Environment Agency Wales

About: Environment Agency Wales is a based out in . It is known for research contribution in the topics: Population & Water quality. The organization has 29 authors who have published 27 publications receiving 1679 citations.

Main concepts of the "European approach" to karst-groundwater-vulnerability assessment and mapping

Abstract: In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe, a new approach is proposed by Working Group 1 of the European COST Action 620 on "Vulnerability mapping for the protection of carbonate (karst) aquifers". A general procedure is offered which provides consistency while allowing the required flexibility for application to a continent and under conditions of varying geology, scale, information availability, time, and resources.

Thinking like a fish: a key ingredient for development of effective fish passage facilities at river obstructions

Abstract: Worldwide, obstructions on watercourses have interfered with migratory pathways of fish species, reducing life-cycle success and often eliminating diadromous fish species altogether from river basins. Over the last century, efforts to mitigate these effects were initially directed at developing fishways for upstream, high-value migrant adult salmon. In more recent years, efforts have turned to developing fishways for other species. Results of past research suggest that the development of effective fishways requires biological knowledge of fish behaviour when encountering variable flows, velocity and turbulence, combined with hydraulic and civil engineering knowledge and expertise to develop facilities that provide appropriate hydraulic conditions that fish will exploit. Further, it often requires substantial financial resources for biological and hydraulic testing as well as engineering design, particularly where prior knowledge of the behaviour of target fish species does not exist. Where biological or engineering knowledge (or both) is absent, development of effective passage facilities must take on a trial and error approach that will almost certainly require years to attain success. Evaluations of existing adult and juvenile fish passage facilities, where they have been carried out, suggest that migrant fish reject areas with hydraulic conditions they determine unsuitable. Even well designed fish ladders or nature-like bypass channels for upstream migrants, even those with good attraction flows, will fail if incorrectly sited. Although progress has been made, developing successful installations for downstream migrants remains much more difficult, probably because downstream fish move with the flow and have less time to assess cues at entrances to any bypasses that they encounter. Copyright © 2011 John Wiley & Sons, Ltd.

Countryside Survey: National “Soil Change” 1978–2007 for Topsoils in Great Britain—Acidity, Carbon, and Total Nitrogen Status

Abstract: Understanding global environmental change is a major challenge for 21st-century science; monitoring and understanding national soil change is no exception. National scale monitoring results for soil pH, carbon, and total nitrogen status for Great Britain show that soil change is occurring on anthropogenic time scales and that environmental protection legislation is an important tool for reversing potential detrimental impacts. Understanding “soil change” at the national scale, in addition to soil status, is a key challenge for national scale soil monitoring programs and is essential if more sustainable use of this finite resource is to be achieved. We present results from the first national scale survey of soil change to be reported three times within Europe and perhaps globally, covering a 30-yr time span. Countryside Survey is an integrated national monitoring program that makes measurements of vegetation; topsoil physical, chemical, and biological characteristics (0–15 cm); water quality; and land use across Great Britain (GB), thus recognizing their interdependence. Here we report on change in fundamental soil chemical characteristics. Soil pH and loss on ignition (LOI) were measured in 1978, 1998, and 2007 and soil total nitrogen (total N) concentration and C/N ratio in 1998 and 2007. Bulk density was measured in 2007. Mean soil pH increased significantly in less acidic soils from 1978 through 1998 to 2007. Mean pH increased significantly in more acidic, organic-rich soils from 1978 to 1998 but not between 1998 and 2007, indicating spatial trends in both sulfur deposition reductions and soil sensitivity. There was a small increase (8%) in GB topsoil C concentration (calculated from LOI) between 1978 and 1998, a small decrease (6.5%) between 1998 and 2007, and no significant overall change between 1978 and 2007. The unresolved difference between these results and those from the National Soil Inventory of England and Wales that reported wide-scale large decreases in soil C concentrations in 2005 are discussed. There were unexpected small but significant decreases in total N concentration in many broad habitats despite continuing atmospheric nitrogen deposition. In seminatural and woodland habitats, this was accompanied by an increase in the C to N ratio, indicating one possible explanation is dilution of the nitrogen signal due to high C/N litter inputs resulting from increased primary productivity as reported elsewhere due to a range of global drivers such as increased CO2, N, and temperature. In arable systems, comparable rates of loss of C and N suggest erosion losses or deep plowing are reducing soil condition. The results are discussed in relation to the influences on soil processes of key drivers of environmental change and the importance of considering habitat-specific trends.