Land cover analysis along semi-arid transects in Asia

The study aimed to assess the changes that have occurred in land use and land cover within the Maasai Mara landscape using remote sensed data from 1997 to 2017; examine the elephant distribution in relation to land use and land cover changes within the Mara landscape and to determine changes in elephant home ranges in relation to Land use and cover changes in the Mara landscape. In examining the land use and land cover changes on the elephant ranges and distribution, an integrated methodological approach was employed in which the changes that have taken place within the study area over a period of 20 years was determined by analysis involving a 10-year changes in land use and land cover using three epochs from 1997, 2007 and 2017 to generate six land use classes. The Maasai Mara Landscape (MML) supports one of the richest wildlife populations remaining on earth but over the last century, has experienced transformation notably through conversion of former rangelands into croplands. Elephants have both temporal and spatial requirements, which if not provided, render them vulnerable to the land-use practices. The study assessed land use and vegetation cover changes that have occurred and their effects on the elephant movements and distribution within the MML using an integrated methodological approach. The analysis revealed changes in land use and land cover classes over a period of 20 years for the three epochs, from 1997, 2007 and 2017. Elephant’s distribution has been restricted to areas of high vegetation densities within specific habitats hence accelerating the rate of habitat destruction and degradation due to their high densities. These changes have drastically reduced forage for elephants necessitating them to travel longer distances out of their home range in search for food. Human beings have caused land use and cover changes which have detrimental impacts on the ecosystem and ecosystem services. The Maasai Mara landscape supports one of the richest wildlife populations remaining on earth but over the last century, it has experienced land transformation notably through conversion of former rangelands used mainly for tourism and production of grains such as wheat. Land outside the national parks and the reserve is important to the future of elephant existence in Kenya. Little is known about how human occupation on these landscapes negatively affects elephants (Loxodonta africana) habitats, movement and ranges. This has been confirmed by the current continuous demarcation/fencing of land in most areas in Narok County. Elephants like other landscape species, have both temporal and spatial requirements, which if not provided, will render them vulnerable to the land use practices of people. The study aimed to assess the changes that have occurred in land use and land cover within the Maasai Mara landscape using remote sensed data from 1997 to 2017; examine the elephant distribution in relation to land use and land cover changes within the Mara landscape and to determine changes in elephant home ranges in relation to Land use and cover changes in the Mara landscape. The paper describes the different changes that have taken place within the MML and how these changes have affected elephant populations, their trend and distribution within the MML. In examining the land use and land cover changes on the elephant ranges and distribution, an integrated methodological approach was employed in which the changes that have taken place within the study area over a period of 20 years was determined by analysis involving a 10-year changes in land use and land cover using three epochs from 1997, 2007 and 2017 to generate six land use classes. The study found out that there were significant changes of various classes across the years. Forest, water and open shrubs coverages decreased from 1997 to 2017. Classification noted a serious problem within the study area of continuous increase of bare ground coverage across the study years. Elephant populations have been increasing within the area .at an annual rate of 2.69%. The animals are distributed all over the landscape. Distribution of elephants has been restricted to high densities within a specific habitat hence accelerating rate of habitat destruction and degradation due to their high densities within a specific habitat. These changes have reduced drastically foliage for elephants thus necessitating them to travel longer distances in search and as a result increases elephant home ranges.

Forest and wood land ecosystems in Tanzania occupy more than 45% of the land area, more than two thirds of which made up of the Miombo woodland. The main form of land use in the Miombo region has long been shifting and small-scale sedentary cultivation. The lack of infrastructure and prevalence of deadly diseases such as malaria and trypanosiomiasis have long limited extensive clearance for cultivation, livestock farming and settlements. However, due to positives changes in the socio-economical, political and technological setup in miombo region, the types and intensity of land use are now changing. This paper discusses preliminary results from a study conducted with the aim of contributing to the understanding of dynamics of land cover and use changes in miombo woodlands of eastern Tanzania. The study area comprises four villages around the “Kitulangalo Forest Reserve”, 140 km west of Dar es Salaam on either side of the Morogoro-Dar es Salaam highway. Landsat MSS satellite images of July 1975, Landsat TM satellite images of July 2000 were used to assess land cover changes between 1975 and 2000. Participatory Rural Appraisal (PRA), questionnaire survey and checklists for key informants were the major methods used for collecting socio-economic data. The land cover/use class of woodland with scattered cultivation has recorded the highest percentage of change between July 1975 and July 2000. While all other classes have registered positive changes, only the closed woodland class has had negative change meaning that this class has been decreasing in favour of other land cover/use classes. Recent land cover and use changes are drastic in the study area. These changes have been triggered largely by varied factors including mainly increased population density and subsequent economic activities. Economic activities including charcoal business, shifting cultivation, opening up of improved highway and pastoralism in the study area have greatly contributed to deforestation and woodland degradation. In light of these findings, there is need for: (1) Adequate land use planning and survey of village lands so as to avoid exacerbation of land use conflict and environmental degradation in the study area. (2) Agrarian reforms to eliminate open access regimes to natural resources. (3) Enforcement of fiscal policies related to the extraction of natural resource products such as timber and charcoal so as to reduce pressure on woodlands. Keywords: land use – cover change – Kitulangalo – miombo woodlands

Introduction: Landscape changes can be monitored using geotechnologies through land use and land cover management over time, which helps identify and understand transformations in the landscape and supports decision-making processes. This study aims to analyze land use and cover change in the Portal do Sertão Identity Territory, Bahia, and to relate the possible causes that have currently induced such changes. This territory, located in the Caatinga biome, has its economic activities mainly concentrated in the primary and tertiary sectors. Remote Sensing (RS) and Geographic Information Systems (GIS) were employed to monitor changes in land use and cover in this territory from 1985 to 2022, using images from the MapBiomas Collection 8.0. During the study period, there was a reduction in the area used for agriculture and livestock and a significant increase in urbanization, with an urban area growth of more than 380%. Additionally, water bodies also expanded, mainly due to the construction of the Pedra do Cavalo Hydroelectric Plant in 1985, which resulted in a larger flooded area. Forest formations, although fluctuating over the years, were negatively impacted by agricultural expansion and urbanization. Therefore, the use of geotechnologies such as RS and GIS proves to be an effective tool for environmental monitoring, enabling the identification and management of land use changes and contributing to the mitigation of environmental impacts. Objective: The aim of this study is to investigate land use and land cover changes in the Portal do Sertão Identity Territory, in order to identify the possible causes currently driving these transformations. . Theoretical Framework: Remote Sensing (RS) is a science that maps Earth’s surface targets using sensors without direct contact. It is an essential tool for understanding and monitoring land use and land cover changes, providing critical information for decision-making from multiple perspectives. Its integration with Geographic Information Systems (GIS) enhances the spatiotemporal analysis of processes such as environmental and territorial degradation. The concept of "Identity Territory," developed by SEPLAN-BA, considers sociocultural, economic, and geographic factors for territorial organization. Institutionalized by state decrees, it divides Bahia into 27 territories to promote regional public policies. The articulation of RS, GIS, and the Identity Territory framework offers an effective approach to understanding and managing land use changes in the Portal do Sertão. Method: This study analyzed land use and land cover changes in the Portal do Sertão Identity Territory, composed of 27 municipalities in Bahia, aiming to understand the possible driving forces behind these changes. Satellite images from the MapBiomas Brazil Collection 8.0 were used for the years 1985, 1990, 1995, 2000, 2005, 2010, 2015, 2020, and 2022. A GIS environment was used to reclassify the images into four classes based on the MapBiomas classification: Forest Formation, Agriculture, Urban Area, and Water Bodies. The total area per class was quantified for each year, and land use transition maps were generated for spatial analysis. Results and Discussion: The analysis revealed that between 1985 and 2022, the Portal do Sertão Identity Territory experienced significant transformations in land use and cover. There was a notable reduction in agricultural and livestock areas and a sharp increase in urban development, particularly in Feira de Santana and neighboring municipalities, driven by industrialization, public policies, and real estate expansion. Forest cover fluctuated, while water bodies increased following the construction of the Pedra do Cavalo Hydroelectric Plant in 1985. These changes reflect processes of urbanization, rural exodus, and territorial reconfiguration influenced by economic, social, and infrastructural factors. Research Implications: This research provides essential technical and spatial support for territorial planning in the region, assisting local governments and institutions in making more informed decisions based on historical land use patterns. The findings highlight the importance of integrated public policies focused on territorial planning, environmental preservation, and housing, especially in light of rapid population growth. Originality/Value: This study contributes to the literature by analyzing the drivers of land use change using open-access data from MapBiomas. Its significance lies in the integration of Remote Sensing and GIS to investigate land use trends in the Portal do Sertão over the past decades, providing strategic insights to support public policy development and more effective territorial planning.

The Tibetan Plateau (TP) is an important ecological security barrier for China and, indeed, for all Asia. Land use and land cover changes in the plateau not only affect the ecological environment and regional development of the plateau itself but also affect the stability and economic development of ecosystems in eastern China and other parts of Asia. This paper is based on an examination of the achievements of land use and cover change in the TP and a reanalysis of data including that of Climate Change Initiative Land Cover from 1992 to 2015; land use data provided by the Resource and Environmental Science Data Center of the Chinese Academy of Sciences for 1995, 2000, 2010 and 2015; and statistical data from Qinghai and Tibet. The paper analyzes the overall characteristics of land use and land cover changes in the TP and the spatial and temporal processes and their driving forces of land use and land cover change in typical regions and land types. This research is important not only for land change science and global change research but also for the promotion of the plateau and its adjacent areas. In recent decades, research has shown that the land use and land cover structure of the TP is stable, and the proportion of first-level land use type change was less than 7% from 1992 to 2015. Most of these changes are single time changes, with multiple land change occurring only in 1.85% of the total change area. The quality of land cover has been improved in areas where no land type change occurred. The Normalized Difference Vegetation Index (NDVI) showed an increasing trend in 24.45% of the area and a decreasing trend in only 1.31% of the area. The area of cultivated land, forest, grassland, wetland, and construction land on the plateau has increased, whereas bare land, glacier, and snow cover area has decreased. In most parts of the TP, the quality of alpine grassland has improved; however, in some areas, it has degraded at a local scale. Most of the woodland has recovered well after phased changes. Prior to 1980, there was a rapid increase in cultivated land area, but this has since become stable with only minor increases. However, the utilization intensity of cultivated land has increased significantly in recent years. Construction land has expanded significantly, and the recent growth rate has accelerated since 2010. Both the increasing speed of change and the construction land area in Qinghai Province are higher than in Tibet. There has been a general trend of a slight decrease in bare land change. In densely populated areas in the Yellow River-Huangshui River Valley and the One-River-Two-Tributaries area, land types that are closely related to human utilization such as construction land, cultivated land, and artificial woodland have undergone obvious changes. In pastoral areas, such as the Northern Tibetan Plateau and the Source Regions of The Three Rivers, overgrazing and ecological construction have significantly affected land cover. In the Qomolangma National Nature Preserve, land use types are diverse; changes are complex; and land cover is more sensitive to both climate change and human activity. There are limitations to the study of land change in the plateau, such as the difficulty of meeting the needs of ecological construction with existing data and the lack of in-depth understanding of the process of land use change and its environmental effects. Field monitoring and remote sensing techniques must be strengthened in order to clarify the process of land use intensity change and its impact on the ecological environment of the TP. These improvements will better serve the construction of an ecological security barrier and the sustainable development of the region.

Lilongwe, Malawi’s capital city, has grown nearly tenfold in the last 40 years with a 4-5% annual population growth rate, and the city’s population is projected to double over the next decade. Rural to urban migration and natural increase are the driving factors of the city’s urban expansion. Characterised by the urbanisation of poverty, Lilongwe is experiencing uncontrolled and unplanned urban expansion that has led to the growth of informal settlements. Urbanisation leads to land use land cover (LULC) changes that negatively impact the quality of life and the environment. Lilongwe faces many challenges, including high levels of poverty, inequality, poorly built infrastructure, lack of access to safe sanitation and clean water, urban flooding, and poor waste disposal. Effective land use planning is important in mitigating future urbanisation's adverse effects. To prepare and plan for the inevitable future urban growth of the city, studies of historical land use land cover changes are essential in understanding the urbanisation trajectory of the city. This study used post classification change detection and the SLEUTH urban growth model to analyse land use land cover changes in Lilongwe from 2002 to 2022. Results revealed that Lilongwe’s urban growth is characterised by the expansion of built area coverage within and on the edges of already existing urban clusters. While urban growth is apparent in all parts of the city, it is concentrated in the northwest, southwest, and southeast.

Dynamics of ecosystem services (ESs) in response to land use land cover (LU/LC) changes in the lower Gangetic plain of India

This study was aimed at examining land cover changes for the last 35 years and its causative factors in Gilgel Abbay watershed by using GIS and remote sensing, survey and population data. The land use and cover changes study will help to apply the appropriate land use. The land cover/use status for the years 1973, 1986, 1995 and 2008 were examined using land sat images. The changes in different land cover units such as forest, wood and bush lands, grass, wetlands and water bodies, and farm and settlements were analyzed. Population change, tenure, poverty and lack of market and credit facilities in the watershed area were analyzed as causes of land cover changes. The results of the study have shown that during the last 35 years forest, grass lands, wetlands and lake areas were converted to farm and settlement areas. There was rapid increase of population with growth rates of 4.9% and 3.5% (1984-1994 and 1994-2007), respectively per annum which caused more land cover changes.

The pace of change in land use and cover in Ethiopia depends on three main factors that cause pressure on agriculture land: resettlement programmes, population growth and increasing agricultural investments. Gambella is one of the regions of Ethiopia that attracts large-scale agricultural investments that extensively drive land use and cover changes in the region. The aim of this study is to examine the rate, extent and distribution of various land use and cover changes in Gambella Regional State, Ethiopia, from 1987 to 2017. The analysis is mainly based on Landsat 5 and Sentinel 2A satellite images and fieldwork. Two Landsat Thematic Mapper and a Sentinel 2A image were used for determining the maximum likelihood of land use/cover classification. The results show that farmland decreased by 26 km2 from 1987 to 2000; however, during the last two decades, agricultural land area increased by 599 km2, mainly at the cost of tropical grasslands and forests. We found that areas cultivated by smallholder farmers increased by 9.17% from 1987 to 2000. However, small-scale farm activities decreased by 7% from 2000 to 2017. Areas cultivated by large-scale state farms totalled 202 km2 in 1987; but by 2000, this large-scale state farming had been completely abandoned by the state, and as a result, its land use has decreased to zero. Despite this, in 2017 large-scale farming increased to 746 km2. In addition, Gambella National Park, which is the nation's largest national park and ecosystem, was also largely affected by Land Use and Land Cover changes. The conversion of savannah/tropical grasslands to agricultural farmland has caused varied and extensive environmental degradation to the park. The Land Use and Land Cover changes in the Gambella region are discussed on the basis of underlying socioeconomic factors.

As one of the last agricultural frontiers of the humid tropics, Amazonia is the largest area of the world currently undergoing frontier settlement. Although the earliest intrusions of foreign populations into Amazonia date from pre-Hispanic times, the large-scale entrance of peasant colonists into the vast region is a recent phenomenon. Much of this movement represents the spontaneous migration of peoples, but governments in the region have also become increasingly interested in opening up and integrating Amazonia to national and international economies. These actions are frequently seen as potential solutions to a number of national problems, including the need to increase agricultural production, correct spatial imbalances in the distribution of population, exploit frontier lands for reasons of national security, and defuse potentially serious political problems resulting from the existing agrarian structure, landlessness, and unemployment. The upper basin of the Amazon in Ecuador, bordering on the eastern slopes of the Andes, is one such area of frontier settlement. Recent decades have witnessed the rapid conversion of these Amazonian forests to agricultural uses through a series of schemes bearing such labels as land development and colonization. Most forest intervention in the region has come at the hands of colonist farmers attempting to establish land claims along transport routes originally constructed to aid in petroleum exploration and exploitation. These are farmers who formerly have made a living in long-established farmlands and who, for various reasons (population pressures, pervasive poverty, maldistribution of farmland, lack of inputs for intensive cultivation, lack of nonagrarian livelihood opportunities, and generally inadequate rural development) have been increasingly squeezed out of their homelands. A marginal person by virtue of his low socioeconomic and political status, the farmer often perceives

Over the past two decades, Addis Ababa has witnessed a relentless transformation in its land use and land cover. Primarily driven by the conversion of agricultural land through extensive expropriation in the city’s expansion areas. The study explores the dynamic land use land cover changes and associated land expropriations from peri-urban farmers in the rapidly growing Addis Ababa, Ethiopia. The study utilized a time series of global land cover and land-use change datasets (GLAD) covering the years 2000–2020. Moreover, empirical data is gathered through a household survey conducted among 349 systematically selected expropriated farmers across four sub-cities of Addis Ababa. The findings underscore a profound shift in the city’s land use and land cover over the past two decades. The built-up area emerges as the predominant land cover, witnessing a substantial increase of 25.28% (13,150.30 ha) over the past two decades. Concurrently, agricultural land and vegetation cover decreased by 15.92% and 9.35%, respectively, indicating a significant outward expansion of the city. This expansive growth, driven by the city’s rapid development, has resulted in extensive land expropriations primarily affecting peri-urban farmers. The expropriations were mainly for housing, investment, industrial parks, and infrastructure development. Thus, we urge the city administration to carefully manage the horizontal expansion of built-up areas at the expense of the agricultural land and vegetation cover. Finally, we recommend holistic and sustainable development strategies, developed collaboratively with local communities and planners, to safeguard the long-term wellbeing of city residents.

Spatial analysis of land use and cover changes: Implications of green legacy initiative on climate action in Upper Awash Basin, Ethiopia

Unprecedented human-induced land cover changes happened in China after the Reform and Opening-up in 1978, matching with the era of Landsat satellite series. However, it is still unknown whether Landsat data can effectively support retrospective analysis of land cover changes in China over the past four decades. Here, for the first time, we conduct a systematic investigation on the availability of Landsat data in China, targeting its application for retrospective and continuous monitoring of land cover changes. The latter is significant to assess impact of land cover changes, and consequences of past land policy and management interventions. The total and valid observations (excluding clouds, cloud shadows, and terrain shadows) from Landsat 5/7/8 from 1984 to 2017 were quantified at pixel scale, based on the cloud computing platform Google Earth Engine (GEE). The results show higher intensity of Landsat observation in the northern part of China as compared to the southern part. The study provides an overall picture of Landsat observations suitable for satellite-based annual land cover monitoring over the entire country. We uncover that two sub-regions of China (i.e., Northeast China-Inner Mongolia-Northwest China, and North China Plain) have sufficient valid observations for retrospective analysis of land cover over 30 years (1987–2017) at an annual interval; whereas the Middle-Lower Yangtze Plain (MLYP) and Xinjiang (XJ) have sufficient observations for annual analyses for the periods 1989–2017 and 2004–2017, respectively. Retrospective analysis of land cover is possible only at a two-year time interval in South China (SC) for the years 1988–2017, Xinjiang (XJ) for the period 1992–2003, and the Tibetan Plateau (TP) during 2004–2017. For the latter geographic regions, land cover dynamics can be analyzed only at a three-year interval prior to 2004. Our retrospective analysis suggest that Landsat-based analysis of land cover dynamics at an annual interval for the whole country is not feasible; instead, national monitoring at two- or three-year intervals could be achievable. This study provides a preliminary assessment of data availability, targeting future continuous land cover monitoring in China; and the code is released to the public to facilitate similar data inventory in other regions of the world.

Aighewi, I.T.; Nosakhare, O.K., and Ishaque, A.B., 2013. Land use–land cover changes and sewage loading in the lower Eastern Shore watersheds and coastal bays of Maryland: Implications for surface water quality.Changes in land use and cover influence surface water quality and thus are a potential threat to water systems and coastal ecosystem health. The objectives of this study were to evaluate the influence of historical land use–land cover (LULC) changes and point-source sewage discharge on surface water quality of some lower Eastern Shore watersheds of Maryland. LANDSAT data for 1986–2006 was acquired and classified using Anderson level-1 classification system in ENVI 4.5, whereas LULC changes were detected in Arc-GIS 9.2 environment. Historical water monitoring and climatic data were obtained from Maryland Department of Environment–Chesapeake Bay Program, and National Oceanic and Atmospheric Administration, respectively. Nutrient loading data from wastewater treatment plants were obtained from Maryland Department of Environment and data analyzed using regression analysis and principal component analysis (PCA). The result shows that total phosphorous levels in the surface waters decreased significantly (p < 0.05) during the 20-year study period. However, using PCA, we determined that the declining P trend was attributable to the decreasing agricultural land use rather than the sewage discharge from wastewater treatment plants. The increase in urban land use and the resultant runoff to the water bodies may explain the declining trends in dissolved oxygen levels observed during the period, with serious implications for eutrophication. An empirical model developed for P in surface waters (r2 = 0.90) showed that the combination of point and nonpoint sources and land use/cover change factors are good predictors. The incorporation of quantitative LULC data component as well as point-source nutrient loading into existing models is highly recommended for a more holistic assessment of land-use influence on water systems in general.

To demonstrate potential future consequences of land cover and land use changes beyond those for physical climate and the carbon cycle, we present an analysis of large‐scale impacts of land cover and land use changes on atmospheric chemistry using the chemistry‐climate model EMAC (ECHAM5/MESSy Atmospheric Chemistry) constrained with present‐day and 2050 land cover, land use, and anthropogenic emissions scenarios. Future land use and land cover changes are expected to result in an increase in global annual soil NO emissions by ∼1.2 TgN yr−1 (9%), whereas isoprene emissions decrease by ∼50 TgC yr−1 (−12%). The analysis shows increases in simulated boundary layer ozone mixing ratios up to ∼9 ppbv and more than a doubling in hydroxyl radical concentrations over deforested areas in Africa. Small changes in global atmosphere‐biosphere fluxes of NOx and ozone point to compensating effects. Decreases in soil NO emissions in deforested regions are counteracted by a larger canopy release of NOx caused by reduced foliage uptake. Despite this decrease in foliage uptake, the ozone deposition flux does not decrease since surface layer mixing ratios increase because of a reduced oxidation of isoprene by ozone. Our study indicates that the simulated impact of land cover and land use changes on atmospheric chemistry depends on a consistent representation of emissions, deposition, and canopy interactions and their dependence on meteorological, hydrological, and biological drivers to account for these compensating effects. It results in negligible changes in the atmospheric oxidizing capacity and, consequently, in the lifetime of methane. Conversely, we expect a pronounced increase in oxidizing capacity as a consequence of anthropogenic emission increases.

Earth’s land cover has been extensively transformed over time due to both human activities and natural causes. Previous global studies have focused on developing spatial and temporal patterns of dominant human land-use activities (e.g., cropland, pastureland, urban land, wood harvest). Process-based modeling studies adopt different strategies to estimate the changes in land cover by using these land-use data sets in combination with a potential vegetation map, and subsequently use this information for impact assessments. However, due to unaccounted changes in land cover (resulting from both indirect anthropogenic and natural causes), heterogeneity in land-use/cover (LUC) conversions among grid cells, even for the same land use activity, and uncertainty associated with potential vegetation mapping and historical estimates of human land use result in land cover estimates that are substantially different compared to results acquired from remote sensing observations. Here, we present a method to implicitly account for the differences arising from these uncertainties in order to provide historical estimates of land cover that are consistent with satellite estimates for recent years. Due to uncertainty in historical agricultural land use, we use three widely accepted global estimates of cropland and pastureland in combination with common wood harvest and urban land data sets to generate three distinct estimates of historical land-cover change and underlying LUC conversions. Hence, these distinct historical reconstructions offer a wide range of plausible regional estimates of uncertainty and the extent to which different ecosystems have undergone changes. The annual land cover maps and LUC conversion maps are reported at 0.5°×0.5° resolution and describe the area of 28 landcover types and respective underlying land-use transitions. The reconstructed data sets are relevant for studies addressing the impact of land-cover change on biogeophysics, biogeochemistry, water cycle, and global climate.