Methods were developed for the successful artificial fertilization and rearing of the eggs and larvae of the Pacific herring, Clupea pallasii Cuvier. Effects of various constant and changing conditions of salinity (0 ‰ to 34.28 ‰) on the development, mortality and hatching of eggs and on the mortality of larvae were studied. Evidence of an optimum salinity, 11.55 ‰ to 16.24 ‰, for development and survival of eggs is presented, although a wide salinity tolerance, 6.06 ‰ to 34.28 ‰ for both eggs and larvae is evident. Eggs transferred to pond water (0 ‰ salinity) during the first few days of development, perish within a few hours, but if transferred at a later stage, they will survive for at least two days. No apparent correlation exists between survival of eggs and magnitude of salinity change. The presence of two critical stages during embryonic development, the first at blastopore closure, the second prior to and during hatching, have been shown. An optimum survival of eggs was obtained on egg slide sections containing from 75 to 125 eggs. / Science, Faculty of / Zoology, Department of / Graduate

This thesis deals with the importance of salinity to the distribution of three chironomid species of the genus Chironomus (C. anthracinus. C. athalassicus. and C. tentans). Research to date suggests that salinity and coexistence problems are the major factors influencing the distribution of the chironomid fauna of fresh and saline lakes in the Cariboo and Chilcotin areas of central British Columbia. The difference in the distribution of these three Chironomus species is particularly interesting. The investigation of the importance of salinity to their distribution consisted of a study of (i) the salinity tolerance of each species, (ii)the regulation of the haemolymph, and (iii) the influx and efflux of sodium and chloride ions. Several conclusions were drawn from the investigation. A difference in the salinity tolerance of each species was found in the laboratory: C. anthracinus and C. tentans did not survive at lake water conductivities above 9000 micro-o mhos/cm at 25 C, C. athalassicus survived in lake water conductivities at least as high as 15»000 micromhos/cm at o 25 C. Temperature affected the survival of each species in a similar way; at high temperatures survival time decreased. Sodium, potassium, and chloride as well as the concentration of the haemolymph were regulated by the three species at low salinities. C. athalassicus was the only species able to conform at higher external concentrations. C. athalassicus had a low sodium affinity and a powerful sodium uptake system compared to the other species. Chloride affinity and the power of the uptake system exceeded that of C. anthracinus and C. tentans. The general conclusion reached was that salinity does affect the distribution of the three Chlronomus species. More research is called for in this and related areas in order to more fully understand the distribution of the chironomid fauna. / Science, Faculty of / Zoology, Department of / Graduate

Salinity has been shown to reduce vegetative growth, crop quality, and yield in agricultural crops. Remote sensing is capable of providing data about large areas. This project was designed to induce salinity stress in a crop, pak choi, and thereafter monitor the response of the crop as expressed by its spectral reflectances. The project was conducted in the National Taiwan University Phytotron, and spectral data was collected using a GER 2600. Yield and soil salinity (ECe) were also measured. After three seasons of data were collected, wavelengths sensitive to salinity were selected. These wavelengths, which are within the spectral response of biochemicals produced by plants as a response to soil salinity, were used to create two indices, the Salinity Stress Index (SSI) and the Normalized Salinity Stress Index (NSSI). After creating the indices tests were conducted to determine the efficacy of these indices in detecting salinity and drought stresses as compared to existing indices (SRVI and NDVI). This project induced salinity and drought stress in a crop, pak choi, and thereafter monitored the response of the crop as expressed by its spectral reflectances. The SSI and NSSI correlated well to both ECe and marketable yield. Additionally the SSI and NSSI were found to provide statistical differences between salinity stressed treatments and the control treatment. Drought stress was not detected well by any of the indices reviewed although the SSI and NSSI indices tended to increase with drought stress and decrease with salinity stress. As a final test, specific ion toxicities of sodium and chloride were tested against the developed indices (SSI and NSSI) and existing indices (NDVI, SRVI, and NDWI). There were no differences in SSI and NSSI responses to specific ion concentration in the high salinity treatments. These results indicated that the SSI and NSSI are not sensitive to the specific ion concentration in irrigation water. However, the SSI and NSSI were higher for the sodium water than the choride water in the low salinity treatments. It is likely that this difference was caused by the fact that the high SAR water decreased infiltration and caused water stress.

Supplies of nonrenewable fossil fuels are becoming more limited even as they continue to contribute to pollution and economic concerns. Alternative sources of energy must be developed that help minimize these problems. One potential source of energy is the production of biofuels from algae. Here we evaluate algae found in South Texas brackish water ponds used for aquaculture of fish as a possible source of biofuels. In particular, we examine the effects of salinity and pH on the growth and lipid content of the algae. Samples of algae from the ponds exhibited high levels of growth and lipid production at a salinity of 9 ppt and pH 7. These conditions are similar to the natural conditions of the ponds, indicating that they may be a good source of algal biofuels. / text

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8 pp. / The bulletin reviews the factors contributing to the development of salinity and sodium problems in desert turfgrass systems. Key factors include water restrictions, poor water quality, irrigation management, drought and poor soil structure.

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This study explores the dynamics of salt finger convection which occurs when warm, salty water overlies cool and fresh. Salt finger convection is generally observed in mid-latitude regions, particularly in the Atlantic Ocean and Mediterranean Sea, between the base of the mixed layer and the top of the intermediate water. Active salt fingering is characterized by the appearance of well mixed layers separated by thin high-gradient interfaces, known as thermohaline staircases. The data from the CSALT, SFTRE and moored profiler experiments are analyzed to determine the origin of the thermohaline staircases and the mechanism for selection of the preferred layer thickness. Comparisons between these observations and models suggested by Radko are made. We use a combination of data analysis and analytical considerations to estimate the vertical heat/salt mixing rates and their dependencies on the large-scale environmental parameters. The three dimensional structure of these staircases and their evolution in time is explained by considering the secondary instabilities of a series of diffusive interfaces and the temporal and spatial structure of the high resolution data. Using a Parabolic Equation model we have investigated the influence of thermohaline staircases on acoustic propagation Also we experiment the sensitivity of the acoustic variations to changes in frequency and source depth. / Royal Australian Navy author