Characteristics of WWTP sludge after drying in greenhouse for agricultural purposes

The sludge generated by sewage treatment which meets regulatory standards can be used in agriculture. With this understanding, the focus of this study is the evaluation of the agricultural characteristics and inorganic substances in excess activated sludge, which was subjected to drying in a greenhouse. The variables (factor) evaluated during the drying process were: type of sludge (digested or not digested), addition of lime to the sludge, and the physical layout and rotation of sludge in the greenhouse. The parameters monitored for this assessment were moisture, volatile solids and pH. The greenhouse cover and sides were made of translucent plastic to allow the penetration of solar radiation and prevent water from entering. A impermeable floor was used. The sludge was generated in sewage treatment plants located in the metropolitan region of Grande Vitória, Espírito Santo, Brazil. The solar drying of wastewater sludge in a greenhouse presented satisfactory results.     

The economics of the private finance initiative

This article outlines and assesses the private finance initiativein the UK. The initiative has been slow to develop despite pressurefrom governments (anxious to limit the PSBR) and several revampsto facilitate the PFI approach. Within a PFI project there arebeneficial incentives to avoid cost over-runs but not to reducecosts where they affect long-run services. These incentivesand the limits to their effectiveness are explored. Such contractsrequire the transfer of risk from the public to the privatesector. the role and pricing of risk in the PFI is analysed.It is argued that the PFI does not value risk correctly andthat the value for money test is biased against private-sectorprovision. Policy implications are discussed, including a revampof the value for money test and the introduction of explicitassessment of the impact of potential renegotiation and othercontractual difficulties.     

Erosion Risk Mapping Applied to Environmental Zoning

Water erosion caused by inappropriate land use compromises the ecosystems and causes economic and social losses. To remedy this, the present study proposes (i) the evaluation of the erosion risk in an Environmental Protection Area (EPA) with the combination of Universal Soil Loss Equation (USLE), soil loss tolerance (T) estimates adapted to Brazilian soils and the legislation; and (ii) control measures from environmental zoning. This was applied to the EPA of Lageado stream, one of the main surface water sources in Campo Grande, Brazil. Several referenced information plans were overlapped and the total area was divided into five zones with different land use profiles, which were determined according to the conservation and preservation of native vegetation, occurrence of wet areas and springs, land use and management, eroded area recovery and occurrence of permanently preserved areas. The methodology proposed was suitable for environmental zoning of protected areas. This protocol can be applied to other areas by including additional variables such as social and economic parameters.     

Financial improvement planning in local governments in Southern Africa,with special reference to Zambia

Continuing decentralisation in most developing countries increases pressure on local governments to manage more functions and services and larger budgets. In this context, financial improvement planning (FIP) is a strategy that can be used by local governments wishing to improve or ‘fine‐tune’ their financial performance, and especially by those facing serious financial difficulties. This article examines the application of FIP in the town of Kitwe, Zambia, which faces financial difficulties within a national decentralisation framework characterised by several policy and fiscal deficiencies. The article covers how an FIP framework was developed, undertaken and the resultant interventions structured. Implications regarding the role, design and techniques of FIP in local governments within a decentralisation policy framework are elaborated upon. Effective decentralisation in southern African countries requires local governments to undertake sound financial management. In turn, this requires local governments to embrace challenging local policy processes. Development of FIP techniques, and strengthening local capacity and policy to support them in local governments, should be ingredients of any country's decentralisation programme.     

Model for Estimating the Time of Concentration in Watersheds

The time of concentration for a watershed is an essential parameter to the design of any hydrological project. In this study, a time of concentration estimation-model that uses variables obtained by monitoring rainfall-runoff events in a rural watershed of a tropical climate is proposed. In developing the model, the relationship between the time of concentration and independent variables was verified using a linear correlation matrix. Two variables with the highest correlation coefficient were selected to derive a model that can estimate the time of concentration. The Harmony Search (HS) optimization algorithm was employed to optimize the model parameters. The performance of the model was evaluated based on the Nash–Sutcliffe (NS) coefficient, which yielded a value greater than 0.80. The proposed model allows one to estimate the time of concentration using only the hydrograph of an event at the base level of a watershed, without the use of rainfall data.