Population Characteristics of Ozark Bass (<i>Ambloplites constellatus</i>) in the Upper White River Basin of Northern Arkansas

Ozark Bass (Ambloplites constellatus) is an understudied, endemic fish species in the Upper White River Basin of northern Arkansas. This study was part of an effort by fisheries managers to gather baseline data about the Ozark Bass to aid in understanding population dynamics and contribute to the limited data available for use in determining the efficacy of harvest regulations. Select population characteristics of Ozark Bass in two northern Arkansas streams were determined, population characteristics of Ozark Bass were compared to Shadow Bass (Ambloplites ariommus) and Rock Bass (Ambloplites rupestris) data collected from previous studies in southern Missouri, and relative condition, length-at-age, and annual survival of Ozark Bass were compared between sample streams. Sampling occurred in Crooked Creek and the Buffalo River during summer 2013 via boat electroshocking. Length and weight data were recorded for all Ozark Bass collected, and fish ages were determined through selective otolith retrieval and age-length keys. Ozark Bass in Crooked Creek had greater relative condition than Ozark Bass in Buffalo River (P P > 0.05) between sexes for fish collected from only the Buffalo River. Ozark Bass mean annual survival was similar between Crooked Creek (55% ± 5% as 95% confidence interval (CI)) and the Buffalo River (50% ± 7% CI) for fish age 2 to 9. Calculated Ozark Bass lengths-at-age for fish from both streams were comparable to the Von Bertalanffy growth estimates, except the Buffalo River age 7 category where there was only one observation. The relationship between Ozark Bass age and length differed between sampled streams, and variability in growth rates and length-at-age were observed among Ambloplites species. Results of this study contribute to the understanding of the population dynamics of the Ozark Bass that will lead to improved fisheries management.

Near-Surface Soil Nutrient Changes over Time under Native Prairie and Managed Agriculture in Arkansas

Landuse change from native prairie to managed agriculture can have substantial impacts on soil nutrient properties. Nutrient release from soil organic matter decomposition is the soil’s inherent source of long-term fertility; thus it is imperative to understand the effects of continued landuse over time to avoid mistaking actual soil property changes with simple inter-annual variability from one year to the next. The objective of this study was to evaluate the effects of landuse (i.e. managed agriculture and native prairie) in two contrasting physiographic regions (i.e. the Ozark Highlands region of northwest Arkansas and the Grand Prairie region of east-central Arkansas) on the change in extractable soil nutrients over a 15-yr period from 2001 to 2016. Extractable soil Ca, Mg, and Zn increased at least two times more over time (P < 0.05) under cultivated agriculture in the Grand Prairie than under native prairie in the Grand Prairie or either landuse in the Ozark Highlands. Averaged across landuse, extractable soil S increased nine times more over time (P < 0.05) in the Ozark Highlands than in the Grand Prairie, while extractable soil Na and Mn increased at least six times more over time (P < 0.05) in the Grand Prairie than in the Ozark Highlands. Averaged across region, extractable soil Mn increased 2.5 times more over time (P < 0.05) under native prairie than under agricultural landuse. Results from this long-term field study clearly demonstrate how landuse and regional soil characteristics can affect near-surface soil nutrient contents, which should be taken into consideration when implementing conservation and/or ecosystem restoration activities.

Increased Effluent Dosage Effects on On-Site Wastewater Treatment Systems of Differing Architecture Type

Approximately 20% of homes nationwide use an on-site treatment system as a form of household wastewater management. However, approximately 10% to 20% of on-site treatment systems malfunction each year, many of which have either failed or exceeded the soil’s long-term acceptance rate (LTAR), causing environmental and human health risks. The objective of this field study was to evaluate the effects of soil condition (e.g., wet and dry) and product architecture type [i.e., chamber, gravel-less-pipe (GLP), polystyrene-aggregate, and pipe-and-aggregate] on in-product solution storage and biomat thickness in a profile-limited soil in northwest Arkansas under increased loading rates and to estimate the LTAR for each product. During Phase I of this study (March 13 to October 4, 2013), effluent loading rates were approximately doubled, while rates were approximately quadrupled during Phase II (October 8, 2013 to May 29, 2014), from the maximum allowable loading rate for each product. The pipe-and-tire-chip, 46-cm-wide trench pipe-and-gravel, and the 25-cm diameter GLP products had the greatest (p < 0.001), while the 31-cm-width and the 5.4-m-long chambers had the lowest (p < 0.001) in-product solution storage during wet-soil conditions of Phase I monitoring. The 25-cm diameter GLP product had the greatest (p < 0.001), while the 61-cm-width, 5.4-m-long chamber had the lowest (p < 0.001) in-product solution storage during Phase II. Results of this study indicate that some alternative products may be able to effectively handle effluent loading rates in excess of those currently allowed by the State of Arkansas. Further research will be required to confirm these interpretations.

美公司开发低成本氟化试剂

美国宾夕法尼亚州费城Ozark氟专用公司计划使用爱达荷大学开发的技术,以比正常价格低一半以上的价格提供两种氛化合物。利用来电子三氟甲基化试剂将CF_3官能基团引入化学产品,例如生产更亲液的医药品农药,或改进聚合物的热稳定性。

Optical water quality and human perceptions of rivers:an ethnohydrology study

Rivers are revered worldwide for their ecologic,scenic,and recreational value.The capacity to communicate effectively among human groups with vested interest in rivers hinges on understanding the nature of human perceptions of water quality and the extent to which they vary intraculturally.Recognizing the intersection between measured water quality and the characteristics of rivers that influence human perceptions facilitates potential for better communication across disciplines and among stakeholders.We conducted interviews and a pile-sort task with water quality experts and nonexperts.Our analysis suggested human evaluation of water quality is guided by culturally constructed criteria,regardless of respondent expertise,experience,or demographics.Cluster analysis results implied that measured physical and chemical parameters of rivers were directly related to the visible attributes used in human judgments.We suggest that,regardless of variability among individual stakeholders,observable characteristics may be the foundation for a common understanding of water quality in rivers.