Spatially Heterogeneous Response of Carbon Storage to Land Use Changes in Pearl River Delta Urban Agglomeration, China

Carbon storage of terrestrial ecosystems plays a vital role in advancing carbon neutrality. Better understanding of how land use changes affect carbon storage in urban agglomeration will provide valuable guidance for policymakers in developing effective regional conservation policies. Taking the Pearl River Delta Urban Agglomeration(PRDUA) in China as an example, we examined the heterogeneous response of carbon storage to land use changes in 1990–2018 from a combined view of administrative units and physical entities. The results indicate that the primary change in land use was due to the expansion of construction land(5897.16 km2). The carbon storage in PRDUA decreased from 767.34 Tg C in 1990 to 725.42 Tg C in 2018 with a spatial pattern of high wings and the low middle. The carbon storage loss was largely attributed to construction land expansion(55.74%), followed by forest degradation(54.81%). Changes in carbon storage showed significant divergences in different sized cities and hierarchical boundaries. The coefficients of geographically weighted regression(GWR) reveal that the alteration in carbon storage in Guangzhou City was more responsive to changes in construction land(-0.11) compared to other cities, while that in Shenzhen was mainly affected by the dynamics of forest land(8.32). The change in carbon storage was primarily influenced by the conversion of farmland within urban extent(5.05) and the degradation of forest land in rural areas(5.82). Carbon storage changes were less sensitive to the expansion of construction land in the urban center, urban built-up area, and ex-urban built-up area, with the corresponding GWR coefficients of 0.19, 0.04, and 0.02. This study necessitates the differentiated protection strategies of carbon storage in urban agglomerations.

Impact of Land Use Changes on Surface Warming in China

Land use changes such as urbanization, agriculture, pasturing, deforestation, desertification and irrigation can change the land surface heat flux directly, and also change the atmospheric circulation indirectly, and therefore affect the local temperature. But it is difficult to separate their effects from climate trends such as greenhouse-gas effects. Comparing the decadal trends of the observation station data with those of the NCEP/NCAR Reanalysis (NNR) data provides a good method to separate the effects because the NNR is insensitive to land surface changes. The effects of urbanization and other land use changes over China are estimated by using the difference between the station and the NNR surface temperature trends. Our results show that urbanization and other land use changes may contribute to the observed 0.12℃ (10yr)-1 increase for daily mean surface temperature, and the0.20℃ (10yr)-1 and 0.03℃ (10 yr)-1 increases for the daily minimum and maximum surface temperatures, respectively. The urban heat island effect and the effects of other land-use changes may also play an important role in the diurnal temperature range change. The spatial pattern of the differences in trends shows a marked heterogeneity. The land surface degradation such as deforestation and desertification due to human activities over northern China, and rapidly-developed urbanization over southern China, may have mostly contributed to the increases at stations north of about 38°N and in Southeast China, respectively. Furthermore, the vegetation cover increase due to irrigation and fertilization may have contributed to the decreasing trend of surface temperature over the lower Yellow River Basin. The study illustrates the possible impacts of land use changes on surface temperature over China.

Impacts of land use changes on groundwater resources in the Heihe River Basin

Land use and land cover changes have a great impact on the regional hydrological process. Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the impacts of land use changes on the groundwater system in the middle reach of Heihe River Basin in recent three decades are analyzed by the perspective of groundwater recharge and discharge system. The results indicate that with the different intensities of land use changes, the impacts on the groundwater recharge were 2.602 × 10^8 m^3/a in the former 15 years （1969-1985） and 0.218 × 10^8 m^3/a in the latter 15 years （1986-2000）, and the impacts on the groundwater discharge were 2.035 × 10^8 m^3/a and 4.91 × 10^8 m^3/a respectively. When the groundwater exploitation was in a reasonable range less than 3.0 × 10^8 m^3/a, the land use changes could control the changes of regional groundwater resources. Influenced by the land use changes and the large-scale exploitation in the recent decade, the groundwater resources present apparently regional differences in Zhangye region. Realizing the impact of land use changes on groundwater system and the characteristics of spatial-temporal variations of regional groundwater resources would be very important for reasonably utilizing and managing water and soil resources.

Spatiotemporal Urban Land Use Changes in the Changzhutan Region of Hunan Province in China

The Changzhutan region in the north-central part of Hunan Province in China has experienced a rapid urbanization in the past few decades that has led to substantial changes in its environment. In 2007, the National Development and Reform Commission of China designated the metropolitan district of Changsha City, Zhuzhou City, and Xiangtan City of this region as the fourth National Demonstration Area where economic development should be implemented in harmony with resource-saving and environment-friendly land use practices. The research, focus of this article will be on quantifying the spatial pattern of urban land use change which not only can provide an assessments and predictions of future environmental effects, but also will serve as a scientific basis for the development of urban sustainability. This paper integrates historical Landsat TM imagery, geographical information system (GIS) and socioeconomic data to determine the spatiotemporal urban land use dynamics and conversion of land use in response to the rapid urbanization of a select group of cities in China from 1990 to 2007. The approach is based on Principle Component Analysis to determine and model the relationship between the socioeconomic factors and land use/cover change (LUCC) for identifying the driving forces. The results indicate that land cover of the Changzhutan region mainly consists of forestland and cropland which accounted for about 93% of the total land area. During the 1990-2007 study period, the urban areas and water bodies increased by 46,297 ha and 775 ha, respectively, while forestland, cropland, and grassland decreased appreciably by 22,580 ha, 21,808 ha, and 5618 ha, respectively. Moreover, the urban land area during the 2000-2007 period increased by five times as much as that during the 1990-2000 period. The land use dynamic degree of Changsha City is the largest one followed by that for Xiangtan and Zhuzhou Cities. During this study period, the land use comprehensive intensity index increased and followed the sequence Xiangtan > Changsha > Zhuzhou. The changes were attributed to economic development, population growth, infrastructure improvements and construction, and land use policies. To address the negative or eco-environmental deleterious effects of these changes, landscape ecology plan, population growth control, and the development of an ecological friendly agriculture were suggested.

Relationship Between Land Use Changes and the Production of Dust Sources in Kermanshah Province,Iran

Recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the environment.Taking Kermanshah Province,Iran as study area,dusty days from 2008 to 2015 were selected and dust sources were identified applying thermal-infrared dust index(TDI),hybrid single-particle lagrangian integrated trajectory(HYSPLIT),false color composite(FCC)and true color composite(TCC)of MODerate resolution Imaging Spectroradiometer(MODIS)images.Afterwards,the land use change map was produced using Landsat images in 2000 and 2015.Then,the distribution and frequency of the sources in each land-use change class and important dust production areas were specified.Eventually,two non-parametric tests including Chisquare and Kruskal-Wallis were applied to examine the relationship between LUC and dust sources.Results indicated that the distribution of dust sources was not identical in the study area,and the sources were mainly generated in the areas where land-use change had occurred.In fact,different classes of LUC have different contributions to dust production,and the highest contribution refers to the deflation in gentle slope areas and lowlands where the rangeland has been converted into agriculture land.The findings from this study are useful to manage and control dust in the identified sources.

Study on Land Use Changes in the Yellow River Delta from 1980 to 2010

Taking the Yellow River Delta for example, this paper applied remote sensing and GIS to explore land use changes in the local area from 1980 to 2010. The results showed that arable land, and urban and rural construction land were major land use types in the Yellow River Delta, unused land also took a large ratio; land use changes occurred mainly in coastal regions, in terms of change matrix, 25.46% of the grassland was reclaimed as arable land, unused land also witnessed great changes, specifi cally, 11.14% turned to arable land, 23.25% to construction land. This study provided references for the land use planning and development of the local area.

Analysis of Land Use Changes in the Watershed of Nansi Lake,Shandong Province

Change of land use is related to regional food security and ecological security.This study analyzed structural changes,quantity changes and spatial changes of land resource utilization in the watershed of the Nansi Lake,Shandong Province from 2000 to 2012 on the basis of land use investigation data and relevant socio-economic data in the study period.It is to disclose the problems in the utilization of local land resources,and provide scientific support for the scientific management of land resources and sustainable development of social economy.

Upshot of Sprawl Incidence on Pattern of Land Use Changes and Building Physiognomies in Akure Region, Nigeria

This study investigates the upshot of sprawl incidence on pattern of land use changes and building physiognomies in Akure and its environs.Using social survey research method(SSRM)to investigate the upshot,data were gathered via structured questionnaires on selected households in the region,involving Akure municipal and eight contiguous communities.Basically,the survey method involves interview,personal observation and photo-snaps to elucidate existing situation in the region.Average households’population in Akure municipal was estimated at 95,232 while 14,794 was estimated in the selected eight contiguous communities.From this,a sample of 1%was systematically selected,which amounted to 1100 sampled households.Findings show regular massive inflow of people into the city due to unguided expansions that have serious sway on land use determinant in the city and its contiguous communities.It also has significant influence on variation in building arrangements and facility distribution across the region.To mitigate this,the study advocates proactive efforts of stakeholders in urban management to employing inventive measures over private and public lands in logical manners.It also suggests the espousal of regional development programs to checkmate the rate of peoples’incursion into Akure,being the state capital.Local government headquarters and other major towns in the region should be reinforced with functional basic facilities to curtail the excessive influx into the city.

Historical Changes and Multi-scenario Prediction of Land Use and Terrestrial Ecosystem Carbon Storage in China

Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management policies.The Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and 2060.Based on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to 2060.The findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest area.This changing trend is projected to continue under the PCS from 2020 to 2060.Under the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously decrease.Carbon loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and grassland.In the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 scenario.Carbon loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary drivers.In the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban land.These research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.

Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China

Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to 2020.Through trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC changes.We further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and grassland.During the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change types.Besides the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change area.The period 2010-2020 witnessed more active LULC changes compared to the period 2000-2010.The LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the JRB.Influential driving factors on LULC changes included slope,GDP,and distance from highways.The interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to 2020.This comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management of LULC in the JRB.

Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum

The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale.

Response of ecosystem carbon storage to land use change from 1985 to 2050 in the Ningxia Section of Yellow River Basin,China

Regional sustainable development necessitates a holistic understanding of spatiotemporal variations in ecosystem carbon storage(ECS),particularly in ecologically sensitive areas with arid and semi-arid climate.In this study,we calculated the ECS in the Ningxia Section of Yellow River Basin,China from 1985 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model based on land use data.We further predicted the spatial distribution of ECS in 2050 under four land use scenarios:natural development scenario(NDS),ecological protection scenario(EPS),cultivated land protection scenario(CPS),and urban development scenario(UDS)using the patch-generating land use simulation(PLUS)model,and quantified the influences of natural and human factors on the spatial differentiation of ECS using the geographical detector(Geodetector).Results showed that the total ECS of the study area initially increased from 1985 until reaching a peak at 402.36×10^(6) t in 2010,followed by a decreasing trend to 2050.The spatial distribution of ECS was characterized by high values in the eastern and southern parts of the study area,and low values in the western and northern parts.Between 1985 and 2020,land use changes occurred mainly through the expansion of cultivated land,woodland,and construction land at the expense of unused land.The total ECS in 2050 under different land use scenarios(ranked as EPS>CPS>NDS>UDS)would be lower than that in 2020.Nighttime light was the largest contributor to the spatial differentiation of ECS,with soil type and annual mean temperature being the major natural driving factors.Findings of this study could provide guidance on the ecological construction and high-quality development in arid and semi-arid areas.

Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta

The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.

Land use and cover change and influencing factor analysis in the Shiyang River Basin,China

Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and social economy.Rapid economic development and climate change have resulted in significant changes in land use and cover.The Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant climate change and LUCC over the past few decades.In this study,we used the random forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat images.We validated the land use and cover data in 2015 from the random forest classification results(this study),the high-resolution dataset of annual global land cover from 2000 to 2015(AGLC-2000-2015),the global 30 m land cover classification with a fine classification system(GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this study.Furthermore,we explored and compared the spatiotemporal patterns of LUCC in the upper,middle,and lower reaches of the Shiyang River Basin over the past 30 years,and employed the random forest importance ranking method to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,temperature,and surface soil moisture)and anthropogenic(nighttime light,gross domestic product(GDP),and population)factors.The results indicated that the random forest classification results for land use and cover in the Shiyang River Basin in 2015 outperformed the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial validations.Moreover,the classification results in this study exhibited a high level of agreement with the ground truth features.From 1991 to 2020,the area of bare land exhibited a decreasing trend,with changes primarily occurring in the middle and lower reaches of the basin.The area of grassland initially decreased and then increased,with changes occurring mainly in the upper and middle reaches of the basin.In contrast,the area of cropland initially increased and then decreased,with changes occurring in the middle and lower reaches.The LUCC was influenced by both natural and anthropogenic factors.Climatic factors and population contributed significantly to LUCC,and the importance values of evapotranspiration,precipitation,temperature,and population were 22.12%,32.41%,21.89%,and 19.65%,respectively.Moreover,policy interventions also played an important role.Land use and cover in the Shiyang River Basin exhibited fluctuating changes over the past 30 years,with the ecological environment improving in the last 10 years.This suggests that governance efforts in the study area have had some effects,and the government can continue to move in this direction in the future.The findings can provide crucial insights for related research and regional sustainable development in the Shiyang River Basin and other similar arid and semi-arid areas.

Dynamics of the eco-environmental quality in response to land use changes in rapidly urbanizing areas: A case study of Wuhan, China from 2000 to 2018

The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality.Investigating urban land use changes and their eco-environmental quality responses can provide theoretical support and a decision-making basis for sustainable and high-quality development in rapidly urbanizing areas.Taking Wuhan,China,as the study area,this paper extracts land use information using Landsat satellite remote sensing images and a support vector machine classification.Based on this,a remote sensing-based ecological index evaluation model including humidity,greenness,dryness and heat is constructed to explore the changes in land use and their eco-environmental quality responses from 2000 to 2018.The results show that(1)the structure,extent and spatial layout of land use in Wuhan from 2000 to 2018 have undergone tremendous changes under rapid urbanization,and the change of construction land is the greatest among all land use types;(2)the overall quality of eco-environment in Wuhan continues to improve as the scale of the improved eco-environment areas is greater than that of the deteriorated areas.The direction and magnitude of the impact of each indicator on the eco-environmental quality are different;(3)the improvement or deterioration of eco-environmental quality is closely related to the changes of different land use types within the study area.The eco-environmental quality shows significant spatial heterogeneity,especially between the main urban areas and the suburban areas.This paper argues that reasonably adjusting the land use structure can serve to maintain or even improve the quality of the regional eco-environment.Finally,this study puts forward suggestions for the coordinated development of land use and the eco-environment in rapidly urbanizing areas.

Land Use Land Cover Analysis for Godavari Basin in Maharashtra Using Geographical Information System and Remote Sensing

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.

Projected land use changes in the Qinghai-Tibet Plateau at the carbon peak and carbon neutrality targets

Based on historical land use for eight periods from 1980 to 2020 and the projected land use under seven Shared Socioeconomic Pathways(SSPs:SSP1-1.9,SSP1-2.6,SSP2-4.5,SSP3-7.0,SSP4-3.4,SSP4-6.0,and SSP5-8.5)from 2021 to 2100,we conducted a study on past and future land use changes in the Qinghai-Tibet Plateau(QTP).This work aims to reveal the land use changes during the carbon peak(2021-2040)and carbon neutrality(2051-2070)periods and at the end of the 21st century(2081-2100).The results show that:(1)in the historical period(1980-2020),the land use types in the QTP were grassland(1475×10^(3)km^(2),58.2%),barren land(685×10^(3)km^(2),27.0%),forest land(243×10^(3)km^(2),9.6%),water(114×10^(3)km^(2),4.5%),cropland(18.6×10^(3)km^(2),0.7%)and urban land(0.3×10^(3)km^(2),0.01%).(2)Relative to the baseline period(1995-2014),the area of grassland is projected to decrease by 0.7%(SSP4-6.0)-5.4%(SSP2-4.5)(0.5-3.9%of the total area of the QTP),2.8%(SSP4-6.0)-12.5%(SSP3-7.0)(2.1-9.4%of the total area of the QTP)and 6.1%(SSP4-6.0)-21.7%(SSP4-3.4)(4.6-16.4%of the total area of the QTP)in the future three periods.In contrast,the forest land area is projected to increase,by approximately 2.5%(SSP4-6.0)to 30.1%(SSP3-7.0)(0.3-4.3%of the total area of the QTP),9.2%(SSP4-6.0)to 56.5%(SSP2-4.5)(1.3-8.0%of the total area of the QTP),and 21.2%(SSP4-6.0)to 72.8%(SSP2-4.5)(3.0-10.2%of the total area of the QTP)in the future three periods,respectively.(3)Approximately 0.4(SSP4-6.0)to 6.9%(SSP5-8.5),0.9(SSP4-6.0)to 2.7%(SSP4-3.4),and 0.04(SSP5-8.5)to 3.5%(SSP1-1.9)of land is expected to convert from grassland to forest land in the future three periods,respectively.The shift from grassland to forest land area is likely to enhance the carbon sink potential of the QTP in the future period.

Land Use/Cover and Naturalness Changes for Watershed Environmental Management(Southeastern Brazil)

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.

Land use changes in Istanbul＇s Black Sea coastal regions between 1987 and 2007

Recently, important land use changes have occurred in the Black Sea coastal regions of istanbul due to urban growth and population increases. The objective of this study was to determine changes in land use in the Black Sea coastal regions of Jstanbul between 1987 and 2007. Landsat 30 m satellite images from 1987 and 2007 are used in the study. The study area is 1000 m in width from the coastline to the land and the study has been carried out using the controlled classification method to classify areas into residential, agricultural, forest, bare land, brush/grassland, and lake/pond land classes. Land use changes between 1987 and 2007 were analysed in detail. Residential areas of the Black Sea coastal regions of istanbul increased by 122% over the two decades. Also an increase of 55% in agriculture areas was observed, while there were decreases of 26% in forest areas and 15% in free land. A 21% increase in the area of brush and grassland took place. Furthermore 79% of the study area was covered by residential areas in 2007. It is probable that pressure on the Jstanbul coastal regions will continue due to migraton and rapid urbanization. Therefore, Istanbul＇s Black Sea coastal regions should be maintained using a sustainable coastal management plan.

Impacts of land use/cover change on water balance by using the SWAT model in a typical loess hilly watershed of China

Land use/cover change(LUCC)plays a key role in altering surface hydrology and water balance,finally affect-ing the security and availability of water resources.However,mechanisms underlying LUCC determination of water-balance processes at the basin scale remain unclear.In this study,the Soil and Water Assessment Tool(SWAT)model and partial least squares regression were used to detect the effects of LUCC on hydrology and water components in the Zuli River Basin(ZRB),a typical watershed of the Yellow River Basin.In general,three recommended coefficients(R^(2)and E ns greater than 0.5,and P bias less than 20%)indicated that the output results of the SWAT model were reliable and that the model was effective for the ZRB.Then,several key findings were obtained.First,LUCC in the ZRB was characterized by a significant increase in forest(21.61%)and settlement(23.52%)and a slight reduction in cropland(-1.35%),resulting in a 4.93%increase in evapotranspiration and a clear decline in surface runoffand water yield by 15.68%and 2.95%at the whole basin scale,respectively.Second,at the sub-basin scale,surface runoffand water yield increased by 14.26%-36.15%and 5.13%-15.55%,respectively,mainly due to settlement increases.Last,partial least squares regression indicated that urbanization was the most significant contributor to runoffchange,and evapotranspiration change was mainly driven by forest expansion.These conclusions are significant for understanding the relationship between LUCC and water balance,which can provide meaningful information for managing water resources and the long-term sustainability of such watersheds.