Ecological footprint of food consumption in China：1982-2004

This paper calculates the land （including water area） requirement for food consumption in both balanced andactual diet in China by ecological footprint analysis. To determine whether logical and actual food demands are withinnatural regenerative ability, carrying capacity （excluding forestry production） is also calculated. Results show that actualdiet patterns were ecologically friendly in the period of 1982-2004 in China, mainly because of the rural moderate dietpatterns. But actual per capita footprint already overran its corresponding logic value of 0.976ha in urban areas in 2002.Productive areas for food production can satisfy the land requirement for actual diet patterns during the researchingperiod in China, nevertheless cannot satisfy that for balanced diet pattern or solve the problem of unbalanced ecologicalfootprint. The continual rising ecological footprint of food consumption in both rural and urban areas indicates that percapita footprint will keep on increasing in China and even may be more than the suggested logic value if no relevantcountermeasures are made to regulate diet patterns. Strictly speaking, China is facing food shortage, both in quality andin quantity.     

国内外水资源承载力的研究综述

随着能源危机的出现,资源环境问题逐渐成为各国经济学家和环境学家特别关注的问题.近年来,水资源短缺越来越成为各地经济发展的制约因素,面对这种情况,资源承载力概念的提出为资源与经济发展问题提供了一条新的研究途径.本文将国内外有关水资源承载力概念和量化方法的研究作一总体分析,结果表明:(1)国外对水资源承载力的研究较少,国内的研究大体可分为初始、发展、鼎盛和拓展四个阶段;(2)从横向比较来看,水资源承载力的研究在我国以近十年为盛.但研究多集中在资源学科领域和地理环境学科领域,角度大多是综合考虑多方面的影响因素,对一个地区的水资源承载力作出系统评价,并借助可持续发展的思想,应用已有的和创新的方法来解决水资源承载力的问题;(3)水资源承载力的研究在一定程度上是土地资源承载力研究的进步;(4)水资源承载力的研究较少考虑环境污染对水资源承载力以及整个社会系统的影响.在此基础上,本文最后对承载力在自然资源方面的研究作了小结和展望.     

The blue, green and grey water footprint of rice from production and consumption perspectives

The paper makes a global assessment of the green, blue and grey water footprint of rice, using a higher spatial resolution and local data on actual irrigation. The national water footprint of rice production and consumption is estimated using international trade and domestic production data. The global water footprint of rice production is 784 km³/year with an average of 1325 m³/t which is 48% green, 44% blue, and 8% grey. There is also 1025 m³/t of percolation in rice production. The ratio of green to blue water varies greatly over time and space. In India, Indonesia, Vietnam, Thailand, Myanmar and the Philippines, the green water fraction is substantially larger than the blue one, whereas in the USA and Pakistan the blue water footprint is 4 times more than the green component. The virtual water flows related to international rice trade was 31 km³/year. The consumption of rice products in the EU27 is responsible for the annual evaporation of 2279 Mm³ of water and polluted return flows of 178 Mm³ around the globe, mainly in India, Thailand, the USA and Pakistan. The water footprint of rice consumption creates relatively low stress on the water resources in India compared to that in the USA and Pakistan.     

The water footprint of coffee and tea consumption in the Netherlands

A cup of coffee or tea in our hand means manifold consumption of water at the production location. The objective of this study is to assess the global water footprint of the Dutch society in relation to its coffee and tea consumption. The calculation is carried out based on the crop water requirements in the major coffee and tea exporting countries and the water requirements in the subsequent processing steps. In total, the world population requires about 140 billion cubic metres of water per year in order to be able to drink coffee and tea. The standard cup of coffee and tea in the Netherlands costs about 140 l and 34 l of water respectively. The largest portions of these volumes are attributable to growing the plants. The Dutch people account for 2.4% of the world coffee consumption. The total water footprint of Dutch coffee and tea consumption amounts to 2.7 billion cubic metres of water per year (37% of the annual Meuse runoff). The water needed to drink coffee or tea in the Netherlands is not Dutch water. The most important sources for the Dutch coffee are Brazil and Colombia and for the Dutch tea Indonesia, China and Sri Lanka. The major volume of water to grow the coffee plant comes from rainwater. For the overall water need in coffee production, it makes hardly any difference whether the dry or wet production process is applied, because the water used in the wet production process is a very small fraction (0.34%) of the water used to grow the coffee plant. However, the impact of this relatively small amount of water is often significant. First, it is blue water (abstracted from surface and ground water), which is sometimes scarcely available. Second, the wastewater generated in the wet production process is often heavily polluted.     

我国省域水资源的可持续利用初探*——以辽宁山东等省供水量指标为基础数据

水资源承载力的确定是经济可持续发展决策的前提。本文通过相对水资源承载力的动态分析方法,透析辽宁、山东等省份水资源短缺和超负载的现状,揭示可控因子,进而提出水资源可持续利用的对策。     

The water footprint of energy from biomass: A quantitative assessment and consequences of an increasing share of bio-energy in energy supply

This paper assesses the water footprint (WF) of different primary energy carriers derived from biomass expressed as the amount of water consumed to produce a unit of energy (m³/GJ). The paper observes large differences among the WFs for specific types of primary bio-energy carriers. The WF depends on crop type, agricultural production system and climate. The WF of average bio-energy carriers grown in the Netherlands is 24 m³/GJ, in the US 58 m³/GJ, in Brazil 61 m³/GJ, and in Zimbabwe 143 m³/GJ. The WF of bio-energy is much larger than the WF of fossil energy. For the fossil energy carriers, the WF increases in the following order: uranium (0.1 m³/GJ), natural gas (0.1 m³/GJ), coal (0.2 m³/GJ), and finally crude oil (1.1 m³/GJ). Renewable energy carriers show large differences in their WF. The WF for wind energy is negligible, for solar thermal energy 0.3 m³/GJ, but for hydropower 22 m³/GJ. Based on the average per capita energy use in western societies (100 GJ/capita/year), a mix from coal, crude oil, natural gas and uranium requires about 35 m³/capita/year. If the same amount of energy is generated through the growth of biomass in a high productive agricultural system, as applied in the Netherlands, the WF is 2420 m³. The WF of biomass is 70 to 400 times larger than the WF of the other primary energy carriers (excluding hydropower). The trend towards larger energy use in combination with an increasing contribution of energy from biomass will enlarge the need for fresh water. This causes competition with other claims, such as water for food.     

Sustainability of nations by indices: Comparative study between environmental sustainability index, ecological footprint and the emergy performance indices

The present work makes a comparison between the two most used environmental sustainability indices of nations: “ecological footprint” and “environmental sustainability index”, with two emergy ratios (renewability and emergy sustainability index). All of them are gaining space within the scientific community and government officials. Despite the efforts for obtaining an index that adequately represents the sustainability of a region, according to the result of this research, nowadays there is not yet a completely satisfactory index. We consider that all of them need to be improved, but the results point out the possibility of obtaining one better index of sustainability through the junction of ecological footprint with renewability emergy index.     

Using the concept of yield to assess the sustainability of different tourist types

Sustainability assessments have become important tools for decision makers. This research assesses the sustainability of different types of tourists in New Zealand by using the concept of yield and by developing yield indicators in the areas of financial, public sector and sustainable yield. The concept and indicators have been developed in cooperation with the New Zealand tourism sector and therefore provide a sector-driven approach to implement a sustainability assessment. The analysis shows that there are numerous ‘trade-offs’ between indicators when attempting to define the ‘ideal visitor type’. Coach tourists, for example, are the largest spenders and generate the greatest Value Added in tourism on a per-day basis, but they contribute less to the financial sustainability of tourism when the costs of capital are accounted for. Coach tourists are highly concentrated in a few key destinations and at the same time produce substantial amounts of CO₂ emissions due to their air travel component. In contrast, backpacker and camping tourists provide greater financial yield and are more dispersed, but they are also the greatest user of publicly provided tourist attractions and therefore come at a higher cost to government than other tourist types. Camping tourists are also contributing considerably to CO₂ emissions. The yield analysis proposed in this paper could be a valuable tool for complex policy decision making and identifying strategies that lead to high-yield tourism.     

旅游生态环境承载力计算方法研究

旅游环境承载力的评估是实现对生态旅游景区合理规划、有效管理,最终实现可持续发展必不可少的工具。本文运用生态学研究中生态足迹的概念和方法,通过分析生态旅游区的生态足迹的供给与需求,建立了基于生态足迹的环境承载力评估模型。     

Agricultural impacts on water quality and implications for virtual water trading decisions

Research on the flow of virtual water associated with agricultural crop production and trade has focussed almost entirely on water quantity. It is pertinent to consider and quantify the opportunity costs in terms of reduced water quality associated with crop production. This paper investigates the impacts of water quality on virtual water trading by creating a proxy for water quality impacts by calculating the amount of water required to dilute nonpoint-source agrochemical inputs to relevant water quality guideline values. The quantity of water required for dilution of five agrochemicals (two nutrients; nitrogen and phosphorus and three insecticides; azinphos-methyl, chlorpyrifos and endosulfan) was estimated for five crops in South Africa (maize, wheat, sugar cane, citrus and cotton) and compared to consumption of irrigation water (blue water) and rainfall (green water) for the same crops. Results indicate that the volume of water required for dilution is similar to the total sum of green and blue water required for crop production, but significantly greater than blue water use (irrigation use). For all crops phosphorus losses require greater amounts of water for dilution than for nitrogen, while pesticides result in the greatest water quality use. Estimates of water quality use are based on assumptions for a number of input variables (i.e. fertilizer application rates, percentage loss of agrochemicals from cropped areas). A Monte Carlo analysis (5000 iterations) was run to randomly select input variables from within defined ranges. Water quality use was calculated and expressed as a factor of blue water use. For all crops the average factor indicated that the volume of water required for dilution of all agrochemicals was greater than that required for irrigation. The results of this study clearly indicate that the impacts of agriculture on water quality need to be considered in virtual water trading scenarios. The incorporation of a method to predict impacts on water quality provides a comparative tool which generates a more holistic frame of reference for decision making with regard to impacts on the water resource and virtual water trading.     

A consumption-based approach to environmental Kuznets curves using the ecological footprint indicator

Recent research suggests that consumption-based measures offer an insightful perspective on the debate on the relationship between economic growth and the environment. In this article we deepen the consumption-based line of inquiry by investigating the empirical evidence in support of the environmental Kuznets hypothesis using 2001 ecological footprint data for 141 countries. We perform Ordinary Least Squares and Weighted Least Squares analysis on linear, quadratic and cubic functions, in standard and logarithmic specifications, as candidate models to represent the relationship between per capita income and environmental pressure. We replicate the cross country analysis also by estimating the regression function directly, through a nonparametric regression. In our analyses, with and without weighing data by population, the results do not show evidence of de-linking.     

虚拟水及其在缓解区域水资源短缺中的应用研究

虚拟水是指生产商品和服务所需要的水资源数量。虚拟水战略是指贫水国家或地区通过贸易的方式从富水国家或地区购买水密集型农产品(粮食)来获得本地区水和粮食的安全。本文在综述前人对虚拟水研究的基础上,计算了2002年甘肃省及不同地区主要农产品虚拟水含量,并对甘肃省加强虚拟水贸易的战略进行了探讨。     

The external water footprint of the Netherlands: Geographically-explicit quantification and impact assessment

This study quantifies the external water footprint of the Netherlands by partner country and import product and assesses the impact of this footprint by contrasting the geographically-explicit water footprint with water scarcity in the different parts of the world. The total water footprint of the Netherlands is estimated to be about 2300 m³/year/cap, of which 67% relates to the consumption of agricultural goods, 31% to the consumption of industrial goods, and 2% to domestic water use. The Dutch water footprint related to the consumption of agricultural goods, is composed as follows: 46% related to livestock products; 17% oil crops and oil from oil crops; 12% coffee, tea, cocoa and tobacco; 8% cereals and beer; 6% cotton products; 5% fruits; and 6% other agricultural products. About 11% of the water footprint of the Netherlands is internal and 89% is external. Only 44% of virtual-water import relates to products consumed in the Netherlands, thus constituting the external water footprint. For agricultural products this is 40% and for industrial products this is 60%. The remaining 56% of the virtual-water import to the Netherlands is re-exported. The impact of the external water footprint of Dutch consumers is highest in countries that experience serious water scarcity. Based on indicators for water scarcity the following eight countries have been identified as most seriously affected: China; India; Spain; Turkey; Pakistan; Sudan; South Africa; and Mexico. This study shows that Dutch consumption implies the use of water resources throughout the world, with significant impacts in water-scarce regions.     

Are virtual water “flows” in Spanish grain trade consistent with relative water scarcity?

Virtual water adds a new dimension to international trade, and brings along a new perspective about water scarcity and water resource management. Most virtual water literature has focused on quantifying virtual water “flows” and on its application to ensure water and food security. Nevertheless, the analysis of the potential gains from international trade, at least from a water resources perspective, needs to take into account both spatial and temporal variations of blue (groundwater and stream flow) and green (soil moisture) water, as well as the socioeconomic and policy conditions. This paper evaluates whether Spanish international trade with grains is consistent with relative water scarcity. For this purpose, the study estimates the volume and economic value of virtual water “flow” through international grain trade for the period 1997-2005, which includes 3 years with different rainfall levels. The calculations show that Spain is a net virtual water “importer” through international grain trade. The volume of net virtual water “imports” amounts to 3420, 4383 and 8415 million m³ in wet (1997), medium (1999) and dry (2005) years, respectively. Valuing blue water at its shadow price or scarcity value, blue water “exports” oscillate between 0.7 and 34.2 million Euros for a wet and dry year, respectively. Overall, grain trade is apparently consistent with relative water scarcity as net imports increase in dry years. However, the evolution of grain exports, expressed as a variation in quantity and volume, does not match the variations in resource scarcity. A disaggregated crop analysis reveals that there are other factors, such as quality, product specialization or the demand for a standardized product, which also influence trade decisions and are not included in the notion of virtual water. These facts, among others, can therefore create potential distortions in the application of virtual water to the analysis of specific trade patterns. Nevertheless, from a water resources perspective, virtual water can bring important insights across countries for improving water and land management globally, fostering adaptation strategies to climate change and to transboundary resource management.     

县域农业流域循环经济发展水平评价--以金华江中游为例

建立区域生态可持续发展循环经济体系的前提是客观正确的评价。本研究以生态足迹模型理论为基础,以区域小流域层次作为研究目标对象,对农业流域生态经济系统评价方法展开研究,同时为区域生态及社会经济的可持续发展政策制定提供理论支持。研究以金华江中游为例,分析比对该流域内各类型土地间的生态足迹供需情况,进而解释和评价该流域循环经济发展水平。结果显示金华江中游流域的生态环境是非常脆弱的,无法支撑此流域经济的进一步发展;该流域资源开发不尽合理,废弃物处理效率低,循环经济发展方向有进一步恶化的风险,总体上处于不可持续状态。在对流域循环经济发展水平进行分析后,本研究提出了以改变生产和生活方式为切入点,以提高资源利用率为导向,通过提高单位面积的自然生产力和控制区域人口来减低生态赤字的政策建议。     

Application of ecological footprint in ecological industrial systems：a study case of maize-MSG production systems

To improve the comparability of the research results of ecological industry, the ecological footprint is appliedto analyze the resource utilization and environmental pollution in various subsystems, taking maize-MSG as a case.Results show that the production process from maize to MSG is a extended process of ecological footprint, and that theecological footprint of the maize production is the biggest; the extension of ecological footprint is followed by the increaseof footprint profit, which means that the extension of production chain is an important method to improve the resourcesprofit; the systems have a big proportion of the indirect energy ecological footprint; the air and water pollution in MSGsubsystem is the most serious. At last, it can be identified that ecological footprint is a good method to measure resourceutilization and environmental pollution in various subsystems of an integrated ecological industry.