Terrestrial ecosystems

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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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  • The late Neogene (the period between − 14 and − 2.4 Ma) is one of the most interesting phases in understand the present conWguration of terrestrial ecosystems. It was during this time that the change took place from the middle Miocene dominant subtropical forests that stretched across southern Europe and western Asia to a more open but still wooded biotope that now prevails in warm–temperate areas. This change in vegetation, which strongly aVected the composition of mammalian faunas, seems to be linked to the rapid spread of grasses around 8–10 Ma ago....

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  • Tham khảo sách 'humic substances in terrestrial ecosystems', 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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  • Bioremediation, the use of microorganisms, by virtue of their bioconcentrating and metabolic properties, to degrade, sequester, or remove environmental contaminants, has about a 45-year history. Such uses of microorganisms for this purpose now involve freshwater, marine, and terrestrial environments. Bioremediation is a multidisciplinary area of knowledge and expertise that involves basic and applied science. Microbiologists, chemists, toxicologists, environmental engineers, molecular biologists, and ecologists have made major contributions to this subject....

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  • Natural resources conservation is one of the dilemmas currently facing mankind in both developed and the developing world. The topic is of particular importance for the latter, where the majority depend on terrestrial ecosystems for livelihood; more than one billion people live in abject poverty earning less than a dollar per day; more than 3.7 billion suffer from micronutrient deficiency and more than 800 million suffer from chronic hunger.

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  • This book addresses the significant environmental changes experienced by high latitude and high altitude ecosystems at the beginning of the 21st century. Increased temperatures and precipitation, reduction in sea ice and glacier ice, the increased levels of UV-radiation and the long-range transported contaminants in arctic and alpine regions are stress factors that challenge terrestrial and aquatic ecosystems.

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  • Ecosystems provide a wide variety of marketable goods, fish and lumber being two familiar examples. However, society is increasingly recognizing the myriad functions—the observable manifestations of ecosystem processes such as nutrient recycling, regulation of climate, and maintenance of biodiversity— that they provide, without which human civilizations could not thrive. Derived from the physical, biological, and chemical processes at work in natural ecosystems, these functions are seldom experienced directly by users of the resource.

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  • The idea for this book stems from a meeting sponsored by the European Union, organized by N. van Breemen, and held in Doorweerth at the end of 1991. At this meeting a large number of European scientists discussed the different issues related to the accumulation and decomposition of organic matter in terrestrial ecosystems. One of the objectives was to gather scientists from various disciplines (biologists, chemists, ecologists, agriculturalists) to pool their different disciplinary approaches and come up with a common perspective for future research on soil organic matter.

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  • Large herbivores are, and have for a long time been, among the major drivers for forming the shape and function of terrestrial ecosystems. These animals may modify primary production, nutrient cycles, soil properties, fire regimes as well as other biota. Some large herbivore species/populations are at the edge of extinction and great effort is being made to save them. Other species/populations are under discussion for reintroduction. Still other species occur in dense populations and cause conflicts with other land use interests.

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  • After completing this chapter, you will know: Why is biodiversity important? Make a list of some of the general reasons that animals and plants are endangered; how could a company (legally) develop land that is home to an endangered species? What is the most productive terrestrial ecosystem? What is the extent of deforestation globally? Where and how rapidly is it occurring? Contrast the different levels of ecosystem protection given to public lands in the United States; what is the tragedy of the commons? Give an example of a commons and how it is mistreated.

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  • The state of aquatic ecosystems reflects the general state of the biosphere. The situation in the biosphere affected by anthropogenic factors was characterized as “a slow explosion” (Fedorov 1987). The global change in the biosphere and climatic system of the Earth is a manifestation of this “slow explosion” (World Resources 1990–1991, Izrael et al. 1992).

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  • Plant species that invade an alien area and outgrow the native vegetation, establishing and increasing their own territory, often lead to negative economic, environmental, and social impacts. Even native species can behave like invasive species by their exponential spread. Similarly, not all non-native species are invasive. Many alien invasive species, however, do threaten the health and integrity of our terrestrial and aquatic ecosystems.

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  • Forest ecosystems cover large parts of the terrestrial land surface and are major components of the terrestrial carbon (C) cycle. Most important, forest ecosystems accumulate organic compounds with long C residence times in vegetation, detritus and, in particular, the soil by the process of C sequestration. Trees, the major components of forests, absorb large amounts of atmospheric carbon dioxide (CO2) by photosynthesis, and forests return an almost equal amount to the atmosphere by auto- and heterotrophic respiration.

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  • From the early explorers onwards, visitors to the Arctic and to Antarctica have commented with great interest on the presence of lakes, wetlands, and fl owing waters. These environments encompass a spectacular range of conditions for aquatic life, from dilute surface melt ponds, to deep, highly stratifi ed, hypersaline lakes.

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  • Soil provides a list of services to all users of terrestrial ecosystems and is crucial to our agricultural societies. From an anthropogenic point of view, soil quality may be then measured in terms of the services the soil provides to our society. The value of soil services to human societies has changed during history and thus the value we give to soils has also changed over time as it depends upon the economic and cultural basis of a society for a given context. While throughout history human awareness of the soil services has been mainly reduced to food, fibre and...

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  • This book proposes a framework for a national-scale program to monitor changes in mercury concentrations in the environment following the reduction of atmospheric mercury emissions. The book is the product of efforts initiated at a workshop held in Pensacola, Florida, in September 2003, involving more than 30 experts in the fields of atmospheric mercury transport and deposition, mercury cycling in terrestrial and aquatic ecosystems, and mercury bioaccumulation in aquatic food webs and wildlife.

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  • Pesticides are divided to insecticides, fungicides, herbicides, rodenticides, acaricides and nematocides according to the organisms that they affect. There are various forms of insecticides; most are repellants or insect growth regulators used in agriculture, public health, horticulture or food storage. It is evident that insecticides have been used to boost food production to a considerable extent and to control disease vectors.

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  • Soil is a biogeochemically dynamic natural resource that supports all critical components that comprise terrestrial ecosystems. It has been called Earth’s living skin. On its June 11, 2004, cover, Science declared soils to be “the final frontier.” The growing awareness that soil provides a variety of ecosystem services beyond food production has attracted interest in soil from nonsoil scientists.

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  • This report was prepared by a team led by Kathy MacKinnon (TTL), assisted by Valerie Hickey and Junu Shrestha (Biodiversity Team, ENV) with substantial material on adaptation in LAC from Walter Vergara, and contributions from Marjory‐Anne Bromhead, Christophe Crepin, Karsten Ferrugiel and Gayatri Kanungo (AFR); Emilia Battaglini, Maurizio Guadagni and Karin Shepardson (ECA); Joe Leitmann and Tony Whitten (EAP); Enos Esikuri, Marea Hatziolos, Claudia Sobrevila and Klas Sander (ENV); Gunars Platais, Adriana Moreira, Stefano Pagiola, Juan Pablo Ruiz, and Jocelyne Albert (LAC); Kanta Kumari R...

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  • The account measures the Total Ecosystem Accessible Fresh Water (TEAW) and the Net Ecosystem Accessible Fresh Water Surplus (NEAWS) adjusted for water stress during the vegetation growing season. Accounts in m3 are established for water stocks in terrestrial ecosystems (soil and vegetation) and water bodies (aquifers, lakes and dams, rivers). They include a distinction between total and accessible stocks, the difference being due to physical or economic constraints of abstraction, pollution or time mismatch between availability and requirements for natural or human uses.

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