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Performance evaluation and cost assessment of a key indicator system to monitor desertification vulnerability

Journal Articles & Books
Dezembro, 2012
Europa
Sudoeste Asiático
África

A number of studies have dealt with the assessment of potential and actual desertification risk using composite indices. The Environmental Sensitivity Areas (ESA) approach, developed in the framework of MEDALUS project funded by the European Community, is one of the most used procedures to monitor land vulnerability to degradation in the Mediterranean region. The final output of this procedure is an index (ESI) composing four indicators of climate, soil, vegetation, and land management based on 14 elementary variables.

Post-1935 changes in forest vegetation of Grand Canyon National Park, Arizona, USA: Part 2--Mixed conifer, spruce-fir, and quaking aspen forests

Journal Articles & Books
Dezembro, 2011
Estados Unidos

This study examined changes in never-harvested mixed conifer (MCF), spruce-fir (SFF), and quaking aspen forests (QAF) in Grand Canyon National Park (GCNP), Arizona, USA based on repeat sampling of two sets of vegetation study plots, one originally sampled in 1935 and the other in 1984. The 1935 plots are the earliest-known, sample-intensive, quantitative documentation of forest vegetation over a Southwest USA landscape. Findings documented that previously described increases in densities and basal areas attributed to fire exclusion were followed by decreases in 1935-2004 and 1984-2005.

Seasonal and interannual variation in vegetation composition: Implications for survey design and data interpretation

Journal Articles & Books
Dezembro, 2014

Understanding how vegetation composition varies with season and interannual climate variability is important for any ecological research that uses vegetation data derived from surveys for the basis of inference. Misunderstanding this variation can influence land management and planning decisions, leading to poor implementation of biodiversity offsetting mechanisms, for example. We monitored plots (400 m²) grazed by livestock paired with adjacent ungrazed plots in derived native pastures four times a year over 2.5 years on the North‐West Slopes of New South Wales.

Assessing Administrative Laws for Forestry Prescribed Burning in the Southern United States: A Management-Based Regulation Approach

Journal Articles & Books
Dezembro, 2012
Austrália
Estados Unidos
América do Norte

SUMMARYPrescribed burning in forestry is a valuable land management tool that has been extensively used in Australia, Eurasia, and North America. Nevertheless, fire is inherently dangerous and may impose risk upon humans, properties, and other natural resources. With the case of southern United States, the objective of this study is to assess the trend of administrative law reforms for forestry prescribed burning within the theoretical framework of management-based regulation.

On the use of remote sensing techniques for monitoring spatio-temporal soil organic carbon dynamics in agricultural systems

Journal Articles & Books
Dezembro, 2012

Soil organic carbon (SOC) dynamics affect soil quality, agricultural productivity and atmospheric CO₂ concentration. Despite the need for spatial assessments of SOC content over time, reliable estimates from traditional field survey methods are limited by data availability; where measurements are often made at discrete point locations, at a coarse sample spacing or over a limited spatial extent.

Conservation of ecologically important and waterside areas with sustainable forage production

Conference Papers & Reports
Dezembro, 2014

From April to September 2014 the field experiment to determine responsiveness of plants to a depth of sowing and the economic and environmental value of dry matter yield on ecologically important and/or waterside areas was carried out in the valley of the river Pesnica (Zamarkova). The experiment was designed as split-plot with four replications. The plants treatments on main plots were: alfalfa (

Organization of territory in conditions of economy globalization with the use of bio-energetic approaches

Policy Papers & Briefs
Dezembro, 2011
Bielorrússia

In course of the research there were formulated the concepts, content and the main principles of territory organization in conditions of economy globalization. Bio-energetic approaches to its basing were suggested and their essence was shown. Methods of territory organization with the use of these approaches were presented. Indicators of estimation of territory organization variants and formulae for their calculation and developed the algorithm of territory organization were also shown.

Determinants of land use change: evidence from a community study in Honduras

Policy Papers & Briefs
Julho, 1999
Honduras

This study investigates the micro-determinants of land use change usingcommunity, household and plot histories, an ethnographic method that constructs paneldata from systematic oral recalls. A 20-year historical timeline (1975-1995) isconstructed for the village of La Lima in central Honduras, based on a random sample of97 plots. Changes in land use are examined using transition analysis and multinomiallogit analysis.

Relationship between soil δ¹⁵N, C/N and N losses across land uses in New Zealand

Journal Articles & Books
Dezembro, 2010
Nova Zelândia

Several of the major processes that result in N loss from soil (nitrification, ammonia volatilization, and denitrification) discriminate against ¹⁵N and fractionate the stable N isotopes, thus δ¹⁵N of ecosystem components has been suggested as an indicator of ecosystem N leakiness. This concept has been applied more successfully to native systems (primarily forest) than to managed systems where N inputs are greater and N cycling processes have potentially been modified.

Do Container Volume, Site Preparation, and Field Fertilization Affect Restoration Potential of Wyoming Big Sagebrush?

Journal Articles & Books
Dezembro, 2016

Land management practices, invasive species expansion, and changes in the fire regime greatly impact the distribution of native plants in natural areas. Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), a keystone species in the Great Basin, has seen a 50% reduction in its distribution. For many dryland species, reestablishment efforts have focused on direct seeding but achieved only minor success due to irregular seed germination and poor survival.

Modelling soil organic carbon dynamics in two long-term experiments of north-eastern Italy

Journal Articles & Books
Dezembro, 2007
Itália

Simulation models are widely used to assess the impacts of management and environmental variables on soil organic matter dynamics, to address questions on ecosystem sustainability and carbon cycling under global change. We tested the Century ecosystem model for two long-term experiments in north-eastern Italy: one (SF) comparing nutrient management treatments in small confined plots containing widely contrasting soil types (i.e., sandy, clay and peat) and the other (CR) involving a field study with crop rotation, nutrient, and management intensity variables.