Changes In Land Area Research Articles

Human-Dominated Land Use Change in a Phosphate Mining Area and Its Impact on the Water Environment

The Peace River is a critical water source in southwest Florida, United States. The watershed contains many phosphate mines that decrease water safety. Whether phosphate mining leads to a reduction in surface runoff and affects water quality in the Peace River Basin has been a highly controversial subject. Thus, the environmental impacts of phosphate mining in the Peace River were assessed. The Soil and Water Assessment Tool (SWAT) model is a widely used physical-mechanism-based distributed hydrological model that uses spatial distribution data, such as topography, soil, land use, and weather, to predict water, sediment, nutrient, pesticide, and fecal bacteria production. Based on a SWAT model, runoff, total nitrogen (TN) load, and total phosphorus (TP) load at the outlet of the Peace River Basin from 2001 to 2018 were investigated. The applicability of the four uncertainty methods in the hydrological simulation of the basin was assessed. The runoff at five stations in a specified mining area was simulated to analyze the impact of human-dominated land use changes caused by phosphate mining on the water environment. The results for the pre- and post-mining periods showed that the land use transfer in the study area experienced large fluctuations and that the land use change had a significant impact on the runoff (the outlet site decreased by 44.14%), indicating that phosphate mining has a significant effect on reducing runoff in the basin. An analysis of three scenarios (pre-mining [s1], post-mining [s2], and reclamation [s3]) showed that during s1–s2–s3, the change in mining land area is large (increased by 142.86%) and that TN and TP loads increased, indicating that human activities mainly affect the water environment through phosphate mining. This is mainly because a large amount of wastewater containing high concentrations of inorganic chemicals, which is produced in the process of phosphate mining and processing, overflows directly or from the sedimentation tank into the river. In summary, the simulation results showed that the changes in runoff and pollutants were attributed to phosphate rock mining. Therefore, strengthening the management of phosphate mining and adopting effective protection measures is of substantial significance for the effective protection of water resources. By analyzing the measured data, this study can help people understand more actual situations and further evaluate the impact of phosphate mining activities on the water environment. The simulation results can also be used to predict the future trend of runoff and water quality in the Peace River Basin and provide a decision-making basis for government management departments to issue water resource protection measures.

PRODUCTION POTENTIAL OF THE VEGETABLE SECTOR IN POLAND AND SELECTED EU COUNTRIES

The aim of the research was to assess the production potential of the vegetable sector, as a factor of competitiveness, in Poland and selected EU countries. The evaluation of vegetable production was based on a comparative analysis of the level and changes in land area devoted to crops, yields, the number of farms and the average area of crops on the farm, the species structure of crops, the level of basic vegetable yields, and the resources of the factors of vegetable farm production from the FADN system. The research has shown that Poland’s high and growing position in vegetable production results mainly from the high acreage of crops, their partially complementary structure, and above all from relatively low labour costs compared to other surveyed EU countries. On the other hand, the improvement of effectiveness is not supported by the large fragmentation of Polish farms, although an increase in the average area of cultivation per farm was observed in the examined period. The research shows that in most of the analysed countries there was still a large fragmentation of vegetable farms. The analysis of vegetable farm inputs (on the basis of FADN data) in selected countries also shows that in the analysed period, a decrease in production factor resources was observed in Poland, Italy and France.

Spatio-Temporal Heterogeneity of Urban Expansion and Population Growth in China.

Urbanization has become one of the hot issues of global sustainable development, and is mainly characterized by urban population growth and construction land expansion. However, the inharmonious development of urban expansion and population migration has brought serious challenges to urban planning and management. China is the largest developing country in the world, and the urbanization process has accelerated over the past decades. In this paper, decoupling analysis was used to demonstrate the spatio–temporal relationship between urban expansion and population growth in 321 prefecture–level cities in China, providing a reference basis for sustainable development. The results showed that China’s population, total GDP, and construction land area increased from 1990 to 2018. The rate of construction land expansion was larger in the eastern coastal and western regions than in the northeastern and central regions, but the population growth rate was not significantly different among these regions. According to the decoupling analysis, the relationships of population–GDP, construction land–GDP, and population–construction land were mainly weak decoupling, indicating that both the population growth and the construction land expansion lagged behind the economic development, and the population growth lagged behind construction land expansion. In addition, the results were analyzed based on China’s four economic regions. Population and construction land area changes in the northeastern provinces experienced a shift from weak decoupling to expansive negative decoupling, then presented a strong decoupling. The decoupling state of population–construction land in the west region was relatively stable. The relationship between population and construction land in the central regions was mainly weak decoupling, and some cities developed into strong decoupling. The relationship between population and construction land in the east region experienced a shift from strong decoupling to weak decoupling, then demonstrated expansive negative decoupling, mainly manifested in the Beijing–Tianjin–Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations. Therefore, the northeast region should take measures to promote regional population growth while reasonably controlling the expansion of construction land, the west region should focus on ecological protection and moderately attract population, the central region should control their population development and reasonably allocate land, and the east region should pay attention to and solve the citizenship problem of migrant workers in second–tier and third–tier cities when promoting new urbanization.

A Global Analysis of the Relationship Between Urbanization and Fatalities in Earthquake-Prone Areas

Urbanization can be a challenge and an opportunity for earthquake risk mitigation. However, little is known about the changes in exposure (for example, population and urban land) to earthquakes in the context of global urbanization, and their impacts on fatalities in earthquake-prone areas. We present a global analysis of the changes in population size and urban land area in earthquake-prone areas from 1990 to 2015, and their impacts on earthquake-related fatalities. We found that more than two thirds of population growth (or 70% of total population in 2015) and nearly three quarters of earthquake-related deaths (or 307,918 deaths) in global earthquake-prone areas occurred in developing countries with an urbanization ratio (percentage of urban population to total population) between 20 and 60%. Holding other factors constant, population size was significantly and positively associated with earthquake fatalities, while the area of urban land was negatively related. The results suggest that fatalities increase for areas where the urbanization ratio is low, but after a ratio between 40 and 50% occurs, earthquake fatalities decline. This finding suggests that the resistance of building and infrastructure is greater in countries with higher urbanization ratios and highlights the need for further investigation. Our quantitative analysis is extended into the future using Shared Socioeconomic Pathways to reveal that by 2050, more than 50% of the population increase in global earthquake-prone areas will take place in a few developing countries (Pakistan, India, Afghanistan, and Bangladesh) that are particularly vulnerable to earthquakes. To reduce earthquake-induced fatalities, enhanced resilience of buildings and urban infrastructure generally in these few countries should be a priority.

Spatial patterns of county-level arable land productive-capacity and its coordination with land-use intensity in mainland China

Evaluation of arable land ecosystem services capacity and arable land-use intensity (ALUI) is important for recognising key regional factors that impact arable land attributes changes, which is crucial for planning sustainable patterns of arable land use. The chronic lack of coordination between these two types of evaluation studies has made it hard to provide enough information for developing arable land-use management and control policies. Here, we generated a 1-km-grid map of arable land potential yield and county-level arable land productive-capacity. The impact of land-use and land-cover change on county-level total arable land productive-capacity during 1990–2010 had been estimated. Then we determined the aggregation–distribution characteristics of four indexes (i.e. average arable land potential yield, average ALUI, total arable land area and arable land productive-capacity reserves) at the county-level by the k-means algorithm to assess the regional coordination between arable land productive-capacity protection and arable land use. The results show that during 1990–2010, land-use change led to arable land productive-capacity decreases in 2007 of China’s 2733 counties (nearly 73.5% of the total counties’ count). Most of these counties are in central and southern China, and their corresponding arable land productive-capacity decrement rates are generally < 6.15%. Counties with decrement rates > 6.15% are mainly in the Yangtze and Pearl River delta regions. The geographical detector shows that county-level arable land-area change is a primary factor that drives county-level arable land productive-capacity increase. Its determinant power can be quantified as 74.154%. In contrast, its determinant power to county-level arable land productive-capacity decrease is only 38.542%, which demonstrates that occupy high-capacity arable land and supplement low-capacity arable land have a greater role in causing reduction of county arable land productive-capacity. Total arable land productive-capacity and use intensity show only slight determinant power to county-level arable land productive-capacity decrease. It indicates that insufficient attention has been paid to the protection of arable land productive-capacity and the farmers’ willingness in the implementation of China requisition-compensation balance policy. The aggregation–distribution characteristics show that arable land productive-capacity protection is in coordination with arable land use for most of the provinces in China. Arable land with high or medium potential yield tends to be used at high or medium intensity. A lack of coordination is most evident in the insufficient ALUI, particularly in seven of the thirteen major grain-producing provinces. Other evidence of weak coordination is in the low potential yield versus high farming conditions and willingness, where unsuited planting modes should be prevented. Lastly, challenges for exploring sustainable arable land use path have been discussed. This study is greatly instructive for recognising interrelations between natural conditions and arable land-use patterns and for exploring shortcomings that impede regionally sustainable arable land use.

Changes in Cultivated Land Area and Associated Soil and SOC Losses in Northeastern China: The Role of Land Use Policies.

Land use policy is the driving factor influencing land use; however, little research has been conducted to identify the role of agricultural policy in influencing land cultivation and associated soil and soil organic carbon (SOC) losses. The aims of this study were to explore temporal changes in cultivated land, soil erosion, and SOC loss and to identify the role of land use policy. The present study was conducted using the revised universal soil loss equation by integrating remote sensing images from 1980, 1990, 2000, and 2017. The study found that cultivated land areas increased from 275.11 thousand km2 in 1980, to 300.03 thousand km2 in 2000, and to 344.16 thousand km2 in 2010, and then decreased by 326.94 thousand km2. The mean soil loss rates changed from 590.66 t·km−2·yr−1 in 1980 to 634.25 t·km−2·yr−1 in 2010, and then decreased to 495.66 t·km−2·yr−1 in 2017. Soil loss rate increased with increasing slope gradient. The changes in SOC loss rates demonstrated the same pattern as that of soil loss, with the largest loss rate of 728.27 kg·km−2·yr−1. These changes can be explained by changed land use policy and population growth. In future land use management, reasonable implementation of soil conservation measures should be undertaken to reduce soil and SOC losses in the black soil region of northeastern China.

Climate change impacts on water security elements of Kafr El-Sheikh governorate, Egypt

Egypt faces great challenges to manage its limited freshwater resources. Shortage in freshwater, due to expected stresses of climatic changes and upper Nile projects, will have major impacts on Egypt's water and food security. About 85% of the annual total freshwater resource is consumed by agriculture. The objective of this work is to assess the future water security situation of Kafr El-Sheikh governorate, Nile Delta, Egypt, under climate change and urbanization stresses, compared to the current situation. Main investigated water security elements for this study were the irrigation water requirements and agricultural land areas. Two different reference evapotranspiration equations were used to calculate the future irrigation water requirements under three different Representative Concentration Pathways (RCP) (2.6, 4.5 and 8.5 scenarios) for the period 2010–2100, based on the intergovernmental panel on climate change’s 5th assessment report. Remote sensing and Geographical Information System (GIS) were used to generate a land use classification map, which was used to estimate the losses in each land use category of the study area under 0.5 and 1.0 m relative sea level rise (SLR) estimates. Combined scenarios of future changes in irrigation water consumption and agricultural land area were analysed. The results show that the future water security situation of the governorate is highly sensitive to projected climatic changes. Moreover, most future scenarios revealed that the agricultural land area would decrease, which will cause serious food security problems. The maximum decrease by about 55.9% of the agricultural land area for year 2095 compared to year 2016 is estimated, due to the current annual decreasing rate of 0.4% and 1.0 m SLR, whatever the applied RCP scenario. While the maximum increase in the required irrigation water would be about 6% due to the RCP85 scenario, assuming no change in the irrigation land area, with a mixing ratio of 1.34 (freshwater): 1 (drainage water) which would affect the crop yield productivity. A regular assessment of water security elements for each of the Egyptian governorates should be managed and an urgent integrated plan for food security to adapt with the future climate change impacts is essential.

Effects of Urbanization on Solid Waste Pollution in the Current Urban Suburbs of Ha Noi: The Case of Hoai Duc District

In recent years, solid waste pollution has been a burden on sustainable development in Vietnam. The suburban districts in major cities, in particular, have all witnessed a high rate of urbanization and a rapidly increasing amount of solid waste. Focusing on the case of unsustainably managed solid waste in Hoai Duc district (2016-2020), five research hypotheses, including factors affecting the increase of solid waste in Hoai Duc, are proposed, i.e.: Industrialization (based on the change of agricultural land area), population growth, urbanization (manifested by changes in urban land area), socio-economic policies, and educational qualification and public awareness of residents as well. It can be seen that population growth is just an indirect contributor to the situation, meanwhile, the sole cause of large daily plastic waste is none other than the burgeoning population attracted by urbanization. Therefore, the majority of attention and resources should be placed on strengthening policies that can keep urbanization under control, to ensure sustainable environmental development in addition to economic development.

Identification of Environmental Change in Bukit Kerang, Aceh Tamiang Regency Using Landsat Satellite Imagery

Changes in land cover and temperature in Bukit Kerang have been investigated using Landsat satellite images. We used Landsat 5 TM Landsat satellite imagery in 1988, Landsat 7 ETM in 2000, and Landsat 8 OLI in 2020. The ENVI 4.7 and ArcGIS 10.3 software was used to perform radiometric corrections, image cropping, image classification, image reclassification, calculating area, and layouts. Changes in land cover and land area in 1988, 2000, and 2020 affected the surface temperature conditions in those three years. In 1988, the dominant land area of forest cover was 5,926.44 ha (1 ha = 104 m2), with the dominant temperature distribution of 17.2° C. In 2000, there was an increase in settlements by 25.56 ha and rice field area, which caused an increase in the temperature distribution of 19.7 – 25.4° C. In 2020, forest type land cover changes into plantations, fields, and settlements decreased by 3,731.91 ha, increasing temperature distribution of 20.6 – 21.8° C. Thus, there is a strong relationship between changes in land cover and change in surface temperature in Bukit Kerang area.

Impact of Agricultural Land Changes on Farmers’ Income in Cirasea Watershed, Bandung Regency, West Java

Changes from agricultural land to non-agricultural land are continuously occurring, especially in areas adjacent to cities. Land changes from agricultural to non-agricultural land will eliminate crops’ hydrological function, impacting rivers, including the Cirasea River. Besides, changes in agricultural land have an impact on the resulting agricultural productivity and income. This study’s main objective is to determine land area changes, productivity, and farmers’ income in 2011 - 2018 in the Cirasea watershed. A literature study was applied to this study. Secondary data were obtained from the Central Bureau of Statistics of Ciparay, Ibun, Kertasari, Majalaya, Pacet, and Paseh Districts, Bandung Regency in Cirasea River Upstream. The study results showed an increase in land area, productivity, and agricultural income for vegetables (75%, 50%, and 68%, respectively) and rice field (16%, 0.32%, and 0.32%). In addition, there was a decrease in land area followed by a decrease in agricultural productivity and income for fruit commodities (-88%, -35%, -33%) and plantations (-97%, -1%, -1%). For eight years, farmers have relied on their income from vegetable commodities in Cirasea Watershed.

Land Concentration Processes: Polish Case Study in the Light of Selected EU Countries

Purpose: The purpose of the article was an attempt to create a new synthetic measurement of farm area changes and to identify farmers’ attitiudes and knowledge in scope of land concentration processes. Design/Methodology/Approach: The Aggregated ratio of Farm Area Changes were introduced as a proposal for a new measurement of farm structures. Moreover 200 agricultural farms were investigated using survey on the area of selected polish region. Findings: The work focuses on valuable universal measurement for international comparisons in the range of land turnover. Tha reached informations and knowledge during surveying on the farms site conformed high level of consciousness within land market, plans for the futher and reasons and motives of land concetration. The farmers – active playesr on land market – see problems that the institutional environment cannot recognize. Practical Implications: Possibility of implementation of new universal measurement for international comparisions with coexistence with available statistical databases. Practical notices and remarks of experienced farmers for legal regulation proposals to avoid further land concentration processes excluded by European Green Deal rules. Originality/value: The value of the research is innovative research method – ARFACH – Aggregated Ratio of Land Area Changes. Moreover unique research based on survey results on farm site allows to create new legal regulations to limit land concentration processes in European agriculture.

Projections of Global Delta Land Loss From Sea‐Level Rise in the 21st Century

AbstractRiver deltas will likely experience significant land loss because of relative sea‐level rise (RSLR), but predictions have not been tested against observations. Here, we use global data of RSLR and river sediment supply to build a model of delta response to RSLR for 6,402 deltas, representing 86% of global delta land. We validate this model against delta land area change observations from 1985–2015, and project future land area change for IPCC RSLR scenarios. For 2100, we find widely ranging delta scenarios, from +94 ± 125 (2 s.d.) km2 yr−1 for representative concentration pathway (RCP) 2.6 to −1,026 ± 281 km2 yr−1 for RCP8.5. River dams, subsidence, and sea‐level rise have had a comparable influence on reduced delta growth over the past decades, but if we follow RCP8.5 to 2100, more than 85% of delta land loss will be caused by climate‐change driven sea‐level rise, resulting in a loss of ∼5% of global delta land.

Using Swarm to Detect Total Water Storage Changes in 26 Global Basins (Taking the Amazon Basin, Volga Basin and Zambezi Basin as Examples)

The Gravity Recovery and Climate Experiment (GRACE) satellite provides time-varying gravity field models that can detect total water storage change (TWSC) from April 2002 to June 2017, and its second-generation satellite, GRACE Follow-On (GRACE-FO), provides models from June 2018, so there is a one year gap. Swarm satellites are equipped with Global Positioning System (GPS) receivers, which can be used to recover the Earth’s time-varying gravitational field. Swarm’s time-varying gravitational field models (from December 2013 to June 2018) were solved by the International Combination Service for Time-variable Gravity Field Solutions (COST-G) and the Astronomical Institute of the Czech Academy of Sciences (ASI). On a timely scale, Swarm has the potential to fill the gap between the two generations of GRACE satellites. In this paper, using 26 global watersheds as the study area, first, we explored the optimal data processing strategy for Swarm and then obtained the Swarm-TWSC of each watershed based on the optimal results. Second, we evaluated Swarm’s accuracy in detecting regional water storage variations, analyzed the reasons for its superior and inferior performance in different regions, and systematically explored its potential in detecting terrestrial water storage changes in land areas. Finally, we constructed the time series of terrestrial water storage changes from 2002 to 2019 by combining GRACE, Swarm, and GRACE-FO for the Amazon, Volga, and Zambezi Basins. The results show that the optimal data processing strategy of Swarm is different from that of GRACE. The optimal results of Swarm-TWSC were explored in 26 watersheds worldwide; its accuracy is related to the area size, runoff volume, total annual mass change, and instantaneous mass change of the watershed itself, among which the latter is the main factor affecting Swarm-TWSC. Knowledge of the Swarm-TWSC of 26 basins constructed in this paper is important to study long-term water storage changes in basins.

A detailed reconstruction of changes in the factors and parameters of soil erosion over the past 250 years in the forest zone of European Russia (Moscow region)

Accelerated soil erosion is a major threat to soil, and there are great variations in the rate of soil erosion over time due to natural and human-induced factors. The temperate forest zone of Russia is characterized by complex stages of land-use history (i.e. active urbanization, agricultural development, land abandonment, etc.). We have for the first time estimated the rates of soil erosion by the WaTEM/SEDEM model (rainfall erosion) and by a regional model (snowmelt erosion) over the past 250 years (from 1780 to 2019) for a 100-km2 study site in the Moscow region of Russia. The calculations were made on the basis of a detailed historical reconstruction of the following factors: the location of the arable land, crop rotation, the rain erosivity factor, and the maximum snow water equivalent. The area of arable land has decreased more than 3.5-fold over the past 250 years. At the end of the 20th century, the rates of gross erosion had declined more than 5.5-fold (from 28 × 103 to 5 × 103 tˑha−1ˑyr−1) in comparison with the end of the 18th century. Changes in the boundaries of arable land and also the relief features had led to a significant intra-slope accumulation of sediments. As a result of sediment redeposition within the arable land, the variation in net soil erosion was significantly lower than the variation in gross soil erosion. The changes in arable land area and in crop composition are the factors that have to the greatest extent determined the changes in soil erosion in this territory.

Multi-Decadal Deltaic Land-Surface Changes: Gauging the Vulnerability of a Selection of Mediterranean and Black Sea River Deltas

Areal changes over delta surfaces determined by land and water ratios are a promising tool for identifying spatial and temporal changes in deltas that may reveal subsidence and shoreline erosion. Such changes can also provide the basis for more detailed studies on variations in land-cover and vegetation. Changes in land and water areas over a 35-year period (1984–2019) were determined for a selection of ten river deltas in the Mediterranean (Nile, Rhône, Po, Ebro, Moulouya, Ceyhan-Seyhan, Medjerdja, Ombrone, Arno) and the Black Sea (Danube), with a particular focus on aspects of subsidence and shoreline erosion. With the exception of the Ombrone, Arno, and Moulouya, and to lesser extent the Medjerdja, where notable changes dominate in the coastal zone and are tantamount to net erosion, the spatial pattern is largely dominated by delta-plain changes characterized by increasing areas of water. The pattern reflects a mix of shoreline erosion, land-use and land-cover changes, such as the ecological restoration of wetlands, but also increasing subsidence in these deltas, all of which have been exposed to a declining fluvial sediment supply due to human influence. The use of data on land-water ratios needs to be complemented by more detailed studies devoted to each delta in order to clearly disentangle changes related to land-use, vegetation, and subsidence. It is also important to determine how wetlands are interpreted in such ratios, as these important ecological elements are sensitive to ratio variations. It would also be interesting in future studies to examine how these variations play out over time, notably in deltas where changes have been significant over the period 1984–2019.

Evaluation of shoreline change using multitemporal satellite images

Coastal areas are vulnerable to change because, in this region, many human activities and natural influences change. These activities can result in changes in the existing coastline. Moreover, the city of Surabaya has a reasonably long coastline. This study calculated the speed of shoreline change using remote sensing technology of SPOT 6 and SPOT 7 high- resolution satellite imagery from 2015 to 2019. Calculation of shoreline change speed is assisted by the application of the Digital Shoreline Analysis System (DSAS) using several methods, namely Shoreline Change Envelope (SCE), Net Shoreline Movement (NSM), End Point Rate (EPR), and Linear Regression Rate (LRR). Based on data processing and analysis, the longest coastline of Surabaya City was found in 2015 with a length of 69.605 km, and the shortest coastline was in 2019 with a length of 65.759 km. The maximum speed of Surabaya shoreline changes can be identified by using the SCE method (956.590 m), the NSM method (+584.722 m), the EPR (+148.725 m per year), and the LRR (+154.386 m per year). Also, an analysis of land area changes during the 20152019 period resulted in the Kalisari Village experiencing the most significant accretion of 358073.62 m2, while in Keputih Village abrasion of 30189.72 m2.

Land conversion and availability of agricultural land in 2035 in Puncak Area Bogor Regency

Land conversion is the result of a complex interaction between physical, social, and economic activities in land use as human activities in natural resource management. Currently, the land conversion phenomenon is a common sight that we often encounter at any time. As happened in the Puncak area of Bogor Regency, land conversion, the increasing demand for land, has led to increasing land conversion. This study aims to (1) identify land conversion in Bogor Regency in 2005-2015, (2) predict agricultural land conversion in 2035 based on land use trends in Puncak District, Bogor Regency. The analytical methods used are remote sensing techniques, spatial analysis, and making land-use scenarios with GIS and ANN analysis. The results showed that land conversion in Puncak Subdistrict, Bogor Regency during 2005-2019 caused the area of agricultural land to decrease by an average of 82.59 hectares every year due to conversion to developed land and open land. From the prediction of changes in agricultural land area in 2035, it shows a decrease in rice fields and fields on average 60.90 hectares every year. However, the plantation area has increased by an average of 24.35 hectares every year due to the conversion from forest and shrubs.

Land management in the Oryol region agriculture

This paper discusses the current problems of land management in the Oryol region agriculture based on the study of the economic characteristics of land as a real estate object. Based on statistical data, the analysis of the land potential of the Oryol region was carried out, the current state and dynamics of changes in agricultural land areas were studied. The total area of agricultural land plots that meets the requirements of the country’s legislation regarding their classification as particularly valuable land for agricultural production, the use of which is restricted for other purposes, is determined. The differential nature of the value of the cadastral value of agricultural land in the Oryol region is studied, the specifics and functional purpose of the cadastral value as an economic category of land plots are determined. That is why effective land management of agricultural enterprises at the regional level is an urgent problem that requires timely solutions based on the integration of organizational and economic aspects of management actions. All this indicates that it is necessary to continue research related to both forms of land ownership and improvement of economic relations in terms of the use of agricultural land.

Global-scale changes in the area of atoll islands during the 21st century

The long-term persistence of atoll islands is under threat due to continued sea level rise driven by anthropogenic climate change. One widely discussed potential impact of sea level rise is the widespread, chronic erosion of atoll islands. Despite concerns of erosion driven by sea level rise, no published evidence exists of pervasive erosion of atoll islands at a global scale. Existing studies of atoll island change have been based on small, temporally sparse samples of islands on a limited number of atolls. As a result, the global response of atoll islands coincident with sea level rise remains uncertain. Using rich collections of Landsat imagery, this study analyses changes in land area on 221 atolls in the Indian and Pacific Oceans. Results show that, between 2000 and 2017, the total land area on these atolls has increased by 61.74 km2 (6.1 %) from 1007.60 km2 to 1069.35 km2. Most of the change in land area resulted from island building within the Maldives and on atolls in the South China Sea. Since 2000, the Maldives have added 37.50 km2 of land area, while 16.57 km2 of new islands have appeared within the South China Seas Spratly and Paracel chains. Understanding the extent of land area change at the global scale improves insights into the variation in responses, and how the manipulation of land is shaping the potential habitability trajectory for some atoll communities. Results highlight the anthropogenic imprint on the size of atoll islands, thereby providing a better understanding of variations in the future trajectories of human settlement and adaptation within atoll settings.

Significance of drones in monitoring of agricultural lands of Uzbekistan

Software of Geographic Information Systems (GIS) has been widely used for land evaluation and detection of changes in land area. Using GIS it is possible now to combine different environmental, social, economic data, which in turn leads to lower costs and allows collecting and processing a variety of data with the exact calculation of the required results necessary for land use. Therefore, research has been focused on remotely controlled devices. The research has been conducted to simplify the land record keeping (land inventory) system and to improve land monitoring methods using remote-controlled devices. As a result, economic efficiency and productivity have been increased.