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

Journal Articles & Books
Diciembre, 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.

Informal institutions as mechanisms to address challenges in communal grazing land management in Tigray, Ethiopia

Journal Articles & Books
Diciembre, 2011
Etiopía

The role of institutions providing rules, norms and regulations, in addressing challenges in communal resources management has been debated for several decades. This article analyses the role of informal institutions for addressing shortage of grazing land, conflicts among users of communal grazing land and resistance among users to shift from free grazing to zero grazing in Tigray, Ethiopia. We used in depth interviews and focus group discussions for data collection.

Natural Regeneration Processes in Big Sagebrush (Artemisia tridentata)

Journal Articles & Books
Diciembre, 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
Diciembre, 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
Diciembre, 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
Diciembre, 2011
Estados Unidos de América

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
Diciembre, 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
Diciembre, 2010
Sudán

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
Diciembre, 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.