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571.
Stefan Norra 《Environmental science and pollution research international》2009,16(5):539-545
Background, aim, and scope In 1875, the geoscientist Walter Suess introduced several spheres, such as the lithosphere and the atmosphere to promote a
comprehensive understanding of the system earth. Since then, this idea became the dominating concept for the understanding
of the distribution of chemical elements in the system earth. Meanwhile, due to the importance of human beings on global element
fluxes, the term anthroposphere was introduced. Nevertheless, in face of the ongoing urbanization of the earth, this concept
is not any more adequate enough to develop a comprehensive understanding of global element fluxes in and between solid, liquid,
and gaseous phases. This article discusses a new concept integrating urbanization into the geoscientific concept of spheres.
Main features No geological exogenic force has altered the earth’s surface during the last centuries in such an extent as human activity.
Humans have altered the morphology and element balances of the earth by establishing agrosystems first and urban systems later.
Currently, urban systems happen to become the main regulators for fluxes of many elements on a global scale due to ongoing
industrial and economic development and a growing number of inhabitants. Additionally, urban systems are constantly expanding
and cover more and more former natural and agricultural areas. For nature, urban systems are new phenomena, which never existed
in previous geological eras. The process of the globe’s urbanization concurrently is active with the global climate change.
In fact, urban systems are a major emitter for climate active gases. Thus, beside the global changes in economy and society,
urbanization is an important factor within the global change of nature as is already accepted for climate, ecosystems, and
biodiversity.
Results Due to the fact that urbanization has become a global process shaping the earth and that the urban systems are globally cross-linked
among each other, a new geoscientific sphere has to be introduced: the astysphere. This sphere comprises the parts of the
earth influenced by urban systems. Accepting urbanization as global ongoing process forming the astysphere comprehensively
copes with the growing importance of urbanization on the creation of present geologic formations.
Discussion Anthropogenic activities occur mainly in rural and urban environments. For long lasting periods of human history, human activities
mainly were focused on hunting and agriculture, but since industrialization, urbanized areas became increasingly important
for the material and energy fluxes of earth. Thus, it seems appropriate to classify the anthroposphere into an agriculturally
and an urban-dominated sphere, which are the agrosphere (Krishna 2003) and the astysphere (introduced by Norra 2007).
Conclusions We have to realize that urban systems are deposits, consumers, and transformers of resources interacting among each other
and forming a network around the globe. Since the future of human mankind depends on the sustainable use of available resources,
only a global and holistic view of the cross-linked urban systems forming together the astysphere provide the necessary geoscientific
background understanding for global urban material and energy fluxes. If we want to ensure worth-living conditions for future
generations of mankind, we have to develop global models of the future needs for resources by the global metasystem of urban
systems, called astysphere.
Perspectives The final vision for geoscientific research on the astysphere must be to design models describing the global process of urbanization
of the earth and the development of the astysphere with respect to fluxes of materials, elements, and energy as well as with
respect to the forming of the earth’s face. Besides that, just from the viewpoint of fundamental research, the geoscientific
concept of spheres has to be complemented by the astysphere if this concept shall fully represent the system earth.
相似文献
Stefan NorraEmail: |
572.
A. N. Polezhaev 《Russian Journal of Ecology》2009,40(3):166-171
The cartographic method, in combination with computer technologies and special software, was used to develop a series of projects of geographic information systems (GISs), including regional GISs (RGISs) for three administrative regions (Magadan oblast, Chukchi Autonomous Area, and Koryak Autonomous Area) and the territorial GIS Vegetation of the Northern Russian Far East. 相似文献
573.
Paolo C. Campo Guillermo A. Mendoza Philippe Guizol Teodoro R. Villanueva Franois Bousquet 《Journal of environmental management》2009,90(11):3607-3615
This paper describes the experiences and lessons learned in applying a multi-agent systems (MAS) model to study the dynamics and complex interactions among stakeholders in the management of community-based forests. The MAS model is developed using the companion modelling (ComMod) approach, which allows for a collaborative development of the model between the stakeholders and researchers. This approach involves the development and application of role-playing games (RPGs) and computer simulation as learning tools and to validate the model. Inferences are drawn from the learning and negotiation processes that the stakeholders and researchers underwent in the collaborative development of the MAS model. These processes ultimately led to the development of a collaborative resource management plan. The approach and the MAS model were applied to a case study involving a community-based forest managed by three villages in the island of Palawan, Philippines. 相似文献
574.
Lloyd-Smith M 《Journal of environmental management》2009,90(4):1628-1635
In the environmental conflict that surrounds the sighting of hazardous waste facilities there is usually a volatile mix of disparities in power, expertise and information access as well as differing views on risk, which are all played out amidst commercial arrangements and environmental justice concerns. In recent times, the volatility of this mix has been further compounded by the growing climate of public concern and distrust surrounding scientific developments and technology. While there is no 'quick fix' to the complex conflict that this entails, community information systems (CISs) based on participatory models can help address the outstanding issues of capacity, information access, power inequities and environmental justice. CISs are an effective response to the five crucial elements of a toxic dispute, that is, the dialogue, capacity building, information access, evaluation of hazards and risk, and expertise. This paper will review the role of community accessible information systems in the dispute in Botany over the management and destruction of Orica Australia's stockpile of the persistent organic pollutant, hexachlorobenzene (HCB). It will focus on the role of CIS in responding to the challenges for expert information delivery, and in addressing the disparity of informational power within the toxic dispute. 相似文献
575.
Andreas C. Bryhn Antonio Jiménez Alfonso Mateos Sixto Ríos-Insua 《Journal of environmental management》2009
A multi-attribute analysis by means of the general multi-attribute analysis (GMAA) decision support system was performed in order to rank different strategies for good water quality with respect to trophic state, and good conditions for waterfowl, in the lagoon Ringkøbing Fjord, Denmark. The remedial strategies included nutrient abatement and the construction of facilities to increase the water exchange between the lagoon and the sea. The analysis showed that it is essential to keep the mean annual salinity level constant, since a drastic change in salinity may cause massive destruction of the macrophyte belt with large effects on the water quality and waterfowl abundance. It may be cost-effective to build and maintain a saltwater pumping station or a second sluice to increase the seawater inflow. Further nutrient abatement may not be cost-effective, at least not on time-scales shorter than 20 years, but the utility from nutrient abatement increases if a second sluice is built additionally. However, all of the remedial strategies, except decreasing the salinity, were projected to cause rather small changes in the effect variables compared to the no action alternative. 相似文献
576.
Basic scenarios of sustainable development for the world community and approaches to the problem of ensuring food security
are discussed. The conservation of agricultural resources is the key element of food security. The structure and main objectives
of agroecology are characterized in brief. 相似文献
577.
578.
Many species of territorial animals are more aggressive toward strangers than neighbors, a pattern of aggression referred
to as the ’dear-enemy phenomenon.’ In many cases, the mechanism by which neighbors are discriminated from strangers and the
function of neighbor-stranger discrimination remain controversial. We investigated the spatial patterns of inter-colony aggression
within and between two Pheidole species of seed-harvesting ants in the Mojave Desert of California by quantifying aggression between colonies in standardized
staged encounters. We also tested whether the level of fighting between workers of two colonies is affected by previous exposure
to each other. We show that neighbors (i.e., colonies less that 2.6 m away) of either species are treated less aggressively
than more distant colonies and that habituation may be a mechanism by which this discrimination is achieved. The variation
in aggression among spatially distant colonies also suggests that additional genetic or environmental factors are involved
in recognition. The function of the dear-enemy phenomenon in these ant species may be related to the greater risk to the resources
of a colony presented by strange workers than workers from a neighboring colony.
Received: 18 November 1999 / Received in revised form: 3 April 2000 / Accepted: 3 May 2000 相似文献
579.
Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of Haihe River, Tianjin, China 总被引:7,自引:0,他引:7
JIANG Bin ZHENG Hai-long HUANG Guo-qiang DING Hui LI Xin-gang SUO Hong-tu LI Rui 《环境科学学报(英文版)》2007,19(3):306-311
In this study sediment samples were collected from 13 sites of Haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons (PAHs) listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin. 相似文献
580.
为加强环境自动监测系统的建设,提供了一个支持多种类型现场信息宽接入的信息采集、支持有线和无线信息传输的开放式在线数据采集传输装置.装置用标准化的工控机作为控制核心,具备模拟信号、LonWorks信号、视频信号、RS-485信号输入接口,网络通信和GPRS远程通信方式,采用Windows操作系统和数据库技术,应用方便灵活,有助于提供有效、客观的现场环境信息,实现环境自动监测与管理. 相似文献