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Climate impacts on net primary productivity trends in natural and managed ecosystems of the central and eastern United States

Journal Articles & Books
Dezembro, 2009
Estados Unidos

The central and eastern United States is an important food and timber production region and could potentially be a large-scale carbon sink. These characteristics are functions of the human management of the landscape and favorable soil and climate conditions. Large-scale assessments of carbon uptake and trends in net primary productivity (NPP) have been previously reported for this region using satellite observations, but they cannot quantify the contributions from changes in management and technology independently from climate effects.

Possible impacts of climate change on water quality in streams of the Czech Republic

Journal Articles & Books
Dezembro, 2015
República Checa

The impacts of changes in water temperature and flow on selected water quality parameters, as one of the consequences of climate change, were studied in river catchments in the Czech Republic with little anthropogenic influence. The impact of climate change was manifested by an increase in stream temperature by 1.15°C over 28 years. The selected water quality parameters were dependent on flow, with up to 10-fold increases in the concentrations of ammonia, phosphorus and chlorophyll- a at minimum flow levels.

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
Dezembro, 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
Dezembro, 2011
Estados Unidos

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
Dezembro, 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.

Hop fields in crop rotation

Policy Papers & Briefs
Dezembro, 2010
Sudão

A number of factors influenced the increased number of crops on Slovenian farms legal limitation of maize production to two years on the same field, introduction of integrated crop production and certain measures of the Slovene Agri-Environmental Programme.

Use of Landsat 7 Enhanced Thematic Mapper Plus for Mapping Leafy Spurge

Journal Articles & Books
Dezembro, 2006

Euphorbia esula L. (leafy spurge) is an invasive weed that is a major problem in much of the Upper Great Plains region, including parts of Montana, South Dakota, North Dakota, Nebraska, and Wyoming. Infestations in North Dakota alone have had a serious economic impact, estimated at $87 million annually in 1991, to the state's wildlife, tourism, and agricultural economy. Leafy spurge degrades prairie and badland ecosystems by displacing native grasses and forbs.

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

Journal Articles & Books
Dezembro, 2002
Estados Unidos

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
Dezembro, 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
Dezembro, 2014
Grécia

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).