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Blackbrush (Coleogyne ramosissima Torr.) is the dominant shrub on three million hectares across the transition zone between the western North American warm and cold deserts. This paper presents a study of blackbrush population structure at the stand level at sixteen sites across the species range. New stand-level information is then integrated with what is already known about blackbrush population ecology to explore the stand-level consequences of several unusual features of blackbrush life history, including its masting reproductive strategy, its interactions with heteromyid rodents that are both seed predators and dispersers, and its ability to form 'seedling banks' of growth-suppressed individuals, often within the crowns of adult conspecifics. It complements earlier work showing that blackbrush stands are organized at both the inter-clump and intra-clump levels. Each clump represents an establishment nexus where younger individual genets replace older genets over an extended time period. Inter-clump structure is thus determined by the rate of establishment of new clumps rather than new individuals. This has resulted in contrasting stand structures in response to rodent community composition, disturbance regimes, and climatic variability at the leading and trailing edges of current blackbrush distribution in the eastern Mojave Desert and Colorado Plateau regions. Because blackbrush likely disperses too slowly to track anthropogenic climate change, assisted migration with wild-collected seeds may be necessary to promote its continued survival and dominance. [ABSTRACT FROM AUTHOR]

Decapod crustaceans are ecologically and commercially important members of marine communities. Faunal surveys constitute essential tools for the understanding of local diversity, especially in areas subjected to significant alterations of community composition due to climate changes, anthropogenic impacts, and biological invasions. Following a literature review and the study of new samples, we hereby update on the Crustacea Decapoda from the Rhodes Island area (Greece), situated in a key position in the eastern Mediterranean Sea. Published data yielded records of 120 species, whereas 28 taxa are recorded here for the first time from the study area. Among them, the collection of Liocarcinus bolivari widens its distribution to the eastern Mediterranean. Details on material examined and distributional/faunal remarks are provided for the species newly recorded and for some other native and alien species rarely reported from Rhodes. The present paper raises the local decapod biodiversity to 148 species, accounting for ~50% of the Hellenic Aegean decapod fauna and provides a useful baseline for analysing the long-term changes in the local fauna and the westward spreading of Lessepsian species. Despite present advances, the lack of records of many common Mediterranean species may be still due to limited fieldwork in some habitats rather than a true absence. [ABSTRACT FROM AUTHOR]

Many corals and reef-dwelling organisms are susceptible to the impacts of storm events, which are typically characterized by large inputs of freshwater, sediment, and nutrients. The majority of storm effects are focused on shallow, nearshore reef flats, as low salinity and sedimentation tend to dissipate with depth and distance from shore. In April 2018, record rainfall on the northern coast of Kaua'i caused extensive flooding and landslides, introducing large amounts of freshwater and sediment into nearshore reefs. Using benthic and fish transects from 2016–2019 and temperature, sediment, and rainfall data gathered pre- and post-flood, this study aimed to quantify and explicate the effects of flooding on the various biotic populations of two reef habitats at Pila'a and Hā'ena, Kaua'i. Results from the shallow Pila'a reef suggest sediment and freshwater-associated declines in mean urchin abundance (−52.0%) and increases in mean coral bleaching (+54.5%) at the flood-prone eastern sector. Additionally, decreases in mean urchin (−65.7%) and fish (−42.3%) populations were observed at shallow Hā'ena transects, but not deep sites, supporting the occurrence of depth-specific affliction. Multivariate community-level analyses affirmed much of these results, showing a significant shift in community structure before and after the flood at both Pila'a and Hā'ena. The outcomes of this study are pertinent to strategic design and solution development by local aquatic resource managers, especially as anthropogenic climate change continues to increase the frequency, duration, and intensity of storm events. [ABSTRACT FROM AUTHOR]

Effective management of coral reefs requires strategies tailored to cope with cumulative disturbances from human activities. In Brazil, where coral reefs are a priority for conservation, intensifying threats from local and global stressors are of paramount concern to management agencies. Using a cumulative impact assessment approach, our goal was to inform management actions for coral reefs in Brazil by assessing their exposure to multiple stressors (fishing, land-based activities, coastal development, mining, aquaculture, shipping, and global warming). We calculated an index of the risk to cumulative impacts: (i) assuming uniform sensitivity of coral reefs to stressors; and (ii) using impact weights to reflect varying tolerance levels of coral reefs to each stressor. We also predicted the index in both the presence and absence of global warming. We found that 16% and 37% of coral reefs had high to very high risk of cumulative impacts, without and with information on sensitivity respectively, and 42% of reefs had low risk to cumulative impacts from both local and global stressors. Our outputs are the first comprehensive spatial dataset of cumulative impact on coral reefs in Brazil, and show that areas requiring attention mostly corresponded to those closer to population centres. We demonstrate how the relationships between risks from local and global stressors can be used to derive strategic management actions. [ABSTRACT FROM AUTHOR]