Analysis on the Spatio-Temporal Changes of Sustainable Land Use in Tibet

By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment, economic development, resources and social advancement, this article studies the following contents respectively in two dimensions of time and space： the changes of sustainable land use of Tibet in recent 20 years and spatial characteristics of sustainable land use of Tibet in 2002. The following conclusions can be drawn from evaluation results .① With regard to com- prehensive evaluation value of sustainable land use, the trend of Tibet sustainable land use evaluation values from 1983 to 2002 are very close to the comprehensive evaluation values of ecological environment, which is up trend; ② sustainable utilization degree of land use in eastern region of Tibet is much higher than that of western region. ③ the sustainable land use evaluation value of Nyingtri County is the highest, and the counties with relatively higher land sustainable use values include Lhasa, Lhoka, Chamdo. While Nakchu, Ngari, Shigatse counties have the relatively lower evaluation values; ④ By analyzing each evaluation indicator＇s weight on sustainable land use, it can be concluded that the key limiting factors of sustainable Tibet land resource utilization are land desertification, grassland degradation and low economic level.

Is There a Trade-off Between Freedom and Safety?A Philosophical Contribution to a Covid-19 Related Discussion

The aim of the present paper is to critically discuss the common claim that in times of the Covid-19 pandemic there is a trade-off between freedom and safety when it comes to measures taken by authorities to ban the virus.In order to approach the question of whether or not this claim is justified a distinction is made between a more or less common economic view of reality and a philosophical interrogation of the assumptions underlying economic reality.Thus,the paper provides two insights.First,that the economic concept of trade-off is not appropriate for a reflection on freedom and human dignity.Second,in the light of classical philosophical notions of freedom,the implicit or explicit understanding of freedom in the economic domain turns out to be insufficient.This is why the paper argues that the perception of the mentioned trade-off as such is already a severe,albeit inconspicuous,threat of freedom.

Inflation and Unemployment Trade-off:Is Phillips Curve True for African Developing Countries?Evidence from Sudan

The relationship between wage inflation and unemployment(Phillips Curve)is controversial in economic thought,and the controversy is centered around whether there is always a trade-off or not.If this relati-onship is negative it is called The short-run Fillips Curve.However,in the long run,this relationship may probable not exist.The matter of how inflation and unemployment influence economic growth,is debatably among macroeconomic policymakers.This study examines the behavior of the Phillips Curve in Sudan and its effect on economic growth.

China＇s economic development stage and its spatiotemporal evolution： A prefectural-level analysis

As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China＇s economy. However, little research has grasped the essence of the economic development stage and the spatio-temporal evolution process at the prefecture level; this may lead to biased policies and their ineffective implementations. Based on Chenery＇s economic development theory, this paper identifies China＇s economic development stages at both national and prefectural levels. Both the Global Moran I index and the Getis-Ord Gi＊ index are employed to investigate the spatio-temporal evolution of China＇s economic development from 1990 to 2010. Major conclusions can be drawn as follows. （1） China＇s economic development is generally in the state of agglomeration. It entered the Primary Production Stage in 1990, and the Middle Industrialized Stage in 2010, with a ＇balanced-unbalanced-gradually rebalanced＇ pattern in the process. （2） China＇s rapid economic growth experienced a spatial shift from the coastal areas to the the inland areas. Most advanced cities in mid-western China can be roughly categorized into regional hub cities and resource-dependent cities. （3） Hot spots in China＇s economy moved northward and westward. The interactions between cities and prefectures became weaker in Eastern China, while cities and prefectures in Central and Western China were still at the stage of individual development, with limited effect on the surrounding cities. （4） While the overall growth rate of China＇s economy has gradually slowed down during the past two decades, the growth rate of cities and prefectures in Central and Western China was much faster than those in coastal areas. （5） Areas rich in resources, such as Xinjiang and Inner Mongolia, have become the new hot spots of economic growth in recent years. For these regions, however, more attention needs to be paid to their unbalanced industrial structures and the lagging social development against the backdrop of the rapid economic growth, driven predominantly by the exploitation of resources.

Agricultural labor changes and agricultural economic development in China and their implications for rural vitalization

Based on panel data from 1991, 2000 and 2010 at the county level in China, this study analyzed the coupling characteristics and spatio-temporal patterns of agricultural labor changes and economic development under rapid urbanization using quantitative and GIS spatial analysis methods. Three primary conclusions were obtained.(1) During 1991–2010, China's agricultural labor at the county level showed a decreasing trend, down 4.91% from 1991 to 2000 and 15.50% from 2000 to 2010. In spatial distribution, agricultural labor force has evolved by decreasing eastward and increasing westward.(2) During 1991–2010, China's agricultural economy at the county level showed a sustained growth trend, with a total increase of 140.13%, but with clear regional differences. The proportion of agricultural output in national GDP gradually decreased, characterized by decreases in eastern China and increases in western China.(3) The coupling types of economic-labor elasticity coefficient are mainly growth in northwest China, for both the agricultural economy and labor, and are intensive in southeast China, with growth of the agricultural economy and reduction of agricultural labor. Regions with lagged, fading, and declining coupling types are generally coincident with the high incidence of poverty in China. However, different coupling types had a positive developing trend for 1991–2010. Finally, based on the coupling types and spatial distribution characteristics of economic-labor elasticity coefficients, some policy suggestions are proposed to promote the integration of the primary, secondary, and tertiary industries and the vitalization of rural economies.

Step-wise synthesis of work exchange networks involving heat integration based on the transshipment model

Due to the deterioration of serious energy dilemma,energy-conservation and emission–reduction have been the strategic target in the past decades,thus people have identified the vital importance of higher energy efficiency and the influence of lower carbon development.Since work exchange network is a significant part of energy recovery system,its optima design will have dramatically significant effect on energy consumption reduction in chemical process system.With an extension of the developed transshipment model in isothermal process,a novel step-wise methodology for synthesis of direct work exchange network(WEN)in adiabatic process involving heat integration is first proposed in this paper,where a nonlinear programming(NLP)model is formulated by regarding the minimum utility consumption as objective function and optimizing the initial WEN in accordance with the presented matching rules to get the optimized WEN configuration at first.Furthermore,we focus on the work exchange network synthesis with heat integration to attain the minimal total annual cost(TAC)with the introduction of heat-exchange equipment that is achieved by the following strategies in sequence:introducing heat-exchange equipment directly,adjusting the work quantity of the adjacent utility compressors or expanders,and approximating upper/lower pressure limits consequently to obtain considerable cost savings of expanders or compressors and work utility.Finally,a case taken from the literature is studied to illustrate the feasibility and effectiveness of the proposed method.

Path of Rural Sustainable Development Based on the Evolution and Interaction of Rural Functions:A Case Study of Chongqing Municipality,China

In order to investigate the evolutionary characteristics of rural functions and their interaction,37 districts and counties in Chongqing,China are used as research objects to measure the level of rural functions and analyze the interaction between rural functions using entropy value method and spatial autocorrelation method.The results show that from 2009 to 2019,the three main functions of production,living and ecology in Chongqing’s villages have been greatly enhanced,especially the production function.On the whole,the production and living functions are stronger in the western part,while the ecological functions are significant in the eastern and southern parts of Chongqing,with some differences in local spatial characteristics.This finding is consistent with the regional economic and social development of Chongqing.In addition,the interaction between rural functions is also evident.In general,production and living functions are mainly expressed in synergistic relationships.Ecological and production functions,including ecological and subsistence functions,mainly present a trade-off relationship.The interactions between rural functions also show clear spatial and temporal differences.In addition,different regions have different comparative advantage functions,and in this study,the counties of Chongqing are classified into four types.Policy makers are advised to adopt different measures according to the different types to promote sustainable rural development by coordinating the’production-living-ecological’functions of rural areas.This study reveals the spatio-temporal evolution of rural functions and the interaction between rural functions,which can provide theoretical support and practical reference for rural revitalisation and sustainable development.

Linking ecosystem services and economic development for optimizing land use change in the poverty areas

For the sustainable development of human beings and society,it is important to conserve the ecosystems and alleviate poverty in the low agricultural productivity or ecologically vulnerable areas.To avoid the decrease in ecosystem services(ES)under the effects associated with reducing poverty,we need to carefully consider the relationship between land use changes and the economic development in economically poor areas.We selected the Lingqiu County as our study area,which is a national impoverished county in China,and analyzed the impact of poverty alleviation efforts on the ecological and economic sustainability in the region through ES evaluation.The results showed that land use change in the Lingqiu County has not changed the ES significantly during 2007-2016.The gross domestic product(GDP)growth rate(15.81%)during 2001-2016,indicates the effectiveness of the poverty alleviation efforts implemented.The rise in the index of ecological and economic relationship during 2001-2016(from 0.2389 to 0.3629)maintains in a harmonious coordination situation.Presently,the value of ES has not been converted to market-based benefits,and therefore,it is indispensable to find a marketplace for ES(in an innovative way)to promote the high-quality sustainable development of a local economy.

Optimizing water resources allocation in the Haihe River basin under groundwater sustainability constraints

This study applies a hydroeconomic optimization method for water resources management in the highly water stressed Haihe River basin. A multi-objective, multi-temporal deterministic hydroeconomic optimization model has been built to quantify the economic trade-offs and reveal "minimum cost strategies" when reducing groundwater abstraction to sustainable levels. A complex basin representation, with ～140,000 decision variables is formulated where each decision variable represents a flow-path from a water source to a sink. Available water sources are runoff generated by the sub-basins upstream the nine major surface water reservoirs, the inter-basin transfers from Yellow River and South to North Water Transfer Project(SNWTP) and the natural groundwater recharge to the three main groundwater aquifers. Water demands, i.e. sinks, are aggregated for each model sub-basin in categories of the major agricultural users, domestic, industrial and ecological water demands. Each demand is associated with a curtailment cost and groundwater abstraction with a pumping cost. Groundwater overdraft is constrained in each model scenario, ranging from unlimited overdraft in the plain area groundwater aquifer to sustainable abstractions over an 8-year period. Inflow upstream Yuqiao reservoir, and the inter-basin transfers from SNWTP and Yellow River are identified as the water resources with the highest increase in average shadow prices when limiting groundwater overdraft. An increase in inflow shadow prices of 37.5% indicates that these water sources will be most valuable if sustainable groundwater abstraction should be achieved. The shadow prices of water sources reveal when and where in the Haihe River basin users are curtailed if water resources are managed in the most optimal way. Average shadow prices of 1.6 yuan/m3 for all surface water sources in the sustainable abstraction scenarios shows that overdraft can be avoided by curtailment of users with a willingness-to-pay ≤1.6 yuan/m3. The shadow prices of the existing surface water res-ervoirs represented in the model shows that no costs can be saved from expanding their capacities. Finally, the cost of achieving sustainable groundwater abstraction with present water resource availability is found to be minimum 8.2 billion yuan/year.