scholarly journals A Water Temperature Simulation Model for Rice Paddies With Variable Water Depths

2017 ◽  
Vol 53 (12) ◽  
pp. 10065-10084 ◽  
Author(s):  
Atsushi Maruyama ◽  
Manabu Nemoto ◽  
Takahiro Hamasaki ◽  
Sachinobu Ishida ◽  
Tsuneo Kuwagata
2013 ◽  
Vol 405-408 ◽  
pp. 358-362 ◽  
Author(s):  
Wei Sheng Xu

approximate analysis formula for the water flow of single fracture and variable water temperature has been deduced considering the impact of water temperature to rock fracture seepage. Following conclusions were drawn: (1) The water head and the hydraulic gradient in single-fissure have nonlinear relation. Seepage curve was convex curve if water flows from higher temperature areas to lower temperature area. On this condition, the water head slants low under liner seepage simplification. On the contrary, Seepage curve is convex curve if water flows from lower temperature areas to higher temperature areas, and the water head slants high. (2) In a single fracture, the hydraulic gradient is smaller in the higher temperature zone and is larger in the lower temperature zone. The higher the mean water temperature of fracture was, and the faster the flow velocity was.


2011 ◽  
Vol 1 (32) ◽  
pp. 29 ◽  
Author(s):  
Jane McKee Smith ◽  
Robert E. Jensen ◽  
Andrew B. Kennedy ◽  
J. Casey Dietrich ◽  
Joannes J. Westerink

Few wave measurements have been made in wetlands during high-energy, surge events, such as hurricanes. During Hurricane Gustav in 2008, many nearshore wave measurements were made in Southeastern Louisiana. These data are used to verify a nearshore wave modeling system and to explore the characteristics of hurricane waves in wetlands. The modeling system consists of the wave generation model WAM, the nearhsore wave model STWAVE, and the circulation model ADCIRC. The measurements confirm reasonable success in modeling the waves. The measurements and modeling also expose some of the problems of measuring waves in highly-variable water depths under hurricane forcing and modeling waves in rapidly degrading wetlands.


Author(s):  
J. A. Pinkster

Prediction of the wave-induced motions of vessels moored in locations with complex bathymetry involving variable water depth represent a challenge for standard 3-dimensional diffraction methods. In this paper a modified diffraction method is introduced based on a multi-domain approach capable of handling different water depths in each domain. The theoretical background is briefly discussed along with some aspects of the numerical implementation. The method is applied to three examples which are known to present difficulties for the standard diffraction codes based on a single water depth and one involving infinitely long reflecting boundaries.


2014 ◽  
Vol 955-959 ◽  
pp. 3190-3197
Author(s):  
Chang Jun Qi ◽  
Yuan Zhai ◽  
Bao Hong Lu ◽  
Qing Gai Wang

The vertical distribution of the reservoir water temperature depends on the scale of the reservoir, regulation manners, as well as the hydrological and geological conditions near reservoir areas. Based on water temperature observation from three different regulation reservoirs, this paper analyses the vertical distribution of these reservoirs water temperature. The preliminary conclusions are: for multi-annual regulation reservoirs, the upper zones usually have stable temperature stratification structures, while the lower zones have constant low temperature; for annual regulation reservoirs, water temperature distribution changes with depth; for the daily regulation reservoirs with low water depths present mixed vertical distributions of water temperature.


2017 ◽  
Vol 601-602 ◽  
pp. 346-355 ◽  
Author(s):  
Nobuko Katayanagi ◽  
Tamon Fumoto ◽  
Michiko Hayano ◽  
Yasuhito Shirato ◽  
Yusuke Takata ◽  
...  

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
David H. Ward ◽  
Courtney L. Amundson ◽  
Patrick J. Fitzmorris ◽  
Damian M. Menning ◽  
Joel A. Markis ◽  
...  

Abstract Rhodoliths are important foundation species of the benthic photic zone but are poorly known and rarely studied in Alaska. A bed of Lithothamnion soriferum rhodoliths was discovered in 2008 in Kinzarof Lagoon, Alaska, a shallow-water embayment dominated by eelgrass (Zostera marina). Rhodolith spatial extent and biomass were estimated to assess trends and environmental factors that may influence rhodolith distribution and abundance during four years spread over a 12-year period (2008–2010, and 2019). Presence and biomass of rhodoliths were negatively associated with percent eelgrass cover. Biomass of rhodoliths also decreased with increased water temperature. Rhodoliths occurred in two primary areas of the lagoon, a 182 ha core area in a shallow water (mean tide depth of −0.03 m MLLW) tidal channel with low eelgrass density, and a 22 ha outlying area at shallower water depths (>0.2 m MLLW) with moderate to high eelgrass cover. There was no apparent trend in rhodolith biomass over the study period despite wide variation in mean annual estimates. This study establishes a baseline for continued investigations and monitoring of this important benthic resource in Alaska.


1993 ◽  
Vol 119 (11) ◽  
pp. 1251-1273 ◽  
Author(s):  
Midhat Hondzo ◽  
Heinz G. Stefan

1977 ◽  
Vol 14 (2) ◽  
pp. 239-249 ◽  
Author(s):  
R. K. Pickerill ◽  
B. V. Roulston ◽  
J. P. A. Noble

A suite of previously undescribed trace fossils from the three main sections of the Silurian (Chaleurs Group) of the southeastern Gaspé Peninsula are examined in detail. The ichnofauna includes a diverse assemblage of forms produced essentially by vermiform and other problematica (Chondrites,Cosmorhaphe; Diplocraterion parallelum Torell, Gyrophyllites, Monocraterion, Planolites annularius Walcott, Planolites cf. beverleyensis (Billings), Rhizocorallium cf. irregulare (Mayer), Scalarituba missouriensis Weller, Skolithos, Zoophycos, pholadid-like bur-rows and grazing trails). The trace fossils occur in four distinctive and recurring associations. Three of these associations, the Scalarituba – Cosmorhaphe, Chondrites, and Diplocraterion associations are useful paleobathymetric and paleoenvironmental indicators, as they all occur in lagoonal, intertidal, or shallow subtidal regimes. The Scalarituba – Cosmorhaphe and Chondrites associations are characterized by shallow burrows and developed in moderately low energy conditions. The monospecific Diplocraterion association developed on an unstable substrate subject to higher rates of sedimentation. The fourth, Zoophycos association, is found in rocks deposited in variable water depths and is a much less useful paleobathymetric and paleoen-vironmental indicator so that conclusions regarding its distribution must be made with extreme caution.


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