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Exploring the Spatiotemporal Changes and Driving Forces of Ecosystem Services of Zhejiang Coasts,China,Under Sustainable Development Goals
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作者 ZHANG Shu SUN Chao +2 位作者 ZHANG Yixin HU Ming SHEN Xingru 《Chinese Geographical Science》 SCIE CSCD 2024年第4期647-661,共15页
Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human beings.Over recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resul... Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human beings.Over recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resulting in biodiversity and habitat loss,environmental pollution,and the depletion of natural resources.In response to these environmental challenges,the Sustainable Development Goals(SDGs)were proposed.Given the pressing need to address these issues,understanding the changes in ESs under the SDGs is crucial for formulating specific ecological strategies.In this study,we first analyzed land use and cover change in the Zhejiang coasts of China during 2000–2020.Then,we investigated the spatiotemporal configuration of ESs by integrating carbon storage(CS),soil retention(SR),habitat quality(HQ)and water yield(WY)using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.The driving mechanisms of ESs,which varied by space and time,were also explored using the Geo-detector method.The results revealed that,over the past two decades:1)the Zhejiang coasts have experienced a significant increase of 2783.72 km^(2) in built-up land areas and a continuous decrease in farmland areas due to rapid urbanization;2)owing to higher precipitation,extensive vegetation cover,and reduced anthropogenic disturbances,forests emerge as a crucial land use type for maintaining ecosystem services such as HQ,CS,WY,and SR;3)ESs have generally declined across the entire Zhejiang coasts,with a significant decrease observed in the northern areas and an increase in the southern areas spatially;4)the expansion of built-up land areas emerged as the primary factor affecting ecosystem services,while the vegetation factor has been increasingly significant and is expected to become predominant in the near future.Our study provides insights of understanding of ecosystem service theory and emphasizing the importance of preserving biodiversity for long-term sustainable development,and valuable scientific references to support the ecological management decision-making for local governments. 展开更多
关键词 ecosystem services(ESs) Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model Geo-detector land use and cover change(LUCC) Zhejiang coasts China
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Land Use Land Cover Analysis for Godavari Basin in Maharashtra Using Geographical Information System and Remote Sensing
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作者 Pallavi Saraf Dattatray G. Regulwar 《Journal of Geographic Information System》 2024年第1期21-31,共11页
The dynamic transformation of land use and land cover has emerged as a crucial aspect in the effective management of natural resources and the continual monitoring of environmental shifts. This study focused on the la... The dynamic transformation of land use and land cover has emerged as a crucial aspect in the effective management of natural resources and the continual monitoring of environmental shifts. This study focused on the land use and land cover (LULC) changes within the catchment area of the Godavari River, assessing the repercussions of land and water resource exploitation. Utilizing LANDSAT satellite images from 2009, 2014, and 2019, this research employed supervised classification through the Quantum Geographic Information System (QGIS) software’s SCP plugin. Maximum likelihood classification algorithm was used for the assessment of supervised land use classification. Seven distinct LULC classes—forest, irrigated cropland, agricultural land (fallow), barren land, shrub land, water, and urban land—are delineated for classification purposes. The study revealed substantial changes in the Godavari basin’s land use patterns over the ten-year period from 2009 to 2019. Spatial and temporal dynamics of land use/cover changes (2009-2019) were quantified using three Satellite/Landsat images, a supervised classification algorithm and the post classification change detection technique in GIS. The total study area of the Godavari basin in Maharashtra encompasses 5138175.48 hectares. Notably, the built-up area increased from 0.14% in 2009 to 1.94% in 2019. The proportion of irrigated cropland, which was 62.32% in 2009, declined to 41.52% in 2019. Shrub land witnessed a noteworthy increase from 0.05% to 2.05% over the last decade. The key findings underscored significant declines in barren land, agricultural land, and irrigated cropland, juxtaposed with an expansion in forest land, shrub land, and urban land. The classification methodology achieved an overall accuracy of 80%, with a Kappa Statistic of 71.9% for the satellite images. The overall classification accuracy along with the Kappa value for 2009, 2014 and 2019 supervised land use land cover classification was good enough to detect the changing scenarios of Godavari River basin under study. These findings provide valuable insights for discerning land utilization across various categories, facilitating the adoption of appropriate strategies for sustainable land use in the region. 展开更多
关键词 GIS Remote Sensing Land Use Land Cover Change Change Detection Supervised Classification
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How Land Use Policies Are Transforming Shifting Cultivation to Short Fallow Systems and Permanent Cultivation of Annual Crops in Tanzania
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作者 Charles Joseph Kilawe 《Open Journal of Forestry》 2024年第4期397-412,共16页
Recent studies show that shifting cultivation in Tanzania has transformed into more intensive farming practices. One of the drivers of this shift is the implementation of policies that favor sedentary farming. However... Recent studies show that shifting cultivation in Tanzania has transformed into more intensive farming practices. One of the drivers of this shift is the implementation of policies that favor sedentary farming. However, there is inadequate information on how this transformation operates at the village level. Based on a case study of one village in Central Tanzania, this study demonstrates that the village land use plan is the primary policy tool for the transformation and intensification of shifting cultivation at the village level. Through the land use planning process, land is allocated only for lawful uses such as settlement, permanent cultivation, and the village forest reserve. No land is designated for shifting cultivation. Additionally, the land use plans are accompanied by by-laws that restrict shifting cultivation practices, such as the use of fire during land preparation and leaving the land fallow for more than 3 years. The intensification of shifting cultivation was not associated with an increase in the use of farm inputs such as improved seeds, fertilizer, or irrigation, as is commonly practiced in sustainable intensive agriculture. Instead, it was associated with the adoption of short fallow farming systems and labor-intensive land preparation methods, such as deep plowing to loosen the soil and sub-soiling vegetation. 展开更多
关键词 Land Use Planning Land Use Change Short Fallow Systems SLASH-AND-BURN
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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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Assessment of the Variations in Soil Physicochemical Parameters of the Natural Forest and Plantations in Orumba North Local Government Area, Anambra State, Nigeria
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作者 Maureen Chinwe Odachi Nwabueze Ikenna Igu Ifeanyi Chris Onwuadiochi 《Journal of Geoscience and Environment Protection》 2024年第10期132-151,共20页
Soil physicochemical parameters are the physical and chemical characteristics of soil such as pH, bulk density, organic carbon, nitrogen content, and nutrient levels at different soil depths. These parameters vary fro... Soil physicochemical parameters are the physical and chemical characteristics of soil such as pH, bulk density, organic carbon, nitrogen content, and nutrient levels at different soil depths. These parameters vary from one vegetation to the other and from one soil to the other. The study assessed the variations in soil physicochemical parameters of the natural forest and plantations in Agu Eke (Eke bush) in Etti village, Nanka and Umunnebo village, Ufuma both located in Orumba North Local Government Area, Anambra State. The experimental research design and stratified random sampling methods were used for the study and a total of 12 soil samples were collected at 30 cm depth from the selected locations of natural forest, cashew and palm plantations. The samples were analyzed using laboratory Varian AA240 Atomic Absorption Spectrophotometer, after which the result was subjected to statistical analysis—Analysis of Variance (ANOVA). The study found that there was no significant difference (variation) between the moisture contents of natural forests and the plantations;that is, the moisture contents were the same. It was also found that there was no significant variation between the bulk densities of the natural forest, oil plantation, and cashew plantation, meaning that the bulk densities were significantly the same. However, there were significant variations in nitrogen, potassium and phosphates, with p-values: sig = .000 < .05, sig = .010 < .05 and sig = .000 < .05, respectively. That is, the nitrogen and phosphate contents of the natural forest significantly vary more than those of the oil palm and cashew plantations, which probably means that by reducing natural forest to plantation, the nitrogen and phosphate contents of the natural forest reduced from what it used to be when the lands were mere forests. This shows that plantations do not have the same function of maintaining or improving soil quality as natural forests. The study recommended adopting a sustainable plantation agricultural system, such as using diverse nutrient sources (manure and compost), in order to maintain the desired soil quality. 展开更多
关键词 ECOSYSTEM Land Use Change Soil Quality Physical and Chemical Characteristics
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Exploring the Forest Cover Changes and Influential Factors of Dongsithouane National Production Forest Area, Savannakhet Province, Lao PDR
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作者 Souvanthone Douangphachachanh Chittana Phompila +5 位作者 Dipjoy Chakma Inta Chanthavong Maliphone Douangphachanh Puvadol Doydee Pengxiang Zhao Yuanchun Yu 《Journal of Data Analysis and Information Processing》 2024年第3期432-461,共30页
The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant chang... The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant changes in land use and land cover (LULC) have been observed in this area, leading to a reduction of natural forests. There were two separate methods of this study: firstly, to identify LULC changes across three different periods, spectral imagery from the Landsat 5 Thematic Mapper (TM) for the years 2001 and 2011, and the Landsat 8 Operational Land Imager (OLI) for 2021 were used as the primary data sources. The satellite images were preprocessed for various forest classes, including pretreatment of the top of atmosphere reflectance by using QGIS software’s semi-automatic classification plug-in (SCP), and ArcGIS was used for post-classification. A supervised classification approach was applied to the satellite images from 2001, 2011, and 2021 to generate diverse maps of LULC. Secondly, a household survey dataset was used to investigate influential factors. Approximately 220 households were interviewed in order to collect socio-economic information (including data on population growth, increased business activities, location of the area, agriculture land expansion, and need for settlement land). Household survey data was analyzed by using SPSS. Descriptive statistics, including frequency distributions and percentages, were applied to observe characteristics. Additionally, a binary logistic regression model was used to analyze the socioeconomic factors related to LULC change in DNPF. Key findings indicated a decline in natural forest areas within the study site. Specifically, both dry dipterocarp forest (−11.35%) and mixed deciduous forest (−0.18%) decreased from 2001 to 2021. The overall accuracy of the LULC maps was 94%, 86%, and 89% for the years 2001, 2011, and 2021 respectively. In contrast, agricultural land increased significantly by 155.70%, while built-up land, and water bodies increased by 65.54% and 35.33%, respectively. The results also highlighted a significant increase in construction land, up to 65.54%. Furthermore, the study found a correlation between agricultural expansion and a reduction of forest areas, along with an increase in built-up land along the forest areas’ boundaries. Timber exploitation and charcoal production also contributed to the decline in forest cover. The logistic regression model identified significant determinants of LULC change, including the area’s location, agricultural land expansion, increased business activity, and the need for settlement land. These factors have influenced the management of DNPF. Urgent sustainable management practices and actions, including forest ecosystem protection, village agricultural zoning, water source and watershed protection and public awareness, are required to preserve the forest areas of DNPF. 展开更多
关键词 Land Use/Land Cover Change QGIS SCP Socioeconomic Factor Dongsithouane National Production forest Lao PDR
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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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Impact of slope farmland use change on ecosystem services value in China,2000-2020 被引量:1
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作者 ZENG Jie BIAN Jiao-jiao CHEN Wan-xu 《Journal of Mountain Science》 SCIE CSCD 2023年第3期821-833,共13页
Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecos... Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecosystem services(ESs)is critical for effective land utilization and ecosystem protection.This study aims to analyze slope farmland changes in China between 2000 and 2020 and quantify the impact of these changes on ESs by the use of a land use dynamic attitude study,and an ecosystem services value(ESV)equivalent.Results show that the area of slope farmland in China was mainly concentrated on slopes of 2°-6°,and exhibited a downward trend between 2000 and 2020.There were significant differences in the spatial distribution of the farmland,which was mainly located in the Taihang,Qinling,Wushan,and Xuefeng mountains.ESV increased by$179.235 million due to the conversion between slope farmland and forest,grassland,and construction land from 2000-2010.Conversely,from 2010 to 2020,ESV decreased by$2613.919 million due to the conversion of forest and grassland to slope farmland as well as the conversion of slope farmland to construction land. 展开更多
关键词 Slope farmland change Revised benefit transfermethod Ecosystemservicesvalue Ecosystem services management Slope farmland utilization China
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Study on Farmland Use Change and Driving Force in the High and Cold Areas in Northwest Yunnan——A Case Study of Ninglang Yi Autonomous County
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作者 LUO Li1,YANG Zi-sheng1,KANG Yun-hai1,21.Land Resources and Sustainable Development Institute,Yunnan University of Finance and Economics,Kunming 650221,China 2.Yunnan Academy of Social Sciences,Kunming 650034,China 《Asian Agricultural Research》 2011年第3期79-82,共4页
On the basis of overview of the study area,by analyzing the dynamic change of farmland in Ninglang County,we can find that the farmland area in this county tended to decrease from 1996 to 2008.According to the investi... On the basis of overview of the study area,by analyzing the dynamic change of farmland in Ninglang County,we can find that the farmland area in this county tended to decrease from 1996 to 2008.According to the investigation data concerning land change provided by Bureau of Land and Resources in Ninglang County and socio-economic data provided by Bureau of Statistics in Ninglang County,we select 11 indices,such as total population,GDP,total output value of county and so on,coupled with SPSS statistical method,we adopt principal component analysis method to analyze driving force factors of farmland use change in the high and cold areas in Northwest Yunnan.The results show that the two factors of economic development and population growth are the dominant driving factors impacting farmland use change,and the policy factors,such as "returning farmland to forests",are also the important driving factors impacting Ninglang County. 展开更多
关键词 Changes of farmland Driving force Principal compon
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Intensities of human disturbance dictate the floral diversity in tropical forest:the case of a secondary forest in Benguet, Philippines 被引量:1
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作者 Domelson A.BALANGEN Melchor S.CATONES +1 位作者 Jane M.BAYENG Jones T.NAPALDET 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1575-1588,共14页
This study inventoried the floral diversity of a secondary forest in Tuba,Benguet,Philippines as affected by different intensities of human disturbance.This study is unique from other land use studies in Southeast Asi... This study inventoried the floral diversity of a secondary forest in Tuba,Benguet,Philippines as affected by different intensities of human disturbance.This study is unique from other land use studies in Southeast Asia in having conventional farms as the most disturbed land use while other sites have oil palm plantations.A total of 267 species belonging to 222 genera and 78 families was documented.Results showed that the level of human disturbance is the major factor affecting the floral diversity while the effect of elevation is secondary.The level of human disturbance is significantly associated with species richness,species composition,dominant species and biodiversity indices.Greater human disturbance,as in the case of conventional farms,results in lower species richness,predominantly weed composition,dominant weed species and lower biodiversity indices.On the other hand,lesser human disturbance(as in the case of secondary forest)leads to higher species richness,greater native species composition,dominance of indigenous species,and higher diversity indices.The most disturbed land use experienced the greatest loss of species richness,change in floristic composition and vegetation structure,as well as a shift from native to alien-dominated plant communities.These results showed that the effect of land use change is not limited to species richness but also to species composition,dominant species and biodiversity indices.Locally,the study is an important baseline data for biodiversity conservation of the Marcos Highway Watershed Forest Reserve. 展开更多
关键词 Land use change Secondary forest Conventional farming Endemic species Exotic species
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The Climate Response to Global Forest Area Changes under Different Warming Scenarios in China
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作者 Ying HUANG Anning HUANG Jie TAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期1073-1088,共16页
Human activities have notably affected the Earth’s climate through greenhouse gases(GHG), aerosol, and land use/land cover change(LULCC). To investigate the impact of forest changes on regional climate under differen... Human activities have notably affected the Earth’s climate through greenhouse gases(GHG), aerosol, and land use/land cover change(LULCC). To investigate the impact of forest changes on regional climate under different shared socioeconomic pathways(SSPs), changes in surface air temperature and precipitation over China under low and medium/high radiative forcing scenarios from 2021 to 2099 are analyzed using multimodel climate simulations from the Coupled Model Intercomparison Project Phase 6(CMIP6). Results show that the climate responses to forest changes are more significant under the low radiative forcing scenario. Deforestation would increase the mean, interannual variability, and the trend of surface air temperature under the low radiative forcing scenario, but it would decrease those indices under the medium/high radiative forcing scenario. The changes in temperature show significant spatial heterogeneity. For precipitation, under the low radiative forcing scenario, deforestation would lead to a significant increase in northern China and a significant decrease in southern China, and the effects are persistent in the near term(2021–40), middle term(2041–70), and long term(2071–99). In contrast, under the medium/high radiative forcing scenario, precipitation increases in the near term and long term over most parts of China, but it decreases in the middle term, especially in southern, northern,and northeast China. The magnitude of precipitation response to deforestation remains comparatively small. 展开更多
关键词 land use/land cover change DEforESTATION radiative forcing scenario regional climate
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Carbon Storage and Environmental Determinants in a Tropical Rainforest Landscape
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作者 Nwabueze I. Igu Jacinta U. Ezenwenyi +1 位作者 Chinero N. Ayogu Ngozi V. Okolo 《Open Journal of Ecology》 2023年第4期229-240,共12页
Tropical ecosystems sequester vast amounts of carbon but remain much varied across different landscapes. In order to provide estimates on carbon storage for the ecosystem and show the role of forest structure and envi... Tropical ecosystems sequester vast amounts of carbon but remain much varied across different landscapes. In order to provide estimates on carbon storage for the ecosystem and show the role of forest structure and environmental factors in determining aboveground and soil carbon of a rainforest landscape, forest inventory was conducted across 30 forest plots. Each of the plots measured 50 m × 50 m and was used to identify and measure tree species ≥ 10 cm diameter at breast height (DBH measured at 130cm). Soil samples were collected for up to 30 cm deep at the four edges and then the middle of each plot, bulked for analysis and tested in the laboratory. Aboveground carbon estimates ranged from 8.18 - 91.29 t/ha across the ecosystem and were similar with carbon storage in tropical landscapes. With variations in stem density, basal area and structure across the region, much of the carbon capacity across the ecosystem was much varied (F (29, 2127) = 3.794, p = 0.000). Environmental variables (mainly edaphic variables) were not positively correlated with soil carbon and did not largely determine its storage and variation. The need to reduce disturbances (which are a main driver of disparity in biomass carbon storage) across the region and across tropical ecosystems was advocated as a pathway to enhancing higher carbon sequestration. 展开更多
关键词 Climate Change CONSERVATION Degradation Land Use Change Tropical Ecosystem
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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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农地确权的政策效果“事与愿违”吗?——基于农户异质性的因果效应评估
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作者 唐忠 钟晓萍 尤婧 《安徽农业大学学报(社会科学版)》 2024年第3期1-19,共19页
农地确权的政策效果及其对农户生计决策与福祉的影响,已有的实证研究看法不一。已有研究的一般假设是政策干预与农户对政策的响应是随机的,而我国的农地确权试点区域与试点时间均具有非随机的政策选择性,因而农户的应对决策并非随机。因... 农地确权的政策效果及其对农户生计决策与福祉的影响,已有的实证研究看法不一。已有研究的一般假设是政策干预与农户对政策的响应是随机的,而我国的农地确权试点区域与试点时间均具有非随机的政策选择性,因而农户的应对决策并非随机。因此,已有研究的随机性假设需要加以检视。使用非参数匹配因果推断,全面估计农地确权对农户六类资源配置决策和福祉的影响,并分别从政策设计与实施的供给侧角度和农户面对政策变化调整其决策的需求侧角度,揭示已有实证研究结果不一致的原因。研究发现,在农业生产资料投入、劳动力向非农部门转移和获得正式贷款方面,确权政策的“顶层设计”与农户决策相匹配,有助于农户据此进行专业化分工与生产,政策效果虽然边际递减,但没有出现不一致现象。在土地流转方面,政策供给侧的选择偏差使农户流转土地的谈判交易成本上升33.3%,时间交易成本上升1.45倍;政策需求侧的农户应对行为使流转土地的谈判交易成本上升3.1倍,时间交易成本上升27.8%。供给侧与需求侧的双向偏差,加上确权的赋权增量非常有限,使政策效果与政策预期不一致,但这并不意味着确权是可有可无的,而是说明人们对确权效果的预期存在一定偏误。 展开更多
关键词 农地确权 资源配置 因果推断 制度转换成本 土地流转
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“国家—农民—村庄”视角下的中国农地集体化研究评述 被引量:1
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作者 褚刚 张清勇 《中国土地科学》 CSSCI CSCD 北大核心 2024年第4期135-144,共10页
研究目的:从国家、农民和村庄三个视角,评述国内外有关中国农地集体化的研究文献,深入探讨农地制度变迁的复杂成因与历史过程。研究方法:文献研究法。研究结果:从国家视角来看,已有研究以现代国家建设为基本脉络,将农地集体化视为一项... 研究目的:从国家、农民和村庄三个视角,评述国内外有关中国农地集体化的研究文献,深入探讨农地制度变迁的复杂成因与历史过程。研究方法:文献研究法。研究结果:从国家视角来看,已有研究以现代国家建设为基本脉络,将农地集体化视为一项革命性的制度安排,其成因可从国家推动集体化的原因和采取的措施来分析;从农民视角来看,已有研究关注农民的能动性,既分析了他们在情感、认知、观念和行为上的变化,也可从中见证国家治理现代化的实践探索;作为连接国家与农民的中介,村庄兼具文化上的“共同体”和利益上的“博弈场”两种属性,该视角侧重考察农地集体化的微观机制,分析各主体在文化和利益驱动下的互动关系。研究结论:集体化是准确把握我国农地制度为何坚持“集体所有”不动摇的关键,未来可从强化学科交叉、促进理论提炼,超越单一视角、寻求整体理解,以及突破方法局限、增进多元认知等方面入手,以便在更广阔的理论对话上有所提升,构建更具中国特色的理论表达。 展开更多
关键词 农地 集体化 制度变迁 评述
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Changes of soil organic carbon and nitrogen in forage grass fields,citrus orchard and coniferous forests 被引量:8
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作者 王效举 李法云 +1 位作者 范志平 熊在平 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期29-32,J002,共5页
Dynamic quantitative assessment of soil organic C and N is an available approach to understand the exact impact of land management on soils fertility. In this study the biomass of plants and content of soil organic C ... Dynamic quantitative assessment of soil organic C and N is an available approach to understand the exact impact of land management on soils fertility. In this study the biomass of plants and content of soil organic C and N were compared in four typical land use systems which were planted with Ryegrass (Lolium multiflorum Lam.), Bahiagrass (Paspalum notatum Flugge.), Citrus (Citrus reticulata Blanco.), and Masson pine (Pinus Massoniana Lamb.) during 10 years in south China. Although biomass of plants in these four land use systems was nearly at the same level in the former investigation, total biomass for Ryegrass (RG), Bahiagrass (BG) was 3.68 and 3.75 times higher than that for Citrus (CT), and 2.06 and 2.14 times higher than that for Masson pine (MP) over 10 years of cultivation, respectively. Especially, underground total biomass for both RG and BG was over 10 times larger than that for CT and MP, indicating that forage grasses was much more beneficial to increase organic C and N storage in soils than CT and MP. The change content of soil organic C and N mainly occurred within soil depth of the 0–40 cm. The increased content of soil organic carbon and nitrogen was for 1.5 t·hm?2 and 0.2 t·hm?2 in the soil with planting RG and BG, and was for 1.2 t·hm?2 and 0.02 t·hm?2 in the soil with planting CT. An average loss was for 0.4 t·hm?2 and 0.04 t·hm?2 in the soil with planting MP during 10-year period. Keywords Soil organic carbon - Soil organic nitrogen - Dynamic change - Land use - Quantitative assessment CLC number S153.61 Document code A Foundation item: This research was partly supported by National Natural Science Foundation of China (30100144), and by Scientific Committee of Shenyang City (1011501900).Biography: WANG Xiao-ju (1967-), mail, Ph.D. Researcher in Center for Environmental Science in Saitama. Saitama Prefecture 347 0115, Japan.Responsible editor: Zhu Hong 展开更多
关键词 Soil organic carbon Soil organic nitrogen Dynamic change Land use Quantitative assessment
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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change 被引量:1
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作者 Lingyun He Lei Zhong +3 位作者 Yaoming Ma Yuting Qi Jie Liu Peizhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期22-27,共6页
The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of th... The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau. 展开更多
关键词 Carbon and water flux Water use efficiency Alpine meadow Biome-BGC model Climate change
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Livelihood Strategy and Farmland Use in Xinping County of Yuanjiang Dry-hot Valley 被引量:1
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作者 赵文娟 杨世龙 王潇 《Agricultural Science & Technology》 CAS 2016年第4期977-982,共6页
Methods of participatory rural appraisal and mathematical statistics were adopted to study livelihood diversification, livelihood strategy and farmland use of the four types of farmers in Xinping County of Yuanjiang d... Methods of participatory rural appraisal and mathematical statistics were adopted to study livelihood diversification, livelihood strategy and farmland use of the four types of farmers in Xinping County of Yuanjiang dry-hot valley with field survey data. The results showed as follows: firstly, as farmers are transforming from pure agriculture to non-agriculture, their agricultural livelihood diversification index will decrease, while non-agricultural livelihood diversification index will increase. In term of livelihood activities, pure agricultural farmers are exclusively engaged in agricultural activities, agricultural-dominant and non-agricultural-dominant farmers are engaged in both agricultural and non-agricultural ones, while non-agricultural farmers are basically engaged in off-farm activities. Secondly, as for crops planted, pure agricultural and agricultural-dominant farmers tend to choose those crops with more investment,shorter growth period and higher value, meanwhile non-agricultural-dominant farmers tend to choose crops with less investment, simpler management and longer growth period. Thirdly, to cope with current problems in farming, pure agricultural farmers will adopt measures such as changing planting structure, maintaining or expanding planting scale, increasing planting investment and renting in more land to promote the development of farming; agriculture-dominant farmers will adopt measures such as changing planting structure, reducing planting scale, maintaining planting investment, renting in and taking back the leased land as well as engaging in non-agricultural activities to overcome the difficulties faced; while non-agricultural-dominant farmers will adopt measures such as reducing both planting scale and investment,changing planting structure and engaging in farmland transfer as well as various offfarm activities to avoid livelihood risks. 展开更多
关键词 Xinping County of Yuanjiang dry-hot valley Farmers' livelihood activities farmland use
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Geo-information Tupu Analysis of Land Use Change in Haihe River Basin 被引量:2
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作者 朱占永 郭伟志 张海力 《Agricultural Science & Technology》 CAS 2012年第5期1139-1144,共6页
[Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial dist... [Objective] This study was to provide basis for the scientific management of land use in Haihe River Basin (HRB) through the quantitative exploration of the land use conversion, changes of intensity and spatial distribution in this region. [Method] With the support of remote sensing technology and geographic information technology, the land use maps of the study area in 40 years (1970-2010) were in- terpreted and plotted. Four kinds of tupu, namely, land use change tupu, process tupu, arising tupu and evolution mode tupu were built through the spatial overlay of the land use maps to analyze the change rules of land use patterns. [Result] The conversion of arable land to construction land was the main characteristics of land use changes in HRB for the 40 years; the area of non-stable region accounted for 35% of the total, indicating that the land use changed remarkably, thus, it was nec- essary to strengthen the scientific land management in HRB; the new conversions to all land use patterns were all the lowest in 1980-1990, indicating that land use changed slowly during this period. [Conclusion] The results indicate that, compared with conventional transfer matrix method, geo-information tupu has obvious advantage in analyzing land use changes that it can demonstrate the spatial distribution of interest region, display the multi-dimensional spatial information. 展开更多
关键词 Haihe river basin Tupu analysis Land use change Evolution mode
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Analysis and Simulation for Landscape Pattern Changes of Land Use in Wuzhong District, Suzhou City 被引量:1
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作者 汪煜 吴国平 何林艳 《Journal of Landscape Research》 2010年第2期39-42,46,共5页
Based on analyzing the changes of land use in Wuzhong District, Suzhou City from 2005 to 2008, temporal and spatial changes of land use from 2008 to 2020 were analyzed by using the model CLUE-S and, from the perspecti... Based on analyzing the changes of land use in Wuzhong District, Suzhou City from 2005 to 2008, temporal and spatial changes of land use from 2008 to 2020 were analyzed by using the model CLUE-S and, from the perspective of landscape ecology, future landscape pattern changes of land use in Wuzhong District were also quantitatively discussed by utilizing landscape indices. The results indicated that there was a large variation range of land use in Wuzhong District from 2005 to 2008 and massive farmland and woodland were transformed into construction land and gardens. Guided by the policy of saving intensive land and protecting farmland, future variation range of land use will get smaller obviously. The fragmentation degree for farmland, woodland and water area will get decreased but will get increased relatively for construction land. In general, all landscapes tend to a balanced development. 展开更多
关键词 Changes of land use CLUE-S Landscape pattern
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