Spore diversity of arbuscular mycorrhizal fungi in human‐modified neotropical ecosystems

Abstract

Neotropical landscapes are diverse mosaics of ecosystems commonly resulting from different degrees of human intervention. Although easily recognized by their vegetation, the associated soil microbiota including arbuscular mycorrhizal fungi (AMF) is little known. In Mexico, native tropical rainforest and native savannas are rapidly vanishing, remaining in few spots surrounded by human‐made ecosystems. It is unknown, however, how such vegetation types differ in their AMF communities. We compared the spore diversity, spore density and root colonization by AMF in contiguous mosaics of tropical rainforest, savanna and two pine plantations, one managed and the other unmanaged. We detected indicator species associated with tropical rainforest. The savanna displayed the highest values of root colonization of AMF and the lowest spore density. Conversely, the highest spore density and the lowest root colonization rates were found in the tropical rainforest. The two pine plantations showed intermediate values of spore density and colonization between tropical rainforest and the savanna. We did not detect significant seasonal differences (between dry and rainy seasons) in AMF species richness, spore density and root colonization within the vegetation types (except for root colonization in the savanna). Soil cation exchange capacity, phosphorus and nitrogen were negatively associated with AMF spore density and species richness. Our findings suggest that contiguous vegetation types in neotropical landscapes may display significant differences in AMF species composition, spore density and root colonization, and that such differences can be explained in part by soil properties and levels of human intervention.

Seasonal variation of arbuscular mycorrhizal fungi in ecotone forests of the northern region of Brazilian Amazonia

“…Of the three forest types studied at Maracá, only in the PRF forest type were there unique indicator species (Giga1 and A. Scro) both in the dry and rainy seasons, and these species may positively influence the monodominance of P. gracilipes in this area. We were able to detect other AMF species that were characteristic of a combination of the forest types under study, in contrast to a study of AMF spore diversity in neotropical ecosystems in Mexico by Álvarez-Lopeztello et al (2019), which did not detect an exclusive AMF indicator species of a habitat type. However, the presence of indicator species of a particular habitat type, such as species that are colonizing the PRF, provides an additional reason to preserve this type of vegetation and to try to understand its function.…”

“…The numbers of AMF spores found here were high (60 to 150 in the dry season and between 25 and 70 in the rainy season) compared to a study conducted by Stürmer et al (2018) in a transition area between savannas -forests, conducted in Roraima, where they recorded between 5 and 25 spores of AMF per 100 g of soil. Some soil properties, such as organic carbon and soil pH, are parameters known to drive AMF diversity on a global scale (Davison et al, 2015), and although AMF species as a group tend to be selective for a particular habitat type (Álvarez-Lopeztello et al, 2019), the RDA analysis showing the relationship between soil properties and the distribution of AMF species on Maracá Island, conducted in both seasons, allowed us to observe that selectivity seems to be common among most of the studied AMF species. We found few species that could be indicative of a certain forest type.…”

Biophysical and Biocultural Upheavals in Mesoamerica, a Conservation Perspective: Mountains, Maize-Milpa, and Globalization

“…Guevara and Laborde, 2014). This conversion implies significant organic matter losses resulting in greenhouse gas emissions (Aryal et al, 2018), likely altering the species composition of many species groups, including AMF (e.g., Alvarez-Lopeztello et al, 2019). Abandoned pasture lands in Panama, Costa Rica, Nicaragua, and Mexico may regenerate into the original vegetation.…”

Composición de las comunidades de hongos micorrícicos arbusculares en diferentes usos de suelo en el Caldenal, Argentina

“…Los suelos agrícolas manejados con las prácticas convencionales intensivas exhiben una menor diversidad en las comunidades de HMA que los tratados orgánicamente y de forma menos intensiva (Melo et al 2019). Todos estos rasgos sugieren que algunas especies de HMA determinadas morfológicamente se pueden utilizar como especies indicadoras ambientales para diferentes parámetros involucrados en los H����� ������������ ������������ �� �� C������� ₉₇ cambios de uso de la tierra (Moora et al 2014;Bouffaud et al 2016;Álvarez-Lopeztello et al 2019), las condiciones climáticas (Oehl et al 2017) y la elevación (Vieira et al 2019). Incluso, considerando los parámetros ecológicos que influyen en las comunidades, se determinó que los estudios morfológicos pueden tener más poder de resolución que los estudios moleculares (Oehl et al 2017).…”