complex with the highest deforestation rate.Land use change simulations were performed using agent-based modelling from 1999 to 2030,considering the socio-economic conditions of farmers,spatial preferences,land use decisions,and natural transitions.The results revealed that the agricultural area increased by 14%under the Business as Usual scenario and 5%under the Reducing Emission from Deforestation and Forest Degradation scenario,compared to the initial agricultural area of 245 hectares.The probability of farmers deciding to extend agricultural activities was positively associated with the number of livestock maintained by farmers and the size of the village area.Conversely,the likelihood of farmers opting for agricultural extensification decreased with an increase in the area of private land and the farmer's age.These findings are crucial for the managers of the Mutis-Timau Forest Complex and other relevant stakeholders,as they aid in arranging actions to combat deforestation,designing proper forest-related policies,and providing support for initiatives such as reducing emissions from deforestation and forest degradation programs or further incentive schemes. 展开更多
关键词 Agricultural land expansion Simulation Agent-based model FARMER DEforestATION Mountainous tropical forest
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Anthropogenic Threats to Degraded Forest Land in the Savannahs’ Region of Togo from 1984 to 2020, West Africa
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作者 Kossi Senyo Ehlui Wouyo Atakpama +6 位作者 Henrik von Wehrden Alagie Bah Edinam Kola Christian Anthony-Krueger Hodabalo Egbelou Kokouvi Bruno Kokou Tchaa Boukpessi 《Journal of Geoscience and Environment Protection》 2024年第1期164-179,共16页
This study focuses on the landscape dynamics of the savannahs’ region in the far north of Togo. Based on a literature review and satellite images analysis using GIS and remote sensing, the study aims to ascertain the... This study focuses on the landscape dynamics of the savannahs’ region in the far north of Togo. Based on a literature review and satellite images analysis using GIS and remote sensing, the study aims to ascertain the effects of anthropogenic threats on the forest coverage of the Savannahs’ Region between 1984 to 2020. The objective is to clarify the dynamics of land use in the region from 1984 to 2000 and from 2000 to 2020. The findings indicate a significant decline in forest coverage within the region from 1984 to 2020, a trend attributed to land use patterns. Dry forests in the Savannah region are largely converted to farmlands, housing, dry savannahs or agroforestry parks, leading to a steady reduction in forest areas. 展开更多
关键词 forest Degradation land Use land Cover Savannahs Region TOGO
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Social and Environmental Impacts of Maryland Oil Palm Plantations on Forests,Biodiversity,and Community Livelihoods in Liberia
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作者 Richard N.Sam Sampson Williams +1 位作者 Nornor N.Bee Dioh Flahn 《Journal of Agricultural Science and Technology(A)》 2024年第2期83-92,共10页
Liberia holds 44.5% of the remaining portion of the Upper Guinean Rainforest in West Africa,which is home to critically endangered forest elephants and western chimpanzees.The forests are of vital importance for the l... Liberia holds 44.5% of the remaining portion of the Upper Guinean Rainforest in West Africa,which is home to critically endangered forest elephants and western chimpanzees.The forests are of vital importance for the livelihoods of millions of West Africans and provide key ecosystem services of local and global importance for food systems transformation and agroecology.Liberia’s efforts toward land reform through legislation and policies recognise communities’rights to own and manage their customary lands and resources.These include the National Forestry Reform Law of 2006,the Community Rights Law Concerning Forest Lands of 2009,and the Land Rights Act of 2018,and more.In May 2022,a program team from the Sustainable Development Institute(SDI)-Friends of the Earth Liberia researched the social and environmental impacts of Maryland Oil Palm Plantations(MOPPs)in Liberia.Twenty-three(23)key informant interviews(KIIs)and 10 focus group discussions(FGDs)were conducted in seven communities in and around the MOPP.They included farmers,contract workers,MOPP staff,local authorities,women and youth leaders,the Environmental Protection Agency(EPA)Inspector,the Civil Society Head,and the Gender Coordinator of Maryland County.The team cross-checked information with formal documents as much as possible and took photographs and global positioning system(GPS)locations of areas of deforestation,pollution,and conflict.The team also used observation to monitor environmental pollution,such as affluent into water bodies and planting oil palm in wetlands.The team used narrative analysis and geospatial landscape analysis to analyze the data.The research finds that land conflict and deforestation have several negative impacts on communities.MOPP has not respected land tenure rights or followed Free Prior and Informed Consent(FPIC)standards,including resettlement without reparation and destruction of farms and old towns without(sufficient)compensation or restitution.During MOPP land acquisition and clearance,communities experienced the loss of their farms and the identification of villages as“village de squatters”,leading to restricted access to farmland,heightened food insecurity,and reduced income from cash crops to support families.MOPP destroyed high conservation value areas and destroyed secondary forest regrowth,which affected important biodiversity areas.MOPP is one of the four large-scale industrial palm oil plantations in Liberia in Maryland County.It has a palm oil mill in a joint venture with Golden Veroleum Liberia(GVL).Its 2011 concession agreement includes 8,800 hectares for industrial palm oil plantations. 展开更多
关键词 BIODIVERSITY climate change community rights DEforestATION ecosystem services food security human rights land rights forest rights LIVELIHOOD
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Land Use and Forest Dynamics in the Context of Redd+: Pathway to Sustainable Environmental Management*
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作者 Princewill Odum 《Open Journal of Forestry》 2024年第1期117-126,共10页
Reverting to nature as a major arsenals in a universal fight against Climate Change impact and loss of biodiversity, the United Nations Convention to Combat Desertification (UNCCD), views sustainable Land use and Fore... Reverting to nature as a major arsenals in a universal fight against Climate Change impact and loss of biodiversity, the United Nations Convention to Combat Desertification (UNCCD), views sustainable Land use and Forest (the main crux of the Glasgow declaration 2021) as the way to go. Forest conservation, protection and management in the context of REDD+ would guarantee sustainable ecosystem and mitigate climate change impacts. At National and subnational levels, the Nigerian REDD+ readiness scheme holds out hope for environmental sustainability. This study throws light into the historical background of trends in land use forest change in Nigeria, and places Nigeria on a “red” stage 3 (Low Forest Cover, High Deforestation Rate-LFHD) status while maintaining optimism that with REDD+ properly implemented in Nigeria, Stage 4: Low forest cover, Low Deforestation Rates (LFLD) and Stage 5: Low forest cover, Negative Deforestation Rates (LFND) can be achieved by 2030 and 2050 respectively, if the trio of reforestation, afforestation and natural restoration is practiced as a matter of national policy and subnational implementation within the context of REDD+. Four (4) broad drivers of deforestation and forest degradation were identified as direct, indirect, pre-disposing and planned /unplanned. The paper concludes that a viable pathway to sustainable environmental management is appropriate monitoring and evaluation of land use and forest dynamics in the context of REDD+. 展开更多
关键词 land Use forest REDD+ SUSTAINABLE ENVIRONMENT Management
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Monitoring Study of Long-Term Land Subsidence during Subway Operation in High-Density Urban Areas Based on DInSAR-GPS-GIS Technology and Numerical Simulation
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作者 Yu Song Xuejun Chen +4 位作者 Baoping Zou Jundong Mu Rusheng Hu Siqi Cheng Shengli Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1021-1039,共19页
During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil d... During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation. 展开更多
关键词 Long-term land subsidence subway operation DInSAR-GPS-GIS technology high-density urban areas urban subway numerical simulation
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Strategies for Safe Land Use of the Three Gorges Reservoir Area (Chongqing Section)——With the Restoration of Degraded Forest Landscapes as a Study Case
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作者 牟萍 《Journal of Landscape Research》 2010年第8期51-55,共5页
As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe op... As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe operation of the Three Gorges, and meet requirements of integrated development strategies for ecological and economic effects in Chongqing City on the ecological security of land use in Chongqing section of the Three Gorges, the following points should be attached more importance in making future strategies for an ecologically safe land use pattern with the restoration of degraded forest landscape as its starting point:a. Ecological effects and economic functions that can be supplied by forest landscape elements in different restoration patterns should be understood to obtain background effect of the ecological security pattern scenario of land use in the reservoir region; b. Relationship between restoration of degraded forest landscapes and serious ecological interference factors such as degradation background, artificial disturbance and engineering stress, should be simulated to figure out the influence of natural or artificial driving factors on landscape pattern, determine the future restoration mode for the degraded forest landscapes in the reservoir region, so as to facilitate the construction of great ecological-economic security pattern of the Three Gorges. The findings will provide scientific basis for the decision-making in building an ecologically safe land use pattern in the Three Gorges reservoir area (Chongqing), when using the degradation of forest landscape restoration as a carrier at present or in the future. Further, they will help realize the development goals of "Livable Chongqing, Expedite Chongqing, Forestry Chongqing, Safe Chongqing and Healthy Chongqing". 展开更多
关键词 land use Ecological-economic security forest landSCAPE The Three Gorges reservoir region
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Quantitative Simulation of Dynamic Changes in Cultivated Land in Areas of Reclamation and Returning Cultivated Land to Forest or Pastures under RCPs Climate Scenarios 被引量:1
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作者 刘唯清 齐元静 +1 位作者 姜群鸥 聂承静 《Agricultural Science & Technology》 CAS 2016年第1期178-187,共10页
Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the... Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system(DLS) model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways(RCPs) scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model(AIM)scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact(MESSAGE) scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change. 展开更多
关键词 land use Climate change Planning Cultivated land change Quantitative simulation Scenario Areas of reclamation and returning cultivated land to forest or pastures
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Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management 被引量:4
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作者 Rafael M~a Navarro Cerrillo Dennis J.Esteves Vieira +2 位作者 Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar Delgado Serrano 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期143-155,共13页
Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat im... Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control. 展开更多
关键词 Tropical and TEMPERATE forestS Social forestRY land uses segmentation OBIA FRAGSTAT
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Integrated use of GIS, remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry 被引量:5
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作者 Naser Ahmadi Sani Sasan Babaie Kafaky +1 位作者 Timo Pukkala Asadollah Mataji 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期1127-1135,共9页
The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems (GIS) and multi-criteria decision analysis (MCDA) have been inc... The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems (GIS) and multi-criteria decision analysis (MCDA) have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing (RS) to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, G1S and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses. 展开更多
关键词 Analytic hierarchy process Decisionanalysis Ecological suitability land allocation land-use planning - Spatial analysis - Zagros forests
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:20
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values o... Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 展开更多
关键词 Pinus sylvestris var. mongolica Mongolian pine Sandy land Natural regeneration Canopy openness forest gap Regeneration index
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Comparison of foliar nutrient concentrations between natural and artificial forests of Pinus sylvestris var. mongolica on sandy land, China 被引量:7
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作者 ZHU Jiao-jun TAN Hui +1 位作者 KANG Hong-zhang XU Mei-ling 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期177-184,共8页
In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris v... In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris var. mongolica trees from two provenances (natural forests and plantations). The results indicated that natural tree needles had lower N, P and C concentrations, and higher K concentrations than those of plantation tree needles. For plantation tree needles, ratios of N: P, P. K and N: K increased with tree age before 45 years old; but they were not clear for the natural tree needles. Compared with the conclusions reported on Pinus spp., we found that the foliar N and P concentrations were in the optimal range for both natural and plantation tree needles. This result suggested that N or P might not be the absolute limit factors in plant nutrient for P sylvestris var. mongolica on sandy land. However, foliar K concentrations in both natural and plantation tree needles were much lower than those reported on Pinus spp. (〉4.80 g kg-1).The N: P ratio of natural needles was in the adequate ranges, but N: P ratio of plantation needles was out of the adequate ranges. These results indicated that there was a better balanced nutrition status in the natural forest than in the plantations. If only considering the foliar nutrient concentrations of P sylvestris var. mongolica from different provenances, it might be concluded that the degradation phenomenon of P. sylvestris var. mongolica plantations was not induced by nutrition deficiency of absolute nutrients of N and P, but might be induced by other mineral nutrients or by the effectiveness of N and P nutrients. The unbalanced nutrition status and relatively quick decomposition of needles in the plantations might also contribute to the degradation. 展开更多
关键词 Degradation phenomenon forest ecosystem on sandy land N: P ratio Natural Mongolian pine Pinus sylvestris var. mongolica Plantation Mongolian pine
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Impact of land-use management on nitrogen transformation in a mountain forest ecosystem in the north of Iran 被引量:3
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作者 Maryam Asadiyan Seyed Mohammad Hojjati +1 位作者 Mohammad reza Pourmajidian Asghar fallah 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期115-119,共5页
Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in... Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in soil N dynamics. This study was conducted to determine the soil inorganic N concentrations and net N mineralization rate in four common types of land-uses in the mountain forest area in the north of Iran, namely arable land, pine plantation, ash plantation, and beech stand. The soil samples were taken from top mineral soil layer (5 cm) in each site randomly (n=6) during August- September 2010. Beech stand and ash plantation showed significantly higher total nitrogen compared with arable land and pine plantation, while extractable NH4 +-N concentration was significantly greater in Beech stand compare to arable soils (p〈0.05). No significantly difference was found in Net N mineralization, net nitrification and net ammonification rates among different land-uses. Results showed that net N mineralization and ammonification were occurred just in the soil of Ash plantation during the incubation time. Our findings suggested that conversion of Hyrcanian forests areas to pine plantation and agricultural land can disrupt soil natural activities and affect extremely soil quality. 展开更多
关键词 soil quality net N mineralization nitrogen dynamic land use Hyrcanian forest Alandan.
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Comparison and Analysis of Agricultural and Forest Land Changes in Typical Agricultural Regions of Northern Mid-latitudes 被引量:3
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作者 LIU Tingxiang ZHANG Shuwen +1 位作者 TANG Junmei LI Tianqi 《Chinese Geographical Science》 SCIE CSCD 2013年第2期163-172,共10页
The northeastern China, the United States, and the western Europe are important agricultural regions both on the global and regional scales. The westem Europe has a longer history of agricultural land development than... The northeastern China, the United States, and the western Europe are important agricultural regions both on the global and regional scales. The westem Europe has a longer history of agricultural land development than the eastem United States. These two regions have changed from the deforestation and reclamation phase in the past to the current land abandonment and reforestation phase. Compared with the two regions, large-scale land exploitation has only been practiced in the northeastern China during the last century. After a short high-intensity deforestation and reclamation period, agricultural and forest lands are basically in a dynamic steady state. By comparing domestic and international agro-forestry development and considering the ecological environment and socio-economic bene- fits that can be derived from agro-forestry, this paper suggests that large area of reforestation would be inevitable in future though per- sistent and large agricultural demand in coming decades even more. And local reforestation at slope farmland with ecological vulner- ability should be imperative at present to avoid severer damage. At the same time, from the perspective of Land Change Science, the results demonstrate that the research on land use change in the agro-forestry ecotone is typical and critical, particularly those dealing with the analysis of spatial and temporal characteristics and the simulation of climate, hydrology, and other environmental effects. 展开更多
关键词 agricultural land change forest land change REforestATION agro-forestry ecotone northeastern China Europe United States
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Impacts of anthropogenic and biophysical factors on ecological land using logistic regression and random forest:A case study in Mentougou District,Beijing,China 被引量:3
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作者 TIAN Chao CHENG Lin-lin YIN Ting-ting 《Journal of Mountain Science》 SCIE CSCD 2022年第2期433-445,共13页
Ecological land is an important guarantee to maintain urban ecological security and sustainable development.Although increasing studies have been brought to ecological land,with few explorations of the relative import... Ecological land is an important guarantee to maintain urban ecological security and sustainable development.Although increasing studies have been brought to ecological land,with few explorations of the relative importance of anthropogenic-natural factors and how they interact to induce the ecological land evolution.This research sought to fill this gap.In this study,18 factors,including the risk of goaf collapse,fault,prime croplands,were selected from six aspects of topography,geology,climate,accessibility,socio-economic and land control policies.logistic regression(LR)and random forest(RF)models were adopted to identify the anthropogenic and biophysical factors on the dynamic change of ecological land of Mentougou in Beijing from 1990 to 2018.The results show that there was a significant increase in ecological land from 1990 to 2018.The increased area of ecological land reached 102.11 km2 with an increased rate of 0.78,the gravity center of ecological land gradually moved to the northwest.The impact of anthropogenic factors on ecological land was greater than that of natural factors,ecological land was mainly driven by proportion of prime cropland,per capita GDP,land urbanization,temperature,per capita rural income,elevation and aspect factors.Additionally,slope and precipitation were also identified as important predictors for ecological land change.The model comparison suggested that RF can better identify the relationship between ecological land and explanatory variables than LR model.Based on our findings,the implementation of government policies along with anthropogenic factors are the most important variables influencing ecological land change,and the rational planning and allocation of ecological land by Mentougou government are still needed. 展开更多
关键词 Logistic regression Random forest Ecological land Determinants Dynamic change
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Rapid Urbanization Induced Extensive Forest Loss to Urban Land in the Guangdong-Hong Kong-Macao Greater Bay Area, China 被引量:4
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作者 YANG Chao LIU Huizeng +7 位作者 LI Qingquan CUI Aihong XIA Rongling SHI Tiezhu ZHANG Jie GAO Wenxiu ZHOU Xiang WU Guofeng 《Chinese Geographical Science》 SCIE CSCD 2021年第1期93-108,共16页
China has experienced rapid urbanizations with dramatic land cover changes since 1978. Forest loss is one of land cover changes, and it induces various eco-environmental degradation issues. As one of China’s hotspot ... China has experienced rapid urbanizations with dramatic land cover changes since 1978. Forest loss is one of land cover changes, and it induces various eco-environmental degradation issues. As one of China’s hotspot regions, the Guangdong-Hong KongMacao Greater Bay Area(GBA) has undergone a dramatic urban expansion. To better understand forest dynamics and protect forest ecosystem, revealing the processes, patterns and underlying drivers of forest loss is essential. This study focused on the spatiotemporal evolution and potential driving factors of forest loss in the GBA at regional and city level. The Landsat time-series images from 1987 to2017 were used to derive forest, and landscape metrics and geographic information system(GIS) were applied to implement further spatial analysis. The results showed that: 1) 14.86% of the total urban growth area of the GBA was obtained from the forest loss in1987–2017;meanwhile, the forest loss area of the GBA reached 4040.6 km2, of which 25.60%(1034.42 km2) was converted to urban land;2) the percentages of forest loss to urban land in Dongguan(19.14%), Guangzhou(18.35%) and Shenzhen(15.81%) were higher than those in other cities;3) the forest became increasingly fragmented from 1987–2007, and then the fragmentation decreased from2007 to 2017);4) the landscape responses to forest changes varied with the scale;and 5) some forest loss to urban regions moved from low-elevation and gentle-slope terrains to higher-elevation and steep-slope terrains over time, especially in Shenzhen and Hong Kong.Urbanization and industrialization greatly drove forest loss and fragmentation, and, notably, hillside urban land expansion may have contributed to hillside forest loss. The findings will help policy makers in maintaining the stability of forest ecosystems, and provide some new insights into forest management and conservation. 展开更多
关键词 forest loss to urban land urbanization spatiotemporal pattern remote sensing Guangdong-Hong Kong-Macao Greater Bay Area(GBA)
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Land use change detection in Solan Forest Division,Himachal Pradesh,India 被引量:1
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作者 Shipra Shah DP Sharma 《Forest Ecosystems》 SCIE CSCD 2015年第4期327-338,共12页
Background: Monitoring the changing pattern of vegetation across diverse landscapes through remote sensing is instrumental in understanding the interactions of human activities and the ecological environment. Land us... Background: Monitoring the changing pattern of vegetation across diverse landscapes through remote sensing is instrumental in understanding the interactions of human activities and the ecological environment. Land use pattern i the state of Himachal Pradesh in the Indian Western Himalayas has been undergoing rapid modifications due to changing cropping patterns, rising anthropogenic pressure on forests and government policies. We studied land use change in Solan Forest Division of Himachal Pradesh to assess species wise area changes in the forests of the region. Methods: The supervised classification (Maximum likelihood) on two dates of IRS (LISS III) satellite data was performed to assess land use change over the period 1998-2010. Results: Seven land use categories were identified namely, chir pine (Pinus roxburghii) forest, broadleaved forest, bamboo (Dendrocolamus strictus) forest, ban oak (Quercus leucotrichophora) forest, khair (Acacia catechu) forest, culturable blank and cultivation. The area under chir pine, cultivation and khair forests increased by 191 ha (4.55 %), 129 ha (13.81%) and 77 ha (23.40 %), whereas the area under ban oak, broadleaved, culturable blank and bamboo decreased by 181 ha (16.58 %), 152 ha (6.30 %), 71 ha (2.72 %) and 7 ha (0.47 %), respectively. Conclusions: The study revealed a decrease in the area under forest and culturable blank categories and a simultaneous increase in the area under cultivation primarily due to the large scale introduction of horticultural cash crops in the state. The composition of forests also exhibited some major changes, with an increase in the area of commercially important monoculture plantation species such as pine and khair, and a decline in the area of oak, broadleaved and bamboo which are facing a high anthropogenic pressure in meeting the livelihood demands of forest dependent communities. In time deforestation, forest degradation and ecological imbalances due to the changing forest species composition may inflict irreversible damages upon unstable and fragile mountain zones such as the Indian Himalayas. The associated common property externalities involved at local, regional and global scales, necessitate the monitoring of land use dynamics across forested landscapes in developing future strategies and policies concerning agricultural diversification, natural forest conservation and monoculture tree plantations. 展开更多
关键词 land use Solan forest Division Supervised Classification Maximum likelihood
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Characterisation of Landscape with ForestFragmentation Dynamics 被引量:2
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作者 T. V. Ramachandra Uttam Kumar 《Journal of Geographic Information System》 2011年第3期242-253,共12页
Land cover (LC) and land use (LU) dynamics induced by human and natural processes play a major role in global as well as regional patterns of landscapes influencing biodiversity, hydrology, ecology and climate. Change... Land cover (LC) and land use (LU) dynamics induced by human and natural processes play a major role in global as well as regional patterns of landscapes influencing biodiversity, hydrology, ecology and climate. Changes in LC features resulting in forest fragmentations have posed direct threats to biodiversity, endangering the sustainability of ecological goods and services. Habitat fragmentation is of added concern as the residual spatial patterns mitigate or exacerbate edge effects. LU dynamics are obtained by classifying temporal remotely sensed satellite imagery of different spatial and spectral resolutions. This paper reviews five different image classification algorithms using spatio-temporal data of a temperate watershed in Himachal Pradesh, India. Gaussian Maximum Likelihood classifier was found to be apt for analysing spatial pattern at regional scale based on accuracy assessment through error matrix and ROC (receiver operating characteristic) curves. The LU information thus derived was then used to assess spatial changes from temporal data using principal component analysis and correspondence analysis based image differencing. The forest area dynamics was further studied by analysing the different types of fragmentation through forest fragmentation models. The computed forest fragmentation and landscape metrics show a decline of interior intact forests with a substantial increase in patch forest during 1972-2007. 展开更多
关键词 land COVER Algorithms ROC Curve Spatial Change CORRESPONDENCE Analysis forest FRAGMENTATION
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Google Earth Engine Based Three Decadal Landsat Imagery Analysis for Mapping of Mangrove Forests and Its Surroundings in the Trat Province of Thailand 被引量:1
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作者 Uday Pimple Dario Simonetti +6 位作者 Asamaporn Sitthi Sukan Pungkul Kumron Leadprathom Henry Skupek Jaturong Som-ard Valery Gond Sirintornthep Towprayoon 《Journal of Computer and Communications》 2018年第1期247-264,共18页
Monitoring and understanding the changes in mangrove ecosystems and their surroundings are required to determine how mangrove ecosystems are constantly changing while influenced by anthropogenic, and natural drivers. ... Monitoring and understanding the changes in mangrove ecosystems and their surroundings are required to determine how mangrove ecosystems are constantly changing while influenced by anthropogenic, and natural drivers. Cosistency in high spatial resolution (30 m) satellite and high performance computing facilities are limiting factors to the process, with storage and analysis requirements. With this, we present the Google Earth Engine (GEE) based approach for long term mapping of mangrove forests and their surroundings. In this study, we used a GEE based approach: 1) to create atmospheric contamination free data from 1987-2017 from different Landsat satellite imagery;and 2) evaluating the random forest classifier and post classification change detection method. The obtained overall accuracy for the years 1987 and 2017 was determined to be 0.87 and 0.96, followed by a Kappa coefficient 0.80 and 0.94. The change detection results revealed a significant decrease in the agricultural area, while there was an increase in mangrove forest, shrimp/fish farm, and bareland area. The results suggest that interconversion of land use and land cover is affecting the landscape dynamics within the study area. 展开更多
关键词 Google Earth ENGINE landsat Random forest MANGROVE forest land Use land Cover Change
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Characterizing changes in land cover and forest fragmentation from multitemporal Landsat observations(1993-2018)in the Dhorpatan Hunting Reserve,Nepal 被引量:1
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作者 Yali Zhang Sandeep Sharma +1 位作者 Manjit Bista Mingshi Li 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期159-170,共12页
Natural forces and anthropogenic activities greatly alter land cover,deteriorate or alleviate forest fragmentation and affect biodiversity.Thus land cover and forest fragmentation dynamics have become a focus of conce... Natural forces and anthropogenic activities greatly alter land cover,deteriorate or alleviate forest fragmentation and affect biodiversity.Thus land cover and forest fragmentation dynamics have become a focus of concern for natural resource management agencies and biodiversity conservation communities.However,there are few land cover datasets and forest fragmentation information available for the Dhorpatan Hunting Reserve(DHR)of Nepal to develop targeted biodiversity conservation plans.In this study,these gaps were filled by characterizing land cover and forest fragmentation trends in the DHR.Using five Landsat images between 1993 and 2018,a support vector machine algorithm was applied to classify six land cover classes:forest,grasslands,barren lands,agricultural and built-up areas,water bodies,and snow and glaciers.Subsequently,two landscape process models and four landscape metrics were used to depict the forest fragmentation situations.Results showed that forest cover increased from 39.4%in 1993 to 39.8%in 2018.Conversely,grasslands decreased from 38.2%in 1993 to 36.9%in 2018.The forest shrinkage was responsible for forest loss during the period,suggesting that the loss of forest cover reduced the connectivity between forest and nonforested areas.Expansion was the dominant component of the forest restoration process,implying that it avoided the occurrence of isolated forests.The maximum value of edge density and perimeter area fractal dimension metrics and the minimum value of aggregation index were observed in 2011,revealing that forests in this year were most fragmented.These specific observations from the current analysis can help local authorities and local communities,who are highly dependent on forest resources,to better develop local forest management and biodiversity conservation plans. 展开更多
关键词 land cover forest fragmentation Spatial process model FRAGSTATS
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Land Use/Land Cover and Forest Canopy Density Monitoring of Wafi-Golpu Project Area, Papua New Guinea 被引量:2
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作者 Slady Akike Sailesh Samanta 《Journal of Geoscience and Environment Protection》 2016年第8期1-14,共14页
This study aims to examine the use of Remote Sensing and Geographical Information System (GIS) technology in land use/land cover mapping to aide sustainable planning and development in the Wafi-Golpu project area. At ... This study aims to examine the use of Remote Sensing and Geographical Information System (GIS) technology in land use/land cover mapping to aide sustainable planning and development in the Wafi-Golpu project area. At the same time, this study examines an existing method of Forest Canopy Density (FCD) model to estimate forest canopy density of the proposed deforestation site, which is known as the Advanced Exploration Feasibility Study Activities (AEFSA) area within the Wafi-Golpu Project site. The FCD model calculates the forest canopy density using the three (3) indices of vegetation, soil and shadow from the Landsat-8 Operational Land Imager (OLI) satellite image of year 2013. In this study an attempt has been made to monitor the forest loss or degradation during deforestation in a natural forest stand of the Wafi-Golpu project area using forest FCD mapping and monitoring model and the findings of the study will assist the project planners and developers with their work on forest rehabilitation and reforestation for the purposes of sustainable forest management. The result of the work shows that a considerable amount of forest loss will be undertaken during the AEFSA deforestation exercise and also the findings show that a reliable land use/land cover map will greatly assist sustainable development in a resource project development period. 展开更多
关键词 Remote Sensing GIS FCD Model land Use/land Cover forest land Management
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