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    On the trajectory of discrimination: A meta-analysis and forecasting survey capturing 44 years of field experiments on gender and hiring decisions
    (Elsevier Inc, 2023-11) Schaerer M; Plessis CD; Nguyen MHB; van Aert RCM; Tiokhin L; Lakens D; Clemente EG; Pfeiffer T; Dreber A; Johannesson M; Clark CJ; Uhlmann EL; Abraham AT; Adamus M; Akinci C; Alberti F; Alsharawy AM; Alzahawi S; Anseel F; Arndt F; Balkan B; Baskin E; Bearden CE; Benotsch EG; Bernritter S; Black SR; Bleidorn W; Boysen AP; Brienza JP; Brown M; Brown SEV; Brown JW; Buckley J; Buttliere B; Byrd N; Cígler H; Capitan T; Cherubini P; Chong SY; Ciftci EE; Conrad CD; Conway P; Costa E; Cox JA; Cox DJ; Cruz F; Dawson IGJ; Demiral EE; Derrick JL; Doshi S; Dunleavy DJ; Durham JD; Elbaek CT; Ellis DA; Ert E; Espinoza MP; Füllbrunn SC; Fath S; Furrer R; Fiala L; Fillon AA; Forsgren M; Fytraki AT; Galarza FB; Gandhi L; Garrison SM; Geraldes D; Ghasemi O; Gjoneska B; Gothilander J; Grühn D; Grieder M; Hafenbrädl S; Halkias G; Hancock R; Hantula DA; Harton HC; Hoffmann CP; Holzmeister F; Hoŕak F; Hosch A-K; Imada H; Ioannidis K; Jaeger B; Janas M; Janik B; Pratap KC R; Keel PK; Keeley JW; Keller L; Kenrick DT; Kiely KM; Knutsson M; Kovacheva A; Kovera MB; Krivoshchekov V; Krumrei-Mancuso EJ; Kulibert D; Lacko D; Lemay EP
    A preregistered meta-analysis, including 244 effect sizes from 85 field audits and 361,645 individual job applications, tested for gender bias in hiring practices in female-stereotypical and gender-balanced as well as male-stereotypical jobs from 1976 to 2020. A “red team” of independent experts was recruited to increase the rigor and robustness of our meta-analytic approach. A forecasting survey further examined whether laypeople (n = 499 nationally representative adults) and scientists (n = 312) could predict the results. Forecasters correctly anticipated reductions in discrimination against female candidates over time. However, both scientists and laypeople overestimated the continuation of bias against female candidates. Instead, selection bias in favor of male over female candidates was eliminated and, if anything, slightly reversed in sign starting in 2009 for mixed-gender and male-stereotypical jobs in our sample. Forecasters further failed to anticipate that discrimination against male candidates for stereotypically female jobs would remain stable across the decades.
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    Comparison of two methods of herbage production measurement in continuously grazed hill pastures : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey University
    (Massey University, 1995) Hawkins, Clive Leo
    Herbage production of continuously grazed hill country pastures has traditionally been measured using grazing exclusion cages and a trim technique. Herbage production values obtained via this system differ from those of the surrounding grazed sward due to differences in sward structure. Herbage production of four farmlets with differing fertiliser treatments was measured by two methods over a full year. The first method involved a computer model which calculated herbage production from dry matter intake and cover change. Secondly, herbage production was measured via frame cuts, and the results of the two methods compared. The model measured less herbage production than the frames on an annual basis in all four fertiliser treatments (0.77 of frame average for the four fertiliser treatments). The ratio of model to frame herbage production varied widely during the year, with maximum ratios of model to frame herbage production of 1.6 occurring in autumn, and the minimum of -0.02 in winter. More herbage was produced under the frames in spring than in the grazed sward as a result of increased expression of reproductive tillers under the frames than in the grazed sward. Frames appear to underestimate herbage production in dry conditions as the trimming off of herbage at the placement of frames leads to lower levels of plant available water when compared to the surrounding sward. The low ratios are a result of the large amounts of dead material which build up in grazed hill pastures over summer and the rapid breakdown of this material when conditions are right, in this case in early-late winter. The results suggest that there are large differences in the annual, and seasonal pattern of herbage production between that measured off grazed swards and that measured via frames. This suggests that anyone wishing to calculate expected pasture supply using frame cut information must modify frame cut values to determine production of a continuously grazed sward.
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    Effects of nitrogen fertiliser on the growth, development and yield of maize (Zea mays L.) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Science
    (Massey University, 1974) Thom, Errol Ross
    Maize has been grown in New Zealand for over a century. The traditional grain growing district has been Gisborne, where suitable environmental conditions prevail. Over recent years there has been a rapid expansion of maize production for grain, silage and greenfeed. For example, in the 1970/71 season (NZMAF estimates), 12,000 hectares of maize was grown for grain while in 1962/63 only about 3,000 hectares were grown; in the 1971/72 season 18,600 hectares were involved in grain production. Respective estimates for the 1972/73 and 1973/74 seasons were 16,300 and 17,800 hectares. Furthermore maize growing has now extended far beyond Gisborne with the Waikato, Bay of Plenty and Hawkes' Bay districts being regarded as major grain producing areas of New Zealand. Further south in the Manawatu and Canterbury high yielding crops of maize are also being grown for silage and greenfeed under suitable environmental conditions. Along with the upsurge in maize growing in these districts there has been the need for more agronomic information (Gooding, 1972) on the yield response, in terms of grain and total dry matter production; on the appropriate rate of nitrogen application and on the timing of the application for maximum response under the prevailing environmental conditions. With more maize being utilised in intensive animal production enterprises (Jagusch and Hollard, 1974) the quality of the dry matter produced assumes greater importance.
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    Field and laboratory studies of the movement and reactions of phosphorus in soils : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University
    (Massey University, 1978) Rennes, Alexander Marinus Dick
    Low and stable concentrations of phosphorus (P) forms and sediment were obtained in stream flow from two small, adjacent, scrub-covered, and minimally-disturbed catchments near Palmerston North, New Zealand. In contrast, higher and irregular concentrations and loadings were obtained following land clearing, P fertilizer application, and the establishment of grazed pasture. The need for intensive stream sampling, as well as complete hydrograph data in order to obtain reliable information on stream loadings, is emphasised. High and fluctuating concentrations of P forms and sediment were obtained following the change in land use. A high proportion of the P and sediment loss occurred in the storm runoff component of stream flow. The estimated losses of fertilizer P in stream flow (approximately 1% of that added) were very small from an agronomic standpoint but they represent large proportional increases in the loadings of P forms in stream flow. The high amounts of water-extractable P present in the soils of the catchment (field soils), immediately following the aerial application of fertiliser P, declined rapidly to lower, more stable values. This pattern of decline for field soils was replicated using small pots established in the field (pot soils) and containing fertilized soil representative of the catchments. Close correlations were obtained between water-extractable P in the upper 1cm of field and pot soils, and mean dissolved inorganic P (DIP) concentrations in the surface runoff component of stream flow in closely-following storms. The possibility of predicting DIP losses in surface runoff from soils using a water-extraction technique is thus indicated. The decrease with time in the amounts of water-extractable P observed after superphosphate addition to field and pot soils was reproduced in the laboratory. This relationship validated the use of laboratory studies to examine the rate and extent of interaction of fertilizer P occurring in field soils and to predict the potential movement of fertilizer P from soils to waters. The decline in water-extractable P closely paralleled the decrease in plant uptake of P with time following fertilizer P addition to two constrasting soils. This suggested that water extraction may be a useful soil-testing procedure for predicting P availability to plants, as well as the movement of P in surface runoff from soils. The rate of decline in water-extractable P in a given soil was proportional to both the amount of P added and the amount initially extractable immediately following P addition. This suggests that the rate and extent of P sorption in a soil is directly related to soil solution P concentration. Differences were obtained, however, between three contrasting soils in the relative rate and extent of P sorption. A kinetic model based on the Langmuir equation was developed to simulate the decline in water-extractability of P added to three soils. Three populations of sites were assumed and the appropriate sorption maxima and binding energy constants were derived from sorption isotherm studies. The model provided a satisfactory prediction of the fate of different amounts of fertilizer P. It is probable that the further development of this model would provide a useful basis for predicting the fate of P added to soils and the potential movement of added P in surface-runoff waters.
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    Environmental and plant factors causing low legume seedling establishment following oversowing into drought-prone hill swards : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph.D.) in Plant Science at Massey University, New Zealand
    (Massey University, 1995) Awan, Manzoor-ul-Haque
    Legumes are a valuable component of pastures since they tend to have higher feed quality than grasses and can also fix atmospheric nitrogen in the soil. The technology for oversowing legumes has had many improvements but the success rate is poor and the legume contribution to hill country pasture production remains low. It was concluded that unpredictable weather and plant factors were the major factors causing poor pasture legume establishment from oversowing. To determine the environmental and plant factors responsible for poor pasture legume establishment from oversowing, a series of seven trials were carried out at AgResearch, Poukawa near Hastings. The five annual and seven perennial legume species oversown in order of establishment success were; subterranean clover (Trifolium subterraneum), barrel medic (Medicago trunculata), birdsfoot trefoil (Lotus corniculatus), white clover (T. repens), strawberry clover (T. fragiferum), murex medic (M. murex), arrow leaf clover (T. vesiculosum), lucerne (M. sativa), alsike clover (T. hybridium), persian clover (T. resupinatum), Maku lotus (L. pedunculatus) and caucasian clover (T. ambiguum). Seeds of each species were oversown in autumn, winter and spring, following defoliation with glyphosate and trodden with sheep. The greatest loss of potential seedlings after oversowing was non-appearance of seedlings, which accounted for about 80% of viable seed. Overall, the contribution of sown legume species to total herbage mass was less than 12% and seedling establishment success was typically between 5 and 30%. The relationships between eight environmental factors and seedling establishment were explored and the main influences on establishment were found to be gravimetric soil water content, soil temperature, minimum air temperature and daily wind run. A simple model based on these four factors was developed from the field trial data and extrapolated to 10 years of Lawn Road, Hastings and 5 years of Poukawa climate data and the best time, on average, for oversowing was predicted. To test the effect of high, medium and low soil surface moisture and also to find out the fate of oversown seed two experiments were carried out in a glasshouse using caucasian, strawberry and subterranean clovers. A simple and cheap technique based on CoCl2 saturated paper strips was developed to measure the changes in soil surface moisture. The soil moisture at depth was a poor indicator of seed germination compared with the surface soil moisture. The low soil surface moisture gave lowest seedling survival. The main cause of low soil surface was wind run. The percentage of ungerminated seed was significantly higher for oversowning than to the standard seed germination test. Two trials were carried out at AgResearch, Ballantrae, to test the effect of seed rate and seed size. It was observed that sowing rates greater than those usually recommended would increase the seedling density and legume contribution to the total herbage mass and might produce more seed for re-establishment of annual legumes in the subsequent years. Seed size did not significantly affect establishment. The effect of seed coating and seed dressing was also monitored in a trial at Poukawa. The seed of subterranean and white clovers dressed with fungicide, insecticide and two commercial seed coatings were compared with bare seed. The commercial seed coating increased the early seed germination by 30% but not the final seedling density compared with bare seed. Apron fungicide seed dressing had a deleterious effect on seed germination. The effect of glyphosate residue and litter phytotoxicity was tested in a glasshouse experiment with birdsfoot trefoil and subterranean and white clovers. The species were oversown onto sods sprayed with glyphosate 20 days earlier and onto ordinary sand. The glyphosate residue and dead material did not have any major effect on seed germination and seedling survival. Overall, environmental factors were found to be the key determinants of successful establishment for pasture legumes by oversowing. Both, the likely environmental conditions at the time of oversowing, and during the first few months of seedling growth need to be considered. The establishment of legume species suited to oversowing can be improved by using high sowing rates and seed coating but ultimately it is the moisture level and temperature at the soil surface that determines germination, and wind run and minimum air temperature that determines seedling survival in drought-prone hill swards.