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1. Continental-scale decrease in net primary productivity in streams due to climate warming

   https://doi.org/10.1038/s41561-018-0125-5  

   Song, Chao; Dodds, Walter K.; Rüegg, Janine; Argerich, Alba; Baker, Christina L.; Bowden, William B.; Douglas, Michael M.; Farrell, Kaitlin J.; Flinn, Michael B.; Garcia, Erica A.; et al (June 2018, Nature Geoscience)
2. Plant community re-organization and increased productivity due to multi-year nutrient enrichment of a coastal grassland

   https://doi.org/10.1371/journal.pone.0270798  

   Brown, Joseph K.; Moulton, Ashley; Zinnert, Julie C. (July 2022, PLOS ONE)

   Kim, Daehyun (Ed.)

   Nutrient enrichment alters plant community structure and function at a global scale. Coastal plant systems are expected to experience increased rates of nitrogen and phosphorus deposition by 2100, caused mostly by anthropogenic activity. Despite high density of studies investigating connections between plant community structure and ecosystem function in response to nutrient addition, inconsistencies in system response based on the ecosystem in question calls for more detailed analyses of nutrient impacts on community organization and resulting productivity response. Here, we focus on nutrient addition impacts on community structure and organization as well as productivity of different lifeforms in a coastal grassland. We established long-term nutrient enrichment plots in 2015 consisting of control (C), nitrogen (N), phosphorus (P), and nitrogen + phosphorus (NP) treatments. In 2017 we collected graminoid and forb productivity, root productivity, and community composition for each plot. We found no N x P interaction, but N enrichment was a significant main effect on productivity, highlighting N limitation in coastal systems. Importantly, nutrient enrichment treatments did not alter root productivity. However, all treatments caused significant differences in community composition. Using rank abundance curves, we determined that community composition differences were driven by increased dominance of nitrophilous graminoids, re-organization of subordinate species, and species absences in N and NP plots. Results of this study highlight how coastal grassland communities are impacted by nutrient enrichment. We show that community re-organization, increased dominance, and absence of critical species are all important mechanisms that reflect community-level impacts of nutrient enrichment in our coastal grassland site. 

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3. Effects of plant diversity on productivity strengthen over time due to trait-dependent shifts in species overyielding

   https://doi.org/10.1038/s41467-024-46355-z  

   Zheng, Liting; Barry, Kathryn E.; Guerrero-Ramírez, Nathaly R.; Craven, Dylan; Reich, Peter B.; Verheyen, Kris; Scherer-Lorenzen, Michael; Eisenhauer, Nico; Barsoum, Nadia; Bauhus, Jürgen; et al (December 2024, Nature Communications)

   Abstract Plant diversity effects on community productivity often increase over time. Whether the strengthening of diversity effects is caused by temporal shifts in species-level overyielding (i.e., higher species-level productivity in diverse communities compared with monocultures) remains unclear. Here, using data from 65 grassland and forest biodiversity experiments, we show that the temporal strength of diversity effects at the community scale is underpinned by temporal changes in the species that yield. These temporal trends of species-level overyielding are shaped by plant ecological strategies, which can be quantitatively delimited by functional traits. In grasslands, the temporal strengthening of biodiversity effects on community productivity was associated with increasing biomass overyielding of resource-conservative species increasing over time, and with overyielding of species characterized by fast resource acquisition either decreasing or increasing. In forests, temporal trends in species overyielding differ when considering above- versus belowground resource acquisition strategies. Overyielding in stem growth decreased for species with high light capture capacity but increased for those with high soil resource acquisition capacity. Our results imply that a diversity of species with different, and potentially complementary, ecological strategies is beneficial for maintaining community productivity over time in both grassland and forest ecosystems. 

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4. Increased Biological Productivity and Appearance of Black Foraminifera Due to Large Eruptions in the Past 150,000 Years at Low-Latitudes

   Martinez, V; Cruz, N; Abbott, D; Wu, J (February 2024, Proceedings American Geophysical Union)

   Abbott, D (Ed.)

   Volcanic eruptions deposit Fe-bearing volcanic ash in the ocean, thereby increasing biological productivity. The increased organic matter in areas of high biological productivity uses up oxygen as this organic matter decays and sinks through the water column. Past living beings, like foraminifera, ate organic matter that was carbon-rich and sometimes had metals absorbed into their carbon, creating coatings inside and outside their shells. These coatings can tell us about how biological productivity was affected before, during, and after the volcanic eruption. The studied cores are from the northwest Pacific Ocean and are close to geologically young volcanoes that are not well understood. The two cores that we focused on were VM28-309 and VM36-15 both taken by the Vema research ship. We studied the relationship between ash deposition and biological productivity by looking at all the ash layers in both cores. We found that in most of the ash layers, there were black or dark-colored foraminifera with coatings inside and outside the shells that were often carbon-rich and sometimes metal-rich. We attribute this coating to the increase of organic matter in surface waters when there was deposition of large amounts of volcanic ash. We also found high concentrations of Barium metal in VM28-309. Barium (Ba) is a biological marker because most or all Ba originates from the organic matter contained in sediments. We found that ash layers containing the finest materials (<38 micrometers in size) had the highest Ba content. For accurate results, we must sample above and below ash layers and select more sediment cores in the area. Also, Barium corrections must be done using data on biogenic silica contents. Loss on ignition (LOI) data will give us an estimate of the total organic carbon in each sample- allowing a second direct assessment of the increase in biological productivity produced by the deposition of volcanic ash. 

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5. Wave overtopping due to harbour resonance

   https://doi.org/10.1016/j.coastaleng.2021.103973  

   Maravelakis, Nikolaos; Kalligeris, Nikos; Lynett, Patrick J.; Skanavis, Vassilios L.; Synolakis, Costas E. (October 2021, Coastal Engineering)