Assessing the Status of Wild Felids in a Highly-Disturbed Commercial Forest Reserve in Borneo and the Implications for Camera Trap Survey Design

The proliferation of camera-trapping studies has led to a spate of extensions in the known distributions of many wild cat species, not least in Borneo. However, we still do not have a clear picture of the spatial patterns of felid abundance in Southeast Asia, particularly with respect to the large areas of highly-disturbed habitat. An important obstacle to increasing the usefulness of camera trap data is the widespread practice of setting cameras at non-random locations. Non-random deployment interacts with non-random space-use by animals, causing biases in our inferences about relative abundance from detection frequencies alone. This may be a particular problem if surveys do not adequately sample the full range of habitat features present in a study region. Using camera-trapping records and incidental sightings from the Kalabakan Forest Reserve, Sabah, Malaysian Borneo, we aimed to assess the relative abundance of felid species in highly-disturbed forest, as well as investigate felid space-use and the potential for biases resulting from non-random sampling. Although the area has been intensively logged over three decades, it was found to still retain the full complement of Bornean felids, including the bay cat Pardofelis badia, a poorly known Bornean endemic. Camera-trapping using strictly random locations detected four of the five Bornean felid species and revealed inter- and intra-specific differences in space-use. We compare our results with an extensive dataset of >1,200 felid records from previous camera-trapping studies and show that the relative abundance of the bay cat, in particular, may have previously been underestimated due to the use of non-random survey locations. Further surveys for this species using random locations will be crucial in determining its conservation status. We advocate the more wide-spread use of random survey locations in future camera-trapping surveys in order to increase the robustness and generality of inferences that can be made.     

Acceleration of high gravity yeast fermentations by acetaldehyde addition

In high gravity Saccharomyces cerevisiae fermentations containing 300 g glucose l^–1, daily addition of acetaldehyde to a total of 93 mM shortened the time required to ferment the first 250 g glucose l^–1 from 790 h to 585 h. Acetaldehyde feeding had no effect on the ethanol yield but increased by 135%, 78% and 77% the final concentrations of 2,3-butanediol, 2-methylpropanol and acetate, while decreasing that of glycerol by 14%. Controlled acetaldehyde feeding has potential as a technique for accelerating high gravity fuel or industrial ethanol fermentations and may be useful in preventing incomplete fermentations.     

Compositional Characterization and Pyrolysis of Loblolly Pine and Douglas-fir Bark

Two potential biofuel resources, Douglas-fir and Loblolly pine bark, were subjected to extensive chemical and compositional analysis. The barks were initially extracted with dichloromethane, and the resulting extracted compounds were characterized by gas chromatography coupled with mass spectrometric analysis. Characterization of the major bark biocomponents indicated that Douglas-fir and Loblolly pine bark contained 22.5 and 13.2 % tannins, 44.2 and 43.5 % lignin, 16.5 and 23.1 % cellulose, and 7.6 and 14.1 % hemicellulose, respectively. Of particular interest is the high content of tannins and lignin, which make these barks excellent potential precursors for bio-oils and/or other value-added chemicals. ¹³C nuclear magnetic resonance (NMR) was used to characterize the chemical structure of the lignin and tannins. These samples were also analyzed by ³¹P NMR after phosphitylation of the hydroxyl groups in lignin and tannins. The NMR spectral data indicated that the lignin in both barks contained p-hydroxyphenyl (h) and guaiacyl (g) of lignin monomers with an h/g ratio of 10:90 and 22:78 for Douglas-fir and Loblolly pine bark, respectively. Gel permeation chromatography was used to analyze the molecular weight distributions of extracted tannins, isolated cellulose, and ball-milled lignin. The pyrolysis of Douglas-fir and pine bark at 500°C in a tubular reactor generated 48.2 and 45.2 % of total oil, of which the light oil contents are 14.1 and 20.7 % and heavy oil are 34.1 and 24.4 %. Similarly, fast pyrolysis at 375°C yielded 56.1 and 49.8 % of total oil for Douglas-fir and pine bark, respectively.