Tree Islands

Similar Names: applied nucleation, cluster planting, Assisted Natural Regeneration, Tree Island Planting

Tree islands, also known as “applied nucleation” or “cluster planting”, are a forest restoration technique that combines tree planting and natural regeneration. The primary goal of tree islands is to restore degraded landscapes by accelerating natural forest regeneration. It involves the strategic planting of small clusters of trees (“tree islands”), creating focal points for ecosystem restoration and accelerating natural regeneration in between the islands. They enhance natural forest recovery, rely on animal species for the dispersal of native tree seeds, and promote high levels of native biodiversity. 

The tree islands act as biodiversity hotspots, improving soil fertility, water retention, and microclimate, creating resilient ecosystems. They increase the availability of tree seeds and attract seed dispersers. They also provide shade, suppressing sun-loving plants that can overgrow in the area,  leaving no space for trees to establish. By creating tree islands, a base is offered from which the forest can re-establish itself and grow back much faster than conventional natural regeneration approaches.

Overall, tree islands represent an innovative and promising approach to forest restoration, offering a sustainable method for accelerating the recovery of temperate, tropical, and subtropical forests. It is a cost-effective forest restoration technique that uses only about 20% of the trees that would be needed for a whole forest plantation of the same area. This makes it more accessible and the structure more natural.

When implementing this intervention in a certain area, it is best to involve the community. It can even become a community-driven initiative, with community members working on the implementation, monitoring, and maintenance of the tree islands. This enables them to play an active role in local forest regeneration.

Swales

A swale is an intervention designed to retain water run-off on a slope. It is a long, small ditch on the contour lines, i.e. at the same elevation. Several swales can be constructed next to each other to increase their effect. Swales have a small berm on the downslope side, which often contains vegetation and acts as a retaining wall.

Swales are cost-effective and relatively easy to implement, preventing soil erosion, nutrient run-off, and flooding. They capture water which runs down the hill and let it infiltrate into the soil. Growing vegetation on the berm will strengthen the berm and the soil and will hold water and nutrients better. Trees, in particular, work well for strengthening berms and are watered by the water held by the swales. If possible, it is also an option to add stones to a berm to make it even stronger. In the Perma Atlas Initiative, swales have been a great success in preventing flooding. Swales are similar to Contour Bunds and Fanya Chini and they can be used on a small or large scale. The greatest reduction observed when swales are introduced are in water runoff, soil loss, phosphorus runoff and nitrate-nitrogen runoff.

Grass Seed Banks

Similar names: Community Seed Banks (also for other seeds)

Grass Seed Banks are a conservation and restoration strategy aimed at revitalizing degraded landscapes, particularly in arid and semi-arid regions. Communities can decide where they are suitable and establish them in degraded areas of about ten hectares. Grass Seed Banks are sowed with grass seedlings and should be naturally fenced using shrubs to protect the grasses against grazing livestock and wildlife. These seed banks serve as repositories of native grass seeds, which are essential for restoring vegetation cover in areas affected by desertification, land degradation, and biodiversity loss. They are a community-based initiative that restores degraded landscapes and provides economic opportunities for local communities, especially women. Grass Seed Banks can be managed and maintained by local women’s groups, who sow and harvest the grand grass seeds. Once the grasses are fully grown, they produce grass seeds, which the women can sell at local markets (for example to other restoration projects) or as fodder for livestock.

By selling the grass seeds, women can earn additional income. When grass seed bank projects are successful, the status of the women in the community can be improved. Selling the grass seeds can also help other restoration projects and thereby help to regreen other areas as well. Moreover, they can help to attract insects and small animals, which boosts local biodiversity and the growth of vegetation in the area around the seed banks.

Fencing

Fencing around eroded soils, rills and gullies is a cheap and low-maintenance form of sediment catchment, soil and water runoff prevention on gentle, moderate and steep slopes. Three types of fencing are detailed in this intervention about their prevention of different types of soil erosion at varying topographies.

  1. Silt Fences → Softer intervention for sediment catchment, preventing runoff and wind displacement on rills, arid fields or gentle hillsides. 
  2. Woven Fences → Harder intervention for slope stabilisation and sediment build-up in gullies and rocky mountainous landscapes.
  3. Biotrampas → Harder intervention for rock catchment, landslides and slope stabilisation in gullies and heavily eroded, steep mountainous landscapes.

Kitchen Gardens

Similar names: Community Gardens, Permagardens, Permaculture Gardens, Vegetable Gardens, Urban Gardens

Kitchen Gardens consist of pieces of land close to households in which plants such as vegetables, herbs and fruits for use in the kitchen are cultivated. These gardens can include space for livestock, (fruit & nut) trees and hedges cultivated for fodder. Kitchen Gardens have long been practised to provide subsistence and a variety of food for small households, whilst also providing an additional source of income when surpluses are generated and sold at the market. With a few adjustments, this practice can be adapted to most kinds of ecosystems, and even in highly urbanised areas, with the aid of pots and containers. This intervention is most suitable for flat or gently sloped terrains (0-5%), however, to obtain a lower slope in hillside conditions, it can be combined with Eyebrow Terraces. Gardens can also be created in schools and other public facilities, involving the entire community.

Kitchen Gardens offer socio-economic benefits by diversifying income streams, reducing food expenses, and empowering women and youth through their involvement in establishment and maintenance. They enhance food security by providing diverse, nutritious crops locally and serve as social hubs for education on food production and healthy soils, positively impacting mental health. Ecologically, they promote biodiversity, improve soil health through organic practices, and conserve water resources through efficient irrigation systems. In summary, Kitchen Gardens contribute to increased household income, reduced food expenses, improved dietary diversity, and enhanced ecological sustainability, making them valuable assets for communities.

Silvopasture

Similar names: silvopastoral system, mixed pastures.

Silvopasture is a technique that integrates trees and shrubs with the keeping of grazing livestock on the same piece of land. Silvopasture interventions aim to realise the benefits of combining two systems: grazing animals help to keep weeds away from trees and fertilise the soil with manure, while trees (often fruit trees) provide additional fodder for the livestock through their extra leaves/biomass. Silvopastoral systems are used as an alternative to conventional cattle farming systems to combat deforestation problems.

This intervention is traditionally applied in tropical and temperate zones but also in subhumid, semiarid, and arid regions. Some other variations are agro-silver-pastures, which combine trees or shrubs, wish crops and cattle. A more complex system should be well planned but that can bring a variety of benefits. Also called the crop-livestock-forest system (CIF). Another alternative is silver fishery, which combines woody perennials and fish resources.

Silvopasture offers numerous ecological benefits, including improved water management by reducing runoff and increasing retention, which prevents soil erosion and landslides. It enhances soil quality and nutrient content, supports carbon sequestration through tree planting, and boosts biodiversity by introducing trees that provide habitats for various species. Additionally, it reduces the risk of fire by controlling understory vegetation and improves livestock conditions by providing shade, which can increase their lifespan and milk yield. Economically, silvopasture lowers costs by using livestock for weed control, diversifies income sources through harvesting trees and livestock products, and enhances food security and sustainability for farming communities. It also supports indigenous livelihoods by preserving traditional knowledge and culture.

Charco Dams

Charco Dams are a traditional means of water harvesting in arid and semi-arid landscapes of Eastern Africa, especially in Tanzania. This type of dam has a deep reservoir and limited surface area which helps to reduce water-loss from evaporation. Charco Dams are built to collect rainwater and runoff water from flat surfaces. As a result, they are suitable for livestock watering and crop irrigation, but less suitable for domestic use (unless the water is treated). Typically, trees and shrubs are planted around the edges of the dam to act as windbreaks to further reduce evaporation. Small earth dams may vary significantly in size based on the water storage capacity needed. Storage of up to 1000m3 is possible, beyond which a pond is considered large and will require different building protocols. Dams need to be thoroughly planned in order to ensure their feasibility, longevity, and safety. Please make sure to consult the additional supporting resources provided for more specific details on how to plan and build a Charco Dam, or talk to a local extension officer for help on planning and implementing a Charco Dam in your landscape.

Picture by: Rikolto (Vredeseilanden)