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[Display omitted] • NDVI shows an overall increasing trend from 2000 to 2020. • The Hexi region shows a warming and wetting trend. • Extreme precipitation is more important for NDVI. • The lag effect of NDVI on climate extremes varies by indicators and spaces. Climate extremes significantly affects vegetation dynamics, and understanding the relationship between dryland vegetation and climate extremes is crucial for regional ecological security and disaster warning. According to meteorological and satellite remote sensing data, the paper analyses the dynamics of normalized difference vegetation index (NDVI) and climate extremes in the Hexi region from 2000 to 2020 using Theil-Sen Median, Mann-Kendall and linear regression methods; the relationship between climate extremes and vegetation dynamics is revealed using Pearson correlation and boosted regression trees (BRT) models. On this basis, the time-lag effect of NDVI in response to climate extremes was further investigated. The results show that the NDVI in the Hexi region increased from 2000 to 2020, with significant greening (67.72 %) and a small amount of degradation concentrated in the desert in the northwest and the oasis in the southeast. The correlation between climate extremes indicators and NDVI shows a large spatial heterogeneity, with extreme precipitation showing a high importance for all regions except oasis. NDVI has no lag or 1 month lag for extreme temperature, no lag for max 1-day precipitation amount (Rx1day) for areas other than mountainous areas, and a 3-month lag for max 5-day precipitation amount (Rx5day) for extensive areas. The results of this study could serve as a reference for the study of the relationship between vegetation dynamics and climate extremes in arid and semi-arid regions, and provide a theoretical basis for the establishment of scientific and reasonable strategies for regional vegetation restoration and conservation. [ABSTRACT FROM AUTHOR]

• A proxy based on mass movements for assessing climate change was proposed. • The periodicity of mass movements conforms to the changing patterns of traditional climate proxies. • Climate change determines the spatial and temporal distribution of mass movements. The spatial and temporal distribution, as well as the formation and evolution of mass movements in the Qinghai-Tibet Plateau orogenic belt, have been extensively discussed. We gathered research papers focusing on the ages of Quaternary residual deposits associated with mass movements in the surrounding orogenic belts of the Qinghai-Tibet Plateau. A total of 172 large-scale typical deposits and their ages were analyzed to explore the primary driving mechanisms behind mass movements in the Qinghai-Tibet Plateau. As these deposits were collected from diverse geological environments and the ages primarily concentrated in the Late Pleistocene and Holocene periods, we categorized mass movements with ages younger than 140 ka into three distinct regional climate systems: the Indian Summer Monsoon, the East Asian Summer Monsoon, and the Westerlies. The relationship between the emergence of mass movements and climate change was thoroughly investigated. Our research indicates that mass movements can serve as a reliable proxy for indicating climate change. The cycles of mass movements are closely synchronized with the warm and cold alternations of regional climates, holding significant importance in reshaping the environmental evolutionary history. We propose that the extensive mass movements in the Qinghai-Tibet Plateau are primarily driven by periodic climate variations, although they may not exhibit a perfect one-to-one correspondence. [ABSTRACT FROM AUTHOR]

• The natural variability of directly observed soil thermal conductivity was low. • Soil moisture can explain at least 50 % of soil thermal conductivity variability. • The effect of soil thermal conductivity on active layer thickness was insignificant. • Active layer thickness negatively correlates with soil moisture. The knowledge of soil thermal properties is important for determining how a soil will behave under changing climate conditions, especially in the sensitive environment of permafrost affected soils. This paper represents the first complex study of the interplay between the different parameters affecting soil thermal conductivity of soils in Antarctica. Antarctic Peninsula is currently the most rapidly warming region of the whole Antarctica, with predictions of this warming to continue in the upcoming decades. This study focuses on James Ross Island, where the Abernethy Flats automatic weather station is located in a lowland area with semi-arid climate. Air and ground temperature, soil heat flux and soil moisture during the thawing season were monitored on this site from 2015 to 2023. Moreover, two approaches to determining soil thermal conductivity were compared – laboratory measurements and calculation from field data. During this period, mean annual temperatures have increased dramatically for both air (from −6.9 °C in 2015/2016 to −3.8 °C in 2022/2023) and ground (from −6.5 °C to −3.2 °C), same as active layer thickness (from 68 cm to 95 cm). Average soil thermal conductivity for the thawing period reached values between 0.49 and 0.74 W/m.K−1 based on field data. Statistically significant relationships were found between the seasonal means of volumetric water content and several other parameters – soil thermal conductivity (r = 0.91), thawing degree days (r = −0.87) and active layer thickness (r = −0.88). Although wetter soils generally have a higher conductivity, the increase in temperature exhibits a much stronger control over the active layer thickening, also contributing to the overall drying of the upper part of the soil profile. [ABSTRACT FROM AUTHOR]

• Role of periglacial regions in mercury (Hg) cycling in the Antarctic coastal zone. • Spatial variability of Hg and MeHg concentrations in soil of ice-free areas. • Study confirms link between weathering of rocks and the Hg concentration in soil. • Presence of animals, e.g. penguins and seals, impacts the concentration of Hg in soil. • OM is a key factor affecting Hg distribution across Antarctic terrestrial ecosystems. The Antarctic plays a critical role in global mercury cycling as both a sink of Hg and, in response to rapid global warming, an emerging source of Hg through its release from thawing permafrost and recessing glaciers. At the present time, Antarctica and surrounding areas have little mercury contamination in comparison to other regions of the world. Understanding the sources and transformations of Hg in the Antarctic will be particularly important in predicting the role of a changing environment in the mercury cycle as emissions and global climate change. Study samples were collected at 12 stations, categorized into three groups based on the human or animal presence and flora. Sampling took place in December 2018 and January 2019, and soil and parent rock samples were collected and analyzed for total mercury concentration and its fractions using atomic absorption spectroscopy. Bedrock samples collected on the coast of Admiralty Bay were found to have low organic matter content, while soil samples from the west shore of the bay had a high variability of organic matter content, ranging from 3 % to 41 %. The concentration of total mercury in bedrock ranged from 2.1 ng/g to 15.0 ng/g, and in soil samples, the total mercury concentration ranged from 4.7 ng/g to 143.1 ng/g. This paper reviews current knowledge of Hg cycling in the Antarctic, including its sources, fate, and effects on the ecosystem. The implications of climate change for Hg cycling in the region are also discussed, highlighting the need for continued research to better understand the potential impacts of Hg contamination in the Antarctic. [ABSTRACT FROM AUTHOR]

[Display omitted] • Droughts and floods are increasing worldwide. • Changes in soil moisture affect the soil microbiome. • Climate change affects the soil environment. • Changes in the soil environment affect crop production. • Drought and floods have a negative impact on agriculture. Climate change is progressing and is already visible to the naked eye around the world. Hydrological events associated with climate change, i.e. floods and droughts, have reached extreme levels in recent years. Researchers warn that these phenomena will continue to intensify. According to recent reports, the number of extreme weather events, including hydrological phenomena, has increased by 60% in Europe over the last three decades. Both water shortages and water surpluses affect the soil environment and its functions. This in turn has a direct impact on crops and agriculture. For example, in the US alone, droughts and floods were responsible for more than 70% of the decline in cereal yields in 2011 alone. However, the soil environment is a complex ecosystem that is not yet fully understood, making it difficult to predict the impact of climate change on its quality and functioning. In this paper, we discuss the effects of floods and droughts on the soil microbiome and the implications of these changes for agriculture. We suggest that changes in soil moisture are an important factor affecting crop growth and yield, which is of great importance for global food security. [ABSTRACT FROM AUTHOR]

• Rapid geomorphological evolution occurred in the erodible lithology and semiarid climate of southern Italy. • A deposition phase during the Little Ice Age (LIA) was the last global cold climatic phase. • Badland incision occurred during Mediaeval Warm Period and continued in stably alternating phases until 1700 CE. • Valley aggradation ended early in 1850 as a phase of historic arroyo cutting began. • Geomorphological evolution around Basilicata during the LIA was very rapid and controlled by extreme surface process sensitivity to climate change. There is a general consensus that the increased frequency of extreme climatic events will quickly change the morphology of the landscapes in the Mediterranean area. Knowing and understanding the expected changes becomes crucial for defining future adaptive strategies. This paper deals with the very rapid geomorphological evolution in an emblematic Mediterranean area, the Basilicata region of southern Italy, during the last 300 years. The results show that the landscape evolution was mainly controlled by the extreme sensitivity of surface processes to climate change. Landslides, a new cycle of the formation of badland landforms such as calanchi and biancane, and an aggradation/incision phase in the main river valleys have completely reshaped the landscape of the Bradanic Trough, whereas fresh eroded material was moved to the coast. New data on valley-fill alluvium in the Basento River and one of its main left tributaries, the Vella stream, show ages ranging from 1700 to 1850. This deposition phase coincides with the Little Ice Age, an epoch of global climate variability. Previous literature showed that the alluvium of this age consists of a mappable stratigraphic unit outcropping in all the large alluvial valleys of the Basilicata and Mediterranean regions. Palaeoclimate and high-resolution palaeoflood data indicate that valley-fill alluviation occurred during a long humid period. Valley aggradation ended in approximately 1850 with the beginning of a new phase of historic arroyo cutting, mainly due to high magnitude-low frequency rainy events within prolonged drought periods. The stream incision drew the terminal dissection of the clayey slopes into biancana rounded morphologies. These data seem to be confirmed by the comparable heights of about 3 m, both of the biancane and of the fluvial terraces. [ABSTRACT FROM AUTHOR]

• Land use and land cover classes homogenize within-class differences in vegetation density, type and other characteristics that influence surface erosion. • When these classes are used to estimate current and projected future RUSLE C-factor for native vegetation, this introduces significant error. • Remote sensing methods can be used to assess intra-class variation in C-factor, improving the soil loss estimate. • A strong, predictive relationship exists between remotely-sensed C-factor values and climate. • Current and projected changes in climate can be used to directly estimate C-factor, improving the estimate of current and future soil loss rates. This new method provides a low-cost, efficient and reliable estimate of future C. Understanding how reservoir sedimentation rates may evolve due to climate change is essential for projecting future changes in reservoir water storage capacity. The Revised Universal Soil Loss Equation (RUSLE) is commonly used to assess regional soil loss rates because of its suitability for working with the coarse temporal and spatial scale of climate model outputs. Application of the RUSLE for projecting future erosion rates is constrained by the relatively limited number of classes used in projected changes of native vegetation: this typically reduces a wide range of variation in RUSLE cover (C) factors to a single value per class, and these classes may be insensitive to changes in species composition and canopy density with time and space. This paper develops a low-cost, efficient, and objective approach to projecting future C values directly based on widely available Landsat data, downscaled climate model data, and a limited number of terrain variables. Observed C is estimated from Landsat-derived Normalized Difference Vegetation Index (NDVI) and Modified Soil-Adjusted Vegetation Index (MSAVI) values using standard methods. A linear relationship is established between the observed C values and average annual antecedent temperature, average annual antecedent precipitation, latitude, and percent sand (adjusted R2 = 0.75604, 0.7543, and RMSE = 0.09448, 0.07043, respectively). A proof of principal study demonstrates that, unlike when land cover classes are used to estimates C, a RUSLE model driven by the regression-based C provides a correct order-of-magnitude estimate of observed long-term erosion and sediment yield rates (e.g., an estimate of 2.9–3.2 t ha−1 y-1 is obtained where observed rates range from 1.2 to 3.9 t ha−1 y-1 for the same time period, and up to 8 t ha−1 y-1 historically, while standard formulations of RUSLE yield 16.1 and 0.3 t ha−1 y-1). Using climate model data to estimate both precipitation intensity (R factor) and C in the RUSLE model results in basin wide projected end 21st century soil erosion rates for relative concentration pathway 8.5 of 5.5–7.5 t ha−1 y-1, consistent with expectations for accelerated soil loss in the study area as climate change reduces soil moisture while increasing precipitation intensity. The same model driven by land cover class estimates of C produces soil loss rates an order of magnitude smaller (0.3–0.4 t ha−1 y-1), consistent with a much more heavily vegetated landscape than could be supported under the increasingly arid projected climate. [ABSTRACT FROM AUTHOR]

• Warming effects increased with warming duration and magnitudes. • Warming effects on C and N concentrations remain globally invariant. • [C] and [N] responded inconsistently to warming between above- and belowground. • Warming effects on [C] and [N] are linked to soil moisture and soil pH. Global warming has significantly affected the terrestrial C and N cycling processes. Whereas, it is unclear how global warming impacts the C and N concentrations in the above- and belowground ecosystems. We performed a meta-analysis with the results presented in 136 papers and 1886 observations. The data reveals that global warming increased C concentrations in leaf, shoot, and microbial biomass and N concentrations in the shoot. The C:N ratios of microbial biomass also increased under conditions of warming. However, the soil C concentration and soil C:N ratios decreased. Furthermore, these responses are more evident with longer warming duration and elevated warming magnitudes. The warming effects on C and N concentrations and C:N ratios never changed with warming methods, ecosystem types, or background climates. Also, in response to warming, soil moisture was negatively correlated with leaf C concentration as well as C:N ratio in microbial biomass. Soil pH response to warming was in a negative correlation with those of soil C concentration, soil C:N ratio, and microbial biomass C concentration. Our analysis has identified some key ecosystem processes that can be potentially implemented into the ecosystem models for predicting how warming affects future terrestrial C and N dynamics. [ABSTRACT FROM AUTHOR]

• Fire-induced hydrological impacts were assessed using the OpenLISEM model. • Rainfall dominated the catchment hydro-sedimentary responses before and after fire. • Fire led to a mean increase of 57% in peak discharge and up to 31% in sediment yield. • Sediment sources partly changed from croplands to burnt areas. Wildfires can have strong negative effects on soil and water resources, especially in headwater areas. The spatially explicit OpenLISEM model was applied to a burned catchment in southern Portugal to quantify the individual and combined impacts of wildfire and rainfall on hydrological and erosion processes. The companion paper has calibrated and assessed model performance in this area before and after a fire. In this study, the model was applied with design storms of six different return periods (0.2, 0.5, 1, 2, 5, and 10 years) to simulate and evaluate pre- and post-wildfire hydrological and erosion responses at the catchment scale. Our results show that rainfall amount and intensity played a more important role than fire occurrence in the catchment discharge and sediment yields. Fire occurrence was found to be an important factor for peak discharge, indicating that high post-fire hydro-sedimentary responses are frequently related to extreme rainfall events. The results also suggest a partial shift from runoff to splash erosion after fire, especially for higher return periods. This can be explained by increased splash erosion in burned upstream areas saturating the sediment transport capacity of surface runoff, limiting runoff erosion in downstream areas. Therefore, the pre-fire erosion risk in the croplands of this catchment was partly shifted to a post-fire erosion risk in upper slope forest and natural areas, especially for storms with lower return periods, although erosion risks in croplands were important both before and after fires. These findings have significant implications to identify areas for post-wildfire stabilization and rehabilitation, which is particularly important given the predicted increase in the occurrence of fires and extreme rainfall events with climate change. [ABSTRACT FROM AUTHOR]

• Identify ancient flood events, which may be the reason for decline of the culture. • Pollen and heavy metals can be used to reflect the strength of human activities. • Pollen and heavy metals revealed the process of culture from prosperity to decline. • This paper defined the chronology from prosperity to decline of Shijiahe culture. • Climate change has been revealed by pollen and heavy metals since 4800 cal. yr BP. The Shijiahe Culture (ca. 4800–4100 yr BP), which originated in the middle Yangtze Basin, was a milestone of prehistoric Chinese civilization. To reveal the interactions between climatic changes and human activities during this time interval, the geochronology and multiple proxies (pollen and heavy metals) of samples from a 220-cm-deep outer wall at the Sanfangwan Site (a typical site of the Shijiahe Culture) were analyzed. Radiocarbon dating indicates that the age range of the Sanfangwan Site is ca. 4800 to 4100 cal. yr BP. From ca. 4800 to 4600 cal. yr BP (the early Shijiahe Culture), pollen assemblages were dominated by Gramineae and an anthropogenic plant community (e.g. Ranunculaceae, Chenopodiaceae, Labiatae, and Cruciferae), indicating an expansion in rice agriculture during this interval. High metal concentrations in the same interval indicate a large flux of metals from smelting and farming activities. Between ca. 4600 and 4100 cal. yr BP (the middle and late Shijiahe Culture), decreases in Gramineae and anthropogenic pollen mirrored the recession of farming. Concurrent decreases in heavy metals may be attributable to a decline in the smelting industry. Three episodes of high pollen concentrations and visible increases in hygrophyte pollen, Pinus pollen, and fern spores at 4600–4550, 4450–4350, and 4200–4100 cal. yr BP probably indicate the occurrence of several flooding events during the middle and late Shijiahe Culture, resulting in the migration of local inhabitants. This study highlights the driving effect of flood events on the collapse of the Shijiahe Culture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Future impacts of LULC and climate on the streamflow and erosion by new approaches. • SWAT model was applied to estimate future runoff-erosion. • Future climate data generated using GCM coupled to regional circulation model. • The methodology contextualizes potentially significant hydrological changes. • The changes may impact the sustainability of water resources management. Water management in the Caatinga/Atlantic forest ecotone in Brazil is critically dependent on better understanding of potential future changes in streamflow and sediment dynamics. This paper evaluates both the future impacts of land use and land cover (LULC) changes and the impacts of climate change on the streamflow and sediment yield in the Tapacurá River basin in northeastern Brazil, using a novel combination of approaches. Projected climate data derived using global circulation model HadGEM2-ES were coupled to regional circulation model ETA-CPTEC/HadCM3 for two representative concentration pathways (RCP 4.5 and 8.5), with bias correction. Two future LULC scenarios were generated: (a) optimistic (current LULC), and (b) pessimistic (land use change trends continue), using the multilayer perceptron algorithm (MP). The Soil and Water Assessment Tool (SWAT) model was used to estimate future streamflow and erosion for different periods (2011–2040, 2041–2070 and 2071–2099). The SWAT model was calibrated for period of 1995–2003 and validated for 2004–2013. The results showed good accuracy in relation to R2, NSE and PBIAS for the calibration and validation of the runoff, as well as for the verification of the sediment yield. Simulations indicated significant increases in erosion for the pessimistic scenario under RCP 8.5, followed by the pessimistic scenario and RCP 4.5. Lower sediment yields occurred for the optimistic and RCP 8.5, with lower still for the optimistic and RCP 4.5. However, the latter estimates are still considerably higher than baseline conditions. Although higher flows are found for some scenarios, the increases in sediment yield have serious implications for reservoir siltation and storage reduction. Despite modeling uncertainty, the results demonstrate that the proposed methodology has promising scope to contextualize potentially significant regional hydrological changes which have implications for land and biodiversity management and the sustainability of water resources in the Caatinga/Atlantic forest ecotone. [ABSTRACT FROM AUTHOR]