Landscape- and Local-Scale Actions Are Essential to Conserve Regional Macrophyte Biodiversity

Abstract

Regional-scale pond diversity is supported by high variation in community composition. To effectively and efficiently conserve pond regional diversity, it is essential to recognize the community types in a focal region and the scales of the factors influencing the occurrence of respective community types. Based on a flora survey and GIS analysis of 367 ponds in western Japan, we developed a multinomial regression model that describes the relationship between aquatic macrophyte community type (based on cluster analysis) and five environmental factors that differ in the spatial scale at which they operate (i.e., landscape or local scale) and origin (i.e., natural or anthropogenic). A change in topographic configuration resulted in a transition of the community types with high species richness. Increasing urban and agricultural area around ponds resulted in a decrease in species-rich community occurrence; an increase in urban area increased the probability of a pond having no macrophytes, whereas that of paddy field increased the probability of a pond having only a few macrophytes. Pond surface area and proportion of artificial embankment significantly defined the pond community: greater embankment proportions increased the probability of ponds having few or no macrophytes. Our results suggest that conserving regional pond biodiversity will require actions not only at a local scale but also at a sufficiently large spatial scale to cover the full gradient of topographic configurations that influence the macrophyte species composition in ponds.

Desafios e Perspectivas na Conservação da Isoëtes cangae

“…O risco para as macrófi tas é particularmente maior em se tratando das espécies endêmicas, as quais podem ter grande parte ou mesmo toda a população existente exposta a ameaças locais, podendo resultar em sua extinção. Assim, é fundamental o desenvolvimento de ferramentas e modelos biológicos que permitam a realização de esforços de manejo efetivos, buscando a conservação das espécies e dos ecossistemas que habitam tanto em escala local quanto em global (Akasaka et al 2018, Stefanidis e Papastergiadou 2019.…”

Geographical variation of aquatic macrophyte biodiversity: Towards an integration of scale and ecological organisation = Variación geográfica en la biodiversidad de los macrófitos acuáticos: hacia una integración de la escala y la organización ecológica

“…More recently, multi-scale approaches, which typically combine local, regional and global scales (Fig. 4a), indicated the need for conservation actions focused on larger spatial scales than individual catchments (Decklerk et al 2006, Akasaka et al 2018. As this thesis suggests, local environmental conditions remain an issue and so regional management continues to have an important role.…”