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Dawson J.,Coral Cay Conservation | Turner C.,Jaquelin Fisher Associates | Pileng O.,Coral Cay Conservation | Pileng O.,Walindi Nature Center | And 5 more authors.
Tropical Conservation Science | Year: 2011

From June, 2007, to February, 2009, the Waria Valley Community Conservation and Sustainable Livelihoods Project (WVCP) completed an inventory survey of the birds of the lower Waria Valley, Morobe Province, Papua New Guinea. Four land use types -- agricultural, secondary forest edge, primary forest edge and primary forest -- were surveyed using Mackinnon list surveys. In total, 125 species representing 43 families were identified, of which 54 (43.2%) are endemic to the islands of New Guinea and the Bismark Archipelago. The avifauna of primary forest edge and primary forest was more species rich and diverse than that of agricultural habitats. Agricultural habitats also differed significantly in both overall community composition and some aspects of guild composition compared to all three forested habitats. Nectarivores and insectivore-frugivores formed a significantly larger proportion of species in agricultural habitats, whereas obligate frugivores formed a significantly greater proportion in forested habitats. We propose further survey and management initiatives that could help contribute to the conservation and sustainable use of the area's important biological resources. © Jeff Dawson, Craig Turner, Oscar Pileng, Andrew Farmer, Cara McGary, Chris Walsh, Alexia Tamblyn and Cossey Yosi. Source


Yosi C.K.,University of Melbourne | Yosi C.K.,Papua New Guinea Forest Research Institute | Keenan R.J.,University of Melbourne | Fox J.C.,University of Melbourne
Forest Ecology and Management | Year: 2011

Forest dynamics after timber harvesting is a major issue for tropical forest managers and communities. Timber harvesting provides income to communities and governments and resources to industry but it has also been identified as a potential contributor to deforestation and degradation of tropical forests. In Papua New Guinea (PNG) harvesting is primarily occurring in accessible primary forests however, the fate of these forests under current harvesting practices is poorly understood.In this study we investigated the impacts of selective harvesting on stand structure, growth and dynamics, recovery and degradation, and species diversity. We also assessed the impacts of forest fire after the 1997-98 El Nino on basal area (BA) growth and mortality rates of natural tropical forests in PNG. For this study we used data from 118 (105 in selectively harvested and 13 in un-harvested forest), one-hectare permanent sample plots distributed across the country and measured for over 15years by the PNG Forest Research Institute (PNGFRI). We analysed data from 84 of these plots in harvested forest to examine temporal trends in stand condition following harvesting. Mortality rates were investigated in 10 of the 21 plots in harvested forest that were burned during the 1997-98 El Nino drought with sufficient data for analyses. We tested a model developed in Queensland tropical forests to determine whether or not a critical threshold residual BA existed for the recovery of harvested tropical forests in PNG. Results from a logarithmic regression analysis of the relationship between starting BA (BA at first census) and stand BA increment after selective harvesting showed a positive increase in BA growth (r2=0.74, p<0.05). However, there was no critical threshold in residual BA that determined whether a harvested forest was likely to degrade or recover BA growth after harvesting. Our analyses suggested that the response to harvesting was variable, with the majority of un-burned plots (75%) showing an increase in BA and remainder a decrease. Average BA of selectively-harvested tropical forests was about 17m2ha-1±4.17 (SD). Average annual increment in BA across the 84 un-burned plots was 0.17m2ha-1year-1±0.62 (SD). Thus these forests generally show capacity to recover after selective harvesting even when the residual BA is low. A proportion of the BA increment is made up of non-commercial pioneer species that originate in significant gaps after harvesting. On burned plots, BA is affected by high mortality rates. The fate of these forests will depend on the degree of future harvesting, potential conversion to agriculture and the impact of fire and other disturbances. © 2011 Elsevier B.V. Source


Lu Z.,University of Utah | Van Wagoner R.M.,University of Utah | Pond C.D.,University of Utah | Pole A.R.,University of Utah | And 7 more authors.
Organic Letters | Year: 2014

An antimalarial screen for plants collected from Papua New Guinea identified an extract of Horsf ieldia spicata as having activity. Isolation of the active constituents led to the identification of two new compounds: myristicyclins A (1) and B (2). Both compounds are procyanidin-like congeners of myristinins lacking a pendant aromatic ring. Myristicyclin A was found to inhibit the ring, trophozoite, and schizont stages of Plasmodium falciparum at similar concentrations in the mid-μM range.© 2013 American Chemical Society. Source


Dawson J.,Coral Cay Conservation | Turner C.,Jaquelin Fisher Associates | Pileng O.,Coral Cay Conservation | Pileng O.,Walindi Nature Center | And 5 more authors.
Australian Mammalogy | Year: 2012

From June 2007 to February 2009 the Waria Valley Community Conservation and Sustainable Livelihoods Project completed a mist net survey of bats in the lower Waria Valley, Morobe Province, Papua New Guinea. The Waria Valley is located on the north coast of the Morobe Province ∼190km south-east of Lae, and still has large tracts of intact lowland hill and plain rainforest. Four broad habitats (agricultural, secondary forest edge, primary forest edge and primary forest) were surveyed using mist nets. A total of 596 individuals representing 11 species were caught, measured and identified over 8824 net-m h-1 across 99 nights. Within the limitations of this method, primary forest edge sites in general showed the highest degree of species richness and diversity and along with secondary forest edge sites were more even in species composition. Primary forest and agricultural sites were each dominated by a single species, Syconycteris australis and Macroglossus minimus respectively. Most captures were megachiropterans and microchiropterans were underrepresented, presumably in part because of the survey method employed. Journal compilation © Australian Mammal Society 2012. Source


Fox J.C.,University of Melbourne | Vieilledent G.,CIRAD - Agricultural Research for Development | Yosi C.K.,University of Melbourne | Yosi C.K.,Papua New Guinea Forest Research Institute | And 2 more authors.
Ecosystems | Year: 2011

Assessment of forest carbon (C) stock and sequestration and the influence of forest harvesting and climatic variations are important issues in global forest ecology. Quantitative studies of the C balance of tropical forests, such as those in Papua New Guinea (PNG), are also required for forest-based climate change mitigation initiatives. We develop a hierarchical Bayesian model (HBM) of aboveground forest C stock and sequestration in primary, selectively harvested, and El Niño Southern Oscillation (ENSO)-effected lowland tropical forest from 15 years of Permanent Sample Plot (PSP) census data for PNG consisting of 121 plots in selectively harvested forest, and 35 plots in primary forest. Model parameters indicated: C stock in aboveground live biomass (AGLB) of 137 ± 9 (95% confidence interval (CI)) MgC ha-1 in primary forest, compared with 62 ± 18 MgC ha-1 for selectively harvested forest (55% difference); C sequestration in primary forest of 0. 23 ± 1. 70 MgC ha-1 y-1, which was lower than in selectively harvested forest, 1. 12 ± 3. 41 MgC ha-1 y-1; ENSO-induced fire resulted in significant C emissions (-6. 87 ± 3. 94 MgC ha-1 y-1). High variability between PSPs in C stock and C sequestration rates necessitated random plot effects for both stock and sequestration. The HBM approach allowed inclusion of hierarchical autocorrelation, providing valid CIs on model parameters and efficient estimation. The HBM model has provided quantitative insights on the C balance of PNG's forests that can be used as inputs for climate change mitigation initiatives. © 2011 Springer Science+Business Media, LLC. Source

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