Responses of fisheries ecosystems to marine heatwaves and other extreme events

Marine ecosystems and their living marine resources (LMRs) continue to respond to the effects of global change, with environmental factors impacting marine fisheries biomass, distribution, harvest, and associated economic performance. Extreme events such as high-category hurricanes, harmful algal blooms, marine heatwaves, and large-scale hypoxia affect major regions and subregions of United States waters, with their frequency expected to increase over the next decades. The impacts of extreme events on fisheries biomass, harvest, and economic performance have not been examined as closely as a system (i.e., cumulatively), or in terms of their differential effects on particular functional groups of a given system. Among several U.S. subregions, we examined responses of fisheries biomass, landings, and revenue for particular functional groups to large-scale environmental perturbations (i.e., marine heatwaves, Hurricane Katrina, Deepwater Horizon oil spill). Distinct negative short-term consequences to annual fisheries biomass, landings, and revenue were observed in all regions, including at the system-level scale for several ecosystems which have higher proportions of pelagic species composition and variable shellfish-based revenue. In addition, shifts in species composition often were associated with environmental perturbations. Recovery to pre-perturbation levels (both in the immediate years following the event and over the post-event period of study) and resilience at the system level was observed in several cases, although post-event declines in biomass and landings occurred in the California ecosystem. Certain extreme events are expected to become more common in marine environments, with resulting perturbations throughout multiple components of U.S. socioecological systems. The recognition and understanding of the consequences of extreme events throughout marine ecosystems is necessary for effective, holistic, and sustainable management practices.

Revitalizing contaminated lands: A state-of-the-art review on the remediation of mine-tailings using phytoremediation and genomic approaches

The mining industry has historically served as a critical reservoir of essential raw materials driving global economic progress. Nevertheless, the consequential by-product known as mine tailings has consistently produced a substantial footprint of environmental contamination. With annual discharges of mine tailings surpassing 10 billion tons globally, the need for effective remediation strategies is more pressing than ever as traditional physical and chemical remediation techniques are hindered by their high costs and limited efficacy. Phytoremediation utilizing plants for remediation of polluted soil has developed as a promising and eco-friendly approach to addressing mine tailings contamination. Furthermore, sequencing of genomic DNA and transcribed RNA extracted from mine tailings presents a pivotal opportunity to provide critical supporting insights for activities directed towards the reconstruction of ecosystem functions on contaminated lands. This review explores the growing prominence of phytoremediation and metagenomics as an ecologically sustainable techniques for rehabilitating mine-tailings. The present study envisages that plant species such as Solidago chilensis, Festuca arundinacea, Lolium perenne, Polygonum capitatum, Pennisetum purpureum, Maireana brevifolia, Prosopis tamarugo etc. could be utilized for the remediation of mine-tailings. Furthermore, a critical evaluation of the organic and inorganic ammendments that optimize conditions for the remediation of mine tailings is also provided. The focus of this review extends to the exploration of environmental genomics to characterize microbial communities in mining sites. By delving into the multifaceted dimensions of phytoremediation and genomics for mine tailings, this study contributes to the ongoing efforts to revitalize contaminated lands for a sustainable and environmentally friendly future.

Key determinants controlling the seasonal variation of coastal zooplankton communities: A case study along the Yellow Sea

Zooplankton play key top-down and bottom-up regulatory roles in aquatic food webs, and are also ecologically indicative in marine ecosystems. However, there are relatively limited data on the effects of environmental changes on natural zooplankton communities, especially in coastal ecosystems. In the present study, we systematically evaluated the potential effects of various environmental variables, such as temperature, salinity, and nutrients, on the zooplankton communities along the coastal Yellow Sea during spring, summer, and fall. The results showed that the average abundance of zooplankton decreased in general from spring to autumn, but the biomass exhibited a different seasonal variation trend, with the highest in summer and the lowest in fall. Throughout the three seasons, copepods were the most dominant species within the zooplankton communities, followed by Pelagic larvae and Hydromedusae. However, Noctiluca miliaris accounted for a large proportion of zooplankton abundance during spring. Moreover, the correlation analysis was applied to explore the potential effects of environmental factors on the seasonal variation of zooplankton communities. The results showed that chlorophyll a (Chl a) and salinity were significantly correlated with zooplankton abundance and biomass during spring. The implication is that high phytoplankton biomass (expressed as Chl a) and salinity would benefit the growth of zooplankton in spring. During summer and fall, the effects of dissolved inorganic phosphate (DIP) on the zooplankton abundance and biomass showed a significant positive correlation, indicating that zooplankton were better able to tolerate high DIP during summer and fall. Taken together, Chl a, salinity, and DIP may be the key determinants controlling the seasonal dynamics of zooplankton communities in the coastal Yellow Sea.

Long-Term Ecological Research on Ecosystem Responses to Climate Change

In this article marking the 40th anniversary of the US National Science Foundation's Long Term Ecological Research (LTER) Network, we describe how a long-term ecological research perspective facilitates insights into an ecosystem's response to climate change. At all 28 LTER sites, from the Arctic to Antarctica, air temperature and moisture variability have increased since 1930, with increased disturbance frequency and severity and unprecedented disturbance types. LTER research documents the responses to these changes, including altered primary production, enhanced cycling of organic and inorganic matter, and changes in populations and communities. Although some responses are shared among diverse ecosystems, most are unique, involving region-specific drivers of change, interactions among multiple climate change drivers, and interactions with other human activities. Ecosystem responses to climate change are just beginning to emerge, and as climate change accelerates, long-term ecological research is crucial to understand, mitigate, and adapt to ecosystem responses to climate change.