Xem 1-20 trên 29 kết quả Ecosystem principles
  • The variety of macrofauna in limnetic and estuarine ecosystems is related to the spatial arrangement of habitats with different quantitative and qualitative complexities (Heck & Crowder, 1991; Taniguchi et al., 2003; Genkai-Kato, 2007; Gullström et al., 2008). Among these habitats, submerged aquatic vegetation (SAV), harbour a high diversity of molluscs, macrocrustaceans and fish, by favouring a greater survival and growth of the associated populations (Minello & Zimmerman, 1991; Pelicice & Agostinho, 2006; Rozas & Minello, 2006; Cetra & Petrere, 2007; Genkai-Kato, 2007; Hansen et al.

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  • Tham khảo sách 'ecological engineering principles and practice', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả

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  • Human activities are affecting the global environment in myriad ways, with numerous direct and indirect effects on ecosystems. The climate and atmospheric composition of Earth are changing rapidly. Humans have directly modified half of the ice-free terrestrial surface and use 40% of terrestrial production. Our actions are causing the sixth major extinction event in the history of life on Earth and are radically modifying the interactions among forests, fields, streams, and oceans.

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  • England’s fisheries in 1871, Congress created the U.S. Commission of Fish and Fisheries (Hobart 1995). The first appointed Commissioner, Spencer Baird, initiated marine ecological studies as one of his first priorities. According to Baird, our understanding of fish “... would not be complete without a thorough knowledge of their associates in the sea, especially of such as prey upon them or constitute their food....” He understood that the presence or absence of fish was related not only to removal by fishing, but also to the dynamics of physical and chemical oceanography.

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  • Emission inventories play a dual role in global air pollution issues. Firstly, they can be used directly to establish the more important source categories, to identify trends in emissions and to examine the impact of different policy approaches. Secondly, emission inventories are used to drive atmospheric models applied to assess the environmental consequences of changing trace gas emissions and concentrations and to provide advice to policy makers. This second role contributes to the atmospheric modelling community being an important user of emission inventories.

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  • Dualism is a dominant theory of life that considers reality to be a balance between two independent and fundamental principles: good and evil, mind and matter, nature and nurture. In the same manner we see the thread of dualism run through the ecology of parasitism: they can generate diversity but cause extinction, they may castrate a host but increase its growth rate, and they can stimulate an immune response but at the same time encourage a secondary chronic infection.

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  • The soil ecosystem provides services such as carbon sequestration, nutrient cycling, water purification, provisioning of industrial and pharmaceutical goods, and a mitigating sink for chemical and biological agents. However, the soil is subject to various degradation processes. Its relation with the hydrosphere, biosphere, and atmosphere makes the interacting processes even more complex. Moreover, as the soilhuman interactions increase, threats, leading to a series of impacts on soil health, become more important....

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  • This text is intended as a graduate level introduction to the new field of ecological engineering. It is really a book about ecosystems and how they can be engineered to solve various environmental problems. The Earth’s biosphere contains a tremendous variety of existing ecosystems, and ecosystems that never existed before are being created by mixing species

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  • 1 Introduction Ecological engineering combines the disciplines of ecology and engineering in order to solve environmental problems. The approach is to interface ecosystems with technology to create new, hybrid systems. Designs are evolving in this field for wastewater treatment, erosion control.

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  • 5 Restoration Ecology Restoration ecology is a subdiscipline of ecological engineering that has been growing out of the need and desire to add ecological value to ecosystems that have been degraded by human impacts.

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  • 9 Conclusions These ecosystems, as we may call them, are of the most various kinds and sizes. A central theme of this book has been the development of the concept that new ecosystems can be designed, constructed, and operated for the benefit of humanity through ecological engineering.

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  • As resources become scarce, they become more valuable. Value is evidenced both by the increasing prices of resources and by controversy over resource allocation and management. From forest harvesting and land use conversion throughout North America, to the fragmentation of tropical bird habitat, to acid rain deposition in Eastern Europe, to Siberian tiger habitat loss in Russia, people have significantly affected the ecosystems of the world. Expanding population pressures continue to cause the price of resources to increase and to intensify conflicts over resource allocation....

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  • 8 Ecosystem principles have broad explanatory power in ecology 8.1 INTRODUCTION The criticism that ecology as a whole lacks universal laws and predictive theory is frequent, and there are authors who even argue that theoretical ecology concerned for instance with fitness and natural selection is not scientific

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  • 4 Microcosmology Microecosystems or microcosms are relatively small, closed or semi-closed ecosystems used primarily for experimental purposes. As such, they are living tools used by scientists to understand nature.

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  • 2 Treatment Wetlands The use of wetlands for treating wastewater is probably the best example of ecological engineering because the mix of ecology and engineering is nearly even. The idea is to use an ecosystem type (wetlands) to address a specific human need that ordinarily requires a great deal of engineering.

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  • 7 Exotic Species and Their Control The invasion of ecosystems by exotic species is a major environmental problem that has become widely recognized (Culotta, 1991; Mack et al., 2000; Malakoff, 1999). This phenomenon is occurring globally and causing changes to ecosystems, along with associated economic impacts.

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  • T his second edition provides an updated and expanded synthesis of feedbacks and interactions between insects and their environment. A number of recent studies have advanced understanding of feedbacks or provided useful examples of principles. Molecular methods have provided new tools for addressing dispersal and interactions among organisms and have clarified mechanisms of feedback between insect effects.

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  • Land management is presently undergoing enormous change: away from managing single resources to managing ecosystems. From forest to tundra, to desert, to steppe, the world’s ecosystems vary vastly. To manage them effectively we need to understand their geographic distribution better. We need to do this at various levels of detail because ecosystems exist at multiple scales in a hierarchy, from regional to local. Maps are needed to display ecosystem distribution and hierarchy. Until now, information on defining ecosystem boundaries has been scarce.

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  • The scientific literature suggests that the best unit to assess ecosystems is the 'socio-ecological system (SES)' (Gallopin, 1991, Glaser, 2008). SES integrates ecosystem functions and dynamics as well as human activities and the interactions of all these. The SES is equivalent to the SNA's institutional unit. Considering the production of ecosystem services, and in particular provisioning services, SESs are more or less homogenous.

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  • 9 Ecosystem principles have applications Tempus item per se non est, sed rebus ab ipsis consequitur sensus, transactum quid sit in aevo, tumquae res instet, quid porro deinde sequantur. Time per se does not exist: the sense of what has been done in the past, what is in the present and what will be is embodied in things themselves.

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