Treesearch

Recovering populations often must meet specific growth rate or abundance targets before their legal status can be changed from endangered or threatened. While the efficacy, power, and performance of population metrics to infer trends in declining populations has received considerable attention, how these same metrics perform when populations are increasing is less clear. We examined the ability of a one-sample effective population size (Ne) estimator (LDNe) to discriminate between stable and increasing population trends across varying sample and initial population sizes. The performance of...

Changing climatic conditions and an abundance of dense, mature pine forests have helped to spur an epidemic of mountain pine beetles larger than any in recorded history. Millions of forested acres have been heavily impacted and have experienced extreme rates of tree mortality. This has raised concerns among many people that the death, desiccation, and decomposition of the overstory could have dramatic and negative consequences for affected ecosystems. Compromised water quality, increased fire danger, and losses in timber production are among the primary concerns of what could lie ahead for...

Evaluating the risks of wildfire relative to the valuable resources found in any managed landscape requires an interdisciplinary approach. Researchers at the Rocky Mountain Research Station and Western Wildland Threat Assessment Center developed such a process, using a combination of techniques rooted in fire modeling and ecology, economics, decision sciences, and the human dimensions of managing natural resources. The method combines predictive mapping of the distribution and intensity of wildfire with locations of highly valued resources. By soliciting input from experts, the response of...

The extent and distribution of global forests is a matter of considerable concern. The overall rate of deforestation remains high although recent reports suggest it is fi nally beginning to decline (FAO 2011 ) . But this hides regional differences. In temperate regions net forest cover is increasing because of afforestation and natural expansion of forests. By contrast, net forest cover in most tropical regions continues to decline and few of the remaining forests are being managed on a sustainable basis (Asner et al. 2010 ; Foley et al. 2005 ) . This means that more and more tropical...

Recent estimates by the World Conservation Union (IUCN) and World Resources Institute (WRI) suggest that over 2 billion ha of forests are degraded and in need of restoration. Goren Persson, former prime minister of Sweden, proposed the formation of a Global Restoration council to implement the Bonn Challenge to restore 150 million ha of degraded forests by 2020. The importance of forest land cover to climate change mitigation is reflected in international efforts to Reduce Emissions from Deforestation and Degradation (REDD+) of tropical forests, while at the same time enhancing biodiversity...

Bamboo was a kind of biomass materials and had great potential as a bio-energy resource of the future in China. The physical and combustion properties of bamboo pellets were determined and the effects of moisture content (MC) and sizes of particle on these properties were investigated in this research. The results showed that MC and sizes of particle affected these properties of bamboo pellets. The effects of MC on physical properties including length, diameter, pellet MC, unit density, bulk density were significant at p=0.05. But there were not significantly difference between particle...

Bamboo is a potential lignocellulosic biomass for the production of bioethanol because of its high cellulose and hemicelluloses content. In this research, ethanosolv pretreatment catalyzed by sulfuric acid was studied in order to enhance enzymatic saccharification of moso bamboo. The addition of 2% (w/w on bamboo) sulfuric acid in water or 75% (v/v) ethanol was demonstrated effective in pretreatment and fractionation of bamboo. The ethanosolv pretreatment yielded a solid fraction with 84.5% cellulose. The cellulose-to-glucose conversion yields were 77.1% (ethanosolv) and 57.3%(water) after...

Bamboo, with its advantages of fast growth, short renovation, easy propagation and rich in cellulose and hemicellulose, is a potential feedstock for bioethanol or other biofuels production. The objective of this study was to examine the fea- sibility of microwave assistant KOH pretreatments to enhance enzymatic hydrolysis of bamboo. Pretreatment was car- ried out by immersing the bamboo in KOH (12% and 8% w/w bamboo) solutions and exposing the slurry to microwave radiation power of 400 W for 30min. Chemical composition of the pretreated substrates and spent liquor was analyzed. Pretreated...

In a unique way, IRENI (Infrared environmental Imaging), operated at the Synchrotron Radiation Center in Madison, combines IR spectroscopy and IR imaging, revealing the chemical morphology of a sample. Most storage ring based IR confocal microscopes have to overcome a trade-off between spatial resolution versus signal-to-noise ratio (SNR). For IRENI, this problem has been addressed by introducing a beam-matrix that is comprised of 3x4 IR-beams, generated from the fan of a bending magnet extracted over a range of 320x27mrad2 by employing a set of suitable mirrors, see Fig. 1 [1].

How does a highly degraded Hawaiian tropical dry lowland ecosystem dominated by the non-native invasive Megathyrsus maximus (guinea grass) respond to different restoration treatments (three native species outplanting treatments; four native broadcast seed treatments)? What effect do restoration treatments have on invasive and native species groundcover, biomass and physiological activity, and volumetric soil water content? The study was performed at Waianae Kai Forest Reserve, Island of Oahu, Hawaii, USA. The invasive grass M. maximus was suppressed by initial mowing and pre- and post-plant...