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A good understanding of the processes of land surface temperature (LST) change is important for assessing regional climate change. In the present study, we obtained the MODIS MOD11A2 LST products over the Yangtze River Delta (YRD) from 2001 to 2020. In order to comprehensively assess the spatial and temporal variability of LST in the YRD region over the past two decades, the Theil–Sen Median trend analysis and Mann–Kendall test, BFAST01 trend decomposition, and landscape pattern analysis were used in this study. We show that the rate of linear change in LST in the YRD ranges from −0.019 °C/month to 0.046 °C/month. The BFAST01 trend decomposition identifies more details of LST change and monotonic increases, reversal increase, and interruption increase are the main warming trends. The distribution of the different trend types shows strong aggregation with high spatial heterogeneity. The LST breakpoints are mainly located in the northern and southern YRD, which frequently occurred during 2010–2013. Of the various land types, breakpoints occur most frequently in cropland and high NDVI (0.5–0.7) areas, and the intensity of most of them is within 2 °C. In addition, much stronger warming occurs in urban areas than in other land types. Our study provides a better understanding of the dynamics of LST in the YRD region over the past 20 years and highlights that breakpoints cannot be circumvented in regional temperature assessment. [ABSTRACT FROM AUTHOR]

Simple Summary: The Asian longhorned beetle, Anoplophora glabripennis, is a worldwide invasive creature that has invaded the world for more than 20 years. Although previous studies have predicted the distribution range of A. glabripennis, this single species distribution prediction cannot provide more potential management strategies for the control of invasive organisms. In this study, we incorporated two important natural enemies (D. helophoroides and D. major) of A. glabripennis into the prediction model. We found that climate change led to the northward migration of the suitable areas of A. glabripennis and its natural enemies. In China, only the occurrence regions of A. glabripennis are mainly distributed in parts of Xinjiang, Xizang, and Qinghai. In other occurrence regions of A. glabripennis, control models of A. glabripennis + D. helophoroides, A. glabripennis + D. major, or A. glabripennis + D. helophoroides + D. major were found. Fortunately, part of the areas in Xinjiang, Xizang, and Qinghai are potentially suitable for D. helophoroides and D. major under future climatic conditions. Therefore, these two natural enemies may be used in these regions to control A. glabripennis in the future. The Asian longhorned beetle, Anoplophora glabripennis, is a forestry pest found worldwide. A. glabripennis causes serious harm because of the lack of natural enemies in the invaded areas. Dastarcus helophoroides and Dendrocopos major are important natural enemies of A. glabripennis. MaxEnt was used to simulate the distribution of D. helophoroides and D. major in China, and their suitable areas were superimposed to pinpoint which regions are potentially appropriate to release or establish natural enemy populations under current and future conditions. The results showed that, with climate change, the suitable areas of D. helophoroides and D. major migrated northward; the centroid shift of A. glabripennis was greater than those of D. helophoroides and D. major. From current conditions to 2090, the suitable area of A. glabripennis, D. helophoroides, and D. major will increase by 1.44 × 104, 20.10 × 104, and 31.64 × 104 km2, respectively. Northern China (e.g., Xinjiang, Gansu, and Inner Mongolia), where A. glabripennis causes more serious damage, is also a potentially suitable area for D. helophoroides and D. major, and this provides a potential strategy for the management of A. glabripennis. Therefore, we suggest that natural enemies should be included in the model used for predicting suitable areas for invasive pests. [ABSTRACT FROM AUTHOR]

Seagrasses play a vital role in structuring coastal marine ecosystems, but their distributional range and genetic diversity have declined rapidly in recent decades. To improve conservation of seagrass species, it is important to predict how climate change may impact their ranges. Such predictions are typically made with correlative species distribution models (SDMs), which can estimate a species' potential distribution under present and future climatic scenarios given species' presence data and climatic predictor variables. However, these models are typically constructed with species‐level data, and thus ignore intraspecific genetic variability, which can give rise to populations with adaptations to heterogeneous climatic conditions. Here, we explore the link between intraspecific adaptation and niche differentiation in Thalassia hemprichii, a seagrass broadly distributed in the tropical Indo‐Pacific Ocean and a crucial provider of habitat for numerous marine species. By retrieving and re‐analysing microsatellite data from previous studies, we delimited two distinct phylogeographical lineages within the nominal species and found an intermediate level of differentiation in their multidimensional environmental niches, suggesting the possibility for local adaptation. We then compared projections of the species' habitat suitability under climate change scenarios using species‐level and lineage‐level SDMs. In the Central Tropical Indo‐Pacific region, models for both levels predicted considerable range contraction in the future, but the lineage‐level models predicted more severe habitat loss. Importantly, the two modelling approaches predicted opposite patterns of habitat change in the Western Tropical Indo‐Pacific region. Our results highlight the necessity of conserving distinct populations and genetic pools to avoid regional extinction due to climate change and have important implications for guiding future management of seagrasses. [ABSTRACT FROM AUTHOR]

Land‐use/cover change (LUCC) is an important driver of environmental change, occurring at the same time as, and often interacting with, global climate change. Reforestation and deforestation have been critical aspects of LUCC over the past two centuries and are widely studied for their potential to perturb the global carbon cycle. More recently, there has been keen interest in understanding the extent to which reforestation affects terrestrial energy cycling and thus surface temperature directly by altering surface physical properties (e.g., albedo and emissivity) and land–atmosphere energy exchange. The impacts of reforestation on land surface temperature and their mechanisms are relatively well understood in tropical and boreal climates, but the effects of reforestation on warming and/or cooling in temperate zones are less certain. This study is designed to elucidate the biophysical mechanisms that link land cover and surface temperature in temperate ecosystems. To achieve this goal, we used data from six paired eddy‐covariance towers over co‐located forests and grasslands in the temperate eastern United States, where radiation components, latent and sensible heat fluxes, and meteorological conditions were measured. The results show that, at the annual time scale, the surface of the forests is 1–2°C cooler than grasslands, indicating a substantial cooling effect of reforestation. The enhanced latent and sensible heat fluxes of forests have an average cooling effect of −2.5°C, which offsets the net warming effect (+1.5°C) of albedo warming (+2.3°C) and emissivity cooling effect (−0.8°C) associated with surface properties. Additional daytime cooling over forests is driven by local feedbacks to incoming radiation. We further show that the forest cooling effect is most pronounced when land surface temperature is higher, often exceeding −5°C. Our results contribute important observational evidence that reforestation in the temperate zone offers opportunities for local climate mitigation and adaptation. [ABSTRACT FROM AUTHOR]

The response of near ground air temperature to changing precipitation regimes has received extensive attentions in climate change studies. In semi-arid and arid regions, the mean annual temperature correlates negatively with precipitation. However, it remains unclear to what extent one unit change of precipitation can trigger temperature change (i.e., the temperature sensitivity to precipitation). Taking a semi-arid region in Northwest China as a study area, we quantitatively investigated the temperature sensitivity to precipitation change. Further analysis shows that the temperature sensitivity correlates well with the Normalized Difference Vegetation Index (NDVI), indicating that vegetation plays an important role in controlling the long-term temperature sensitivity to precipitation change. Specifically, different land covers show significant differences in temperature sensitivity, with bare soil generally having a higher sensitivity while more densely vegetated areas such as forest and grassland having lower sensitivity values. This implies that vegetation contributes to reducing the temperature sensitivity to precipitation change through the land surface-atmosphere interaction in semi-arid and arid regions. [ABSTRACT FROM AUTHOR]

Little is known about the mechanism of climate–vegetation coverage coupled changes in the Tibetan Plateau (TP) region, which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world. This study, using multisource datasets (including satellite data and meteorological observations and reanalysis data) revealed the mutual feedback mechanisms between changes in climate (temperature and precipitation) and vegetation coverage in recent decades in the Hengduan Mountains Area (HMA) of the southeastern TP and their influences on climate in the downstream region, the Sichuan Basin (SCB). There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA, which is most significant during winter, and then during spring, but insignificant during summer and autumn. Rising temperature significantly enhances local vegetation coverage, and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere. The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure. The high pressure anomaly disperses downstream via the westerly flow, expands across the SCB, and eventually increases the SCB temperature. This effect lasts from winter to the following spring, which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring. These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios, as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. [ABSTRACT FROM AUTHOR]

Global warming has altered the thermodynamic and dynamic environments of climate systems, affecting the biogeochemical processes between the geosphere and atmosphere, which has significant impacts on precipitation extremes and the terrestrial carbon budget of ecosystems. Existing studies have reported a hook structure for precipitation extreme-temperature relationships but have rarely examined the underlying physical mechanisms. Previous studies have also failed to quantify the impact of precipitation on ecosystem productivity, hindering the assessment of future extreme climatic hazards and potential ecosystem risks. To reveal the thermodynamic driving mechanisms for the formation of global precipitation extremes and ecohydrological effects, this study utilizes over ten multisource datasets (i.e., satellite, reanalysis, climate model, land surface model, machine learning reconstruction, and flux tower measurements). We first assess the response of water-heat-carbon flux to precipitation extremes and explain the underlying physical mechanisms behind the hook structures in terms of atmospheric thermodynamics and dynamics. Based on outputs from five global climate models (GCMs) under ISIMIP3b, we project future changes in the hook structures as well as their impacts on precipitation extremes. Finally, we discuss the impact of precipitation on the terrestrial carbon budget by using outputs from the CLM4.5 model. The results show that precipitation extremes are usually accompanied by strong exchanges of water and heat and demonstrate a nonlinear relationship between precipitation and ecosystem productivity. The intensity (duration) of extreme precipitation is intensifying (decreasing) over most areas of the globe, whereas three-dimensional precipitation events are becoming more concentrated. Atmospheric dynamics play a key role in shaping the hook structure. The structure is not stable; it shifts under climate change and is projected to result in a 10–10% intensification in precipitation by the end of this century. Moderate levels of precipitation contribute to carbon assimilation in ecosystems, and the response of the carbon budget to precipitation is relatively stable under climate change. [ABSTRACT FROM AUTHOR]

Sargassum thunbergii is a brown macroalga endemic to the northwest Pacific. It plays important ecological roles in the structure and maintenance of coastal marine ecosystems. The bioactive compounds extracted from S. thunbergii have been extensively documented for potential use in anti-obesity, anti-inflammatory activity, anti-tumor, anti-oxidant and aquacultural drugs. The species is edible and contains relatively high levels of proteins, minerals and several types of amino acids. The present work compiles recently published literature on S. thunbergii, with particular focus on cultivation efforts in China, including the breeding of seedlings and cultivation at sea. A concise review of possible applications is given. Distribution, range shifts associated with past climate change, population genetic structure and connectivity, life history, reproduction and development are all detailed. The review provides important guidelines for future large-scale farming of S. thunbergii. This will help aquaculturalists (phyconomists) to meet the expected increases in demand by industrial users. It will also help to conserve natural populations which may be declining due to destructive harvesting and rapid ocean changes. [ABSTRACT FROM AUTHOR]

The Bohai Bay Basin, located in the eastern North China Block, is an important sedimentary basin for studying the Quaternary climate and environment of northern China. Although sporo-pollen analyses have been used to study the paleoclimate, quantitative research via geochemistry had not been conducted. The sedimentary sequence, geochemistry, and mineralogy of Quaternary sediments from core GJ01 in the Yongding River fluvial plain, northern Bohai Bay Basin, were studied to determine their provenance and investigate climate change during the Quaternary. The stratigraphic sequence of the Quaternary was mainly formed by fluviation by a meandering river, showing a typical dual structure. The sediments have relatively high SiO2 and CaO concentrations, and low Al2O3, Na2O, and Fe2O3T concentrations. In terms of trace elements, most large ion lithophile elements are slightly enriched, and Rb and K concentrations are close to those of post-Archean Australian shale (PAAS); most high field strength elements are slightly to moderately depleted. Rare earth elements (REEs) vary significantly, with light rare earth elements (LREEs) obviously enriched relative to heavy rare earth elements (HREEs). A slightly negative Eu anomaly is present, with nearly no Ce anomaly. Mineralogical analysis shows that the main minerals in the fine-grained sediments are quartz, plagioclase, and K-feldspar. The geochemistry and mineralogy of the sediments indicate that the main provenances were recycled sedimentary rocks and felsic igneous rocks. The sediments have low chemical index of alteration (CIA) values, demonstrating that the source rocks underwent slight weathering. The mean annual precipitation and temperature of the studied area during the Quaternary varied from 531 to 875 mm and from 4.1 to 11.8 °C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Aerodynamic canopy height (ha) is the effective height of vegetation canopy for its influence on atmospheric fluxes and is a key parameter of surface‐atmosphere coupling. However, methods to estimate ha from data are limited. This synthesis evaluates the applicability and robustness of the calculation of ha from eddy covariance momentum‐flux data. At 69 forest sites, annual ha robustly predicted site‐to‐site and year‐to‐year differences in canopy heights (R2 = 0.88, 111 site‐years). At 23 cropland/grassland sites, weekly ha successfully captured the dynamics of vegetation canopies over growing seasons (R2 > 0.70 in 74 site‐years). Our results demonstrate the potential of flux‐derived ha determination for tracking the seasonal, interannual, and/or decadal dynamics of vegetation canopies including growth, harvest, land use change, and disturbance. The large‐scale and time‐varying ha derived from flux networks worldwide provides a new benchmark for regional and global Earth system models and satellite remote sensing of canopy structure. [ABSTRACT FROM AUTHOR]

• An improved Budyko complementary relationship (IBCR) is developed. • The IBCR incorporates effects of both climate change and human activities on basin characteristics. • The IBCR is more flexible than the original relation in separating runoff change. Numerous efforts have been made to separate effects of climate change and human activities on long-term runoff change, including a commonly used method based on the Budyko complementary relationship (BCR) to deal with the non-closure problems often encountered in separating the observed runoff change into its contributed components. The BCR was derived by assuming the change of the Budyko parameter reflecting basin characteristics is related to human activities alone. However, some studies show that basin characteristics are related to both climate change and human activities in certain basins, where applying the BCR method could lead to wrong results. In the study, a more flexible form of the BCR, the improved Budyko complementary relationship (IBCR), is developed under the situation that basin characteristics may relate to climate change. A separation method based on the IBCR is also developed. In this IBCR method, the relationship of the basin characteristics parameter to climate and/or human factors is estimated by using a multi-year moving window. To identify the flexibility of the IBCR method relative to the BCR method, both methods were applied to the Weihe basin of China, whose basin characteristics have been found to be affected by both climate change and human activities. Compared with the IBCR method, the BCR method overestimates the climate effect, while underestimates the human effect on the runoff change in the Weihe basin. It is found that whether or not to incorporate the climate effect into the basin characteristics parameter has a significant impact on the runoff change separation results in Weihe basin. Overall, the IBCR method is more reasonable and flexible for separating the long-term runoff change into different components. [ABSTRACT FROM AUTHOR]