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Environmental and Social-economic Impacts of Sewage Sludge Treatment by Guofeng Zhang download in ePub, pdf, iPad

The beneficial effects of sludge application on soil organic matter status, structural properties and soil moisture retention are also well documented. The major contributor to aquatic pollution in estuary and coastal areas is human sewage from population centres that is discharged from waste treatment plants. Indeed, one of the most commonly recognised environmental benefits is the recycling of phosphorus P in the food chain.

Sludge also provides other plant macronutrients, such as potassium and sulphur, and micronutrients such as copper and zinc. Current levels of sludge production The total quantities i. Sewage may affect the marine environment in three main ways, through oxygen depletion, causing disease, and by nutrient enrichment, which are discussed below. This study thus provides background information for a decision whether or not a revision of the directive is needed and lays the basis for a possible revision. The recycling of sludge to agriculture varies greatly among Member States.

This overview report summarises the main project results and forms Part I of the final report. This contributes to the conservation of mineral phosphorus reserves and also reduces external inputs of cadmium Cd present in phosphate rocks. Environmental, economic and social impacts of the use of sewage sludge on land. Sewage can contain disease causing bacteria and viruses which pose a risk to public health for swimmers and those eating contaminated shellfish. The second consultation reviewed the draft version of the Report on Options and Impacts and its preliminary cost-benefit analysis.

In addition to its use on agricultural land, sewage sludge has been employed successfully for forestry and in land reclamation operations, such as for disused mines or closed landfills. Key findings and results of the study are summarised in the following sections. The amounts of sewage entering the marine environment from recreational craft needs to be considered in perspective with the far greater amounts entering from land-based sources.

Bearing in mind that many yachtsmen use shore based marina facilities and some use holding tanks, recreational craft may be considered a minor contributor to sewage pollution. Sewage discharges also contain nutrients which when elevated slightly may increase algal and plant growth under certain background conditions.

Key findings and results of theIn addition to its