What to plant, when and where? - designing integrated forest-agricultural landscapes to enhance multiple livelihood benefits to and from agriculture

The overall aim of our project is to investigate biological and human well-being benefits provided by natural capital (sensu agroforestry) in tropical landscapes of Sub-Saharan Africa.

Integrated land management that exploits natural capital (e.g. natural and semi-natural habitats and their resources) for benefits to and from agriculture has been identified as a key component of sustainable agricultural intensification in Sub-Saharan Africa by academics and practitioners. Small-holder farmers traditionally recognise the benefits natural habitats can provide to agriculture. But research on underlying 'best practice' for improved crop yields is rare. Large knowledge gaps exist on the potential of natural capital for improving crop production whilst protecting biodiversity, clean water and resources such as timber, food, medicine and fuel. Data gaps are considerable on the biological mechanisms that underlie the benefits of natural capital for agriculture. Both knowledge and data gaps create perception challenges ('how useful is natural capital and is it necessary?) and these in turn hinders the targeted uptake of integrated land management for agricultural intensification in small-holder and industrial farms.

Our research will fill these gaps combining social and ecological method advances to quantify how and to what extent integrated landscape management can enhance benefits to and from agriculture. Working with rural farmers, agribusiness, development and education practitioners, research organisations and government in Tanzania, we will collect and analyse ecological and socio-economic data from our study landscape in Tanzania to address four key objectives. Our study landscape (~ 20 km x 40 km) encompasses part of a corridor along the border between the fragile forests of the Udzungwa Mountains and the productive croplands of the Kilombero Valley, a water catchment area and an important ecological hotspot. First, we will investigate the four key benefits provided by the study landscape: these include crop yields, soil health, biodiversity (in particular abundance of pollinators and natural enemies of pests and their interactions with food plants and habitats), and human-wellbeing. Second, we will investigate the spatial dependencies of these four benefits on natural and semi-natural habitats and their distribution in the landscape. Third, we will develop models that predict changes in these four benefits following restoration or loss of semi-natural and natural habitats in the study landscape. These will allow us to design landscapes and management that would maximise the four benefits. And fourth, we will investigate the drivers for decision-making by farmers and agribusiness on the management of farms and the wider landscape. We will develop a tool that allows us to visualise those drivers and how they translate into decision-making and subsequently into agricultural productivity.

Our project's research focus is on impact aiming to maximise the utilisation of natural capital for food security and human-wellbeing. This builds on the definition of sustainable resource as 'use of resources at rates that do not exceed the capacity of the Earth to replace them'. The research builds on evidence that agroforestry can substantially benefit crops, soil and biodiversity linked to pollination and pest control, whilst generating local (food, timber, firewood, medicine) and global (climate change mitigation, biodiversity conservation) environmental benefits. Our research will build on long-term partnerships established in the study landscape with farmers, agribusiness and government to achieve that impact.

Small-holder farming is the major livelihood activity of rural households in Sub-Saharan Africa; the majority lives below the poverty line and has faced food insecurity at certain times of the year. High yield gaps are pervasive on rain-fed farms exacerbating challenges farmers face. Yet, there are large uncertainties surrounding attainable crop yields, drivers of relative crop yields and environmental costs of solutions to closing yield gaps. These uncertainties are creating challenges for recent developments within developing countries with the spread of agricultural growth corridors and establishment of agribusiness. Our research project will collect and analyse ecological and socio-economic data in the Udzungwa Mountain Forests - Kilombero Valley study landscape, intersecting the SAGCOT agricultural growth corridor in Tanzania, working with in-country partners and co-investigators to address these uncertainties. The research will be co-produced. We will investigate the potential of agroforestry as integrated land management that can be used by farmers and agribusiness to improve crop production whilst retaining essential co-benefits ('understanding of the agronomic potential of natural capital'). Our main aim is to investigate the biological and human well-being benefits provided from retaining natural and semi-natural habitats in the landscape. We will identify and validate pathways to maximise multiple benefits through integrated landscape management ('Validate sustainable intensification strategies'). Our project is highly interdisciplinary using investigative biosciences to fill global knowledge gaps on crop yield and yield potential under multiple ecological and social constraints. We will investigate the cost-benefit trade-offs when using agroforestry for the sustainable intensification of agriculture. We will co-produce novel insight into the relationship between human-wellbeing and natural capital and how they inform decision-making.

This project will deliver, and build regional capacity in, research on the biological and human well-being benefits provided by natural and semi-natural habitats (i.e. natural capital) in forest-agricultural landscapes. This will enable regional policy makers and practitioners to devise and implement land management and governance interventions to tackle food insecurities, environmental degradation and associated well-being costs to rural farmers. The research will thus benefit rural poor populations affected by large-scale landscape transformations for a commercially viable agricultural sector in developing countries (i.e. agricultural growth corridors).

Building understanding of natural capital and analytical capacity for its multiple benefits to agriculture (including its potential and limitations) will increase planning capability at farm and landscape scales. This will complement industrial approaches to food security challenges, by recognising the full set of actors involved in the agricultural sector, their activities, motives and constraints, and the outcomes of their collective activities for crop production, and other socio-economic and environmental goals.

Specifically, we will deliver:
1. New knowledge on the agronomic potential of natural capital for improved crop yields, biodiversity and soil health benefits and sustainable human well-being.
2. New knowledge on the multiple trade-offs involved in land management for natural capital accounting for social and policy dimensions
3. Enhanced resilience of rural farmer livelihoods to environmental change and environmental shocks due to co-benefits provided by natural capita (i.e. access to clean water, timber and other products (i.e. medicine, fuel).
4. Improved health and well-being by reducing environmental costs arising from alternatively used agricultural interventions (i.e. the use of chemical fertilisation and pesticides).
5. Rural poor and local NGOs are empowered to participate in improved sustainable agricultural activities and land governance for multiple benefits protecting the interests of groups typically marginalised in agricultural transformation and investment.

The research will hence benefit a range of stakeholders across the agricultural and land management sector and additionally will look at the dynamic interactions between actors and their decision-making in a changing crop production system.
A. Rural farmers and households recognizing demographic, gender, socio-economic and cultural differences between different social groups in the study landscape.
B. Agribusiness producing substantial amounts of food and cash crops in Tanzania's main agricultural growth corridor SAGCOT (e.g. Kilombero Plantations Ltd, Kilombero Sugar Company, Kilombero Valley Teak Company)
C. National networks of farmers' groups (e.g. Mtandao wa Vikundi vya Wakulima Tanzania, Agricultural Non-State Actors Forum) that foster capacity building and undertake lobbying and advocacy to empower smallholder farmers economically and socially
D. Agricultural private sector organizations (e.g. Agricultural Council Tanzania).
E. NGOs: their research and capacity building. Local NGOs (COCO, Reforest Africa), International NGOs (e.g. ICRAF World Agroforestry Centre, The International Small Group Tree Planting Program TIST).
F. Policy community: National governments agencies and regulators with responsibility for agriculture, food, and natural capital management TFS Tanzania Forest Service, Tanzania National Parks Authority, Ministry of Agriculture, Food Security and Cooperatives); International Policy community (UN Sustainable Development Solutions Network, UN Major Group for Science and Technology, UN FAO, IPBES).
G. National and regional research capacity: agricultural colleges and research centres (e.g. Tanzania Agricultural Research Institute).