A large fluvial pulse of organic carbon following the Bornean peat swamp forest fires of 2009

Tropical peatlands are high carbon density ecosystems that are currently extremely vulnerable to destabilisation through human and climate induced changes. They contain 89 Gt carbon (3% global soil carbon) but rapid land use changes (deforestation, drainage) and consequent fire are rapidly releasing this. There are approximately 27.1 million hectares (Mha) (an area approximately equivalent in size to the UK) of peatland in Southeast Asia which accounts for around 56% of all tropical peatlands worldwide. 20.7 Mha (83%) is found in Indonesia, primarily in Eastern Sumatra and Central Kalimantan. The dry season of 2009 (May-October) proved to be one of the most intense Bornean fire events since 1997. We sought to establish how fluvial carbon dynamics in tropical peat rich catchments were affected in the period following these catastrophic fires. Fluvial carbon fluxes were quantified from 8 channels draining peat swamp forest (PSF) catchments in Central Kalimantan, Borneo from weekly measurements over a 6-month period immediately following the end of the fire period. These included 5 channels draining degraded PSF catchments that were subject to fires during the dry season of 2009 and 3 channels draining intact PSF that was unaffected by the fires. Cumulative total organic carbon (TOC) fluxes for the duration of the study were 32 to 68% larger in the catchment channels that had been affected by fire, when compared to fluxes during the same interval in the previous year (which was unexceptional in terms of fire). This is in marked contrast to channels draining the intact (no fire) forest where there were no differences observed in fluxes. Concentration data demonstrates that there was an initial decrease in dissolved organic carbon (DOC) concentration and an increase in particulate organic carbon (POC) immediately following the onset of the first rains which continued for ~1 month until reaching similar levels to the corresponding period in the previous year. For DOC fluxes (the largest fraction) this decrease in concentration was more than offset by a large increase in fluvial discharge (from decreased transpiration and increased runoff through denuded vegetation cover) which contributed an overall net increase in flux. The fire-stimulated increase in fluvial carbon flux is set against a pattern of higher fluxes in the degraded catchments established during the pre-fire year where oxidation of the peat column results in high losses. Our data are the first to demonstrate a large and sustained pulse of fluvial carbon following large scale fires in carbon rich tropical PSF. They point to a previously uncharacterised pathway of carbon loss from these vast carbon stores and they underscore the vulnerability of these stores when subject to anthropogenic disturbance

Semi-classical limit and minimum decoherence in the Conditional Probability Interpretation of Quantum Mechanics

The Conditional Probability Interpretation of Quantum Mechanics replaces the abstract notion of time used in standard Quantum Mechanics by the time that can be read off from a physical clock. The use of physical clocks leads to apparent non-unitary and decoherence. Here we show that a close approximation to standard Quantum Mechanics can be recovered from conditional Quantum Mechanics for semi-classical clocks, and we use these clocks to compute the minimum decoherence predicted by the Conditional Probability Interpretation.Comment: 8 pages, references adde

Adaptive strategies used by surgical teams under pressure:an interview study among senior healthcare professionals in four major hospitals in the United Kingdom

BackgroundHealthcare systems are operating under substantial pressures, and often simply cannot provide the standard of care they aspire to within the available resources. Organisations, managers, and individual clinicians make constant adaptations in response to these pressures, which are typically improvised, highly variable and not coordinated across clinical teams. The purpose of this study was to identify and describe the types of everyday pressures experienced by surgical teams and the adaptive strategies they use to respond to these pressures.MethodsWe conducted interviews with 20 senior multidisciplinary healthcare professionals from surgical teams in four major hospitals in the United Kingdom. The interviews explored the types of everyday pressures staff were experiencing, the strategies they use to adapt, and how these strategies might be taught to others.ResultsThe primary pressures described by senior clinicians in surgery were increased numbers and complexity of patients alongside shortages in staff, theatre space and post-surgical beds. These pressures led to more difficult working conditions (e.g. high workloads) and problems with system functioning such as patient flow and cancellation of lists. Strategies for responding to these pressures were categorised into increasing or flexing resources, controlling and prioritising patient demand and strategies for managing the workload (scheduling for efficiency, communication and coordination, leadership, and teamwork strategies).ConclusionsTeams are deploying a range of strategies and making adaptations to the way care is delivered. These findings could be used as the basis for training programmes for surgical teams to develop coordinated strategies for adapting under pressure and to assess the impact of different combinations of strategies on patient safety and surgical outcomes

Quantifying Dynamics in Tropical Peat Swamp Forest Biomass with Multi- Temporal LiDAR Datasets

Tropical peat swamp forests in Indonesia store huge amounts of carbon and are responsible for enormous carbon emissions every year due to forest degradation and deforestation. These forest areas are in the focus of REDD+ (reducing emissions from deforestation, forest degradation, and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks) projects, which require an accurate monitoring of their carbon stocks or aboveground biomass (AGB). Our study objective was to evaluate multi-temporal LiDAR measurements of a tropical forested peatland area in Central Kalimantan on Borneo. Canopy height and AGB dynamics were quantified with a special focus on unaffected, selective logged and burned forests. More than 11,000 ha were surveyed with airborne LiDAR in 2007 and 2011. In a first step, the comparability of these datasets was examined and canopy height models were created. Novel AGB regression models were developed on the basis of field inventory measurements and LiDAR derived height histograms for 2007 (r(2) = 0.77, n = 79) and 2011 (r(2) = 0.81, n = 53), taking the different point densities into account. Changes in peat swamp forests were identified by analyzing multispectral imagery. Unaffected forests accumulated on average 20 t/ha AGB with a canopy height increase of 2.3 m over the four year time period. Selective logged forests experienced an average AGB loss of 55 t/ha within 30 m and 42 t/ha within 50 m of detected logging trails, although the mean canopy height increased by 0.5 m and 1.0 m, respectively. Burned forests lost 92% of the initial biomass. These results demonstrate the great potential of repetitive airborne LiDAR surveys to precisely quantify even small scale AGB and canopy height dynamics in remote tropical forests, thereby featuring the needs of REDD+

Quantifying tropical peatland dissolved organic carbon (DOC) using UV-visible spectroscopy

UV–visible spectroscopy has been shown to be a useful technique for determining dissolved organic carbon (DOC) concentrations. However, at present we are unaware of any studies in the literature that have investigated the suitability of this approach for tropical DOC water samples from any tropical peatlands, although some work has been performed in other tropical environments. We used water samples from two oil palm estates in Sarawak, Malaysia to: i) investigate the suitability of both single and two-wavelength proxies for tropical DOC determination; ii) develop a calibration dataset and set of parameters to calculate DOC concentrations indirectly; iii) provide tropical researchers with guidance on the best spectrophotometric approaches to use in future analyses of DOC. Both single and two-wavelength model approaches performed well with no one model significantly outperforming the other. The predictive ability of the models suggests that UV–visible spectroscopy is both a viable and low cost method for rapidly analyzing DOC in water samples immediately post-collection, which can be important when working at remote field sites with access to only basic laboratory facilities

Water use efficiency and yield of winter wheat under different irrigation regimes in a semi-arid region

In irrigation schemes under rotational water supply in semi-arid region, the water allocation and irrigation scheduling are often based on a fixed-area proportionate water depth with every irrigation cycle irrespective of crops and their growth stages, for an equitable water supply. An experiment was conducted during the 2004- 2005 season in Haouz irrigated area in Morocco, which objective was 1) to evaluate the effects of the surface irrigation scheduling method (ex-isting rule) adopted by the irrigation agency on winter wheat production compared to a full ir-rigation method and 2) to evaluate drip irrigation versus surface irrigation impacts on water sav-ing and yield of winter wheat. The methodology was based on the FAO-56 dual approach for the surface irrigation scheduling. Ground measure- ments of the Normalized Difference Vegetation Index (NDVI) were used to derive the basal crop coefficient and the vegetation fraction cover. The simple FAO-56 approach was used for drip irrigation scheduling. For surface irrigation, the existing rule approach resulted in yield and WUE reductions of 22% and 15%, respectively, compared with the optimized irrigation sched-uling proposed by the FAO-56 for full irrigation treatment. This revealed the negative effects of the irrigation schedules adopted in irrigation schemes under rotational water supply on crops productivity. It was also demonstrated that drip irrigation applied to wheat was more efficient with 20% of water saving in comparison with surface irrigation (full irrigation treatment). Drip irrigation gives also higher wheat yield com-pared to surface irrigation (+28% and +52% for full irrigation and existing rule treatments re-spectively). The same improvement was ob-served for water use efficiency (+24% and +59% respectively)