No abstract

The uptake of magnesium by plants from the use of the magnesium silicates serpentine and dunite was compared with that from dolomite and talc-magnesite, the latter two minerals being commonly used magnesium fertilisers in Nelson.Tobacco plants, white clover, and perennial ryegrass were grown in pots filled with sawdust. Plant nutrients were supplied in solution, except magnesium, which was applied at different rates of ground fertiliser. Field trials with tobacco and pasture are also described.When the four magnesium fertilisers were compared on an equal weight basis, dunite proved to be the most efficient; serpentine was equal to dolomite in certain cases but superior in the pot trials with tobacco and clover. Talc-magnesite gave variable results.Solubility Itests with water and dilute acids showed that the magnesium silicates serpentine and dunite are readily broken down, releasing magnesium.

Adult salmon that stray when they escape into nonnatal streams to spawn is a natural phenomenon that promotes population growth and genetic diversity, but excessive stray rates impede adult abundance restoration efforts. Adult San Joaquin River (SJR) Basin fall-run Chinook salmon (Oncorhynchus tshawytscha) that return to freshwater to spawn migrate through the San Francisco Bay and Sacramento-San Joaquin River Delta (Delta). The Delta has been heavily affected by land development and water diversion. During the fall time-period for the years 1979 to 2007 Delta pumping facilities diverted on average 340% of the total inflow volume that entered the Delta from the SJR. The hypothesis tested in this paper is that river flow and Delta exports are not significantly correlated with SJR salmon stray rates. Adult codedwire-tagged salmon recoveries from Central Valley rivers were used to estimate the percentage of SJR Basin salmon that strayed to the Sacramento River Basin. SJR salmon stray rates were negatively correlated (P = 0.05) with the average magnitude of pulse flows (e.g., 10 d) in mid-to late-October and positively correlated (P = 0.10) with mean Delta export rates. It was not possible to differentiate between the effects of pulse flows in October and mean flows in October and November on stray rates because of the co-linearity between these two variables. Whether SJR-reduced pulse flow or elevated exports causes increased stray rates is unclear. Statistically speaking the results indicate that flow is the primary factor. However empirical data indicates that little if any pulse flow leaves the Delta when south Delta exports are elevated, so exports in combination with pulse flows may explain the elevated stray rates. For management purposes, we developed two statistical models that predict SJR salmon stray rate: (1) flow and export as co-independent variables; and (2) south Delta Export (E) and SJR inflow (I) in the form of an E:I ratio.

Calcium nitrate and calcium chloride tree sprays at different concentrations are compared. Calcium chloride, with about twice the calcium content of the nitrate, gave as good-control of bitter pit at half the concentration of the nitrate, which relates the effectiveness of these materials to their calcium content. Colour development on apples was better with calcium chloride than with the nitrate. The slow movement of calcium through apple flesh is demonstrated. When inadequate calcium sprays are used, -bitter pit may develop internally without showing its-presence on the apple surface.

Because of mounting inflows of sewage and organic industrial effluents in Nelson Haven, Waimea Inlet, and Tasman Bay, a water quality survey to obtain background information, on 17 parameters from 28 sites was made during 1975.Some water samples collected near effluent discharges showed high levels of nitrate, total nitrogen, total phosphorus, volatile solids, ATP, heterotrophic potential, total bacteria, viable bacteria, and coliform bacteria. Measurements were also made of temperature, salinity, dissolved oxygen, pH, suspended solids, and chlorophyll a; counts were made for confirmed faecal coliforms and confirmed Escherichia coli (Type I).Water from sites remote from effluent discharges showed characteristics of normal seawater: water turbulence and tidal flushing appeared to be rapidly degrading, diluting, and dispersing the organic contaminants.