Growing green money? Mapping community currencies for sustainable development

Parallel sustainable monetary systems are being developed by civil society groups and non-governmental organisations (NGOs), informed by ecological economics perspectives on development, value, economic scale and growth, and responding to the unsustainability of current global financial systems. These parallel systems of exchange (or community currencies) are designed to promote sustainable development by localising economic development, building social capital and substituting for material consumption, valuing work which is marginalised in conventional labour markets, and challenging the growth-based monetary system. However, this international movement towards community-based ecological economic practices, is under-researched. This paper presents new empirical evidence from the first international study of the scope and character of community currencies. It identifies the diversity, scale, geography and development trajectory of these initiatives, discusses the implications of these findings for efforts to achieve sustainable development, and identifies future research needs, to help harness the sustainability potential of these initiatives.     

基于DEA模型的长江流域城市生态经济发展分析

DEA模型运用于具有多投入、多产出以及评价对象多元性特征的长江流域城市生态经济发展评价中,能对比不同城市之间生态经济发展的相对有效性。本文运用DEA模型对长江流域6个主要城市的生态经济发展状况进行实证分析,力求做出科学评价并提出有益的发展思路。     

国外低碳经济研究动向分析

进入21世纪,低碳经济成为国内外学者关注热点。首先简要分析经济地理学研究的四个转向:制度转向、文化转向、关系转向和生态转向,探讨低碳经济发展的理论基础,认为低碳经济是区域可持续发展思想、生态文明思想的具体深化,其实质是区域社会经济发展模式的转变。对国外低碳经济研究内容进行总结分析,归纳为不同类型区域碳排放评估预测、不同尺度的能源与碳排放评估模型应用研究、碳补偿机制及其治理研究、低碳经济的政府治理机制、碳税体系研究、碳足迹的界定与评估、低碳城市的发展模式等7个不同方面,在此基础上,对国外低碳经济研究进行了简要评价,认为国外低碳经济研究注重实践研究,研究方法上注重数理模型的应用,但同时存在模型、政策、机制的适应性问题。最后提出对未来低碳经济研究的初步建议:研究设计符合发展中国家国情的区域碳排放评估预测模型,能源与气候变化政策关系模型等数量模型;以多学科、多角度综合集成的视角研究低碳经济对区域发展模式的影响,以及影响的机制及途径。     

Sushi or Fish Fingers? Seafood Diversity,Collapsing Fish Stocks,and Multispecies Fishery Management*

We present a model of a multispecies fishery, and we show the following. (i) Consumer preferences for seafood diversity can trigger a sequential collapse of fish stocks under open‐access fishery. (ii) The stronger the preferences are for diversity, the higher is the need for coordinated multispecies regulation. (iii) Second‐best optimal management of only one (or a few) species is less strict than socially optimal management of the same species. (iv) Myopic regulation of one species, ignoring spillovers to other species, can cause depletion of other stocks that would not be depleted under open access.     

More than total economic value: How to combine economic valuation of biodiversity with ecological resilience

The assessment of total economic value has become a pragmatic and popular approach in nature valuation, yet criticisms have been raised. One major point of critique is that total economic value bases the monetary value of ecosystems purely on the flow of human benefits of services of ecosystems and consequently ignores questions of sustainable use of natural capital per se. This paper explains why total economic value by itself is in principle an inadequate concept to guide sustainable use of ecosystems and gives an overview of essential ecological theory that needs to be taken into account in addition to total economic value to fully include ecosystem sustainability. The paper concludes with a framework for combining ecological theory with economic valuation. The key elements here are theoretical ecological insights about ecosystem resilience and portfolio theory which offers an economic perspective on investment in biodiversity. Portfolio theory puts total economic value in a framework where investment in biodiversity is expanded to cover functional diversity and mobile link species in order to maintain ecosystem resilience and so fosters sustainable use of ecosystems.     

Indirect management of invasive species through bio-controls: A bioeconomic model of salmon and alewife in Lake Michigan

Invasive species are typically viewed as an economic bad because they cause economic and ecological damages, and can be difficult to control. When direct management is limited, another option is indirect management via bio-controls. Here management is directed at the bio-control species population (e.g., supplementing this population through stocking) with the aim that, through ecological interactions, the bio-control species will control the invader. We focus on stocking salmon to control invasive alewives in Lake Michigan. Salmon are valuable to recreational anglers, and alewives are their primary food source in Lake Michigan. We illustrate how stocking salmon can be used to control alewife, while at the same time alewife can be turned from a net economic bad (having a negative shadow value) into a net economic good (having a positive shadow value) by providing valuable ecosystem services that support the recreational fishery. Using optimal control theory, we solve for a stocking program that maximizes social welfare. Optimal stocking results in cyclical dynamics. We link concepts of natural capital and indirect management, population dynamics, non-convexities, and multiple-use species and demonstrate that species interactions are critical to the values that humans derive from ecosystems. This research also provides insight into the management of salmon fisheries in the Great Lakes.     

Bio economic modeling for a sustainable management of biodiversity in agricultural lands

For several decades, significant changes in farmland biodiversity have been reported in Europe. Agriculture is a major driver of these modifications. Taking into account these environmental impacts, agriculture nowadays aims at a more sustainable way of producing which would reconcile its economic and ecological functions. The objective of this paper is to give insights into the impact of public policies on both conservation of biodiversity and farming production. We develop a macro-regional model combining community dynamics of 34 bird species impacted by agricultural land-uses and an economic decision model. The ecological dynamic model is calibrated with the STOC (French Breeding Bird Survey) and AGRESTE (French land-uses) databases while the economic model relies on the gross margins of the FADN (Farm Accountancy Data Network). We investigate the scenario based on subsidies and taxes. We show that simple economic instruments could be used to establish scenarios promoting economic performances and bird populations. It is pointed out how the sustainability of the policies is sensitive to the ecological and economic indicators used by the planner. The bio-economical analysis shows several solutions for the ecology-economy trade-off. These results suggest that many possibilities are available to develop multi-functional sustainable agriculture.     

Spatial welfare economics versus ecological footprint: modeling agglomeration,externalities and trade

A welfare framework for the analysis of the spatial dimensions of sustainability is developed. It covers agglomeration effects, interregional trade, negative environmental externalities, and various land use categories. The model is used to compare rankings of spatial configurations according to evaluations based on social welfare and ecological footprint indicators. Five spatial configurations are considered for this purpose. The exercise is operationalized with the help of a two-region model of the economy, that is, in line with the ‘new economic geography.’ By generating a number of numerical ‘counter-examples,’ it is shown that the footprint method is inconsistent with an approach aimed at maximum social welfare. Unless environmental externalities are such a large problem that they overwhelm all other components of economic well-being, a ‘spatial welfare economic’ approach delivers totally different rankings of alternative land use configurations than the ecological footprint.      

Valuing changes in forest biodiversity

The paper attempts to improve current understanding of the economic value of biodiversity. Instead of the prevailing approach of using only one indicator of biodiversity (typically, species richness) we provide evidence that it is possible to value changes in a number of attributes which describe complex characteristics of biodiversity, based on ecological knowledge. The attributes used include structural, species and functional diversity. The empirical application is a choice experiment study conducted in the Białowieża Forest, Poland: our study is therefore also one of the first to cast light on the value of biodiversity protection in Eastern Europe. Interestingly, respondents valued passive protection regimes resulting in preservation of natural ecological processes. In addition, the respondents seemed to be concerned with the means, and not only the results of protection programmes.     

Putting the "New" into New Trade Theory: Paul Krugman's Nobel Memorial Prize in Economics

This paper reviews the scientific contributions of Paul Krugman to the study of international trade, on the occasion of his receipt of the 2008 Nobel Memorial Prize in Economics. A simplified exposition is presented of some of his principal findings, including: the effects of trade on firm scale and product diversity in a general model of monopolistic competition; the integration of monopolistic competition with factor endowments theory; the implications of transport costs, including home-market effects and the possibility of agglomeration in models of economic geography; and the positive and normative consequences of oligopolistic trade.     

新经济地理理论研究的新进展

新经济地理理论的创始人保罗·克鲁格曼以规模报酬递增而导致的不完全竞争市场结构为假设前提,在一般均衡模型下讨论了空间经济问题,区别于传统经济地理理论,它引发了众多国外学者从理论扩展及实证分析等层面进行深入研究。本文主要从扩大理论菜单、实证研究以及福利与政策研究三个方面入手,着重回顾了20世纪90年代以及21世纪以来的国外学者关于新经济地理理论的研究成果,期望通过对理论研究的梳理,总结和借鉴区域发展的应对政策。     

Economic considerations in the optimal size and number of reserve sites

The debate among ecologists on the optimal number of reserve sites under a fixed maximum total reserve area—the single large or several small (SLOSS) problem—has so far neglected the economic aspects of the problem. This paper argues that economic considerations can affect the optimal number and size of reserve sites and should therefore be taken into consideration in the SLOSS discussion. The paper presents a tractable analytical model to determine the socially optimal number of reserve sites to be allocated in a farming area under a fixed total reserve area, taking the opportunity costs of nature conservation (in this case, agricultural profits) into consideration. Furthermore, the effect of land trade and related transaction costs on the socially optimal number of reserve sites is analyzed. The analysis suggests that in the presence of diminishing returns to farming area, the socially optimal number of reserve sites (which maximizes social welfare) is generally larger than the ecologically optimal number (which maximizes an ecological objective such as population viability). When the opportunity costs of conservation can be offset by land transactions, however, the socially optimal number of reserve sites might be closer to the ecological optimum.     

基于改进的生态足迹模型的石羊河流域生态经济系统分析

基于改进的生态足迹模型,分析了石羊河流域生态经济系统2001～2007年的生态供需状况、可持续发展及发展能力。结果表明,生态盈亏表现为生态赤字,供需矛盾尖锐,生态环境处于不安全状态,但生态赤字缓慢下降,说明生态环境有所改善。同时,可持续发展指标较低,生态-经济处于极不协调的状态,生态足迹多样性指数和发展能力几乎没有变化,石羊河流域实现可持续发展的任务依然艰巨。     

Swidden Agriculture in Developing Countries

Small farmers in many tropical developing countries practice swidden agriculture. A key aspect of swidden agriculture is the time period during which the land is left fallow. This paper uses a new ecological–economic approach to study the fallow period and to determine the optimal length of this period in swidden agriculture. The authors first construct a theoretical model of a parcel of forest land that has been cleared for swidden agriculture. It is then shown how the dynamic and the stochastic properties of this cleared land can be used to derive two objective functions for a small farmer that are ecologically meaningful. Finally, using these two objectives, a probabilistic approach to the determination of the optimal length of the fallow period is discussed. In this approach, the focus of the small farmer is on maintaining the ecological and the economic sustainability of swidden agriculture on the cleared parcel of forest land (CPFL).     

A real option approach to the protection of a habitat dependent endangered species

We use a real option approach to determine when a social planner has to stop or resume logging in situations where an endangered species relies on forest habitat for its survival. Logging affects the stochastic process followed by the habitat of the endangered species, which disappears irreversibly if its habitat reaches a critical extinction level. As long as the endangered species is still in existence, the social planner manages logging in such a way as to balance the risk of extinction against the benefits from commercial wood exploitation. The model incorporates economic, ecological, and social features. It is solved analytically to characterize the optimal forest management rule. Then it is applied to the case of the Rangifer tarandus caribou, an endangered species in Central Labrador (Canada). The parameters of the habitat process are estimated by Monte Carlo methods. The policy implied by the model – alternatively banning and resuming logging according to appropriate habitat threshold levels – turns out to be quite attractive; it does not require long banning periods while it drastically reduces the extinction risk and increases forest value.     

Economic/ecological tradeoffs among ecosystem services and biodiversity conservation

An integrated economic/ecological model is built to address tradeoffs between biodiversity conservation and two marketable rangeland ecosystem services: cattle grazing and elk hunting. The ecology is represented by an eleven species food web in which individual optimizing plants and animals engage in competitive and predator/prey relationships. The ecological model defines a steady-state set of sustainable grazing and hunting options, and for each option, biodiversity is measured using an index defined over the eleven species. In linking the ecology to the economics, social welfare depends on grazing profits and hunter net benefits. The problem can be stated as maximizing economic welfare over two ecosystem services, subject to their sustainable use and subject to a target level of biodiversity. A numerical application with economic and biological data from the Western United States is used to determine sustainable grazing and hunting options for alternative biodiversity levels, and to select the option that maximizes welfare.     

LISREL growth model on direct and indirect effects using cross-country data

Many papers have analyzed the factors affecting economic growth. However, these have concentrated on direct effects and ignored indirect effects through other variables in the model. This study investigates direct and indirect effects of various factors on growth with a causal growth model using LISREL (LInear Structural RELations) for a sample of 105 countries over the period of 1975–2002. Results suggest that ignoring the indirect effects of productivity growth, geography and economic development on economic growth may lead to a considerable underestimation of their ‘true’ total effects on growth. While the importance of the indirect effects of productivity growth and geography relative to their direct effects changes with the estimated model, the relative importance of the indirect effect of economic development on growth is found to be robust to different model specifications.     

Economic geography in the presence of preferential trade agreements: an empirical analysis of OECD data

In the presence of preferential trade agreements (PTAs), there are two distinct levels of economic geography–global economic geography (GEG) between a PTA bloc and the world and local economic geography (LEG) between a PTA member and its PTA bloc. Using OECD data, we empirically examine whether both types of economic geography can help to explain the international production structure. Our findings provide some support for the importance of distinguishing between LEG and GEG when testing for the presence of economic geography.     

Management strategies for tropical rain forests: Results of ecological models and requirements for ecological-economic modelling

In this study, we use two ecological forest models, namely FORMIX3 and FORREG, to analyse the impact of logging on tropical rain forests and to discuss needs for and problems of an economic extension of these models. The FORMIX3 model simulates spatial-temporal dynamics of tropical forests using an individual and process based approach. The main processes included are growth, mortality, competition, and regeneration of trees. The FORREG model simulates wood growth of tropical forests at landscape scale based on differential equations. Regeneration capabilities of logged forests are analysed and compared for different logging strategies. While conventional management strategies with a short logging cycle (here 20 years) produce low yields and cause severe changes in tree species composition, a reduced impact logging strategy with a longer cycle (here 60 years) leads to relatively high yields and causes moderate changes in species composition. Thus, longer logging cycles are preferable from an ecological point of view. However, also economic aspects influence logging decisions, thus a closer analysis of additional economic aspects of forest management is inevitable. We discuss which economic shortcomings of present rain forest models should be dealt with in the future and which additional data is needed as a consequence.