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1.
Humanity's role in shaping patterns and processes in the terrestrial biosphere is large and growing. Most of the earth's fertile land is used more or less intensively by humans for resource extraction, production, transport, consumption and waste deposition or as living space. Biomass production on cropland, grazing areas and in managed forests dominates area requirements, but other processes such as soil degradation, human-induced fires and expansion of settlements and infrastructure play an increasingly important role as well. The growing human domination of terrestrial ecosystems contributes to biodiversity loss as well as to a reduced capability of ecosystems to deliver vital services such as buffering capacity, soil conservation or self-regulation. This special section is devoted to the presentation of recent research into the patterns, determinants and implications of the human appropriation of net primary production (HANPP), an integrated socio-ecological indicator of land use intensity. By measuring the combined effect of land conversion and biomass harvest on the availability of trophic energy (biomass) in ecosystems, HANPP explicitly links natural with socioeconomic processes and allows for integrated analyses of land systems. This introductory article explains the rationale that links current HANPP research to Ecological Economics and discusses issues of definition and methods shared by all articles included in the special section. Finally, it gives an overview of the individual papers, provides some general conclusions and presents an outlook for future research: a better understanding of long-term trajectories of HANPP, of the significance of trade patterns as well as of the future role of bioenergy are highlighted as important issues to be addressed in the coming years.  相似文献   

2.
The human appropriation of net primary production (HANPP) is an indicator of the human domination of ecosystems that measures to which extent human activities alter the amount of biomass available each year in ecosystems. This paper analyses the development of aboveground HANPP (aHANPP) in Spain for the period from 1955 to 2003. During this period, Spain's agriculture underwent a transition from a largely pre-industrial to a highly intensified production system. Changes in land use patterns include a reduction of cropland area and an expansion of forest area. Results show that aHANPP declined from 67% of potential aNPP in 1955 to 61% in 2003. Biomass harvest strongly increased from 68 million tons dry matter biomass per year (Mt/yr) to 106 Mt/yr, with nearly all of this increase occurring on cropland. Productivity losses due to human-induced land conversions dropped significantly from 112 Mt/yr to 63 Mt/yr, mainly as a result of the surge in cropland productivity and the increase in forest area. Despite its decrease during the last decades, aHANPP in Spain is still at a remarkably high level in comparison with the global average or other industrialized countries.  相似文献   

3.
The “human appropriation of net primary production” (HANPP) has been suggested as a comprehensive indicator to measure impacts of human land use on ecosystems. It accounts for (a) human-induced changes in biological productivity and (b) biomass harvest. This study presents an analysis of aboveground HANPP in the Philippines between 1910 and 2003, a period characterized by massive deforestation and increases in land use intensity and biomass extraction. Results show a steep increase of aboveground HANPP from just below 35% of potential productivity in 1910 to slightly above 60% in 1970 and constant values since then. Large-scale changes in land cover and agricultural practices were the main direct determinants of this trajectory in HANPP. Remarkably, HANPP grew at much slower pace than population did: While the amount of NPP appropriated by humans doubled throughout the period, population increased by a factor ten. Increasing efficiency in terms of biomass extraction per unit of area, relying on ever-increasing inputs, and changes in the nation's physical biomass trade balance were of major importance for this difference in growth rates. In the coming decades, the Philippines will have to face the challenge to meet increases in biomass demand without putting even higher strains on the ecosystems.  相似文献   

4.
Land degradation, the temporary or permanent reduction of land's productive capacity resulting from poor land management, has gained considerable attention as an environmental and development issue of global importance, in particular in the Earth's drylands. This study presents a global estimate of net primary production (NPP) losses caused by human-induced dryland degradation. Due to the large uncertainties related to international databases on dryland degradation, we compiled a world map of the extent and degree of desertification based on existing regional and global maps. Two distinct approaches were followed in order to estimate NPP losses due to degradation on drylands: in the first approach, we combined these maps with model results on global potential NPP, determined with the LPJ-DGVM, with a set of factors on NPP losses per degradation degree, derived from the literature. In a second approach, we made use of spatially explicit information on potential and current NPP of agricultural areas obtained from a global HANPP assessment [Haberl, H., Erb, K.-H., Krausmann, F., Gaube, V., Bondeau, A., Plutzar, C., Gingrich, S., Lucht, W. and Fischer-Kowalski, M., 2007. Quantifying and mapping the human appropriation of net primary production in earth's terrestrial ecosystems. Proceedings of the National Academy of Sciences of the United States of America, 104: 12942-12947.]. We used the difference between potential and current NPP on croplands situated in drylands in order to quantify the effect of dryland degradation on NPP. NPP losses were found to range between 799 and 1936 Tg C/yr in the first approach, and to amount to 965 Tg C/yr in the second approach. Overall, approximately 2% of the global terrestrial NPP are lost each year due to dryland degradation, or between 4% and 10% of the potential NPP in drylands. NPP losses amount to 20-40% of the potential NPP on degraded agricultural areas in the global average and above 55% in some world regions. The results reveal that the contributions of dryland degradation to the total HANPP in drylands is of similar dimension than the overall annual socioeconomic biomass harvest. Accordingly, strategies aimed at reducing dryland degradation could present promising options to sustain future population numbers without putting further pressures on dryland ecosystems.  相似文献   

5.
This paper presents an empirical analysis of the human appropriation of aboveground net primary production (aHANPP) in Hungary in the years 1961-2005. In this period aboveground HANPP dropped from 67% to 49% of the potential vegetation's NPP. The trajectory was not smooth, but aboveground HANPP fluctuated with changes in factors affecting agricultural production conditions. Both aboveground net primary production (aNPP) of the prevailing vegetation and harvested aNPP increased during the socialist regime, dropped when the system collapsed and has shown considerable fluctuations since. We discuss the development of aboveground HANPP and the Hungarian land use system in the context of socioeconomic changes during three distinct phases: (1) industrialisation of agriculture (1961-1989), (2) regime collapse (1989-1993) and (3) restructuring of a new economy (1993-2005). Within these periods, different driving factors influenced aboveground HANPP and its constituents. In the phase of industrialisation, mechanisation and agrochemical inputs reduced aHANPP while harvested amounts of biomass increased progressively. In the second phase, political and economic circumstances devastated production conditions resulting in a decline of productivity of actual vegetation and a temporary rise in aboveground HANPP. During the last twelve years, industrialisation patterns of agricultural production recovered. The restructuring of inefficient agricultural production systems raised harvest at moderate levels of agricultural inputs, while climatic conditions intimidated high yield and harvest security. The paper discusses the effect of different economic and political regimes and of major socioeconomic restructuring on the development of the land use system, biomass production and aboveground HANPP.  相似文献   

6.
We test—at the global scale—the hypothesis that human beings tend to build settlements in areas of high biological productivity, and protect (as parks) areas of low productivity. Furthermore, we propose an alternative measure of the extent and effectiveness of the global protected areas network based on potential net primary production (NPP0). The average NPP0 in urban areas and parks is calculated and compared to the average NPP0 of the geopolitical regions and biomes containing these areas. Additionally, human appropriation of net primary production (HANPP) in parks is used as an indicator of the effectiveness of these protected areas. We find that in almost all regions of the world, humans have chosen to settle in the most productive areas. At the global scale, urban areas have considerably higher NPP0 (592 g Cm− 2 yr− 1) than the global average (494 g Cm− 2 yr− 1), while parks have roughly average NPP0 (490 g Cm− 2 yr− 1). Parks with an IUCN category of I-VI account for 9.5% of the planet's terrestrial NPP0, compared to 9.6% of its terrestrial area. Although protected area and protected NPP0 are nearly equal, this equivalence is diminished by HANPP within parks. Globally, the average HANPP in all protected areas is 14% of their NPP0, and HANPP within parks increases as the park management category becomes less restrictive. Moreover, we find a positive correlation between HANPP in parks and the extent of urbanization in the surrounding region and biome. Area-based targets for conservation provide no information on either the quality of the areas we choose to protect, or the effectiveness of that protection. We conclude that NPP0 and HANPP may provide an additional, useful tool for assessing the extent and effectiveness of the global protected areas network.  相似文献   

7.
运用投入产出模型,首先测算了2002年、2007年及2012年陕西省工业品隐含碳排放量情况。结果发现,3个年份陕西省隐含碳排放量不断增加且呈现出较高的行业集中度,排名前5位的部门由高到低分别为石油化工业、煤石油开采业、金属制品业、非金属制品业及计算机设备制造业。随后,分析了2002年、2007年及2012年陕西省工业品隐含碳排放失衡度。结果表明,在国际贸易方面,上述3个年份陕西省均为隐含碳排放净出口方,说明陕西省为其它国家承担了能源环境负荷;在国内贸易方面,陕西省2002年和2007年为隐含碳排放的净调入方,而2012年变为净调出方,这主要是因为陕西省调出产品增幅较大造成的;在总贸易方面,陕西省隐含碳流动方向与国内贸易相同,这是由于陕西内贸规模远远大于其外贸规模。目前来看,较大的隐含碳流出虽然有利于陕西省经济增长,但所付出的环境代价却不容忽视。因此,陕西省需提高生产技术水平、实现产业结构优化升级与贸易结构低碳化协调发展。  相似文献   

8.
Human use of biomass has become a major component of the global biogeochemical cycles of carbon and nitrogen. The use of land for biomass production (e.g. cropland) is among the most important pressures on biodiversity. At the same time, biomass is indispensable for humans as food, animal feed, raw material and energy source. In order to support research into these complex issues, we here present a comprehensive assessment of global socioeconomic biomass harvest, use and trade for the year 2000. We developed country-level livestock balances and a consistent set of factors to estimate flows of used biomass not covered by international statistics (e.g. grazed biomass, crop residues) and indirect flows (i.e. biomass destroyed during harvest but not used). We found that current global terrestrial biomass appropriation amounted to 18.7 billion tonnes dry matter per year (Pg/yr) or 16% of global terrestrial NPP of which 6.6 Pg/yr were indirect flows. Only 12% of the economically used plant biomass (12.1 Pg/yr) directly served as human food, while 58% were used as feed for livestock, 20% as raw material and 10% as fuelwood. There are considerable regional variations in biomass supply and use. Distinguishing 11 world regions, we found that extraction of used biomass ranged from 0.3 to 2.8 t/ha/yr, per-capita values varied between 1.2 and 11.7 t/cap/yr (dry matter). Aggregate global biomass trade amounted to 7.5% of all extracted biomass. An analysis of these regional patterns revealed that the level of biomass use per capita is determined by historically evolved patterns of land use and population density rather than by affluence or economic development status. Regions with low population density have the highest level of per-capita biomass use, high-density regions the lowest. Livestock, consuming 30-75% of all harvested biomass, is another important factor explaining regional variations in biomass use. Global biomass demand is expected to grow during the next decades; the article discusses some options and possible limitations related to such a scenario.  相似文献   

9.
高静  刘友金 《当代财经》2012,(5):94-105
中美贸易的巨额逆差带来的不仅仅是贸易问题,还包括一系列的环境问题。利用环境投入产出模型测算1997年-2009年中美贸易中所隐含的CO2排放量,得出如下结论:中美贸易中中国大部分行业污染贸易条件均大于1,且呈不断恶化趋势;出口规模越大、贸易竞争力越强的产业单位出口的CO2排放强度越小,中国出口美国的产品与污染品并无必然联系;美国对华FDI转移并未引起美国污染产业向中国转移,而全球FDI向华转移使得"污染天堂"理论在华成立;中国出口CO2排放速度低于其出口速度,单位出口的CO2排放强度呈下降趋势;改变中国污染顺差国的地位,中国需加强对美国污染品的进口,积极改变粗放型的生产方式,加快对价值链高端清洁产品的生产。  相似文献   

10.
This paper presents an empirical analysis of the United Kingdom's society's long-term intervention into the energy flows of domestic terrestrial ecosystems through the human appropriation of aboveground net primary production (aHANPP) covering the period 1800-2000. The depicted aHANPP trajectory and the historical development of its components are discussed in view of a continuously increasing population and the transition process from an agrarian to an industrial socioecological regime. During the 19th century, aHANPP shows a steady decline from its level of 71% in 1800. While even higher levels were reached during the mid 20th century, the trend during the last forty years of the period under investigation again shows a reduction of aHANPP, which lies at 68% in the year 2000. The high values of aHANPP in the United Kingdom are primarily attributable to the limited amount of forest in comparison to large agricultural areas. At the beginning of the studied period, the relative stabilisation or even decrease in aHANPP in comparison to population development was made possible through the area expansion of and productivity increases on cropland and permanent pastures. Later this was made possible through the outsourcing of biomass harvest, by satisfying local nutritional demands by means of overseas imports, and as from the mid 20th century through huge amounts of fossil fuel based inputs into agriculture (e.g. increased amounts of fertilizers and motorized traction) which allowed increases in biomass harvest to be decoupled from HANPP.  相似文献   

11.
Effective policies to slow the rate of anthropogenic biodiversity loss should reduce socioeconomic pressures on biodiversity, either directly or by modifying their underlying socioeconomic driving forces. The design of such policies is currently hampered by the limited understanding of socioeconomic drivers of and pressures on biodiversity as well as by lacking data, indicators and models. In order to improve understanding of these issues we here propose a conceptual model of socioeconomic biodiversity drivers and pressures. The model is based on the drivers-pressures-impacts-states-responses (DPSIR) scheme and on the socioeconomic metabolism approach. The aim of the model is to guide research aimed at improving our understanding of socioeconomic biodiversity pressures and drivers and to serve as a basis for the development of formal, quantitative models in that field. Based on three European long-term socio-ecological research (LTSER) platforms, we analyze the model's applicability and suitability as well as data availability and research needs. These platforms are the Danube Delta Wetland System in Romania, the Doñana in Spain and the Eisenwurzen in Austria. An empirical analysis of the relationship between the human appropriation of net primary production (HANPP) and breeding bird richness in the Eisenwurzen demonstrates the ability of HANPP to provide a link between socioeconomic pressures/drivers and biodiversity. The analysis of the case studies underlines the potential utility of the conceptual model to guide future research into socioeconomic biodiversity drivers and pressures. However, considerable investments in monitoring and reconstruction of past trajectories as well as in model development will be required before mathematical (computer) models of the interrelation processes between society and ecosystems can be successfully deployed.  相似文献   

12.
董桂才 《技术经济》2007,26(4):85-89
相对于水价和用水技术能够提高水资源在当地的配置效率,虚拟水贸易则可以提高水资源在全球范围内的配置效率。虚拟水从水资源生产率较高的国家流向水资源较低的国家意味着在全球层次上水资源的节约。因此,国家之间、洲际之间虚拟水贸易被看作提高全球水资源利用效率和缺水国家获得水安全的一个有力工具。  相似文献   

13.
Recent analyses of the evolution and structure of trade in virtual water revealed that the number of trade connections and volume of virtual water trade have more than doubled over the past two decades, and that developed countries increasingly import water embodied in goods from the rest of the world to alleviate pressure on domestic water resources. At the same time, as demand continues to increase and climate change threatens to alter hydrological cycles, water scarcity is a growing problem. Does research into virtual water trade need to consider water scarcity and differentiate flows out of water-scarce regions from flows out of water-abundant regions? Previous studies sum and compare virtual water volumes originating in countries experiencing vastly different degrees of water scarcity. We therefore incorporate water scarcity into an assessment of global virtual water flows. We use input–output analysis to include indirect virtual water flows. We find that the structure of global virtual water networks changes significantly after adjusting for water scarcity.  相似文献   

14.
In this paper we construct bilateral emission trade balances (ETB) for The Netherlands with 17 regions and compare results for 1996 and 2007 for three different greenhouse gasses. We establish a cross-sectional analysis of bilateral ETBs into a volume of trade, composition and technology effect. In order to analyze the driving forces of changes over time we perform a structural decomposition analysis of embodied import and export emissions. The main findings are that the embodied import emissions have increased by 37% whereas export emissions increased by only 3%, which is primarily driven by CO2. The 2007 bilateral balances are positive with OECD countries but negative with economies such as Russia, Africa and China. The analyses demonstrate that the worsening of the ETB is to a large extent caused by the changing composition of trade: the Dutch economy increasingly exports clean products and imports dirty products.  相似文献   

15.
Climate change and its consequences present one of the most important threats to biodiversity and the functions of ecosystems. The stress on biodiversity is far beyond the levels imposed by the natural global climatic changes occurring in the recent evolutionary past. It includes temperature increases, shifts of climate zones, melting of snow and ice, sea level rise, droughts, floods, and other extreme weather events. Natural systems are vulnerable to such changes due to their limited adaptive capacity. Based on an analysis using the DPSIR framework, this paper discusses some of the important socio-economic driving forces of climate change, with a focus on energy use and transportation. The paper also analyses observed and potential changes of climate and the pressures they exert on biodiversity, the changes in biodiversity, the resulting impacts on ecosystem functions, and possible policy responses. The latter can be divided into mitigation and adaptation measures. Both strategies are needed, mitigation in order to stabilise the greenhouse gas concentrations in the atmosphere, and adaptation in order to adjust to changes that have already occurred or cannot be avoided. One mitigation option, increased biofuel production, which is also a response to oil depletion, would change land use patterns and increase human appropriation of net primary production of biomass, thereby threatening biodiversity. By considering the first order and second order impacts of climate change on biodiversity when developing policy measures, it will be possible to integrate ecosystem and biodiversity protection into decision-making processes.  相似文献   

16.
How do shifts in trade affect social protections for the poor? Although the fraction of the world's population considered the “extreme” poor has fallen by over one-half over the past quarter century, many of those lifted above the global poverty line remain vulnerable to shocks that could place them back into poverty. These are the groups that require social protection to stabilize their incomes. Among the shocks to which the absolute poor have been exposed are those created by trade liberalization, particularly of the agricultural sector. The resulting risks, uncertainties, and threats to social stability from this type of trade require that the poor be provided with some forms of adjustment assistance. We examine the effects of trade components on several dimensions of social protection in developing countries, including spending, coverage, and adequacy over the past two decades. We find that, contrary to previous studies, disaggregating trade may be a key to determining which international market variables drive expansion of social protection. Disaggregating trade balances in agricultural vs. manufactured goods reveals that net food and agricultural exporters provide better social protection than countries that report agricultural trade deficits. Meanwhile, countries with manufacturing trade surpluses tend to experience reduced social protection coverage. We reason that governments of net agricultural exporters face incentives to invest in social programs that extend eligibility to the rural poor. Manufacturing export-driven economies, on the other hand, are likely participants in global production chains that limit the capacity of the public sector to extend social protection.  相似文献   

17.
This paper investigates the trade‐off between distribution effect and production effect of monetary policy when there exist unobservable idiosyncratic liquidity shocks. In the absence of risk‐sharing arrangements such as a credit market, monetary policy serves to provide ex post insurance to smooth consumption. Specifically, issuing interest‐bearing bonds restores credit transactions on money through bond‐money exchanges. Such a policy has a positive distribution effect, but the resulting inflation hampers production efficiency. It is demonstrated that the trade‐off between distribution efficiency gain and production efficiency loss would result in net welfare enhancement if consumers are relative‐risk‐averse enough.  相似文献   

18.
This study develops a world spatial equilibrium softwood lumber model comprised of the major importing and exporting countries/regions to analyse the impacts of global trade reform on the world softwood lumber market. The results show that free trade leads to an increase in lumber trade, and Canadian producers and US consumers are the biggest beneficiaries. Trade liberalization improves the overall world welfare as world producer and consumer surpluses increase. The result highlights the importance of moving towards free trade in the global softwood lumber market.  相似文献   

19.
The Ecological Footprint as an indicator that accounts for human demand on global bioproductivity sets out to quantify the impacts associated with consumption in a given country, including the impacts associated with trade. The National Footprint Accounts (NFA) by Global Footprint Network (GFN) calculate trade-embodied Footprints by multiplying yield and embodied energy factors with mass volumes of traded goods in a “Product Land Use Matrix (PLUM)”. This article compares energy Footprints embodied in trade from and to the United Kingdom in 2002 as calculated by the NFA-PLUM with the results from a recently developed multi-region input-output model (MRIO) for the UK. Although totals for imports and exports are comparable, breaking down the results by economic sectors reveals large differences and hardly any correlation between the two methods. The omission of trade in services (especially transport services) and upstream impacts of energy goods (fossil fuels) and the use of inappropriate embodied energy factors in the NFA-PLUM method are identified as the main reasons for these differences.In the light of the results it seems that a comprehensive Footprint account of trade can better be achieved with an input-output based approach. I conclude that MRIO models - once fully developed - will be particularly suitable in the future to estimate the Ecological Footprints of imports and exports of nations with the possibility to track their origin via inter-industry linkages, international supply chains and multi-national trade flows.  相似文献   

20.
This paper offers a detailed review of recently described single- and multi-region input-output models used to assess environmental impacts of internationally traded goods and services. It is the second part of a two-part contribution. In Part 1 [Turner, K., Lenzen, M., Wiedmann, T. and Barrett, J. in press. Examining the Global Environmental Impact of Regional Consumption Activities — Part 1: A Technical Note on Combining Input-Output and Ecological Footprint Analysis; Ecological Economics.] we describe how to enumerate the resource and pollution content of inter-regional and inter-national trade flows with the aim to illustrate an ideal accounting and modelling framework for the estimation of Ecological Footprints.A large number of such environment-economic models have been described but only in the last few years models have emerged that use a more sophisticated multi-region, multi-sector input-output framework. This has been made possible through improvements in data availability and quality as well as computability. We identify six major models that employ multi-sector, multi-region input-output analysis in order to calculate environmental impacts embodied in international trade. Results from the reviewed studies demonstrate that it is important to explicitly consider the production recipe, land and energy use as well as emissions in a multi-region, multi-sector and multi-directional trade model with global coverage and detailed sector disaggregation. Only then reliable figures for indicators of impacts embodied in trade, such as the Ecological Footprint, can be derived.  相似文献   

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