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Full-Text Articles in Life Sciences

Spruce Budworm Defoliation Dynamics And Its Influence On The Acadian Forest, Cen Chen Dec 2019

Spruce Budworm Defoliation Dynamics And Its Influence On The Acadian Forest, Cen Chen

Electronic Theses and Dissertations

Spruce budworm (SBW; Choristoneura fumiferana (Clem.)) is the primary forest defoliator in North America. SBW defoliation has affected tens of millions ha of forests during its periodic outbreaks and caused severe growth reduction and mortality of spruce-fir (Picea-Abies) species. Evaluating these damaging effects of SBW defoliation requires understandings of the variation and dynamics of defoliation, as well as trees' variable responses to defoliation in consideration of various tree- stand-, and site-level factors. In this dissertation, we developed statistical models to 1) evaluate influences of SBW defoliation on spruce-fir stand dynamics of annual volume net growth, mortality, …


Comparing Independent Approaches To Estimate Age At Size Of The Jonah Crab (Cancer Borealis): Corroborating Gastric Mill Band Counts As A Direct Aging Method, Carlton Huntsberger Aug 2019

Comparing Independent Approaches To Estimate Age At Size Of The Jonah Crab (Cancer Borealis): Corroborating Gastric Mill Band Counts As A Direct Aging Method, Carlton Huntsberger

Electronic Theses and Dissertations

Knowing the age of an organism is essential in understanding the dynamics and management of wild populations. Age determination has been an especially long-standing challenge in the study of crustaceans, since they posed a unique challenge, shedding all calcified structures with each molt. The Jonah crab (Cancer borealis), is one of many commercially harvested crustaceans for which no absolute aging method has yet been established. It is an ecologically important species and a newly managed fishery in New England and Atlantic Canada. The recent increase of commercial fisheries for this species has highlighted the large data gap of …


Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley May 2016

Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley

Electronic Theses and Dissertations

Rainbow Smelt (Osmerus mordax) are an important fish distributed throughout northeastern North America with both anadromous and landlocked populations. Abundance, size at age, and maximum size vary widely among populations and life histories. In order to compare anadromous and landlocked populations, we collected spawning adults in 2014 from four anadromous and three landlocked populations. Scales and otoliths from the anadromous fish were examined and compared for estimates of bias and precision in ageing. Analysis of both scales and otoliths provided age estimates that were acceptable, but estimates from scales were more precise and had less bias. Otoliths were …


Developmental Cis-Regulatory Analysis Of The Cyclin D Gene In The Sea Urchin Strongylocentrotus Purpuratus, Christopher Michael Mccarty Aug 2014

Developmental Cis-Regulatory Analysis Of The Cyclin D Gene In The Sea Urchin Strongylocentrotus Purpuratus, Christopher Michael Mccarty

Electronic Theses and Dissertations

Proper execution of animal development requires that it be integrated with cell division. In part, this is made possible due to cell cycle regulatory genes becoming dependent upon developmental signaling pathways that regulate their transcription. Cyclin D genes are important bridges linking the regulation of the cell cycle to development because these genes regulate the cell cycle, growth and differentiation in response to intercellular signaling. In this dissertation, a cis-regulatory analysis of a cyclin D gene, Sp-CycD, in the sea urchin, Strongylocentrotus purpuratus, is presented. While the promoters of vertebrate cyclin D genes have been analyzed, the cis-regulatory sequences across …


The Growth, Yield, And Financial Performance Of Isolated Eastern White Pine (Pinus Strobus L.) Reserve Trees, Christopher E. Zellers Aug 2010

The Growth, Yield, And Financial Performance Of Isolated Eastern White Pine (Pinus Strobus L.) Reserve Trees, Christopher E. Zellers

Electronic Theses and Dissertations

The ability of eastern white pine (Pinus strobus L.) to persist as emergent trees makes this species well suited to silvicultural systems in which they are retained as isolated reserves after a regeneration harvest. While such systems are implemented throughout the Acadian spruce-fir region of Maine, little is known about the growth response and financial performance of eastern white pine following complete release from competition. In this study, 77 trees from 8 sites throughout the Acadian spruce-fir region were sampled tree and crown measurements, and increment cores were extracted at breast height, as well as from the top of …