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Improving the accuracy of aboveground biomass estimations in secondary tropical dry forests

Biomass estimates in tropical forests are mainly available for old-growth forests, but the expansion of tropical secondary forests urges the development of tools for more accurate estimations of biomass and carbon pools. In this study, we developed local allometric models to estimate aboveground biomass in secondary tropical dry forests of the Chamela region in western Mexico and compared their accuracy to that of non-local (“foreign”) allometric models. We harvested 303 trees from 27 woody species contributing ≥75% of total basal area in secondary forest plots (5–45 y-old) distributed across the landscape.

Economic valuation of ecosystem services from secondary tropical forests: trade-offs and implications for policy making

Natural regeneration of secondary forests can be an important source of recovery of ecosystem services (ES) critical for humanity, especially for climate change mitigation and adaptation goals. However, natural regeneration entails synergies and trade-offs across ESs and across stakeholders. To evaluate these trade-offs, we assessed the economic value of four ESs along the course of a natural regeneration process of tropical dry forests of the Pacific Coast of Mexico, and examined how this can inform the design of Payment for Ecosystem Services (PES) schemes incentivizing forest restoration.

Unraveling households’ natural resource management strategies: a case study in Jalisco, Mexico

The analysis of resource management strategies is considered to be relevant to the conservation and sustainable use of ecosystems. In Mexico, ejidos are the most important of the land tenure institutions that grant access to resources inside communities. Although it is recognized that an ejido’s internal structure creates different social groups, few studies have explored their resource management strategies. The aim of this study was to characterize natural resource management strategies in two ejidos in a highly biodiverse region on the southern coast of Jalisco, Mexico.

Assessing the cascading effects of management and landscape on the arthropod guilds occurring in papaya plantations

El manejo intensivo tiene un impacto negativo en la produccion de papaya y sus enemigos naturales.

Susceptibility of Sphenarium purpurascens purpurascens (Orthoptera: Pyrgomorphidae) instars to a commercial strain of Metarhizium acridum (Hypocreales: Clavicipitaceae) in Michoacan, Mexico

El objetivo de este estudio fue evaluar el desempeño de una cepa comercial del hongo entomopatógeno Metarhizium acridum en diferentes estadios del saltamonte plaga Sphenarium purpurascens purpurascens, así como su esporulación a través de bioensayos bajo condiciones de laboratorio, en Michoacán, México. Los estadios más susceptibles fueron las ninfas uno, dos y cuatro, su tiempo de supervivencia promedio fue menor de 6,91 días. El menos susceptible fue el adulto, con un tiempo de supervivencia de 8,36 días.

Resilience of soil aggregation and exocellular enzymatic functions associated with arbuscular mycorrhizal fungal communities along a successional gradient in a tropical dry forest

Arbuscular mycorrhizal (AM) fungi are well-known contributors to soil aggregation and nutrient cycling functions, but we still know little about their capacity to resist or recover from persistent disturbance. Rangeland management may deteriorate these functions by affecting the activity of soil biota, including AM fungi, among other consequences. If affected, some soil properties show recovery when management stops and natural regeneration is allowed. We conducted an experiment to evaluate if the functions related to soil aggregation and promotion of exocellular enzymatic activities associated with AM fungal communities had been affected by rangeland management and, if they had, whether they recovered with successional time when management stopped.

Local-scale spatial diversity patterns of ectomycorrhizal fungal communities in a subtropical pine-oak forest

This study aimed to analyze spatial patterns of soil ectomycorrhizal fungal (EMF) communities at the local scale in a subtropical pine-oak forest located in the Nearctic-Neotropical transition in central Mexico, to underpin biodiversity conservation strategies in forest fragments of this region. We used a spatially-explicit nested square sampling design with the same sampling representativeness at all scales and replicated three times. We detected 674 EMF OTUs within 19,200m2 and 65 OTUs on average per sample.

The spatial analysis of biological interactions: morphological variation responding to the co‐occurrence of competitors and resources

By sharing geographic space, species are forced to interact with one another and the contribution of this process to evolutionary and ecological patterns of individual spe- cies is not fully understood. At the same time, species turnover makes that species composition varies from one area to another, so the analysis of biological interaction cannot be uncoupled from the spatial context. This is particularly important for clades that show high degree of specialization such as hummingbirds, where any variation in biotic pressures might lead to changes in morphology.

Alterations in honey bee gut microorganisms caused by Nosema spp. and pest control methods

Honey bees are associated with gut microorganisms essential for their nutrition and health. The composition of the microbial community can be used as a biological health indicator and is characterized using biomarker fatty acids. Commonly, gut microorganisms are exposed to pathogens and to an array of chemical and biological pest control methods. RESULTS: We found a strong negative effect on microbial gut community composition when exposed to the bee pest control chemicals oxytetracycline, oxalic acid and imidacloprid, and when inoculated with the bee pest Nosema spp.

Plant growth promotion traits of rhizosphere yeasts and their response to soil characteristics and crop cycle in maize agroecosystems

Main results showed that yeasts were present in all maize fields during the complete growing cycle, though highest during flowering. The abundance of rhizosphere yeasts responded negatively to soil pH and amount of Mg.