Evaluating Rice Straw as a Substitute for Barley Straw in Inhibiting Algal Growth in Farm Ponds

Algal blooms disrupt aquatic ecosystems and are more common in lakes, ponds, and rivers during the summer months due to nutrient pollution. Livestock production can contribute increased quantities of nutrients to water bodies from runoff of manure. Commonly used mechanical and chemical control methods may have limited success because algae are small and propagate quickly. Barley (Hordeum vulgare) straw has been shown to inhibit the growth of algae as the straw decomposes aerobically in ponds. Therefore, barley represents a natural option for algal biomass control. However, the small amount of barley production in Arkansas limits the availability of barley straw as a solution to control algal blooms locally. Other cereal grain straws may produce similar inhibitory effects during decomposition. Rice (Oryza sativa) is produced in large quantities in Arkansas, making rice straw a locally sourced straw product. The objective of this research was to determine the efficacy of using rice compared to barley straw to inhibit algal growth in freshwater ponds. Data were collected from nine farm ponds, three treated with rice straw, three treated with barley straw, and three without amendment to serve as the experimental control. Dissolved oxygen, pH, nitrate-nitrogen (NO3--N), dissolved phosphorus (P), temperature, and turbidity were measured for 14 weeks from June 12 to September 17, 2018. Algal biomass was measured as chlorophyll-a concentration to evaluate treatment effectiveness over time. Dissolved oxygen was significantly influenced by treatment and time. The NO3--N concentration in ponds treated with rice straw was significantly greater than the control and barley treatment. Chlorophyll-a concentrations were variable, and there were no consistent trends through time within a treatment. More research under controlled conditions to understand impacts of abiotic conditions, microbial and algal community compositions, and mode of action of algal inhibition is required before cereal straw can be a reliable, locally sourced method of algal control in farm ponds

Evaluation of Turbidity Reduction Using Polyacrylamide with Linear Sediment Control Best Management Practices

Accelerated erosion and highly turbid stormwater runoff from construction sites are known to cause a variety of environmental and economic problems. To reduce turbidity and keep eroded sediment on site, this research was conducted to evaluate the potential for turbidity reduction using polyacrylamide (PAM) flocculants with sediment control best management practices (BMPs). Previous research has shown significant turbidity reduction when applying granular PAM to linear sediment control BMPs. Numerous studies indicate that PAM loses efficacy if it becomes wet and then dries. This makes PAM reapplication a necessary part of maintaining sediment control BMPs using PAM and suggests that further research is warranted. The longevity of PAM when it is applied and reapplied to sediment tube ditch checks was evaluated. No statistical differences were observed between freshly applied PAM and PAM which endured a three-, five-, or ten-day waiting time between reapplication and runoff event. However, the two trials of the ten-day test yielded the highest effluent turbidities that were observed. Research on a South Carolina Department of Transportiation (SCDOT) construction site analyzed the impact on turbidity of rock ditch checks (RDCs) and rock ditch checks with washed #57 stone on the upstream face (RDC-WS), both with and without granular PAM. It was observed that RDCs alone tended to increase turbidity of runoff between 116% and 282%. For RDC-WS the observed increase to turbidity was smaller, between 3% and 43%. Both types of check were treated with 100 grams of granular Applied Polymer Systems Silt Stop® #705 PAM and turbidity reduction of runoff was consistently observed, though it varied between 12% and 67% for average turbidity and between 46% and 82% for peak turbidity. Based on these results, when PAM is used with sediment control BMPs, it should be reapplied after every rain event of 0.5 inches or greater, or every 5 days if no such event occurs. This should ensure effective PAM is constantly present to reduce turbidity of runoff during a storm event

Perceived Effects of Peer Observation on Collaboration between Teachers at a Minnesota High School

This study examined teacher perceptions of the effectiveness of a newly implemented peer observation program in a central Minnesota High School. The two research questions for this study were: (1) To what extent do teachers perceive the overall effectiveness of participating in a peer observation process? and (2) To what extent do teachers perceive the overall quality of their professional interactions, communications, feedback, or discussions [with or from or by] peers as a result of participating in this process? A mixed-methods approach was used to gather data in the form of survey and interview responses. A 28-item questionnaire was developed, consisting of a demographic item concerning the roles held in peer observation, 24 Likert-scale items, and three optional open-ended items. An interview protocol was developed to gather description of the teachers’ perception. The population of approximately 100 teachers at this high school were surveyed using the questionnaire. Five Interview participants were selected using criterion sampling techniques. The data for this study was collected during the spring of the 2015-2016 school year. At the time of the study, the peer observation program was in its first year of implementation. The survey results were analyzed using basic descriptive statistics and the interview responses were coded using thematic analysis to help answer the research questions. The results from the survey and interviews indicate that the peer observation process is an effective form of professional development. In addition, participants indicate that the professional interactions and collaborative conversation have improved from taking part in the peer observation process. The participants noted the benefits of taking part in peer observation were the opportunity to critically reflect, the increased self-awareness of their teaching practice, and collaborating with their peers. The main challenge for teachers was the additional time needed to take part in the process