Classification of the Severnaya Dvina River and the Vychegda River Channel Sections According to Complexity of Channel Processes and their Management Conditions

The complexity of the control conditions for channel processes is examined by the case of the Severnaya Dvina River and its main tributary the Vychegda River, which are both the most important waterways of the European North of Russia. The developed and approved earlier methodology was applied to rank rivers in by the channel stability, the load and composition of sediments (the factor was applied for the first time to the rivers under study), water capacity, geological and geomorphological conditions of the channel formation conditions (embedded riverbeds or channels with wide floodplain), evolution of different morpho/dynamic types of channel, abundance and mode of deformations of riffles. The latter factor controls both possibility and features of regulative works when designing activities in water economics, navigation and construction. The data on the sediment amounts dredged from riverbeds to ensure the waterway functioning are demonstrated to be the integral estimation of the control conditions for channel processes.

Precipitation seasonality promotes acquisitive and variable leaf water-economics traits in southwest Australian granite outcrop species

Southwestern Australia (SWA) is a global biodiversity hotspot characterized by a mediterranean climate and is among the world’s oldest and resource-poorest landscapes. Within this region, granite outcrops provide habitat complexity, and contribute to high levels of species diversity and endemism. Granite outcrop plant species are characterized by distinct anatomical, morphological and eco-physiological traits. So far, functional studies of SWA granite outcrop plants examined trait patterns along the stark aridity gradient that occurs in the region. Despite precipitation seasonality being an important climatic driver of plant species richness and distribution in mediterranean-type ecosystems, relationships between plant traits and precipitation seasonality remain understudied. Here, we investigated granite outcrop species’ responses to changes in precipitation seasonality in terms of average and variability values of leaf traits related to water use efficiency. We found that plants displayed more acquisitive and variable trait values with increasing precipitation seasonality. These patterns are likely associated with the long-term effect of the stable and predictable precipitation regime in the old SWA that may have fine-tuned plant water use strategies to maximize water acquisition during the most favourable season.