Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Phenotypic Leaf Variation In Avicennia Marina In Tropical Australia: Can Discrete Subpopulations Be Recognised In The Field?, Peter Saenger, Lyndon O. Brooks Nov 2010

Phenotypic Leaf Variation In Avicennia Marina In Tropical Australia: Can Discrete Subpopulations Be Recognised In The Field?, Peter Saenger, Lyndon O. Brooks

Dr Lyndon O Brooks

The geographic patterns of phenotypic variation in leaf morphology traits were studied in the mangrove Avicennia marina (Forsk.) Vierh. in tropical Queensland, Australia, to determine whether discrete subpopulations could be recognised in the field. Significant differences in the various leaf characters occurred among the sites, which were not explained by longitude or latitude, nor by inter-site distances. Hierarchical cluster analysis of the estimated site means showed no coherent geographical groupings of the sites, suggesting that site populations do not follow a differentiation by distance model. Principal component analysis showed that site groupings with consistent leaf morphological characteristics could be identified, …


Balancing Limiting Factors & Economic Drivers For Sustainable Midwestern Us Agricultural Residue Feedstock Supplies, Wally W. Wilhelm, J. Richard Hess, Douglas L. Karlen, Jane M. F. Johnson, David J. Muth Jr., John M. Baker, Hero T. Gollany, Jeff M. Novak, Diane E. Scott, Gary E. Varvel Sep 2010

Balancing Limiting Factors & Economic Drivers For Sustainable Midwestern Us Agricultural Residue Feedstock Supplies, Wally W. Wilhelm, J. Richard Hess, Douglas L. Karlen, Jane M. F. Johnson, David J. Muth Jr., John M. Baker, Hero T. Gollany, Jeff M. Novak, Diane E. Scott, Gary E. Varvel

Douglas L Karlen

Advanced biofuels will be developed using cellulosic feedstock rather than grain or oilseed crops that can also be used for food and feed. To be sustainable, these new agronomic production systems must be economically viable without degrading the soil and other natural resources. This review examines six agronomic factors that collectively define many of the limits and opportunities for harvesting crop residue for biofuel feedstock in the midwestern United States. The limiting factors include soil organic carbon, wind and water erosion, plant nutrient balance, soil water and temperature dynamics, soil compaction, and off-site environmental impacts. These are discussed in relationship …


Recent Advances In The Climate Change Biology Literature: Describing The Whole Elephant, A. Townsend Peterson, Shaily Menon, Xingong Li Aug 2010

Recent Advances In The Climate Change Biology Literature: Describing The Whole Elephant, A. Townsend Peterson, Shaily Menon, Xingong Li

Shaily Menon

Climate change biology is seeing a wave of new contributions, which are reviewed herein. Contributions treat shifts in phenology and distribution, and both document past and forecast future effects. However, many of the current wave of contributions are observational and correlational, and few are experimental in nature, and too often a conceptual framework in which to contextualize the results is lacking. An additional gap is the lack of effective cross-linking among areas of research, for example, connection of sea-level rise and climate change implications for distributions of species, or evolutionary adaptation studies with distributional shift studies. Although numerous important contributions …


Land From The Sea: The Mangrove Afforestation Program Of Bangladesh, Peter Saenger, N A. Siddiqi May 2010

Land From The Sea: The Mangrove Afforestation Program Of Bangladesh, Peter Saenger, N A. Siddiqi

Emeritus Professor Peter Saenger

The coastal areas of Bangladesh have a high cyclone frequency. The protection from cyclone damage afforded by the natural mangrove forests of the Sundarbans, led the Forest Department in 1966 to initiate a mangrove afforestation programme. These initial plantings proved highly successful in protecting and stabilizing coastal areas, and led to a large-scale mangrove afforestation initiative. To date, approximately 120 000 ha of mangroves have been planted. Nursery and planting techniques have been developed for the major species, while additional species are still being investigated. As a result of the extensive monospecific plantations, however, outbreaks of two major insect pest …


Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson Apr 2010

Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson

Shaily Menon

Gymnocladus assamicus is a critically endangered tree species endemic to northeastern India. Local inhabitants traditionally used this species for a variety of purposes. However, rapid population declines led to the species being considered extinct, until fieldwork in 2004 to 2007 identified 14 discrete populations of 1 to 7 trees each. To overcome constraints on field surveys imposed by the region’s remoteness and rugged terrain, we targeted areas of further field inventories by estimating the potential distribution of the species. Ecological niche modeling enabled us to identify 26 sites which the model predicted to be highly suitable for the species’ occurrence. …