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Background and purpose: Native people's encroachment on the forests of the west of the country causes environmental crimes to be committed. Identifying the encroachment and human factors of forest destruction will provide correct management solutions to prevent and reduce the occurrence of environmental crimes. The approval and implementation of effective laws by the government and citizens' compliance with the law will reduce environmental and natural resource crimes. Methodology: In the prospective study, the economic and social factors affecting the change of forest use in Kermanshah province were investigated with respect to 87 legal cases belonging to 76 villages on the outskirts of the Zagros forests during the years 2018 to 2019 using linear modeling and path analysis. According to the level and place of destruction information available in the files, economic and social characteristics as independent variables, or causes, and the level of degraded forest as a dependent variable were investigated using Spearman's rank correlation analysis, multiple linear regression relationship, and path analysis in the form of a structural model. Due to the limited statistical population, all cases were examined without sampling. Due to the legal nature of the cases, only the destroyed surface area and the village where the destruction took place were extracted from these cases. A descriptive report was not provided for the management information received from the economic and executive institutions of the province, and only the relationship between this information and the committed crime was investigated. Results: The correlation of variables showed an increase in the distance between the village and the city, the ratio of light livestock to the population, and the ratio of livestock to the area of agricultural land and natural resources, lack of infrastructure facilities, low non-agricultural economic activity, and a decrease in the per capita ratio of land to population. The decrease in the ratio of irrigated to rainfed agriculture and the decrease in the ratio of heavy livestock to the population has caused the increase in forest destruction. A significant linear regression relationship was observed between the independent variables and the dependent variable, and the variables of the ratio of livestock to agricultural land, non-agricultural economic activity, infrastructure facilities, the ratio of the number of livestock to the area of natural resources, and the distance from the village to the city were entered into the model. It can be said that with the increase of non-agricultural economic activities, the ratio of livestock to the area of agricultural land has decreased and caused the reduction of forest destruction. On the other hand, the positive indirect effect of the ratio of livestock to agricultural land through non-agricultural economic activity on forest destruction was also observed. It seems that in formulating economic plans, environmental considerations are the main condition for protecting natural resources, and the results of this research also showed that the increase and development of non-agricultural economic activities of forest dwellers are important factors in preserving forest lands in Kermanshah province. The development of infrastructure facilities in the village played an important role in reducing the conversion of forest areas to agricultural lands, and it seems that gas supply, development of the electricity network, and the expansion of amenities can play a role in reducing forest destruction. Conclusion: Finally, according to the results obtained from the path analysis, it can be said that keeping more heavy livestock and reducing the number of light livestock will reduce the destruction of forests in Kermanshah province. Also, the development of village infrastructure facilities and non-agricultural economic activities played an important role in reducing the destruction of forest areas. Therefore, in order to reduce the legal cases of forest destruction and prevent criminal behavior in this area, it is better to expand the infrastructure and increase the income of the villagers through non-agricultural economic activities and change the animal husbandry method from traditional to semi-industrial or industrial in order to see a decrease in the entry of such cases at the provincial level. [ABSTRACT FROM AUTHOR]

Activated sludge process is one of the most widely used methods of urban wastewater treatment. The purpose of this study is to use nanobubbles to supply oxygen to the aeration reactor in the activated sludge process and to evaluate its performance in terms of increasing the efficiency of wastewater treatment, reducing energy consumption, reducing the amount of excess sludge and its impact on environmental factors. The results showed that the use of nano-bubble compared to the use of macro-sized bubbles increased the concentration of dissolved oxygen in the aeration reactor up to 3 mg/liter, 18% reduction in energy consumption, 10% reduction in the initial investment in the construction of the wastewater treatment plant. 15% reduction in operating costs of the sewage treatment plant. Increasing the efficiency of removing organic pollutants and reducing the hydraulic retention time in the aeration system, reducing the size of the treatment plant by 10% due to the increase in the efficiency of removing organic substances, and as a result, reducing the hydraulic time and reducing the same amount of land for the construction of the aeration reactor and facilities for the production and distribution of air in the aeration reactor. The presented model, which is obtained by using nano-bubbles in the aeration process of bioreactors, is very effective as a new and innovative technology in preserving, cleaning, and sustaining the environment. [ABSTRACT FROM AUTHOR]