Time filter

Source Type

of Minnesota, Minnesota, United States

McLauchlan K.K.,Kansas State University | Williams J.J.,Kansas State University | Engstrom D.R.,Science Museum of Minnesota
Holocene | Year: 2013

Transfer of nutrients from terrestrial to aquatic ecosystems is a natural process with climatic, biotic, and geologic controls. Recently, increasing concern about human manipulation of global nutrient cycles has required a long-term approach to assessing the nutrient status of aquatic systems. Data available in palaeorecords can assess current trophic status, baseline conditions, and long-term processes controlling nutrient fluxes on decadal to millennial timescales. Here, we review three palaeolimnological methods used to reconstruct nutrient cycling: (1) chemical compounds preserved in lacustrine sediment, (2) aquatic biotic indicators (often using a quantitative transfer function), and (3) quantitative empirical sediment flux estimates. The millennial-scale regulation of nutrient cycling by climate and catchment geochemistry leads to a gradual trajectory of dystrophication over the Holocene in many temperate lakes. In many systems, the magnitude of recent anthropogenic changes to nutrient cycling is large compared with natural fluctuations, but this perspective could also be due to the selection of study sites that are currently experiencing eutrophication. Increased nutrient loading to aquatic systems is not always accompanied by decreased ecosystem function. The powerful temporal perspective from palaeolimnology can be complemented with modern mechanistic approaches to lead to increased understanding of the rates, patterns, and mechanisms of nutrient fluxes. © The Author(s) 2013.

Wigdahl C.R.,University of Maine, United States | Saros J.E.,University of Maine, United States | Fritz S.C.,University of Nebraska - Lincoln | Stone J.R.,Indiana State University | Engstrom D.R.,Science Museum of Minnesota
Holocene | Year: 2014

Sedimentary diatom profiles from saline lakes are frequently used to reconstruct lakewater salinity as an indicator of drought. However, diatom-inferred salinity (DI-salinity) reconstructions from geographically proximal sites in the Great Plains (USA) have yielded disparate results. This study explores how physical changes in lake habitat resulting from drought may affect climate inferences from salinity reconstructions. Differences in relationships among drought, lake-level change, and diatom community structure over the last century were examined for three saline lakes in the northern Great Plains with dissimilar DI-salinity records. At each site, models were developed relating available planktic:benthic (P:B) habitat area to lake-level change, and models were compared with instrumental drought records and fossil diatoms to understand how drought conditions were recorded in sedimentary diatom assemblages. The degree to which DI-salinity tracked drought variation was affected by site-specific physical characteristics that influenced the relationship between lake-level change and P:B habitat zonation within each lake. Moon Lake showed the strongest correlation between drought and DI-salinity, although this relationship was weaker during wetter conditions, as highstands resulted in a larger influx of benthic diatoms. At Coldwater Lake, a dual-basin system, P:B varied depending on lake level, which apparently reduced the correlation between DI-salinity and drought. At Lake Cochrane, the simplest and freshest of the three basins, the P:B of fossil diatoms was a better proxy for drought than DI-salinity. The integration of additional ecological characteristics into interpretations of paleoclimate records, particularly for biologically-based proxies, may improve reconstructions of regional patterns of climate variation. © The Author(s) 2014.

Agency: NSF | Branch: Continuing grant | Program: | Phase: RES ON GENDER IN SCI & ENGINE | Award Amount: 2.81M | Year: 2011

The Science Museum of Minnesota (SMM) proposes to develop an extension service project, Peer Alliance for Gender Equity (PAGE) Extension Service, that will build the capacity of district education leaders in Science, Technology, Engineering, and Mathematics (STEM) to provide professional development (PD) to K-12 STEM teachers in research-based, gender-sensitive pedagogical classroom practices. These K-12 district leaders will serve as Extension Service Agents (ESAs) in the Upper Midwestern United States to implement a unified program of change focused on gender equity in STEM education that integrates theory, research findings, and practice. Each ESA will participate in 80 hours of PD through a PAGE Institute, Colloquia, a Virtual Learning Network (VLN), and Symposium over a 12-month period. The PAGE Portfolio of research, methods, and strategies will be used throughout the program. The goals of the PAGE Extension Service are to (1) prepare district-based, K-12 PD leaders to serve as ESAs for gender equity in STEM education by engaging them in summer institutes that provide a coherent foundation in related theory, pedagogical practices, and belief systems (referred to as the PAGE Portfolio); (2) develop ESAs ability to adapt, incorporate, and refine PAGE Portfolio modules within their own PD services for K-12 teachers through colloquia and on-going consultation; and (3) promote educational researcher awareness of the challenges and successes that teachers encounter as they ground their practice in theory by creating feedback loops among researchers, the Expert Project Team, ESAs, and teacher practitioners.

Intellectual Merit: PAGE will create a new model of extension services incorporating best practices from the PD literature that approaches gender equity in the context of complex equity issues of race, culture, and class, and is highly sensitive to the needs and pragmatic concerns of K-12 district leaderships who rarely are offered intensive professional development specifically designed for their positions. The field-tested PAGE Portfolio is organized around four major themes: (1) Equity and Access, focusing on classroom interaction patterns and pipeline issues; (2) Curriculum and Pedagogy, focusing on gender sensitive pedagogy and curriculum; (3) Reconstructing the Nature and Culture of STEM, focusing on the epistemology of these disciplines and the ways in which the values and beliefs behind scientific knowledge production have been associated with the masculine; and (4) Identity, focusing on the relationship between students identity formation and learning in STEM classrooms.

Broader Impact: Over five years, PAGE will involve the efforts of 125 ESAs, each of whom provide professional development to a minimum of 50 STEM educators per year. The Practitioner Community upon whom PAGE will ultimately have an impact includes 18,750 K-12 STEM teachers in public schools in Iowa, Minnesota, North Dakota, South Dakota, and Wisconsin. PAGE will bring together strategies that translate research into action through the PAGE community of educators who have extensive aggregate expertise in gender equity, STEM education, PD, research, and evaluation. The capacity built in individuals and programs through PAGE will be sustained through the combination of intensive PD, the virtual and face-to-face consultation, and material support for implementation of modules. The creation of a regional model that is responsive to local, state, and regional contexts and to the complex issues of identity will be disseminated to the national STEM education community and gender equity researchers.

Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 349.79K | Year: 2011

There is a need at NSF and in the field for a set of guidelines that would direct the evaluation process for projects whose purpose is to develop a more diverse STEM workforce. The purpose of this project is to create guidelines that would be used by PIs and proposal developers to write effective evaluation plans in their proposals; by evaluators to plan, implement and conduct rigorous project evaluations; and by Program Officers and reviewers to judge the merits of evaluation sections of proposals or to provide guidance for prospective or current projects. comprehensive guide, population-focused tip sheets, interactive internet materials and a wiki about conducting evaluations with diverse populations including considerations centering on gender, race/ethnicity, and disabilities. Consideration is also given to the setting of the evaluation (e.g., institutional type, program type). The materials will include information about designing, implementing and assess the quality of projects and activities that focus on broaden participation in STEM education, especially those targeting post-high school participants. The final products will be unique because they will specifically address evaluation issues related to diverse populations such as under represented minoritis, females, individuals with disabilities, and individuals in multiple categories.

This project builds on previous NSF-funded work by the PIs individually and together. In addition, several specific NSF-funded or developed documents have led the way in formulating the idea and design for this project. Examples are the Framework for Evaluating Impacts of Broadening Participation Projects: A Report from a National Science Foundation Workshop, co edited by Beatriz Chu Clewell and Norman Fortenberry under Contract Number GS-10F-0482P by the Division of Research on Learning, the Indigenous Evaluation Framework Report by LaFrance and Nichols (Grant 0438720), and the Mixed Methods User-Friendly Handbook which was updated in 2010 (Contract REC 99-12175). The specific objectives of the project delineate the plan for the project, including a needs assessment with stakeholder groups, a literature review, the development and beta testing of materials, revision and field testing, and dissemination. The project includes an Advisory Board that has the expertise to provide important input to the process. The project also includes an external, independent evaluator and an evaluation plan that considers the progress and outcomes of the project.

This project is a unique contribution to the fields of evaluation, broadening participation, and STEM education.

Agency: NSF | Branch: Continuing grant | Program: | Phase: RES ON GENDER IN SCI & ENGINE | Award Amount: 524.72K | Year: 2012

Intellectual Merit: The Science Museum of Minnesota and Purdue Universitys Institute for P-12 Engineering Research and Learning are conducting a study within out-of-school contexts that will explore gender differences in the development of engineering interest and understanding in children between the ages of 4 and 11. During the study, the researchers will closely examine three specific informal environments: a pre-school program where parents and children can engage with engineering focused activity, a family-oriented engineering event for elementary students and their parents, and an engineering exhibit within a science museum. These settings, each featuring a high level of parent-child interaction, have been intentionally chosen due to an emerging trend in engineering education research that identifies the parent as playing a crucial role in girls decisions regarding engineering careers. The project will examine the ways in which engineering practices (such as the iterative design, build, and test cycle) impact the development of interest and understanding. The study focuses on studying children during the critical years before middle school, when girls have been shown to have significantly lower levels of interest in engineering than boys.

Broader Impacts: Investigating the processes by which girls develop early interest and understanding in engineering is essential to addressing the persistent underrepresentation of women in engineering fields. Informal learning experiences, such as interactions in the home, visits to museums, and other everyday encounters, represent a rich array of settings for the development of engineering interest that have been minimally researched. The project will share results from the study through traditional academic channels, and also through parent and practitioner workshops for informal science educators that disseminate useful practices and techniques for engaging girls in engineering at a young age. In addition, the partnership between the Science Museum of Minnesota and Purdue University creates a strong foundation for subsequent collaborative projects focused on researching informal engineering education. The project has the potential to significantly impact the ways in which girls begin to cultivate a lifelong interest in engineering, which may ultimately encourage more women to pursue engineering careers in the future.

Discover hidden collaborations