We used a 3-D coupled hydrodynamic–biogeochemical water quality model to investigate the effects of changes in catchment nutrient loading and composition on the phytoplankton dynamics, development of hypoxia and internal nutrient dynamics in a stratified coastal lagoon system. The results highlighted the need to reduce both total nitrogen and total phosphorus for water quality improvement in estuarine systems.

Understanding the sensitivity of transpiration to stomatal conductance is critical to simulating the water cycle. This sensitivity is a function of the degree of coupling between the vegetation and the atmosphere. We combined an extensive literature summary with estimates of coupling derived from FLUXNET data. We found notable departures from the values previously reported. These data form a model benchmarking metric to test existing coupling assumptions.

Trichodesmium is significant marine N₂ fixer. We conducted short- and long-term UV exposure experiment to investigate how UV affects this organism. Our results showed N₂ fixation and carbon fixation rates were significantly reduced under UV radiation. As a defense strategy, Trichodesmium is able to synthesize UV-absorbing compounds to protect from UV damage. Our results suggest that shipboard experiments in UV-opaque containers may have substantially overestimated in situ N₂ fixation rate.

An improvement in our process-based understanding of CO₂ exchanges in the Arctic and their climate sensitivity is critical. With continued warming temperatures and longer growing seasons, tundra systems will likely increase rates of C cycling, although shifts in sink strength could take place, challenging the forecast of upcoming C states. In this context, we investigated the functional responses of C exchange to environmental characteristics across 8 consecutive years in West Greenland.

Red calcified seaweeds in UK rock pools have seasonal patterns in growth and photosynthesis driven by seawater temperature, light and the chemistry of rock pool water. This is important given future changes in environmental factors such as climate change and ocean acidification. Photosynthesis and calcification are strongly coupled and depend on light and temperature, whilst dissolution is regulated by rock pool water chemistry and is thus particularly vulnerable to environmental change.

In this study, we present a coupled physical–biogeochemical model, in which the acclimation of autotrophs to their resource environment is resolved based on optimality arguments. The model is implemented in the southern North Sea, a shallow coastal system. Based on comparisons with multiple data sources, we show that the model can reproduce the variability in the system for the period 2000–2010 and analyze the mechanisms driving the large-scale, persistent coastal gradients in the system.

According to this study, Artemisia ordosica escaped water limitations by invoking a water-conservation strategy with the regulation of stomatal conductance and advancement of sap-flow peaking time, manifesting in a hysteresis effect. This study provides a significant contribution to the understanding of acclimation processes in desert-shrub species to drought-associated stress in dryland ecosystems.