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This study examined the association of air, land, and water variables with the first historical occurrence and current distribution of toxic Prymnesium parvum blooms in reservoirs of the Brazos River and Colorado River, Texas (USA). One impacted and one reference reservoir were selected per basin. Land cover and use variables were estimated for the whole watershed (WW) and a 0.5-km zone on either side of streams (near field, NF). Variables were expressed in annual values. Principal component and trend analyses were used to determine (1) differences in environmental conditions before and after the 2001 onset of toxic blooms in impacted reservoirs (study period, 1992-2017), and (2) traits that uniquely discriminate impacted from reference reservoirs (2001-2017). Of thirty-three variables examined, two positively aligned with the reoccurring appearance of blooms in impacted reservoirs (air CO

Environmental and ecological degradation has raised concerns worldwide. Negative attitudes toward the environment plus disinterest have led to improper behavior, influencing climate change and global warming. Awareness could have a positive environmental impact by influencing attitudes and behaviors. One way to generate awareness and ensure positive behavior is through education. Using the Theory of Reasoned Action (TRA), a 33-questions survey was implemented to college students from Texas, Louisiana, and Honduras to (1) compare students’ environmental attitudes, behaviors, and subjective norms at the three universities; and (2) predict how much of the undergraduate students’ environmental behavior variance could be explained by their environmental attitude, subjective norms, and perceived environmental knowledge. Multivariate analysis of variance and hierarchical regressions were performed to address the objectives, respectively. Results showed that Honduras and Louisiana students’ environmental attitudes, behavior, and subjective norms are significantly different than Texas students, and TRA variables increased the prediction of behavior variance by 15%. Understanding interactions between behavior, attitude, knowledge, and subjective norms among college students from different universities may help assess environmental interventions and design successful programs based on group needs.

The Jim Bertram Lake System consists of several stream impoundments within the City of Lubbock, Texas (USA). Baseflow in the upstream reach is dominated by nitrogen-rich-treated wastewater. While toxic blooms of Prymnesium parvum have occurred in this system for ∼2 decades during fall or winter-spring, little is known about water quality variables that facilitate blooms or the alga’s spatiotemporal distribution. Water quality associations were examined monthly over a 1-year period. Total phosphorus was largely below the detection limit, suggesting that the system is phosphorus limited. Algal abundance was low during the assessment period and associations were determined using multiple logistic regression. Algal incidence was negatively associated with temperature and positively with organic nitrogen and calcium hardness. These findings conform with earlier reports but positive associations with the latter two variables are noteworthy because they have not been widely confirmed. Spatiotemporal distribution was evaluated in fall and winter-spring of three consecutive years. Prymnesium parvum incidence was higher in the upper than in the lower reach, and detections in the lower reach occurred only after a dense bloom developed in the upper reach contemporaneously with stormwater runoff-associated flooding. Thus, the upstream reach is a major source of propagules for downstream sites. Because urban runoff is a source of phosphorus and its nitrogen: phosphorus ratio is lower than prevailing ratios in the upper reach, what triggered the bloom was likely relief from phosphorus limitation. This study provided water quality, geographic and hydrological indices that may inform prevention and control methods for harmful algae in nitrogen-enriched urban systems.