Intensive Human Activities Research Articles

Spatiotemporal differences in and influencing effects of per-capita carbon emissions in China based on population-related factors

Intensive human activities and resource consumption in China have led to increasing carbon emissions, placing enormous pressure on achieving sustainable development goals. Nonetheless, the effects of population-related factors and carbon emissions remain controversial. This study focuses on the spatiotemporal differences in and influencing effects of per-capita carbon emissions using 2010–2019 panel data covering 30 regions in China. Differing from previous studies, population-related factors are employed to classify the 30 regions into 4 classes, and kernel density estimation, σ convergence and spatial econometric models are used to analyse the spatiotemporal differences in and influencing effects of per-capita carbon emissions. The results demonstrate that overall per-capita carbon emissions rose, but there was heterogeneity in the change in per-capita carbon emissions in the 4 classes of regions. The difference in regional per-capita carbon emissions has been widening, but the change rate of the difference stabilized. Overall, per-capita carbon emissions are heavily affected by household size; however, the driving forces behind per-capita carbon emissions in the 4 classes of regions vary. These results suggest that precise and coordinated governance of carbon emissions and reverting to the traditional household structure should be considered to meet the dual carbon goal.

Benthic Respiration and Heavy Metal Benthic Fluxes in Artificial Shihwa Lake: Approaching In Situ Measurement

This study assessed the impact of intensive human activities on organic matter (OM) and heavy metal cycles in Shihwa Lake, South Korea. Sediment oxygen demand (SOD), benthic nutrient flux (BNF), and benthic heavy metal flux were estimated using in situ benthic chambers. The combined analysis of sediment trap and SOD showed that the vertical supply of OM was a major controlling factor for benthic respiration. The BNF accounted for 35–144% and 32–184% of the N and P required, respectively, for primary production (PP) in the water column. The higher SOD may have also accelerated the release of Mn, Fe, Co, and Ni from the sediment. Benthic fluxes of Cr, As, Cd, Pb, Cu, and Zn were highest near the industrial complex, with ranges of 1.3 ± 0.9, 6.4 ± 4.9, 0.2 ± 0.1, 0.5 ± 0.4, 7.7 ± 1.4, and 452 ± 133 μmol m−2 d−1, respectively. Mn, Fe, Co, As, Pb, Ni, and Cu contributed more than 10% of the sediment to the current standing stock at Shihwa Lake.

Analysis of coastline changes under the impact of human activities during 1985-2020 in Tianjin, China.

The accurate evaluation of shoreline movement is a crucial aspect for managing highly dynamic coasts. This study employed Landsat TM and OLI data through the Digital Shoreline Analysis System model to quantify changes in the spatiotemporal distribution of Tianjin's coastline from 1985 to 2020. The results showed that the coastline length (CL) increased by 178 km and 151% over the past 36 years, with an average increase of 5.1 km/a. Accretion and erosion processes along the entire coast were observed at rates of 83.9% and 16.1%, respectively. Notably, the Tianjin Port Area and Nangang Industrial Zone showed remarkable changes in the shoreline in 2009. Night lights (NL) were used to display the intensity of human activity in this area, and the spatial heterogeneity of night light intensity was significant. Compared to the total night light (TNL) in 1985, it increased by 116% in 2020. The relationship between TNL and CL was then established and displayed a significant positive correlation (r = 0.91). With the increasing total night light, the growth of the CL presented changes with an initial slow increase, then rapid increase, and finally slow increase. In the second phase of TNL, the CL experienced a considerable increase due to anthropogenic activities such as land reclamation and port construction, fueled primarily by government policies during the period of 2005-2013. Subsequently, there was little change in the coastline. These findings provide valuable insights into spatiotemporal coastline monitoring programs and sustainable coastal management.

Spatiotemporal evolution and impact mechanism of ecological vulnerability in the Guangdong–Hong Kong–Macao Greater Bay Area

The constant conflict between the rapidly developing socioeconomic and ecological environment within the Guangdong–Hong Kong–Macao Greater Bay Area necessitates the exploration of ecosystem vulnerability patterns and driving mechanisms. A comprehensive social–economic–ecological framework is proposed to assess the ecosystem vulnerability pattern of the Greater Bay Area, specifically spanning from 1990 to 2020. Employing geographic detectors and weighting methods, the study quantifies spatiotemporal variation and the underlying mechanisms driving vulnerability in the study area. The results demonstrate an obvious trend in ecosystem vulnerability index (ESVI) across the Greater Bay Area, with an initial decline followed by gradual increase during the1990–2020. A substantial majority of the region (approximately 63.85% of the total area) experienced a decline in ESVI from 1990 to 2010. Moreover, the spatial distribution of this decline exhibited a prevailing east-to-west pattern, indicating an overall southward shift over time. Furthermore, a decline was primarily concentrated in the central region and the rapidly expanding urban areas situated on both sides of the Pearl River estuary. Encouragingly, a notable amplification in ESVI was observed between 2010 and 2020, which is attributed to the development, utilization, and protection of land, forests, water bodies, and other pertinent factors associated with urban expansion. The impact of climate change on ESVI changes exhibits a growing magnitude over time, while human activities persist as the predominant driver of ESVI changes. The natural factors exerted a substantial impact on ESVI changes primarily in the upper reaches of the Pearl River, which included topographic relief, precipitation, water network density, biological abundance, and related aspects. Conversely, the pronounced influence of human activities on ESVI changes predominantly manifests within the urban agglomeration of the Pearl River Delta. Key contributors to such a manifestation encompass land change types, intensity of human activities, population density, and related variables. Changes in land use have the potential to induce heightened ecological vulnerability changes. The amelioration of ecological protection and land use practices can be mitigated and reduced by employing ESVI. Moreover, the framework introduced in this study holds the potential to extend vulnerability assessments to other regions with similar ecosystem types. It is expected that the findings derived from this framework could contribute to the formulation of policy recommendations pertaining to ecosystem protection and management.

Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China

Suzhou City, located in the Yangtze River Delta in China, is prone to flooding due to a complex combination of natural factors, including its monsoon climate, low elevation, and tidally influenced position, as well as intensive human activities. The Large Encirclement Flood Control Project (LEFCP) was launched to cope with serious floods in the urban area. This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city. Therefore, this study developed a distributed flood simulation model in order to understand this transition of flood processes. The results revealed that the LEFCP effectively protected the urban areas from floods, but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city. With rainstorm frequencies of 10.0% to 0.5%, the water level differences between two representative water level stations (Miduqiao (MDQ) and Fengqiao (FQ)) located inside and outside the LEFCP area, ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m, respectively. In addition, the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h, respectively. Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed according to flood simulations under seven scheduling scenarios. This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.

Framing future trajectories of human activities in the German North Sea to inform cumulative effects assessments and marine spatial planning

The global industrialization of seascapes and climate change leads to an increased risk of severe impacts on marine ecosystem functioning. While broad scale spatio-temporal assessments of human pressures on marine ecosystems become more available, future trajectories of human activities at regional and local scales remain often speculative. Here we introduce a stepwise process to integrate bottom-up and expert-driven approaches for scenario development to inform cumulative effects assessments and related marine spatial planning (MSP). Following this guidance, we developed optimistic, realistic, and pessimistic scenarios for major human pressures in the German North Sea such as bottom trawling, offshore wind, nutrient discharge, and aggregate extraction. The forecasts comprise quantitative estimates in relation to spatial footprint, intensity, and technological advancements of those pressures for the years 2030 and 2060. Using network analyses, we assessed interactions of the current and future trajectories of pressures thereby accounting for climate change and the growing need for marine conservation. Our results show that future scenarios of spatial distributions could be developed for activities that are spatially refined and included in the current MSP process. Further our detailed analyses of interdependencies of development components revealed that forecasts regarding specific targets and intensities of human activities depend also strongly on future technological advances. For fisheries and nutrient discharge estimates were less certain due to critical socio-ecological interactions in the marine and terrestrial realm. Overall, our approach unraveled such trade-offs and sources of uncertainties. Yet, our quantitative predictive scenarios were built under a sustainability narrative on a profound knowledge of interactions with other sectors and components in and outside the management boundaries. We advocate that they enable a better preparedness for future changes of cumulative pressure on marine ecosystems.

Modern pollen assemblages of agricultural land, wasteland, and natural vegetation in China and their significance for reconstructing the intensity of agricultural activity

Knowledge of the modern pollen assemblage characteristics of artificial and disturbed vegetation can help reconstruct changes in the intensity of human activity and land use/land cover (LULC) based on Holocene stratigraphic pollen records. We obtained pollen assemblage data from 217 agricultural land (cultivated cereals) sites, 79 wasteland sites, and 389 natural vegetation sites in different regions in China. The results show that the pollen of cereals Poaceae and the associated agricultural weeds in agricultural land and wasteland vegetation contexts are effective indicators of the intensity of agricultural activity, and that the pollen assemblages of natural vegetation accurately reflect the regional zonal vegetation composition. Although the cereals Poaceae proportion varied greatly among the agricultural sites in different regions, due to factors like cultivation practices, crop types, and terrain, all of them were significant indicators of agricultural activity. The pollen assemblages of wasteland and natural vegetation in different regions were also different, and the indicator taxa exhibit distinct zonal characteristics. There was no consistent linear relationship between cereals Poaceae proportion and the area of agricultural land. The cereals Poaceae proportion did not vary with increasing agricultural area in regions with higher or lower levels of agricultural production; only in Northeast and North China, when the agricultural area was below 60%, did the cereals Poaceae proportion increase with increasing agricultural area. These results provide a modern process basis for the use of stratigraphic pollen data to reconstruct past changes in agricultural activity and LULC.

Analyzing the Factors Driving the Changes of Ecosystem Service Value in the Liangzi Lake Basin—A GeoDetector-Based Application

The Liangzi Lake Basin (LLB) is an important ecological buffer for Wuhan’s urban agglomeration. It involves the ecological security of the middle reaches of the Yangtze River. Historical land misuse has altered the topography and impacted the ecosystem services value (ESV). Amid urbanization, it is vital to highlight changing land use methods and their effects on ESV valuation, understanding the underlying drivers comprehensively. The research is centered on the LLB as its designated study region, and utilizes remote sensing satellite data spanning from 2000 to 2020. This data is combined with a value equivalence table to quantify ESV. The GeoDetector method is employed to investigate the driving factors behind ESV fluctuations. The findings indicate a substantial shift in land use patterns within the LLB between 2000 and 2020. Notably, arable land decreased by 6.28% and water bodies decreased by 0.92%, while built-up areas expanded by 5.14% and forest land expanded by 2.05%. During this period, the LLB’s ecosystem services value decreased by approximately 2.035 billion yuan. This drop was mainly due to reduced water areas resulting from urbanization, negatively impacting the ecological regulatory services provided by these water bodies. Based on the geoprobe model, possible drivers of changes in ESV in the LLB were identified, with human activity intensity and NDVI detection results being the most obvious. The research emphasized protecting and restoring key ecological areas, like water bodies and forests, to maintain a delicate balance between the environment and socio-economic development. Additionally, they exemplify the effectiveness of ecological policies, including initiatives such as “Returning Farmland to Forest or Pasture” (RFFP), and the prohibition of lake and field reclamation.

Expanding our view of the cold-water coral niche and accounting of the ecosystem services of the reef habitat

Coral reefs are iconic ecosystems that support diverse, productive communities in both shallow and deep waters. However, our incomplete knowledge of cold-water coral (CWC) niche space limits our understanding of their distribution and precludes a complete accounting of the ecosystem services they provide. Here, we present the results of recent surveys of the CWC mound province on the Blake Plateau off the U.S. east coast, an area of intense human activity including fisheries and naval operations, and potentially energy and mineral extraction. At one site, CWC mounds are arranged in lines that total over 150 km in length, making this one of the largest reef complexes discovered in the deep ocean. This site experiences rapid and extreme shifts in temperature between 4.3 and 10.7 °C, and currents approaching 1 m s−1. Carbon is transported to depth by mesopelagic micronekton and nutrient cycling on the reef results in some of the highest nitrate concentrations recorded in the region. Predictive models reveal expanded areas of highly suitable habitat that currently remain unexplored. Multidisciplinary exploration of this new site has expanded understanding of the cold-water coral niche, improved our accounting of the ecosystem services of the reef habitat, and emphasizes the importance of properly managing these systems.

Coupling RESI with Multi-Scenario LULC Simulation and Spatiotemporal Variability Analysis: An Ecological Spatial Constraint Approach

Southwest China’s arid river valleys represent ecologically vulnerable areas with intense human activity. Understanding the historical changes in LULC and land cover and projecting the impacts of various development scenarios on future LULC have become crucial for regional spatial information management and territorial spatial planning. This research analyzes the land-use changes in the Yuanmou dry-hot valley over a 30-year span from 1990 to 2020. Building upon the PLUS model, we established a coupled habitat quality spatial and multi-scenario land-use simulation model. Four development scenarios were proposed: natural progression, economic development, ecological conservation, and balanced development. We conducted simulations and evaluations of land-use in the Yuanmou dry-hot valley for 2030 using the PLUS mode, assessing the sustainability of future development scenarios under varying ecological constraints. During the simulation, three distinct RESI regions were employed as restricted development zones, integrating the three ecological constraints with the four simulation scenarios. We introduced a novel approach based on ecological environmental quality as the ecological constraint, providing a scientific reference for sustainable development in ecologically vulnerable areas. The results indicate that under ecological conservation scenarios with high-to-low RESI constraints, the ecological environment is superior to the other three scenarios. The results show the following: (1) From 1990 to 2020, aside from a continuous decrease in grassland area, there was an increasing trend in the areas of water bodies, forests, croplands, construction lands, and unused lands in the Yuanmou dry-hot valley. (2) By 2030, under all four development scenarios, the cropland area is expected to expand rapidly, while forested areas will decrease; grassland areas will decline under natural and economic development scenarios but show opposite trends under the other scenarios; and construction land and unused land areas will decrease under the ecological conservation and balanced development scenarios. (3) Land-use intensity analysis for the four scenarios indicated that, by 2030, unused lands in the Yuanmou dry-hot valley are more likely to be converted into water bodies, forests are more likely to be converted into croplands and grasslands, grasslands are more likely to be converted into croplands, croplands are more likely to be converted into grasslands, and construction lands are more likely to become unused lands. (4) Sustainable LULC management evaluations based on landscape indices reveal that ecological conservation and balanced development scenarios exhibit superior landscape connectivity and clustering. Thus, the balanced development scenario is the most appropriate LULC strategy for the Yuanmou dry-hot valley in the future. These findings provide scientific references for balancing ecological conservation and economic development in the arid river valleys of Southwest China.

Elevated CO2 Can Improve the Tolerance of Avena sativa to Cope with Zirconium Pollution by Enhancing ROS Homeostasis.

Zirconium (Zr) is one of the toxic metals that are heavily incorporated into the ecosystem due to intensive human activities. Their accumulation in the ecosystem disrupts the food chain, causing undesired alterations. Despite Zr's phytotoxicity, its impact on plant growth and redox status remains unclear, particularly if combined with elevated CO2 (eCO2). Therefore, a greenhouse pot experiment was conducted to test the hypothesis that eCO2 can alleviate the phytotoxic impact of Zr upon oat (Avena sativa) plants by enhancing their growth and redox homeostasis. A complete randomized block experimental design (CRBD) was applied to test our hypothesis. Generally, contamination with Zr strikingly diminished the biomass and photosynthetic efficiency of oat plants. Accordingly, contamination with Zr triggered remarkable oxidative damage in oat plants, with concomitant alteration in the antioxidant defense system of oat plants. Contrarily, elevated levels of CO2 (eCO2) significantly mitigated the adverse effect of Zr upon both fresh and dry weights as well as the photosynthesis of oat plants. The improved photosynthesis consequently quenched the oxidative damage caused by Zr by reducing the levels of both H2O2 and MDA. Moreover, eCO2 augmented the total antioxidant capacity with the concomitant accumulation of molecular antioxidants (e.g., polyphenols, flavonoids). In addition, eCO2 not only improved the activities of antioxidant enzymes such as peroxidase (POX), superoxide dismutase (SOD) and catalase (CAT) but also boosted the ASC/GSH metabolic pool that plays a pivotal role in regulating redox homeostasis in plant cells. In this regard, our research offers a novel perspective by delving into the previously unexplored realm of the alleviative effects of eCO2. It sheds light on how eCO2 distinctively mitigates oxidative stress induced by Zr, achieving this by orchestrating adjustments to the redox balance within oat plants.

Response of the Biological Components to Climate Change in the Wetland Ecosystem of the Qinghai-Tibet Plateau

Alpine wetlands play a role in water conservation, climate regulation, carbon sequestration, and biodiversity protection. However, due to the unique geological structure and climate characteristics of alpine areas, climate change is highly likely to have an impact on alpine wetlands and their ecosystems, including the abundance and distribution of local species. This paper focuses on analyzing the composition, quantity, and distribution changes of wetland organisms, including producers, consumers, and decomposers. The research findings indicate that, with the intensification of human activities and climate change such as global warming, despite the emergence of some new wetlands, many natural alpine wetlands on Qinghai-Tibet Plateau are facing shrinkage and are gradually retreating towards higher altitudes, latitudes, and wetter areas, which means the extinction of some plants and the shrinkage of wildlife habitats. Changes in wetland environment, such as drying, resulting from increased temperature and decreased precipitation, have led to a decline in biodiversity and degradation of alpine wetland ecosystems. Despite an overall increase in vegetation cover, wetland degradation has caused changes in plant species diversity and community composition. Climate warming have also affected wildlife migration and the activity of microorganisms. The changes in plateau wetlands are primarily shaped by climate conditions, while human activities act as accelerators, causing significant damage to wetland environments, leading to fragmentation and accelerated degradation. This paper proposes strengthening ecological monitoring and risk assessment in these regions, conducting further research, and promptly implementing necessary restoration measures to reduce the ecological risks caused by these changes.

Inventory Results of 101 Natural Forests in the Middle Hills of Nepal over Two Decades

Repeated forest-resource inventories provide indispensable information to evaluate, for example, the mean growth rate of stands and changes in tree-species composition in an area.This paper presents a summary of such longitudinal forest inventory data in the Middle Hills of Nepal, where deforestation has been an issue. Our first inventory was implemented between 1997 and 1999 and measured 3839 plots of 100 square meters (m 2 ). Our second inventory was conducted between 2014 and 2016 and measured 3765 plots of 100 m 2 . We found that over these two decades, the number of trees per hectare (ha -1) significantly improved. The number of stands ha -1 with diameter at breast height (DBH) of 10 centimeters (cm) and above went from 361.2 in the first inventory to 466.2 in the second inventory. We also found that not only the number of stands but also the quality of stands significantly improved. The number of stands with DBH of 30 cm and above ha-1 increased from 72.9 to 99.6. The mean alpha diversity, the number of trees species in a plot, rose to 2.1 from 1.6 in the initial inventory. In sum,“green has made a bold comeback in the Middle Hills”. Our indices evaluating the intensities of human activities on the plots suggest that these improvements in forest-resource conditions may be due to the decreased use of forests in the Middle Hills over these two decades.

The first baleen whale marine protected area proposed for Bryde's whales in the Beibu Gulf, China

AbstractThe establishment of marine protected areas (MPAs) for cetaceans is an important strategy to mitigate human disturbance and protect biodiversity. Despite abundant cetacean species, there are only a few MPAs dedicated to cetacean conservation in China, all of which are for inshore dolphins. Bryde's whales, the only nearshore baleen whale population in mainland China, are conflicting with intensive human activities, yet an effective conservation strategy is lacking. This study used species distribution models to analyze distribution patterns and suitable habitats of Bryde's whales in the Beibu Gulf and proposes the first baleen whale MPA in China. Our results showed Bryde's whales have a seasonal distribution pattern in the Beibu Gulf, and that the waters around Weizhou Island and the southeastern coast of Vietnam were their core habitats. The seasonal nighttime light data indicated a negative relationship between the number of ship lights and Bryde's whale sightings and suggest that Bryde's whales might be threatened by fisheries. We proposed an MPA based on the results, suggesting that the waters within 20 km around Weizhou Island should be declared a protected area. Furthermore, we recommend that anthropogenic activities in the waters around Weizhou Island are better managed to reduce negative impacts on marine life.

A quantitative framework to evaluate urban ecological resilience: broadening understanding through multi-attribute perspectives

Intensive human and economic activities in urban areas have had adverse effects on local resources and ecology, leading to a decline in ecological resilience. Enhancing ecological resilience is crucial for improving the urban ecosystem's ability to withstand and recover from external risks. However, quantitative research on urban ecological resilience remains somewhat ambiguous, with many studies lacking comprehensive assessment methods from multiple perspectives. In this study, we established a comprehensive framework to assess urban ecological resilience based on four regime attributes. The study's results indicated the following key findings: The average urban ecological resilience value exhibited a trend of initially declining and then recovering. Cities proposed different approaches when considering and managing social and ecological relationships during the development process. A significant correlation between urbanization levels and ecological resilience was observed, with urban ecological resilience increasing in areas with low urbanization levels and sharply decreasing in areas with high urbanization levels. The findings from this study provide a specific theoretical foundation for decision-makers involved in urban planning and development strategies.

Research on the Spatiotemporal Dynamic Relationship between Human Activity Intensity and Ecosystem Service Value in the Three Gorges Reservoir Area

The Three Gorges Dam project and other human activities, including regional urbanization and industrialization, have had a substantial influence on the biological environment of the Three Gorges Reservoir Area (TGRA). They have changed the surface land use pattern, disrupted ecosystem structure and function, and influenced changes in the value of ecosystem services. The human activity intensity (HAI) assessment model, the ecosystem services value (ESV) assessment model, and the bivariate spatial autocorrelation model were used based on the spatiotemporal evolution data of towns along the Yangtze River in the TGRA in 1995, 2000, 2005, 2010, 2015, and 2020. At the same time, the spatiotemporal impact of the HAI on land use patterns was evaluated and the magnitude of the spatiotemporal influences on the ESV was investigated. The findings demonstrate the following: (1) The TGRA’s higher reaches are occupied by forested land, while the middle and lower portions are characterized by agricultural land. Land change in the reservoir region has mostly featured transitions between wooded land, agricultural land, grassland, and building land during the last 25 years. Because of differences in natural geography and administrative divisions, the intensity of human activity in the TGRA changes throughout the Yangtze River, with higher intensity in Chongqing and lower intensity in Hubei. By comparing the ESV and the HAI and validating with Moran scatter plots, it was determined that there is a negative relationship between the value of ecosystem services and the intensity of human activities. (2) The ESV rose from CNY 1017.16 × 108 in 1995 to CNY 1052.73 × 108 in 2020, suggesting that the policies of converting farmland back into forests, eliminating outdated production capacity, and developing green industries, among other ecological conservation measures, are effective. (3) In the research area, the effect coefficient of HAI on ESV ranges from −0.02 to −0.032 to −0.031. This coefficient represents the correlation between the HAI and ESV and can preliminarily judge the change in the degree of correlation between the HAI and ESV. The increase in HAI leads to a decrease in the value of ecosystem services, and there is a clear negative spatial correlation between the two. The low human activity area and low ecosystem service value area in the Chongqing section have been transformed into a high ecosystem service value area through years of returning farmland to forest and ecological management measures for sustainable development.

Machine Learning-Based examination of recent mangrove forest changes in the western Irrawaddy River Delta, Southeast Asia

Mangrove forests serve as a significant carbon sink and provide effective shoreline protection against devastating winds. However, these forests are facing an unprecedented decline in tropical and subtropical large deltas due to human activities and climate change. This study focuses on quantifying the dynamic changes of mangrove forests in the Western Irrawaddy River Delta (WIDR), which is part of Myanmar’s largest delta in Southeast Asia, Remote sensing images from 1988 to 2022 were utilized alongside a machine learning approach to analyze these changes. The findings demonstrate a significant decline of mangrove forests within the WIRD, with a reduction in area by 45.35% over the past 35 years. Additionally, the patches of mangrove forests have become increasingly fragmented. Losses predominantly occurred in the inland regions, while gains were observed along the seaward edges, suggesting progradation towards the sea, which compensated for a net loss of 2,812.32 ha during the study period. The intensification of human activities, specifically deforestation and aquaculture pond utilization, appears to be the leading cause of catastrophic internal degradation within the WIRD’s mangrove forests. Contrary to the influence of local sea level rise or variations in suspended sediment discharge into the WIRD, this study suggests that the persistent retreat of mangrove forest fringes is controlled by large waves generated by the southwest monsoon. Estuarine barriers situated in the WIRD act as buffers, dissipating wave energy and facilitating seaward growth. of mangrove forests. Our study reveals a significant pattern in the WIRD, where landward mangrove forest loss coincided with seaward mangrove forest gain. This work underscores the importance of addressing landward mangrove forest loss and recognizing the emergence of seaward gains in the WIRD, providing valuable insights for fostering successful and sustainable mangrove management and protection initiatives.

Habitat visibility affects the behavioral response of a large herbivore to human disturbance in forest landscapes

Wildlife can perceive humans as predators and human disturbance, whether lethal (e.g., hunting) or non-lethal (e.g., hiking, biking, and skiing), triggers antipredator behavior among prey. Visibility is the property that relates habitat structure to accessibility of visual information that allows animals to detect predators and evaluate predation risk. Thus, the visibility of a habitat (hereafter referred to as habitat visibility) for prey species alters the perceived risk of predation and therefore has a strong influence on their antipredator behavior. Yet, knowledge of how habitat visibility affects the response of animals to different types of human disturbance is limited, partly, because it is challenging to measure habitat visibility for animals at a fine spatial scale over a landscape, particularly in highly heterogeneous landscapes (e.g., forests). In this study, we employed a newly described approach that combines terrestrial and airborne LiDAR to contiguously measure fine-scale habitat visibility in a forested landscape. We applied the LiDAR-derived habitat visibility to examine how habitat visibility in forests affects the summer space use of 20 GPS-collared female red deer (Cervus elaphus) modeled with integrated step-selection functions in the Bavarian Forest National Park, Germany when exposed to various types of human disturbance including recreational activities, forest roads, hiking trails, and hunting. We found that red deer in our study area avoided areas with higher all types of human disturbance, especially during daylight hours. Furthermore, habitat visibility significantly modified the use of space by red deer in response to human recreational activities, forest roads, and hiking trails, but not to the hunting area. Red deer tended to tolerate a higher intensity of human recreational activities and to use areas closer to forest roads or hiking trails when they have lower habitat visibility (i.e., more cover). Our findings highlight the importance of considering visual perception when studying the response of wild animals to human disturbance. We emphasize the potential to mitigate negative consequences of human disturbance on wildlife, through measures such as maintaining vegetative buffers around recreational infrastructure (e.g., roads and skiing tracks) in order to reduce habitat visibility around areas frequented by humans.

Correlation and trade-off analysis of ecosystem service value and human activity intensity: a case study of Changsha, China

Correlation and trade-off analysis of ecosystem service value and human activity intensity: a case study of Changsha, China

Does cropland threaten urban land use efficiency in the peri-urban area? Evidence from metropolitan areas in China

In recent decades, cropland policies have been recognized as crucial tools for ensuring food security and managing urban growth. However, whether cropland conservation undermines urban land use efficiency (ULUE) in peri-urban areas has not been adequately studied. This study investigated the impact of cropland on ULUE in the peri-urban areas of 36 rapidly urbanizing metropolitan areas in China. Multiple open-source datasets were used, including land use, land cover, three-dimensional building structure, and nighttime light (NTL) data. Urban construction land patterns (infilling, edge, outlying) were categorized to examine the intermediate role of urban form in the correlation between cropland and ULUE. The findings indicated that: (1) high proportion of cropland area within the peri-urban areas significantly undermined ULUE; (2) although the conservation of cropland is conducive to compact urban growth, the infilling expansion pattern that compelled by cropland conservation would not sustain intensive human activity; and (3) reducing the spatial separation between conserved cropland and urban construction land was conducive to the dual objectives of protecting cropland and promoting ULUE. This study contributed to the development of a nuanced understanding of cropland protection policies that balance national food security and urbanization efficiency.