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The forests of Kalimantan are under severe pressure from extensive land use activities dominated by logging, palm oil plantations, and peatland fires. To implement the forest moratorium for mitigating greenhouse gas emissions, Indonesia's government requires information on the carbon stored in forests, including intact, degraded, secondary, and peat swamp forests. We developed a hybrid approach of producing a wall-to-wall map of the aboveground biomass (AGB) of intact and degraded forests of Kalimantan at 1 ha grid cells by combining field inventory plots, airborne lidar samples, and satellite radar and optical imagery. More than 110 000 ha of lidar data were acquired to systematically capture variations of forest structure and more than 104 field plots to develop lidar-biomass models. The lidar measurements were converted into biomass using models developed for 66 439 ha of drylands and 44 250 ha of wetland forests. By combining the AGB map with the national land cover map, we found that 22.3 Mha (106 ha) of forest remain on drylands ranging in biomass from 357.2 ± 12.3 Mgha−1 in relatively intact forests to 134.2 ± 6.1 Mgha−1 in severely degraded forests. The remaining peat swamp forests are heterogeneous in coverage and degradation level, extending over 3.62 Mha and having an average AGB of 211.8 ± 12.7 Mgha−1. Emission factors calculated from aboveground biomass only suggest that the carbon storage potential of more than 15 Mha of degraded and secondary dryland forests will be about 1.1 PgC.

Objective: To investigate the effect of intramedullary (IM) pin size in combination with various monocortical screw configurations on construct stiffness and strength as well as plate stain in locking compression plate-rod (LCPR) constructs. Methods: A synthetic bone model with a 40mm fracture gap was used. LCPs with monocortical locking screws were tested with no pin (LCPMono) and IM pins of 20% (LCPR20), 30% (LCPR30) and 40% (LCPR40) of IM diameter. LCPs with bicortical screws (LCPBi) were also tested in the first paper. The first paper used screw configurations with 2 or 3 screws per fragment modelling long (8 hole), intermediate (6 hole) and short (4 hole) plate working lengths. Responses to axial compression, biplanar four point bending and axial load to failure were recorded. The second paper used 2 screws per fragment to model a long (8 hole) and short (4 hole) plate working length and strain responses to axial compression were recorded at 6 regions of the plate via 3D digital image correlation. Results: In the first paper, LCPBi were not significantly different from LCPMono control for any of the outcome variables measured. In bending, LCPR20 were not significantly different from LCPBi and LCPMono. LCPR30 were stiffer than LCPR20 and the controls. LCPR40 constructs were stiffer than all other constructs. The addition of an IM pin of any size provided a significant increase in axial stiffness and load to failure. This effect was incremental with increasing IM pin diameter. As plate working length decreased there was a significant increase in stiffness across all constructs. The addition of an IM pin of any size provided a significant decrease in plate strain. For the long working length, LCPR30 and LCPR40 had significantly lower strain than the LCPR20 and plate strain was significantly higher adjacent to the screw closest to the fracture site. For the short working length, there was no significant difference in strain across any LCPR constructs or at any regi

Landscape scale quantification enables farmers to pool resources and expertise. However, the problem remains of how to quantify these gains. This article considers current greenhouse gas (GHG) quantification methods that can be used in a landscape scale analysis in terms of relevance to areas dominated by smallholders in developing countries. In landscape scale carbon accounting frameworks, measurements are an essential element. Sampling strategies need careful design to account for all pools/fluxes and to ensure judicious use of resources. Models can be used to scale-up measurements and fill data gaps. In recent years a number of accessible models and calculators have been developed which can be used at the landscape scale in developing country areas. Some are based on the Intergovernmental Panel on Climate Change (IPCC) method and others on dynamic ecosystem models. They have been developed for a range of different purposes and therefore vary in terms of accuracy and usability. Landscape scale assessments of GHGs require a combination of ground sampling, use of data from census, remote sensing (RS) or other sources and modelling. Fitting of all of these aspects together needs to be performed carefully to minimize uncertainties and maximize the use of scarce resources. This is especially true in heterogeneous landscapes dominated by smallholders in developing countries.

Combining measurements taken using the Wilkinson Microwave Anisotropy Probe (WMAP) from 2001 to 2008 with measurements taken using Planck from 2009 to 2010, we investigate the long-term flux density variability of extragalactic radio sources selected from the Planck Early Release Compact Source Catalogue. The single-year, single-frequency WMAP maps are used to estimate yearly-averaged flux densities of the sources in the four WMAP bands: Ka (33 GHz), Q (41 GHz), V (61 GHz), and W (94 GHz). We identify 82, 67, 32, and 15 sources respectively as variable at greater than 99% confidence level in these four bands. The amplitudes of variation are comparable between bands, and are not correlated with either the flux densities or the spectral indices of the sources. The number counts of WMAP Ka-band sources are stable from year to year despite the fluctuation caused by individual source variability. Most of our sources show strong correlation in variability between bands. Almost all the sources that show variability are blazars. We have attempted to fit two simple, four-parameter models to the time-series of 32 sources showing correlated variability at multiple frequencies - a long-term flaring model and a rotating-jet model. We find that 19 sources (60%) can be fit with the simple rotating-jet model, and ten of these also fit the simple long-term flaring model. The remaining 13 sources (40%) show more complex variability behaviour that is not consistent with either model. Extended radio galaxies in our sample show no sign of variability, as expected, with the exception of Pictor A for which we report evidence for a millimetre flare lasting between 2002 and 2010. © ESO 2013.

The C-Band All-Sky Survey (C-BASS) aims to produce sensitive, all-sky maps of diffuse Galactic emission at 5 GHz in total intensity and linear polarization. These maps will be used (with other surveys) to separate the several astrophysical components contributing to microwave emission, and in particular will allow an accurate map of synchrotron emission to be produced for the subtraction of foregrounds from measurements of the polarized Cosmic Microwave Background. We describe the design of the analog instrument, the optics of our 6.1 m dish at the Owens Valley Radio Observatory, the status of observations, and first-look data.

We have continued our monitoring program of ~1200 sources with the Owens Valley Radio Observatory 40 m Telescope. Most of the sources are part of the Candidate Gamma-Ray Blazar Survey (CGRaBS). We have also been observing Targets Of Opportunity triggered by gamma-ray detections and participating in multiwalength campaigns lead by Fermi-GST. Regular program sources are observed twice a week and have been observed for ~24 months at 15 GHz. We use these light curves to study the radio variability and its relation with optical properties. A significant fraction of the bright AGNs detected by Fermi-GST are in our program, which will allow for correlations between the radio and gamma-ray behavior for a number of sources. Here we present some example light curves, describe the tools used to study the variability and present some preliminary variability statistics for the sample.

We describe polarization observations of the CMBR with the Cosmic Background Imager, a 13 element interferometer which operates in the 26-36 GHz band from Llano de Chajnantour in northern Chile. The array consists of 90-cm Cassegrain antennas mounted on a steerable platform which can be rotated about the optical axis to facilitate polarization observations. The CBI employs single mode circularly polarized receivers which sample multipoles from ℓ~400 to ℓ~4250. The instrumental polarization of the CBI was calibrated with 3C279, a bright polarized point source which was monitored with the VLA.