8,487 research outputs found

    Final report on project SP1210: Lowland peatland systems in England and Wales – evaluating greenhouse gas fluxes and carbon balances

    Get PDF
    Lowland peatlands represent one of the most carbon-rich ecosystems in the UK. As a result of widespread habitat modification and drainage to support agriculture and peat extraction, they have been converted from natural carbon sinks into major carbon sources, and are now amongst the largest sources of greenhouse gas (GHG) emissions from the UK land-use sector. Despite this, they have previously received relatively little policy attention, and measures to reduce GHG emissions either through re-wetting and restoration or improved management of agricultural land remain at a relatively early stage. In part, this has stemmed from a lack of reliable measurements on the carbon and GHG balance of UK lowland peatlands. This project aimed to address this evidence gap via an unprecedented programme of consistent, multi year field measurements at a total of 15 lowland peatland sites in England and Wales, ranging from conservation managed ‘near-natural’ ecosystems to intensively managed agricultural and extraction sites. The use of standardised measurement and data analysis protocols allowed the magnitude of GHG emissions and removals by peatlands to be quantified across this heterogeneous data set, and for controlling factors to be identified. The network of seven flux towers established during the project is believed to be unique on peatlands globally, and has provided new insights into the processes the control GHG fluxes in lowland peatlands. The work undertaken is intended to support the future development and implementation of agricultural management and restoration measures aimed at reducing the contribution of these important ecosystems to UK GHG emissions

    Habitats of the World

    Get PDF
    Today it is not easy to talk about habitats and to think about the various threats facing them. We are living in an age in which we are poised between having everything immediately, and maintaining good living conditions on Earth. Unfortunately, this is almost impossible!For this reason it is important that everyone understands the importance of the habitats of the world and the inhabitants: including humans!This book aims to describe some of the world's habitats, their characteristics, and their daily threats. This is done in the hope that our children will see all of this tomorrow. Enjoy reading

    Do wind turbines impact plant community properties in mountain region?

    Get PDF
    International audienceThe emergence of renewable energy infrastructures calls for a better understanding of their impact on biodiversity. The aim of the present study was to investigate in a mountain region the impact of a wind turbine on plant communities in their vicinity. A field survey was conducted in a wind farm situated in the Southern Romanian Carpathians, five years after the turbines were installed. We tested for the effects of the presence of the turbine and the distance to the turbine on plant species richness, on five plant ecological indicators and on the quality of the pastures. Overall, 33 plant species belonging to 16 families were recorded, and among them 21 were recorded in both the presence and the absence of wind turbine. The presence of a turbine did not affect the structure of the plant community, as the majority of the plots exhibited similar plant species richness and composition. Finally, the values of the ecological indicators and the pasture quality were not altered by the presence of the turbine. Such analyses could be extended over longer time periods so as to capture potential long-term effects and by integrating other environmental factors such as microclimatic conditions or soil properties

    The classification and management of limestone pavements - an endangered habitat

    Get PDF
    This thesis describes an in-depth study of limestone pavements across North West England and North Wales. The aim was to combine elements of geodiversity and biodiversity in order to create a holistic limestone pavement classification to inform future management. A field-based research protocol was used to assess a stratified random sample (46 pavements), accounting for approximately 10% of the limestone pavements in the geographical area. Detailed analyses of key elements are presented, along with important issues that continue to pose threats to this Annex One Priority Habitat. This research resulted in a comprehensive classification, using TWINSPAN analysis and Nonmetric Multidimensional Scaling, identifying six distinct holistic functional groups. The prime factors driving limestone pavement morphology, and hence the classification, were established to be lithology, proximity to structural fault, altitude and human intervention, particularly in terms of grazing intensity. Three upland, open limestone pavement classes were formed. Of these, the richest in terms of geodiversity and biodiversity was the group with the thickest bedding planes and hence the deepest grikes, typically greater than 1m. The class that was most species-poor was "at the highest altitude (above 450m), formed on the thin limestones of the Yoredales. These were characterised by shallow, wide grikes. The third upland limestone pavement group had mid-range grikes, generally 0.5-1m in depth, and small clints. Two wooded classes were identified. One was a lowland 'classic' wooded limestone pavement group with deep, narrow grikes and shallow soils. Indicator species included Juniperus communis and Taxus baccata. The second wooded group was situated proximal to a major structural fault. In this group the pavement dip ranged between 10°-40° with well-runnelled clints that were heavily moss-covered. The sixth group was low altitude, proximal to the coast, characterised by low moss growth, un-vegetated clints and the presence of Ulex europaeus. Conservation management was identified as key to the quality of the limestone pavement habitat and this thesis identifies best management practises and links these to the holistic limestone pavement classification. Finally, as a sample case study, this thesis presents mollusc species and diversity from eleven of the Yorkshire limestone pavements. Analysis establishes significant links between geodiversity and mollusc populations, with key drivers for mollusc communities echoing those of plant species on limestone pavement.Funded by the Yorkshire Dales National Park and the University of Chester

    Patterns and controls of the latent and sensible heat fluxes in the brazilian Pampa biome

    Get PDF
    Energy and water exchange between the surface and the atmosphere are important drivers to Earth’s climate fromlocal to global scale. In thisstudy, the energy dynamic and the biophysical mechanisms thatcontrol the energy partitioning overa natural grassland pasture overthe Brazilian Pampa biome are investigated using two micrometeorological sites located 300 km apart, in Southern Brazil. The latent heatflux, LE, was the maincomponent of the energy balance in bothautumn-winter (AW)and spring-summer (SS)periods. Annually, approximately 60% of the available energy is usedfor evapotranspiration (ET). However, the Bowen ratio presents seasonal variability greater in AW than SS. Global radiation, Rg, is the atmospheric variable controlling LE and sensible heatflux, H. Hysteresis curves in the daily cycle wereobserved for ET and surface conductance, Cs, regarding the environmental variables, net radiation, vapor pressure deficit, and air temperature. Among the variables analyzed in the Pampa biome, surface conductance and evapotranspiration respond more strongly to the vapor pressure deficit. The hysteresis cycles formed by ET and conductance show a substantial biophysical control in the ET process. The results obtained here allowed a comprehension of the biophysical mechanisms involved in the energy partition process in natural grassland. Therefore, thisstudy can be usedas abasefor research on land-use changes in this unique ecosystem of the Pampa biome

    Fluxes of Energy and Water Vapour from Grazed Pasture on a Mineral Soil in the Waikato

    Get PDF
    The eddy covariance (EC) technique was used to measure half hourly fluxes of energy and evaporation from 15 December 2007 to 30 November 2008 at the Scott Research Farm, located 7 km east of Hamilton. Many other supporting measurements of climate and soil variables were also made. The research addressed three objectives: 1. To examine the accuracy of the eddy covariance measurement technique. 2. Understand the surface partitioning of energy and water vapour on a diurnal to annual timescale. 3. Compare measurements of evaporation to methods of estimation. Average energy balance closure at Scott Farm was deficient by 24%, comparable to published studies of up to 30%. Three lysimeter studies were carried out to help verify eddy covariance data. These resulted in the conclusions that; 1) lysimeter pots needed to be deeper to allow for vegetation rooting depths to be encompassed adequately; 2) forcing energy balance closure was not supported by two of the studies (summer and winter); 3) latent heat flux (λE) gap filling of night time EC data during winter over estimated values by about 10 W m-2; and 4) the spring lysimeter study verified eddy covariance measurements including the closure forcing method. Some uncertainty still exists as to the accuracy of both lysimeter and EC methods of evaporation measurement because both methods still have potential biases, however for the purpose of this study, it would appear data are sufficiently accurate to have confidence in results. Energy and water vapour fluxes varied on both a diurnal and seasonal timescale. Diurnally, fluxes were small or negative at night and were highest during the day, usually at solar noon. Seasonally, spring and summer had the highest energy and evaporation fluxes and winter rates were small but tended to exceed available energy supply. Evaporation was constrained by soil moisture availability during summer and by energy availability during winter. Estimated annual evaporation at Scott Farm was 755 mm, 72% of precipitation. Two evaporation models were compared to eddy covariance evaporation (EEC) measurements; the FAO56 Penman-Monteith model (Eo) and the Priestley-Taylor model (EPT). Both models over estimated evaporation during dry conditions and slightly under estimated during winter. The α coefficient that is applied to EPT was not constant and a seasonally adjusted value would be most appropriate. A crop coefficient of 1.13 is needed for Eo measurements during moist conditions. Eo began over estimating evaporation when soil moisture contents dropped below ~44%. A water stress adjustment was applied to both models which improved evaporation estimates, however early onset of drying was not able to be adjusted for. The adjusted Eo model is the most accurate overall, when compared to EEC

    Addressing Soil Degradation in EU Agriculture: Relevant Processes, Practices and Policies - Report on the project 'Sustainable Agriculture and Soil Conservation (SoCo)'

    Get PDF
    Agriculture occupies a substantial proportion of the European land, and consequently plays an important role in maintaining natural resources and cultural landscapes, a precondition for other human activities in rural areas. Unsustainable farming practices and land use, including mismanaged intensification as well as land abandonment, have an adverse impact on natural resources. Having recognised the environmental challenges of agricultural land use, the European Parliament requested the European Commission in 2007 to carry out a pilot project on "Sustainable Agriculture and Soil Conservation through simplified cultivation techniques" (SoCo). The project originated from a close cooperation between the Directorate-General for Agriculture and Rural Development (DG AGRI) and the Joint Research Centre (JRC). It was implemented by the Institute for Prospective Technological Studies (IPTS) and the Institute for Environment and Sustainability (IES). This report presents the findings of a stock-taking of the current situation with respect to soil degradation processes, soil-friendly farming practices and relevant policy measures within an EU-wide perspective. This overview includes the results of the survey on the national/regional implementation of EU policies and national policies, a classification of the described soil degradation processes, soil conservation practices and policy measures, and finally the outcome of the Stakeholder Workshop which took place on 22 May 2008 in Brussels.JRC.J.5-Agriculture and Life Sciences in the Econom
    • 

    corecore