Salinization of Maputo’s horticultural soils

Participatory Agronomic Research:

Tackling the Salinity Issue of Maputo’s peri-urban Vegetable Farmers

„Piloting of Strategies to Mitigate Impacts of Salinity in Horticultural Systems of Mozambique“

Project Background

The idea to this project evolved some time back, in 2018 when Jakob and Matias conducted an exploratory field study on the prevailing issue of soil salinity within the peri-urban vegetable producing areas in Maputo, the capital of Mozambique. Jakob, one of our newest members at Weltweit, is a recent graduate of the master course ‘Agriculture and Resource Management in the Tropics and Subtropics‘ from  the University of Bonn. University contacts led him to Maputo and the ‘University Eduardo Mondlande’ (UEM), Mozambique’s most renowned educational institution, to realise his masters project. Its objective was to explore the causes, extent, and local perception of soil salinity within Maputo’s peri-urban vegetable production areas. The 10.000 plus farmers who cultivate the local coastal lowlands are ensuring the city’s supply with fresh vegetable produce. Unfortunately, they are constrained in their farming activities by several agronomic problems. While high pest pressure, unfavourable precipitation patterns (exacerbated by climate change effects) and constrained access to adequate farming inputs are rather well known and understood challenges, soil salinity is a hitherto hardly studied issue.

Jakob, in his research efforts, not only enjoyed crucial supervision by the ‘Faculty of Agronomy and Forestry Engineering’ of the UEM, but received equally strong support from Matias, representing the ‘Department of Agriculture, Livestock, Fisheries and Extension’ (DAPPE) of the Municipality of Maputo as its technical coordinator. Matias initially introduced Jakob to the local farmer organisations and its members, and eventually even became an active research partner, helping shape the study. He holds a Master degree in Soil Science from the University of Lavras in Brazil and has worked for DAPPE for 8 years. During this time, he has kept a foot in the field of agricultural sciences; having participated in several research projects as a consultant and working as a part time lecturer.

Jakob’s and Matia’s study, which was finally concluded in 2019, revealed that soil salinity indeed constitutes a major constraint to Maputo’s agricultural system. The local causes for salinization are complex; including hydrological mismanagement, urbanisation, sea-level rise and climate change aspects. Farmers are struggling with declining yields, complete degradation and loss of formerly agriculturally used land, along with a lack of capacity to sustainably manage the salinity problem. Looking for practical solutions to that dilemma, Jakob and Matias realised, however, that relevant application oriented agricultural research on salinity in the context of vegetable production is practically nonexistent. The vast available literature is restricted to fundamental research, mostly conducted in controlled greenhouse environments, and thus is barely geared towards direct applicability in smallholder farming contexts. Nonetheless, it indicates a large pool of potential agronomic solutions, including i.e. improved irrigation management (e.g. drip irrigation systems), mulching, adapted application patterns of composts, manures and conventional fertilizes, biofertilizer formulations, use of alternative salt tolerant crops, adapted cropping patterns and rotations. This realization constituted the actual starting point of our project. Jakob and Matias were interested in experimenting with management approaches as suggested by the pertinent literature and eventually identifying practical solutions adapted to the local farming realities.

Since then they forged ahead with turning this idea into reality. Following the elaboration of a detailed project plan, they looked for the right institutional partnerships and eventually brought together a consortium of 4 specialized institutions. DAPPE as the main implementing institution will be locally supported by ABIODES (represented through Alberto Luis), a Mozambican NGO experienced in offering agro-ecological extension services to farmers, as well as the ‘Faculty of Agronomy and Forestry Engineering’ of the UEM (represented through Professor Sebastião Famba). Weltweit assumes a coordinating function, supporting the project in terms of fundraising, public relations and the like. These initial efforts have been fruitful and we are looking forward to the project start in September 2020; grateful for the confirmed financial support of the ‘Conservation, Food & Health Foundation’ and the ‘Hand-in-Hand Fonds’.

In a nutshell, the principal objective of the project is to make the vast theoretical knowledge that exists on soil salinity and vegetable production tangible, and to put it into action. The project aims at a highly participatory approach and follows a modular logic. At the centre stands the combined realisation of Farmer Field Schools and scientific field trials. The idea is to actively involve representatives of the local farming community in the research and experimentation process. They will help select the agronomic approaches to be tested, take care of the experimental sites, and critically evaluate the experiments’ outcome. At the same time, the involvement of the UEM will ensure scientific tenability. Ideally, the project will lead to the identification and dissemination of feasible solutions for the local farming community, and concurrently generate generalizable scientific insights, thus contributing to pertinent international research and extension efforts. As a complementary module, the acquisition of modern mobile soil sensing equipment and the establishment of a GIS-based salinity monitoring system is envisaged. Such a system will allow the local authorities henceforth to make better informed land management decisions within Maputo’s valuable agricultural green belt.

The objective is to conduct the project’s experimental activities over several successive years and growing seasons; regularly informing here on its progress and milestones.

Initial Project Phase: August to December 2020

With a little luck and notwithstanding the constraints of the COVID-19 pandemic, we were able to kick-off our project activities as planned in the second half of 2020. The project start coincided with the good news of complementary funding granted by the ‘Development Cooperation of the State of Hesse’ (‘Entwicklungszusammenarbeit des Landes Hessen’). This allowed us, amongst others, to improve the technical endowment of our project initiative. Following the acquisition of specialized soil sensing and GIS equipment and it’s transport to Mozambique, which was realized by Jakob, the Mozambican project partners became busy, organising a series of training workshops on correct equipment usage and mobile mapping techniques for local extension staff, strategic soil sampling and analysis within the project area and pre-selection of potential sites for the envisioned field trials and Farmer Field Schools. For a more vivid and structured outline of our activities and the project’s initial phase please refer to the report attached below.

If you like to gain a detailed insight into the project area and its problem of soil salinity you can read the thesis of Jakob Herrmann:

The project plan that the partners have drafted together can be read here:

Now, at the beginning of 2021, despite slight delays, all project partners are optimistic and working with all strength towards the initiation of the experimental field activities scheduled for the beginning of the growing season in March/April.

Project Update: January to May 2021

Our project implementation largely continued according to plan. Having been delayed a bit, mainly due to persistent effects of the rainy season which had left vast areas of Maputo’s agricultural Green Belt inundated, the project team effectively resumed field activities in early April. Key aspects since then were the installation of our three field experimental sites and extensive technical networking. All activities of this project phase are documented in detail in the following report.

The partners in this project are:



This project is supported by:

Innovationsförderung Hessen