Cicadella viridis (Hemiptera: Cicadellidae) is an omnivorous leafhopper that feeds on plant sap. It significantly reduces the yield of agricultural and forestry crops while feeding or ovipositing on the host plant. In recent years, the rapid expansion of C. viridis has posed a serious threat to agricultural and forestry crops. To study the impact of climate change on the geographical distribution of the leafhopper, the maximum entropy (MaxEnt) model and ArcGIS software, combined with 253 geographic distribution records of the pest and 24 environmental variables, were used, for the first time, to predict the potential distribution of C. viridis in China under conditions of climatic change. The results showed that the currently suitable areas for C. viridis are 29.06–43° N, 65.25–85.15° E, and 93.45–128.85° E, with an estimated area of 11,231,423.79 km², i.e., 11.66% of China. The Loess Plateau, the North China Plain, and the Shandong Peninsula are the main suitable areas. The potential distribution of the leafhopper for the high and medium suitability areas decreased under each climate scenario (except RCP8.5 in the 2090s). Several key variables that have the most significant effect on the distribution of C. viridis were identified, including the mean annual temperature (Bio1), the standard deviation of temperature seasonality (Bio4), the minimum temperature of the coldest month (Bio6), and the precipitation of the coldest quarter (Bio19). Our research provides important guidance for developing effective monitoring and pest control methods for C. viridis, given the predicted challenges of altered pest dynamics related to future climate change.

Climate change has a highly significant impact on the distribution of species. As the greenhouse effect intensifies each year, the distribution of organisms responds to this challenge in diverse ways. Therefore, climatic environmental variables are a key entry point for capturing the current and future distribution trends of pests. Frankliniella occidentalis is an invasive pest attested worldwide. Its damage is mainly divided into two aspects, including mechanical damage caused by its feeding and egg laying and the spread of tomato spotted wilt virus (TSWV). TSWV is the most dominant transmitted virulent disease. Moreover, F. occidentalis is the major vector for the transmission of this virus, which poses a grave threat to the yield and survival of our crops. In this study, the distribution pattern of this pest was explored using 19 bioclimatic variables based on the Maxent model. The results indicated that in the future, high-suitability areas of F. occidentalis will be widely distributed in 19 provinces of China, with Hebei, Henan, Shandong, Tianjin and Yunnan being the most abundant. Among the 19 bioclimatic variables, the five variables of annual mean temperature (Bio 1), temperature seasonality (standard deviation × 100) (Bio 4), min temperature of the coldest month (Bio 6), mean temperature of the driest quarter (Bio 9) and precipitation of the coldest quarter (Bio 19) were selected as the key environmental variables affecting the distribution of F. occidentalis. In summary, temperature and precipitation are vital factors for the study of the species’ distribution, and this study aims to provide new perspectives for the control of this pest in China.

Background: With the growth of economic benefits brought by Zanthoxylum bungeanum Maxim. and the increasing market demand, this species has been widely introduced and cultivated in China. It is important to scientifically select suitable areas for artificial planting and promotion, and to understand the status and potential of Z. bungeanum resources. Results: The maximum entropy (MaxEnt) model and ArcGIS technologies were used to analyze the climatic suitability of Z. bungeanum based on known distribution data, combined with environmental data in China. Z. bungeanum was mainly distributed in subtropical and mid-eastern warm temperate regions. The total suitable area (high and medium suitability) accounted for 32% of China’s total land area, with high suitability areas composing larger percentage, reaching 1.93 × 10⁶ km². The suitable range (and optimum value) of the key environmental variables affecting the distribution of Z. bungeanum were the maximum temperature in February of 2.8–17.7 °C (10.4 °C), the maximum temperature in March of 8.6–21.4 °C (16.3 °C), the maximum temperature in December of 2.5–17.1 °C (9.9 °C), the maximum temperature in November of 7.7–22.2 °C (14.5 °C) and the mean temperature in March of 3.2–16.2 °C (12.0 °C). Conclusions: The model developed by MaxEnt was applicable to explore the environmental suitability of Z. bungeanum.

Essential oils are secondary metabolites in plants with a variety of biological activities. The flavor and quality of Zanthoxylum armatum DC. are mainly determined by the essential oil components in the Chinese prickly ash peels. In this study, the correlation between climate change in different regions and the content of essential oils of Z. armatum was investigated using gas chromatography–mass spectrometry (GC/MS) and multivariate statistical analysis. The Z1–24 refers to 24 batches of samples from different habitats. A total of 145 essential oils were detected in 24 batches of samples, with the highest number of terpene species and the highest content of alcohol. The relative odor activity (ROAV) values identified nine main flavor compounds affecting the odor of Z. armatum. Linalool, decanal, and d-limonene were the most critical main flavor compounds, giving Z. armatum a spicy, floral, oily, and fruity odor. The results of hierarchical cluster analysis (HCA) and principal component analysis (PCA) classified Z5 into a separate group, Z2 and Z7 were clustered into one group, and the rest of the samples were classified into another group. Correlation analysis and path analysis showed that temperature and precipitation were the main climatic factors affecting essential oils. Comparisons can be made with other plants in the genus Zanthoxylum to analyze differences in essential oil type and content. This study contributes to the identification of Z. armatum quality, promotes the accumulation of theories on the effects of climatic factors on essential oils, and enriches the site selection and breeding of Z. armatum under similar climatic conditions.