Carcass orientation and drip time affect potential surface water carryover for broiler carcasses subjected to a post-chill water dip or spray

Didymosphenia geminata (Lyngbye) Schmidt (commonly called didymo) is an invasive diatom and of concern to fisheries managers in North America and more recently New Zealand. Didymo grows in thick mats in several river systems on the South Island of New Zealand, often smothering entire river beds. Salmonid eggs, deposited in gravel nests (redds), depend on constant water exchange across the riverbed to provide oxygen-rich water for development. Thick didymo mats might restrict the flow of oxygen-rich water into spawning gravels, resulting in increased egg mortality and reduced trout recruitment. The present study measured hyporheic hydraulic conditions in trout redds with varying didymo cover in the Clutha River catchment, South Island, New Zealand. Didymo cover had no significant effects on several hydraulic variables (flow into the substrate, hydraulic conductivity and hyporheic oxygen concentration). However, there was a significant difference in the potential surface water–groundwater exchange between sites, suggesting some effect of didymo on hydraulic conditions. Considering the limited number of replicates, the impact of didymo on trout redds in the Clutha River cannot be excluded. The present study highlights the need for further research on the possible effects of didymo on important surface water–groundwater exchange processes.

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Aqueous geochemistry of the Englishman River Watershed, Parksville, British Columbia for use in assessment of potential surface water-groundwater interaction

10.4095/292678 ◽

2013 ◽

Author(s):

S K Provencher ◽

B Mayer ◽

S E Grasby

Keyword(s):

British Columbia ◽

Surface Water ◽

Potential Surface ◽

Aqueous Geochemistry ◽

River Watershed

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PEMETAAN POTENSI KERENTANAN PENCEMARAN AIR PERMUKAAN UNTUK PENGENDALIAN SANITASI LINGKUNGAN DI KABUPATEN BULELENG (Mapping on the potential vulnerability of surface water pollution for environmental sanitation control in Buleleng Regency)

Jurnal Penelitian Pengelolaan Daerah Aliran Sungai ◽

10.20886/jppdas.2021.5.1.1-20 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1-20

Author(s):

Arief Wicaksono ◽

◽

Galih Dwi Jayanto ◽

Keyword(s):

Water Pollution ◽

Surface Water ◽

Land Cover ◽

Potential Surface ◽

Control Surface ◽

Septic Tank ◽

Water Quality Control ◽

Annual Average ◽

Surface Water Pollution ◽

Average Rainfall

One of the efforts to prevent water pollution is done by mapping of potential pollution vulnerability to support water quality control policy making. The research location is in Panas Sub-watershed, a part of the Saba Watershed which originates on the northwest slope of the Bratan Volcano Complex and upstream is Lake Tamblingan, Buleleng Regency. The objectives of the study include: 1) mapping the parameters of potential surface water pollution vulnerability, 2) mapping land cover changes in 2000 and 2016, 3) mapping the potential surface water pollution vulnerability and its dynamics in 2000 and 2016, and 4) formulating a management recommendation to control surface water pollution. Mapping the potential surface water pollution vulnerability was conducted by GIS and Point Count System Model (PCSM) method using parameters of slope, land cover, and annual average rainfall. The results showed that some of the upstream and middle areas of the Panas Sub-watershed were categorized as high potential vulnerability caused by steep slopes, plantation cover, and annual average rainfall of 2,251 - 2,500 mm/year. Various recommendations to control surface water pollution are conducting integrated waste management individually or in groups, such as collectively septic tank construction, waste disposal organization, and waste water management installation; providing directions for appropriate land cultivation for farmers so that the pollutant load due to the use of pesticides could be controlled; as well as controlling and supervising the tourist area around Tamblingan Lake.

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Application of a Simple Cold Stub to the Direct Observation of Frozen Hydrated Sand

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071508 ◽

1973 ◽

Vol 31 ◽

pp. 212-213

Author(s):

John M. Wehrung ◽

Richard J. Harniman

Keyword(s):

United States ◽

Surface Water ◽

Direct Observation ◽

Controlled Study ◽

Clay Particles ◽

Organic Debris ◽

Rock Formations ◽

Water Tables ◽

Permeable Rock ◽

Natural Means

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.

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