Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

A ECOLOGIA DE PEIXES DE RIACHO SOB A PERSPECTIVA DA ECOLOGIA DE PAISAGENS

Landscape ecology emphasizes the interaction between spatial patterns and ecological processes, i.e., the consequences of spatial heterogeneity across various scales. It is an interdisciplinary science that seeks to understand the relationships between ecological patterns and processes considering different spatial and temporal scales. This understanding has been supported by the rapid development of a methodological framework, largely based on Geographic Information Systems (GIS). Thus, it has allowed understanding how ecological processes are affected by anthropogenic activities that trigger profound changes in ecosystems, such as habitat loss and fragmentation. Although commonly applied to studies in terrestrial ecosystems, there is a time lag in both theoretical development and methodological adaptation of landscape ecology applied to studies in streams, especially in Brazil. Methodological adaptations are necessary considering the particularities of aquatic environments in relation to terrestrial ones. For example, streams have a hierarchical spatial organization that results in local conditions dependent on the regional context. In fact, streams are connected to the landscape in which they are inserted through multiple spatial and temporal scales. This hydrologic connectivity, and the low ratio/proportion of aquatic/terrestrial areas, in turn results in anthropogenic impacts accumulating along the hydrographic networks. Considering the above, the objectives of this chapter are: (1) Introduce the general concepts of landscape ecology; (2) Present the main methods of spatial data acquisition and management relevant to stream approaches; (3) Describe the spatial and temporal scales relevant to stream ecology and (4) Discuss the potential of landscape ecology to assess human impacts on streams. Landscape ecology has much to offer to the study of stream fish in Brazil and has shown to be a promising approach for advancing this frontier of knowledge.</jats:p