Hylander, K. | Search bioRxiv

bioRxiv2025

Open-land-derived agroforestry and effects of abandonment of management of the main crop on ecosystem services and woody plant diversity

Tropical forests are biodiversity hotspots threatened by deforestation and fragmentation. One strategy to restore tropical forest is to establish agroforestry on open land. However, we lack insights into the social and ecological dynamics of open-land-derived agroforests, and specifically the reasons for and consequences of abandonment. We combined semi-quantitative interviews with biodiversity surveys to examine the reasons for abandonment and the consequences for ecosystem services, disservices, and the woody plant community in the Atlantic Forest region. Reasons for abandonment were primarily related to agroecology. Ecosystem services, disservices, and woody plant diversity had not (yet) differentiated after the abandonment of management. Strengthening agronomic support to farmers is essential to maintain and expand open-land-derived agroforestry. Notably, as abandoned agroforests were not converted back to open land, partly due to legal restrictions, they continued to provide ecosystem services and contributed to the restoration of native tree cover across the landscape.

ecology↗

bioRxiv2020

Drivers of large-scale spatial demographic variation in a perennial plant

To understand how the environment drives spatial variation in population dynamics, we need to assess the effects of a large number of potential drivers on the vital rates (survival, growth and reproduction), and explore these relationships over large geographical areas and long environmental gradients. In this study, we examined the effects of a broad variety of abiotic and biotic environmental factors, including intraspecific density, on the demography of the forest understory herb Actaea spicata between 2017 and 2019 at 40 sites across Sweden, including the northern range margin of its distribution. We assessed the effect of potential environmental drivers on vital rates using generalized linear mixed models (GLMMs), and then quantified the impact of each important driver on population growth rate ({lambda}) using integral projection models (IPMs). Population dynamics of A. spicata were mostly driven by environmental factors affecting survival and growth, such as air humidity, soil depth and forest tree species composition, and thus those drivers jointly determined the realized niche of the species. Soil pH had a strong effect on the flowering probability, while the effect on population growth rate was relatively small. In addition to identifying specific drivers for A. spicatas population dynamics, our study illustrates the impact that spatial variation in environmental conditions can have on {lambda}. Assessing the effects of a broad range of potential drivers, as done in this study, is important not only to quantify the relative importance of different drivers for population dynamics but also to understand species distributions and abundance patterns.

plant biology↗