We compared two new Earth observation based long-term global vegetation index products used in global change research (Global Inventory Modeling and Mapping Studies and Vegetation Index and Phenology Lab- VIP version 3). The two products showed a high level of consistency throughout the primary growing season and were less consistent during green-up and brown-down that impacted trends in phenology. VIP was generally higher and more variable leading to poorer correlations with in situ data

The aim of this study is to implement, calibrate and evaluate the CLM4 against carbon and hydrology observations from a shading and labeling experiment in a stand of young loblolly pines. We found a combination of parameters measured on-site and calibration targeting biomass, transpiration, and ¹³C discrimination gave good agreement with pretreatment measurements. We also used observations from the experiment to develop a conceptual model of short-term photosynthate storage and transport.

The diversity of microalgae and cyanobacteria in cryoconites on three high-Arctic glaciers was investigated. Possible bottom-up controls via nutrient limitation, wind dispersal, and hydrological stability were measured. Grazer populations were quantified to estimate the effect of top-down controls. Nutrient limitation appeared to be the most important control on the diversity and competition outcomes of microalgae and cyanobacteria.

The pan-boreal biome (> N45°) removes CO₂ from the atmosphere (i.e., it is a carbon sink). Fires can alter this carbon balance because they release CO₂ to the atmosphere but also initiate a long-term carbon sink during post-fire vegetation recovery. We found that historical fires of 1850–2009 have a small net sink contribution (~6 %) to the 2000–2009 regional carbon sink, which is a balance between immediate source effect of fires in 2000–2009 and sink effects of those in 1850–1999.

We studied organic carbon and the dissolved greenhouse gases carbon dioxide (CO2) and carbon monoxide (CO) in two estuaries in Sarawak, Malaysia, whose coast is covered by carbon-rich peatlands. The estuaries received terrestrial organic carbon from peat-draining tributaries. A large fraction was converted to CO2 and a minor fraction to CO. Both gases were released to the atmosphere. This shows how these estuaries function as efficient filters between land and ocean in this important region.

Peatlands have been exposed to nitrogen (N) deposition in Europe for decades. In this greenhouse study we investigated how N concentration and mobility in plants and peat have responded by sampling five sites across Europe and experimentally depositing labeled nitrogen on samples in a greenhouse. The peat moss retained its ability to absorb labeled nitrogen, but in the polluted sites more of it reached the deeper peat and was taken up by shrubs and grasses, indicating increased mobility of N.

We present a generic flux-limiting approach to simultaneously handle the availability limitation from many substrates, a problem common in all biogeochemical models. Our approach does not have the ordering problem like a few existing ad hoc approaches, and is straightforward to implement. Our results imply that significant uncertainties could have occurred in many biogeochemical models because of the improper handling of the substrate co-limitation problem.

Our study demonstrates that rare earth elements and yttrium (REY) accumulating in mussel shells emerge as potential proxies for environmental changes. Focusing on pH and temperature variation effects on the distribution of REY in seawater, we show that shells incorporate the free REY³⁺ species and that decreasing pH leads to increased REY concentrations, while rising temperatures impact the REY distribution pattern with minor effects on the absolute REY concentrations in shells.

We present a new approach for modelling coupled phenology and carbon allocation in savannas, and test it using data from the OzFlux network. Model behaviour emerges from complex feedbacks between the plant physiology and vegetation dynamics, in response to resource availability, and not from imposed hypotheses about the controls on tree-grass co-existence. Results indicate that resource limitation is a stronger determinant of tree cover than disturbance in Australian savannas.

Lake Ohrid is situated in the southern Balkans between Albania and Macedonia. It is a unique ecosystem with remarkable biodiversity and a sediment record of past climates that goes back more than a million years. Detailed reconstructions of past climate development and human alteration of the environment require underpinned and so in this study we go the present-day lake vegetation and catchment soils and test new proxies over one of the known recent cooling events of the region 8200 years ago.

Concentrations of major ions and trace metals were measured in aerosols off the coast of Peru in December 2012. A few trace metals (iron, copper, nickel, and cobalt) had anomalously high concentrations, which may be associated with industrial metal smelting activities in the region. The atmosphere appears to supply an excess of iron (relative to atmospheric nitrogen supply) to the phytoplankton community of the Peruvian upwelling system.

We measured the nitrous oxide (N₂O) distribution in the water column in the oxygen minimum zone off Peru, an area with extremely high N₂O emissions. Our data show very variable and often very high N₂O concentrations in the water column at the coast, which lead to high N₂O emissions when these waters are brought to the surface. The very high N₂O production off Peru may be caused by high nutrient turnover rates together with rapid changes in the oxygen concentrations.

Alkalinity released from sediments of the southern North Sea can play an important role in the carbon cycle of the North Sea by lowering the pCO₂ of the seawater and thus increasing the CO₂ flux between the atmosphere and the water. However, not every single mole alkalinity generated in sediments leads to an additional CO₂ uptake, as certain reactions in the water column can negate the respective alkalinity release.

Unlike the positive relationship reported before between partial pression of carbon dioxide and dissolved organic carbon for lake waters, we found no significant relationship in our low-latitude lakes, despite very broad ranges in both variables. The strength of this relationship declines with increasing water temperature, suggesting substantial differences in carbon cycling in warm lakes, which must be considered when upscaling limnetic carbon cycling to global scales.

A step in the annual average CO₂ difference between Mauna Loa and the Southern Hemisphere of 0.8 ppm in 2009–2010 has no precedence in 50 years. Variations in interhemispheric exchange coincide with the step, the subsequent 5-year north-south CO₂ stability, and historic differences. This behaviour provides a critical test for studies that employ atmospheric transport models to interpret global carbon budgets and inform management of anthropogenic emissions.