New Zealand soils

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Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

the Hagen–Poiseuille and Darcy laws (Sutera and Skalak, 1993) and by incorporating three semi-empirical tortuosity parameters. The model is based on the soil pore-size distri- bution and has been successfully validated using the Euro- pean HYPRES (Wösten et al., 1998, 1999; Lilly et al., 2008) and the UNSODA databases (Leij et al., 1999; Schaap and van Genuchten, 2006) but has not yet been applied to New Zealand soils. Most New Zealand soils are considered to be structured, with two-stage drainage (Carrick et al., 2010; McLeod et al., 2008) and bimodal pore-size distribution (e.g. Durner, 1994). Romano and Nasta (2016) showed by using the HYDRUS-1D package that large errors arise in the com- putation of the water fluxes if unimodal θ (h) and K(θ ) are used in structured soils. We therefore propose to improve the unimodal Pollacco et al. (2013) K s model so that it can pre-

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Which rhizobia nodulate which legumes in New Zealand soils?

Which rhizobia nodulate which legumes in New Zealand soils?

A diverse range of rhizobia genera and species nodulate legumes in New Zealand soils. It seems likely that further rhizobia will be associated with the many naturalised legumes still to be examined. Generally, native, crop and weed legumes are nodulated by different groups of rhizobia with crop legumes primarily effectively nodulated by rhizobia used as inoculum. However, lucerne can be nodulated by Rhizobium strains which give poor growth. It is not known how widespread these strains are and this warrants further study. Also, further work is required to assess the level of persistence of lucerne rhizobial inoculants in different soils in New Zealand. Bradyrhizobia that cross-nodulate lupins, gorse, European broom and tagasaste are of widespread occurrence in New Zealand and these require further characterisation. Also, further work is required to fully assess if Lupinus polyphyllus benefits from rhizobial inoculants in high country soils in the South Island..

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Organic amendments for reducing the plant uptake of cadmium from New Zealand soils

Organic amendments for reducing the plant uptake of cadmium from New Zealand soils

elements  should  form  specific  complexes  with  each  other  in  soil,  rendering  Cd  unavailable  for  plant  uptake   (Pearson,  1968).  Many  studies  have  been  carried  out  looking  at  the  effect  of  S  on  Cd  uptake  by  plants.    Gao   et  al.  (2008)  reported  that  when  Cd  was  present  in  soils  at  high  concentrations  the  addition  of  S  supressed   the  plant  uptake  of  Cd.    Although,  the  supply  of  S  was  seen  to  increase  the  supply  of  Cd  to  rice  when  the   soil  Cd  concentration  was  low.    This  indicated  that  where  higher  concentrations  of  Cd  are  present,  S   additions  are  more  likely  to  reduce  plant  uptake.    Karlsson  et  al.  (2007)  reported  that  complexation  with  S   groups  might  be  the  dominant  binding  mechanism  of  Cd  in  soils  that  have  <5  mg  Cd/g  organic  C.    Martinez   et  al.  (2002)  used  Sulphur  –  X-­‐ray  absorption  near  edge  spectroscopy  (XANES)  analyses  that  showed  a  high   percentage  (35-­‐45%)  of  the  total  S  that  exists  in  soil  is  found  as  sulphides  and  thiols,  which  are  known  to   form  complexes  with  Cd,  therefore  reducing  solubility  in  soil.    Organic  matters  are  known  to  contain  trace   amounts  of  thiols  (Ravichandran,  2004),  therefore  we  would  expect  when  present  in  the  soil  that  Cd  will  be   preferentially  bound  and  form  complexes  with  these  thiols,  reducing  Cd  solubility  and  uptake.    Although,   Cui  et  al.  (2016)  reported  that  the  addition  of  elemental  S  increased  the  shoot  concentrations  of  Cd,   indicating  that  S  resulted  in  Cd  becoming  more  soluble  in  the  soil.    The  reasoning  behind  this  being  that  the   elemental  S  acidified  the  soil  making  Cd  more  mobile.  

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Nitrification activity in New Zealand soils and the variable effectiveness of dicyandiamide : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph D ) in Soil Science at Massey University, Palmerston Nort

Nitrification activity in New Zealand soils and the variable effectiveness of dicyandiamide : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph D ) in Soil Science at Massey University, Palmerston North, New Zealand

The Literature Review showed that N transformations in hill country soils are highly variable across different landscapes. It was concluded that the history of N application, the C/N ratio of the soil and the SOM quality are the factors that are likely to contribute to this variation. However, it is not known whether the populations of autotrophic AOB may contribute to this variability or whether these soils contain some naturally- occurring inhibiting factor that slows down the nitrification rate in some way. A small study was therefore undertaken to investigate this issue a little further (Chapter 5). This incubation study investigated the nitrification activity in two soils collected from the same hill country paddock. One sample was collected from relatively flat camp site areas in the paddock and the second sample was collected from adjacent steeply sloping areas. The final chapter (Chapter 6) followed up the findings in Chapter 5 and used a series of laboratory incubations to investigate whether the low-nitrifying steep slope soil contained some inhibiting agent that could also inhibit nitrification when the soil was mixed with the high-nitrifying camp site soil.

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A fractionation of acid soluble non exchangeable potassium in some New Zealand soils into available and non available forms : a thesis presented for the degree of Doctor of Philosophy, University of New Zealand [Massey Agricultural College]

A fractionation of acid soluble non exchangeable potassium in some New Zealand soils into available and non available forms : a thesis presented for the degree of Doctor of Philosophy, University of New Zealand [Massey Agricultural College]

extro.ctim of soils to oo••er th� wo'-dr1 11£!1'1 Zea1on{l oo:U gt'Cllpa and found that tor many soUs, a more or lesn oonstnnt re.t:e ot extraation prevt'd.led �..er ihe seoon4 extraotia.le Wide Mft'ol:'Em)eB up to t'i£-ey told v.ll"'lo.ticn, uetooe tautld between ao1l gt'Ottps, with a � td.mil.nrit,y arr.rn.rent between the ourwa tor �ila ot the arunc genetic group. He grouped 'the eo Ug aooo:t"d:1n3 to h rate of �X>natant extrroticn mto h1Efl. mcclitn ood lol" to very low. nis 101'1 to \ler:'f lcw group

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Copper and zinc dynamics and bioavailability in soils amended with biosolids : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand

Copper and zinc dynamics and bioavailability in soils amended with biosolids : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand

extractants, depending on the strength, can extract various proportions of the total amounts of heavy metal in soil. The metal concentration extracted depends on the type of acid used and soil tested. Chelating agents and buffered salt solutions are believed to extract potentially mobile portions of metal in soil (Kabata-Pendias and Pendias 2001). EDTA is a well–known strong chelating agent widely used to predict plant–available heavy metal concentrations in soil (Alvarez et al. 2006; Saifullah et al. 2009). EDTA has been reported to remove metals that are organically bound, occluded in oxides, and associated with secondary clay minerals (Paya-perez et al. 1993). DTPA is another chelating agent commonly used to extract Cu and Zn from soil to estimate plant–available metal concentrations (Hammer and Keller 2002; Kabata-Pendias and Pendias 2001; Pastor et al. 2007). The amount of heavy metal extracted by such methods gives an idea of the index of potential toxicity or deficiency of metals, but interpretation of the results depends on consideration of the extractant used and the soil tested. For example, DTPA was developed for use on neutral to alkaline soils, and the relevance of the bioavailability index to plant under these conditions has been questioned (Hammer and Keller 2002). Degryse et al. (2004) suggested that EDTA extraction appears to be the most appropriate choice to approximate the labile metal content, when used at concentrations ranging between approximately 50 to 100 mmol EDTA per kg for any soil type. A lower concentration may not completely extract the labile amount, whereas a higher concentration will possibly release considerable amounts of the non–labile metal pool.

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Introduction of Medical Emergency Teams in Australia and New Zealand: a multi centre study

Introduction of Medical Emergency Teams in Australia and New Zealand: a multi centre study

Uptake of Medical Emergency Team (MET) services into those hospi- tals in Australia and New Zealand for which the MET status is known Uptake of Medical Emergency Team (MET) services into those hospi- tals in Australia and New Zealand for which the MET status is known. Each data point represents the cumulative total of MET services com- menced (y-axis) at the corresponding time (x-axis). The commencement of the MET service at Liverpool Hospital (University of New South Wales, Sydney, Australia) (June 1989) is omitted for the purpose of presentation. Shown below the x-axis are the first authors of publica- tions related to adverse events and METs: Lee, et al. [4]; McQuillan, etal. [16]; Smith and Wood [17]; Buist, et al. [14]; Goldhill, et al. [15]; Bristow, et al. [13]; Buist, et al. [6]; Hodgetts [21]; Foraida [22]; Bel- lomo, et al. [5]; and DeVita [7].

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BSMC : is there room for me? : an exploration of nursing leadership in primary health care : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy in Nursing at Massey University, Auckland, New Zealand

BSMC : is there room for me? : an exploration of nursing leadership in primary health care : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy in Nursing at Massey University, Auckland, New Zealand

In Frankel’s (2008) outline of leadership styles and characteristics a core function of nursing leadership is described as being a coach or mentor Furthermore, structured mentorship is described as the key to the acquisition and mastery of new skills, with mastery giving rise to a skill that is practiced repeatedly in order to achieve perfection. Hughes (2004) suggests terms to describe this leadership function of mentor are interchangeable and include, teacher, supporter, coach, facilitator, assessor, preceptor, role model and supervisor. This leadership characteristic of supporting those less skilful and less knowledgeable, especially in situations of change and innovation was also considered a crucial component to supporting staff development by Nelson, Wright, Connor, Buckley and Cumming (2009). They found on evaluating innovation projects in primary health care, the success related to the nursing leaders with effective communication and relational role modelling skills. Their analysis was significant given that the review was commissioned as a direct response to assessing progress toward achieving the aims of the primary health care strategy (Minister of Health, 2001). In this instance the characteristics of mentorship, advocacy and advice were seen as positive and necessary in crossing the contexts of clinical work, policy decision making, administrative and business procedure. These characteristics were especially useful when nurses were faced with system and resource constraints in contracting environments. Thus, to become effective resource managers, primary health care nurse leaders were seen to benefit from skilled communication ability at all levels of service provision.

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Response of soil invertebrates to pastoral management, and their links to soil services : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Manawatu, New Zealand

Response of soil invertebrates to pastoral management, and their links to soil services : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Manawatu, New Zealand

Nitrogen (N) fertilisation to boost pasture growth of the traditional phosphorus (P) fertilised legume based pastures, with symbiotic nitrogen fixation, is now a feature of New Zealand pastoral agriculture. The lift in pasture productivity has often been accompanied by an increase in stocking rate and associated treading pressures leading to soil compaction (Singleton and Addison 1999). Soil compaction can impact on the composition of soil faunal communities by altering the size distribution and connectivity of the pore space. This influences both the organisms that can inhabit the pores as well as their trophic interactions (King and Hutchinson, 1976; Elliott et al., 1980; Bouwman and Arts, 2000; Nielsen et al., 2008). In contrast, increased food supply associated with increased soil fertility often stimulates the abundance of soil invertebrates (Yeates, 1976; Cole et al., 2005; Curry et al., 2008), particularly bacterial feeding, plant feeding and plant associated nematodes (Yeates and Bongers, 1999). The use of crops (e.g., maize silage, brassicas) to supplement the feed of grass fed livestock increases the deposition of urine and dung to the soil surface, and therefore the supply of carbon and plant available nutrients to the soil plant system (Ruess and Seagle, 1994). Increased rates of nutrient cycling can influence organism life history, with short lived organisms becoming dominant (Bongers and Bongers, 1998; Coja and Bruckner, 2006). Interestingly, while N fertilised legume based pastures are more productive, with increases in the potential inputs of carbon (i.e., litter) into the soil, recent data by Schipper et al. (2007) suggests a trend for losses, rather than gains of soil carbon in New Zealand pastoral soils.

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Source-tracking cadmium in New Zealand agricultural soils: A stable isotope approach

Source-tracking cadmium in New Zealand agricultural soils: A stable isotope approach

Increasing soil organic carbon (SOC) may enhance sustainable production while offsetting greenhouse gas emissions from agriculture. Recent studies have suggested that infrequent full inversion tillage at pasture renewal (FIT-renewal) can help to accelerate SOC storage. Pastoral soils suited to respond positively to FIT-renewal show a contrasting vertical stratification of carbon that creates the opportunity to use deep ploughing to alter the depth-distribution of C-rich topsoil. Deep ploughing will both (1) transfer carbon-rich topsoil into the subsoil (slowing its decomposition), and (2) introduce litter and roots of the renewed pasture to the inverted subsoil (which is unsaturated in carbon). Changes in SOC storage and stratification need to be monitored closely due to spatial (paddock/farm scale) and temporal (over consecutive years) variability. Two field trial sites were set up in the Manawatu-Wanganui area, on a Pallic soil and on an Allophanic soil. Soils were deep ploughed (approx. 25 cm) and re-sown with turnip as a summer crop; other treatments included were shallow (5 cm) till and no till. The site was core sampled (0-40 cm) before cultivation and after 5 months of turnip growth to assess changes in SOC and stratification by using (1) laboratory-based analytical methods and (2) proximal sensing methods. At each site, deep cultivation transferred SOC below 10 cm depth, as expected. This one-time deep ploughing event did not homogenise the soil profile at the paddock level, but created a complex lateral variability instead. The hyperspectral reflectance scanning of the cores allows the soil carbon profile to be described in greater resolution by depth allowing researchers to make choices about the plough settings used prior to FIT-renewal. The information gained brings the application of FIT-renewal closer to widespread on- farm use in New Zealand by informing farmers on soil tillage history.

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Copper and zinc dynamics and bioavailability in soils amended with biosolids : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand

Copper and zinc dynamics and bioavailability in soils amended with biosolids : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand

A laboratory incubation trial with Cu– and Zn– spiked biosolids added to eight soils representing the major Soil Groups collected from across the North Island of New Zealand (biosolids added to give final soil concentrations of 150 mg/kg for Zn or 450 mg/kg for Cu), showed that crystalline Fe oxide was the dominant factor explaining 90% of the variability in exchangeable Cu. For Zn, clay content and pH were the controlling soil factors that together explained 73% of the variability in exchangeable Zn. An increased content of crystalline Fe oxide increased the soil exchangeable Cu concentration. Decreasing pH and increasing clay content increased the soil exchangeable Zn concentration.

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Variability in δ15N, δ13C and Kjeldahl nitrogen of soils from islands with and without seabirds in the Marlborough Sounds, New Zealand

Variability in δ15N, δ13C and Kjeldahl nitrogen of soils from islands with and without seabirds in the Marlborough Sounds, New Zealand

It is likely that nitrogen was not limiting on any of the islands studied. The percent nitrogen was as great as that found on other seabird-influenced sites around the New Zealand coast (Leamy and Blakemore, 1960; Atkinson, 1964) and lower than that found around nests in a gannet colony (Blakemore and Gibbs, 1968). Although greater than for most grassland soils (e.g. Brevedan et al., 1996), the nitrogen level of soils from Marlborough Sounds islands was well within the range of percent nitrogen in forest soils from around the world (Vitousek et al., 1982; Pastor et al., 1984). In many cases past work that has shown significant effects of seabirds on soil nitrogen took place at sites with relatively low productivity in the absence of seabirds, e.g. Antarctica (Mizutani and Wada, 1988; Ryan and Watkins, 1989), sub-Antarctic islands (Burger, 1978) or the desert islands of Baja California (Polis and Hurd, 1996b; Anderson and Polis, 1998, 1999; Stapp et al., 1999). Stable isotope analysis shows that although there is marine input into the islands in this study, the soils are still predominantly terrestrially derived. It can be concluded that in the relatively productive islands of the Marlborough

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A provisional assessment of risk associated with heavy metal accumulation in New Zealand agricultural soil: Effects of landfarming and fertiliser use on the heavy metal concentrations in plants : A thesis presented in partial fulfilment of the requirement

A provisional assessment of risk associated with heavy metal accumulation in New Zealand agricultural soil: Effects of landfarming and fertiliser use on the heavy metal concentrations in plants : A thesis presented in partial fulfilment of the requirements for the degree of Masters of Environmental Management (without major) at Massey University, Manawatu, New Zealand

This study investigated heavy metal accumulation in New Zealand agricultural soil (horticultural soil and landfarm-impacted soil), factors influencing their concentration in leafy vegetables and pasture, and the potential implications to food safety, animal welfare and human welfare. The study also sought to verify the hypothesis that “landfarming poses no threat to pasture and animal welfare” with respect to heavy metal accumulation. In addition, hemp phytoremediation potential was also explored for landfarm-impacted soil.

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Apiianga no te oraanga akapuapinga e te taporoporo i te ipukarea : education as sustainable development : Mangaia, Cook Islands : a dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Development Stud

Apiianga no te oraanga akapuapinga e te taporoporo i te ipukarea : education as sustainable development : Mangaia, Cook Islands : a dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Development Studies, Massey University, Palmerston North, New Zealand

I owe my wonderful supervisor’s Doctor Rochelle Stewart-Withers, Professor Huia Jahnke and Professor Regina Scheyvens a debt of gratitude. I am grateful to you all for your professionalism and the challenging conversations you engaged me in. You patiently encouraged me and diligently supported me throughout the thesis. You inspire me with your passion for development studies and indigenous education. I thank The New Zealand Aid Programme and the Massey University People, Environment and the Planning

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