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close this bookBioconversion of Organic Residues for Rural Communities (UNU, 1979)
close this folderOrganic residues in aquaculture
View the document(introduction...)
View the documentIntroduction
View the documentThe range of production in aquaculture
View the documentThe value of organic wastes
View the documentDirect feeding
View the documentConcluding remarks
View the documentReferences
View the documentDiscussion summary

Introduction

The use of organic residues in aquaculture is best discussed with awareness of the following facts about aquatic biology: (i) Limitations to biological production in fresh, brackish, or ocean waters are predominantly dissolved nutrients and/or food as well as shelter or substrate. Seasonality and intensity of the input of solar energy are also important. Iii) In aquaculture (and incidentally in fisheries), what is eventually to be harvested has to be contained or concentrated.

Among these inputs, nutrients and/or food can be supplied, at least in part, by organic materials or residues. As aquacultural practices increase in magnitude and hasten the flow of materials and energy through the systems, compared to natural conditions, it stands to reason that fertilization wastes can, under certain conditions, save both monetary and caloric inputs. Likewise, judicious use of agricultural or organic industrial wastes as feed materials can lower the cost of growing aquatic animals. it is the purpose of this paper to describe the use of such practices and to discuss certain ecological, economic, and managerial conditions that determine or limit them.