Graeme P. Berlyn - US grants

A collaborative research project will be conducted by the University of Washington, Yale University, and Oregon State University for an experimental study of ecosystem responses to tree-fall gaps and spatial and temporal relationship between above- and belowground gaps. It is hypothesized that mechanisms of community and ecosystem responses to gaps can only be understood if both above- and belowground structures and resources are considered. An experiment to determine the size of aboveground gap needed to form a belowground gap in mature and old-growth coniferous forests will be imposed. The investigators will also measure how above-and belowground structural changes are reflected in resource availability and loss and in vegetative response. To examine the hypotheses, the team will create tree- fall gaps of ranging from small to large in five sizes (0, 2, 8 and 16 and 32 trees removed) in reach of two stand developmental stages: mature (understory reinitiation), and old growth. Above and belowground sampling will be conducted to provide an estimate of the mean of the gap and will consist of root biomass (separated into tree, shrub and herb components), N leaching below the rooting zone, and soil temperature and moisture, light level determinations, shrub and herb biomass, seed germination and monitoring of advanced regeneration. In the old-growth stands, above-and belowground resources (plus net N mineralization) and vegetative biomass will be sampled more intensively to provide not only an estimate of the gap mean but of the within-gap spatial patterns. In addition, trenching experiments will be established in the old-growth stands to test the relative importance of above- and belowground resources on tree establishment and growth and develop predictive models of plant response to resources. The three-institution project team is excellent. Research sites and facilities are first rate. Results should be important to both the fundamental understanding of forest ecology and to forest resource management.

0337134
Anisfeld

This grant provides partial support for the acquisition of a Carbon-Nitrogen-Sulfur(CNS) analyzer for solid samples. This instrument would replace an antiquated CHN analyzer in the School of Forestry and Environmental Studies at Yale University which is no longer operable. The CHN would support research and education in fields spanning disciplines of forestry, soil science and marine chemistry. Specific examples of research uses of the CHN will include:

o measurement of C and N content of salt marsh sediment and vegetation in order to
understand marsh accretion and loss processes and their implications for coastal water quality

o measurement of S content of riverine suspended sediment in order to better understand the S cycle in oxygenated surface waters and its impact on trace metal speciation

o measurement of C and N content of riverine suspended sediment to supplement isotopic
studies aimed at understanding sources and bioavailability of particulate organic carbon

o measurement of C and N content of soil and plant material (including woody tissue) in order to assess the effects of changing nutrient status at the Hubbard Brook Experimental Forest

o measurement of foliage N content in order to understand the ecological and physiological controls on seedling development and tree health

o measurement of C and N content of tropical forest soils and vegetation in order to assess C sequestration in these ecosystems.
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1438564 (Felson). Green walls provide benefits that have fostered the growth of a new industry as they can passively moderate exterior wall surface temperatures and thereby reduce building heating and cooling loads, attenuate surface temperature variations and solar exposure that degrade exterior wall finishes, and provide ecosystem service benefits including air pollution and particulate removal, mitigation of urban heat island effects, and urban wildlife habitats. To date, these benefits do not offset the costs of green walls, and therefore, the market for green walls remains limited. This research will address problems that must be resolved to transform existing green wall technology into an active technology for process heat rejection (i.e., principally, here, for chilled water generation), and thereby expand the market to a wide range of applications from households to institutions and industry. The objective is to provide a sustainable alternative to wet cooling tower technology that maintains the benefits of existing green walls, employing their methods of construction and operation, while avoiding the shortcomings of wet cooling tower technologies (i.e., single use and contamination of cooling water).

The investigators are targeting the creation of a green wall heat rejection technology with integrated water biofiltration capabilities and a mathematical transport model to simulate the thermal and biofiltration performance of the technology for experimental and design purposes. The performance of these "thermoGreenWallTM" (tGW) systems will be investigated through coordinated experimental and modeling methods using lab-scale tGW panels and full-scale prototypes and a tanks-in-series model developed by the PIs. The lab-scale tGW panels will be constructed as mesocosm experiments to systematically investigate plant/substrate compatibility/productivity (e.g., using a root area meter and destructive sampling for root biomass determination), plant health (e.g., using chlorophyll fluorescence), water biofiltration methods, performance, and interaction with plant/substrate systems, and heat rejection transport mechanisms and performance.