Exploring methodologies for assessing the outcome of soil management practices in Unilever's Sustainable Agriculture Code

Date
2020-03
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH SUMMARY : Agricultural soils are under immense pressure from modern farming practices, leading to unsustainable rates of degradation. Unchecked soil erosion and compaction reduce agricultural yields, while a loss of soil organic matter leads to a reduction in the soil’s capacity to sequester carbon, a key strategy to mitigate climate change. In recent decades, Voluntary Sustainability Standards (VSS) have been established to manage the health of soils and a range of other environmental and social impacts, providing safeguards that prohibit detrimental activities while promoting good agricultural practices. However, the effectiveness of these standards in meeting their objectives has been questioned, as the outcomes of prescribed practices usually go unmeasured. Unilever’s Sustainable Agriculture Code is a company-own VSS implemented globally with suppliers of a range of vegetables, fruits and cereals and other crops. Although this code contains measures to quantify some environmental impacts, there is no methodology to assess the outcomes of management practices for soil health. This thesis explores available methodologies to measure the outcomes of soil management practices, relating to soil compaction, erosion and soil organic carbon, with a particular focus on China and the United States. Barriers to adoption of methodologies by supply chain actors, as well as a system by which to capture and administer progress were also investigated. A systematic review of peer-reviewed and grey literature, as well as semi-structured interviews were methods used to explore these questions. It was determined that traditional in-field sampling and laboratory analysis methods were deemed unsuitable, except for the measurement of soil compaction. Instead, the Fieldprint Calculator’s soil conservation and soil carbon tools are suitable models to estimate soil loss and soil organic matter for farmers in the United States. The globally relevant Cool Farm Tool was considered a viable method to model the greenhouse gas emissions from farming, including carbon sequestered as the result of management practices. Finally, the SLAKES mobile application is considered an accessible tool to measure wet aggregate stability, a principle indicator of the erodibility of soil. Barriers to the adoption of these tools/methods by supply chain actors were also investigated, identifying the need for incentives like premiums and learning opportunities as a key lever to facilitating the participation of farmers. For Unilever, the selection of methods would need to consider objectives, weighing up contextual relevance with the benefits of standardisation and scientific rigour. Finally, the logical framework was identified as useful system by which to capture and administer performance against these methodologies, because of it’s ability to synthesise key components of the monitoring and evaluation process into a simple and transparent format.
AFRIKAANSE OPSOMMING : Moderne landboupraktyke plaas landbougrond onder geweldige druk en dit lei tot onvolhoubare degradasiekoerse. Ongekontroleerde grond-erosie en -verdigting verlaag landbou-opbrengste, terwyl ʼn verlies aan organiese materiaal in grond lei tot ʼn vermindering van die grond se vermoë om koolstof te isoleer, wat strategies noodsaaklik is om klimaatsverandering te versag. Oor die afgelope paar dekades is Vrywillige Volhoubaarheidstandaarde (VVS) vasgestel om grondgesondheid en verskeie ander maatskaplike en omgewingsinvloede te bestuur, deur voorsorg wat skadelike aktiwiteite verbied en goeie landboupraktyke bevorder. Hoe doeltreffend hierdie standaarde hulle doelwitte bereik, word egter bevraagteken, aangesien die uitkomste van die voorgeskrewe praktyke gewoonlik nie gemeet word nie. Unilever se Kode vir Volhoubare Landbou is die maatskappy se eie VVS, wat wêreldwyd deur die verskaffers van ʼn groot verskeidenheid groente, vrugte, graan en ander gewasse toegepas word. Hoewel hierdie kode maatreëls vir die kwantifisering van sommige omgewingsinvloede bevat, is daar geen metodologie vir die beoordeling van die uitkomste van bestuurspraktyke vir grondgesondheid nie. Hierdie proefskrif verken die metodologieë wat beskikbaar is om die uitkomste van grondsbestuurspraktyke ten opsigte van grondverdigting, -erosie en organiese koolstof in grond te meet, met spesifieke fokus op China en die Verenigde State. Hindernisse wat die toepassing van metodologieë deur spelers in die voorraadketting strem, en ʼn stelsel waardeur vordering vasgelê en geadministreer kan word, word ook ondersoek. ʼn Stelselmatige oorsig van gerefereerde en grys literatuur, asook semigestruktureerde onderhoude, is gebruik om hierdie vrae te ondersoek. Die tradisionele metodes van steekproefneming in die veld en laboratoriumontleding is as ongeskik beskou, buiten vir die meting van grondverdigting. In plaas daarvan is die grondbewarings- en grondkoolstofwerktuie van die Fieldprint Calculator beskou as geskikte modelle om grondverlies en organiese materiaal in grond vir boere in die Verenigde State te beraam. Die wêreldwyd-relevante Cool Farm Tool is beskou as ʼn haalbare metode om die kweekhuisgasvrystellings uit landbou, ingeslote die koolstof wat as gevolg van bestuurspraktyke geïsoleer word, te modelleer. Laastens is die SLAKES-selfoontoepassing beskou as ʼn toeganklike werktuig om die stabiliteit van nat aggregate, ʼn hoofaanduider van die erodeerbaarheid van grond, te meet. Hindernisse wat verhoed dat hierdie werktuie/metodes deur spelers in die voorraadketting gebruik word, is ook ondersoek, en aansporings, soos subsidies en leergeleenthede, is geïdentifiseer as noodsaaklik vir die fasilitering van boere se deelname. In sy keuse van metodes sou Unilever doelwitte in ag moet neem, en kontekstuele relevansie, saam met die voordele van standaardisering en wetenskaplike strengheid, moet opweeg. Laastens is die logiese raamwerk geïdentifiseer as ʼn nuttige stelsel vir die vaslegging en administrasie van prestasie op hierdie metodologieë, omdat dit die hoofkomponente van die moniterings- en beoordelingsproses in ʼn eenvoudige en deursigtige formaat saamstel.
Description
Thesis (MPhil)--Stellenbosch University, 2020.
Keywords
Sustainable agriculture -- Practice, Unilever Sustainable Agriculture Code -- Evaluation, Soil management, Soil productivity -- Measurement, UCTD
Citation