Ecological outcomes of agroforests and restoration 15 years after planting

Abstract

Large-scale forest restoration relies on approaches that are cost-effective and economically attractive to farmers, and in this context agroforestry systems may be a valuable option. Here, we compared ecological outcomes among (1) 12-15-year-old coffee agroforests established with several native shade trees, (2) 12-15-year-old high-diversity restoration plantations, and (3) reference old-growth forests, within a landscape restoration project in the Pontal do Paranapanema region, in the Atlantic Forest of southeastern Brazil. We compared the aboveground biomass, canopy cover, and abundance, richness, and composition of trees, and the regenerating saplings in the three forest types. In addition, we investigated the landscape drivers of natural regeneration in the restoration plantations and coffee agroforests. Reference forests had a higher abundance of trees and regenerating saplings, but had similar levels of species richness compared to coffee agroforests. High-diversity agroforests and restoration plantations did not differ in tree abundance. However, compared to restoration plantations, agroforests showed higher abundance and species richness of regenerating saplings, a higher proportion of animal-dispersed species, and higher canopy cover. The abundance of regenerating saplings declined with increasing density of coffee plants, thus indicating a potential trade-off between productivity and ecological benefits. High-diversity coffee agroforests provide a cost-effective and ecologically viable alternative to high-diversity native tree plantations for large-scale forest restoration within agricultural landscapes managed by local communities, and should be included as part of the portfolio of reforestation options used to promote the global agenda on forest and landscape restoration.

Land‐use history determines stand structure and tree diversity in vanilla agroforests of northeastern Madagascar

“…This re‐establishment of stand structure and vegetation on historically forested fallow land might also result in a quicker rehabilitation and build‐up of soil nutrient stocks (Klanderud et al, 2010). Furthermore, fallow‐derived agroforests can be integrated as a restoration approach into certification schemes to provide incentives to farmers to maintain or plant trees on historically forested open land (Giudice Badari et al, 2020). Especially since Madagascar is among the countries with highest mean restoration opportunity scores (Brancalion et al, 2019), fallow‐derived vanilla agroforests could be integrated into the national restoration agenda.…”

“…However, agroforestry is multi‐facetted: on the one hand, it may drive further forest conversion, thereby accelerating species loss and stand structure simplification (Rappole et al, 2003). On the other hand, agroforestry may restore tree cover and associated biodiversity, and ecosystem functions and services on historically forested and degraded lands (Martin et al, 2020a) and might therefore provide an attractive restoration practice (Brancalion et al, 2018; Giudice Badari et al, 2020).…”

Forest landscape restoration: state of play

“…Although much of the Bonn Challenge discussion revolves around increasing forest cover by artificial or natural regeneration, many other restoration interventions are available (table 2). Multiple restoration objectives can be met by manipulating vegetation to increase structural complexity, change species composition and restore natural disturbance processes [107][108][109][110]. Livelihoods interventions are very context-specific but generally include alternative practices associated with the forest such as collecting or raising non-timber forest products (e.g.…”

People, primates and predators in the Pontal: from endangered species conservation to forest and landscape restoration in Brazil's Atlantic Forest

“…Further, in this region, agroforestry can be a cost-effective pathway for restoration that provides direct economic benefits for farmers, especially in the early years. Implementation costs for agroforestry and restoration plantations are around USD3000 and USD4800 per hectare, respectively [35].…”

“…This less-intensive and less costly restoration activity generates income for local communities through the capacitation and hiring of local labour to carry out the many activities of assisted natural regeneration, such as controlling invasive grasses and leaf-cutting ants and fencing (figure 6). Natural regeneration sampled in forest restoration planting sites is composed of 50 species, of which 14 were not actively planted [35].…”