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Malcolm Ausden - One of the best experts on this subject based on the ideXlab platform.
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grassland nature reserves for breeding wading birds in england and the implications for the esa agri environment scheme
Biological Conservation, 2002Co-Authors: Malcolm Ausden, G J M HironsAbstract:Abstract The two principal mechanisms available to conserve breeding wading birds on lowland wet grassland in England are nature reserves and agri-environment schemes, particularly the Environmentally Sensitive Area (ESA) scheme. ESAs offer payments to landowners in return for maintaining (‘low tiers’) or enhancing (‘high tiers’) the landscape, biodiversity and historic value of the land. Lowland wet grassland nature reserves managed by the Royal Society for the Protection of Birds (RSPB) have been successful at conserving breeding lapwings and redshank but habitat management usually only results in short-term increases in numbers of breeding snipe. Within ESAs, populations of breeding wading birds fare better on land managed under high tiers than on land managed under low tiers. Land managed under high tiers also supports more pairs of breeding wading birds per £ of ESA grant received than land managed under low tiers. Means of increasing the cost-effectiveness of the ESA scheme in conserving breeding wading birds are discussed in the light of these results.
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the effects of flooding lowland wet grassland on soil macroinvertebrate prey of breeding wading birds
Journal of Applied Ecology, 2001Co-Authors: Malcolm Ausden, William J Sutherland, Robert JamesAbstract:Summary 1 Lowland wet grassland in western Europe is often managed for breeding wading birds, especially lapwing Vanellus vanellus, redshank Tringa totanus, snipe Gallinago gallinago and black-tailed godwit Limosa limosa. Recommended conservation management often entails introducing winter flooding, and in Britain there is government funding to encourage this through the Environmentally Sensitive Area scheme. 2 Soil macroinvertebrates are important prey for breeding wading birds on lowland wet grassland. This study quantified the response of soil macroinvertebrates to flooding, their ability to survive in flooded grassland, and changes in the abundance and physical availability of soil macroinvertebrates for feeding wading birds as flood water subsides. 3 Unflooded grasslands contained high biomasses of soil macroinvertebrates, comprising mainly Tipulidae larvae and earthworm species that are widespread in pastures. Grasslands with a long history of winter flooding contained much lower biomasses of soil macroinvertebrates, comprising mainly a limited range of semi-aquatic earthworm species. 4 Introducing winter flooding to previously unflooded grassland greatly reduced soil macroinvertebrate biomass. This was mainly due to the majority of earthworms vacating the soil soon after the onset of flooding. However, when earthworms were artificially confined in flooded soils, most species were capable of surviving periods of at least 120 days continual submergence. Winter flooding also expelled large numbers of overwintering arthropods from the soil. 5 Soil macroinvertebrates were slow to recolonize winter-flooded grassland when it was re-immersed in spring. Consequently, prey biomass for breeding wading birds remained low in Areas that had been flooded during the preceding winter. However, winter flooding probably benefited breeding snipe by helping keep the soil soft enough for them to probe for prey. It also probably benefited breeding lapwings and redshank by helping keep the sward short and open enough for them to feed in during the latter part of their breeding season. Pools of winter flood water that remained in spring and early summer also provided a source of aquatic invertebrate prey for breeding wading birds. 6 We suggest that the best feeding conditions for breeding snipe will be provided by keeping the upper soil soft enough for them to probe in but without reducing soil macroinvertebrate biomass by flooding it beforehand. Optimal conditions for breeding lapwings and redshank will probably be provided by creating a mosaic of unflooded grassland, winter-flooded grassland and shallow pools.
G J M Hirons - One of the best experts on this subject based on the ideXlab platform.
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grassland nature reserves for breeding wading birds in england and the implications for the esa agri environment scheme
Biological Conservation, 2002Co-Authors: Malcolm Ausden, G J M HironsAbstract:Abstract The two principal mechanisms available to conserve breeding wading birds on lowland wet grassland in England are nature reserves and agri-environment schemes, particularly the Environmentally Sensitive Area (ESA) scheme. ESAs offer payments to landowners in return for maintaining (‘low tiers’) or enhancing (‘high tiers’) the landscape, biodiversity and historic value of the land. Lowland wet grassland nature reserves managed by the Royal Society for the Protection of Birds (RSPB) have been successful at conserving breeding lapwings and redshank but habitat management usually only results in short-term increases in numbers of breeding snipe. Within ESAs, populations of breeding wading birds fare better on land managed under high tiers than on land managed under low tiers. Land managed under high tiers also supports more pairs of breeding wading birds per £ of ESA grant received than land managed under low tiers. Means of increasing the cost-effectiveness of the ESA scheme in conserving breeding wading birds are discussed in the light of these results.
F. W. Kirkham - One of the best experts on this subject based on the ideXlab platform.
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the effects of nitrogen potassium and phosphorus addition on the vegetation of a somerset peat moor under cutting management
Journal of Applied Ecology, 1996Co-Authors: F. W. Kirkham, J O Mountford, R J WilkinsAbstract:1. A range of nitrogen (N), phosphorus (P) and potassium (K) fertilizer treatments was applied for 4 years in a randomized block experiment to a species-rich hay meadow on peat soil, within the Somerset Moors and Levels Environmentally Sensitive Area. 2. The percentage composition of each species present was recorded in May and October each year on plots cut for hay, followed by further cuts of aftermath growth. The effects on species richness, diversity and dominance were analysed, and ordination techniques were used to investigate the effects of fertilizers on plant community composition. Data for mean annual biomass production are also presented. 3. Botanical results were compared with those of a concurrent experiment where aftermath growth was grazed. 4. P was more important than N in determining both biomass production and botanical change. In both cases, the effects were small when substantial amounts of N and K were applied without P, but when high rates of P were included biomass increased very significantly and species diversity was severely reduced, with Holcus lanatus, Rumex acetosa and Lolium perenne dominating. 5. Lolium perenne was not increased by N and modest rates of P in the absence of aftermath grazing, but dominated all fertilized plots when aftermath grazing was maintained. Agrostis canina came to dominate plots receiving 200 kg ha -1 of N with modest rates of P and K in the absence of aftermath grazing, but was negatively associated with N where the aftermath was grazed. 6. Trifolium pratense became very abundant where P and K were applied with nil or 25 kg ha -1 of N each year, both with and without aftermath grazing, but all legumes were suppressed at high rates of N, particularly in conjunction with high P. 7. Substantial botanical change occurred on unfertilized plots as a result of the cessation of aftermath grazing. These plots became dominated by Plantago lanceolata, with significant increases in Leontodon hispidus and L. autumnalis.
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experimental assessment of the effects of nitrogen addition under hay cutting and aftermath grazing on the vegetation of meadows on a somerset peat moor
Journal of Applied Ecology, 1993Co-Authors: J O Mountford, K H Lakhani, F. W. KirkhamAbstract:Grassland on lowland peat has considerable potential for agriculture and conservation. The limited use of fertilizer on the Somerset Moors, designated as an Environmentally Sensitive Area has enabled the impact on vegetation of applying a range of nitrogen levels to be investigated using a randomized block experiment with large plots at Tadham Moor. From 1986 to 1990, the plot measurements each year included the individual percentage cover of some 100 species; these enabled the derivation of a number of measures of plant community structure. The applications of fertilizer encouraged grasses (notably Lolium perenne and Holcus lanatus) which came to dominate the sward at the expense of most other species (...)
George Panagopoulos - One of the best experts on this subject based on the ideXlab platform.
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monitoring sensitivity to land degradation and desertification with the Environmentally Sensitive Area index the case of lesvos island
Land Degradation & Development, 2016Co-Authors: Elias Symeonakis, Nikolaos Karathanasis, Sotirios Koukoulas, George PanagopoulosAbstract:In Europe, the most susceptible Areas to land degradation and desertification (LDD) are found in the Mediterranean region. The present study focuses on the island of Lesvos (Greece) and maps the environmental sensitivity of the island to LDD between the years 1990 and 2000. Sensitivity is estimated with a modification of the MEDALUS Environmentally Sensitive Area Index (ESAI) approach, employing 21 quantitative parameters divided in five main quality indices: climate, vegetation, soils, groundwater and socio-economic quality. Parameterisation of these indices is achieved via remote sensing and ancillary data in a Geographical Information System (GIS). Results show that ~85% of the island is fragile or critically Sensitive in both epochs. Fragile Areas are on the increase, covering an estimated 72% of the island in 1990 and 77% in 2000, whereas critically Sensitive Areas decrease from 214 to 113 km2. By modifying the ESAI to include 10 additional parameters related to soil erosion, groundwater quality, demographic and grazing pressure, and by applying the modified ESAI in two—rather than one—periods, this study was able to identify that, contrary to previous belief, critically Sensitive Areas are also found in the eastern side of the island mainly due to human-related factors. It is concluded that the proposed methodology is a useful tool for regional scale trend analyses of environmental sensitivity and the identification of LDD hot spots in Mediterranean environments. Copyright © 2014 John Wiley & Sons, Ltd.
Greg Mccomb - One of the best experts on this subject based on the ideXlab platform.
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British Columbia versus Canadian Forest Products: Estimating Nonmarket Damage to an Ecologically Sensitive Area
2015Co-Authors: Greg MccombAbstract:of British Columbia (B.C.). Two hundred and fifty hectares of this Area were classified as an Environmentally Sensitive Area, which means the trees are to be excluded from harvesting. The Area borders a stream that supplies local drinking water and supports fish populations. As a result of the fire, the Province of British Columbia sued Canadian Forest Products Ltd. to recover damages for the lost resources. In order to establish damages, the B.C. Court of Appeal needed to estimate the economic value of the protected trees. Justice Hall ruled that it would be unfair to assign full market value for trees never intended for market, so he awarded one-third of the market price to the B.C. government. This damage amount was appealed to the Supreme Court of Canada. The case was heard in October 2003, and a decision is expected within a year. This paper provides a rationale for why market prices alone underestimate the value of forests and hence, damage to them, by providing background information under the following topics: nonmarket valuation techniques, use of nonmarket valuation to support Environment Canada policies, relevant court cases, and nonmarket benefits of forests
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british columbia versus canadian forest products estimating nonmarket damage to an ecologically Sensitive Area
2005Co-Authors: Greg MccombAbstract:In 1992, a fire destroyed approximately 1500 ha of forest in the Prince George Forest District of British Columbia (B.C.). Two hundred and fifty hectares of this Area were classified as an Environmentally Sensitive Area, which means the trees are to be excluded from harvesting. The Area borders a stream that supplies local drinking water and supports fish populations. As a result of the fire, the Province of British Columbia sued Canadian Forest Products Ltd. to recover damages for the lost resources. In order to establish damages, the B.C. Court of Appeal needed to estimate the economic value of the protected trees. Justice Hall ruled that it would be unfair to assign full market value for trees never intended for market, so he awarded one-third of the market price to the B.C. government. This damage amount was appealed to the Supreme Court of Canada. The case was heard in October 2003, and a decision is expected within a year. This paper provides a rationale for why market prices alone underestimate the value of forests and hence, damage to them, by providing background information under the following topics: nonmarket valuation techniques, use of nonmarket valuation to support Environment Canada policies, relevant court cases, and nonmarket benefits of forests.