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Use of Fire in the Cerrado and Amazonian Rainforests of Brazil: Past and Present

Journal Articles & Books
Dezembro, 2011
Brasil

Humans have been changing the natural fire regimes in most Brazilian vegetation types for over 4000 years. Natural lightning fires can easily happen in savannas and grasslands, but they are rare in the moist rainforests. Today, anthropogenic fires are frequent in both the fire-adapted cerrado (Brazilian savanna) and the fire-sensitive rainforest. In this paper, I compare two very different biomes concerning their susceptibilities and responses to fire: the Amazon rainforest and the cerrado.

Improving landscape connectivity in forest districts: A two-stage process for prioritizing agricultural patches for reforestation

Journal Articles & Books
Dezembro, 2011
Espanha

Connectivity is a key concern in natural resource planning. Many studies have focused on the development of methods, tools and indices for the assessment of both components of connectivity: structural and functional. In particular, approaches based on graph theory principles have been recently proposed and are being increasingly applied to guide landscape connectivity conservation. However, forest planners and managers still need effective and operational methodologies to detect those landscapes where connectivity should be treated as a particularly critical conservation concern.

attribute-based approach to contingent valuation of forest protection programs

Journal Articles & Books
Dezembro, 2011
Estados Unidos

The hemlock woolly adelgid is an invasive insect that is damaging hemlock forests in the eastern United States. Several control methods are available but forest managers are constrained by cost, availability, and environmental concerns. As a result forest managers must decide how to allocate limited conservation resources over heterogeneous landscapes.

political ecology of land management in the oil palm based cropping system on the Adja plateau in Benin

Journal Articles & Books
Dezembro, 2012
Benim

The Adja plateau (Benin) is densely populated by tenant and landowner farmers engaged in oil palm based cropping. Landowners use oil palm sap for the production of sodabi (a local spirit), and an oil palm fallow (if no crops are grown beneath the palms) to restore soil fertility. In this area, growing oil palm for its oil is uncommon. Tenants access the land under specific contracts but are not allowed to plant oil palm.

Estimation of critical nutrient amounts based on input-output analysis in an agriculture watershed of eastern China

Journal Articles & Books
Dezembro, 2009
China

The concept of critical nutrient amounts (CNA) for a watershed was developed to address eutrophication in surface waters from diffuse (non-point) source pollution. CNA is defined as the maximum allowable applied or generated amount (AGA) of a nutrient from natural and human sources that can be emitted and still allow compliance with water quality standards.

USDA-ARS Riesel Watersheds, Riesel, Texas, USA: Water quality research database

Journal Articles & Books
Dezembro, 2014
Estados Unidos

"The 75 year legacy database including discharge, sediment loss, land management, and mete- orological data for the USDA-ARS Riesel Watersheds, Riesel, TX, USA has been available on the web for more than a decade (www.ars.usda.gov/spa/hydro-data) and used in numerous studies and publications; however, only recently have these data been added to the Sustaining the Earth’s Watersheds, Agricultural Research Data System (STEWARDS) database (www.nrrig.mwa.ars.usda.gov/stewards/

Effect of land use and management on soil bacterial biodiversity as measured by PCR-DGGE

Journal Articles & Books
Dezembro, 2010
África do Sul
África austral

Agricultural land use and sugarcane residue management effects on soil bacterial communities at two long-term sites in KwaZulu/Natal, South Africa, were investigated by PCR-DGGE. Land uses at site 1 were maize [M]; pre-harvest burnt sugarcane [SC]; permanent kikuyu pasture [KIK]; pine forest [PF]; wattle forest [W] and undisturbed native grassland [NAT], whereas land managements at site 2 were pre-harvest burning of sugarcane [Bto] or green cane harvesting with retention of a trash mulch [T] (with [F] or without [Fo] fertilizer additions).

Mapping wildland-urban interfaces at large scales integrating housing density and vegetation aggregation for fire prevention in the South of France

Journal Articles & Books
Dezembro, 2010
França

Every year, more than 50,000 wildland fires affect about 500,000 ha of vegetation in southern European countries, particularly in wildland-urban interfaces (WUI). This paper presents a method to characterize and map WUIs at large scales and over large areas for wildland fire prevention in the South of France. Based on the combination of four types of building configuration and three classes of vegetation structure, 12 interface types were classified. Through spatial analysis, fire ignition density and burned area ratio were linked with the different types of WUI.

Does flooding of rice fields after cultivation contribute to wetland plant conservation in southern Brazil

Journal Articles & Books
Dezembro, 2010
Brasil

Question: Does flooding of rice fields after cultivation contribute to wetland plant conservation in southern Brazil? Location: Rice fields in the coastal plain of southern Brazil. Methods: Six rice fields with different management practices were randomly selected (three dry rice fields and three flooded rice fields). Six collections were carried out over the rice cultivation cycle. Richness and biomass were measured using the quadrat method. Results: A total of 88 macrophyte species was recorded.