Forest Sciences Commons^™

Counting Crabs: Assessment Of Mangrove Crab Diversity And Density Among Three Sites In Ushongo, Tanzania, Clarasophia Gust

Independent Study Project (ISP) Collection

This study assessed the density and diversity of crabs across three mangrove forest zones in Ushongo, Tanzania. The aim was to understand variance in the composition and distribution of mangrove crabs in relation to mangrove tree composition gradients in the area. Sites were measured using a 200m line transect and 40-plot method. Data was also collected from a sand beach habitat to compare to the diversity and distribution of mangrove habitats. Diversity was analyzed using Simpson’s Index of Diversity and an ANOVA test on the average number of species found per plot in each site. Density was analyzed using an …

Tropical Cyclones Disrupt The Relationship Between Tree Height And Species Diversity: Comment, Teng-Chiu Lin, Lixin Wang, Chengyang Zheng, Ryan W. Mcewan, Chung-Te Chang, Jyh-Min Chiang, Chung-Hao Chi

Biology Faculty Publications

In a recent report on the patterns of tree species richness in eastern and western North America, Marks et al. (2016) claimed to have identified an operational indicator of environmental harshness (maximum tree height) and concluded that environmental stressors that limit tree height also act as ecological filters on species richness. Marks et al. (2017) attributed the positive association between species richness and maximum tree height to both the direct effects of environmental harshness on species richness and the indirect effects of environmental harshness on species richness as mediated by maximum tree height.

This finding overlooked the fact that many …

A Global Study Of Gpp Focusing On Light-Use Efficiency In A Random Forest Regression Model, Suhua Wei, Chuixiang Yi, Wei Fang, George Hendrey

Publications and Research

Light-use efficiency (LUE) is at the core of mechanistic modeling of global gross primary production (GPP). However, most LUE estimates in global models are satellite based and coarsely measured with emphasis on environmental variables. Others are from eddy covariance towers with much greater spatial and temporal data quality and emphasis on mechanistic processes, but in a limited number of sites. In this study, we conducted a comprehensive global study of tower-based LUE from 237 FLUXNET towers, and scaled up LUEs from in situ tower level to global biome level. We integrated the tower-based LUE estimates with key environmental and biological …

Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman

Chemistry Faculty Publications

Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their …

A Walk On The Wild Side: Disturbance Dynamics And The Conservation And Management Of European Mountain Forest Ecosystems, Dominik Kulakowski, Rupert Seidl, Jan Holeksa, Timo Kuuluvainen, Thomas A. Nagel, Momchil Panayotov, Miroslav Svoboda, Simon Thorn, Giorgio Vacchiano, Cathy Whitlock, Thomas Wohlgemuth, Peter Bebi

Geography

Mountain forests are among the most important ecosystems in Europe as they support numerous ecological, hydrological, climatic, social, and economic functions. They are unique relatively natural ecosystems consisting of long-lived species in an otherwise densely populated human landscape. Despite this, centuries of intensive forest management in many of these forests have eclipsed evidence of natural processes, especially the role of disturbances in long-term forest dynamics. Recent trends of land abandonment and establishment of protected forests have coincided with a growing interest in managing forests in more natural states. At the same time, the importance of past disturbances highlighted in an …

Is Initial Post-Disturbance Regeneration Indicative Of Longer-Term Trajectories?, Nathan S. Gill, Daniel Jarvis, Thomas T. Veblen, Steward T.A. Pickett, Dominik Kulakowski

Geography

The ability to estimate and model future vegetation dynamics is a central focus of contemporary ecology and is essential for understanding future ecological trajectories. It is therefore critical to understand when the influence of initial post-disturbance regeneration versus stochastic processes dominates long-term post-disturbance ecological processes. Often, conclusions about post-disturbance dynamics are based upon initial regeneration in the years immediately after disturbances. However, the degree to which initial post-disturbance regeneration indicates longer-term trends is likely to be contingent on the types, intensities, and combinations of disturbances, as well as pre-disturbance ecosystem structure and composition. Our relatively limited understanding of why initial …

Reconstructing Coastal Forest Retreat And Marsh Migration Response To Historical Sea Level Rise, Nathalie Schieder

Dissertations, Theses, and Masters Projects

Climate change assessments predict that rates of relative sea level rise will increase in the future, leading to enhanced inundation of low-lying coastal regions and a 20 – 50 % decline in salt marsh area by 2100. Global sea level rise began accelerating in the late 19th to early 20th century, and local rates along the U.S. mid-Atlantic coast are twice as fast as global estimates. Frequent flooding and salt stress associated with sea level rise lead to coastal transgression, and the survival of ecosystems depends on their ability to migrate inland faster than they erode and submerge. Here, I …

Quantifying Tree Response To Alterations In Pollution Deposition And Climate Change In The Northeastern Us, Alexandra M. Kosiba

Graduate College Dissertations and Theses

Understanding tree physiological responses to climate change is critical for quantifying forest carbon, predicting species' range change, and forecasting growth trajectories. Continued increases in temperature could push trees into conditions to which they are ill adapted -- such as decreased depth of winter snow cover, altered water regimes, and a lengthened effective growing season. A complicating factor is that in the northeastern United States, climate change is occurring on a backdrop of acid deposition and land-use change. In this dissertation, I used three studies to investigate the spatiotemporal nuances of resultant tree and sapling physiology to environmental change.

First, I …