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

Journal Articles & Books
Décembre, 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
Décembre, 2012
Australie
États-Unis d'Amérique
Amérique septentrionale

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
Décembre, 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.

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

Policy Papers & Briefs
Juillet, 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
Décembre, 2010
Nouvelle-Zélande

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
Décembre, 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
Décembre, 2007
Italie

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.

Ecology of Prestige in New York City: Examining the Relationships Among Population Density, Socio-economic Status, Group Identity, and Residential Canopy Cover

Journal Articles & Books
Décembre, 2014

Several social theories have been proposed to explain the uneven distribution of vegetation in urban residential areas: population density, social stratification, luxury effect, and ecology of prestige. We evaluate these theories using a combination of demographic and socio-economic predictors of vegetative cover on all residential lands in New York City. We use diverse data sources including the City’s property database, time-series demographic and socio-economic data from the US Census, and land cover data from the University of Vermont’s Spatial Analysis Lab (SAL).

Occurrence and assessment of organochlorine pesticides in the agricultural topsoil of Three Gorges Dam region, China

Journal Articles & Books
Décembre, 2015
Chine

Sixteen organochlorine pesticides (OCPs) were investigated in the 80 agricultural topsoil samples of Three Gorges Dam region, China. The concentration of OCPs ranged from 1.26 to 22.15 ng g⁻¹, with a mean concentration 6.49 ng g⁻¹. Dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) were predominant compared to other OCPs, with mean concentrations 1.80 and 1.27 ng g⁻¹, respectively, accounting for 28 and 20 % of the total OCPs. Ratio analysis indicated that there is new input of DDTs in this study area.