Effects of red brick production on land use, household income, and greenhouse gas emissions in Khartoum, Sudan

In Khartoum (Sudan) a particular factor shaping urban land use is the rapid expansion of red brick making (BM) for the construction of houses which occurs on the most fertile agricultural Gerif soils along the Nile banks. The objectives of this study were to assess the profitability of BM, to explore the income distribution among farmers and kiln owners, to measure the dry matter (DM), nitrogen (N), phosphorus (P), potassium (K) and organic carbon (C_org) in cow dung used for BM, and to estimate the greenhouse gas (GHG) emissions from burned biomass fuel (cow dung and fuel wood). About 49 kiln owners were interviewed in 2009 using a semi-structured questionnaire that allowed to record socio-economic and variable cost data for budget calculations, and determination of Gini coefficients. Samples of cow dung were collected directly from the kilns and analyzed for their nutrients concentrations. To estimate GHG emissions a modified approach of the Intergovernmental Panel on Climate Change (IPCC) was used. The land rental value from red brick kilns was estimated at 5-fold the rental value from agriculture and the land rent to total cost ratio was 29% for urban farms compared to 6% for BM. The Gini coefficients indicated that income distribution among kiln owners was more equal than among urban farmers. Using IPCC default values the 475, 381, and 36 t DM of loose dung, compacted dung, and fuel wood used for BM emit annually 688, 548, and 60 t of GHGs, respectively.

Social housing and land use planning in Medellin during the period 2006-2011. Steps towards socio economic and residential segregation

This paper presents an approach to the relationship between land use planning and socioeconomic residential segregation, from the location of social housing in Medellin, Colombia, during the period 2006-2011. The first part introduces the land use regulations regarding the location of social housing, identifying ambiguities in the current spatial plan. Next, we present the intersection of  regulatory information and the location of the projects that were under construction during the  study period, highlighting the need to consider the location as an important characteristic of social housing and residential segregation as a phenomenon that must be recognized and worked on land  use planning in our cities.

Land use : photocopiable activities.

Las actividades de esta publicación son para apoyar la aplicación del plan de estudios nacional para la geografía, para niños de siete a once años, con especial referencia a la geografía humana. Los objetivos son introducir a los niños en la diversidad de usos de la tierra que se encuentra en las zonas rurales y urbanas; a examinar los diferentes tipos de uso de la tierra; para demostrar algunas de las formas en que surgen los conflictos por el uso de la tierra. Contiene una variedad de juegos, de composición abierta, investigaciones, rompecabezas, problemas de ejercicios y habilidades.

[Ressenya de la] Conferència internacional The Future of the Mediterranean Rural Environment: Prospects for Sustainable Land Use and Management. Menemen (Turquia), del 8 a l'11 de maig de 2000

Crònica de la conferència internacional 'The Future of the Mediterranean Rural Environment: Prospects for Sustainable Land Use and Management' sobre el desenvolupament sostenible de les àrees rurals mediterrànies. La conferència va tenir lloc entre el 8 i l’11 de maig de 2000 a Menemen (Turquia) i va reunir experts de diverses disciplines per establir els problemes principals que afecten la Mediterrània i per debatre mesures concretes de gestió, evitant o minimitzant els efectes negatius dels canvis econòmics, polítics, tecnològics i mediambientals recents

Applications of hydrodynamic and water quality models to the Sau and Boadella Reservoirs

Applicaciò d'un model de hydrodinàmica i de qualitat de l'aigua als embassaments de Sau i Boadella

Potential impacts of climate change on water quality and ecology in six UK rivers

A modelling study has been undertaken to assess the likely impacts of climate change on water quality across the UK. A range of climate change scenarios have been used to generate future precipitation, evaporation and temperature time series at a range of catchments across the UK. These time series have then been used to drive the Integrated Catchment (INCA) suite of flow, water quality and ecological models to simulate flow, nitrate, ammonia, total and soluble reactive phosphorus, sediments, macrophytes and epiphytes in the Rivers Tamar, Lugg, Tame, Kennet, Tweed and Lambourn. A wide range of responses have been obtained with impacts varying depending on river character, catchment location, flow regime, type of scenario and the time into the future. Essentially upland reaches of river will respond differently to lowland reaches of river, and the responses will vary depending on the water quality parameter of interest.

The Mersey Basin: an historical assessment of water quality from an anecdotal perspective

The freshwaters of the Mersey Basin have been seriously polluted for over 200 years. Anecdotal evidence suggests that the water quality was relatively clean before the start of the Industrial Revolution. The development of the cotton and chemical industries increased the pollution load to rivers, and consequently a decline in biota supported by the water was observed. Industrial prosperity led to a rapid population increase and an increase in domestic effluent. Poor treatment of this waste meant that it was a significant pollutant. As industry intensified during the 19th century, the mix of pollutants grew more complex. Eventually, in the 1980s, the government acknowledged the problem and more effort was made to improve the water quality. Knowledge of social and economic history, as well as anecdotal evidence, has been used in this paper to extrapolate the changes in water quality that occurred. (C) 2003 Elsevier Science B.V. All rights reserved.

Simulating SOC changes in 11 land use change chronosequences from the Brazilian Amazon with RothC and Century models

Land use and land cover changes in the Brazilian Amazon have major implications for regional and global carbon (C) cycling. Cattle pasture represents the largest single use (about 70%) of this once-forested land in most of the region. The main objective of this study was to evaluate the accuracy of the RothC and Century models at estimating soil organic C (SOC) changes under forest-to-pasture conditions in the Brazilian Amazon. We used data from 11 site-specific 'forest to pasture' chronosequences with the Century Ecosystem Model (Century 4.0) and the Rothamsted C Model (RothC 26.3). The models predicted that forest clearance and conversion to well managed pasture would cause an initial decline in soil C stocks (0-20 cm depth), followed in the majority of cases by a slow rise to levels exceeding those under native forest. One exception to this pattern was a chronosequence in Suia-Missu, which is under degraded pasture. In three other chronosequences the recovery of soil C under pasture appeared to be only to about the same level as under the previous forest. Statistical tests were applied to determine levels of agreement between simulated SOC stocks and observed stocks for all the sites within the 11 chronosequences. The models also provided reasonable estimates (coefficient of correlation = 0.8) of the microbial biomass C in the 0-10 cm soil layer for three chronosequences, when compared with available measured data. The Century model adequately predicted the magnitude and the overall trend in delta C-13 for the six chronosequences where measured 813 C data were available. This study gave independent tests of model performance, as no adjustments were made to the models to generate outputs. Our results suggest that modelling techniques can be successfully used for monitoring soil C stocks and changes, allowing both the identification of current patterns in the soil and the projection of future conditions. Results were used and discussed not only to evaluate soil C dynamics but also to indicate soil C sequestration opportunities for the Brazilian Amazon region. Moreover, modelling studies in these 'forest to pasture' systems have important applications, for example, the calculation of CO, emissions from land use change in national greenhouse gas inventories. (0 2007 Elsevier B.V. All rights reserved.

Parameter sensitivity and predictive uncertainty in a new water quality model, Q(2)

A new dynamic model of water quality, Q(2), has recently been developed, capable of simulating large branched river systems. This paper describes the application of a generalized sensitivity analysis (GSA) to Q(2) for single reaches of the River Thames in southern England. Focusing on the simulation of dissolved oxygen (DO) (since this may be regarded as a proxy for the overall health of a river); the GSA is used to identify key parameters controlling model behavior and provide a probabilistic procedure for model calibration. It is shown that, in the River Thames at least, it is more important to obtain high quality forcing functions than to obtain improved parameter estimates once approximate values have been estimated. Furthermore, there is a need to ensure reasonable simulation of a range of water quality determinands, since a focus only on DO increases predictive uncertainty in the DO simulations. The Q(2) model has been applied here to the River Thames, but it has a broad utility for evaluating other systems in Europe and around the world.

Managing land-use conflict around urban centres: Australian poultry farmer attitudes towards relocation

In analysing the release of agricultural land to urban development, the urban fringe literature has not focused on whether farmers are able to relocate from the urban fringe to remoter rural areas. Through interviews with representatives from the poultry industry in two Australian states, this paper identifies that poultry farm relocation strategies are constrained by off-farm economic relations, the land-use planning system and financial considerations. Closely aligned to these constraints on relocation is the on-going process of poultry farm intensification, which is seen as presenting rising problems for land-use management around expanding metropolitan centres in Australia. Of particular concern is the potential for amenity complaints and associated land-use conflicts, which have not been comprehensively investigated. Recognising that existing environmental and land-use planning controls are ineffective in producing amicable solutions when conflict involving poultry farming is at its most intense, the paper calls for improvements to the regulatory system, including greater consideration for how the process of relocation can be encouraged. (c) 2005 Elsevier Ltd. All rights reserved.

The water quality of the LOCAR Pang and Lambourn catchments

The water quality of the Pang and Lambourn, tributaries of the River Thames, in south-eastern England, is described in relation to spatial and temporal dimensions. The river waters are supplied mainly from Chalk-fed aquifer sources and are, therefore, of a calcium-bicarbonate type. The major, minor and trace element chemistry of the rivers is controlled by a combination of atmospheric and pollutant inputs from agriculture and sewage sources superimposed on a background water quality signal linked to geological sources. Water quality does not vary greatly over time or space. However. in detail, there are differences in water quality between the Pang and Lambourn and between sites along the Pang and the Lambourn. These differences reflect hydrological processes, water flow pathways and water quality input fluxes. The Pangs pattern of water quality change is more variable than that of the Lambourn. The flow hydrograph also shows both a cyclical and 'uniform pattern' characteristic of aquifer drainage with, superimposed, a series of 'flashier' spiked responses characteristic of karstic systems. The Lambourn, in contrast, shows simpler features without the 'flashier' responses, The results are discussed in relation to the newly developed UK community programme LOCAR dealing with Lowland Catchment Research. A descriptive and box model structure is provided to describe the key features of water quality variations in relation to soil, unsaturated and groundwater flows and storage both away from and close to the river.

Rainfall and runoff water quality of the Pang and Lambourn, tributaries of the River Thames, south-eastern England

The water quality of rainfall and runoff is described for two catchments of two tributaries of the River Thames, the Pang and Lambourn. Rainfall chemistry is variable and concentrations of most determinands decrease with increasing volume of catch probably due to 'wash out' processes. Two rainfall sites have been monitored, one for each catchment. The rainfall site on the Lambourn shows higher chemical concentrations than the one for the Pang which probably reflects higher amounts of local inputs from agricultural activity, Rainfall quality data at a long-term rainfall site on the Pang (UK National Air Quality Archive) shows chemistries similar to that for the Lambourn site. but with some clear differences. Rainfall chemistries show considerable variation on an event-to-event basis. Average water quality concentrations and flow-weighted concentrations as well as fluxes vary across the sites, typically by about 30%. Stream chemistry is much less variable due to the main Source of water coming from aquifer sources of high storage. The relationship between rainfall and runoff chemistry at the catchment outlet is described in terms of the relative proportions of atmospheric and within-catchment sources. Remarkably, in view of the quantity of agricultural and sewage inputs to the streams, the catchments appear to be retaining both P and N.

The water quality of the River Carnon, west Cornwall, November 1992 to March 1994: the impacts of Wheal Jane discharges

In January 1992, there was a major pollutant event for the River Canon and downstream with its confluence to the River Fal and the Fal estuary in the west Cornwall. This incident was associated with the discharge of several million gallons of highly polluted water from the abandoned Wheal Jane tin mine that also extracted Ag, Cu and Zn ore. Later that year, the Centre for Ecology and Hydrology (CBH; then Institute of Hydrology) Wallingford undertook daily monitoring of the River Canon for a range of major, minor and trace elements to assess the nature and the dynamics of the pollutant discharges. These data cover an 18-month period when there remained major water-quality problems after the initial phase of surface water contamination. Here, a summary is provided of the water quality found, as a backdrop to set against subsequent remediation. Two types of water-quality determinant grouping were observed. The first type comprises the determinants B, Cs, Ca, Li, K, Na, SO4, Rb and Sr, and their concentrations are positively correlated with each other but inversely correlated with flow. This type of water-quality determinant shows variations in concentration that broadly link to the normal hydrogeochemical processes within the catchment, with limited confounding issues associated with mine drainage. The second type of water-quality determinant comprises Al, Be, Cd, Ce, Co, Cu, Fe, La, Pb, Pr, Nd, Ni, Si, Sb, U, Y and Zn, and concentrations for all this group are positively correlated. The determinants in this second group all have concentrations that are negatively correlated with pH. This group links primarily to pollutant mine discharge. The water-quality variations in the River Camon are described in relation to these two distinct hydrogeochemical groupings. (C) 2004 Elsevier B.V All rights reserved.