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1.
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   

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.
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   

4.
Biomass trade results in a growing spatial disconnect between environmental impacts due to biomass production and the places where biomass is being consumed. The pressure on ecosystems resulting from the production of traded biomass, however, is highly variable between regions and products. We use the concept of embodied human appropriation of net primary production (HANPP) to map the spatial disconnect between net-producing and net-consuming regions. Embodied HANPP comprises total biomass withdrawals and land use induced changes in productivity resulting from the provision of biomass products. International net transfers of embodied HANPP are of global significance, amounting to 1.7 PgC/year. Sparsely populated regions are mainly net producers, densely populated regions net consumers, independent of development status. Biomass consumption and trade are expected to surge over the next decades, suggesting a need to sustainably manage supply and demand of products of ecosystems on a global level.  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.
Since the 1980s Chinese economic reform has greatly accelerated its economic growth while in contrast China's environment is increasingly degraded. The Chinese government has recognized that environmental protection and sustainable economic development can promote mutual and sustainable co-development of the economy and the environment as a basic national principle. This paper examines the interactions between economic development and environmental change in China that were compared and analyzed for the years 1996 and 2000. Net primary production (NPP) was selected as a proxy evaluator of ecosystems and gross domestic product (GDP) was chosen as a proxy evaluator of economic development. An NPP change map was produced with Advanced Very High Resolution Radiometer (AVHRR) summed annual NPP imagery products. The Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) nighttime imagery was used to produce a Chinese GDP change map. An integrated map was produced to exhibit the combined changes of NPP and GDP. This map showed that in the regions with increased GDP, NPP decreased but the regions with no GDP change were smaller in area for NPP increase while larger in area for NPP decrease. The changing pattern of NPP varied with the developing level of GDP at province level. A province's development of GDP is controlled by its accessibility to natural resources. Interactions between NPP and GDP are greatly affected by factors of spatial location aside from human factors and natural systems' characteristics.  相似文献   

7.
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   

8.
This paper analyses the role of global land management alternatives in determining potential greenhouse gas mitigation by land-based activities in agriculture and forestry. Land-based activities are responsible for over a third of global greenhouse gas emissions, yet the economics of land-use decisions have not been explicitly modeled in global mitigation studies. In this paper, we develop a new, general equilibrium framework which effectively captures the opportunity costs of land-use decisions in agriculture and forestry, thereby allowing us to analyse competition for heterogeneous land types across and within sectors, as well as input substitution between land and other factors of production. When land-using sectors are confronted with a tax on greenhouse gas emissions, we find significant changes in the global pattern of comparative advantage across sectors, regions, and land types. Globally, we find that forest carbon sequestration is the dominant strategy for GHG emissions mitigation, while agricultural-related mitigation comes predominantly from reduced methane emissions in the ruminant livestock sector, followed by fertilizer and methane emissions from paddy rice. Regionally, agricultural mitigation is a larger share of total land-use emissions abatement in the USA and China, compared to the rest of the world, and, within agriculture, disproportionately from reductions in fertilizer-related emissions. The results also show how analyses that only consider regional mitigation, may bias mitigation potential by ignoring global market interactions. For example, USA-specific analyses likely over-estimate the potential for abatement in agriculture. Finally, we note that this general equilibrium framework provides the research community with a practical methodology for explicit modeling of global land competition and land-based mitigation in comprehensive assessments of greenhouse gas mitigation options.  相似文献   

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