نتایج جستجو برای: brown forest soil

تعداد نتایج: 321767  

2002
Robert F. Powers

Environmental policies in the United States and abroad are reducing timber harvests while wood demand is mounting. Reduced harvesting on public lands means that privately owned lands will be managed with greater intensity in the United States and that wood will be imported from other nations lacking strong environmental safeguards. It is imperative, therefore, that both public and private fores...

2012
P. Gundersen J. R. Christiansen G. Alberti N. Brüggemann S. Castaldi R. Gasche B. Kitzler L. Klemedtsson R. Lobo-do-Vale F. Moldan T. Rütting P. Schleppi P. Weslien S. Zechmeister-Boltenstern

Forests in Europe are changing due to interactions between climate change, nitrogen (N) deposition and new forest management practices. The concurrent impact on the forest greenhouse gas (GHG) balance is at present difficult to predict due to a lack of knowledge on controlling factors of GHG fluxes and response to changes in these factors. To improve the mechanistic understanding of the ongoing...

2011
D. W. Cole J. Compton P. S. Homann R. L. Edmonds H. Van Miegroet

Soil organic C or organic matter has been studied under various plant communities. In comparisons of similar soils having either grassland or forest vegetation, surface horizons of the forest soil may have lower levels of soil C (Ugolini and Schlichte, 1973; Almendinger, 1990) or higher levels (Jenny, 1980). Even between forest types, soil C may vary. Alban (1982) found the forest floor in a Po...

2016
Anna De Marco Antonietta Fioretto Maria Giordano Michele Innangi Cristina Menta Stefania Papa Amalia Virzo De Santo

This study focuses on two Mediterranean beech forests located in northern and southern Italy and therefore subjected to different environmental conditions. The research goal was to understand C storage in the forest floor and mineral soil and the major determinants. Relative to the northern forest (NF), the southern forest (SF) was found to produce higher amounts of litterfall (4.3 vs. 2.5 Mg·h...

Extended abstract 1- Introduction Changing the forests and pasture landuses to agricultural lands is one of the major global concerns about environmental degradation and climate change. As a result of the rangeland and forest changes into agricultural land and also tillage operations, about 430 million hectares, representing 30% of the world's total plowed land, are annually eroded and leavin...

Journal: :تحقیقات آب و خاک ایران 0
آرش کرمی کارشناسی ارشد، دانشگاه تهران قوام الدین زاهدی دانشیار، دانشگاه تهران جهانگیر فقهی دانشیار، دانشگاه تهران

some soil physical and chemical characteristics were analyzed in order to reveal the relationship between forest soils and regeneration patches. gorazbon district of kheyrud was selected as a case study for the research area. all regeneration patches were recorded using gps device. to assess the spatial structure and to quantify the metrics of regeneration patches, analyzing of landscape metric...

Journal: :محیط شناسی 0
محمدحسن امتحانی حمیدرضا عظیم زاده محمدرضا اختصاصی

prosopis cineraria (l.) druce (kahour in persian) is a native and indicative species of saharo-sindian region. prosopis forest in iran extends from the beach of persian gulf and oman sea in boushehr, hormozgan and sistan-baluchistan provinces to south of kerman province. in this research ecological conditions of prosopis such as floristic diversity, climate, soil and the biomass were studied. i...

2000
P. P. Motavalli H. Discekici J. Kuhn

The importance of the Northern Guam aquifer as a source of drinking water for the tropical Pacific island of Guam has stimulated public interest in the impact of forest clearing and conversion to agriculture on the region’s environment. The objectives of this study were to determine the effects of land clearing, tillage, and fertilization of tropical secondary forest on soil organic and organic...

Journal: :Environmental pollution 2002
L S Heath R A Birdsey D W Williams

The largest carbon (C) pool in United States forests is the soil C pool. We present methodology and soil C pool estimates used in the FORCARB model, which estimates and projects forest carbon budgets for the United States. The methodology balances knowledge, uncertainties, and ease of use. The estimates are calculated using the USDA Natural Resources Conservation Service STATSGO database, with ...

2004
Jouni Pulliainen Pertti Hari Martti Hallikainen Niina Patrikainen Martti Perämäki Pasi Kolari

The response of ERS-2 SAR to changes in soil and forest canopy moisture is investigated at a boreal forest test region in Finland. An inversion approach to estimate moisture characteristics from SAR data is applied. The method requires that a priori information on forest biomass (stem volume) and soil type distribution is available. The inversion technique provides estimates that are here, in a...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید