Prediction of Future Natural Suitable Areas for Rice under Representative Concentration Pathways (RCPs)

Global wheat planting suitability under the 1.5°C and 2°C warming targets

The potential distribution of crops will be impacted by climate change, but there is limited research on potential wheat distributions under specific global warming targets. This study employed the Maxent model to predict the potential distribution of wheat under the 1.5°C and 2°C warming targets based on data from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) multimodel ensemble, and the effect of global warming on wheat planting suitability was analyzed. Our results indicated global warming would significantly change wheat planting suitability. Over half of the areas experienced changes in wheat planting suitability under two warming targets, and the effect became more pronounced with increasing temperatures. Additionally, global warming might promote wheat planting in more regions. The area with an increase in wheat planting suitability was observed to be 9% higher than those experiencing a decrease on average. Moreover, global warming could exacerbate the disparity between global wheat supply and demand in countries/regions. Traditional wheat-producing countries/regions are poised to benefit from the warming effects of climate change, while less developed and wheat import-dependent countries/regions may face greater challenges in achieving wheat self-sufficiency. To address this potential challenge, the promotion and inter-regional exchange of agronomic technologies, and the development of more rational trade standards are urgently needed. Since socioeconomic factors have a significant impact on wheat cultivation, further investigation is required to determine how the wheat planting distribution may change in the future under the combined impact of climate change, supply-demand relationship, and policy.

Integrated drought vulnerability and risk assessment for future scenarios: An indicator based analysis

The dynamic interplay between climate change and socioeconomic development has brought about significant changes in drought hazard, vulnerability, and risk within the global socioeconomic system. However, there is a prevailing lack of understanding about how these changes will manifest in an increasingly globalized economy under global warming. To address this knowledge gap, this study utilizes various climatic, geographical, and socioeconomic data from historical period and future projections to comprehensively map and assess the changes in global drought vulnerability and risk of population in the 2030s and 2050s under the SSP126, SSP245, and SSP585 scenarios. This study finds that the future population at risk of drought is projected to increase by 21.96 % - 25.95 % in the 2030s and 36.64 % - 45.40 % in the 2050s, driven by rapid population growth and substantial changes in drought hazard and vulnerability. This includes varying increases in drought hazard in approximately 58 % of global land area, alongside decreases in drought vulnerability in 50 % - 80 % of global land areas. Most arid and semi-arid regions, including Africa, Central Asia, West Asia, and Australia with less developed economies, are more susceptible to the adverse effects of climate change, leading to significant increases in future drought hazards, vulnerability, and risk, particularly under higher emission scenarios. In contrast, most humid and semi-humid regions exhibit varying degrees of drought vulnerability and risk of population across regions, despite the overall increasing drought hazard, with disproportionate impact of climate change and socioeconomic development. Specifically, projected increases in drought vulnerability and risk are observed in the Amazon, central and western U.S., while decreases are projected in the eastern part of China delimited by the Hu Line, southern India, Japan, Korea, most of Southeast Asia, northern Europe, and South America excluding the Amazon. The eastern U.S. is expected to experience reduced vulnerability but increased drought risk. This study can assist decision makers to develop targeted strategies and measures of adaptation and mitigation in an increasingly globalized economy under global warming.

Identifying potentially contaminated areas with MaxEnt model for petrochemical industry in China

The presence of heavy metal and organic pollutants in wastewater effluents, flue gases, and even solid wastes from petrochemical industries renders improper discharges liable to posing threats to the ecological environment and human health. It is beneficial for pollution control to find out the regional distribution of contaminated sites. This study explored the relationship between the petrochemical contaminated areas and natural, socio-economic, and traffic factors. Ten indicators were selected as input variables, and the MaxEnt model was conducted to identify the potentially contaminated areas. Moreover, among these 10 variables, the factors that have the great impact on the results were determined according to the contribution of variables. The results showed that the MaxEnt model performed well with AUC of 0.981 ± 0.004, and 90% of the measured contaminated sites was located in areas with medium and high probability of contamination in the prediction results. The map of potentially contaminated areas indicated that the areas with high probability of contamination were distributed in Yangtze River Delta, Beijing, Tianjin, southern Guangdong, Fujian coastal areas, central Hubei and northeast Hunan, central Sichuan, and southwest Chongqing. The responses of variables presented that high probability of petrochemical contamination tended to appear in cities with developed economy, dense population, and convenient transportation. This study presents a novel way to identify the potentially contaminated areas for petrochemical sites and provides a theoretical basis to formulate future management strategies.

Prediction of Suitable Future Natural Areas for Highland Barley on the Qinghai-Tibet Plateau under Representative Concentration Pathways (RCPs)

Global climate change, mainly characterized by warming, has resulted in significant migration of temperature-sensitive crops from traditional planting areas, making crops more vulnerable to climate change and natural disasters, increasing yield losses caused by disasters. Based on the MaxEnt model, combining Representative Concentration Pathways 4.5 and 8.5, the potential suitable areas for highland barley planting on the Qinghai-Tibet Plateau were estimated, and the results showed that: (1) Over 30% of the Qinghai-Tibet Plateau is unsuitable for highland barley cultivation, the area of moderately suitable area for highland barley planting is close to 50%, and the marginally suitable and highly suitable area is less than 20%; (2) From the past distribution to the near and medium-term distributions, the unsuitable area for highland barley planting is gradually shrinking. In the moderately suitable area for highland barley planting, some of the area with relatively low suitability was transformed from unsuitable area, and some of the area with relatively high suitability was transformed into marginally suitable area, so that the total area remained basically unchanged. A small part of the marginally suitable area was converted into high-suitability area, which increased the highly suitable area; (3) From the perspective of different scenarios, in the near and medium term, the area with a slight decrease or no change in suitability under RCP 8.5 was smaller than under RCP 4.5, but the area with a significant increase was larger than under RCP 4.5. The areas with a small decrease or no change in suitability accounted for 23.66–33.77% of the total plateau area and were concentrated in the northwestern Qinghai-Tibet Plateau and the Qaidam Basin. Areas with a large increase in suitability accounted for 3.47–15.64% of the total area and were located in the southern, central, and eastern parts of the Qinghai-Tibet Plateau, this area increased significantly with time; (4) Judging from the average altitude change in highland barley planting, the average altitude of the highly suitable area will rise from 3759 m to 3937 m (RCP 4.5) and 3959 m (RCP 8.5) in the near term. By the medium term, the average elevation of the highly suitable area will increase from 3759 m to 4017 m (RCP 4.5) and 4090 m (RCP 8.5). The trend of rising average altitude continues to strengthen.