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Models of natural and human dynamics in forest landscapes: Cross-site and cross-cultural synthesis 总被引：1，自引：0，他引：1
Miguel F. Acevedo J. Baird Callicott Donald Lyons Judith Rosales Magdiel Ablan Giorgio Tonella Emilio Vilanova 《Geoforum》2008,39(2):846-866
We synthesize the study of coupled natural and human systems across sites and cultures through a process of simplification and abstraction based on multiple dimensions of human-nature connectedness: satisfaction of basic needs, psycho-cultural connectedness and regulation of use of natural resources. We thus provide both a place-based and general understanding of value-driven anthropogenic environmental change and response. Two questions guide this research: what are the crucial stakeholder values that drive land use decisions and thus land cover change? And how can knowledge of these values be used to make decisions and policies that sustain both the human and natural systems in a place? To explore these questions we build simulation models of four study sites, two in the State of Texas, United States, and two in Venezuela. All include protected areas, though they differ in the specifics of vegetation and land use. In the Texas sites, relatively affluent individuals are legally converting forests to residential, commercial, and industrial uses, while in Venezuela landless settlers are extra-legally converting forests for purposes of subsistence agriculture. Contemporary modeling techniques now facilitate simulations of stakeholder and ecosystem dynamics revealing emergent patterns. Such coupled human and natural systems are currently recognized as a form of biocomplexity. Our modeling framework is flexible enough to allow adaptation to each of the study sites, capturing the essential features of the respective natural and anthropogenic land use changes and stakeholder reactions. The interactions between human stakeholders are simulated using multi-agent models that act on forest landscape models, and receive feedback of the effects of these actions on ecological habitats and hydrological response. The multi-agent models employ a formal logic-based method for the Venezuelan sites and a decision analysis approach using multi-attribute utility functions for the Texas sites, differing more in style and emphasis than in substance. Our natural-systems models are generic and can be tailored according to site-specific conditions. Similar models of tree growth and patch transitions are used for all the study sites and the differing responses to environmental variables are specified for each local species and terrain conditions. 相似文献
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H. Hellmann 《洁净——土壤、空气、水》1996,24(5):218-225
IR Spectroscopy and Further Analyses of New Fabric Rinse Agents Distearyldimethylammoniumchloride (DSDMAC) that dominated the fabric softener market in Germany in the past is now substituted by three new types of ester-based agents, i.e. imidazoline ester, ester quats, and diester quats what poses new challenges to surface water analytics. The IR spectra and the chromatographic behaviour of these three agents are more or less similar to those of naturally occuring fatty esters. The paper reports about the use of IR spectroscopy, its benefit in the sense of fingerprinting principle, the identification of substances by functional groups, and the analytical tracing of transformation products. The latter relates to the formation of salts with anions that are easily detectable, the clean up, and the final spectroscopic determination. While in 1994 DSDMAC was still determinable in concentrations of 10…20 mg/kg in suspended solids from the Middle Rhine River, the concentration of the substitutes was below the detection limit of 2 mg/kg and 1…2 μg/L in 1995. 相似文献
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The paper describes a model of an agricultural society in which agents live in a single settlement and use the surrounding area to produce essential and non-essential goods. Agents make, and attempt to fulfil, consumption and production plans but markets do not always clear and goods can change hands at different prices between different pairs of agents. The model generates a wide range of agricultural landscapes, including those of a classical von Thünen economy. Demographically, it produces outcomes varying from logistic growth to periodic collapse caused by cyclical famines. 相似文献
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Thomas Stegmaier Werner Wunderlich Tom Hager Abu Bakr Siddique J. Sarsour Heinrich Planck 《洁净——土壤、空气、水》2008,36(3):279-286
Chitosan, a natural polymer, was investigated as a possible sizing agent in fabric production by appropriate modification in the textile industry. Based on recipe developments at a laboratory‐scale, the ecological and economical potential of mainly cotton yarns were demonstrated and developed. Subsequent tests within the scope of industrial production confirmed the findings of the basic developments. As an interesting alternative to the conventional sizing process involving the removal of the size after weaving, the use of appropriate processing technologies makes it possible to apply chitosan in the form of a sizing agent resistant to wash‐out processes. Therefore, the wash‐out process and the combined wastewater loading can be avoided and the properties of chitosan can be used beneficially in the later applications of the fabric. The traditional method of sizing and weaving developments as well as the analyses of material recycling showed the possibilities of using closed circuits in textile production involving sizing agent and water. It is possible that a chitosan‐specific enzyme suitable for production conditions, which facilitates the wash‐out process in combination with the biodegradation of the wastewater in a sewage plant, could be developed. 相似文献
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A method is described for the determination of fifteen active ingredients of plant protecting products in ground-, raw, and drinking water. After extraction and enrichment of the pesticides from the water sample with solid-phase extraction, the extract is fractionated on silica-coated TLC plates, first in a so-called screening gradient by AMD (automated multiple development). The detection of the pesticides is performed by UV multidetection. Positive results from the first separation are confirmed by a second separation on silica in an AMD gradient of distinctly different selectivity, compared to the first separation. Following this strategy, it is possible to distinguish nearly all nonvolatile, from water extractable, active ingredients of plant protecting products in the market. UV spectra are taken for further confirmation of positive results. In most cases, this is possible even at the limit of determination. All chromatograms and spectra shown are raw data, resulting from the confirmatory test DIN 38407 part 11, in the laboratory of one participant*). The method is standardized in the meantime as DIN V 38407-11. 相似文献
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A method is described for determining the course of inhibition curves substantiating the influence of some inorganic (Cr (VI)) and organic substances (phenol, synthetic tanning agents) on respiratory activity of heterogeneous biomass (activated sludge). Presented results prove that calculated inhibition curves have the course of a normal distribution function. 相似文献
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多智能体与元胞自动机结合及城市用地扩张模拟 总被引：15，自引：3，他引：12
运用多智能体(Agent)和元胞自动机(CA)结合来模拟城市用地扩张的方法,将影响和决定用地类型转变的主体作为Agent引进元胞自动机模型中,Agent在CA确定的城市发展概率的基础上,通过自身及其周围环境的状况,综合各种因素的影响做出决策,决定元胞下一时刻的城市发展概率。运用Agent的决策结果,对CA模型中以随机变量体现的不确定性通过Agent决策行为给予地理意义的新解释。以城市郊区—樟木头镇为例,对1988～1993年城市用地扩张进行了模拟研究,取得了良好的模拟效果。 相似文献
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