Estimating the spatial distribution of environmental suitability for female lung cancer mortality in China based on a novel statistical method.

Lung cancer as one of the major causes of cancer mortality has been demonstrated to be closely related to the ambient atmospheric environment, but little has been done in the synthetic evaluation of the linkage between cancer mortality and combined impact of ambient air pollution and meteorological conditions. The present study determined the environmental suitability for female lung cancer mortality associated with air contaminants and meteorological variables. A novel fuzzy matter-element method was applied to identify the spatial distribution and regions for the environmental suitability for the female lung cancer mortality across China in 2013. The membership functions between the cancer mortality and 6 environmental factors, including PM2.5, NO2, SO2, PM10, the annual mean wind speed, and mean temperature, were generated and the weights of each of the environmental factors were established by the maximum entropy (MaxEnt) model. We categorized the environmental suitability combined with GIS spatial analysis into three zones, including low-suitable, medium-suitable, and high-suitable region where the cancer mortality ranging from low to high rate was identified. These three zones were quantified by the MaxEnt model taking different air pollutants and meteorological variables into consideration. We identified that NO2 was a most significant factor among the 6 environmental factors with the weight of 24.88%, followed by the annual mean wind speed, SO2, and PM2.5. The high-suitable area, mainly in the North China Plain which is a most heavily contaminated region by air pollution in China, covers 1.6195 million square kilometers, accounting for 17.85% of the total area investigated in this study. Identification of the impact of various environmental factors on cancer mortality in the different suitable area provides a scientific basis for the environmental management, risk assessment, and lung cancer control.

[Potential Ecological Suitability Regionalization Analysis of Angelica sinensis Based on GIS and Fuzzy Matter Element Model].

OBJECTIVE: To study the potential ecological suitability regionalization of Angelica sinensis, for protecting wild resources and selecting cultivation location and designing rational production layout. METHODS: Based on fuzzy matter element model, the relationship of fuzzy membership function between ferulic acid content and 14 ecological factors, including climate, topography and soil,were established. Then information entropy theory was used to determine the relative importance of each environmental factor, and thus to determine the most limiting habitat criteria. Finally, the probable spatial distribution of Angelica sinensis across ten provinces in Western China was determined based on GIS spatial analysis of habitat conditions. Meanwhile, the optimal index range of ecological factors was quantified. RESULTS: It was showed that the percentage of moderately and highly suitable habitats for Angelica sinensis in the study area was 9. 64%, its area was 306,768. 01 km2. The moderately and highly suitable habitats were mainly located in the southeast of Gansu ind Tibet,the north of Sichuan and the northwest of Yunnan. The results also showed that six dominant ecological factors controlling the distribution of Angelica sinensis. These six dominant features were as follows: (1) mean temperature of wettest quarter, (2) altitude, (3) precipitation of growth, (4) annual relative humidity, (5) average temperature of growth period, and (6) annual )recipitation. CONCLUSION: The habitat suitability assessment model based on GIS and fuzzy matter element model theory can accurately valuate the habitat suitability of Angelica sinensis, quantify the area of suitable habitat and analyze the spatial distribution. This informaion is of value to provide insight for choosing the most suitable cultivation sites,as well as the habitat protection zones.