Main Land Use Research Articles

Study of Identification and Simulation of Ecological Zoning through Integration of Landscape Ecological Risk and Ecosystem Service Value

Rapid urbanization has caused numerous environmental issues, constraining regional sustainable development. Constructing ecological zoning is conducive to scientific ecological protection and management. Taking the Anhui section of the water and soil conservation functional area in the Dabie Mountains of China as an example, this study calculated the ecosystem service value (ESV) and landscape ecological risk (LER) from 2000 to 2020 using the value equivalent method and the landscape ecological risk index, respectively, and analyzed their spatio-temporal evolution characteristics. Considering the vulnerability of ecosystem and its service functions, four types of ecological zones were constructed based on ESV and LER, and the PLUS model was used to predict the ecological zones in 2030 and 2040. The results indicated that: (1) The main land use type in the study area was forestland, accounting for 75% of the total area. During the study period, the most significant increase in land use was observed in cropland, with an increase of 268.03 km2, while the most significant decrease was in grassland, with a total reduction of 645.26 km2. (2) Low and medium-low ecological risk areas were the main LER types in the study area, accounting for approximately 85% of the total area. The LER gradually shifted towards medium-high risk areas, showing a slight upward trend. The ESV showed a continuous increasing trend, with a total increase of 2.34 billion yuan. The ESV was dominated by medium ESV, and the area was expanding. (3) The ecological zoning was primarily dominated by ecological conservation areas, with a rapid expansion of 21.83%. In contrast, the ecological protection areas had the smallest area and the largest decrease, reaching 48.55%. It was expected that the spatial distribution of ecological zones will remain similar to that of 2020 from 2030 to 2040, with the largest decrease in the area of ecological conservation zones. The accelerating urbanization process may be the main reason for this phenomenon.

An Assessment of Spatio-temporal Land Use/Land Cover Dynamics Using Landsat Time Series Data (2008-2022) in Kuliyapitiya West Divisional Secretariat Division in Kurunagala District, Sri Lanka

The main aim of the study is to detect the changes of land use land cover (LULC) in Kuliyapitiya West Divisional Secretariat division during 2008-2022. Following the download of Landsat images in the study area, several procedures were taken to pre-process the images. This included performing radiometric and geometric corrections to eliminate undesired sensor data and atmospheric noise. The Maximum Likelihood Classification (MLC) was used as the main technique of image post-processing to derive land use maps for the target years. To evaluate the accuracy of outputs 525 ground control points were verified using the Google Earth Pro engine. The classification accuracy of the study was 86% for 2008, 79 % in 2015, and 80 % in 2022. The results showed that over the past 15 years, settlements and built-up areas increased from 20.84% to 28.14% and 0.33% to 2.71%, respectively, whereas coconut lands decreased from 58.3% to 48.6%. The settlement, which showed an increase of land area of 11.9 km2 throughout the period, was identified as the main land use gainer while coconut was the main land use that lost 15.9 km2 of its land area over the past fifteen years. The built-up area showed a 3.96 km2 overall gain during the period due to urbanization and the expansion of the industrial, educational, and service sectors in the study area. The other four land use classes have not undergone any significant changes throughout the relevant time. The study highlights the importance of combining accuracy evaluation and image classification algorithms to gain a more comprehensive understanding of the LULC changes. Hence, our findings could assist decision-makers in land use planning to efficiently guide the sustainable land management.

Floods and Land Use Land Cover Changes in the Kalu River Basin: A Call to Action


 
 
 Floods are one of the most common natural disasters worldwide. Apart from rainfall, Land Use Land Cover (LULC) changes too are a main contributory factor for floods. This study attempted to understand the link between floods and LULC changes in Kalu river basin, which is the second largest river basin and an area that experiences recurrent floods in Sri Lanka. We studied peak water levels, number of flood events, changes in land use types and impacts in rapidly urbanizing two districts, Rathnapura (upper basin) and Kalutara (lower basin) during 2001-2020. The satellite images (LANDSAT) were obtained for 2001, 2009, 2015 and 2020 and land use classification was done using ArcGIS and Remote Sensing Tools. Main land use types and their transformations were investigated and ground-truthing was carried out. Accordingly, the main types of land uses identified were Natural Vegetation and forests (NV), Settlements (ST- housing and industrial lands), Cultivated Lands (CL), Water Bodies (WB) and Bare Lands (BL). The results indicated that the most drastic change was found in the natural areas (NV) and they have diminished while the lands with anthropogenic impacts (ST, CL and BL) have increased across years. The NV had occupied the highest land area in 2001 (42.4%) and has reduced by 14.2% by 2020. The ST and CL have increased by 8.6 % and 5.2% respectively. The monthly rainfall of Rathnapura and Kalutara (Source: Department of Meteorology, Sri Lanka) has increased with time, which is a main reason for the increasing peak water levels of these areas (Source: Department of Irrigation, Sri Lanka). However, a significant correlation also exists between the change of the settlement area with the peak river water levels in the lower basin (p=0.03, R2=99%; regression analysis). Rathnapura has experienced 3 major floods (floods above the high water alert level) from 2001-2020, while 16 major floods have occurred in Kalutara. During the major flood in 2017, the number of child deaths in Rathnapura was 14 while in Kalutara it was 24. Accordingly, the LULC changes of the whole basin along with rainfall seem to influence on the severity of floods in Kalutara more, as it is located in the lowest elevation level. When natural lands are transformed to anthropogenic- impacted areas with disturbances to the water cycle, increased impervious surfaces, reduced water storage capacities and loss of natural drainage, the flood risk tends to increase. Proactive approaches including proper land use planning and rainwater storage are urgently needed as the climate change too would trigger more floods. Thus, the flood mitigatory actions, especially, in the lower river basin should be a priority to ensure resilience and sustainability.
 Keywords: Kalu river basin, Land Use Land Cover (LULC) changes, Floods
 
 

Grazing led to an increase in the root: shoot ratio and a shallow root system in an alpine meadow of the Tibetan plateau

Grazing is a main land use of natural grasslands in the world, which has both positive and negative impact on plant community structure and ecosystem functioning. However, the effects of long-term grazing management on the plant–soil system, in particular above- and belowground community characteristics, are still not well understood in alpine meadow community. In this study, we investigated the vegetation, roots, and soil properties under three management types (16 years of fencing since 2004-2020, moderate grazing and heavy grazing managements) in an alpine meadow on the Tibetan Plateau. The results showed that, compared with moderate grazing meadows, long-term fencing increased plant community cover, above- and belowground biomass, proportion of grass and litter but reduced forbs and soil bulk density, which caused the increases in soil organic carbon, total nitrogen and water content and the decreases in soil pH. However, heavy grazing led to opposite changes in proportion of grass, community biomass and soil physicochemical properties. The maximum of species richness and plant density appeared in moderate grazing meadows, supporting the intermediate disturbance hypothesis, and it can maintain above- and belowground biomass and soil physicochemical properties at medium level. Grazing increased the root: shoot ratio and caused root system shallow, which is consistent with the optimal partitioning hypothesis. Overall, our study suggested that moderate grazing is a more reasonable grazing management for sustainable development in alpine meadows of Tibetan Plateau, fencing could be an effective management strategy for vegetation restoration as well as for nutrient sequestration in degraded grasslands, but long-term fencing dose not benefit for biodiversity maintenance.

[Effects of Land Use Structure and Spatial Pattern at Different Temporal and Spatial Scales on Water Quality in Suzhou Creek].

Relationships between land use and water quality of rivers and lakes vary spatially and temporally. These variations were analyzed using spatial analysis and mathematical statistical methods for the Suzhou Creek in Shanghai. Based on the data of water quality and land use in 2001， 2005， 2010， 2015， and 2020， five spatial scales （200， 500， 1 000， 2 000， and 5 000 m reach buffer） of the landscape pattern were extracted using correlation and redundancy analysis to explore the impact of land use composition and spatial pattern on water quality at different spatial and temporal scales. The results showed that： ① the water quality of Suzhou Creek has gradually improved in the past 20 years； other indicators were between Class II to Class IV in 2020 except TN， and TN was the main pollutant. ② The main land use type of the buffer zone was construction land， and the proportion of greenland and woodland showed a small growth trend. ③ The water quality was closely related to landscape pattern， showing temporal and spatial scale effects. On the time scale， indicators such as construction land， agricultural land， landscape dominance， aggregation， and diversity had significant correlations with various water quality parameters， and there was an inverse correlation in 2010 compared with that in other years for NH4+-N， TP， and TN. The landscape pattern in 2001 had the greatest explanation for water quality， with an explanation rate of 93.65%. The impact of greenland and woodland on water quality has begun to emerge in the past 10 years. ④ On the spatial scale， there were significant correlations between greenland and woodland， patch number， landscape shape index， diversity index， and water quality. There was a strong positive regulatory effect of greenland and woodland on NH4+-N， TP， and TN at the scale of 2 000 m. The patch number and landscape shape index had relatively strong regulatory effects on water quality on a larger spatial scale， whereas the Shannon diversity index had a better positive regulatory effect on water quality on a small scale. The landscape pattern within a buffer of 2 000 m had the highest interpretation degree for all factors， with an explanation rate of 68.47%. The study showed that rationally planning the proportion of greenland and woodland within the 2 000 m buffer zone and optimizing its landscape configuration is an important measure to purify the surface water quality of Suzhou Creek.

Effects of tillage microrelief units on splash erosion: A case study from the Loess Plateau, in China

A tillage microrelief unit is the smallest spatially discontinuous area unit of tillage microrelief. Understanding the impact of tillage microrelief units on splash erosion is essential for selecting suitable tillage measures and employing soil and water conservation practices. The objective of this study was to investigate the characteristics and mechanisms of splash erosion under different tillage microrelief units in various directions and distances using the rainfall simulation experiment in the soil landscape of the Loess Plateau region in China, characterized primarily by sloping farmland as the main land use type. Three typical microrelief units, namely, artificial digging (AD), contour tillage (CT), and straight slope conditions (SSC) were designed at 0°, 3°, 5°, 10°, 15°, and 20° slopes. Tillage microrelief units with high surface roughness produced more splash erosion than flat lands. Further, the highest surface roughness increased the total splash amount by 102% relative to flat lands. The tillage microrelief unit itself was elevated with a certain slope, which increased the downslope splash of CT, SSC, and AD by 121%, 173%, and 11%, respectively. Different surface roughness values and slopes under different microrelief units were used to determine the amount of splash erosion. The results showed that the total splash amount responded significantly (P < 0.01) to the interaction between surface roughness and slope, and the sensitivity to roughness was higher than that to slope. According to the single-factor analysis, the surface roughness of all slopes significantly influenced the amount of splash erosion. Furthermore, the sensitivity of the tillage microrelief unit to the slope decreased because of the high slope under high surface roughness. Overall, the results of this study showed that in different tillage microrelief units of slopes in the Loess Plateau, SSC and CT significantly increased the outward splash erosion in this area, while AD significantly decreased the outward splash erosion. Moreover, slope did not have a considerable influence.

Consideration of the ecological factor during the cadastral assessment of the land of industrial enterprises

In 2022, a new state cadastral assessment took place in the Russian Federation, which does not determine the details of including a sanitary protection zone and assessing its cost to adjust the total cost of plots. The purpose of this study is to justify a return to the normative establishment of tax rates, taking into account changes in the state policy of regulating land and property relations. The purpose of the study was achieved by performing two tasks: analysing the share of the area of the sanitary protection zone, which should be taken into account when assessing the main land use of the enterprise, and determining the cost of this part of the sanitary protection zone. To solve the problems, standards and theoretical works are analysed, as well as the actual practice of using sanitary protection zones with regulatory requirements is compared. The result of the study is the possibility to use aggregated methods to calculate additional adjustments for industrial sites and territories with a sanitary protection zone, using the norms of green spaces and the costs of creation. These results can serve as a basis for the development of effective measures and regulations in the field of taxation of land and property relations.

Assessment of Physico-Chemical and Microbiological Parameters of Mthatha River in Eastern Cape, South Africa

Mthatha River is the main source of water for the fast-growing population of Mthatha communities and its surrounding. Human resident settlements, livestock grazing and watering, subsistence farming and commercial activities are the main water and land use activities in the catchment. Using the environmental forensic method, this study was carried out to assess water quality in Mthatha River and its selected tributaries for different uses (drinking and domestic use) and identify potential pollution sources. Seven sampling points were purposively selected for water quality testing along Mthatha River and the tributaries. Data was collected during wet and dry seasons of the year 2021. Microbiological and physico-chemical parameters were measured in this study. Microbiological samples (i.e., Total coliform and E. coli) were analysed in the laboratory within 24 h. Physico-chemical parameters (Dissolved Oxygen, water temperature, pH, Electrical Conductivity, Turbidity, Total Dissolved Solids and Nitrate) were measured in-situ. Multivariate statistical analysis, one-way analysis of variance (ANOVA), and Pearson’s correlation analysis were employed to analyse the data using SPSS version 22, Primer version 7 and MS Excel 2013.The pH, turbidity and nitrate were found to be higher during wet season than dry season. Extremely high microbiological indicators (E. coli and total coliform counts) were recorded during both seasons and exceeding the WHO and DWAF permissible limits. The study also found that agricultural activities in the upper reaches of the river and a combination of refuse dumping and sewage pollution in the mid-stream section are the main causes of changes in the water quality of the Mthatha River and its tributaries. An assessment and monitoring of the river water quality is necessary for the Mthatha community and to communicate information on water quality for sustainable watershed management practices.

Ecosystem sensitivity and landscape vulnerability of debris flow waste-shoal land under development and utilization changes

Debris flow waste-shoal land (DFWSL) is a new type of ecosystem in ecologically fragile areas of debris flows that is extremely sensitive to natural and anthropogenic disturbances. Existing studies have focused on the availability and utilization of DFWSL and impact analysis of DFWSL use with external environmental changes but have neglected to evaluate the vulnerability and sensitivity of the DFWSL system itself. To gain a more in-depth understanding of the sensitivity and vulnerability of the DFWSL system and the spatial relationship between them. In this study, a comprehensive and general methodology was developed to quantitatively illustrate the spatiotemporal changes of sensitivity and vulnerability of DFWSL and explore the spatially heterogeneous relationships between these relations and several socio-ecological drivers, integrating land transfer matrix, global Moran’s I and local Moran’s I, geographical detector, and multi-scale geographically weighted regression (MGWR) methods. Results show that the main land use types in the DFWSL, from 2014 to 2022, were cultivated and construction land. During that period, the area of cultivated land and water area decreased by 24.3% and 49.36%, respectively, while the area of forest land and construction land increased by 42.29% and 31.71%, respectively. Overall system sensitivity decreased during this period. The severe sensitive (Mid-High and High) area gradually decreased to the periphery areas and river basin outflows. The mild sensitive area increased (81% in 2014, 83% in 2018, and 90% in 2020) and was mainly located in the central area, mainly affected by elevation, rainfall, slope, and NDVImax. Landscape vulnerability (fragmentation) was mainly present in the central area, which was dominated by human activity (cultivated and construction land). The distributions of landscape vulnerability and sensitivity displayed a non-correspondence spatial correlation. This study improved our understanding of the spatial distribution characteristics of vulnerability and sensitivity of DFWSL and provided a basis for devising solutions to problems associated with disaster reduction and development.

Land Use Change and Landscape Ecological Risk Assessment Based on Terrain Gradients in Yuanmou Basin

Investigating the distribution characteristics of landscape ecological risk (LER) on terrain gradients is of great significance for optimizing the landscape pattern of ecologically vulnerable areas in mountainous regions and maintaining the sustainable development of the ecological environment. The Yuanmou Basin is a typical ecologically vulnerable area in the southwestern mountainous region of China, where issues such as soil erosion are pronounced, becoming one of the main factors restricting regional economic development. This study selected the Yuanmou Basin as the study area, and, using land use data from 2000, 2010, and 2020, constructed an LER assessment model based on disturbance and vulnerability. By integrating elevation and topographic position index data, we examined the spatiotemporal evolution characteristics of LER under different terrain gradients. The LER assessment results are summarized as follows: (1) From 2000 to 2020, the land use types of the Yuanmou Basin were mainly grassland, forest land and cropland. The land use showed a sharp increase in the cropland area and a simultaneous decrease in the grassland area, indicating a main land use evolution direction from grassland to cropland. (2) Over the span of 20 years, the average landscape ecological risk in the Yuanmou Basin slightly increased, specifically manifesting as a significant reduction in low ecological risk areas, while areas of medium and slightly lower ecological risks saw an increase. (3) The spatial distribution of LER in the Yuanmou Basin presents a pattern of being low on the periphery and high in the center, with significant positive spatial correlation, obvious spatial aggregation, as well as “high-high” and “low-low” clustering. (4) Low- and lower-risk areas in the Yuanmou Basin are distributed in the non-arid thermal zone and the medium–high terrain zone, while areas of medium, higher and high risk levels are mainly distributed in the arid thermal zone and the low terrain zone. The research results provide a scientific basis for optimizing and developing the land resources of the Yuanmou Basin.

Land cover flows and land use intensity in the three decades of the post-communist Czechia: Changing trends and driving forces

The land system faces many pressures from the provision of biomass resources and space to the economy. The need to understand land use and cover changes and its drivers is of high importance. This work presents an innovative approach by applying a transdisciplinary approach combining the methods of spatial analysis Land Cover Flows with the methods from the concept of socio-economic metabolism, Material and Energy Flow Accounting, Human Appropriation of Net Primary Production (HANPP) and Final Energy Return on Investment (FEROI). Our main aim is to identify the main land use changes and land cover flows, link them to the underlying socio-economic processes and interpret them in a historical context. Our results show that the overall land use intensity is growing although the positive trends of growing grasslands and forests started after the collapse of communism. The growing intensity of agricultural production with increasing suburbanization reversed these trends. Until the 2000s the HANPP decreased but at the end of the period increased from 55% in 2012 to 70% in 2018. Volumes of the extraction of agricultural biomass are growing while the area of agricultural land has decreased. FEROI grew and stabilized to around 1.0 in the last period (2012–2018) comparable to the value found in the year 2001. The suburbanization rates peaked after the year 2000 at 250 m2/km2/yr.

Landscape Pattern Identification and Ecological Risk Assessment Employing Land Use Dynamics on the Loess Plateau

The Loess Plateau region is characterized by fragmented habitats and ecological vulnerability. Analyzing the changes in land use and ecological risk within the region is of great significance for promoting high-quality development of the Loess Plateau. The study utilized land use data from 2000, 2010, and 2020 in the Loess Plateau region to assess the spatio-temporal variation in land use patterns and landscape ecological risks, aiming to provide valuable references and decision support for ecological risk management and sustainable development in the area. The results indicated that the main land use types in the region are grassland and cropland. From 2000 to 2020, forest, grassland, and water areas increased by 1.39 × 106, 6.25 × 105, and 7.09 × 104 ha, respectively. The impervious area increased rapidly, growing from 9.77 × 104 ha in 2000 to 1.85 × 106 ha in 2020. The cropland decreased by 1.82 × 106 ha from 2000 to 2020, with 4.61 × 105, 4.95 × 106, and 8.91 × 105 ha of cropland converted to forest, grassland, and impervious area, respectively. The fragmentation of the ecological landscape in the region has decreased, and the diversity and richness of landscape types have increased. The fragmentation of cropland, forest, and grassland has decreased, and landscape patches have become more concentrated. High-value areas of landscape ecological risk in the region show a trend of continuous aggregation, altering the dispersion pattern of high-risk areas. Currently, high-risk areas of landscape ecology in the Loess Plateau region are mainly concentrated in northern Shaanxi and some areas along the Yellow River, such as Yulin, Yan’an, Ordos, and others. Currently, the ecological environment remains a bottleneck constraining the high-quality development of the Loess Plateau. It is necessary to persist in coordinated governance and ecological engineering construction, and improving the quality of ecological environment is a prerequisite for consolidating the social foundation and leading the high-quality development of the ecological industry on the Loess Plateau.

Spatial Zoning of the Value Realization Models for Ecological Products in Shibing Karst Natural World Heritage Site

Natural World Heritage properties provide humanity with a rich and diverse range of ecological products, and the realization of their economic value is related to heritage protection and the improvement of community residents’ well-being. In this study, the equivalent factor method was used to calculate the ecological product value (EPV), and the fishnet tool in ArcGIS was used for spatial zoning. The main land use type of the study area is forest land, accounting for over 82% of the total area. The conversion of land use types is weak in the property and strong in the buffer zone. The EPV of the study area was about USD 172.41 million, showing a downward trend before World Heritage inscription but an upward trend after the inscription, with forests as the main contributor. The spatial distribution of the ecosystem service value of the study area has obvious hierarchical characteristics. World Heritage inscription is beneficial for maintaining the stability of land use and for the improvement of the EPV of the property. The high- and low-EPV areas, respectively, are related to the distribution of forests and agricultural land. The dominant models of EPV in the study area are ecological forestry economy, water economy, and ecological agricultural economy.

China’s National Park Construction Contributes to Carbon Peaking and Neutrality Goals

The official establishment of China’s national parks marks a new stage in the construction of China’s ecological civilization system. National parks systematically protect the areas with the richest biodiversity and the most complete ecosystem processes in China. This is beneficial not only for China’s natural conservation work, but also for the world’s response to environmental issues, such as climate change. Based on remote sensing images of land use in the four periods 1990, 2000, 2010, and 2020, this study calculated the land use changes in each national park during the corresponding period. Using the Plus model LEAS module, the driving factors of land use change in the national parks were studied and explored. In addition, the study used the InVEST model carbon storage module, using remote sensing images from different periods and the corresponding carbon pools of each national park as the basic data for model operation, to obtain the carbon storage changes in each national park over the past 30 years. Based on the hotspot analysis function, the hotspot areas of carbon storage changes in the national parks in the past 30 years were determined. Consequently, based on the CARS module of the PLUS model, the carbon storage in Northeast Tiger and Leopard National Park in 2030 was estimated under different scenarios. Research suggested that, except for Sanjiangyuan National Park where grassland is the main land use type, the other four national parks are all dominated by forests, and the expansion and changes in the main land use types were due to human activities. In the past 30 years, the carbon storage in China’s national park ecosystem has mainly shown a trend of first increasing and then gradually decreasing. Based on the changes in carbon storage in the national park, restoration scenarios were simulated for the core protected and generally controlled areas of Northeast Tiger and Leopard National Park. Under the ideal scenario, the highest value of carbon storage would be achieved by 2030, which would be 7,468,250 t higher than that in 2020. The present study provides a reference for the regional management of China’s national parks and further confirms that the implementation of the national park system can enhance China’s ability to achieve carbon peaking and neutrality goals.

Uncovering the effects of policies, climate, and economic development on carbon neutrality in southern Tibet, China

Partitioning the contributions of climate, economic growth, and policy to a region’s carbon flows is an important process for the Chinese government seeking to optimize their regional development policies to achieve carbon neutrality by 2060. A combination of the carbon emission analysis and human appropriation of net primary production (HANPP) framework was applied to a village in the Lhasa river valley, Tibet, to quantify the contributions of these different factors to carbon flows and neutrality. From 2010 to 2019, the average annual net sequestration of CO2 was 374.9 g CO2 m−2 a−1. Changes in climate conditions and the regional policy of Grassland Ecological Protection Subsidy and Reward increased carbon sequestrations by 409.5 and 25.7 g CO2 m−2 a−1, respectively. Socioeconomic development, policies for reducing poverty, and promotion of forage production led to the increase in CO2 emissions by 103.5, 88.8, and 4.3 g CO2 m−2 a−1, respectively. The cumulative CO2 emissions (including HANPP) caused by land use were 298.92 Tg CO2 (2479.63 g CO2 m−2; 1 Tg = 1012 g), while the cumulative CO2 emissions due to energy use were only 11.22 Tg CO2 (93.07 g CO2 m−2), equal to 3.75% of the CO2 emissions driven by land use. Livestock grazing and cropland cultivation were the two main land use factors affecting the carbon balance. We argue that unhooking economic growth from traditional nomadic animal husbandry and lifestyles through policy optimizations would highly contribute the carbon neutrality in Tibet.

Temporal–spatial dynamics of typical ecosystem services in the Chaobai River basin in the Beijing-Tianjin-Hebei urban megaregion

Human demand for ecosystem services dominates ecosystem changes and impacts the temporal–spatial patterns of ecosystem services and their trade- offs. In the process of urbanization, the supply service, regulation service, and cultural service of the ecosystem are difficult to improve in synergy in the city and its surrounding areas, which is tough for urban construction and development. This study took the Chaobai River basin located in the Beijing-Tianjin-Hebei urban megaregion in northern China as the research area. The temporal and spatial changes from 2000 to 2015 of three typical ecosystem services in the study area, including food production, water conservation, and recreation, were evaluated and analyzed through modeling. The ecosystem service hotspots, service-gain areas, and service-loss areas were identified based on spatial analysis. The dynamic change mechanism of ecosystem services was explored from the perspective of land use change and hotspot analysis. The results showed that (1) recreation and food production services showed an increasing trend, while water conservation showed a fluctuating increasing trend. (2) The service-gain area was significantly larger than the service-loss area. (3) The main land use change form in the study area during the study period was the regional conversion of cultivated land to forest land and construction land, which led to the increase in water conservation services and the reduction of food production services in the corresponding patches. However, this conversion did not affect the overall improvement of the three ecosystem services in the study area. (4) Ecosystem service hotspots have gradually changed from being single-service dominant to two co-leading services. The area of food production-recreation hotspots continued to increase, indicating synergy between them. The area of water conservation-recreation hotspots continued to decrease, indicating trade-offs between them. Different types of ecosystem services improve in synergy in the Beijing-Tianjin-Hebei urban megaregion in the process of urbanization through the improvement of agricultural technology and productivity and the promotion of leisure and sightseeing agriculture. This provides an example for other cities.

Spatial-temporal Changes of Land Use/Cover and Its Impact on Evapotranspiration in Wuwei City

In order to grasp the sustainable development path of economy and ecology in Wuwei, based on GlobeLand30 land use/cover data from 2000 to 2020, we analyzed the spatial and temporal characteristics of land use/cover changes in Wuwei through single land use dynamic attitude, comprehensive land use dynamic attitude and land use transfer matrix, and combined with meteorological data and evapotranspiration data, clarified the driving mechanism of land use/cover change and its impact on evapotranspiration. The results show that during the period 2000—2020, shrublands and woodlands in Wuwei City had the highest combined motility, indicating that both were less stable. The main land use transfer direction in Wuwei City during 2000—2020 showed the transfer of cropland to man-made surface, forest land to grassland, and bare land to cropland and man-made surface. The distribution of ET in Wuwei City has strong spatial differences, which is very consistent with the land use/cover and surface vegetation coverage in Wuwei City. Conclusion: Temperature and rainfall have relatively limited effects on land use/cover changes in Wuwei, and only have some effects on land use/cover types such as wetlands, water bodies and woodlands. The main driving forces of land use/cover changes in Wuwei are socio-economic factors, among which GDP, real estate investment and government policies have significant effects on land use/cover type changes. The change of ET in Wuwei City is affected by both climate change and land use/cover change, and from 2010 to 2020, land use/cover dominates.

Biomonitoring for Watershed Protection from a Multiscale Land-Use Perspective

The types and intensification of land use in the watershed affect the living organisms in aquatic ecosystems differently; this impact will also vary according to temporal and spatial scales. Understanding these interactions is crucial in the design of biomonitoring programs to detect the effect of different pollutants in freshwater ecosystems and improve watershed management and conservation strategies. Therefore, this paper qualitatively reviews biomonitoring studies in freshwater ecosystems to evaluate the impact of different land use types on multiple scales in watersheds. The paper is organized into four sections. The first section presents biomonitoring in different freshwater systems (streams, rivers, lakes, and reservoirs). In the second section, we describe the biomonitoring characteristics of the main land use types. In the third section, we explain how spatial and temporal scales affect biomonitoring. Finally, in the fourth section, we focus on biomonitoring planning and future prediction and discuss how to design biomonitoring programs and how to use models and eDNA in biomonitoring. Our review will assist in decision-making regarding biomonitoring programs in watersheds and will guide future studies on the different bioindicators for various land use types in diverse ecosystems worldwide.

Spatiotemporal patterns and driving factors of evapotranspiration (natural and artificial) in the Ziya River Basin, China

Evapotranspiration (ET) accounts for 60%-70% of terrestrial precipitation. Accurately calculating ET has always been one of the hot issues in ecohydrological research. Watershed ET includes natural ET and artificial ET. Natural ET includes vegetation transpiration, bare land evaporation (the two called land ET) and water surface evaporation. Artificial ET mainly refers to irrigation ET, that is, ET generated by human activities. Estimating total ET is the premise of watershed ET management. In this paper, we used the Penman‒Monteith model to estimate land ET, the Dalton model to estimate water surface evaporation, and the AquaCrop model to estimate ET generated by agricultural irrigation water in the Ziya River Basin from 2005 to 2015. Based on the integrated watershed evapotranspiration model, the effects of driving factors on ET were quantitatively analysed. The results showed that the Penman‒Monteith model, Dalton model and AquaCrop model had high simulation accuracy. The total ET fluctuated between 418.4 and 452.3 mm/yr, and the annual average ET was 437.5 mm/yr. The ET of the main land use types was ranked as woodland (496.7 mm/yr) > arable land (468.9 mm/yr) > grassland (320.0 mm/yr). Spatially, the ET in mountainous areas was lower than that in plain areas. The distribution of ET in the total amount, mountainous and plain areas, woodland, grassland and arable land showed a significant Gaussian distribution. Temporally, the interannual variation was small, and the intra-annual difference was mainly caused by climate factors. The conversion of grassland and woodland into arable land had the greatest impact on the total ET. Temperature, precipitation and leaf area index had a positive impact on ET. The impact of land cover change on ET was more significant than that of climate factors. This study can provide an integrated approach for ET estimation in water resource management and land planning.

Geo-Tile2Vec: A Multi-Modal and Multi-Stage Embedding Framework for Urban Analytics

Cities are very complex systems. Representing urban regions are essential for exploring, understanding, and predicting properties and features of cities. The enrichment of multi-modal urban big data has provided opportunities for researchers to enhance urban region embedding. However, existing works failed to develop an integrated pipeline that fully utilizes effective and informative data sources within geographic units. In this article, we regard a geo-tile as a geographic unit and propose a multi-modal and multi-stage representation learning framework, namely Geo-Tile2Vec, for urban analytics, especially for urban region properties identification. Specifically, in the early stage, geo-tile embeddings are firstly inferred through dynamic mobility events which are combinations of point-of-interest (POI) data and trajectory data by a Word2Vec-like model and metric learning. Then, in the latter stage, we use static street-level imagery to further enrich the embedding information by metric learning. Lastly, the framework learns distributed geo-tile embeddings for the given multi-modal data. We conduct experiments on real-world urban datasets. Four downstream tasks, i.e., main POI category classification task, main land use category classification task, restaurant average price regression task, and firm number regression task, are adopted for validating the effectiveness of the proposed framework in representing geo-tiles. Our proposed framework can significantly improve the performances of all downstream tasks. In addition, we also demonstrate that geo-tiles with similar urban region properties are geometrically closer in the vector space.