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1.
J Environ Manage ; 113: 117-27, 2012 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-23010623

RESUMO

Countryside Survey is a unique large scale long-term monitoring programme investigating stock and change of habitats, landscape features, vegetation, soil and freshwaters of Great Britain. Repeat field surveys combine policy and scientific objectives to provide evidence on how multiple aspects of the environment are changing over time, a key goal of international science in the face of profound human impacts on ecosystems. Countryside Survey 2007 (CS2007), the fifth survey since 1978, retained consistency with previous surveys, whilst evolving in line with technological and conceptual advances in the collection and integration of data to understand landscape change. This paper outlines approaches taken in the 2007 survey and its subsequent analysis and presents some of the headline results of the survey and their relevance for national and international policy objectives. Key changes between 1998 and 2007 included: a) significant shifts in agricultural land cover from arable to grassland, accompanied by increases in the area of broadleaved woodland, b) decreases in the length of managed hedges associated with agricultural land, as a proportion deteriorated to lines of trees and c) increases in the areas and numbers of wet habitats (standing open water, ponds) and species preferring wetter conditions (1998-2007 and 1978-2007). Despite international policy directed at maintaining and enhancing biodiversity, there were widespread decreases in species richness in all linear and area habitats, except on arable land, consistent with an increase in competitive and late successional species between 1998 and 2007 and 1978 and 2007. Late successional and competitive species: Stinging nettle (Urtica dioica), Hawthorn (Cratageous monogyna) and Bramble (Rubus fruticosus), in the top ten recorded species recorded in 2007, all increased between 1998 and 2007. The most commonly recorded species in CS (1990, 1998 and 2007) was agricultural Ryegrass (Lolium perenne). Increases in both water quality and soil pH were in line with policy aimed at addressing previous deterioration of both. Headwater streams broadly showed continued improvements in biological quality from 1998 to 2007, continuing trends seen since 1990. In soils, there were significant increases in soil pH between 1998 and 2007 consistent with recovery from acidification.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Solo/análise
2.
Int J Pept Protein Res ; 47(1-2): 47-55, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8907499

RESUMO

High-throughput analysis for purity and molecular weight determination of synthetic peptides including characterisation of any peptidic byproducts arising from synthesis is described. The data from electrospray mass spectrometry are processed with an algorithm that calculates the contribution of the target peptide and each of the identifiable contaminants to the total ionizable material in a sample of synthetic peptide. All essential data are obtained by one instrumental technique in < 3 min per sample. The technique has distinct advantages in the rapid analysis of the many hundreds of peptides/peptidomimetics required in systematic quantitative structure-activity relationship and other investigations.


Assuntos
Algoritmos , Espectrometria de Massas/métodos , Peptídeos/isolamento & purificação , Sequência de Aminoácidos , Modelos Lineares , Dados de Sequência Molecular , Peso Molecular , Peptídeos/síntese química , Peptídeos/química
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