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Application to land is the preferred method for the treatment of wastewaters in New Zealand. For land treatment to be effective, it is essential that the soils can accept the volumes of wastewater applied and degrade or store the constituents in the wastewater. We report on 14 soil chemical, biochemical and physical characteristics of soils (0-10 cm depth) used for wastewater treatment at the Fontcrra dairy factories at Hautapu, Lichfield and Edgecumbe in the North Island of New Zealand. The soils are under grazed pasture for dairying and receive wastewater by spray irrigation. The soils were monitored approximately every 2 years between 1995 and 2005 and at the end of monitoring had been under irrigation for 10-26 years. Matched, non-irrigated pasture soils on adjacent dairy farms were sampled for comparison. The wastewater composition from the three factories differed, reflecting the products manufactured. Loadings were greatest at the Flautapu factory, which also had the longest history of irrigation (26 years). At all three sites, the physical characteristics of irrigated soils were very similar to their non-irrigated comparisons. A consistent trend was for microbial mass and activity, and particularly nitrogen (N) turnover, to be markedly greater on the irrigated soils. The C (carbon): N ratios of irrigated and non-irrigated soils at Lichfield and Edgecumbe were similar, but at Hautapu the C:N ratio of irrigated soil was 8.3 and significantly (P Additional keywords: biochemical indices, dairy factory, effluent, land treatment, soil monitoring, soil storage of N, water quality. Received 11 December 2014, accepted 3 February 2015, published online 30 June 2015, Introduction The disposal of wastewater by irrigation onto land has become the preferred method for the treatment of liquid wastes in New Zealand (Selvarajah 1996; Cameron et al. 1997; Liu [...]

For migrating tides or fast-moving planetary waves, polarization relations derived from the linear wave equations are required to accurately derive the wind components from the temperature field. A common problem in diagnosing winds from the measured temperature is the error amplification associated with apparent singularities in the wave polarization relations. The authors have developed a spectral module that accurately derives tidal winds from the measured tidal temperature field and effectively eliminates the error amplification near the apparent singularities. The algorithm is used to perform a diagnostic analysis of tidal winds and the Eliassen--Palm (EP) flux divergence in the mesosphere and lower thermosphere (MLT) based on the zonal mean and tidal temperature fields derived from 6 yr of temperature measurements made by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the Thermosphere--Ionosphere--Mesosphere Energetics and Dynamics (TIMED) satellite. The derived zonal mean wind and diurnal tidal amplitude reveal new insights into the mesospheric biennial oscillation (MBO) that exists in the MLT at both equatorial and midlatitude regions. The equatorial MBO in the zonal mean wind is present in the entire mesosphere from 50 to 90 km. The equatorial MBO in the temperature amplitude of the diurnal tide occurs near the mesopause region between 80 and 90 km and is largely coincident with the downward phase propagation of the equatorial MBO in the zonal mean wind, indicating a possible mechanism of wave--mean flow interaction between the two. On the other hand, the newly discovered midlatitude MBOs in zonal mean wind and the meridional wind in diurnal tide occur at different altitudes, suggesting possibly a remote forcing--response relationship. The acceleration or deceleration of the zonal mean wind due to EP flux divergence that is contributed by the migrating tides peaks at mid-latitudes with a typical value of 10-20 m [s.sup.-1] [day.sup.-1] around 95 km.

High-resolution analyses of the Mg concentration in authigenic calcite in five cores from Lake Edward provide a water balance history of central equatorial Africa spanning the past 1400 yr. A high ratio of Mg to Ca (%Mg) indicates strong droughts in central Africa during the Little Ice Age (A.D. 1400-1750), in contrast to records from Lake Naivasha, Kenya, which suggest a wet Little Ice Age. This spatial pattern in Africa likely arose due to coupled changes in the high latitudes, the position of the Intertropical Convergence Zone, and the El Nino-Southern Oscillation (ENSO) system. Our results further suggest that the patterns and variability of twentieth-century rainfall in central Africa have been unusually conducive to human welfare in the context of the past 1400 yr. Keywords: Lake Edward, Africa, paleoclimate, carbonate, Little Ice Age, Medieval Warm Period.