Changes In Vegetation Cover Research Articles

Impacts of Hurricane Michael on Watershed Hydrology: A Case Study in the Southeastern United States

Hurricanes are one of the most significant threats to coastal plain forest ecosystems and urban communities of the southeastern U.S., but their implications for watershed hydrology are unclear. Hurricanes have the potential to alter water balances, causing extensive flooding, biogeochemical cycle disruption, and water quality degradation, saltwater intrusion, and increased nutrient sedimentation export in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf coast, the Florida panhandle, southwestern Georgia, and southeastern Alabama. Through empirical (Double Mass Curve) and process-based ecohydrological modeling (WaSSI model) on long-term streamflow data, we explored whether vegetation damage caused by this hurricane resulted in an increase in streamflow two years after the extreme event. We found that monthly streamflow from the Chipola River watershed with an area of 2023 km2 did not change (<6%) appreciably during the first two years following the storm, arguably because only a fraction of the gauged watershed lost substantial tree cover. However, spatially explicit hydrological modeling suggested that several sub-watersheds with the highest decreases in the Normalized Difference Vegetation Index (NDVI) significantly increased their monthly streamflow in 2019 by up to 22%. These modeled streamflow anomalies subsided by the second growing season when vegetation recovered. Overall, this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts on the hydrology of this watershed, and the hydrology of coastal watersheds may be more resilient to hurricane disturbances than previously thought.

The importance of continental evaporation for precipitation in Colombia: A baseline combining observations from stable isotopes and modelling moisture trajectories

AbstractThe hydroclimatology of Northern South America responds to the coupling between the Pacific and Atlantic oceans, the Amazon–Andes interactions, and the orographic barrier of the regional Andes. The relative contributions of oceanic and terrestrial moisture sources have been mostly evaluated in modelling studies, with limited observational data for validation. We combine observations from stable isotopes in precipitation and output from the Lagrangian moisture trajectory tracking model FLEXPART to characterize and contrast the relative contribution of oceanic (from the Atlantic and the Pacific) and terrestrial (from different regions in the continent) moisture sources to mean monthly precipitation in the Andes and Caribbean regions of Colombia. Our results indicate that most moisture becoming rain in the region has an atmospheric residence time that deviates from commonly assumed 10 days. These residence times vary between source and sink regions from 1 day in the case of recycling to more than 10 days in Andean precipitation originating in the Atlantic Ocean. Common integration times for both regions from all sources are commonly in the order of three to 7 days. Most precipitation in the region comes from terrestrial sources including moisture recycling from the same region (>30% for all months), the Orinoco River basin (up to 28% in April), and the northern Amazon basin (up to 17% in June, July, and August); followed by individually considered oceanic sources including the Tropical South Pacific (up to 30% monthly in October, November and December) and Tropical North Atlantic (up to 30% monthly for January). The fact that a significant proportion of rainfall is recycled highlights that water availability in the Andean and Caribbean regions of Colombia could potentially be altered by current widespread and pervasive changes in vegetation cover. More generally, our results highlight the need to assess the hydrological consequences of land cover change in South America, particularly in a country like Colombia where water, food, and energy security all depend directly on precipitation.

Desertification in the Mu Us Sandy Land in China: Response to climate change and human activity from 2000 to 2020

China is a country largely affected by desertification. The main purpose of this article is to analyze interannual and seasonal changes in fractional vegetation cover (FVC) in the Mu Us Sandy Land (MUSL). It uses fused remote sensing data to quantitatively analyze the response of FVC to climate change and human activities. The results showed that desertification in the MUSL had improved over the past 20 years. Grade V desertification decreased from more than 60% in 2000 to about 15% in 2020. In some years, degradation appeared to be affected by climate factors and human activity, especially in the northwestern portion of the study area. The FVC in summer was slightly higher than that in autumn and far higher than recorded in spring and winter. Spatially, the northwestern and central parts of the study area were unstable, with high coefficients of variation. FVC gradually increased from northwest to southeast, and areas with the fastest increase in FVC were concentrated along the eastern and southern edges of the study area. The correlations between FVC and precipitation and dryness were slightly positive, but the correlation between FVC and temperature showed regional differences. The increase of population density is not a key factor limiting the growth of vegetation; the policy of “grazing prohibition, grazing rest, and rotational grazing” has allowed the restoration of vegetation; and afforestation is an effective way to promote the increase in FVC.

Centennial-Scale Land-Cover Change on Babeldaob Island, Palau

We used publicly available land-cover datasets (1921, 1947, 1976, 1992, 2001, 2006, 2014) to assess land-cover change on Babeldaob Island, Republic of Palau. Land-cover data were organized, classified, and summarized by area and percentage of island cover for forest, mangrove, non-forest vegetation, and non-vegetation. Japanese colonial administration of the island between 1921 and 1947 included industrial mining and agriculture, which reduced total non-mangrove forest cover by 16%. Temporal vegetation cover dynamics from 1947 through 2014 indicate unassisted forest regeneration of 12% with a concomitant decrease in non-forest vegetation including abandoned agriculture, the majority of which happened by 1976. Mangrove cover appears to have remained stable throughout the 93 year study period. Ground-truth observations showed the highest rates of vegetation cover change since 1976 for non-vegetated areas, followed by marsh and swamp forest. The proportion of non-vegetated cover increased at least twofold after WWII, with at least half comprising roads. Contrary to other tropical geographies, we saw forest expansion following completion of a major perimeter road. However, the larger landscape is permeated by dynamic forest edges subject to wildfire and other land-use disturbances.

Vegetation Cover Analysis Based on NDVI in Moushuni Island, Sundarban, India

Abstract: Moushuni island is one of the island of Indian Sundarban, but changes of vegetation cover is occurred due to natural and anthropogenic activity. The aim of this paper is to emphasis the changes of vegetation cover between 2000 and 2020 of Moushuni island. Vegetation indices like Normalised Difference Vegetation Index (NDVI) is used to identify the changes of vegetation cover from 2000 to 2020. Based on NDVI value, the study area is classified into four classes -Dense vegetation, Sparse Vegetation(vegetated), No vegetation and Water. Result shows an overall increase of dense vegetation cover (8.1%) in the island. The percent of vegetated area coverage is decreased during the study period. The major cause of decrease vegetation may be attributed to increase of rural settlement and salinisation. Keywords: Moushuni, NDVI, Dense vegetation, Vegetated, Salinisation.

Investigation of changes in vegetation cover associated with changes in its hydro-climatic drivers in recent decades over North Sub-Saharan Africa

Investigation of changes in vegetation cover associated with changes in its hydro-climatic drivers in recent decades over North Sub-Saharan Africa

Assessment of spatiotemporal dynamics of land and vegetation cover change detection in Maze National Park, Southwest Ethiopia.

Biodiversity conservation areas include National Parks which are integral parts of protected areas. In parks, the dynamics of land and vegetation covers are significantly affected by anthropogenic activities and natural factors. These resources are exposed to challenges due to unwise practices. Assessing and monitoring the status of park's natural resources enables us to understand the extent of land and vegetation resources. Few studies have been conducted in Maze National Park (MzNP) but none of them quantified the land and vegetation cover dynamics. The purpose of this study is, therefore, to quantify the extents spatiotemporal dynamics of land and vegetation cover of MzNP using GIS and RS technology considering three decades Landsat images acquired from USGS. GPS and GCPs were collected for the analysis of land cover classification and accuracy assessment, respectively. The trend analysis result revealed that scattered tree and grass land cover area have increased from 19.8% in 1987 to 51.6% in 2019. The area of sparse vegetation cover increased from 19.7% in 2000 to 78.4% in 2019. Highly dense and dense vegetation cover decreased remarkably. Accuracy assessment was 98% and computed Kappa coefficient was 0.97. The results suggested that the extent of MzNP's vegetation cover change was basically due to anthropogenic pressure. This study could be used to alarm responsible bodies to restructure and implement better environmental protection strategies for restoration of the rapidly deteriorating vegetation resource of MzNP.

Assessing the Impact of Wildlife on Vegetation Cover Change, Northeast Namibia, Based on MODIS Satellite Imagery (2002-2021).

Human–wildlife conflict in the Zambezi region of northeast Namibia is well documented, but the impact of wildlife (e.g., elephants) on vegetation cover change has not been adequately addressed. Here, we assessed human–wildlife interaction and impact on vegetation cover change. We analyzed the 250 m MODIS and ERA5 0.25° × 0.25° drone and GPS-collar datasets. We used Time Series Segmented Residual Trends (TSS-RESTREND), Mann–Kendall Test Statistics, Sen’s Slope, ensemble, Kernel Density Estimation (KDE), and Pearson correlation methods. Our results revealed (i) widespread vegetation browning along elephant migration routes and within National Parks, (ii) Pearson correlation (p-value = 5.5 × 10−8) showed that vegetation browning areas do not sustain high population densities of elephants. Currently, the Zambezi has about 12,008 elephants while these numbers were 1468, 7950, and 5242 in 1989, 1994, and 2005, respectively, (iii) settlements and artificial barriers have a negative impact on wildlife movement, driving vegetation browning, and (iv) vegetation greening was found mostly within communal areas where intensive farming and cattle grazing is a common practice. The findings of this study will serve as a reference for policy and decision makers. Future studies should consider integrating higher resolution multi-platform datasets for detailed micro analysis and mapping of vegetation cover change.

Unfolding the Success of Positive Human Interventions in Combating Land Degradation

A global challenge to sustainable development is land degradation, and to achieve land degradation neutrality, monitoring, mapping, and impact assessment of ongoing ecological restoration efforts is necessary. Here, we analyze the desertification process and role of restoration projects at a spatial and temporal scale in Mu Us Desert from 2001 to 2018. We used 17 years of data to (1) assess the vegetation trend including its significance and map land degradation based on Sustainable Development Goal Indicator 15.3.1 (2) address how vegetation activity has changed under the influence of restoration programs and climate change (3) estimate how successful are the positive human interventions to achieve Land degradation neutrality. Results showed an overall increasing vegetation trend (85.69% significant increasing) and a partial decreasing vegetation trend (1.33% significant decreasing) in Mu Us desert. Ecological restoration activities are found to be one of the key driving forces of vegetation restoration in the desert, however, limited impact of climatic factors on vegetation cover change was observed. Results revealed that 41.42% of total significant restoration is attributed to ecological restoration programs out of which 40.42% area has shown improvement in all three sub-indicators of land degradation.

Identifying the Impacts of Climate Change and Human Activities on Vegetation Cover Changes: A Case Study of the Yangtze River Basin, China.

The normalized difference vegetation index (NDVI) is a useful indicator to characterize vegetation development and land use which can effectively monitor changes in ecological environments. As an important area for ecological balance and safety in China, understanding the dynamic changes in land cover and vegetation of the Yangtze River Basin would be crucial in developing effective policies and strategies to protect its natural environment while promoting sustainable growth. Based on MODIS-NDVI data and meteorological data from 2000 to 2019, the temporal and spatial distribution of vegetation coverage in the Yangtze River Basin during the past 20 years were characterized, and the impacts of human activities and climate change were quantitatively evaluated. We drew the following research conclusions: (1) From 2000 to 2019, the vegetation cover of the Yangtze River Basin presented a fluctuating inter-annual growth trend. Except for the Taihu Lake sub-basin, the vegetation cover in other sub-basins showed an upward trend. (2) The vegetation cover exhibited a spatial distribution pattern of “high in the middle and low in the east and west”, with the multi-year average value of NDVI being 0.5153. (3) Areas with improved vegetation cover were significantly larger than the areas with degraded foliage. The central region has stronger overall trend of change than the east, and the east is stronger than the west. These vegetation cover changes are largely related to anthropogenic activities. (4) Vegetation cover changes due to precipitation and temperature exhibited significant spatial heterogeneity. While both temperature and precipitation influenced vegetation cover, the temperature was the leading climate factor in the area. (5) Anthropogenic and climate factors jointly promoted the change of vegetation cover in the Yangtze River Basin. Human activities contributed 79.29%, while climate change contributed 20.71%. This study could be used in subsequent studies analyzing the influencing factors affecting long-term vegetation cover in large-scale watersheds.

An Analysis of the Effects of Anthropogenic Factors on Vegetation Cover Change in Guanzhong, China

Exploring the impacts of anthropogenic factors on vegetation cover and future spatiotemporal trends in vegetation cover change are of great practical significance for sustainable management of the ecological environment. This study used the residual, trend analysis, Hurst index, and geographic detector methods to explore the spatiotemporal trends in the effects of anthropogenic factors on vegetation cover in Guanzhong, China from 2001 to 2018. The contributions of different kinds of anthropogenic factors to vegetation cover were quantitatively decomposed to identify those with the most effect. The main conclusions of the study included: 1) Although there was a positive trend in the effects of anthropogenic factors on vegetation cover from 2001 to 2018, this trend was projected to become negative in the future. This transition was evident in 45.53% of the total study area, mainly distributed in the cities of Baoji, Weinan, and Xianyang. The effects of artificial factors on reversing this deteriorating trend in the region should be noted. 2) The factors with the greatest influences on vegetation cover changes were popular tourist attractions, transportation, and urbanization rates. The influences of various factors on vegetation cover showed temporal variation, driven by societal and economic development, indicating the complexity and diversity of the influences of anthropogenic factors on vegetation cover. 3) Sustainable development should be promoted and the pressure on the ecology resulting from popular tourist attractions, the transportation network, and rapid urbanization should be reduced.

Dual Influence of Climate Change and Anthropogenic Activities on the Spatiotemporal Vegetation Dynamics Over the Qinghai‐Tibetan Plateau From 1981 to 2015

AbstractClimate change and human activities have already caused degradation in a large fraction of vegetation on the Qinghai‐Tibetan Plateau (QTP). Many studies report that climate variability instead of overgrazing has been the primary cause for large‐scale vegetation cover changes on the QTP, for example, Lehnert et al., 2016, https://doi.org/10.1038/srep24367. However, it remains unclear how human activities (mainly livestock grazing) regulate vegetation dynamics under climate change. This paper takes the AVHRR/GIMMS Normalized Difference Vegetation Index (NDVI) as an indicator to analyze the growth status of vegetation zones in the QTP, which has highly sensitive to climate change. The spatiotemporal dynamics of vegetation growth between 1981 and 2015 were analyzed. The dual effects of climate change and human activities were examined by correlation analyses of data from 87 meteorological stations and economic statistical data of the QTP. Results show that: (a) The vegetation in central and southwestern QTP with high altitudes was improving due to the warm‐humid climate trend. An increase in temperature and a reduction in the harsh frigid climate at high altitudes due to global warming has resulted in expansions of the vegetated areas, with the NDVI showing a concordant increase. (b) The degraded areas were mainly confined to the northern and eastern QTP, which have high human and livestock population densities. In comparison to gently changing climate regimes, anthropogenic activities such as chronic concentration of population and livestock in the valleys with a less harsh climate exerts a much stronger pressure on vegetation. The study indicates that the anthropogenic pressures are much more intensive than the impact of climate change and are critical for the conservation and sustainable management of the QTP vegetation.

Quantitative analysis of vegetation restoration and potential driving factors in a typical subalpine region of the Eastern Tibet Plateau.

Vegetation restoration is an essential approach to re-establish the ecological balance in subalpine areas. Changes in vegetation cover represent, to some extent, vegetation growth trends and are the consequence of a complex of different natural factors and human activities. Microtopography influences vegetation growth by affecting the amount of heat and moisture reaching the ground, a role that is more pronounced in subalpine areas. However, little research is concerned with the characteristics and dynamics of vegetation restoration in different microtopography types. The respective importance of the factors driving vegetation changes in subalpine areas is also not clear yet. We used linear regression and the Hurst exponent to analyze the trends in vegetation restoration and sustainability in different microtopography types since 2000, based on Fractional Vegetation Cover (FVC) and identified potential driving factors of vegetation change and their importance by using Geographical Detector. The results show that: (1) The FVC in the region under study has shown an up-trend since 2000, and the rate of increase is 0.26/year (P = 0.028). It would be going from improvement to degradation, continuous decrease or continuous significant decrease in 47.48% of the region, in the future. (2) The mean FVC is in the following order: lower slope (cool), lower slope, lower slope (warm), valley, upper slope (warm), upper slope, valley (narrow), upper slope (cool), cliff, mountain/divide, peak/ridge (warm), peak/ridge, peak/ridge (cool). The lower slope is the microtopographic type with the best vegetation cover, and ridge peak is the most difficult to be afforested. (3) The main factors affecting vegetation restoration in subalpine areas are aspect, microtopographic type, and soil taxonomy great groups. The interaction between multiple factors has a much stronger effect on vegetation cover than single factors, with the effect of temperatures and aspects having the most significant impact on the vegetation cover changes. Natural factors have a greater impact on vegetation restoration than human factors in the study area. The results of this research can contribute a better understanding of the influence of different drivers on the change of vegetation cover, and provide appropriate references and recommendations for vegetation restoration and sustainable development in typical logging areas in subalpine areas.

Heterogeneous Impact of Land-Use on Climate Change: Study From a Spatial Perspective

Studies have shown that land and climate interact in complex ways through multiple biophysical and biogeochemical feedbacks. In this interaction mechanism, the carbon fixation effect among different land-use types and objective conditions among different regions have significant gaps, leading to the heterogeneous impact of land-use on climate change. This study takes temperature change as the observation index to reflect climate change, and analyzes the process of land use type adjustment affecting vegetation cover and climate change. Based on the data of 214 countries from 1990 to 2018, this paper uses the spatial Durbin model with temperature lag to verify the heterogeneous impact of land-use on climate change in two dimensions of land-use type (Agriculture, forestry and their subdivision structure) and region (latitude and land-sea difference). The following conclusions are drawn: 1) The impact of different land-use types on climate change is heterogeneous. The impact of agricultural land on climate change is not significant, but the increase of the forest land proportion will help to restrain the rise of national temperature. 2) The impact of land-use on climate change has regional heterogeneity. There is heterogeneity in the impact on climate change among sample countries of different latitudes. The geographical differences make the mechanism of land-use affecting climate change between island countries and mainland countries also have heterogeneity, mainly in that island countries are not affected by the land-use structure adjustment of neighboring countries. 3) A country’s climate change is affected by both its own land-use structure and the land-use structure of neighboring countries, and the latter is more critical. The conclusions in this study provide helpful supplementary evidence for the importance of international climate cooperation and provide a reference for proposing international initiatives to address climate change or establishing an international convention to address climate change.

Modelling Response of Norway Spruce Forest Vegetation to Projected Climate and Environmental Changes in Central Balkans Using Different Sets of Species

The structure and function of many forest ecosystems will be modified as a result of air pollution and climate change. Norway spruce (Picea abies L.) forests are among the first terrestrial ecosystems to respond to this change. We analysed how changes in climate and environmental factors will affect vegetation cover in Norway spruce forests and whether it is possible to assemble a list of diagnostically important/sensitive species that would be the first to react to changes in habitats of Norway spruce in Central Balkan. Significant changes in the vegetation cover of Norway spruce forests are mainly influenced by temperature increases (≈4 °C), and precipitation decreases (≈102 mm) by the end of the 21st century. Projections show that vegetation cover changes and future habitat conditions for Norway spruce forests on podzolic brown soils with a low base saturation and soil pH decreases, and temperature growth and precipitation decline, with the worst in the Rodope montane forest ecoregion. In Dinaric Mountain and Balkan mixed forest ecoregions, the range of natural occurrence of Norway spruce forest will shift to higher altitudes, or to the north. One of the cognitions of this paper is that, through available environmental models and their indices, species from the IUCN Red List should be recognised more properly and included in model calculations.

Modelling regional ecological security pattern and restoration priorities after long-term intensive open-pit coal mining

Long-term intensive open-pit mining can have huge impacts on ecosystems and the services they provide, affecting the integrity of ecosystem structures, functions and process and thus the “ecological security” of a whole mining region. The indirect and direct impacts of mining are spatially and temporally complex and therefore ecological security patterns need to be considered. However, to date there has been little research focusing on ecological security patterns in mining regions. This study aims to model and map ecological security and restoration priorities in an intensive open-cut coal mining region accounting for spatio-temporal changes of multiple ecosystem services. Four ecosystem services including habitat quality, carbon sequestration, water yield, and sediment retention were assessed and mapped in 1990, 2000, 2010, and 2020. Next ecological security patterns and restoration priorities were modelled and characterized using the Self-Organizing Feature Map to identify ecological sources, and circuit theory in Linkage Mapper to characterize connectivity and flows. The results showed that habitat quality, carbon sequestration, and water yield services were most affected by vegetation cover changes due to mining exploitation, while sediment retention was influenced by multiple natural factors, especially topography. Ecological sources, corridors, pinch-points and barriers showed various changing trends due to mined and built-up land expansion over time. Ecological source area declined from 1355.08km2 in 2000 to 584.92 km2 in 2020, while the number of corridors increased from 17 in 2000 to 25 in 2010 and then decreased to 21 in 2020. Although restoration has been conducted on some mine sites, regional-scale restoration needs greater consideration. This study provides decision-makers and stakeholders with a method for assessing regional-scale ecological security and restoration in a holistic and systematic way moving beyond a single mine, which is critical for balancing ecological security protection with minerals production in intensive mining regions.

Winter storm Uri and temporary drought relief in the western climate divisions of Texas

Texas ranks first in the United States in the variety and frequency of most natural disasters, such as flooding, wildfires, hurricanes, winter storms, and droughts. In February 2021, the winter storm named Uri caused an abnormal decline in the air temperature in the southcentral United States, notably in Texas. Right before Uri, most of Texas was going through a drought spell. Thus, this study analyzed how Uri influenced the drought severity, soil profile moisture content, and vegetation cover (Normalized Difference Vegetation Index, NDVI) across Texas. Data used in this analysis was obtained from the web-based geospatial applications gridMET and Crop-CASMA. The collected datasets include the Palmer Drought Severity Index (PDSI), Snow Water Equivalent (SWE), soil moisture, and NDVI at different spatial resolutions. These datasets were aggregated to the county scale using the zonal statistics analysis. The strength of the correlation between SWE and soil moisture was quantified based on the Pearson correlation coefficient. The percentage change in live vegetation cover due to the impact of the frigid temperature and snow coverage across the state was quantified by analyzing the average weekly NDVI before and after the winter storm. There was a reasonably strong correlation between the SWE contribution of Uri and the increase of the rootzone soil moisture (Pearson's r = 0.42). Similarly, the SWE showed a higher correlation with daily rootzone soil moisture with a Pearson's correlation coefficient of 0.49 on March 1. Furthermore, our results revealed a reduction in the NDVI values to less than 0.60 across Texas during the third week of February. Overall, Texas NDVI values seriously decreased due to Uri. Despite its disruptive effects on the state infrastructures and the economy, Uri snow lessened the drought conditions relatively for a short time.

Geospatial solutions for evaluating the impact of the Tigray conflict on farming

Military conflicts strongly affect agricultural activities. This has strong implications for people’s livelihoods when agriculture is the backbone of the economy. We assessed the effect of the Tigray conflict on farming activities using freely available remote sensing data. For detecting greenness, a normalized difference vegetation Index (NDVI) was analyzed in Google Earth Engine (GEE) using Sentinel 2 satellite images acquired in the pre-war (2020) and during war (2021) spring seasons. CHIRPS data were analyzed in GEE to understand the rainfall conditions. The NDVI of 2020 showed that farmlands were poorly covered with vegetation. However, in 2021, vegetation cover existed in the same season. The NDVI changes stretched from − 0.72 to 0.83. The changes in greenness were categorized as increase (2167 km2), some increase (18,386 km2), no change (1.6 km2), some decrease (8269 km2), and decrease (362 km2). Overall, 72% of the farmlands have seen increases in green vegetation before crops started to grow in 2021. Scattered patches with decreases in vegetation cover correspond to irrigation farms and spring-cropping rain-fed farms uncultivated in 2021. There was no clear pattern of changes in vegetation cover as a function of agro-climatic conditions. The precipitation analysis shows less rainfall in 2021 as compared to 2020, indicating that precipitation has not been an important factor. The conflict is most responsible for fallowing farmlands covered with weeds in the spring season of 2021. The use of freely accessible remote sensing data helps recognizing absence of ploughing in crisis times.

Neanderthals in changing environments from MIS 5 to early MIS 4 in northern Central Europe – Integrating archaeological, (chrono)stratigraphic and paleoenvironmental evidence at the site of Lichtenberg

The resilience of Neanderthals towards changing climatic and environmental conditions, and especially towards severely cold climates in northern regions of central Europe, is still under debate. One way to address this is to investigate multi-layered occupation in different climatic intervals, using independently-compiled paleoenvironmental and chronological data. Unfortunately, most open-air sites on the northern European Plain lack a robust chronostratigraphy beyond the radiocarbon dating range, thereby often hampering direct links between human occupation and climate. Here we present the results of integrative research at the Middle Paleolithic open-air site of Lichtenberg, Northern Germany, comprising archaeology, luminescence dating, sedimentology, micromorphology, as well as pollen and phytolith analyses. Our findings clearly show Neanderthal presence in temperate, forested environments during the Mid-Eemian Interglacial, MIS 5e and the latest Brörup Interstadial, MIS 5c/GI 22 (Lichtenberg II). For the previously known occupation Lichtenberg I, we revise the chronology from the former early MIS 3 (57 ± 6 ka) to early MIS 4/GS 19 (71.3 ± 7.3 ka), with dominant cold steppe/tundra vegetation. The early MIS 4 occupation suggests that Neanderthals could adjust well to severely cold environments and implies recurring population in the region between MIS 5 and MIS 3. The artefact assemblages differ between the temperate and cold environment occupations regarding size, blank production, typology and tool use. We argue that this distinctness can partially be explained by different site functions and occupation duration, as well as the availability of large and high-quality flint raw material. Raw material availability is in turn governed by changing vegetation cover that hindered or fostered sediment redeposition as a provider of flint from the primary source of the glacial sediments nearby.

Analysis of spatial and temporal changes of vegetation cover and its driving forces in the Huainan mining area.

The Huainan mining area is rich in coal resources and has sparse vegetation and many collapsed waterways. Large-scale and long-term underground coal mining has led to a fragile ecological environment in the mining area, and it is urgent to solve the contradiction between coal development and ecological environmental protection. The Huainan mining area was selected as the research object, and the vegetation cover was extracted using 10-phase Landsat multispectral remote sensing images from 1989 to 2021 to analyze its spatial and temporal changes and driving forces to provide a scientific basis for the guided restoration of the ecological environment in the region. Combined with the image dichotomous model, regression slope, correlation coefficient, and standard deviation of vegetation cover grid points in different time series, standard deviation ellipse, and center of gravity migration, we analyzed the spatial and temporal variation pattern of vegetation cover for 33 years and revealed the responses of temperature, precipitation, population density, GDP, and afforestation area to vegetation cover. Results show the following: (1) from 1989 to 2021, the overall vegetation cover in the study area tended to decrease with 36.48% of the areas increasing and 63.52% of the areas decreasing, primarily in the very low and medium range; (2) the center of gravity of different types of vegetation cover generally shifted from north to south during 33 years; (3) climate and social activities had a substantial effect on the spatial heterogeneity of the vegetation cover in the study area. There is significant spatial heterogeneity in the effects of climate and social activities on the vegetation in the study area with human activities negatively correlating with vegetation cover. Mining activities are the primary driver of the evolution of regional vegetation cover, with climate change serving as a secondary driver.