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Exploring NPP changes and their corresponding drivers is significant for the achievement of sustainable ecosystem management and in addressing climate change. This study aimed to explore the spatiotemporal variation in NPP and analyze the effects of vegetation and climate change on the global NPP from 2003 to 2020. Methodologically, the Theil–Sen and Mann–Kendall methods were used to study the spatiotemporal characteristics of global NPP change. Moreover, a ridge regression model was built by selecting the vegetation indicators of the leaf area index (LAI) and fraction vegetation coverage (FVC) and the climate factors of CO2, shortwave downward solar radiation (Rsd), precipitation (P), and temperature (T). Then, the relative contributions of each factor were evaluated. The results showed that, over the previous two decades, the global mean NPP reached 503.43 g C m−2 yr−1, with a fluctuating upward trend of 1.52 g C m−2 yr−1. The regions with a significant increase in NPP (9.22 g C m−2 yr−1) were mainly located in Central Africa, while the regions with decreasing NPP (−3.21 g C m−2 yr−1) were primarily in the Amazon Rainforest in northern South America. Additionally, CO2, the LAI, and the FVC exhibited positive contributions to the NPP trend, with the predominant factors being CO2 (relative contribution of 32.22%) and the LAI (relative contribution of 21.96%). In contrast, the contributions of Rsd and precipitation were relatively low (<10%). In addition, the contributions varied at different land cover and climate zone scales. The CO2, LAI, FVC, and temperature were the predominant factors affecting NPP across the vegetation types. At the scale of climate zones, CO2 was the predominant factor influencing changes in vegetation NPP. As the climate gradually transitioned towards temperate and cold regions, the contribution of the LAI to NPP increased. The findings of this study help to clarify the effects of vegetation and climate change on the ecosystem, providing theoretical support for ecological environmental protection and other related initiatives. [ABSTRACT FROM AUTHOR]

The ecological environment is fundamental to human survival and development, and China has seen a historical shift from localized to widespread improvements in its ecological conditions. Aksu, a typical ecologically sensitive region in Xinjiang, China, is significant for the study of vegetation dynamics and their driving factors, which is crucial for ecological conservation. This study evaluates the spatiotemporal changes in vegetation coverage in Aksu from 2000 to 2020 using long-term Normalized Difference Vegetation Index (NDVI) data and trend analysis. Additionally, this study explores key factors influencing vegetation changes through correlation analysis with temperature, precipitation, and nighttime light data. The results indicate the following: (1) vegetation coverage in Aksu exhibits significant spatial heterogeneity, with annual NDVI increasing at a rate of 0.83% per year (p < 0.05); (2) the influence of temperature and precipitation on NDVI was weakly correlated from 2000 to 2020; and (3) a strong positive correlation was found between nighttime light intensity and NDVI, suggesting that urban development plays a dominant role in vegetation change, while temperature and precipitation have comparatively minor impacts. The findings provide a scientific basis for ecological conservation and sustainable development in the region. [ABSTRACT FROM AUTHOR]

There are increasing concerns about regional ecosystem shifts in the Arctic due to climate change. Notably, warming-induced increases in Arctic vegetation cover can have important consequences for surface energy balance, habitat changes, permafrost, and more. Mammalian herbivory is an important potential force to counteract this effect. In this systematic literature review, we examine the role of terrestrial mammalian herbivory on warming-induced increases in Arctic vegetation. We analyse the effects of terrestrial mammalian herbivory on vegetation cover, abundance, growth, survival, and ecosystem productivity. Our results show that herbivory has an overall significant negative influence on Arctic vegetation, particularly on vegetation biomass, growth, and productivity, as indicated by the Normalised Difference Vegetation Index (NDVI). Importantly, we demonstrated a significant role of herbivores in controlling carbon dioxide exchange and carbon uptake, whilst acknowledging that the relationship between herbivory and ecosystem productivity is highly complex and site-dependent. Our results confirm the important role that herbivory can play in buffering observed and predicted warming-induced Arctic vegetation increases. We also find that this is strongly affected by plant palatability, trampling occurrence, and herbivore density. [ABSTRACT FROM AUTHOR]

Ecological disturbances driving state changes in ecosystems are likely to be exacerbated with climate shifts during this century. Temperate montane ecosystems of the Western United States (Mountain West) are especially vulnerable due to their low fertility, heterogeneous landscapes, and tight coupling between terrestrial and aquatic components. We review how catchment level pulse and press disturbances will intensify, and how they are reflected by coupled measurements of stream water chemistry and flow. Detecting effects on watershed processes can be complex and depend on the type and extent of disturbance. Within this context, we discuss the impacts of wildfire (pulse), bark beetle outbreaks (pulse), snowpack shifts (press), and progressive vegetation community shifts (press) on streamflow and chemistry dynamics (hydrochemographs). We used long-term data from three mid- to high-elevation watersheds as examples of how disturbances may influence stream hydrochemographs, including increased variability in winter nitrate export in more recent years with extremes in snowmelt runoff export; variable nitrate export when snow water equivalent was abnormally high or low; and high nitrate flux in the years immediately following sudden forest loss. These examples illustrate the need for long-term continuous monitoring to fill the gap in our understanding of the short- and long-term consequences of climate change-induced disturbances to watersheds. As disturbances increase in severity and frequency and induce ecological state changes, it is critical that we develop our understanding of impacts on downstream communities that depend sociologically and economically on water availability and quality. [ABSTRACT FROM AUTHOR]

Armed conflicts are acknowledged for their effects on the environment, including ecosystem degradation and biodiversity loss, but also ecological restoration. Both processes impact post-conflict opportunities for peace and development. The armed conflict in Northern Uganda (1986–2008) profoundly affected local communities and their natural environment. While some areas suffered environmental degradation others underwent ecological restoration. Understanding this historical pattern is crucial for post-conflict natural resource management and peace and development prospects. This article aims to analyse vegetation changes in Northern Uganda during and after the conflict, exploring potential drivers of such changes and their implications for sustainable peace and development. Utilising remote sensing analysis and literature review, we observe a post-conflict 'greening' trend alongside a more equal vegetation deterioration and restoration spatial distribution. We propose that if these trends are driven by agriculture expansion, the way this is organised and articulated with natural vegetation will be central for peace and development. [ABSTRACT FROM AUTHOR]

The arid region of Northwest China (ARNC) is responsive to global climate change, and drought events have occurred frequently in recent decades. However, studies about the effect of meteorological and drought stress on vegetation change in the ARNC are still insufficient. In this study, we analyzed the spatiotemporal trends of meteorological factors (temperature, TMP; precipitation, PRE; standardized precipitation evapotranspiration index, SPEI), drought stress factors (vapor pressure deficit, VPD; soil moisture, SM), and vegetation (normalized difference vegetation index, NDVI) during 1982–2021. We also investigated the characteristics of drought events by the run theory, including drought times, drought duration, drought severity, and drought intensity. The impacts of meteorological and drought stress factors on the vegetation were explored using Pearson correlation analysis and the structural equation model (SEM). We found that the annual and growing season TMP, PRE, VPD, SM, and NDVI showed an increasing trend in the ARNC during 1982–2021. In contrast, SPEI exhibited a decreasing trend in the annual and growing season. In addition, the characteristics of the drought events varied significantly in the ARNC. The drought events primarily occurred in the Tarim River Basin, Turpan-Hami Basin, and the Hexi Corridor. The Pearson correlation analysis and SEM results consistently demonstrated that TMP and SM exerted greater impacts on vegetation growth than PRE, VPD, and SPEI. The factors that determine vegetation change were TMP and PRE. Exploration of meteorological and drought stress factors that influence vegetation change is essential for comprehending the influence of dominant factors on vegetation change. [ABSTRACT FROM AUTHOR]

Limestone pavements contain a unique flora, dominated by ferns with a mix of herbaceous species more often found in woodlands, heathlands and grasslands. The crevices between the rocks are known as grikes, they provide a shaded habitat which, depending on pavement structure, can protect plants from grazing. Despite being of conservation importance and supporting a number of rare and scarce plant species there has been very little research into vegetation change in limestone pavements. This study repeated a survey originally conducted between 1972 and 1975. The Ward and Evans survey visited 535 limestone pavement units spread across England, Scotland and Wales and recorded grike vegetation. This study was able to resurvey 516 of those pavements and repeat the survey using the original methods. Expansion of tree and shrub cover has been observed in some pavements but not previously quantified so tree cover was assessed using historic aerial photographs and satellite imagery. On average species richness per pavement increased but there was a very wide range of change in species richness across individual pavement units ranging from a loss of 56 species to an increase of 38. Dissimilarity averaged 0.41. The area of pavement covered by trees or large shrubs increased by 62% between the two surveys but the number of pavements with zero tree cover also increased. Breaking down pavement units into those with low (<5%), medium (5%–30%) and high (>30%) current tree cover shows that species richness increased in open pavements but was reduced in pavements with high tree cover. Pavement units with high tree cover also showed higher dissimilarity and lower levels of indicators of disturbance. In pavements with high tree cover Ellenberg light (L) values were significantly lower than in open pavements. Open pavements showed higher levels of competitive species (based on Grime CSR values) but no change difference in Ellenberg nutrient (N) values. Vegetation in limestone pavements has changed considerably in the period between the two surveys with negative effects of high tree and shrub cover particularly problematic. There is an urgent need for investigation to support management decisions in this habitat. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Questions: At high latitudes, anthropogenic climate change and invasive species threaten biodiversity, often with interacting effects. Climate change not only impacts native plant species directly by driving distribution and abundance of species, but indirectly through the influence on community dynamics and habitat suitability to invasive species. A key obstacle to quantifying vegetation change in the sub‐Antarctic is the scarcity of cloud‐free satellite imagery in a region with near‐permanent cloud cover and lack of long‐term plot data. In this paper, we aim to address the following questions: how has vegetation in the sub‐Antarctic changed between 1965 and 2020? What are the roles of climate change and invasive species in driving these changes? Location: The study was conducted on Marion Island in the sub‐Antarctica. Methods: We quantified vegetation change by analysing repeat ground photography between 1965 and 2020, accompanied by an analysis of climate trends and invasive plant species' cover changes over the same period. Results: Total vegetation cover was significantly higher in 2020 than in 1965 in all habitats other than in the coastal saltspray habitat, indicating an increase in overall biomass on the island. The more responsive 'generalist' plant species have expanded across the island, whilst the more 'specialised' plant species have not significantly changed in cover, with the exception of the mire graminoids, which have declined. Marion Island has thus undergone significant vegetation change, showing a greening trend across most habitats in the last five decades. This has been accompanied by aridification, an increase in mean air temperature, changes in wind direction and wind speed, and an increase in invasive mouse populations. The three most widespread invasive plant species have also expanded their ranges, especially in areas influenced by animal disturbance and nutrient input. Conclusions: In congruence with research from Northern‐hemisphere tundra and other islands in the sub‐Antarctic, these results provide substantive empirical evidence for the interacting effects of climate change and invasive species on sub‐Antarctic tundra vegetation, as has long been predicted. [ABSTRACT FROM AUTHOR]

Extended Abstract Background: Vegetation is one of the main components of biosphere preservation that acts as a link between soil, water, and atmosphere. It is crucial in providing organic matter, regulating the carbon cycle, and exchanging energy on the surface of the earth. In recent years, climate change and global warming have caused frequent events, such as floods, heat waves, and droughts, which can damage terrestrial ecosystems. Climate change directly affects the growth of vegetation; on the other hand, changes in vegetation cover give feedback to climate change by regulating water, energy exchange, and carbon dioxide concentration. Methods: The research was carried out in Mazandaran province to analyze vegetation trend in the study area during the 2001-2020 period. The 16-day composite MODIS-NDVI time series data, named MOD13Q1, with a spatial resolution of 250 meters (920 NDVI images) were used for this purpose. The non-parametric Mann-Kendall method was employed to investigate changes in vegetation activity and trend significance. The overlying vegetation trend map and the location of big cities and main roads of the province were also investigated in this research. Results: A decreasing trend of vegetation cover was observed in 16% of the total studied area, and the rest showed an increasing trend, although the significant decrease and increase of vegetation cover occurred in 5% and 65% of the area, respectively, with a 95% confidence level. The vegetation trend map showed that the most significant reduction of vegetation in the last 20 years occurred in coastal areas and low-altitude regions, especially around big cities and main roads entering the province. Decreased vegetation around the metropolises is expected due to the increase in population and the need for urban development. However, the results showed that the most significant decrease in vegetation occurred in the cities of Mahmudabad (19%), Babolsar (17%), Ghaemshahr (10%), and Jouybar (9%). Unlike the big cities of Sari and Ghaemshahr, the cities of Sorkhrood, Mahmudabad, and Babolsar are at the top of the cities with reductions in vegetation cover in the last 20 years. Unfortunately, this is not due to urban development and increasing population, but drastic changes in the use of agricultural land and citrus orchards and turning them into private villas are the main factor in the reduction of vegetation. Comparing the vegetation trend map with the main roads of the province reveals that a significant reduction of vegetation has occurred around the main roads entering Mazandaran province, especially on the Haraz, Firouzkouh, and Farim roads. In contrast, smaller areas of vegetation cover reduction were observed around the Chalus road. The investigation of the areas with positive vegetation cover trends showed that the highlands of the province, especially the eastern highlands, experienced a significant increase in vegetation cover. However, a less significant positive trend of vegetation was observed in the western highlands. Rather, most of these areas have experienced no trend conditions in the past 20 years, which could be due to the recent global warming and the higher temperature in the east of the province than in the western regions, which generally has caused suitable temperature conditions for the growth of vegetation in the eastern highlands of the province. It seems that the western highlands still do not have suitable temperature conditions for the growth of vegetation. Conclusion: The results of this research show that the changes in vegetation in Mazandaran province are under the control of two natural and human factors, and the former (climate) has caused an increase in vegetation in 65% of the area of the province, especially in the highlands, probably caused by the increase in temperature. The recent global warming has made it possible to provide living conditions for plants in the highlands of the province, especially the eastern highlands. Nevertheless, the human factor has been destroying vegetation throughout the province, especially in tourist areas and those with easy access. As such, a significant trend of vegetation reduction was observed both on the coasts, around metropolises, in the heart of the Hyrkan forests, and in the heights near the main roads. A significant decrease in vegetation cover has occurred in 5% of the area of the province, and these decreases were observed mostly in the plains, coastal strip, low altitudes with low slopes, outskirts of cities, and roads of the studied area. Vegetation is also being destroyed in the marginal areas of the roads from Ramsar to the neighboring western province, Gorgan Sari, Tehran, Chalus, Haraz, and Firuzkouh, which can be the main reason for the increase in traffic load, changes in land use, and the construction of recreational facilities and villas. Based on the results of this research, extreme changes in land use in the last 20 years are very evident, and if the human process of land use change continues along with the loss of water and soil resources, we may see irreparable blows to the ecosystem of the Caspian systems in the near future.

The alpine timberline is a component of terrestrial ecosystems and is highly susceptible to climate change. Since 2000, the Tibetan Plateau's high-altitude zone has been experiencing a persistent warming, clarifying that the response of the alpine timberline to climate warming is important for mitigating the negative impacts of global warming. However, it is difficult for traditional field surveys to clarify changes in the alpine timberline over a wide range of historical periods. Therefore, alpine timberline sites were extracted from 2000–2021, based on remote sensing data sources (LANDSAT, MODIS), to quantify the timberline vegetation growth in the Gexigou National Nature Reserve and to explore the impacts of climate change on timberline vegetation growth. The results show that the mean temperature increased significantly from 2000 to 2021 (R2 = 0.35, p = 0.0036) at a rate of +0.03 °C/year. The alpine timberline continued to shift upwards, but at a slower rate, by +22.87 m, +23.23 m, and +2.73 m in 2000–2007, 2007–2014, and 2014–2021, respectively. The sample plots of the timberline showing an upward shift experienced a decreasing trend. The timberline NDVI increased significantly from 2000 to 2021 (R2 = 0.2678, p = 0.0136) with an improvement in its vegetation. The timberline NDVI is positively correlated with the annual mean temperature (p < 0.05), February mean temperature (p < 0.05), June minimum temperature (p < 0.05), February maximum temperature (p < 0.01), June maximum temperature (p < 0.01), and June mean temperature (p < 0.01). It was also found to be negatively correlated with annual precipitation (p < 0.01). The study showcases the practicality of using remote sensing techniques to investigate the alpine timberline shifts and timberline vegetation. The findings are valuable in developing approaches to the sustainable management of timberline ecosystems. [ABSTRACT FROM AUTHOR]

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Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau. However, the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain unclear. Therefore, clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the region. Here, we investigate NDVI trends using the Normalized Difference Vegetation Index (NDVI) as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the Geodetector. We find a tendency of vegetation greening from 2001 to 2020, with significant greening accounting for 21.44% of the entire region. However, browning area expanded rapidly after 2011. Warmer temperatures are the primary driver of vegetation changes in the Zoige Plateau. Climatic variations and human activities were responsible for 65.57% and 34.43% of vegetation greening, and 39.14% and 60.86% of vegetation browning, respectively, with browning concentrated along the Yellow, Black and White Rivers. Compared to 2001–2010, the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020. [ABSTRACT FROM AUTHOR]

The growth of vegetation directly maintains the ecological security of coal mining areas. It is of great significance to monitor the dynamic changes in vegetation in mining areas and study the driving factors of vegetation spatial division. This study focuses on the Yima mining area in Henan Province. Utilizing MODIS and multi-dimensional explanatory variable data, the Theil–Sen Median + Mann–Kendall trend analysis, variation index, Hurst index, and optimal-parameter-based geographical detector model (OPGD) are employed to analyze the spatiotemporal changes and future trends in the EVI (enhanced vegetation index) from 2000 to 2020. This study further investigates the underlying factors that contribute to the spatial variation in vegetation. The results indicate the following: (1) During the period studied, the Yima mining area was primarily characterized by a moderate-to-low vegetation cover. The area exhibited significant spatial variation, with a notable pattern of "western improvement and eastern degradation". This pattern indicated that the areas that experienced improvement greatly outnumbered the areas that underwent degradation. Moreover, there was an inclination towards a deterioration in vegetation in the future. (2) Based on the optimal parameter geographic detector, it was found that 2 km was the optimal spatial scale for the analysis of the driving factors of vegetation change in this area. The optimal parameter combination was determined by employing five spatial data discretization methods and selecting an interval classification range of 5–10. This approach effectively addresses the subjective bias in spatial scales and data discretization, leading to enhanced accuracy in vegetation change analysis and the identification of its driving factors. (3) The spatial heterogeneity of vegetation is influenced by various factors, such as topography, socio-economic conditions, climate, etc. Among these factors, population density and mean annual temperature were the primary driving forces in the study area, with Q > 0.29 and elevation being the strongest explanatory factor (Q = 0.326). The interaction between temperature and night light was the most powerful explanation (Q = 0.541), and the average Q value of the interaction between the average annual temperature and other driving factors was 0.478, which was the strongest cofactor among the interactions. The interactions between any two factors enhanced their impact on the vegetation's spatial changes, and each driving factor had its suitable range for affecting vegetative growth within this region. This research provides scientific support for conserving vegetation and restoring the ecological system. [ABSTRACT FROM AUTHOR]

In this study, the spatiotemporal variation in carbon stocks under different vegetation coverages during the period 2001-2020 in Henan Province, China, was evaluated using the InVEST, PLUS, and geodetector models. The vegetation coverage patterns and corresponding carbon stocks were predicted under the three scenarios of natural trend, ecological degradation, and ecological restoration, the results show that: (1) Henan Province's vegetation area has been trending downward over the last 20 years, with losses in grassland, savanna, and farming vegetation. (2) The carbon stocks exhibited a low distribution pattern in the central and eastern parts of the country and a high distribution pattern in the northwest and southeast. The growth of total carbon stocks slowed. (3) The overall carbon stores exhibited a declining pattern throughout the three ecological scenarios. The carbon stocks experienced the least decline under the ecological restoration scenario. (4) Evapotranspiration, altitude, slope, distance from farmland and temperature were the main factors affecting the spatial differentiation of regional carbon stocks. Our results can aid in the sustainable management of ecosystems in Henan Province and provides a scientific basis and research concepts for the effective increase in carbon stocks. [ABSTRACT FROM AUTHOR]

The spatiotemporal evolution of vegetation and its influencing factors is crucial for understanding the relationship between vegetation and climate change, which helps guide the management of regional ecosystems effectively. Utilizing the Fractional Vegetation Cover (FVC) data and various meteorological elements from 1982 to 2021, this research employed methodologies, such as grey relational analysis, path analysis, and the time-lag effect, to examine the impact of climate change on FVC fluctuations. It introduced a comprehensive qualitative and quantitative analysis of the multi-factor climate–vegetation relationship, enhancing the understanding of the interaction between the climate and vegetation growth. The findings indicate that 77.41% of the wetland vegetation cover in the Yellow River Basin (YRB) has significantly decreased. Precipitation and evapotranspiration emerged as the primary factors affecting FVC, with soil moisture and temperature having a lesser impact. Given the crucial influence of climate factors' time lag on vegetation dynamics, especially the notable cumulative lag effects observed in arid regions, such as precipitation accumulating over approximately 1.963 months (on average) and evapotranspiration lagging by about 1.727 months (on average), this study offers valuable theoretical insights on vegetation restoration efforts amidst the challenges posed by climate change. [ABSTRACT FROM AUTHOR]

【Objective】The study aimed to explore the response mechanisms of vegetation dynamics in the Beijing-Tianjin-Hebei region to climate factors for a deeper understanding of the causes behind these alterations. It also serves as scientific evidence for guiding ecological restoration efforts in the region.【Method】Trends analysis, partial correlation analysis, machine learning techniques, and explainable method were employed to examine the spatiotemporal changes in the kernel normalized difference vegetation index （kNDVI） in the Beijing-Tianjin-Hebei region from 2000 to 2020, as well as to investigate the differential responses of kNDVI within the region and across different land use types to precipitation and temperature. 【Result】 The findings indicated an improving trend for the kNDVI in the Beijing-Tianjin-Hebei region, with a growth rate of 0.025 per decade. The northwest region exhibited more significant improvement, particularly in forests, which accounted for approximately 17% of the total area. The kNDVI of grasslands showed the fastest growth rate, increasing by 0.061 per decade. The surrounding areas of the southeastern cities were obviously degraded, and the cultivated land kNDVI changed frequently, showing more improvement. The correlation between kNDVI and temperature and precipitation displayed a marked positive trend, with a negative correlation found only around the southern cities. The multi-year SHAP value of precipitation was 0.028, and the multi-year SHAP value of temperature was 0.016, both of which had a positive impact on kNDVI in the Beijing-Tianjin-Hebei region. The overall impact of precipitation on kNDVI was stronger than that of temperature. The kNDVI response of Beijing-Hebei-Tianjin to climate was characterized by regional disparities. The kNDVI of the cultivated land in the southeast plain region and the forest and grassland in the northwest mountain region were significantly promoted by precipitation. In contrast, the kNDVI of the sparse vegetation areas around the cities and Zhangjiakou was negatively affected by precipitation. For the northwest woodland and grassland kNDVI, the promotion of temperature was stronger than precipitation. Temperature had a certain negative impact on the cultivated land kNDVI located in the southern plain, while the urban and rural areas, industrial and mining areas, and residential land kNDVI were most negatively affected by temperature. 【Conclusion】Vegetation change in the Beijing-Tianjin-Hebei region showed a stronger positive response to precipitation, with distinct regional spatial differences in the kNDVI response to climate factors for various land use types. [ABSTRACT FROM AUTHOR]

Aim: How the ability of plants to move towards newly favourable habitats (dispersal limitation) impacts the change of biome distribution and transition under fast climate warming is still debated. Analysing vegetation change in the past may help to clarify the relative importance of underlying ecological processes such as climate, biotic interactions, and dispersal. In this study, we investigated how dispersal limitation affected the distribution of European forests in the last 18,000 years. Location: Southern and Central Europe. Taxon: Spermatophyta. Methods: Using the LPJ‐GM 2.0 model (an extension of LPJ‐GUESS), we simulated European vegetation from the end of the Last Glacial Maximum (18.5 ka) to the current time (0 ka). Using biome reconstructions from pollen data as reference, we compared the performance of two dispersal modes: with no migration constraints or seed limitation (free dispersal mode), and with plant establishment depending on seed dynamics and dispersal (dispersal limitation mode). Results: The model run, including migration processes, was better at capturing the post‐glacial expansion of European temperate forests (and the longer persistence of boreal forests) than the setting assuming free dispersal, especially during periods of rapid warming. This suggests that a number of (temperate) tree taxa experienced delayed occupancy of climatically suitable habitats due to a limited dispersal capacity, i.e., post‐glacial migration lags. Main Conclusions: Our results show that including migration processes in model simulations allows for more realistic reconstructions of forest patterns under rapid climate change, with consequences for future projections of carbon sequestration and climate reconstructions with vegetation feedback, assisted migration and forest conservation. [ABSTRACT FROM AUTHOR]

The impact of changing climate on vegetation in dryland is a prominent focus of global research. As a typical arid region in the world, Central Asia is an ideal area for studying the associations between climate and arid-area vegetation. Utilizing data from the European Centre for Medium-Range Weather Forecasts fifth-generation reanalysis (ECMWF ERA-5) and normalized difference vegetation index (NDVI) datasets, this study investigates the spatio-temporal variation characteristics of the NDVI in Central Asia. It quantitatively assesses the contribution rates of climatic factors to vegetation changes and elucidates the impact of an increased vapor pressure deficit (VPD) on vegetation changes in Central Asia. The results indicate that the growing seasons' NDVI exhibited a substantial increase in Central Asia during 1982–2015. Specifically, there was a pronounced "greening" process (0.012/10 yr, p < 0.05) from 1982 to 1998. However, an insignificant "browning" trend was observed after 1998. Spatially, the vegetation NDVI in the growing seasons exhibited a pattern of "greening in the east and browning in the west" of Central Asia. During spring, the dominant theme was the "greening" of vegetation NDVI, although there was noticeable "browning" observed in southwest region of Central Asia. During summer, the "browning" of vegetation NDVI further expanded eastward and impacted the entire western Central Asia in autumn. According to the estimated results computed via the partial differential equation method, the "browning" trend of vegetation NDVI during the growing seasons was guided by increased VPD and decreased rainfall in western Central Asia. Specifically, the increased VPD contributed 52.3% to the observed vegetation NDVI. Atmospheric drought depicted by the increase in VPD significantly lowers the "greening" trend of vegetation NDVI in arid regions, which further aggravates the "browning" trend of vegetation NDVI. [ABSTRACT FROM AUTHOR]

Water-carbon relationships have been widely recognized in previous studies but rarely included in the Budyko framework. This study improves the Budyko-Fu model by considering the relationship of the underlying surface parameter with vegetation dynamics. Then the evapotranspiration (ET) was estimated using the improved Budyko model and the main driving factors of ET change were identified. The results show that the improved Budyko model considering the gross primary production in the equation could capture the annual ET changes quite well. ET tends to increase with an increase rate of 6.89 mm/a in the study area. Vegetation changes is the most important factor influencing the ET changes contributing 69.87 %, while climate changes in precipitation and potential evapotranspiration contribute 31.23 % and −1.10 % respectively. The main contributors to the estimated ET change differed in the subregion. With vegetation changes being the dominant factor for ET change in the southwestern part, while ET increase was mainly due to the increase in precipitation in the northeastern part of the study area. The contribution of vegetation to the estimated ET change shows a spatially increasing trend from northeast to southwest, while the contribution of precipitation shows a decreasing trend from northeast to southwest. This study proposed a new method for the estimation of ET changes based on the water-carbon coupling relationships and highlight the different contributions of vegetation dynamics to ET changes.

Global temperatures will continue to increase in the future. The ∼640,000-km2 Loess Plateau (LP) is a typical arid and semi-arid region in China. Similar regions cover ∼41% of the Earth, and its soils are some of the most severely eroded anywhere in the world. It is very important to understand the vegetation change and its ecological threshold under climate change on the LP for the sustainable development in the Yellow River Basin. However, little is known about how vegetation on the LP will respond to climate change and what is the sustainable threshold level of vegetation cover on the LP. Here we show that the temperature on the LP has risen 0.27 °C per decade over the past 50 years, a rate that is 30% higher than the average warming rate across China. During historical times, vegetation change was regulated by environmental factors and anthropogenic activities. Vegetation coverage was about 53% on the LP from the Xia Dynasty to the Spring and Autumn and Warring States period. Over the past 70 years, however, the environment has gradually improved and the vegetation cover had increased to ∼65% by 2021. We forecast future changes of vegetation cover on the LP in 2030s, in 2050s and in 2070s using SDM (Species Distribution Model) under Low-emission scenarios, Medium-emission scenarios and High-emission scenarios. An average value of vegetation cover under the three emission scenarios will be 64.67%, 62.70% and 61.47%, respectively. According to the historical record and SDM forecasts, the threshold level of vegetation cover on the LP is estimated to be 53–65%. Currently, vegetation cover on the LP has increased to the upper limit of the threshold value (∼65%). We conclude that the risk of ecosystem collapse on the LP will increase with further temperature increases once the vegetated area and density exceed the threshold value. It is urgent to adopt sustainable strategies such as stopping expanding vegetation area and scientifically optimizing the vegetation structure on the LP to improve the ecological sustainability of the Yellow River Basin.

Drainage is the most important single factor affecting mires globally but its effects vary depending on drainage type, climate and wetland ecosystem. Sixteen transects in fifteen drained raised bogs in the hemiboreal zone of Estonia were examined to determine the spatial effects of drainage on vegetation and environmental factors. We found that the effects of drainage along a hydrosequence depended on the drainage type; i.e., whether it took the form of a cutoff ditch intercepting surface and subsurface water flow around the perimeter of the bog massif, or the drainage ditch crossed the central part of the bog. Some drains of the latter type were still functioning whereas old hand-dug examples seemed to be derelict and inactive. For both of the active drainage types, maximum water levels stabilised within 25 m of the ditch but drawdown effects on minimum and average water levels extended to 450 m. The vegetation variables that were most sensitive to drainage were the number and the percentage of bog-specific species, the number of ground vegetation species, the total cover of Sphagnum species, and the height and canopy cover of trees. Trees were rare when the minimum water level was higher than -20 cm, and the number of bog-specific species increased rapidly as the minimum water level rose towards the surface from -90 cm. Total cover of the shrub layer decreased and total cover of Sphagnum species increased almost linearly with a rise of minimum water level up to 40 cm, whereas the total cover of field layer species stabilised when the minimum water level was at -100 cm. Total cover of Sphagnum species in the field layer increased over distances of up to 250–300 m from the drainage ditch and the percentage of bog-specific and fen-specific species stabilised 190–300 m from the ditches.

As an ecologically sensitive area with significant desertification problems, the Ring-Tarim Basin has a fragile ecological environment that is vulnerable to both natural and anthropogenic factors. Accurate long-term vegetation observations are ecologically, socially, and economically important for desertification control. In this study, based on the ground-measured data and the fractional vegetation cover (FVC) inversion dataset obtained by the image element dichotomy method, we used the methods of slope-trend analysis and multiple-regression residual analysis to analyze the spatial and temporal characteristics of the vegetation cover in the desertified area of the Ring-Tarim Basin. At the same time, we assessed the impacts of climate change and human activities on vegetation changes and the contribution of driving forces. The results showed that (1) The annual mean value of FVC in the growing season in the Ring-Tarim Basin generally showed a fluctuating and increasing trend during the period of 1993–2021; a decreasing trend during 1993–1999, with a change rate of −0.13 × 10−2a−1; and the fastest increasing trend during 2010–2021, with a change rate of 0.23 × 10−2a−1. (2) The effects of climate change and human activities on FVC changes in the growing season had great spatial heterogeneity. The areas where climate change and human activities had no significant effect on FVC changes in the growing season accounted for 86.25% and 77.91%, respectively, the areas where climate and human activities promoted FVC increase in the growing season accounted for 10.53% and 16.37%, respectively, and the areas where climate and human activities inhibited FVC increase in the growing season accounted for 3.22% and 5.72%, respectively. (3) About 76.9% of the FVC changes in the area around the Ring-Tarim Basin were caused by climate change and human activities. In addition to the eastern part of the study area, the vegetation cover of the oases in the west, north, and south generally showed an increasing trend, and the increasing area was proportional to the distribution density of the oasis cities. The trend of vegetation change in the area of the oasis and the fringes of the oasis was drastic. The contribution and inhibition of human activities to FVC, and the driving force of FVC change were greater than that of climate change. More than half of the area had an anthropogenic contribution of more than 60%, indicating that China's ecological projects have had a significant effect on vegetation change in the extreme arid regions. [ABSTRACT FROM AUTHOR]

The changing climate and intensifying human activities have made an impact on the hydrological processes in the upper Yangtze River (UYR), but quantifying their effects remains uncertain. This study used the Budyko framework to investigate the response of runoff (Q) to climate change and human activities during 1956–2017 and evaluate the impacts of human activities, including land use/cover change, water use, dam construction, and vegetation change, on watershed characteristic. Results show that climate change is the dominant driver of Q variations in the Wujiang River (WJR), Jialing River (JLR), and Jinsha River (JSR) watersheds, with contributions of 58.6%, 66.9%, and 67.6%, respectively. However, in Mingjiang River (MJR) and UYR watersheds, human activities contribute more to Q variations with 55.2% and 51.2%, respectively. Human activities play important roles in variation of watershed characteristics, and they can explain 22%, 26%, 36%, 25%, and 53% of the watershed character change in UYR, WJR, JLR, MJR, and JSR, respectively. This study conducts a comprehensive analysis of the causes of Q change in UYR, and provides a new perspective to explore the effects of specific human activities on watershed characteristics. Plain Language Summary: With climate change and intensifying human activities, the water cycle has been changed. Runoff is an essential component of the water cycle, and its response to changing environments has drawn broad attention. This study aims to quantify the contributions of climate change and human activities to runoff changes in the upper Yangtze River (UYR) and its four sub‐watersheds over the past half‐century. According to the results, human activities and climate change have been responsible for approximately 51.2% and 48.8% of the observed runoff changes in UYR, respectively. It suggests that both human activities and climate change have played significant roles, and their contributions are remarkably comparable. In addition, the impacts of human activities on watershed environment changes are analyzed. The results suggest that increased settlement area and industrial water use are the dominant influencing factors. Key Points: Human activities and climate change have made comparable contributions to the runoff reduction in the upper Yangtze RiverWater use, land use/cover change, vegetation change, and dam construction together explain 22% of the watershed environment changesHuman settlements and increased industrial water use have been the principal factors contributing to the changes in watershed environment [ABSTRACT FROM AUTHOR]

Background: Vegetation is one of the main components of biosphere preservation that acts as a link between soil, water, and atmosphere . It is crucial in providing organic matter, regulating the carbon cycle, and exchanging energy on the surface of the earth. In recent years, climate change and global warming have caused frequent events, such as floods, heat waves, and droughts, which can damage terrestrial ecosystems. Climate change directly affect s the growth of vegetation; on the other hand, changes in vegetation cover give feedback to climate change by regulating water, energy exchange, and carbon dioxide concentration. Methods: The research was carried out in Mazandaran province to analyze vegetation trend in the study area during the 2001 -2020 period. The 16 -day composite MODIS -NDVI time series data, named MOD13Q1, with a spatial resolution of 250 meters (920 NDVI images) were used for this purpose. The non -parametric Mann -Kendall method was employed to investigate changes in vegetation activity and trend significance. The overlying vegetation trend map and the location of big cities and main roads of the province were also investigated in this research . Results: A decreasing trend of vegetation cover was observed in 16% of the total studied area, and the rest showed an increasing trend, although the significant decrease and increase of vegetation cover occurred in 5% and 65% of the area, respectively, with a 95% confidence level. The vegetation trend map showed that the most significant reduction of vegetation in the last 20 years occurred in coastal areas and low -altitude regions, especially around big cities and main roads entering the province. Decrease d vegetation around the metropolises is expected due to the increase in population and the need for urban development. However, the results showed that the most significant decrease in vegetation occurred in the cities of Mahmudabad (19%), Babolsar (17%), Ghaemshahr (10%), and Jouybar (9%) . Unlike the big cities of Sari and Ghaemshahr, the cities of Sorkhrood, Mahmudabad, and Babolsar are at the top of the cities with reduction s in vegetation cover in the last 20 years . Unfortunately, this is not due to urban development and increasing population, but drastic changes in the use of agricultural land and citrus orchards and turning them into private villas are the main factor in the reduction of vegetation. Comparing the vegetation trend map with the main roads of the province reveals that a significant reduction of vegetation has occurred around the main roads entering Mazandaran province, especially on the Haraz, Firouzko u h, and Farim road s. In contrast, smaller area s of vegetation cover reduction were observed around the Chalus road. The investigation of the areas with positive vegetation cover trends showed that the highlands of the province, especially the eastern highlands, experienced a significant increase in vegetation cover. However, a less significant positive trend of vegetation was observed in the western highlands. Rather, most of these areas have experienced no trend conditions in the past 20 years, which could be due to the recent global warming and the higher temperature in the east of the province than in the western regions, which generally has caused suitable temperature conditions for the growth of vegetation in the eastern highlands of the province. It seems that the western highlands still do not have suitable temperature conditions for the growth of vegetation. Conclusion: The results of this research show that the changes in vegetation in Mazandaran province are under the control of two natural and human factors, and the former (climate) has caused an increase in vegetation in 65% of the area of the province, especially in the highland s, probably caused by the increase in temperature. The recent global warming has made it possible to provide living conditions for plants in the highlands of the province, especially the eastern highlands . Nevertheless, the human factor has been destroying vegetation throughout the province, especially in tourist areas and those with easy access. As such, a significant trend of vegetation reduction was observed both on the coasts, around metropolises, in the heart of the Hyrkan forests, and in the heights near the main roads. A significant decrease in vegetation cover has occurred in 5% of the area of the province, and these decreases were observed mostly in the plains, coastal strip, low altitudes with low slopes, outskirts of cities, and roads of the studied area. Vegetation is also being destroyed in the marginal areas of the roads from Ramsar to the neighboring western province, Gorgan Sari, Tehran, Chalus, H araz, and Firuzko uh, which can be the main reason for the increase in traffic load, changes in land use, and the construction of recreational facilities and villas. Based on the results of this research, extreme changes in land use in the last 20 years are very evident, and if the human process of land use change continues along with the loss of water and soil resources, we may see irreparable blows to the ecosystem of the Caspian systems in the near future. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to examine the influence of forest vegetation changes on water-sediment dynamics, and to provide a scientific basis for formulating and adjusting ecological environment development policies in the Yellow River Basin. [Methods] Based on the runoff and sediment discharge data from the Dacun hydrological station in the Shiwangchuan River Basin from 1959 to 2018, as well as precipitation data within the basin, the hydrological changes over a span of 60 years were analyzed. By combining NDVI data from 1985 to 2018 and land use data from five periods, the vegetation underlying surface driving effects on water-sediment changes in the watershed were analyzed and discussed. [Results] The runoff and sediment discharge in the Shiwangchuan River Basin had shown a significant decreasing trend over the past 60 years（p＜0.01）, with abrupt changes occurring in 1988 and 1983, respectively. However, there had been no significant trends in land use and precipitation within the watershed during this period. The NDVI during the growing season showed little variation before 2000 but exhibited a significant increasing trend after 2000. [Conclusion] Before 2000, the implementation of various soil and water conservation measures was the main reason for the decrease of runoff and sediment transport in the basin; After entering the 21st century, the improvement of vegetation quality in the basin has further reduced runoff and sediment transport. [ABSTRACT FROM AUTHOR]

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Partitioning soil water balance (SWB) is an effective approach for deciphering the impacts of vegetation change on soil hydrological processes. Growing apple trees on the Loess Plateau, China, leads to a substantial deep soil water deficit, posing a serious threat to the sustainable development of apple production. However, the impact of deep-rooted apple trees on SWB remains poorly understood. In this study, we conducted a "Paired Plot" experiment to achieve this objective by decoupling SWB components using water stable isotopes, tritium, and soil water contents from deep soil cores (up to 25 m) under apple orchards with a stand age gradient of 8–23 years. The results showed that deep soil water storage under apple orchards was notably reduced compared to nearby farmland, showing a stand age-related pattern of deep soil water deficit (R2 = 0.91). By analyzing the changing patterns of SWB components, we found that the main factor driving this deficit is the water uptake process controlled by the deep root system. This process is triggered by the increased transpiration demand of apple trees and short-term water scarcity. These findings have implications for understanding soil water dynamics, sustainable agroforestry management, and soil water resources' protection in this region and other similar water-limited areas. [ABSTRACT FROM AUTHOR]

Question: Changes caused by climate warming and nitrogen pollution are observed in forest, grassland and alpine ecosystems worldwide. However, still little is known about the impact of these globally influencing factors on natural rocky plant communities. Has species composition of natural rocky communities changed over time? What is the role of large‐scale and fine‐scale environmental factors in shaping the compositional, functional and habitat patterns in studied plant communities over time? Location: Sudetes Mountains, southwestern Poland. Methods: We used 214 pairs of replots (collected between 1989 and 2022) of rocky plant communities, with a mean timespan of 14.2 years. The changes in species composition, environmental conditions and functional traits were analysed using ordination techniques and generalised additive models (GAMs) and with reference to large‐scale factors (mean maximum temperatures, actual evapotranspiration, N deposition) and fine‐scale factors (light availability, bedrock type, initial site conditions) for each locality. Results: Species composition of the studied communities has not changed significantly over time. Only for 11 out of 258 species, statistically significant increases (from 2% to 8%) in their proportion were recorded. The changes in environmental conditions were significantly influenced mainly by fine‐scale factors such as changes in light availability and baseline site conditions. Plots that were initially less thermophilic or nitrophilic showed stronger signals of thermophilisation and eutrophication in the resurvey. The influence of large‐scale factors was considerably less pronounced. Similarly, the key role in explaining changes in plant traits for the data set under study falls to local factors, particularly changes in light availability. Conclusions: Our study confirms the validity of considering both large‐ and fine‐scale factors as well as initial site conditions in research on long‐term changes in plant communities. Rocky plant communities respond to global changes in a different way than other types of phytocoenose, showing high stability of species composition and functional traits over time. [ABSTRACT FROM AUTHOR]

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The directional ecological filtering hypothesis posits that species in high-altitude environments typically exhibit broad environmental tolerance, influencing the colonization success of non-native species through niche overlap with natives. This study examines this hypothesis on Changbai Mountain, focusing on the encroachment of the herb Deyeuxia angustifolia from mountain birch forests into alpine tundra, where it competes with the endemic Rhododendron aureum. We established a permanent plot containing 10,000 continuous quadrats (2 × 2 m) in the summer of 2014, covering from treeline to the upper limit of alpine tundra. Each quadrat was divided into 40 × 40 cm resolution cells, totaling 250,000 cells. In 2014 we photographed and manually interpreted tundra plant species for all cells, assessing topographic and edaphic niche characteristics (the range of the factors) for both species. Findings reveal: (1) Over 50 % niche overlap between D. angustifolia and R. aureum, suggesting intense competition; (2) Broader niche width for R. aureum compared to D. angustifolia; and (3) The expansion of D. angustifolia is facilitated by available nitrogen, while R. aureum is uniquely adapted to low phosphorus levels at higher altitudes. These results demonstrate that ecological and environmental filtering jointly shape distribution patterns of R. aureum and D. angustifolia, supporting the idea that environmental filtering is critical in the colonization of invading plant species. Our research sheds light on the pivotal roles played by microenvironmental factors, notably topography and soil, in determining the composition and distribution of plant communities, and contributes valuable insights for understanding and forecasting future shifts in plant composition of alpine tundra.

Nowadays, atmospheric concentrations of nitrogen oxides (NOX) have increased rapidly and exceeded the threshold of ecosystems, inevitably affecting the plant growth and community stability, especially in urban green space. The increase of atmospheric NOX is also accompanied by natural and anthropogenic environmental change, which also bring severe environmental stresses on green vegetation. To better understand drivers that contribute to the vegetation changes, this study explored the interaction among atmospheric NOX, climate, terrain, and urbanization, and its impact on the tree leaf and forest community traits, using a dataset with 118 plots of tree communities composed of 5781 trees across distinct types of urban green space in Tianjin, a highly urbanized metropolis in China. The results indicated that atmospheric NOX concentration showed a positive association with urbanization and temperature, which co-limited the tree growth and resulted in the vegetation browning of urban green space. The responses of coniferous and broadleaved forests were different, whose understory herbaceous diversity and height had contrary tendencies to environmental change. Meanwhile, urbanization intensified atmospheric N deposition and heat island effect, increasing the leaf chlorophyll contents of tree species in urban green spaces. While leaf herbivory showed positive correlation with urbanization, temperature, and evaporation only in the high NOX regime. Overall, this study found that atmospheric NOX could be used as a good indicator of urbanization. These findings also advanced our recognition of the environmental driving factors of green vegetation dynamics, and provided references for the research of elsewhere.

Information on vegetation dynamics is important for agricultural and ecological management. However, a systematic framework for the study of vegetation dynamics is still lacking. Therefore, this study developed the Vegetation Dynamic Change And Land Cover (VDCALC) framework to achieve a comprehensive analysis of vegetation dynamic change. The framework uses the Normalized Difference Vegetation Index (NDVI) data derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Global Inventory Modeling and Mapping Studies (GIMMS), along with land cover data as input. It combines several models, including the Theil-Sen median, Mann-Kendall test and coefficient of variation, which can qualitatively and quantitatively study the spatiotemporal dynamic change of vegetation, and Hurst exponent model, which was used to predict the future change. Meteorological and statistical data were used as auxiliary data in this framework to analyze the influencing factors of vegetation change. Results showed that the degradation area was mainly concentrated in the coastal areas of the peninsula, Rizhao, Weifang, Linyi and Zibo during the period from 2001 to 2015, accounting for 36.05%. Based on annual-scale data, the NDVI showed an overall improvement trend, with significant increases in spring and autumn. However, predictions indicated that the degraded area would account for 37.18% in the future. In addition, meteorological factors were found to influence vegetation growth differently depending on the season. This study demonstrated a complete and reliable framework for effectively reflecting regional vegetation changes. It is recommended for application in large-scale areas to guide agricultural and ecological management.

Abstract The eastern part of the Benoue River bank is undergoing degradation marked by a significant decrease in vegetation cover and woody resources due to anthropogenic activities and climatic. The main objective of this study is to analyze the farmers’ knowledge of vegetation evolution and the dynamics of land use using satellite images in the east of the bank of the Benoue. The methodological approach used is an integrated one combining field surveys, remote sensing, mapping, and modeling. The results obtained show that 88% of the population surveyed believe that the area covered by vegetation has decreased. The reasons for this decrease are numerous, but the main one remains the strong anthropic activity that would be at the origin of the progressive degradation of the land. The evolutionary trend of plant formations is essentially regressive for natural formations from 1991 to 2021. The analysis of the evolution of land use showed that in the Rey-Bouba district during 1991, 58.24% of the area formerly made up of dense woody formations regressed considerably to 25.77% in 2021. The same is true for the Bibemi district where the area of wooded zone has decreased from 65.47% in 1991 to 28.45% of the total area in 2021. This regression of the surface area of wooded formations was done to the benefit of anthropized occupation classes whose area has increased. They suggest an effective awareness in the monitoring of the dynamics of the vegetation cover subjected to anthropic pressures and climatic variations for a better-integrated management of the vegetation of this area.

[Objective] Intensive research on the spatial and temporal response characteristics of meteorological drought to vegetation at different time scales in the Yellow River Basin provides valuable information for ecological conservation, water resource management, and climate change adaptation, and can mitigate the environmental and economic problems caused by drought. [Methods] Based on the standardized precipitation evapotranspiration index (SPEI) and normalized vegetation index (NDVI) for the Yellow River Basin during the period of 1982—2020, image-by-image metric linear regression models, Sen’s trend analysis and Mann-Kendall test were used to study the spatial and temporal distribution characteristics of meteorological droughts at different time scales in the Yellow River Basin, as well as their impacts on vegetation. [Results] (1) From 1982 to 2020, the Yellow River Basin showed an insignificant increasing trend in aridity, with regions exhibiting negative trends in SPEI mainly concentrated in the western region from Longyangxia to Lanzhou, the southern part of the Yellow River Basin, and the surrounding areas of the Hetao Plain. (2) The spatial distribution pattern of average vegetation coverage in the Yellow River Basin demonstrated a decreasing trend from south to north and from southeast to northwest. The proportion of regions with a significant increase in vegetation coverage (61.94%) was greater than that of those with a significant decrease (5.43%). (3) In most areas of the Yellow River Basin, drought conditions were positively correlated with vegetation status. Regions exhibiting significant positive correlations were mainly concentrated in the northwest and northernmost areas of the Yellow River Basin, indicating that vegetation in these areas was severely affected by drought. (4) Grassland and cultivated land showed the strongest response to drought at a six-month time scale, while forests and unused land were more vulnerable to long-term drought compared to other land types. All four landform types were susceptible to medium- to long-term water shortages, with vegetation in hilly areas being the most affected by drought. [Conclusion] The results of the study provide an effective scientific basis for disaster prevention and mitigation as well as ecological environment construction in the Yellow River Basin, and provide important information for ecological protection, water resource management and climate change adaptation in the Yellow River Basin, which will help to formulate more precise policies and measures to mitigate the potential impacts of drought on the environment and the economy, and to promote sustainable development.

[Objective] The Yellow River Basin is an important ecological protection barrier in China, but its ecological environment is fragile. Studying the relationship between vegetation changes and water production services in the Yellow River Basin provides guarantees for its ecological construction and high-quality development. [Methods] Based on NDVI data and InVEST model, trend analysis and correlation analysis methods were used to combine vegetation change with water supply services. The temporal and spatial characteristics of NDVI and water production services in the Yellow River Basin from 2001 to 2020 were analyzed, and the trend changes and interrelationships between NDVI and water production services were studied. [Results] (1) The NDVI and water production depth of the Yellow River basin showed an increasing trend, with the growth rate of 0.05/10 a and 18.215 mm/10 a respectively. The NDVI was mainly showing a significant increase, while the water production depth was mainly showing an insignificant increase. In addition, the water production in the basin was also continuously increasing. (2) NDVI was closely related to water production depth, and there was a significant positive correlation between the two in terms of time, with a correlation coefficient of 0.75 (p

Arctic and boreal permafrost soil organic carbon (SOC) decomposition has been slower than carbon inputs from plant growth since the last glaciation. Anthropogenic climate warming has threatened this historical trend by accelerating SOC decomposition and altering wildfire regimes. We accurately modeled observed plant biomass and carbon emissions from wildfires in Alaskan ecosystems under current climate conditions. In projections to 2300 under the RCP8.5 climate scenario, we found that warming and increased atmospheric CO2 will result in plant biomass gains and higher litterfall. However, increased carbon losses from (a) wildfire combustion and (b) rapid SOC decomposition driven by increased deciduous litter production, root exudation, and active layer depth will lead to about 4.4 PgC of soil carbon losses from Alaska by 2300 and most (88%) of these loses will be from the top 1 m of soil. These SOC losses offset plant carbon gains, causing the ecosystem to transition to a net carbon source after 2200. Simulations excluding wildfire increases yielded about a factor of four lower SOC losses by 2300. Our results show that projected wildfire and its direct and indirect effects on plant and soil carbon may accelerate high-latitude soil carbon losses, resulting in a positive feedback to climate change.

Detecting and attributing vegetation variations in the Yellow River Basin (YRB) is vital for adjusting ecological restoration strategies to address the possible threats posed by changing environments. On the basis of the kernel normalized difference vegetation index (kNDVI) and key climate drivers (precipitation (PRE), temperature (TEM), solar radiation (SR), and potential evapotranspiration (PET)) in the basin during the period from 1982 to 2022, we utilized the multivariate statistical approach to analyze the spatiotemporal patterns of vegetation dynamics, identified the key climate variables, and discerned the respective impacts of climate change (CC) and human activities (HA) on these variations. Our analysis revealed a widespread greening trend across 93.1% of the YRB, with 83.2% exhibiting significant increases in kNDVI (p < 0.05). Conversely, 6.9% of vegetated areas displayed a browning trend, particularly concentrated in the alpine and urban areas. With the Hurst index of kNDVI exceeding 0.5 in 97.5% of vegetated areas, the YRB tends to be extensively greened in the future. Climate variability emerges as a pivotal determinant shaping diverse spatial and temporal vegetation patterns, with PRE exerting dominance in 41.9% of vegetated areas, followed by TEM (35.4%), SR (13%), and PET (9.7%). Spatially, increased PRE significantly enhanced vegetation growth in arid zones, while TEM and SR controlled vegetation variations in alpine areas and non-water-limited areas such as irrigation zones. Vegetation dynamics in the YRB were driven by a combination of CC and HA, with relative contributions of 55.8% and 44.2%, respectively, suggesting that long-term CC is the dominant force. Specifically, climate change contributed to the vegetation greening seen in the alpine region and southeastern part of the basin, and human-induced factors benefited vegetation growth on the Loess Plateau (LP) while inhibiting growth in urban and alpine pastoral areas. These findings provide critical insights that inform the formulation and adaptation of ecological conservation strategies in the basin, thereby enhancing resilience to changing environmental conditions. [ABSTRACT FROM AUTHOR]

In the arid southwestern U.S., urban greening strategies have been promoted to alleviate ecosystem disservices associated with lawns, including the adoption of xeric yards with desert-adapted floras and gravel groundcover and wildlife-friendly yards with complex vegetation structure and composition. Scant studies have investigated the extent of different vegetation changes in urban greening practices and the complexity of associated human drivers. We addressed this gap by analyzing survey data from two survey periods (2017 and 2021) to answer the following questions: to what extent have residents from metropolitan Phoenix made different vegetation changes in their yards over the last decade, and how do multi-scalar human drivers affect different vegetation changes? We found a sustainable trajectory for residential vegetation changes in Phoenix since mid-2010s, with declining additions of grass and increases in trees and desert plants across residential neighborhoods. Esthetics was an influential driver of both tree planting and native gardening. Additionally, tree planting was associated with anthropocentric values (i.e., low-maintenance needs), while desert plant additions reflected the appreciation of nature (i.e., attitudes towards the desert) and environmental concerns (i.e., supporting wildlife). Institutions such as local government programs might shape residents' vegetation choices, as tree planting differed among municipalities. We also found counterintuitive influences of residential tenure controls on landscaping decisions. Specifically, renters were more likely to add yard trees compared to homeowners. Our results inform landscape sustainability by identifying potential pathways to residential yard changes that offer a multitude of services while being appreciated and maintained by residents. [ABSTRACT FROM AUTHOR]

Subarctic ecosystems are subjected to increasing nitrogen (N) enrichment and disturbances that induce particularly strong effects on plant communities when occurring in combination. There is little experimental evidence on the longevity of these effects. We applied N-fertilization (40 kg urea-N ha−1 year−1 for 4 years) and disturbance (removal of vegetation and organic soil layer on one occasion) in two plant communities in a subarctic forest-tundra ecotone in northern Finland. Within the first four years, N-fertilization and disturbance increased the share of deciduous dwarf shrubs and graminoids at the expense of evergreen dwarf shrubs. Individual treatments intensified the other's effect resulting in the strongest increase in graminoids under combined N-fertilization and disturbance. The re-analysis of the plant communities 15 years after cessation of N-fertilization showed an even higher share of graminoids. 18 years after disturbance, the total vascular plant abundance was still substantially lower and the share of graminoids higher. At the same point, the plant community composition was the same under disturbance as under combined N-fertilization and disturbance, indicating that multiple perturbations no longer reinforced the other's effect. Yet, complex interactions between N-fertilization and disturbance were still detected in the soil. We found higher organic N under disturbance and lower microbial N under combined N-fertilization and disturbance, which suggests a lower bioavailability of N sources for soil microorganisms. Our findings support that the effects of enhanced nutrients and disturbance on subarctic vegetation persist over decadal timescales. However, they also highlight the complexity of plant–soil interactions that drive subarctic ecosystem responses to multiple perturbations across varying timescales. [ABSTRACT FROM AUTHOR]

Growing season temperatures play a crucial role in controlling treeline elevation at regional to global scales. However, understanding of treeline dynamics in response to long-term changes in temperature is limited. In this study, we analyze pollen, plant macrofossils, and charcoal preserved in organic layers within a 10,400-year-old ice patch and in sediment from a 6000-year-old wetland located above present-day treeline in the Beartooth Mountains, Wyoming, to explore the relationship between Holocene climate variability and shifts in treeline elevation. Pollen data indicate a lower-than-present treeline between 9000 and 6200 cal yr BP during the warm, dry summer and cold winter conditions of the early Holocene. Increases in arboreal pollen at 6200 cal yr BP suggest an upslope treeline expansion when summers became cooler and wetter. A possible hiatus in the wetland record at ca. 4200–3000 cal yr BP suggests increased snow and ice cover at high elevations and a lowering of treeline. Treeline position continued to fluctuate with growing season warming and cooling during the late-Holocene. Periods of high fire activity correspond with times of increased woody cover at high elevations. The two records indicate that climate was an important driver of vegetation and treeline change during the Holocene. Early Holocene treeline was governed by moisture limitations, whereas late-Holocene treeline was sensitive to increases in growing season temperatures. Climate projections for the region suggest warmer temperatures could decrease effective growing season moisture at high elevations resulting in a reduction of treeline elevation. [ABSTRACT FROM AUTHOR]

The rapid urbanization observed in various regions worldwide has led to the transformation of agricultural, forest, and green spaces into grey areas. The expansion of these grey areas contributes to heat wave events and an overall increase of average temperatures in specific regions due to their high reflectance properties. This study focuses on analyzing the heat island phenomenon resulting from urban growth and vegetation change over the past 30 years (1990–2020) in three key districts, namely Sheikhupura, Chiniot, and Pakpattan, located in the Punjab province. Landsat data is utilized to assess the urban heat island (UHI) effect caused by land cover changes in these regions. The maximum likelihood classification method is employed to classify remote sensing data, enabling the identification of heat islands based on surface emissivity. The UHI has main influence on built-up land areas therefore, to forecast future scenarios of LULC and their impact on LST, the study employs cellular automata (CA) modeling and incorporates several spatial variables to predict LULC for the year 2050. Four primary land cover classes, namely vegetation including cropland, built-up, water, and barren land, are utilized to examine temperature differences across different land cover types, aiming to understand the impact of land cover changes on temperature patterns. The findings also indicate that barren land and urban areas exhibit the highest thermal reflectivity, contributing significantly to increased surface temperatures. Over the past three decades, the surface temperature has risen by 1.65 °C in Chiniot, 0.86 °C in Sheikhupura, and experienced a slight decrease of – 0.04 °C in Pakpattan. The temperature decrease in Pakpattan can be attributed to a substantial reduction in barren land, which has been converted into agricultural and urban areas. This indicates a negative correlation between land surface temperature (LST) and vegetation cover. The changes in land use and land cover (LULC) in the study area are found to be relatively insignificant. [ABSTRACT FROM AUTHOR]

Kentucky is one of the largest coal-producing states; surface coal mining has led to changes in natural land cover, soil loss, and water quality. This study explored relationships between actively mined and reclaimed areas, vegetation change, and water quality parameters. The study site evaluated 58 watersheds with Landsat-derived variables (reclamation age and percentage of mining, reclaimed forest, and reclaimed woods) as well as topographic variables (such as elevation, slope, drainage density, and infiltration). Water samples were collected in spring (n = 9), summer (n = 14), and fall (n = 58) 2017 to study changes in water quality variables (SO42−, alkalinity, conductivity, Ca2+, Mg2+, Mn2+, Al3+, and Fe2+, Fe3+) in response to changes in land cover. Pearson correlation analyses indicated that conductivity has strong to very strong relationships with water quality variables related to coal mining (except Al3+, Fe2+, Fe3+, Mn2+, elevation, slope, and drainage density) and land cover variables. In addition, separate regression analyses were performed, with conductivity values based on samples collected in the fall. First, conductivity responses to mining percentage, reclamation age and topographic variables were examined (adjusted R2 = 0.818, p < 0.01). Next, vegetation cover change parameters were added to the same model, which yielded slightly improved R2 (adjusted R2 = 0.826, p < 0.01). Finally, reclamation age and mining percentages were used to explain the quantity of reclaimed forested areas as a percentage of watersheds. The model was significant (p < 0.01), with an adjusted R2 value of 0.641. Results suggest that the quantity (area as a percentage) of reclaimed forests may be a predictor of the mining percentage and reclamation age. This study indicated that conductivity is a predictable water quality indicator that is highly associated with Coal-Mine-Related Stream Chemistry in areas where agriculture and urban development are limited. Water quality is not suitable for various purposes due to the presence of contaminants, especially in mined sites. These findings may help the scientific community and key state and federal agencies improve their understanding of water quality attributes in watersheds affected by coal mining, as well as refine land reclamation practices more effectively while such practices are in action. [ABSTRACT FROM AUTHOR]

The exchange of moisture and energy between the land and the atmosphere plays a crucial role in terrestrial hydrological cycle and climate change. However, existing studies on the retrieval of surface water and heat flux tend to overlook the dynamic changes in surface vegetation and atmospheric aerosols, which directly affect surface energy and indirectly alter various meteorological factors, including cloud, precipitation, and temperature. In this study, we assess the machine-learning retrieval method for surface fluxes that takes into account vegetation changes and aerosol effects, using FLUXNET observations and remote sensing data to retrieve latent heat flux (LE) and sensible heat flux (H). We constructed four sets of deep neural network models: (a) The first set considers only meteorological factors, (b) the second set considers meteorological factors and aerosols, (c) the third set considers meteorological factors and vegetation changes, and (d) the fourth set comprehensively considers meteorological factors, aerosols, and vegetation changes. All model performances were evaluated using statistical indicators. ERA5 reanalysis and remote sensing data were used to drive the models and retrieve daily H and LE. The retrieved results were validated against ground observation sites that were not involved in model training or the FLUXCOM product. The results show that the model that considers meteorological factors, aerosols, and vegetation changes has the smallest errors and highest correlation for retrieving H and LE (RH = 0.85, RMSEH = 24.88; RLE = 0.88, RMSELE = 22.25). The ability of the four models varies under different vegetation types. In terms of seasons, the models that consider meteorological factors and vegetation changes, as well as those that comprehensively consider meteorological factors, aerosols, and vegetation changes, perform well in retrieving the surface fluxes. As for spatial distribution, when atmospheric aerosols are present in the region, the model that considers both meteorological factors and aerosols retrieves higher values of H compared to the model that considers only meteorological factors, while the LE values are relatively lower. The model that considers meteorological factors and vegetation changes, as well as the model that comprehensively considers meteorological factors, aerosols, and vegetation changes, retrieves lower values in most regions. Through the validation of independent observation sites and FLUXCOM products, we found that the model, considering meteorological factors, aerosols, and vegetation changes, was generally more accurate in the retrieval of surface fluxes. This study contributes to improving the retrieval and future prediction accuracy of surface fluxes in a changing environment. [ABSTRACT FROM AUTHOR]

Sediments of Lake Lubińskie were investigated to track human-induced vegetation and fire activity changes in Lubusz Land (western Poland). Geochemical data, as well as pollen, macrocharcoal, and statistical analyses (CONISS, CharAnalysis, PCA, BINCOR) allowed us to recognize the major phases of the human impact. At the beginning of the investigation period, 3000 years ago, the area had already experienced disturbances from humans caused by the Lusatian and Przeworsk cultures, followed by western Slavs, and modern society. Land cover changes were mostly related to deforestation and gaining arable lands. The forest communities shrank substantially also due to timber demand from the growing society. However, the pollen record shows that within the last ~50 years the area experienced forest regeneration. Wildfires played an important role in shaping the landscape in the area of Lake Lubińskie. Overall, 23 fires were identified within the profile showing relatively high fire frequencies (up to 4.8 fires per 500 years) between 600 −38/+36 BCE and 1 ± 206 CE as well as between 1065 ± 98 CE and 1380 ± 92 CE. The highest fire frequency was observed between the 1000s and mid-1400s, showing decreased fire return interval (FRI) and increased charcoal flux as well as progressive deforestation. These changes were related to the establishment of villages (e.g., Lubin village) and the presence of the Joannites. Fire was most commonly used as a land management tool to gain patches of land for agrarian purposes. PCA and BINOCR analyses suggest that most of the fires were set by humans, but natural causes of ignition cannot be excluded. The land-use changes affected the vegetation in the region, causing increased erosion and shifts in the geochemistry of the lake reflected in better bottom waters ventilation and progressive eutrophication. [ABSTRACT FROM AUTHOR]

The effects of climate change on vegetation composition and distribution are evident in different ecosystems around the world. Although some climate‐derived alterations on vegetation are expected to result in changes in lifeform fractional cover, disentangling the direct effects of climate change from different non‐climate factors, such as land‐use change, is challenging. By applying "Liebig's law of the minimum" in a geospatial context, we determined the climate‐limited potential for tree, shrub, herbaceous, and non‐vegetation fractional cover change for the conterminous United States and compared these potential rates to observed change rates for the period 1986 to 2018. We found that 10% of the land area of the conterminous United States appears to have climate limitations on the change in fractional cover, with a high proportion of these sites located in arid and semiarid ecosystems in the Southwest part of the country. The rates of change in lifeform fractional cover for the remaining area of the country are likely limited by non‐climate factors such as the disturbance regime, land management, land‐use history, soil conditions, and species interactions and adaptations. [ABSTRACT FROM AUTHOR]

Subarctic ecosystems are exposed to elevated temperatures and increased cloudiness in a changing climate with potentially important effects on vegetation structure, composition, and ecosystem functioning. We investigated the individual and combined effects of warming and increased cloudiness on vegetation greenness and cover in mesocosms from two tundra and one palsa mire ecosystems kept under strict environmental control in climate chambers. We also investigated leaf anatomical and biochemical traits of four dominant vascular plant species (Empetrum hermaphroditum, Vaccinium myrtillus, Vaccinium vitis‐idaea, and Rubus chamaemorus). Vegetation greenness increased in response to warming in all sites and in response to increased cloudiness in the tundra sites but without associated increases in vegetation cover or biomass, except that E. hermaphroditum biomass increased under warming. The combined warming and increased cloudiness treatment had an additive effect on vegetation greenness in all sites. It also increased the cover of graminoids and forbs in one of the tundra sites. Warming increased leaf dry mass per area of V. myrtillus and R. chamaemorus, and glandular trichome density of V. myrtillus and decreased spongy intercellular space of E. hermaphroditum and V. vitis‐idaea. Increased cloudiness decreased leaf dry mass per area of V. myrtillus, palisade thickness of E. hermaphroditum, and stomata density of E. hermaphroditum and V. vitis‐idaea, and increased leaf area and epidermis thickness of V. myrtillus, leaf shape index and nitrogen of E. hermaphroditum, and palisade intercellular space of V. vitis‐idaea. The combined treatment caused thinner leaves and decreased leaf carbon for V. myrtillus, and increased leaf chlorophyll of E. hermaphroditum. We show that under future warmer increased cloudiness conditions in the Subarctic (as simulated in our experiment), vegetation composition and distribution will change, mostly dominated by graminoids and forbs. These changes will depend on the responses of leaf anatomical and biochemical traits and will likely impact carbon gain and primary productivity and abiotic and biotic stress tolerance. [ABSTRACT FROM AUTHOR]