Annual Temperature Research Articles

Recent shift from energy- to moisture-limitation over global croplands

Hot and dry conditions pose a substantial risk to global crops. The frequency of co-occurring heat and drought depends on land–atmosphere coupling, which can be quantified by the correlation between temperature and evapotranspiration (r(T, ET)). We find that the majority of global croplands have experienced declines in r(T, ET) over the past ∼40 years, indicating a shift to a more moisture-limited state. In some regions, especially Europe, the sign of r(T, ET) has flipped from positive to negative, indicating a transition from energy-limitation to moisture-limitation and suggesting a qualitative shift in the local climate regime. We associate stronger declines in r(T, ET) with faster increases in annual maximum temperatures and larger declines in soil moisture and ET during hot days. Our results suggest that shifts towards stronger land–atmosphere coupling have already increased the sensitivity of crop yields to temperature in much of the world by 12%–37%, as hot days are not only hotter, but also more likely to be concurrently dry.

Widening geographic range of Rift Valley fever disease clusters associated with climate change in East Africa

BackgroundRecent epidemiology of Rift Valley fever (RVF) disease in Africa suggests growing frequency and expanding geographic range of small disease clusters in regions that previously had not reported the disease....

A globalized methodology of energy-saving solar greenhouse design in high latitudes

The energy-saving solar greenhouse (ESSG) represents a Chinese-type agricultural building of facilitating low-energy and zero-carbon vegetable overwintering production in high latitudes and cold regions. However, its application benefit outside of China has been limited. To establish an operational ESSG design scheme applicable worldwide, this study developed a comprehensive methodology and specific parameters for different latitudinal regions. The ESSG design was determined based on considerations of daylighting, thermal insulation, heat storage-release capacity, and structural safety. Through validation in six representative regions, the reliability of the ESSG design methodology was confirmed. The optimal design values for front roof angle, ridge height, and back wall height were identified across different latitudes. ESSG in various latitudinal regions from 32°N to 48°N exhibited annual cumulative temperatures could reach 8 × 103∼1.3 × 104°C and accumulated light interception could reach 2 × 1012∼4 × 1012J. Even in the 48°N region, the average internal temperature of the greenhouse exceeded 8 °C, with a nighttime cooling rate lower than 0.75 °C/h and a maximum temperature difference between internal and external environments exceeding 40 °C. This suggests the ESSG fully meets the non-heated overwintering production requirements for common vegetables. The research findings provide crucial theoretical foundations for the global promotion of ESSG, contributing to the reduction of energy consumption and carbon emissions in the sustainable agriculture.

Potential impact of climate change on the distribution of Capricornis milneedwardsii, a vulnerable mammal in China.

Climate change significantly impacted on the survival, development, distribution, and abundance of living organisms. The Chinese serow Capricornis milneedwardsii, known as the "four unlike," is a Class II nationally protected species in China. In this study, we predicted the geographical suitability of C. milneedwardsii under current and future climatic conditions using MaxEnt. The model simulations resulted in area under the receiver operating characteristic curve (AUC) values above 0.9 for both current and future climate scenarios, indicating the excellent performance, high accuracy, and credibility of the MaxEnt model. The results also showed that annual precipitation (Bio12), slope, elevation, and mean temperature of wettest quarter (Bio8) were the key environmental variables affecting the distribution of C. milneedwardsii, with contributions of 31.2%, 26.4%, 11%, and 10.3%, respectively. The moderately and highly suitable habitats were mainly located in the moist area of China, with a total area of 34.56 × 104 and 16.61 × 104 km2, respectively. Under future climate change scenarios, the areas of suitability of C. milneedwardsii showed an increasing trend. The geometric center of the total suitable habitats of C. milneedwardsii would show the trend of northwest expansion and southeast contraction. These findings could provide a theoretical reference for the protection of C. milneedwardsii in the future.

Synergistic impact of climate and land use land cover change dynamics on the hydrological regime of Loktak Lake catchment under CMIP6 scenarios

Study region: Loktak Lake catchment, north-eastern Himalayan ranges, IndiaStudy focus: Assessing the potential synergistic impact of land use land cover (LULC) and climate change on water resources is crucial for watershed management especially in the data-scarce vulnerable wetlands. Using the SWAT hydrological model, the current study seeks to quantify the combined impacts of LULC and climate change on the water balance parameters of the Loktak Lake catchment. This study simulates the hydrological regime of the Loktak Lake catchment based on future climate and changes to LULC dynamics using four GCM models in combination with SWAT models under two alternative scenarios.New hydrological insights for the region: The findings showed that under the SSP 126 and SSP 585 scenarios, the annual mean temperature is anticipated to increase by a maximum of 1.7°C and 3.74°C, respectively, by the 2050 s and 2090 s, while the annual precipitation similarly shown a rising trend for both the scenarios for the mid and far future. The mean annual streamflow is projected to increase by 48.84 cumecs (31.65 %) and 57 cumecs (36.89 %) by the 2050 s and 2090 s decades, respectively, while the water yield will rise by 200.65 mm (30.25 %) and 216.1 mm (32.57 %) in comparable decades. The outcomes of this study might provide a scientific foundation for ecological protection as well as water resource management and development in response to the potential future risk due to climate change in the Loktak Lake catchment.

From vulnerability to vitality: Climate change as a catalyst for economic transformation in small island developing states

As climate change intensifies, its associated risks become increasingly important to societal well-being, with small island developing states (SIDS) being particularly susceptible. The challenges faced by these nations transcend the impacts of their greenhouse gas emissions and cannot be mitigated by emission reduction alone. This paper establishes an innovative, interpretable machine learning model for the first time using import and export data from 1970 to 2020 for nine economically advanced Small Island Developing States, to investigate how economic transformation in small islands occurs against specific climatic contexts and to analyse the impact of these climatic challenges in the process of economic transformation. The study finds that when the average annual temperature exceeds 26 °C over the past two years, or when the sea level rises more than 30 mm, certain islands rapidly complete their economic structural transformation. This indicates that climate change is significantly reshaping the developmental trajectories of these small island economies. To confront these challenges, these states are continuously shifting their developmental focus, reconfiguring their economic structures and growth models to address the ongoing challenges posed by climate change.

The Thermal Equator on Earth and Mars

Abstract The thermal equator (also known as the heat equator) is the circumplanetary set of points that represent the highest mean annual temperature at each longitude. Recent high precision global datasets for Earth and Mars provide a basis for a detailed calculation of the thermal equator on these worlds. On Earth, the temperature values that comprise the thermal equator range from 25.85° to 34.75°C, with a mean of 27.75° ± 1.3°C, and extends in latitude as high as 20°N in Mexico and 29.3°N in the Indian subcontinent. The maximum southern extent is 20°S in Australia. On Mars, lacking oceans, the thermal equator takes a simpler track and is roughly parallel to the equator, and displaced 5°–10°S. However, there is a region of longitude on Mars where the thermal equator becomes bimodal with a northern branch centered at 10°N and a southern branch centered at 20°S.

Spatial patterns and influencing factors of takeaway consumption in 56 cities in China

With the development of the digital economy, the takeaway industry is expanding rapidly. To realize the high-quality development of the takeaway sector, it is necessary to understand the spatial differentiation characteristics of takeaway consumption in Chinese cities and its influencing factors. To this end, we quantitatively studied the spatial distribution of takeaway consumption in 56 cities. We used the number of takeaway orders (copies/person) and the per capita takeaway consumption amount (RMB/person) in major Chinese cities in 2019 to characterize takeaway consumption in China. We investigated the driving mechanisms and factors affecting takeaway consumption amounts per capita and order per capita in China. The results show that takeaway consumption amounts per capita and order per capita is higher in East China than in North and Central China. The tertiary industry population ratio is crucial to takeaway consumption amounts per capita and order per capita in major Chinese cities. Amounts and orders increase as the tertiary industry population ratio rises. Factors affecting takeaway consumption amounts per capita and order per capita in Chinese cities of different population sizes vary. The working-age population ratio heavily influences the takeaway consumption amounts per capita and orders per capita in megacities. Additionally, internet penetration and average annual temperature play a significant role in takeaway consumption amounts per capita and orders per capita in megalopolis. In big cities Ⅰ, the road capacity per capita and GDP per capita are the main factors affecting takeaway consumption amounts per capita and orders per capita. The tertiary industry population ratio is the core factor that determines takeaway consumption amounts per capita and orders per capita in big cities Ⅱ. The interaction between natural and socio-economic factors dramatically increases the impact of takeaway consumption amounts per capita and order per capita in Chinese cities. In conclusion, this study provides a macro-level insight into the spatial characteristics and development factors of takeaway consumption in major Chinese cities. This knowledge is crucial for promoting the takeaway economy's sustainable development and realizing the takeaway industry's green transformation.

Climate and shared evolutionary history drive trait variation among species of Neotropical understory monocots

AbstractEnvironmental variation commonly drives functional trait diversity within species, among species, and across communities. Climate and shared evolutionary history can both influence trait–environment relationships. We studied variation in plant functional traits among closely related Costus species occurring across environmental gradients, the extent to which this variation occurs within single species, and how that variation may be influenced by shared evolutionary history. We measured leaf, aboveground stem, rhizome, and fine root traits of 17 species of Costus in eight sites in Costa Rica and Panama, which varied in elevation, temperature, and precipitation. We then assessed the relationships among traits and environmental variables and estimated the phylogenetic signal of the traits. We observed significant relationships between functional traits and climate. Stomatal conductance decreased, but stem density and rhizome dry matter content increased with decreasing mean annual temperature and precipitation seasonality in both cross‐species and single‐species analyses. This suggests that herbaceous species have a similar trade‐off between plant hydraulic efficiency and safety as found in woody plants. Mean annual temperature was a stronger driver of trait variation than mean annual precipitation. We also found phylogenetic signal in leaf and stem structural traits (i.e., closely related species are more similar than distantly related species), but not in physiological or belowground traits. Our results demonstrate significant trait variation within and among species of Costus, a widespread understory and herbaceous genus in the tropics, which is driven by both climate and shared evolutionary history.

Exploring Climate-Disease Connections in Geopolitical Versus Ecological Regions: The Case of West Nile Virus in the United States.

Many infectious disease forecasting models in the United States (US) are built with data partitioned into geopolitical regions centered on human activity as opposed to regions defined by natural ecosystems; although useful for data collection and intervention, this has the potential to mask biological relationships between the environment and disease. We explored this concept by analyzing the correlations between climate and West Nile virus (WNV) case data aggregated to geopolitical and ecological regions. We compared correlations between minimum, maximum, and mean annual temperature; precipitation; and annual WNV neuroinvasive disease (WNND) case data from 2005 to 2019 when partitioned into (a) climate regions defined by the National Oceanic and Atmospheric Administration (NOAA) and (b) Level I ecoregions defined by the Environmental Protection Agency (EPA). We found that correlations between climate and WNND in NOAA climate regions and EPA ecoregions were often contradictory in both direction and magnitude, with EPA ecoregions more often supporting previously established biological hypotheses and environmental dynamics underlying vector-borne disease transmission. Using ecological regions to examine the relationships between climate and disease cases can enhance the predictive power of forecasts at various scales, motivating a conceptual shift in large-scale analyses from geopolitical frameworks to more ecologically meaningful regions.

Warming Reduces Priming Effect of Soil Organic Carbon Decomposition Along a Subtropical Elevation Gradient

AbstractThe priming effects (PEs) of soil organic carbon (SOC) decomposition is a crucial process affecting the C balance of terrestrial ecosystems. However, there is uncertainty about how PEs will respond to climate warming. In this study, we sampled soils along a subtropical elevation gradient in China and conducted a 126‐day lab‐incubation experiment with and without the addition of 13C‐labeled high‐bioavailability glucose or low‐bioavailability lignin. Based on the mean annual temperature (MAT) of each elevation (9.3–16.4°C), a temperature increase of 4°C was used to explore how PEs mediate the decomposition of SOC in response to warming. Our results showed that the magnitude of glucose‐induced PEs (PEglucose) was higher than lignin‐induced PEs (PElignin), with both PEs linearly increasing with MAT. Across the MAT (i.e., elevation) gradient, short‐term warming had a constant magnitude of negative effects on PEglucose, whereas rising MAT exacerbated the negative effects of short‐term warming on PElignin. Moreover, the temperature sensitivity of SOC decomposition decreased after adding glucose and lignin across the MAT gradient, suggesting that fresh C inputs may prime the microbial breakdown of labile SOC under warming. Taken together, warming alleviated SOC loss due to PEs through varying mechanisms depending on substrate bioavailability. Warming mediated the PEglucose by increasing available nitrogen and weakening microbial nitrogen‐mining but inhibited the PElignin by shifting from microbial nitrogen‐mining to microbial co‐metabolization. Our findings highlight the role of warming in regulating the PEs and suggest that incorporating the suppression effect of warming on PEs can contribute to the accurate prediction of soil C dynamics in a warming world.

Global pattern of organic carbon pools in forest soils.

Understanding the mechanisms of soil organic carbon (SOC) sequestration in forests is vital to ecosystem carbon budgeting and helps gain insight in the functioning and sustainable management of world forests. An explicit knowledge of the mechanisms driving global SOC sequestration in forests is still lacking because of the complex interplays between climate, soil, and forest type in influencing SOC pool size and stability. Based on a synthesis of 1179 observations from 292 studies across global forests, we quantified the relative importance of climate, soil property, and forest type on total SOC content and the specific contents of physical (particulate vs. mineral-associated SOC) and chemical (labile vs. recalcitrant SOC) pools in upper 10 cm mineral soils, as well as SOC stock in the O horizons. The variability in the total SOC content of the mineral soils was better explained by climate (47%-60%) and soil factors (26%-50%) than by NPP (10%-20%). The total SOC content and contents of particulate (POC) and recalcitrant SOC (ROC) of the mineral soils all decreased with increasing mean annual temperature because SOC decomposition overrides the C replenishment under warmer climate. The content of mineral-associated organic carbon (MAOC) was influenced by temperature, which directly affected microbial activity. Additionally, the presence of clay and iron oxides physically protected SOC by forming MAOC. The SOC stock in the O horizons was larger in the temperate zone and Mediterranean regions than in the boreal and sub/tropical zones. Mixed forests had 64% larger SOC pools than either broadleaf or coniferous forests, because of (i) higher productivity and (ii) litter input from different tree species resulting in diversification of molecular composition of SOC and microbial community. While climate, soil, and forest type jointly determine the formation and stability of SOC, climate predominantly controls the global patterns of SOC pools in forest ecosystems.

Responses of Soil C, N, P and Enzyme Activities to Biological Soil Crusts in China: A Meta-Analysis.

Biological soil crusts (BSCs) are often referred to as the "living skin" of arid regions worldwide. Yet, the combined impact of BSCs on soil carbon (C), nitrogen (N), phosphorus (P), and enzyme activities remains not fully understood. This study identified, screened and reviewed 71 out of 2856 literature sources to assess the responses of soil C, N, P and enzyme activity to BSCs through a meta-analysis. The results indicated that BSC presence significantly increased soil C, N, P and soil enzyme activity, and this increasing effect was significantly influenced by the types of BSCs. Results from the overall effect showed that soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), and available phosphorus (AP) increased by 107.88%, 84.52%, 45.43%, 27.46%, and 54.71%, respectively, and four soil enzyme activities (Alkaline Phosphatase, Cellulase, Sucrase, and Urease) increased by 93.65-229.27%. The highest increases in SOC, TN and AN content occurred in the soil covered with lichen crusts and moss crusts, and significant increases in Alkaline Phosphatase and Cellulase were observed in the soil covered with moss crusts and mixed crusts, suggesting that moss crusts can synergistically enhance soil C and N pool and enzyme activity. Additionally, variations in soil C, N, P content, and enzyme activity were observed under different environmental settings, with more pronounced improvements seen in coarse and medium-textured soils compared to fine-textured soils, particularly at a depth of 5 cm from the soil surface. BSCs in desert ecosystems showed more significant increases in SOC, TN, AN, and Alkaline Phosphatase compared to forest and grassland ecosystems. Specifically, BSCs at low altitude (≤500 m) with an annual average rainfall of 0-400 mm and an annual average temperature ≤ 10 °C were the most conducive to improving soil C, N, and P levels. Our results highlight the role of BSCs and their type in increasing soil C, N, P and enzyme activities, with these effects significantly impacted by soil texture, ecosystem type, and climatic conditions. The implications of these findings are crucial for soil enhancement, ecosystem revitalization, windbreak, and sand stabilization efforts in the drylands of China.

Assessment of branched glycerol monoalkyl glycerol tetraether (brGMGT)-based paleothermometry in the 250,000-year sediment record of Lake Chala, equatorial East Africa

Branched glycerol monoalkyl glycerol tetraethers (brGMGTs), a relatively understudied group of bacterial membrane lipids structurally similar to branched glycerol dialkyl glycerol tetraethers (brGDGTs), appear to be strongly influenced by temperature in terrestrial settings. In surficial bottom sediments of East African lakes, the abundance of brGMGTs relative to the sum of brGMGTs and brGDGTs (%brGMGT) and brGMGT distribution are strongly related to local mean annual air temperature (MAAT), stimulating development of new paleothermometers. However, applications of these methods to lake-sediment records are currently lacking. Here we investigate brGMGT concentrations and distributions in 916 samples throughout the 250,000-year (250-kyr) sediment sequence from Lake Chala, a presently fresh and permanently stratified (meromictic) tropical crater lake. All seven previously identified brGMGTs occur abundantly, reflected in a relatively high average %brGMGT of 19%. BrGMGTs and brGDGTs concentrations throughout the sequence are strongly correlated (R = 0.83, p < 0.001), suggesting that their producers and/or associated ecological niches substantially overlap. Clear distinction can be made between brGMGTs produced predominantly in the bottom sediments (H1034a and H1034c) versus the anoxic lower water column (H1020a-c and H1034b). Although a 17-month monitoring study of Lake Chala suggested brGMGTs are primarily produced in the sediments, down-core data assign greater importance to aquatic production than previously estimated. Instead of reflecting temperature, %brGMGT variations showed greatest similarity to GDGT proxies reflecting lake depth and/or mixing regime. BrGMGT-based temperature models produce ambiguous reconstructions, showing little similarity to known global temperature trends or the brGDGT-based mean summer temperature (MST) reconstruction from the same sediments.

The impact of climate and potassium nutrition on crop yields: Insights from a 30-year Swiss long-term fertilization experiment

Climate change will strongly influence agricultural practices in the future. In order to promote resource-efficient agriculture, it is important to analyse the impact of climate variation on crop yields. In this study, we report yields of spring wheat, winter barley, maize, potato and sugar beet from the long-term crop rotation and fertilization experiment Demo in Switzerland and analyze their response to different climate variables (e.g., annual and seasonal temperature, precipitation, evapotranspiration, number of heat days and days of heavy rainfall). In addition, we investigate the impact of readily plant-available soil potassium (K) on the relationship of crop yields and precipitation. Annual and summer temperatures increased by 1 °C and 1.5 °C, respectively, over the observation period, and both the number of heat days and days of heavy rainfall increased in summer. Rising summer temperatures have a negative impact on all crop yields, which was most prominent for spring wheat, potato and maize. Annual, spring and summer precipitation show varying effects on different crops. For maize, soil K has a mediating effect on yield reductions under low spring precipitation. Yields are significantly reduced by 1 t ha−1 per 100 mm reduction of precipitation below a soil K threshold of 7 mg K kg−1 soil. Based on these results and the future climate scenarios for Switzerland, crop rotations with less heat-sensitive species and early-maturing varieties should be considered. In order to keep future irrigation demands and costs as low as possible, the soil K fertility classes in the Swiss K fertilization guidelines might need to be revisited. Our study is one of a few long-term observations that show the impact of climate variation on crop yields and highlights the potential of K management as a climate change adaptation measure.

Modeling terminal Pleistocene and Holocene forager population increase and environmental change in the Central Namib desert, Namibia

This paper examines the interplay of environmental change and human demographic shifts among late Pleistocene and Holocene populations in the hyper-arid context of the Central Namib Gravel plains, Western Namibia. This paper applies a structural equation modeling (SEM) approach to arid-zone hunter-gatherer mobility patterns and settlement systems based on variability among ethnographically and historically observed groups. It then applies this model in examining issues related to the Middle-to-Later Stone Age transition at the sites of Erb Tanks and the Mirabib rock shelter. This model suggests that, among modern arid-zone foragers, population density is by far the strongest factor influencing mobility and settlement systems, with higher population densities favoring longer residential site usages and shorter residential moves within smaller territories. In contrast, environmental variables having to do with annual rainfall, rainfall seasonality, and effective temperature affect mobility and settlement systems in ambiguous and statistically insignificant ways. This paper closes by arguing that regional-scale population increases signaled by various features of Later Stone Age archaeological patterning led to local population expansions in the Central Namib Desert, and that this in turn caused a range of recognizable cultural shifts that were strongly linked with adaptations to aridity.

Predicting the Potential Risk Area of the Invasive Plant Galinsoga parviflora in Tibet Using the MaxEnt Model

The Tibetan plateau, with complex and diverse ecosystems, is an important ecological security barrier to China. However, climate change and the spread of invasive plant species have imperiled the once pristine and diverse ecosystem of the region. To prevent the further spread and control of invasive plants, it is important to delineate the potential distribution patterns of alien invasive plants at the regional scale across Tibet and understand their responses to climate change. Galinsoga parviflora Cav., a member of the family Asteraceae, is an annual herbaceous plant distributed globally as an invasive weed and possesses characteristics that make it highly invasive, such as a strong ability to proliferate and disperse. The species is also known to have an allelopathic effect. There has been no report on the spatial distribution of G. parviflora in Tibet. Using field survey data, we investigated the risk of G. parviflora invasion and its impacts on the ecological safety of Tibet. We employed the MaxEnt model using the R language and SPSS software to optimize and select model parameters and data. We acquired various environmental variables along with current and future climate change scenarios (two carbon emission scenarios, SSP126 and SSP585, for the years 2050 and 2090) to predict the geographic distribution and potential risk areas in Tibet that G. parviflora can invade. The MaxEnt model accurately predicted the distribution of G. parviflora in Tibet with an average AUC of 0.985. The most suitable environmental conditions in which G. parviflora performed the best in Tibet included a mean annual temperature of 6.2–10.0 °C and an elevation range of 2672–3744 m above sea level. Our results indicate that low precipitation during the coldest quarter of the year (mean temperature −2–3 °C) was the most important variable predicting G. parviflora distribution. The results also showed that the species was hardly found when precipitation in the coldest quarter exceeded 155 mm. The current potential invasion risk areas for G. parviflora included the river valleys of central, southeastern, and eastern Tibet. With future climate change scenarios (i.e., SSP126, SSP585), the suitable habitats for G. parviflora distribution will likely shift to northwest regions from the southeast. Particularly under the highest carbon emission scenario (i.e., SSP585), the potential risk area expands more rapidly, and the center of distribution shifts to northwest regions. These findings provide useful information about the current and future changes in G. parviflora distribution in Tibet, which is crucial for the comprehensive and proactive management and control of G. parviflora under future climate change.

Season, size, and sex: factors influencing monogenean prevalence and intensity on Gambusia affinis in New Zealand

A number of studies have been conducted on monogenean seasonality, though primarily in continental regions with wide annual temperatures ranges. We investigated seasonal changes in the prevalence and intensity of Salsuginus seculus infesting sexually dimorphic western mosquitofish (Gambusia affinis) in New Zealand. This represents the first examination of seasonality for this species globally, and the first seasonal assessment of any monogenean population in New Zealand, a temperate country with a mild oceanic climate. Prevalence and intensity of S. seculus with respect to fish size and sex was also examined. Prevalence of S. seculus changed temporally, peaking in summer, and was strongly positively correlated with algal concentrations. This relationship may be associated with increasing food levels, leading to an increase in fish courting and mating, resulting in high numbers and close physical associations of G. affinis individuals, facilitating transmission of the monogeneans. Thus, biotic factors may be important in determining temporal changes in S. seculus prevalence in New Zealand. Female G. affinis had a significantly higher prevalence and mean intensity of S. seculus than males. Longer fish had a higher mean intensity and prevalence of S. seculus. Female G. affinis likely host disproportionately more monogeneans as they are larger than males. Alternatively, females may have a compromised immune response during reproductive periods. Overall, seasonal change was observed in S. seculus prevalence and intensity under New Zealand’s mild climatic conditions, and the larger female G. affinis in this dimorphic species supported a greater prevalence and intensity of infestation than males.

Potential planting regions of Pterocarpus santalinus (Fabaceae) under current and future climate in China based on MaxEnt modeling.

This study modeled the habitat distribution of Pterocarpus santalinus, a valuable rosewood species, across China under current and future climate scenarios (SSPs126, SSPs245, and SSPs585) using MaxEnt. Our findings reveal that the current suitable habitat, spanning approximately 409,600 km2, is primarily located in the central and southern parts of Guangdong, Guangxi, Fujian, and Yunnan, as well as in the Hainan provinces, along with the coastal regions of Taiwan, and the Sichuan-Chongqing border. The habitat's distribution is significantly influenced by climatic factors such as temperature seasonality (bio4), mean temperature of the wettest quarter (bio8), annual mean temperature (bio1), and annual precipitation (bio12), while terrain and soil factors play a lesser role. Under future climate scenarios, the suitable habitat for P. santalinus is projected to expand, with a northeastward shift in its distribution center. This research not only sheds light on the geoecological characteristics and geographical distribution of P. santalinus in China but also offers a scientific basis for planning its cultivation areas and enhancing cultivation efficiency under changing climate conditions.

Local‐Scale Controls Over Leaf N and P Stoichiometry of 121 Plant Species in the Inner Mongolia Grassland

AbstractNitrogen (N) and phosphorus (P) stoichiometry in plant leaves plays an important role in linking plant physiological processes with community assemblage and species distribution. Studies have revealed that temperature is a major driver of leaf stoichiometry, however, whether current global warming will alter leaf N and P stoichiometry on a local scale remain poorly understood. Taking advantage of an unique data set on leaf element concentrations of 122 plant species in the Xilingol Grassland National Reserve (established in 1979), we addressed this issue by resampling plant leaves of the same 121 species in 2018, and compared the leaf N, P, and N:P ratio between the 2 years. We found that leaf N, P, and N:P ratio of the 121 species all exhibited large variation, with a magnitude of 4.5‐fold for N, 5.8‐fold for P, and 6.3‐fold for N:P ratio, respectively. However, the mean leaf N, P, and N:P ratio of the 121 species, as well as for each family, each life form and each habitat type, did not significantly change over 40 years (1979 vs. 2018), though a 2°C increase in annual mean temperature occurred. We identified that taxonomic difference was the primary driver for variations in leaf N, P, and N:P ratio in this grassland reserve, which is different from those on the regional and global scales. These results suggest that controls over leaf stoichiometry are likely scale‐dependent. Thus, using leaf stoichiometry to explain community assemblage and species distribution should take into account the scale‐dependent drivers.