We assess whether tropical tree plantation expansion and forest regrowth across 18 African countries are associated with local people’s living standards. By combining a recent map that distinguishes tree plantations from regrowth from 2000 to 2012 with multidimensional poverty measures from more than 200,000 households, we find a positive association between people’s living standards and areas where tree plantations have expanded or, to a lesser extent, forest regrowth has occurred.
I am so excited to share at last some of the results from my PhD research on land use and nutrition, published today in Nature Food – Open Access! Here, we show how sourcing food from on-farm trees can benefit people’s diets in rural Malawi.
In countries like Malawi, where most rural households rely on rain-fed agriculture, people’s diets can depend on what crops they grow. Yet, policies designed to improve food security often focus on increasing the productivity of calorie-rich staple grains, which have done little to address the country’s high rates of malnutrition (as far more people suffer from micronutrient deficiencies than hunger).
Trees are an important source of nutrient-dense foods, yet if and how they can support dietary quality remains poorly understood. Through linking tree cover estimates from high-resolution satellite imagery with detailed food consumption data in Malawi, our research evidences how sourcing food directly from trees on farms can support women’s micronutrient adequacy across dry and wet seasons.
For example: Compared to women without food trees, women who sourced food from their own trees had on average 8-15% higher levels of zinc, vitamin A, iron and folate adequacy in the dry season, and 6-12% higher levels of zinc, vitamin A and folate adequacy in the wet season.
To tackle the interconnected problems of climate change, food insecurity, and biodiversity loss, we need solutions that address environmental and human health in tandem. It is clear that trees can and must play a role in such solutions.
Together with Prof. Ingo Grass from the University of Hohenheim in Germany – and 57 co-authors, we examined the effects of agricultural diversification strategies on both environmental and social outcomes. We did so by harmonizing data from 24 studies across 11 countries. We found that farmers who implemented multiple diversification strategies in tandem had more win-win outcomes.
Joint environmental and social benefits from diversified agriculture
Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system…
We examine the empirical relationship between having forests and trees in the surroundings and the probability of children consuming nutritious foods. We do so by combining detailed tree cover estimates based on PlanetScope imagery (3 m resolution) with Demographic Health Survey data from >15,000 households.
We find that even low levels of tree cover improve the likelihood of children aged 12–59 months consuming vitamin A–rich foods. Moreover, we observe that the effects of tree cover vary across poverty levels and ecoregions. The poor are more likely than the non-poor to consume vitamin A–rich foods at low levels of tree cover in the lowland forest-savanna ecoregions, whereas the difference between poor and non-poor is less pronounced in the Sahel-Sudan. These results highlight the importance of trees and forests in sustainable food system transformation, even in areas with sparse tree cover.
Even low levels of tree cover improve dietary quality in West Africa
Abstract. Forests are attracting attention as a promising avenue to provide nutritious and “free” food without damaging the environment. Yet, we lack knowledge
We show how forest regrowth in Nigeria has affected people’s dietary quality. We do so by combining a new map on forest regrowth with food consumption panel data from over 1100 households.
We use a a combination of regression and weighting analyses to generate quasi-experimental quantitative estimates of the impacts of forest regrowth on people’s food intake. We find that people living in areas where forest regrowth has occurred have a higher intake of fruits and vegetables and thus higher dietary diversity.
We examined monthly variation in women’s wild food consumption in two districts in India. After identifying that women most frequently consumed foods from forests and common lands in June and July, we estimated the contribution of wild food consumption to dietary diversity (a measure of diet quality), in these months. We used matching — a rigorous, quasi-experimental method — and regression analysis to isolate the causal relationship between wild food consumption and dietary diversity. Women who consumed wild foods were matched to women who did not consume wild foods on key socioeconomic, dietary and forest-level covariates – to ensure that differences in dietary diversity could be attributed to wild food consumption.
We found that women who consumed wild foods had higher average dietary diversity. In June, those women consumed an extra 0.34 food groups and, in July, they consumed an extra 0.30 food groups compared to women who did not consume wild foods.
Research on how to improve food and nutrition security has the potential to make real-life contributions for local communities suffering from nutrient deficiencies. Yet, most research remains inaccessible to people who could benefit from it. To elevate the impacts of research beyond a scientific paper, we co-developed a children’s book on wild foods. The book was shared with children in Malawi and Tanzania.
The book was co-developed with local communities in Malawi and Tanzania – and it takes point of departure in the findings obtained by PhD students Emilie Vansant and Rasmus Skov Olesen. Together they surveyed more than 1000 households across 16 sites in the two countries. The book is designed to educate young children in rural Africa about how wild foods from the forest can contribute to healthy diets. The illustrations were developed in collaboration with graphic facilitator Mette Jeppesen and highlight the importance of consuming foods rich in micronutrients, such as Vitamin A. To better acquaint children with their surrounding landscape, it features common tree species (e.g. wild custard apple, wild java plum) and green leafy plants (e.g. wild cow peas, black jack) and their various functions, including providing nutrient-rich fruits and vegetables.
The book was shared with ~1500 children across 16 schools in Malawi and Tanzania through interactive workshops designed to engage students with the book’s contents. When sharing the book, it was first read out loud together with the school children. Graphic Facilitator Mette sketched a human body and explained how eating nutritious fruits and vegetables can be good for your eyesight, strength and health. The workshops finished with a drawing activity, where the children picked certain leaves and fruits to draw together on large sheets of paper. These collective ‘nutritious landscape drawings’ were then used to decorate the classrooms.
