Xem 1-20 trên 108 kết quả Forest area
  • Forests play an important role in reducing erosion. In Vietnam, destroying natural forests in mountainous areas has caused serious environmental problems for sustainable development. Required forest areas for protection of soils from erosion in Vietnam are defined in this study. An algorithm of defining required forest area for soil erosion prevention is based on a comparison of soil loss prediction and its threshold of 10 ton ha-1yr-1 (soil loss tolerance) within the GIS environment. Soil loss is predicted from rainfall erosivity index, slope, porosity and...

    pdf14p dem_thanh 22-12-2012 23 3   Download

  • The concept of forest sustainability dates from centuries ago, although the understanding of sustainable forest management (SFM) as an instrument that harmonizes ecological and socio-economic concerns is relatively new. The change in perspective occurred at the beginning of the 1990s in response to an increased awareness of the deterioration of the environment, in particular of the alarming loss of forest resources. The main and most striking cause of this deterioration is the deforestation occurring in some areas of the world.

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  • Sustainable forest management (SFM) is not a new concept. However, its popularity has increased in the last few decades because of public concern about the dramatic decrease in forest resources. SFM is generally implemented using criteria and indicators (C&I) that define forest management standards, and several countries have established their own sets of C&I within the framework of different international or regional processes. Nevertheless, none of the C&I systems have been universally accepted and future research should consider the current and future indicators....

    pdf468p wqwqwqwqwq 09-07-2012 31 13   Download

  • Forests play a major role in global carbon (C) cycle, and the carbon density (CD) could reflect its ecological function of C sequestration. Study on the CD of different forest types on a community scale is crucial to characterize in depth the capacity of forest C sequestration.

    pdf358p phoebe75 01-02-2013 30 12   Download

  • Hau Loc is a coastal district, located in the northeast of Thanh Hoa Province. its total natural land is 14,367.19 ha, 1.170 hectares of alluvial sites is suitable for planting forest and raise sea food. the The County has authorized 27 units (26 communes and townships 1). the total population of the district The year 2009 is 163.971 people, with density of 11.4 people per km2. The County has five coastal communes (Rhodes, Minh Loc, Ngu Loc, Hai Hung Loc and Loc) locate in East to the natural area is 3442.25 ha (accounting for 23.

    pdf0p xau_la 09-02-2012 39 9   Download

  • 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.

    pdf456p phoebe75 01-02-2013 21 8   Download

  • In 1950, the United States Department of Energy (then the U.S. Atomic Energy Commission) began purchasing the land that became the present Savannah River Site (SRS). All residents were removed (figure A), and in 1951 the government closed the site to the public to begin work on production of nuclear weapons materials. At the time, abandoned agricultural fields dominated upland areas, and the SRS and the USDA Forest Service initiated an aggressive reforestation program.

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  • The vascular flora of the Research Forest in Yen Tu, Quang Ninh was assessed between 2005 and 2006. In the area under review, 721 species belonging to 425 genera and 154 families were identified. Among these species, these are 9 Lycopodiophyta, 34 Polypodiophyta, 8 Gymnospermae and 670 Angiospermae species (577 Dicotyledonae, 93 Monocotyledonae). The richest 3 families are Euphorbiaceae with 52 (7.2%) species, Asteraceae with 30 (4.2%) species and Moraceae with 30 (4.2%) species. The richest genus is Ficus L., (22 species) followed by Syzygium Gaertn., (8 species) and Dioscorea L.

    pdf6p tuanloc_muido 11-12-2012 18 3   Download

  • Research objectives: Can analyze the current situation and characteristics of natural rehabilitation of flora carpet on lands after shifting cultivation as a basis for building the classification of rehabilitation capacity in the study area; can assess the protection capacity of flora carpet on lands after shifting cultivation, can classify rehabilitation potential of forest on lands after shifting cultivation through forest time natural rehabilitation, and propose some silviculture solutions for forest rehabilitation on lands after shifting cultivation in the watershed protection area.

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  • Several industries will need to contribute to successfully achieve this renewable resources vision. The Executive Steering Group therefore turned to a broad range of disciplines, including crop production, forestry, genomics, chemical processing, fermentation, industrial enzymes, materials science, biotechnology, plant physiology, and product manufacturing. The steering group sought input on key barriers, research goals, and interactions among related areas from more than 120 scientific experts and marketing professionals.

    pdf188p loixinloi 08-05-2013 28 10   Download

  • GynEndo News is the monthly newsletter of the International Society of Gynecological Endocrinology. GynEndo News is the best way to keep you updated in Gynecological Endocrinology. Receive every month scientific contents from Gynecological Endocrinology, the official journal of the Society, and from the international press. Let the relevant news in your area come directly to your e-mail, rather than looking for them...

    pdf0p le_minh_nha 18-12-2012 30 9   Download

  • Active in the area attacked by a large. The last chapter presents a simulation study collective behavior in disaster. I would like to express my special thanks to Mr. Igor Babic, Ivana Lorkovic her, and she Ivana ZEC. Last but not least, I want to thank the entire staff of Intech - Open Access Publishing, especially Mr. Igor Babic, professional support and technical support in all steps of the process that led to the realization of this book.

    pdf194p lulanphuong 24-03-2012 61 7   Download

  • Cross promotions among media companies, food sellers, and toy companies advance the corporate goal, as one marketing expert put it, “to establish a situation where kids are exposed to their brand in as many different places as possible throughout the course of the day or the week, or almost anywhere they turn in the course of their daily rituals” (Kjos, 2002). Supermarket shelves are filled with such links, such as Rugrats characters on packages of Kraft Macaroni & Cheese. Tie-ins like these are designed to lure children into...

    pdf102p dangsuynghi 15-03-2013 21 6   Download

  • Chapter 11 Soil Carbon Accumulation in Old-Growth Forests An area of 4.1 billion ha land is covered with boreal, temperate and tropical forest, together comprising up to 80% of the terrestrial aboveground carbon and 40% of total soil carbon

    pdf36p mama15 15-10-2010 52 5   Download

  • Chapter 18 Detecting Intact Forests from Space: Hot Spots of Loss, Deforestation and the UNFCCC Changes in forest cover have become recognised as an important global environmental issue. This chapter aims to synthesise what is known about areas and rates of forest-cover change in the tropics and boreal Eurasia from the 1990s onwards

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  • On the other hand, salinity affects 7-9 % of the world’s land area (Szabolcs, 1994), and the area is increasing (Ghassemi et al., 1995). Nowadays, one of the major technological goals of the energy production is the replacement of the fossil-based fuel for biofuel, mainly due to environmental issues. Bearing that in mind, it is mandatory to investigate the effect of water deficit and salinity stress in plant species with high potential for application in large scale production of nonfossil based fuels....

    pdf232p conquynho32 14-09-2012 36 5   Download

  • Many Roman villas had under-floor heating which would have been especially useful in the British winter! The Roman name, hypocaust, is Ancient Greek meaning ‘fire beneath’. The floor was supported on short columns made of stacked tiles. A fire would be kept burning (very hard work for the slaves!) in the furnace room, and the hot air would move through the under-floor area, heating the rooms above. The hot air and smoke escaped through channels in the walls. To make your hypocaust system, you will need to raise up your whole villa by around 6cm.

    pdf17p connhobinh 07-12-2012 15 5   Download

  • As shown in Table 2, the area of agricultural land worldwide is larger than that of forests (FAOSTAT Resources 2009). Furthermore, non-wood fibres usually have high annual biomass yields per hectare which are equal or superior to that of woods (Pierce 1991). Approximately 30% of the forest area is used primarily for the production of wood. An additional 24% of the forest area is designated for multiple uses, which also includes the production of wood in most cases (FAO 2010).

    pdf108p loixinloi 08-05-2013 17 5   Download

  • The cash flows diagram for the mexican CAT bond is described in Figure 4. CAT-MEX Ltd. issues the bond that is placed among investors and invests the proceeds in high quality assets within a collateral account. Simultaneous to the issuance of the bond, CAT-MEX Ltd. enters into a reinsurance contract with SRC. The proceeds of the bond will also serve to provide SRC coverage for earth- quakes in Mexico in connection with an insurance agreement that FONDEN has entered with the European Finance Reinsurance Co. Ltd., an indirect wholly- owned subsidiary of SRC.

    pdf0p enter1cai 16-01-2013 14 4   Download

  • Because time-series studies focus on a given geographic location over a number of years, factors that are often thought to influence the health of the population, such as percentage of smokers, income level, occupational exposure to pollutants, access to medical care and age distribution, do not need to be incorporated into the analysis as they are considered to remain relatively constant within the study area over time. Typically, the only other factors aside from pollution included in these models are weather variables and seasonal controls.

    pdf43p saimatkhauroi 01-02-2013 23 4   Download

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