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A novel in situ optical sensor for measuring spectral irradiances and beam attenuation was evaluated. During laboratory calibrations, the instrument performance was found to be stable, with a wavelength resolution of ~5nm and linear radiometric response over the range of irradiances expected in natural waters. However, the angular response of the irradiance sensors was not ideal, resulting in errors of up to ±50% in the irradiance magnitude, which could not be systematically corrected. Radiative transfer modelling of a subset of the data measured in Baltic waters showed that the relative spectral information was not significantly affected by these errors, and data analyses were restricted to investigating spectral features. Data were collected in optically diverse waters in the Baltic Sea, the N.W. Atlantic Ocean, the Mediterranean Sea and in the River Hamble, UK. Spectral signatures similar to those of phytoplankton pigments, coloured dissolved organic matter (gelbstoff) and inorganic sediments were observed in reflectances from the Mediterranean, Baltic and Southampton Water respectively. New spectral values of the downwelling diffuse attenuation coefficient, Kd(λ), are presented, corresponding to mean 1% light level depths at 550nm ranging between 5m in the Baltic and >80m in the Mediterranean. Algorithms based on reflectance ratios for retrieving chlorophyll-a concentrations were tested for a variety of wavelength bands used in existing or historical satellite sensors. Narrow bands (±5nm or less) located as for the German sensor MOS and the American sensor MoDIS were found to perform best for the range of waters studied. Reflectance ratios for 443:615 or 530:665 gave the best correlations with chlorophyll-a for a dataset from Baltic and Atlantic waters (r²=0.7, n=70), and significant correlations between absorption by gelbstoff and the reflectance ratio 443:530 were found. The fourth derivative of reflectance spectra showed that particular spectral features appeared consistently in data from optically diverse waters. The reflectance data were used to calculate absorption spectra using a simple reflectance model and these spectra were deconvolved into a series of Gaussian bands. Multiple regressions between band areas and pigments resulted in significant correlations with several taxonomic marker pigments, including chl-b, zeaxanthin and β-carotene. Absorption by gelbstoff was found to be well correlated with a Gaussian band centred in the near UV. These results indicate that in situ or above water measurements of reflectance, at sufficiently high spectral resolution, may be used to monitor phytoplankton succession patterns as well as gelbstoff.

Adolescence is a crucial life stage involving aspects of identity development and decision-making that have potential life-long consequences. Researchers have found that a sense of meaning and purpose is related to a number of beneficial factors during adolescence, including resilience, healthy self-esteem, academic engagement, and overall well-being. Spirituality is a main avenue through which many individuals find a sense of meaning and purpose and may be one of the mediating factors between adolescent meaning-making and well-being. Despite this knowledge, there is a lack of research involving the use of meaning-based counseling in the schools. There is also evidence that students are discouraged from exploring or expressing their spiritual beliefs and questions in the school setting. This qualitative interview study was designed to investigate middle school counselors' perspectives and practices in regard to exploring meaning and spirituality with their adolescent students. Analysis of ten individual interviews and a focus group revealed that the school counselor participants did believe it was important to work with students around meaning and did so primarily through the overarching theme of identity. Interviewees described how they supported students with many aspects of meaning and identity exploration through avenues such as their suffering and challenging circumstances, behavior and choices, and connections with others and things they care about. Spirituality, however, was an aspect of students' identities that participants reported avoiding in their work with adolescents in the schools. Analysis of participants' perspectives suggested that avoidance of this area was due to the participants' own identities as public school employees, fear of perceived repercussions, and connotations with the risk of imposing their own values. Practical implications for both school counselors and counselor educators, as well as directions for future research, are addressed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]