LandLessFood-green

Background and Objective

In 2100, food security is at risk in some regions of the world due to high population growth, extreme land scarcity and socio-economically precarious conditions. Sub-Saharan Africa will be particularly affected, where the population could increase fivefold by then and only 500 m2 of arable land per person would be available, even if all potential land is used. In addition to intensified food production, improved post-harvest protection and lower-loss utilization methods, improved use of crop residues also has the potential to help reduce hunger and/or poverty. So far, especially in Africa, crop residues are used by ruminants or as fuel. This is neither efficient nor sustainable. It is to be examined whether an alternative utilization by fungi and earthworms is more efficient and sustainable. With their help, valuable nutrients such as proteins, vitamins and minerals are to be produced from cereal and legume straw, for example. This production should be simple, land-saving, low-energy, climate-friendly and cost-effective. The leftover residues are to be returned to arable farming without pollutants and serve soil fertility:

1. ideas for effective production of additional food from residues (food energy, proteins, vitamins) with fungi and earthworms.
2. concepts for a sustainable and circular production of additional food from residues (climate, soil fertility, water, ...)
3. development of adapted technology ideas (micro to large scale, under difficult socio-economic and/or agro-ecological conditions).

Target Group

Poor people in low developed countries with farmland and food scarcities.

Approach

A model based on feeding one person using 500 square meters of available arable land was developed and empirically evaluated (Rahmann et al. 2020). From this, research questions were derived and experimentally addressed. The straw from various cereal crops (corn, wheat, rice) and legumes (soybeans, fava beans) was used to produce oyster mushrooms, earthworms, and vermicompost. To avoid conflicts of use, only straw of lower feed quality was utilized. Nutrient flows were carefully monitored, and the quality of the produced food, as well as the spent mushroom substrate and compost, was assessed. The focus was on carbon and nitrogen flows, protein content, and, in the case of earthworms, the amino acid composition. Different utilization paths for the straw (straw-mushroom-earthworm vs. straw-mushroom and straw-earthworm) were compared, and the implications for nutrient flows within the circular LandLessFood system were discussed.

In collaboration with the Thünen Institute of Agricultural Technology in Braunschweig, which is working on the LandLessFood-blue project focusing on using microalgae to process liquid residues, specific data for the LandLessFood model was provided.

Additionally, sustainable production methods, such as hot air pasteurization of mushroom substrate, were examined and further developed. To investigate the feasibility and potential of mushroom cultivation in an African country, a case study was conducted in Uganda.

The results of this research have been published in various scientific journal articles listed below, with some still in preparation for publication.

Our Research Questions

Research questions:

1. what is the efficiency, quality and quantity of food production from straw using fungi and earthworms?
2. what is the sustainability of circular food production from straw using fungi and earthworms (soil fertility, climate impact, Nutrient and Energy Cycle Assessment)?
3. what technology ideas can be proposed for different socio-economic and agro-ecological settings (example Africa: Uganda)?