Biology subjects

Muys, B.

Publications and source records attributed to Muys, B..

8 recordsLinked to original sources

bioRxiv2026

Effects of Mango Maize and Mango Cassava Agroforestry Systems on Arbuscular Mycorrhizal Fungi Communities and Soil Properties in Southern Ethiopia

Subsistence agriculture in sub-Saharan Africa faces persistent productivity challenges due to low soil fertility, limited inputs, and increasing climate variability. Agroforestry can offer a sustainable strategy for smallholder systems by enhancing soil quality and the presence of arbuscular mycorrhizal fungi (AMF) in crop roots. Using a canopy-based radial sampling design, we assessed the influence of Mangifera indica (mango) trees on soil properties and AMF communities in maize and cassava in southern Ethiopia. Illumina MiSeq sequencing identified 908 AMF operational taxonomic units (OTUs) from 7 families, dominated by Glomeraceae. While soil properties, including pH, total nitrogen (TN), organic carbon, and potassium, were significantly affected by the distance from mango trunks, this was not the case for AMF community composition and AMF richness and diversity. Host identity, rather than distance from the mango trees, was the primary driver of AMF community composition, with distinct and host-specific assemblages in mango, maize, and cassava roots. Soil nutrients influenced AMF diversity differently across hosts. In maize-mango systems, TN positively affected observed richness (Sobs) and Shannon diversity (N1), whereas Olsen P negatively affected N1 and Simpson diversity (N2). In cassava-mango systems, TN enhanced Sobs, and Olsen P positively influenced expected richness (Sexp). Overall, these findings demonstrate a decoupling between mango-induced soil fertility enhancement and crop AMF community composition and diversity, rather emphasizing the roles of host type and soil nutrients in structuring AMF communities. Without demonstrating direct benefits, we at least show that mango can be effectively integrated into smallholder maize and cassava production without compromising the AMF communities, while enhancing key soil fertility indicators. Maintaining adequate nitrogen levels while avoiding excessive phosphorus inputs may help sustain stable AMF communities in agroforestry systems.

ecology↗

bioRxiv2026

Effects of agroforestry trees on microclimate and enset (Ensete ventricosum) morphophysiology in South Ethiopia

Enset (Ensete ventricosum), a multipurpose crop domesticated exclusively in Ethiopia, serves as a staple food for millions of smallholder farmers. It is primarily cultivated as a monocrop in homegardens, leaving it vulnerable to climate change risks. One potential nature-based solution involves agroforestry systems; however, ensets response to canopy cover remains unclear. This study examined how scattered trees in enset farms affected microclimate and enset morpho-physiology in South Ethiopia. Trees significantly modified the microclimate conditions in enset homegardens. The average daily reductions in air, soil surface, and soil temperatures ranged from -0.5 to -1.9 {degrees}C, -0.4 to -2.1 {degrees}C, and +0.4 to -1.0 {degrees}C, respectively. The minimum soil moisture offset ranged from +0.8% to +5.7%. Although the tree identity effect on enset growth was negligible, planting position relative to the overstory trees significantly influenced enset responses. Most morphophysiological traits were higher under tree canopies, with progressively lower values at the edge and outside the tree canopy. In contrast, leaf dry matter content exhibited an inverse trend, aligning with the leaf economics spectrum. These results demonstrate ensets adaptability to canopy shade, suggesting potential for agroforestry expansion. Cultivar-specific shade tolerance and ideal shade levels to maintain enset productivity should be investigated further.

plant biology↗

bioRxiv2026

Loss of competitive strength in European conifer species under climate change

Climate change is expected to alter species assemblages by affecting the outcome of competition between species. Investigating processes of competition remains challenging particularly in tree communities, as they unfold over extensive spatio-temporal scales. Here, we developed a deep-learning approach to leverage a novel database of 135 million simulated local-scale tree responses to climate across continental Europe to investigate changes in the competitiveness of nine major tree species under different scenarios of climate change. Specifically, we trained a Deep Neural Network on local process model projections to investigate climate change effects on indicators of competitive strength and species dominance. We found decreasing competitive strength for all investigated evergreen coniferous species across their distribution, while major deciduous broadleaved species such as Quercus robur and Fagus sylvatica increased in competitiveness. Changes in tree species competition with climate differed locally, but most investigated species lost competitive strength at their warm range edges. As a consequence of these changes, up to 19% of Europes forests could experience a change in the dominant tree species until the end of the 21st century. Our results suggest a profound climate-induced reassembly of Europes forests and identify areas that may require specific attention in forest policy and management.

ecology↗

bioRxiv2025

Trait-environment interactions influence tree planting success in Peruvian tropical dry forests

Tropical dry forests (TDFs) are among the most endangered ecosystems globally, despite their critical socio-ecological importance. In recent decades, tree-planting initiatives have been widely implemented to restore these forests, yielding mixed results. To enhance restoration effectiveness, it is imperative to adopt a predictive approach, focusing on the drivers of seedling performance and their interactions. This study explores how functional traits of planted tree species interact with site environmental conditions to influence seedling survival and growth rates across nine restoration sites of varying ages and climatic conditions within the Peruvian Tumbes-Piura TDFs. While the widely accepted resource-use theory predicts that acquisitive species - focusing on the fast retrieval of resources and characterised by higher specific leaf area and lower wood density - achieve high growth rates in resource-rich environments but experience sharp declines under resource-limited conditions, we found that acquisitive species maintained their high growth rates along the environmental gradient. In contrast, conservative species, expected to be less sensitive to resource variability, exhibited marked declines in growth when water or nutrient availability decreased. Additionally, nitrogen-fixing species did not outperform non-fixers in growth or survival, indicating that nitrogen fixation alone does not confer a consistent advantage in early restoration. Overall, our findings highlight the importance of trait-environment interactions in tree planting performance and underscore the need to align species selection and management strategies with site conditions and broader restoration goals to enhance the success of TDF restoration. Implications for practice- Our findings highlight the importance of considering trait-environment interactions when evaluating growth rates across TDF restoration sites. - Planting acquisitive species, which maintained higher growth rates than conservative species even under resource-poor environmental conditions, can accelerate tropical dry forest recovery in resource-poor restoration sites within the Peruvian Tumbes-Piura region. - While seedling growth is strongly shaped by environmental factors and their interaction with functional traits, survival may depend more on site-specific factors and management interventions, including irrigation and fertilisation. - Selecting species based solely on nitrogen fixation ability may not enhance restoration success, as nitrogen-fixing species did not exhibit higher growth or survival than non-fixers.

ecology↗

bioRxiv2025

Resource economics of tree communities control soil food web multifunctionality in European forests

Plants affect terrestrial ecosystem functioning by performing the primary production that energetically sustains heterotrophic organisms1, and by shaping the microenvironment2. However, the influence of plant diversity and community composition on ecosystem functioning through their effects on energy flow into food webs has been little studied3,4, especially for soil food webs that channel most of the plant-derived energy1,5. Applying a food web energetics approach6,7, we show that the resource economics of dominant tree species control soil food web multifunctionality across European forests. Specifically, tree communities dominated by resource acquisitive species promoted faster rates of multiple soil trophic functions simultaneously than did those dominated by resource conservative species. This was primarily driven by their production of plant litter with higher nutritional quality and their warmer forest microclimate, leading to a higher metabolic activity of soil organisms8. Tree species mixing had rather weak and negative effects on soil food web multifunctionality, mostly due to a shift in the resource-based energy channeling from living plant fine roots to litter and a cooling effect on the forest microclimate. Tree diversity effects were largely outweighed by community compositional effects, which were of similar magnitude to the effects of biogeographic differences among locations. Our findings emphasize the importance of plant functional traits related to resource economics as drivers of plant community effects on soil food web functioning5,9 and highlight the consequences that climate-driven shifts in tree community composition could have for forest soil functioning.

ecology↗

bioRxiv2024

Incorporating climatic extremes using the GEV distribution improves SDM range edge performance

AimThe changing frequency and intensity of climatic extremes due to climate change can have sudden and adverse impacts on the distribution of species. While species distribution modelling is a vital tool in ecological applications, current approaches fail to fully capture the distribution of climatic extremes, particularly of rare events with the most disruptive potential. Especially at the edges of species ranges, where conditions are already less favourable, predictions might be inaccurate when these extremes are not well represented. LocationEurope TaxonTree species MethodsWe present a novel approach to integrate extreme events into species distribution models based on the generalised extreme value (GEV) distribution. This distribution, following from the extreme value theory has been established as a valuable tool in analysing climatic extremes, both in an ecological context and beyond. The approach relying on the GEV distribution is broadly applicable, readily transferable across species and relies on widely available data. We demonstrate the efficacy of our approach for 28 European tree species, illustrating its superior ability to fully capture the distribution of climatic extremes compared to state-of-the-art methods. ResultsWe found that incorporating parameters on climatic extremes derived from the GEV distribution increased model performance (AICmodel) and characterized range edges more accurately (AUCedge) compared to competing approaches. However, general AUC values were only marginally increased across the species and study period analysed. Overall, the GEV model predicted a narrower niche for the species included in this study. Main conclusionsIncorporating climatic extremes can impact spatial predictions of species distribution models, especially at range margins. We found that using the GEV distribution to characterise extreme variables in SDMs yields the best performance at these distribution edges. Given the importance of range edges for species conservation, a detailed inclusion of extremes in SDMs employed for those applications will help ensure robust conclusions.

ecology↗

bioRxiv2021

Trick or Treat? Pollinator attraction in Vanilla pompona (Orchidaceae)

Natural pollination of species belonging to the pantropical orchid genus Vanilla remains poorly understood. Based on sporadic records, euglossine bees have been observed visiting flowers of Neotropical Vanilla species. Our research aimed at better understanding the pollinator attraction mechanism of the Neotropical species Vanilla pompona, a crop wild relative with valuable traits for vanilla crop improvement programs. Using video footage, we identified floral visitors and examined their behavior. The flowers of V. pompona attracted Eulaema cingulata males, which distinctively displayed two behaviors: floral scent collection and nectar search; with the latter leading to pollen removal. Morphological measurements of floral and visitor traits showed that other Eulaema species may also act as potential pollinators. Additionally, we recorded natural fruit set in three populations and over a period of two years, tested for nectar presence and analyzed floral fragrances through gas chromatography - mass spectrometry. We observed a low natural fruit set (2.42%) and did not detect nectar. Twenty floral volatile compounds were identified, with the dominant compound trans-carvone oxide previously found to attract Eulaema cingulata males. We hypothesize a dual attraction of Eulaema cingulata males to V. pompona flowers, based on floral fragrance reward as the primary long-distance attraction, and food deception for successful pollen removal. Further research confirming this hypothesis is recommended to develop appropriate conservation policies for Vanilla crop wild relatives, which are the primary reserves of this crops genetic variation.

plant biology↗

bioRxiv2020

Biotic and abiotic drivers of soil microbial functions across tree diversity experiments

AimSoil microorganisms are essential for the functioning of terrestrial ecosystems. Although soil microbial communities and functions may be linked to the tree species composition and diversity of forests, there has been no comprehensive study of how general potential relationships are and if these are context-dependent. A global network of tree diversity experiments (TreeDivNet) allows for a first examination of tree diversity-soil microbial function relationships across environmental gradients. LocationGlobal Major Taxa StudiedSoil microorganisms MethodsSoil samples collected from eleven tree diversity experiments in four biomes across four continents were used to measure soil basal respiration, microbial biomass, and carbon use efficiency using the substrate-induced respiration method. All samples were measured using the same analytical device in the same laboratory to prevent measurement bias. We used linear mixed-effects models to examine the effects of tree species diversity, environmental conditions, and their interactions on soil microbial functions. ResultsAcross biodiversity experiments, abiotic drivers, mainly soil water content, significantly increased soil microbial functions. Potential evapotranspiration (PET) increased, whereas soil C-to-N ratio (CN) decreased soil microbial functions under dry soil conditions, but high soil water content reduced the importance of other abiotic drivers. Tree species richness and phylogenetic diversity had overall similar, but weak and context-dependent (climate, soil abiotic variables) effects on soil microbial respiration. Positive tree diversity effects on soil microbial respiration were most pronounced at low PET, low soil CN, and high tree density. Soil microbial functions increased with the age of the experiment. Main conclusionsOur results point at the importance of soil water content for maintaining high levels of soil microbial functions and modulating effects of other environmental drivers. Moreover, overall tree diversity effects on soil microbial functions seem to be negligible in the short term (experiments were 1-18 years old). However, context-dependent tree diversity effects (climate, soil abiotic variables) have greater importance at high tree density, and significant effects of experimental age call for longer-term studies. Such systematic insights are key to better integrate soil carbon dynamics into the management of afforestation projects across environmental contexts, as todays reforestation efforts remain focused largely on aboveground carbon storage and are still dominated by less diverse forests stands of commercial species.

ecology↗