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Remote sensing documentation of historic rangeland remediation treatments in southern New Mexico

Journal Articles & Books
Décembre, 2002
États-Unis d'Amérique

The Jornada Experimental Range and the New Mexico State University Chihuahuan Desert Rangeland Research Center are fruitful areas to study the long-term effects of rangeland remediation treatments which started in the 1930s. A number of diverse manipulations were completed under the direction of federal agency and university scientists, and abundant remote sensing imagery is available to assist in relocating the treatments and evaluating their success.

First-Order Fire Effects Models for Land Management: Overview and Issues

Journal Articles & Books
Décembre, 2010

We give an overview of the science application process at work in supporting fire management. First-order fire effects models, such as those discussed in accompanying papers, are the building blocks of software systems designed for application to landscapes over time scales from days to centuries. Fire effects may be modeled using empirical, rule based, or process approaches. Fire effects software systems can be used to conduct risk assessments, develop prescriptions for fuel treatments or prescribed fire, or support long-term planning.

Profiling forest fires along the urban gradient: a Mediterranean case study

Journal Articles & Books
Décembre, 2014
Grèce

The present paper assesses the spatial distribution and basic characteristics of 2,692 forest fires occurred along the urban gradient in a Mediterranean expanding region (Athens, Greece) during twelve years (2000–2011). Using descriptive, correlation and multivariate statistics, the study demonstrates that fringe fires significantly differ in size and frequency from peri-urban and rural fires, with the highest values recorded in the peri-urban belt (7.8 events/ha/year with an average size of 30.5 ha).

Natural Regeneration Processes in Big Sagebrush (Artemisia tridentata)

Journal Articles & Books
Décembre, 2014

Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change.

Land Management Impacts on Dairy-Derived Dissolved Organic Carbon in Ground Water

Journal Articles & Books
Décembre, 2008

Dairy operations have the potential to elevate dissolved organic carbon (DOC) levels in ground water, where it may interact with organic and inorganic contaminants, fuel denitrification, and may present problems for drinking water treatment. Total and percent bioavailable DOC and total and carbon-specific trihalomethane (THM) formation potential (TTHMFP and STHMFP, respectively) were determined for shallow ground water samples from beneath a dairy farm in the San Joaquin Valley, California. Sixteen wells influenced by specific land management areas were sampled over 3 yr.

Assessing the sensitivity of modelled estimates of N₂O emissions and yield to input uncertainty at a UK cropland experimental site using the DailyDayCent model

Journal Articles & Books
Décembre, 2014

Biogeochemical models such as DailyDayCent (DDC) are increasingly used to help quantify the emissions of green-house gasses across different ecosystems and climates. For this use they require parameterisation to represent a heterogeneous region or are site specific and scaled upwards. This requires information on inputs such as climate, soil, land-use and land management. However, each input has an associated uncertainty, which propagates through the model to create an uncertainty in the modelled outputs.

Determination of representative elementary areas for soil redoximorphic features identified by digital image processing

Journal Articles & Books
Décembre, 2011
États-Unis d'Amérique

Photography has been a welcome tool in documenting and conveying qualitative soil information. When coupled with image analysis software, the usefulness of digital cameras can be increased to advance the field of micropedology. The determination of a representative elementary area (REA) still remains a critical information need for soil scientists so that field measurements are independent of sample size and account for spatial heterogeneity.

Context for re-evaluating agricultural source phosphorus loadings to the Great Lakes

Journal Articles & Books
Décembre, 2011

Over the past decade, scientists have been discussing the re-emergence of harmful algal blooms and excessive growth of Cladophora in some areas of the Great Lakes. An observation that has emerged from these discussions is that management of non-point or diffuse sources of phosphorus will be more important in the future in order to address symptoms of eutrophication in the nearshore. This paper provides context for this renewed focus on managing non-point source tributary loads and is based primarily on materials and discussions from the Great Lakes P Forum.

Climate change and impact of desertification or soil/ land degradation in Turkey, combating desertification

Journal Articles & Books
Décembre, 2008
Turquie

The total arable land of Turkey is about 28,054,000 ha. The main income of the country is agriculture and agriculture based industry. However, the prime soils cover only 17.5% of the total land surface and the productivity of the rest of the soils is limited by topographical, chemical (e.g. high calcium carbonate content, alkalinity and low organic matter), and physical (e.g. water logging, texture) attributes. The diverse topography along with deforestation and unsuitable tillage and irrigation management has been inducing the rate of erosion in the country for centuries.