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Carbon balance of a grazed savanna grassland ecosystem in South Africa

Tropical savannas and grasslands are estimated to contribute significantly to the total primary production of all terrestrial vegetation. Large parts of African savannas and grasslands are used for agriculture and cattle grazing, but the carbon flux data available from these areas are limited. This study explores carbon dioxide fluxes measured with the eddy covariance method for 3 years at a graze

Building local institutions for national conservation programs: lessons for developing Reducing Emissions from Deforestation and Forest Degradation (REDD+) programs

ABSTRACT. For programs that aim to promote forest conservation and poverty alleviation, such as Reducing Emissions from Deforestation and Forest Degradation (REDD+), the participation of indigenous communities is essential to meet program goals. Using Ostrom's theory of collective action for common pool resource management, we evaluated the institutions governing indigenous participation in the Pr

Seasonal trends of Amazonian rainforest phenology, net primary productivity, and carbon allocation

The seasonality of solar irradiance and precipitation may regulate seasonal variations in tropical forests carbon cycling. Controversy remains over their importance as drivers of seasonal dynamics of net primary productivity in tropical forests. We use ground data from nine lowland Amazonian forest plots collected over 3 years to quantify the monthly primary productivity (NPP) of leaves, reproduct

RESPIRATION OF TERRESTRIALLY-DERIVED ORGANIC MATTER PLAYS A RELATIVELY SMALL ROLE IN COASTAL ACIDIFICATION

Increased estuarine input and subsequent degradation of dissolved organic carbon (DOC) is a potentially important cause of rising CO2 concentrations that contribute to coastal marine acidification. However, it is not clear whether or not the evolved CO2 originates from the decomposition of terrestrially-derived DOC. We recorded the changes in δ13C and δ2H of dissolved organic matter during laborat

Air quality impacts of European wildfire emissions in a changing climate

Wildfires are not only a threat to human property and a vital element of many ecosystems, but also an important source of air pollution. In this study, we first review the available evidence for a past or possible future climate-driven increase in wildfire emissions in Europe. We then introduce an ensemble of model simulations with a coupled wildfire-dynamic-ecosystem model, which we combine with

Very high CO2 exchange fluxes at the peak of the rainy season in a West African grazed semi-arid savanna ecosystem

Africa is a sink of carbon, but there are large gaps in our knowledge regarding the CO2 exchange fluxes for many African ecosystems. Here, we analyse multi-annual eddy covariance data of CO2 exchange fluxes for a grazed Sahelian semi-arid savanna ecosystem in Senegal, West Africa. The aim of the study is to investigate the high CO2 exchange fluxes measured at the peak of the rainy season at the Da

The status and challenge of global fire modelling

Biomass burning impacts vegetation dynamics, biogeochemical cycling, atmospheric chemistry, and climate, with sometimes deleterious socio-economic impacts. Under future climate projections it is often expected that the risk of wildfires will increase. Our ability to predict the magnitude and geographic pattern of future fire impacts rests on our ability to model fire regimes, using either well-fou

Wildfire air pollution hazard during the 21st century

Wildfires pose a significant risk to human livelihoods and are a substantial health hazard due to emissions of toxic smoke. Previous studies have shown that climate change, increasing atmospheric CO2, and human demographic dynamics can lead to substantially altered wildfire risk in the future, with fire activity increasing in some regions and decreasing in others. The present study re-examines the

Organic phosphorus in the terrestrial environment : a perspective on the state of the art and future priorities

Background: The dynamics of phosphorus (P) in the environment is important for regulating nutrient cycles in natural and managed ecosystems and an integral part in assessing biological resilience against environmental change. Organic P (Po) compounds play key roles in biological and ecosystems function in the terrestrial environment being critical to cell function, growth and reproduction. Scope:

Early snowmelt significantly enhances boreal springtime carbon uptake

We determine the annual timing of spring recovery from spaceborne microwave radiometer observations across northern hemisphere boreal evergreen forests for 1979–2014. We find a trend of advanced spring recovery of carbon uptake for this period, with a total average shift of 8.1 d (2.3 d/decade). We use this trend to estimate the corresponding changes in gross primary production (GPP) by applying i

Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European bee

Historic global biomass burning emissions for CMIP6 (BB4CMIP) based on merging satellite observations with proxies and fire models (1750-2015)

Fires have influenced atmospheric composition and climate since the rise of vascular plants, and satellite data have shown the overall global extent of fires. Our knowledge of historic fire emissions has progressively improved over the past decades due mostly to the development of new proxies and the improvement of fire models. Currently, there is a suite of proxies including sedimentary charcoal

Isoprenoid emission variation of Norway spruce across a European latitudinal transect

Norway spruce (Picea abies) is one of the dominant tree species in the European boreal zone with the capacity to grow over large areas within Europe. It is an important emitter of biogenic volatile organic compounds (BVOCs), which can act as precursors of photochemical smog and ozone and contribute to the formation and growth of secondary organic aerosols (SOA) in the atmosphere.Isoprenoid emissio

What controls variation in carbon use efficiency among Amazonian tropical forests?

Why do some forests produce biomass more efficiently than others? Variations in Carbon Use Efficiency (CUE: total Net Primary Production (NPP)/ Gross Primary Production (GPP)) may be due to changes in wood residence time (Biomass/NPPwood), temperature, or soil nutrient status. We tested these hypotheses in 14, one ha plots across Amazonian and Andean forests where we measured most key components o

From Agricultural Benefits to Aviation Safety : Realizing the Potential of Continent-Wide Radar Networks

Migratory animals provide a multitude of services and disservices-with benefits or costs in the order of billions of dollars annually. Monitoring, quantifying, and forecasting migrations across continents could assist diverse stakeholders in utilizing migrant services, reducing disservices, or mitigating human-wildlife conflicts. Radars are powerful tools for such monitoring as they can assess dir

How are biodiversity and dispersal of species affected by the management of roadsides? A systematic map

Background: In many parts of the world, roadsides are regularly managed for traffic-safety reasons. Hence, there are similarities between roadsides and certain other managed habitats, such as wooded pastures and mown or grazed grasslands. These habitats have declined rapidly in Europe during the last century. For many species historically associated with them, roadsides may function as new primary

Short-term carbon input increases microbial nitrogen demand, but not microbial nitrogen mining, in a set of boreal forest soils

Rising carbon dioxide (CO2) concentrations and temperatures are expected to stimulate plant productivity and ecosystem C sequestration, but these effects require a concurrent increase in N availability for plants. Plants might indirectly promote N availability as they release organic C into the soil (e.g., by root exudation) that can increase microbial soil organic matter (SOM) decomposition (“pri