Interacciones efectivas entre academia y gestión: participación de voluntarios para el control de una hiedra invasora en Puerto Blest, Parque Nacional Nahuel Huapi (Argentina)

Introducción y objetivos: Las prácticas de manejo de especies no-nativas e invasoras es tema prioritario en áreas protegidas, en especial en estadios tempranos de invasión, porque facilita la recuperación de sistemas nativos. Aquí presentamos una metodología para el control de una planta trepadora invasora, Hedera helix (Araliaceae).  M&M: Se realizó remoción manual y la disposición de los residuos se compostó en bolsas en el lugar. Luego se monitoreó la regeneración natural del bosque nativo. La propuesta incluye la convocatoria de voluntarios, enmarcados en un proyecto de investigación y extensión de la Universidad Nacional Comahue Bariloche con la colaboración de la Administración de Parques Nacionales.  Resultados: Desde 2019 participaron 47 voluntarios, se extrajeron 870 kg (peso húmedo) de material de cinco de los seis sitios identificados. Dos de los cinco sitios intervenidos se encuentran en la etapa de monitoreo de especies nativas.  Conclusión: La participación de voluntarios resultó efectiva en términos de las acciones de control manual, al estar los sitios controlados. De esta manera, se está logrando con éxito un mínimo impacto negativo sobre el entorno, al menos en las especies de plantas, evidenciado por una rápida recolonización pasiva de especies nativas y la eliminación la especie invasora en los sitios intervenidos. En particular, este modo de trabajo permite crear conciencia del problema de las invasiones biológicas en la comunidad y en futuros profesionales. También fortalece las relaciones entre instituciones vinculando la academia con la gestión en conservación, un aspecto a veces difícil de lograr. 

Opposing community assembly patterns for dominant and nondominant plant species in herbaceous ecosystems globally

Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead may ameliorate environmental stressors that usually limit nondominants. Hence, the nature of interactions among nondominant species could be modified by dominant species. Furthermore, these differences could translate into a disparity in the phylogenetic relatedness among dominants compared to the relatedness among nondominants. By estimating phylogenetic dispersion in 78 grasslands across five continents, we found that dominant species were clustered (e.g., co-dominant grasses), suggesting dominant species are likely organized by environmental filtering, and that nondominant species were either randomly assembled or overdispersed. Traits showed similar trends for those sites (<50%) with sufficient trait data. Furthermore, several lineages scattered in the phylogeny had more nondominant species than expected at random, suggesting that traits common in nondominants are phylogenetically conserved and have evolved multiple times. We also explored environmental drivers of the dominant/nondominant disparity. We found different assembly patterns for dominants and nondominants, consistent with asymmetries in assembly mechanisms. Among the different postulated mechanisms, our results suggest two complementary hypotheses seldom explored: (1) Nondominant species include lineages adapted to thrive in the environment generated by dominant species. (2) Even when dominant species reduce resources to nondominant ones, dominant species could have a stronger positive effect on some nondominants by ameliorating environmental stressors affecting them, than by depleting resources and increasing the environmental stress to those nondominants. These results show that the dominant/nondominant asymmetry has ecological and evolutionary consequences fundamental to understand plant communities.

Minimizing fear of wildlife in urban areas

[Figure: see text].

Global Aerial Habitat Conservation Post-COVID-19 Anthropause

Aerial habitat is increasingly threatened. The coronavirus disease 2019 (COVID-19) anthropause shows that a decrease in human mobility and goods production for even a short period reduces the global anthropogenic impact on airspace fragmentation and pollution. Economic and environmental post-COVID-19 agendas should consider the changes observed in the aerial habitat during the anthropause.