This study investigates microbial nutrient limitation patterns across a region of southwest Greenland in relation to environmental factors. Using microbial enzyme activities to infer nutrient limitation patterns, we determined that most lakes are P-limited. Further, P limitation was tightly controlled by lake dissolved organic carbon (DOC) concentration.

Our findings suggest that the mechanisms underlying the carbon sinks for natural and planted forests of China differ markedly with various effects from areal expansion and increase in carbon density. The increasing trend in the relative contribution of forest growth to carbon sinks for planted forests highlights that afforestation will continue to increase the carbon sink of China's forests in the future, subject to persistently increasing forest growth after the establishment of plantations.

We examined the variables controlling fire severity and the amount of vegetation burnt during wildfires and prescribed burns. Fire severity varied strongly within and between wildfires in relation to fire-weather conditions and vegetation type. The amount of surface vegetation burnt was a function of the amount present pre-fire, whilst moss layer consumption related to prolonged dry periods. Moss flammability may explain the higher carbon-release during wildfires compared to prescribed burns.

In this study we test whether river outlet chemistry can be used as an additional source of information to improve the prediction of the total organic carbon (TOC) of headwaters, relative to models based on map information alone. Including river outlet TOC as a predictor in the models gave 5-15 % lower prediction errors than using map information alone. Thus, data on water chemistry measured at river outlets offer information which can complement GIS-based modelling of headwaters chemistry.

Our study showed significant relationships among root traits indicating an acquisition-conservation tradeoff for thin absorptive roots while no such trait relationships were found for thick absorptive roots. The findings support our hypothesis that root economic strategies differ with increasing root diameter. The contrasting economic strategies between thin and thick absorptive roots, as revealed here, may provide a new perspective on our understanding of the root economics spectrum.

This simulation study found that dry legacy imposed positive impacts on net ecosystem production (NEP) whereas wet legacy had negative impacts on NEP, indicating that dry legacy can foster more C sequestration and wet legacy more C release. The carryover of soil nitrogen was mainly responsible for the gross ecosystem production (GEP) responses, while the carryovers of plant biomass, litter and soil organic matter were mainly responsible for the ecosystem respiration (Re) responses.

– Effects of ocean acidification in shelf waters on fish yield can be of the same order of magnitude as climatic impacts. – Local differences in response within one shelf sea due to different governing hydrodynamic regimes and variation in importance of benthic food web. – Future fish yields in the North Sea: seasonally stratified areas show increased yield, transitional waters show decreased yield and permanently mixed waters show increased yield moderated by acidification impacts.

Phytoplankton patchiness in the northeastern SCS during May 2014 could be largely controlled by vertical nutrient fluxes including turbulent diffusion and curl-driven upwelling. There was an increasing turbulent diffusion but decreasing curl-driven upwelling from the coastal upwelling zones to the offshore pelagic zones. Elevated fluxes near Dongsha led to net growth of a diatom-rich community, whereas low fluxes near southwest Taiwan resulted in a decline of a picoplankton bloom.

The principal objective of the present work is to quantify the fractions of the principal sources of sedimentary organic matter (SOM) in floodplain lakes of the central Amazon basin. The results indicate that the main source of SOM is not the riverine particulate material, as postulated by the literature, but the macrophytes and the forests.

The paper presents the results of a fossil invertebrates study in four caves of the Romanian Carpathians, to complement paleoenvironmental data previously reported. Oribatid mites and ostracods are the most common invertebrates in the studied cave sediments. By corroborating the fossil invertebrates' record with the information given by magnetic properties and sediment structures, complementary data on past vegetation, temperatures, and hydraulic regimes could be gathered.

Rivers transport a large amount of carbon as dissolved organic carbon (DOC). Our incubation experiments on water of the Tana River, Kenya, showed that microbial decomposition of 10–60 % of the initial DOC occurred within the first 24–48 h. Simultaneously, there was a decrease in isotopic composition, indicating that DOC derived from C₄ vegetation is preferentially decomposed. This has implications for the assessment of vegetation in a catchment based on isotope signatures of riverine carbon.

Revegetation of degraded arable land with perennial legumes in semiarid areas of China is expected to increase soil carbon sequestration. In this study we assessed the effect of alfalfa, bush clover and milk vetch on the SOC concentration and SOC stock accumulated annually over a 2 m soil profile. The results indicated that conversion of arable land to perennial legume pasture resulted in a significant increase in SOC, particularly at soil depths below 1 m.

Our interdisciplinary research brings together methodologies from hydrology, soil science and biogeochemistry to address key questions about the transport of cattle slurry in the environment. The paper provides a novel approach to trace dissolved and particulate components of cattle slurry through an experimental hillslope system. This work provides one of the first examples of using biomarkers to assess the effects of slope gradient and rainfall intensity on the movement of slurry derived-OM.

Bed sediments from the Sacramento-San Joaquin River Delta (CA) were fractionated according to density and analyzed for sediment mass distribution, elemental (C and N) composition, mineral surface area, and stable carbon and radiocarbon isotope compositions of organic carbon (OC) and fatty acids to evaluate the nature of organic carbon in river sediments. These data demonstrate the complex source and age distributions within river sediments.

Colored dissolved organic matter (CDOM) is a factor in determining penetration of light in estuaries. Important plant species growing in the beds of estuaries depend on such light penetration for survival. Previous studies have used CDOM fluorescence to approximate light absorption by CDOM but have found variable relationships between fluorescence and absorbance. This paper describes this variability in three east coast estuaries, and shows that this conversion is dependent on CDOM source.

Arctic region is experiencing an unprecedented rise in permafrost temperatures leading to permafrsot thawing with dire implications for ecosystem structure and functioning. Therefore, it imperative to understand the behaviour of Arctic ecosystems under present climatic conditions so that we are equipped with the information to predict their future behaviour. This study presents field data on methane exchange from Seida, located in NW Siberia, Russia measured using various biogeochemical tools.

We have quantified large-scale forest loss over a 21-year period (1990–2010) in the tropical biomes of South America using a new satellite-based data set. We found that South American forest exhibited interannual variability without a clear trend during the 1990s, but increased from 2000 to 2004. After 2004, forest loss decreased again, mainly as a result of a decrease in the Brazilian Amazon, whereas at the same time regions south of the arc of deforestation showed an increase in forest loss.