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Translocated (oxalate-soluble) A1 and Fe are present predominantly in inorganic forms in the B, horizons of the five pcdzol profiles examined: A1 as imogolite and proto-imogolite allophanes, and Fe as a separate oxide phase. Below the top few cm of the B, horizon, over 75 per cent of the extractable (acid-plus alkali-soluble) organic matter is present as Al-fulvates, largely sorbed on allophanic material. The Bh horizons of the Iron Humus Podzol and Iron Podzol intergrades are distinguished by very high levels of organically bound Fe (soluble in EDTA solution), five to ten times more than in immediately adjacent A, or B, horizons, and also by larger humic acid contents than in comparable B, levels in typical Iron Podzols. Inorganic forms of translocated A1 and Fe are probably absent from two of the three Bh horizons examined, and also from the Bhg horizon overlying the thin iron pan in the Peaty Podzol. The organic matter in this Bhg horizon is saturated with Al rather than Fe. Chemical and physical processes which could lead to evolution of a profile along the genetic sequence, Iron Podzol, Iron Humus Podzol, Peaty Podzol, are postulated.

The loss of P in subsurface drainage from lysimeters (0.5 ha), managed as either monoculture grass or grass‐clover for the last 9 yr have been quantified. Both systems received two to three cattle slurry applications annually and were cut two to three times before being grazed by dairy cattle. Mineral fertilizer‐P was applied only to the grass‐clover (about 25 kg P ha−1 yr−1). After 9 yr, NaHCO3‐soluble P in the topsoil (0–10 cm) averaged 38 and 47 mg P kg−1 for the grass and grass‐clover respectively, giving an average increase of 1.0 mg OIsen‐P kg−1 yr−1 in the grass‐clover. Drainage‐weighted molybdate‐reactive phosphorus (MRP) and total phosphorus (TP) concentrations ranged from 0.16 to 0.38 mg P L−1 and 0.45 to 0.79 mg P L−1, respectively during the 2‐yr study period. The MRP and TP losses in subsurface‐flow from the grass‐clover (1.68–2.03 and 3.47–5.03 kg P ha−1 yr−1, respectively) were significantly larger than those from the grass (1.27–1.34 and 2.97–3.58 kg P ha−1 yr−1, respectively). Averaged across years and pastures, MRP accounted for 42% of the TP loss, while a non‐MRP form accounted for 41% of the TP loss through field drains. Particulate‐associated P represented about 17% of the TP loss. The P losses in subsurface runoff measured in the present study were much larger than previous estimates. The results also showed that, despite the subsoil having much larger P‐sorption capacity than the topsoil, significant amounts of P losses could occur through preferential hydrological pathways.

New Zealand tertiary education is currently undergoing extensive reviews and reorganisation in its quest for achieving a 'knowledge society'. Central to many of these new developments is the need to extend the participation rates of groups previously under-represented. Increasingly, the debate is also centred on how to retain these under-represented groups once they are recruited into tertiary programmes. This article reports a large-scale study of the factors that influence successful completion of tertiary qualifications for Pasifika students. Using a diverse range of data sources throughout New Zealand, the study identified motivation and attitudes, pressures from family groups, peer groups and finances, lack of support services and language issues as negative factors, while the availability of Pasifika staff, promoting a Pasifika 'presence' in institutions, positive role models, appropriate pedagogy and readilyavailable information were all positive factors in increasing retention.

Assessment in higher education serves multiple purposes such as providing information about student learning, student progress, teaching quality, and program and institutional accountability. Yet, little is known about faculty and students' attitudes regarding different aspects of assessment that have wide-ranging implications for policy and practice in tertiary institutions. To investigate these views, parallel surveys of conceptions of assessment were administered to faculty and undergraduate students across four tertiary institutions including universities, an indigenous tertiary institution, and an institute of technology. A mean and covariance structures approach was used to test for measurement invariance and latent means differences between faculty and students regarding their conceptions of assessment. Results revealed differences in the latent means across the two groups. Faculty were likely to view assessment as a trustworthy process aiding teaching and learning, whereas students viewed assessment as focussed primarily on accountability and perceived assessment as irrelevant or even ignored in the teaching and learning process. These findings highlight the importance of ensuring that assessment policy and practices are fit for purposes, and are being carried out with integrity in ways that are transparent to and understood by both staff and students. While these results show how staff and students view assessment practices, one should keep in mind that while the

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Abstract:To remotely monitor vegetation at temporal and spatial resolutions unobtainable with satellite-based systems, near remote sensing systems must be employed. To this extent we used Normalized Difference Vegetation Index NDVI sensors and normal digital cameras to monitor the greenness of six different but common and widespread High Arctic plant species/groups (graminoid/Salix polaris; Cassiope tetragona; Luzula spp.; Dryas octopetala/S. polaris; C. tetragona/D. octopetala; graminoid/bryophyte) during an entire growing season in central Svalbard. Of the three greenness indices (2G_RBi, Channel G% and GRVI) derived from digital camera images, GRVI showed the most significant correlations with NDVI among all vegetation types. The GRVI (Green-Red Vegetation Index) is calculated as (G DN − R DN )/(G DN + R DN ) where G DN is Green digital number and R DN is Red digital number. Both NDVI and GRVI successfully recorded timings of the green-up and plant growth periods and senescence in all six plant species/groups. Some differences in phenology between plant species/groups occurred: the mid-season growing period reached a sharp peak in NDVI and GRVI values where graminoids were present, but a prolonged period of higher values occurred with the other plant species/groups. In particular, plots containing C. tetragona experienced increased NDVI and GRVI values towards the end of the season. NDVI measured with active and passive sensors were strongly correlated (r > 0.70) for the same plant species/groups. Although NDVI recorded by the active sensor was consistently lower than that of the passive sensor for the same plant species/groups, differences were small and likely due to the differing light sources used. Thus, it is evident that GRVI and NDVI measured with active and passive sensors captured similar vegetation attributes of High Arctic plants. Hence, inexpensive digital cameras can be used with passive and active NDVI devices to establish a near remote sensing network for monitoring changing vegetation dynamics in the High Arctic.