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A MATHEMATICAL MODEL FOR THE DEPLETION OF FORESTRY RESOURCES DUE TO population AND population pressure AUGMENTED INDUSTRIALIZATION

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第1期5卷 186-201页

作者： A.K.MISRA KUSUM LATA J.B.SHUKLA Department of Mathematics Faculty of Science Banaras Hindu UniversityVaranasi-221005India BIT BIIFR&DBhabha Group of Institutions Kanpur(Rural)-209204India

In this paper,a nonlinear mathematical model is proposed and analyzed to study the depletion of forestry resources caused simultaneously by population and population pressure augmented *** control of population pressure,using economic efforts is also considered in the modeling *** is assumed that cumulative biomass density of forestry resources and the density of population follow logistic *** is further assumed that the density of population and the level of industrialization increase as the cumulative biomass density of forestry resources *** cumulative density of economic efforts,which are applied to control the population pressure,is considered to be proportional to the population *** model analysis shows that as the population pressure increases,the level of industrialization increases leading to decrease in the cumulative biomass density of forestry *** is found that if population pressure is controlled by using some economic efforts,the decrease in cumulative biomass density of forestry resources can be made much less than the case when no control is *** is also noted that if the population pressure augmented industrialization increases without control,the forestry resources may become extinct.

关键词： Mathematical model forestry resources population pressure industrialization economic efforts stability

population pressure: When Will It End?

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China population Today 2002年第Z1期19卷 4-5页

Migration for survival under natural disasters:A reluctant and passive choice for agriculturalists in historical China

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Science China Earth Sciences 2017年第12期60卷 2089-2096页

作者： PEI Qing Department of Social Sciences the Education University of Hong KongHong KongChina

This study quantitatively investigates the long-term dynamics of the association between natural disasters and the migration of agriculturists in historical China. population pressure is also studied because migration is a population density-dependent phenomenon. This study has adopted correlation analysis, multivariate linear/Poisson regression analyses, and Granger causality analysis to verify the linkages of natural disaster-migration and population-migration in historical China by collecting updated datasets. This study is the first attempt to reveal that the duration effects of natural disasters on the migration of agriculturalists are short-term and almost instantaneous. Although the agrarian society has a low buffering capacity, the effects of natural disasters within a short-term scale could be relieved to some extent. However, population pressure can push migration on a long-term scale despite its limited forcefulness.

关键词： Natural disasters Agriculturalists'migration population pressure Empirical analysis Historical China

Relief Degree of Land Surface and population Distribution of Mountainous Areas in China

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Journal of Mountain Science 2015年第2期12卷 518-532页

作者： LIU Ying DENG Wei SONG Xue-qian Institute of Mountain Hazards and Environment Chinese Academy of Science University of Chinese Academy of Science Chengdu University of Information Technology

Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(ppopulation density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(

关键词： Land surface Relief degree population density population pressure population distribution Mountain China

Modeling the effects of environmental pollution intensified by urbanization on human population

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 74-86页

作者： Abhinav Tandon Kumari Jyotsna Department of Mathematics Birla Institute of Technology(BIT)Mesra Ranchi-835215JharkhandIndia

A mathematical model is presented here to investigate the effects of environmental pollution,intensified by urbanization,on the density of human ***,urbanization is assumed to grow with constant rate and also,induced through growing population and the corresponding population *** model analysis,qualitatively and numerically,show that though the growth of population or population pressure is responsible for the growing urbanization,but for very large increase of urbanization,the population may not survive in the long run due to environmental pollution driven by urbanization.

关键词： Pollution population urbanization population pressure stability numerical analysis

Social buffer or avoidance depends on the similarity of stress between queen ants

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Current Zoology 2023年第2期69卷 181-191页

作者： Iago Sanmartin-Villar Universidade de Vigo ECOEVO LabEscola de Enxenaria ForestalCampus Universitario A Xunqueira36005 PontevedraGalizaSpain

The association of unrelated ant queens(pleometrosis)is supposed to improve nest foundation and competitiveness under environmental stress,but its evolutionary maintenance is difficult to explain because only one of the queens survives after nest *** aim was to test the potential effect of queen association as a social buffer,that is,as a mechanism reducing stress and improving fitness due to the benefits of social contact.I analyzed the survival,fecundity,and behavior of isolated and paired Lasius flavus queens exposed and not exposed to stressors(disturbing environmental conditions).I found no difference in survivorship between isolated and paired queens or between stressed and unstressed isolated *** in which 1 or 2 paired queens were stressed showed higher *** queens died similarly to their stressed nestmates,suggesting stress transmission.A trend suggested that paired queens produced eggs more quickly,but eggs were produced similarly between isolated and paired *** avoidance was observed in groups with 1 stressed and 1 unstressed ***,the groups with 2 stressed queens showed the expected behaviors according to social buffering:lower mobility and more interindividual *** findings suggest the synergistic effect of pleometrosis and stress and the dependence of stress level similarity between nestmates on social buffering or rejection on ant queens.

关键词： fitness haplometrosis population pressure reproductive strategy social insects

Application of Remote Sensing and GIS Technology to the Study of Desertification of Arable Lands in North Shaanxi, China

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Geo-Spatial Information Science 2004年第3期7卷 187-192页

作者： MushtakTalibJabbar HUGuangdao ZHANGZhenfei ChinaUniversityofGeosciences.31LumoRoad Wuhan430074China. 不详

The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665.985 km 2 during the period 1987\|1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground\|based methods for such surveys. The multi\|scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year.

关键词： urbanization population pressure arable land desertification remotesensing GIS

江南道路、温州模式与过密化理论的误算——对经济史研究中人口压力说的检讨

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Environmental Change in Agricultural Land in Southwest Cote d’Ivoire:Driving Forces and Impacts

经济史 2018年第3期 76-83页

作者：张宁

过密化理论是人口压力说的代表，认为人口因素是东西方大分流的重要原因，由于低工资阻碍了资本积累和技术创新，人口过剩使中国从14世纪中叶以后逐渐陷入贫困化和劳动密集型经济。这一观点试图以新古典经济学的资本—劳动替代理论去解... 详细信息

过密化理论是人口压力说的代表，认为人口因素是东西方大分流的重要原因，由于低工资阻碍了资本积累和技术创新，人口过剩使中国从14世纪中叶以后逐渐陷入贫困化和劳动密集型经济。这一观点试图以新古典经济学的资本—劳动替代理论去解释长期历史变迁，忽视了工业革命前东西方经济的相似之处，以简单教条的方式看待经济技术变革与人口因素之间复杂多变的关系，对产权制度创新和资源禀赋的关键作用估计不足。因此，既看不到英格兰模式的特殊性，又刻意低估了江南道路的特色和成就，而且潜藏着反市场经济的逻辑，不承认人口密集的地区能走出自下而上的工业化道路，表现为对民国时期乡村工业化经验的贬低，以及对改革开放后温州模式的错误预言。作为典型的欧洲中心主义史观，人口压力说对中国传统社会的人口和生育模式持有文化偏见，而且过度夸大人口密度对经济的影响，未能充分考虑其他社会和自然因素影响下的相对人口压力。

关键词：人口压力工业革命江南道路英格兰模式温州模式 population pressure Industrial Revolution Jiangnan(江南) Path English Mode Wenzhou(温州)Mode

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Journal of Environmental Protection 2013年第12期4卷 1373-1382页

作者： A.Y.N’go J.T.Ama-Abina A.Z.Kouadio H.K.Kouassi I.Savane Nangui Abrogoua University Environmental and Geosciences LaboratoryCote d’Ivoire Jean Lorougnon Guede University of Daloa Cote d’Ivoire

Environmental conditions change in the Southwest of Cote d’Ivoire has been a major issue in development debates over the last decades. Using remote sensing based on land cover change analysis, climatic data, national statistical data, we analyzed the drivers of environmental change in Southwestern of Cote d’Ivoire. Being part of the perennial crops basin, Southwestern of Cote d’Ivoire has witnessed rapid degradation of environmental conditions caused by the conversion of forest areas to agricultural land during the last 20 - 30 years and by a combination of decline in precipitation, soil degradation, a diversity of policies with little concern for the environment and population pressure. We concluded that while climate variability has influenced environmental change in the area of Sassandra, various types of anthropogenic and State interventions in agriculture appear to have been the main underlying causes of environmental degradation.

关键词： Land Use Climate Variability Environmental Change population pressure Sassandra Cote d’Ivoire