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    ABSTRACT: Tour or trip chain based travel analysis has been a feature of transportation research for several decades, but has largely been the preserve of developed countries. Furthermore, the important associations between urban form and trip-chaining behaviour have received little attention. Based on detailed land use data and an activity dairy survey for workers in Beijing, China, this paper investigates how socio-demographic attributes of households, individuals and urban form characteristics at both residence and workplace, correlate with the tour-based travel decision process. We focus on tour frequency, tour scheduling (type and order of stops made) and tour interdependence mechanisms. Empirical results show that socio-demographic attributes and commuting time strongly correlate with tour decisions, but that there is no significant gender difference in tour frequency, as seen in developed countries, although women tend to make more stops within a tour. Urban form characteristics at home and at workplace are significantly associated with tour frequency, but differ with respect to tour complexity. For example, higher residential density is associated with more home-based tours with fewer stops, while mixed land use at workplaces having higher density and accessibility is associated with more stops within one work tour, or a more complex tour pattern. The research also reveals, for the first time, a tour interdependence effect for workers who undertake multiple tours.
    Habitat International 07/2014; 43:263–273. DOI:10.1016/j.habitatint.2014.04.008
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    ABSTRACT: This study focuses on identifying the future trends and spatial concentrations of morbidities in the English elderly population. The morbidities to be estimated are: coronary heart disease; strokes; diabetes; cancer; respiratory illnesses and arthritis in the 60 year and older household residential population. The technique used is a spatial microsimulation of the elderly population of local authorities in England using data from the 2001 Census and the English Longitudinal Study of Ageing. The longitudinal nature of the microsimulated population is then used to estimate the morbidity prevalences for local authorities in 2010/2011. With this knowledge, planners will be able to focus the available health and care resources in those areas with greatest need. For most of these morbidities, there is evidence of a strong correlation between the type of authority and the estimated prevalence rates.
    Health & Place 05/2014; 27:176–185. DOI:10.1016/j.healthplace.2014.02.010
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    ABSTRACT: The evolution in number, area and volume of ice-marginal lakes in western Greenland is very poorly documented or understood. It is important to understand ice-marginal lake evolution because they provide an element of meltwater retention, affect ice-margin character and behaviour, and potentially glacier dynamics. This study uses repeat satellite imagery acquired between 1987 and 2010 to reveal a net 44 % (± 6.5 %) increase in the number of lakes, a net 20 % (± 6.5 %) expansion in total lake surface area and an increase of 12% (± 3.3 %) in the estimated volume of meltwater retained along a 1300 km length of the ice margin in western Greenland. Whilst ~ 12 % (± 1.6 %) of the ice margin holds lakes at any one time there is considerable complexity in lake evolution; many lakes have coalesced, drained partially or fully, or become detached from the ice margin. The total lake volume equates to 144 % of the annual runoff combined from Gothab and Jakobshavn hydrological catchments. The rate of increase in meltwater retention between 1987 and 2010 was similar to the rate of increase in ice sheet surface runoff over the same time period. If the study region is representative of the whole Greenland ice sheet margin then as a first-order estimate ~ 5 % of the increased runoff over the last 25 years has been intercepted enroute to the oceans by the increased ice-marginal lake capacity. Interactions between these ice-marginal lakes, the western Greenland ice sheet and climate should be determined to provide insight into future land-terminating ice-marginal conditions, runoff retention and meltwater and sediment fluxes to the oceans.
    Global and Planetary Change 05/2014; 116. DOI:10.1016/j.gloplacha.2014.02.009
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    ABSTRACT: Developing low carbon cities is a key goal of 21st century planning, and one that can be supported by a better understanding of the factors that shape travel behaviour, and resulting carbon emissions. Understanding travel based carbon emissions in mega-cities is vital, but city size and often a lack of required data, limits the ability to apply linked land use, transport and tactical transport models to investigate the impact of policy and planning interventions on travel and emissions. Here, we adopt an alternative approach, through the development of a static spatial microsimulation of people’s daily travel behaviour. Using Beijing as a case study, we first derive complete activity-travel records for 1026 residents from an activity diary survey. Then, using the 2000 population census data at the sub-district level, we apply a simulated annealing algorithm to create a synthetic population at fine spatial scale for Beijing and spatially simulate the population’s daily travel, including trip distance and mode choice at the sub-district scale. Finally, we estimate transport CO2 emission from daily urban travel at the disaggregate level in urban Beijing.
    Computers Environment and Urban Systems 05/2014; 45:78–88. DOI:10.1016/j.compenvurbsys.2014.02.006
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    ABSTRACT: Understanding the ecohydrological responses of peatlands to climate change is particularly challenging over the late Holocene owing to the confounding influence of anthropogenic activity. To address this, a core spanning the last ∼2400 years from a raised bog in northern England was analysed using a comprehensive suite of proxy methods in an attempt to elucidate the drivers of change. A testate amoebae-based transfer function was used to quantitatively reconstruct changes in water table depth, supported by humification analysis and a plant macrofossil-derived hydroclimatic index. Pollen and plant macrofossil data were used to examine regional and local vegetation change, and human impacts were inferred from charcoal and geochemistry. Chronological control was achieved through a Bayesian age-depth model based on AMS radiocarbon dates and spheroidal carbonaceous particles, from which peat and carbon accumulation rates were calculated. Phases of both increased and decreased bog surface wetness (inferred effective precipitation) are present, with dry phases at c. AD 320–830, AD 920–1190 and AD 1850–present, and a marked period of increased effective precipitation at c. AD 1460–1850. Coherence with other records from across Northern Europe suggests that these episodes are primarily driven by allogenic climatic change. Periods of high bog surface wetness correspond to the Wolf, Spörer and Maunder sunspot activity minima, suggesting solar forcing was a significant driver of climate change over the last ∼1000 years. Following the intensification of agriculture and industry over the last two centuries, the combined climatic and anthropogenic forcing effects become increasingly difficult to separate due to increases in atmospheric deposition of anthropogenically derived pollutants, fertilising compounds, and additions of wind-blown soil dust. We illustrate the need for multiproxy approaches based on high-resolution palaeoecology and geochemistry to examine the recent trajectories of peatlands.
    Quaternary Science Reviews 01/2014; 84:65-85. DOI:10.1016/j.quascirev.2013.10.030
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    ABSTRACT: There is concern that ecosystem services provided by blanket peatlands have come under threat due to increasing degradation. Blanket peatlands are subject to a wide range of drivers of degradation and are topographically variable. As a result, many degradation forms can develop, including those resulting from eroding artificial drainage, incising gullies and areas of bare peat. Many degraded blanket peatlands have undergone restoration measures since the turn of the century. However, there has been little formal communication of the techniques used and their success. Using practitioner knowledge and a review of the available literature, this paper discusses the methodologies used for restoring sloping blanket peatlands. It then considers current understanding of the impact of restoration on blanket peatland ecosystem services. There is a paucity of research investigating impacts of several common restoration techniques and much more is needed if informed management decisions are to be made and funding is to be appropriately spent. Where data are available we find that restoration is largely beneficial to many ecosystem services, with improvements being observed in water quality and ecology. However, the same restoration technique does not always result in the same outcomes in all locations. The difference in response is predominantly due to the spatial and temporal heterogeneity inherent in all blanket peatlands. Peatland practitioners must take this variability into account when designing restoration strategies and monitoring impact.
    Journal of Environmental Management 01/2014; 133:193–205. DOI:10.1016/j.jenvman.2013.11.033
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    ABSTRACT: Catchment-scale land-use change is recognised as a major threat to aquatic biodiversity and ecosystem functioning globally. In the UK uplands rotational vegetation burning is practised widely to boost production of recreational game birds, and while some recent studies have suggested burning can alter river water quality there has been minimal attention paid to effects on aquatic biota. We studied ten rivers across the north of England between March 2010 and October 2011, five of which drained burned catchments and five from unburned catchments. There were significant effects of burning, season and their interaction on river macroinvertebrate communities, with rivers draining burned catchments having significantly lower taxonomic richness and Simpson's diversity. ANOSIM revealed a significant effect of burning on macroinvertebrate community composition, with typically reduced Ephemeroptera abundance and diversity and greater abundance of Chironomidae and Nemouridae. Grazer and collector-gatherer feeding groups were also significantly less abundant in rivers draining burned catchments. These biotic changes were associated with lower pH and higher Si, Mn, Fe and Al in burned systems. Vegetation burning on peatland therefore has effects beyond the terrestrial part of the system where the management intervention is being practiced. Similar responses of river macroinvertebrate communities have been observed in peatlands disturbed by forestry activity across northern Europe. Finally we found river ecosystem changes similar to those observed in studies of wild and prescribed forest fires across North America and South Africa, illustrating some potentially generic effects of fire on aquatic ecosystems.
    PLoS ONE 11/2013; 8(11):e81023. DOI:10.1371/journal.pone.0081023
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    ABSTRACT: Less than half of anthropogenic carbon emissions are accumulating in the atmosphere, due to large net fluxes into both the oceans and the land (Le Queré et al., 2012). The land sink in particular has increased markedly, doubling in strength since the 1960's, to reach 26 petagrams of carbon in the latest decade. However, the location and drivers of this large terrestrial sink are still relatively poorly constrained by atmospheric measurements (Ciais et al. 2013). Pan et al. (2011) recently utilised >1 million forest inventory plots to provide summaries of forest carbon stocks, and the first global bottom-up estimates of carbon fluxes for the world's forest biomes for the period 1990-2007. One key result was that almost all the residual global terrestrial carbon sink (i.e. carbon uptake after accounting for land use change), some 2.4 ± 0.4 Pg of carbon per year, is located in the world's established forests (Pan et al., 2011). The sink is distributed worldwide, with globally significant net fluxes into boreal and temperate forests, and a large sink in intact tropical forest, albeit with large uncertainty. Furthermore, Pan et al. (2011) showed that this tropical intact forest sink - may have faded from an estimated annual 1.3 ± 0.4 Pg C in the 1990's to 1.0 ± 0.5 Pg C for 2000-2007. The tropical intact sink is offset by a net land-use emission (1.5 Pg C yr(-1) [1990-1999]) declining to 1.1 Pg C yr(-1) [2000-2007]), and as a consequence aircraft measurements and inverse modelling studies indicate the tropics to be close to neutral in terms of net carbon fluxes (reviewed by Ciais et al. 2013). While the intact tropical forest sink values represent updates from similar values published previously (e.g., Lewis et al., 2009a), the fact that almost the entire residual terrestrial carbon sink is accounted for by the forests of the world was a notable discovery. Evidence from the ground now points to established forests being a net sink across almost every major forest region, including all extra-tropical forest regions analysed. This article is protected by copyright. All rights reserved.
    Global Change Biology 10/2013; 20(7). DOI:10.1111/gcb.12423
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    ABSTRACT: To project the ethnic-group populations of local authorities in England to 2051, estimates of ethnic-specific fertility rates were needed. In the absence of ethnic information on birth records, we developed indirect estimation methods that use a combination of vital statistics, the census (both microdata and aggregate tables), and survey data (Labour Force Survey). We estimated age-specific and total fertility rates successively for five broad ethnic groups encompassed by all data-sets, and for eight ethnic groups encompassed by the 1991 and 2001 Censuses for England. We then used census data to disaggregate the estimates to the 16 ethnic groups required for the subnational projections and the Hadwiger function to estimate single-year-of-age estimates. We estimated the uncertainty around the fertility estimates and used a logistic model to project rates to 2021, after which we assumed rates would remain constant.
    Population Studies 07/2013; 68(1). DOI:10.1080/00324728.2013.810300
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    ABSTRACT: Natural soil pipes are found in peatlands, but little is known about their hydrological role. This paper presents the most complete set of pipe discharge data to date from a deep blanket peatland in Northern England. In a 17.4-ha catchment, we identified 24 perennially flowing and 60 ephemerally flowing pipe outlets. Eight pipe outlets along with the catchment outlet were continuously gauged over an 18-month period. The pipes in the catchment were estimated to produce around 13.7% of annual streamflow, with individual pipes often producing large peak flows (maximum peak of 3.8 l s−1). Almost all pipes, whether ephemerally or perennially flowing, shallow or deep (outlets > 1 m below the peat surface), showed increased discharge within a mean of 3 h after rainfall commencement and were dominated by stormflow, indicating good connectivity between the peatland surface and the pipes. However, almost all pipes had a longer period between the hydrograph peak and the return to base flow compared with the stream (mean of 23.9 h for pipes, 19.7 h for stream). As a result, the proportion of streamflow produced by the pipes at any given time increased at low flows and formed the most important component of stream discharge for the lowest 10% of flows. Thus, a small number of perennially flowing pipes became more important to the stream system under low-flow conditions and probably received water via matrix flow during periods between storms. Given the importance of pipes to streamflow in blanket peatlands, further research is required into their wider role in influencing stream water chemistry, water temperature and fluvial carbon fluxes, as well as their role in altering local hydrochemical cycling within the peat mass itself. Enhanced piping within peatlands caused by environmental change may lead to changes in the streamflow regime with larger low flows and more prolonged drainage of the peat. Copyright © 2012 John Wiley & Sons, Ltd.
    Hydrological Processes 05/2013; 27(11). DOI:10.1002/hyp.9242
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