Streambank Erosion

Streambank erosion refers to the removal of soil and other material, such as rock and vegetation, from the streambank (Figure 1). Streambank erosion is a naturally occurring process, but the rate at which it occurs is often increased by anthropogenic or human activities such as urbanization and agriculture. Changes in land use can cause streambanks to erode at rates much faster than those seen in natural, undisturbed systems

Hydrologic Models

Water is a vital part of our everyday lives. Water is necessary for domestic activities such as drinking, cooking and cleaning; agricultural practices such as growing crops and livestock; and industrial uses such as manufacturing and transporting products (Figure 1). Some of our water use is seen, such as when we take a shower. However, most of our water use is hidden, meaning that water was used to make a product although little to no water may be in the product itself. Because water is so important, a branch of science is devoted to its study

Designing Contour Weep Berms to Reduce Agricultural Nonpoint Source Pollution

Nonpoint source pollution (NPS) of surface waters is a significant issue in agricultural lands, and best management practices (BMPs) are often used to reduce these impacts. Since the effectiveness of a BMP depends on a large number of widely varying factors, it is important to continue to develop BMPs in order to provide designers with more tools to use to maximize NPS removal. The contour weep berm is a new structural BMP constructed out of earth and subsequently vegetated. It is a linear BMP that is used in combination with a down-gradient vegetated filter strip or forested riparian buffer. Preliminary field evaluations of the contour weep berm indicate it is effective at reducing runoff volumes and peaks, promoting infiltration, and reducing sediment concentrations in runoff. Procedures for designing a contour weep berm are presented along with a design example. Linear BMPs, such as the contour weep berm, can provide producers with another means of effectively controlling NPS

WETLANDS AND COASTAL SYSTEMS: PROTECTING AND RESTORING VALUABLE ECOSYSTEMS

Wetlands and coastal systems are unique, highly productive, and often threatened landscapes that provide a host of services to both humans and the environment. This article introduces a five-article Wetlands and Coastal Systems Special Collection that evolved from a featured session at the 2015 ASABE Annual International Meeting in New Orleans, Louisiana. The Collection provides perspectives on tools and techniques for enhancing the protection and restoration of wetlands and coastal systems with emphasis on vegetation, hydrology, water quality, and planning. Topics span the Florida Everglades (two articles) and Virginia floodplain (one article) wetland systems and include remote sensing (one article) and geographic information system-based (one article) modeling tools developed to address wetland planning and analysis issues. The Special Collection provides valuable information to engineers, scientists, planners, and other specialists working on large-scale and small-scale wetlands and coastal systems

Development and Deployment of a Bioreactor for the Removal of Sulfate and Manganese from Circumneutral Coal Mine Drainage

Surface mining, in the form of contour mining and mountain-top removal, is a common means for retrieving coal in the Appalachian Coal Belt region of Kentucky. Overburden or excess spoil generated by these two methods is placed in valley fills. Traditionally Constructed fills have been shown to adversely impact headwater ecosystems via stream burial and through alterations to the hydrology, sediment supply, water quality and biological composition of downstream reaches. Mine drainages emanating from the toe of valley fills often contain elevated levels of total dissolved solids and heavy metals. Drainage chemistry from Guy Cove, a valley fill located in eastern Kentucky, exhibited a mean pH of 6.5 and Fe, Mn and SO4 concentrations of 1.5, 14, and 1264 mg L-1, respectively. The objective of this research was to develop an anaerobic bioreactor for the purpose of reducing Mn and SO4 concentrations in the mine drainage. Development began with batch experiments that tested five different organic carbon sources and five different inorganic substrates. A synthetic mine drainage with a pH of 6.2 and Mn and SO4 concentrations of 90 and 1,500 mg/L, respectively, was used in the experiment. Manganese and SO4 removal varied widely between treatment matrices, with removal rates \u3c 10 to 100% for Mn and \u3c 10 to \u3e 80% for SO4. The substrate sources which provided the most treatment were hardwood mulch and biosolids combined with creek sediment. Subsequent experiments were performed using the synthetic mine drainage in small bioreactors (55 liter plastic tanks) filled with creek sediment with either hardwood mulch or biosolids, each replicated three times. Over a 65 day treatment period \u3e 90% of the Mn and 70% of the SO4 was removed. There were no statistical differences between the two organic substrates. Using this information, in-situ bioreactors consisting of two 5,500 liter plastic septic tanks filled with creek sediment, hardwood mulch and manure compost were installed at Guy Cove. Mine drainage was collected in a sump and conveyed through the inline bioreactors by gravity. Gate valves were used to control flow through the bioreactors. After a 10-month monitoring period, the in-situ bioreactors removed 12, 11, and 64% of Mn, SO4 and Fe from the drainage, respectively. Results from the field differed greatly from those observed under controlled laboratory conditions. Efforts to improve the efficiency of the in-situ bioreactors are underway

A Review of Time Courses and Predictors of Lipid Changes with Fenofibric Acid-Statin Combination

Fibrates activate peroxisome proliferator activated receptor α and exert beneficial effects on triglycerides, high-density lipoprotein cholesterol, and low density lipoprotein subspecies. Fenofibric acid (FA) has been studied in a large number of patients with mixed dyslipidemia, combined with a low- or moderate-dose statin. The combination of FA with simvastatin, atorvastatin and rosuvastatin resulted in greater improvement of the overall lipid profile compared with the corresponding statin dose. The long-term efficacy of FA combined with low- or moderate- dose statin has been demonstrated in a wide range of patients, including patients with type 2 diabetes mellitus, metabolic syndrome, or elderly subjects. The FA and statin combination seems to be a reasonable option to further reduce cardiovascular risk in high-risk populations, although trials examining cardiovascular disease events are missing

Livestock Grazing Management Impacts on Stream Water Quality: A Review

Controlling agricultural nonpoint source pollution from livestock grazing is a necessary step to improving the water quality of the nation’s streams. The goal of enhanced stream water quality will most likely result from the implementation of an integrated system of best management practices (BMPs) linked with stream hydraulic and geomorphic characteristics. However, a grazing BMP system is often developed with the concept that BMPs will function independently from interactions among controls, climatic regions, and the multifaceted functions exhibited by streams. This paper examines the peer reviewed literature pertaining to grazing BMPs commonly implemented in the southern humid region of the United States to ascertain effects of BMPs on stream water quality. Results indicate that the most extensive BMP research efforts occurred in the western and midwestern U.S. While numerous studies documented the negative impacts of grazing on stream health, few actually examined the success of BMPs for mitigating these effects. Even fewer studies provided the necessary information to enable the reader to determine the efficacy of a comprehensive systems approach integrating multiple BMPs with pre-BMP and post- BMP geomorphic conditions. Perhaps grazing BMP research should begin incorporating geomorphic information about the streams with the goal of achieving sustainable stream water quality

The Effect of Statins on Ocular Disorders: A Systematic Review of Randomized Controlled Trials

Aim: Statins have been established in the market not only due to their ability to lower plasma cholesterol levels but also due to their pleiotropic effects. In the literature, there is a controversy regarding the role of statins in ophthalmology. We aimed to systematically address the possible effect of statin therapy on ocular diseases and to identify if there is a beneficial relationship. Methods: We searched PubMed and Cochrane Library databases up to 31 December 2022 for studies evaluating the effect of statins on ocular diseases. We included all relevant Randomized Control Trials (RCTs) that have been conducted in the adult population. PROSPERO registration number: CRD42022364328. Results: Nineteen RCTs were finally considered eligible for this systematic review, with a total of 28,940 participants. Ten studies investigated the role of simvastatin, suggesting a lack of cataractogenic effect and a possible protective role in cataract formation, retinal vascular diseases, and especially diabetic retinopathy, age-related macular disease progression, and non-infectious uveitis. Four studies investigated lovastatin, showing no cataractogenic effect. Three studies examined atorvastatin, revealing conflicting results regarding diabetic retinopathy. Two studies examined rosuvastatin, indicating a possibly harmful effect on lenses and a significant protective effect on retinal microvasculature. Conclusions: Based on our findings, we believe that statins have no cataractogenic effect. There are indications that statins may have a protective role against cataract formation, AMD, diabetic retinopathy progression, and non-infectious uveitis. However, our results were insufficient for any robust conclusion. Future RCTs, with large sample sizes, on the current topic are therefore recommended to provide more solid evidence. © 2023 by the authors