Spatial Risk Assessment Of Potential Illicit Opium Poppy Cultivation

The problem of drug and drug crimes as an essential problem in the non-traditional security field has become a serious challenge faced by the international community.Data-driven drug crime management is a new feature,a new trend,and a new way to improve the country's drug control capabilities.Domestic and foreign anti-drug agencies have used space information technology represented by remote sensing and geographic information systems(GIS)to play an essential role in the detection and governance of illegal cultivation of opium poppy.However,due to the complexity of drug crimes,Anti-drug agencies still need to improve their ability to predict and analyze the potential illicit cultivation risks of regional opium poppy.At the same time,the academic research on the risk assessment of potential illicit cultivation areas of opium poppy is also seriously lagging.At present,relying on limited experience and few research results,it can not provide reliable decision support for the development of drug prevention and control strategies.Therefore,research on the risk assessment of illicit opium poppy cultivation is urgently needed.This thesis aims to improve the ability to predict and analyze the potential illicit cultivation of opium poppy and to help the scientific,precise and efficient treatment of illicit opium poppy cultivation.Through the establishment of an indicator system for the risk assessment of illicit opium poppy cultivation,the research on the ecological environment suitability of poppy plants in China and the evaluation methods for the potential illicit cultivation of opium poppy in suitability growing areas are carried out,thus in theory and practice.We will promote the construction of a crime prevention and control system for the illegal cultivation of drug opium poppy in China.The research contents and main results are as follows:1.Establish an indicator system for potential illicit cultivation risk assessment of opium poppy-based on the perspective of geographic crime.A practical assessment of potential illicit cultivation risks should be based on a sound assessment indicator system design.This study evaluates the individual,environmental and social factors that influence the risk of illicit cultivation of opium poppy from the perspective of geographical crime.Establish a suitable evaluation system for opium poppy in an ecological environment.At the same time,based on the geographical environment combination risk,personal crime risk,social portfolio risk,and other dimensions,establish an indicator system for potential illicit cultivation risk evaluation of poppy.2.Evaluation of suitable growth areas of poppy plants based on a realistic niche model.Through the biological species distribution model,using the distribution data of1,072 poppy plants and 19 environmental variables in China,the environmental variables suitable for the growth of poppy plants were screened to estimate the environmental suitability of poppy plants in China.By applying the maximum entropy(Max Ent)model,the average AUC is 0.825±0.002,which indicates that the Max Ent model has good prediction results for the environmental suitability of poppy plants.This study divides the environmental suitability of poppies into five categories.The model prediction based on the kilometer grid scale shows that in China,from the perspective of the ecological environment,the area suitable for poppy growth is about5,788,000 square kilometers,accounting for the national land.The area ratio is 59.64%.The dominant environmental variables affecting the geographical distribution of poppy plants are annual precipitation,annual average temperature,elevation,land use/coverage,and average monthly temperature difference.In China,the annual average temperature is between 2.7 and 20°C,the annual precipitation is between 300and 1755 mm/year,the altitude is less than 3,000 meters,the average monthly temperature difference is less than 11.5°C,and the cultivated land,woodland,grassland,and rural residential is more suitable for the growth of poppy plants,and the medium and best suitable areas are mainly distributed to the east of the famous geographical boundary line“Hu Huanyong Line”.3.Potential risk assessment of illicit cultivation of poppy in suitable environmental areas based on the random forest model.Based on the publicly obtained cases of illicit opium poppy cultivation from 2000 to 2018,combined with 23 characteristic indicators of environmental risk and social risk,a risk prediction model for illicit opium poppy cultivation based on the random forest was established.The risk of potential illicit cultivation of opium poppy at the national grid scale is predicted.Based on the out-of-bag error(OOB),interpretable variance,coefficient R~2,P-value,and standard deviation,the performance,and accuracy of the model are evaluated.The results show that the application of random forest can achieve high prediction accuracy for illicit planting risk assessment—moreover,good generalization performance.The risk level of illicit cultivation of potential poppy growing areas in China is divided into six categories.According to the evaluation results of the model,the potential illicit planting risk level above intermediate level(including)is 484,500square kilometers,accounting for 5.1%of the national area.The area above the higher risk(inclusive)level accounts for 224,100 square kilometers,accounting for 2.3%of the national area.The high-risk area covers an area of 75,200 square kilometers,accounting for 0.78%of the national area.In terms of spatial distribution,the potential illicit cultivation risk of opium poppy is high in the east and low in the west.The provincial or county border area are high-risk areas where poppy is illegally planted.Among them,the density of attractions,multi-dimensional poverty,poverty risk,population density,road density,terrain roughness,distance from the railway,and suitability of poppy cultivation are the main factors affecting the potential illicit cultivation of opium poppy.The innovation of this thesis includes three aspects.The first is to systematically establish an indicator system for the risk assessment of illicit opium poppy cultivation from the perspective of geographic crime.Secondly,based on the spatial data,the ecological suitability map of poppy plants in China with a spatial resolution of 1km was established.Again,for the first time,based on the environmental and social risk dimension,a potential illicit planting risk distribution map of Chinese regional poppy with a spatial resolution of 1km was established.