Please use this identifier to cite or link to this item:
Main Title: Recycling Improves Soil Fertility Management in Smallholdings in Tanzania
Author(s): Krause, Ariane
Rotter, Vera Susanne
Type: Article
Language Code: en
Abstract: Residues from bioenergy and ecological sanitation (EcoSan) can be utilized to sustain soil fertility and productivity. With regard to certain cooking and sanitation technologies used in smallholder households (hh), we systematically analyzed how utilization of the respective potentials to recover residues for farming affects (i) soil nutrient balances, (ii) the potential for subsistence production of composts, and (iii) environmental emissions. On the example of an intercropping farming system in Karagwe, Tanzania, we studied specific farming practices including (1) current practices of using standard compost only; (2) a combination of using biogas slurry, urine, and standard compost; (3) a combination of using so-called “CaSa-compost” (containing biochar and sanitized human excreta, Project “Carbonization and Sanitation”), urine, and standard compost. The system analysis combines a soil nutrient balance (SNB) with material flow analysis (MFA). Currently, nitrogen (N) and phosphorus (P) are depleted by -54 ± 3 and -8 ± 1 kg·ha-1·year-1, respectively. Our analysis shows, however, a clear potential to reduce depletion rates of N, and to reverse the SNB of P, to bring about a positive outcome. Composts and biogas slurry supply sufficient P to crops, while urine effectively supplements N. By using resources recovered from cooking and sanitation, sufficient compost for subsistence farming may be produced. Human excreta contribute especially to total N and total P in CaSa-compost, whilst biochar recovered from cooking with microgasifier stoves adds to total carbon (C) and total P. We conclude that the combined recycling of household residues from cooking and from sanitation, and CaSa-compost in particular, is especially suitable for sustainable soil management, as it mitigates existing P-deficiency and soil acidity, and also restores soil organic matter.
Issue Date: 26-Feb-2018
Date Available: 1-Mar-2018
DDC Class: 629 Andere Fachrichtungen der Ingenieurwissenschaften
Subject(s): integrated plant nutrient management
counteracting soil nutrient depletion
biogas slurry
carbon recovery
ecological sanitation
vegan organic farming
Sponsor/Funder: DFG, TH 662/19-1, Open Access Publizieren 2017 - 2018 / Technische Universität Berlin
Journal Title: Agriculture
Publisher: MDPI AG
Publisher Place: Basel
Volume: 8
Issue: 3
Publisher DOI: 10.3390/agriculture8030031
Page Start: 1
Page End: 31
ISSN: 2077-0472
Appears in Collections:FG Kreislaufwirtschaft und Recyclingtechnologie » Publications

Files in This Item:
File Description SizeFormat 
agriculture-08-00031.pdf2.64 MBAdobe PDFView/Open

This item is licensed under a Creative Commons License Creative Commons