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The New Zealand Fertilizer Industry- A Vital Cog In The Pasture Production Cycle, M J. Hickey, T Johnston 2024 FERNZ Corporation Ltd

The New Zealand Fertilizer Industry- A Vital Cog In The Pasture Production Cycle, M J. Hickey, T Johnston

IGC Proceedings (1977-2023)

The New Zealand fertiliser industry is geared mainly to meet domestic demand, The main fertiliser applied is single superphosphate supplying both sulphur and phosphorus, These elements are required on most New Zealand soils. White clover (Trifolium repens L.) provides most of the nitrogen requirements by symbiotic production. Fertiliser applications are currently 1.S-1.6 million t, of which 9091, is used for livestock production, supporting SB million sheep, 4.6 million beef cattle and 3.S million dairy stock. Fertiliser sales peaked at 2.S million t in 1979 and have fallen as economic conditions deteriorated in the 1980s, coupled with removal of all …


Behavior Of Goats And Sheep On An Eroded Hill Country Pasture In Winter, L A. Greaves, M E. Wedderburn 2024 AgResearch, NZ

Behavior Of Goats And Sheep On An Eroded Hill Country Pasture In Winter, L A. Greaves, M E. Wedderburn

IGC Proceedings (1977-2023)

The behaviour of cashmere-producing does was compared with that of Romney ewes on an area of surface erosion in pasture-dominated hill country during winter. Five ewes and 5 does were monitored. Each group was observed for 4 days, during June-July, from dawn to dusk. A fixed, remote video camera was used to record the animals' behaviour. Tapes were later analysed, noting animal activity, position and time. Bwes spent 13% of their day on the eroded surfaces compared to 2% for the does, Does were observed on the erosion mainly in the afternoon, whereas the ewes were present at all stages …


Effects Of Lime And Phosphate Applications On Growth And Nitrogen Fixation Of Alfalfa In Acid Soils, Chun Woo-Bock, Ki-Chun Choi, Jung-Chul Kim, Kwang-Hyun Kim, Dong-Hoo Kim 2024 Chonnam National University

Effects Of Lime And Phosphate Applications On Growth And Nitrogen Fixation Of Alfalfa In Acid Soils, Chun Woo-Bock, Ki-Chun Choi, Jung-Chul Kim, Kwang-Hyun Kim, Dong-Hoo Kim

IGC Proceedings (1977-2023)

The effects of applications of various levels of lime (0, 250, 500 and 1000 kg/10 a) and phosphate (0, 17, and 34 kg/10 a) on growth and on nitrogen fixation of alfalfa (Medicago sativa L.) were studied. Effects of lime and phosphate applications were significantly different on dry mailer (DM) weight of each part and on acetylene reduction activity (ARA) of alfalfa al 9 weeks after sowing (P<0.05). The effect of lime on DM of shoot and root was not significantly different at 14 weeks after sowing (early bloom) but that of phosphate was significantly greater as levels increased (P<0.0 1). The effects of lime and phosphate on ARA were significantly increased (P<0.05), Nine weeks after sowing, application of lime and phosphate decreased total N content of each part of alfalfa compared with no application (P<0,05). At 14 weeks after sowing lime application increased total N content and phosphate decreased total N content, compared with not application (P<0.05).


Effects Of Subsoiling On A Northern Podzol Soil, M A. Richardson, C R. Edwards 2024 AgResearch, NZ

Effects Of Subsoiling On A Northern Podzol Soil, M A. Richardson, C R. Edwards

IGC Proceedings (1977-2023)

Subsoiling is a method of mechanical loosening that can improve water movement through soil. It has been evaluated on a poorly drained northern podzol soil in paddock scale trials over three years. Subsoiling with a tractor drawn implement at 500 mm depth resulted in consistent reductions in surface water contents and lowered water tables. Pasture production was significantly increased in two of the three years and favourable pasture composition changes occurred, Root distribution in winter was also affected, with significant increases in root density between· JOO and 300 mm depth. Recompaction occurred during winter grazing and paddocks required re-subsoiling each …


Predicting The Leaching Of Sulphur Fertilizer On Yellow-Brown Pumice Soils, B S. Thorrold, K C. Cameron 2024 AgResearch, NZ

Predicting The Leaching Of Sulphur Fertilizer On Yellow-Brown Pumice Soils, B S. Thorrold, K C. Cameron

IGC Proceedings (1977-2023)

Leaching of sulphate can have a major influence on pasture yield and fertiliser efficiency on the yellow-brown pumice soils of New Zealand. This study aimed to measure and predict sulphur (S) leaching on these soils. The Rose model (an approximate analytical method based on the convective-dispersive equation) accurately simulated S leaching data from intact cores when a retardation factor was included to allow for sulphate adsorption, The model was then used to predict the leaching of sulphate or elemental S fertilisers applied in spring or autumn. Predicted amounts leached below 260 mm depth after 12 months were 91, 71, 38 …


Quantification Of Oxidation Of Elemental Sulphur In Pastoral Soils Of New Zealand, A Ghani, A Lee, J H. Watkinson, C Boswell, B S. Thorrold, J D. Moryon, M P. Upsdell 2024 AgResearch, NZ

Quantification Of Oxidation Of Elemental Sulphur In Pastoral Soils Of New Zealand, A Ghani, A Lee, J H. Watkinson, C Boswell, B S. Thorrold, J D. Moryon, M P. Upsdell

IGC Proceedings (1977-2023)

A cubic model to describe elemental sulphur (S) oxidation as proposed by Watkinson (1989) was tested under field conditions. Trials were conducted throughout New Zealand to examine the effects of climate, particle size and frequency of application on the rate of S oxidation. Elemental S (75-1S0 mm size) was added to duplicate plots at a rate of 30 kg/ha. Soil samples (0-38 mm) were collected regularly for determining the amounts of added elemental S remaining in the soil. The results showed that the oxidation of elemental S could be adequately described by the cubic model, Por most sites it explained …


Effectiveness Of Sulphate And Elemental Sulphur Fertilizers Applied To Pastures In Autumn Or Spring, S F. Ledgard, B S. Thorrold, M S. Sprosen, M F. Hawke 2024 AgResearch, NZ

Effectiveness Of Sulphate And Elemental Sulphur Fertilizers Applied To Pastures In Autumn Or Spring, S F. Ledgard, B S. Thorrold, M S. Sprosen, M F. Hawke

IGC Proceedings (1977-2023)

Uptake of elemental sulphur {S, 50% 75-150 µm and 50% 150-250 µm diameter) or sulphate (applied as gypsum) by pasture in the field was examined using 3 rates of application in autumn or spring on 2 low S­retentive soils; u free-draining pumice soil and a slow-draining gley soil. About 90% of the el��mental S was oxidised to plant-available sulphate during I year after application. On the pumice soil, the apparent recovery of added S was greatest from autumn-applied elemental S. Leaching appeared to reduce the effectiveness of sulphate fertiliser. On the gley soil, sulphate was more effective in enhancing pasture …


Lysimeter Study Of The Fate Of Nitrogen In Animal Urine Applied To Flood-Irrigated Pasture, K C. Cameron, P M. Fraser 2024 Lincoln University

Lysimeter Study Of The Fate Of Nitrogen In Animal Urine Applied To Flood-Irrigated Pasture, K C. Cameron, P M. Fraser

IGC Proceedings (1977-2023)

The fate of nitrogen (N) in animal urine returns to flood irrigated pasture was studied using large soil monolith lysimeters (800 nun diameter x 1200 mm deep). Over a period of I year, the largest fraction of applied 15N (44%) was recovered by the pasture plants. The total amount (42 kg N/ha) and average peak concentration of N, in the leachate (42 µgN/ml) were less than values reported for many: other agricultural situations (e.g., ploughed pasture). The amount of N lost by denitrification was high (28% of applied 15N) and attributed to the wet soil conditions which prevailed. The amount …


Estimating Fertilizer Substitution Values From The Dissolution Rates Of Reactive Phosphate Rocks In New Zealand Pastoral Soils, J H. Watkinson, K W. Perrott 2024 AgResearch, NZ

Estimating Fertilizer Substitution Values From The Dissolution Rates Of Reactive Phosphate Rocks In New Zealand Pastoral Soils, J H. Watkinson, K W. Perrott

IGC Proceedings (1977-2023)

A relationship is developed between the substitution value of reactive phosphate rock (RPR) relative to triple superphosphate (TSP), both applied annually to pasture, and the dissolution rate of the RPR. The residual effect of dissolved phosphate is included. Residual RPR is calculated from the dissolution rate of the RPR in the soil, while residual phosphate from TSP or dissolved RPR is taken as a constant fraction of the value in the previous year. Calculations including the residual effect of dissolved fertiliser produce smaller substitution values and longer lag times for RPR than when the effect is omitted. The relationship derived …


Field Evaluation Of Perennial Ryegrass Selected For Aluminum Tolerance On Fertile Soils, D M. Wheeler, D R. Smith, D C. Edmeades 2024 AgResearch, NZ

Field Evaluation Of Perennial Ryegrass Selected For Aluminum Tolerance On Fertile Soils, D M. Wheeler, D R. Smith, D C. Edmeades

IGC Proceedings (1977-2023)

The progeny from 23 perennial ryegrass (Lolium perenne L.) plants which were selected for aluminium (Al) tolerance using a low ionic strength nutrient culture technique, were grown in nursery and field trial, to evaluate the agronomic performance in a fertile soil (i.e., in the absence of stress), There were no differences between the progeny from the Al-tolerant selected plan1s in the lines with low Argentine stem weevil (Listronotus bonariensis) damage and commercial cultivars in the nursery trial. There were also no differences in dry matter yield between an Al selection line consisting of seed bulked from 2 …


Use Of Ld (Linz-Donawitz) Slag As A Liming Material In The Basque Country (Spain): Effect On Chemical Composition Of Pastures, M Pinto, M Rodriguez, C Trueba 2024 Servicio de Investigacion y Mejora Agraria

Use Of Ld (Linz-Donawitz) Slag As A Liming Material In The Basque Country (Spain): Effect On Chemical Composition Of Pastures, M Pinto, M Rodriguez, C Trueba

IGC Proceedings (1977-2023)

LD (Lintz-Donawit:i:) slag is an iron industry by-product generated at a rate of 10 million I/year in Europe. Its chemical composition (45% Cao and 8% Mg2O) seemed to indicate that a good way of re­utilisation of this waste would be Its use as a corrector of pH for acid soils. The slag effect on chemical composition and yield has been studied in grasslands in the Basque Country during a 2-year field trial. Two different pastures have been considered, Derio (pH 4.75), a resown loliwn pere1me-Trifoli11m repens pasture, and Abadiano (pH 5.45), a natural prairie. Previous studies have shown that slag …


Effect Of Inorganic Nitrogen And Cow Slurry On Yield And Nitrogen Losses In A Natural Pasture In The Basque Country (Spain), J M. Esta Villo, C Gonzalez-Murua, M Rodriguez 2024 Universidad del Pais Vasco

Effect Of Inorganic Nitrogen And Cow Slurry On Yield And Nitrogen Losses In A Natural Pasture In The Basque Country (Spain), J M. Esta Villo, C Gonzalez-Murua, M Rodriguez

IGC Proceedings (1977-2023)

Inappropriate use of fertilisers can cause large losses of nitrogen (N) from the system with different ecological consequences. This study tried to make a first approach to N cycling by comparing N inputs and outputs in an imperfectly drained natural grassland soil receiving different rates of N fertiliser as ammonium nitrate or cow slurry, The acetylene inhibition technique· is used for measuring denitrification, Fertiliser response and decrease in white clover (Trifolium repens) content was greater for the inorganic treatment. The highest rates of denitrification occurred when nitrate and soil water were high. Losses in the inorganic treatment were …


Effect Of Fertilizer Application On Soil Organisms Under Pasture, K W. Perrott, S U. Sarathchandra, A Lee 2024 AgResearch, NZ

Effect Of Fertilizer Application On Soil Organisms Under Pasture, K W. Perrott, S U. Sarathchandra, A Lee

IGC Proceedings (1977-2023)

Effects of nutrients and phosphate fertiliser on soil microbial biomass and several groups of soil organisms were determined in a glasshouse and field experiment. Extreme depletion of soil phosphorus nitrogen or sulphur caused a decline in the soil microbial biomass. This appeared to result from lower plant growth rather than directly through nutrient depletion. No long-term effects of superphosphate (SSP) or North Carolina phosphate rock (NCPR) on numbers of earthworms or soil micro-organisms were found in a field experiment where treatment differences had been maintained for 3 years. However, soil samples taken from fertilised plots 14 days after topdressing had …


Cadmium Accumulation In New Zealand Pastoral Agriculture, A.H C. Roberts, R D. Longhurst, M W. Brown 2024 AgResearch, NZ

Cadmium Accumulation In New Zealand Pastoral Agriculture, A.H C. Roberts, R D. Longhurst, M W. Brown

IGC Proceedings (1977-2023)

The accumulation of cadmium (Cd) in New Zealand agriculture was investigated principally in a national survey of pastoral soils. A total of 398 sites were sampled covering most major provinces in both North and South Islands: 312 pastoral farms and 86 "native" sites. The native sites were native bush, reserves, parks or other non­agricultural areas which were representative of the soil groups sampled on farms, The overall average total Cd content (0-7.5 cm depth) for native soils was 0.20 µgig Cd (range 0.02-0,77 µgig Cd), while the corresponding average content for pastoral soils was 0.44 µgig Cd (0.04-1.53 µgig Cd). …


Use Of Forage Nitrate-Nitrogen To Improve Nitrogen-Use Efficiency In Coastal Bermudagrass, S R. Wilkinson, M H. Frere 2024 USDA, Agricultural Research Service

Use Of Forage Nitrate-Nitrogen To Improve Nitrogen-Use Efficiency In Coastal Bermudagrass, S R. Wilkinson, M H. Frere

IGC Proceedings (1977-2023)

Coastal bermudagrass (Cynodon dactylon L. Pers.) is an important warm-season perennial grass in the Southern Piedmont of the USA. It has a high production potential, a consequent high N fertiliser requirement and is often recommended as cover for waste management systems. Forage NO3-N was correlated with dry matter yield, and drainage water with NO3-N concentration. Log forage NO3-N was significantly correlated with yield (R2=0,83) and with log soil water NO3-N (R2 .. 0.76) (P<0.01). Yields of bermudagrass associated with accumulation of IO mg NO3-N/I in shallow ground water were less than 75% of maximum, Bermudagrass growth modelling studies suggest that about 50% of maximum yield is the point of greatest N­use efficiency. This may approximate the upper limit of N application for the long term if excessive NO3-N concentration in shallow ground water Is to be prevented. Forage tissue testing for NO3-N may be useful for indicating when N-use efficiency is declining and when excess NO3-N accumulation in the soil may be expected.


Continuous High Production In The Meadow By Introduction Of Seasonal Grazing, H Murakami, H Iwama, K Okamoto 2024 National Grassland Research Institute

Continuous High Production In The Meadow By Introduction Of Seasonal Grazing, H Murakami, H Iwama, K Okamoto

IGC Proceedings (1977-2023)

Two meadows were equally fertilised and used for haymaking since their establishment in 1966. The dry matter (DM) yield decreased gradually after the establishment of the meadows and reached a stable low level around 1974, when the autumn-saved pasture (ASP) winter grazing system was introduced to one of them !ASP meadow). The productivity of the meadow for only haymaking (HM meadow) remained low (9 t/ha), whereas the productivity of the ASP meadow recovered rapidly to a high level (13 Uha). DM yield and nutrient absorption by grass in the ASP meadow (N:242, P2O5:97, K1O:412 kg/ha) were about 1.5 times as …


Correspondence Between Vegetation And Soil In An Open Grassland, K Torok 2024 Institute of Ecology and Botany of the Hungarian Academy of Sciences

Correspondence Between Vegetation And Soil In An Open Grassland, K Torok

IGC Proceedings (1977-2023)

Within the framework of a project to assess the condition of the communities in a nature reserve, soil variables were compared to vascular species composition of 3 andesite grassland sites. Fifty-five plots were sampled for species cover and for 17 soil variables, Characteristic indicator values (CIV) of each relev6 was also calculated for temperature, moisture, reaction and nitrogen based on species ecological indicator values. In this way 3 data sets have been subjected to multivariate analyses in order to detect dissimilarity among sites. The results show that the measured soil variables have an impact upon species composition: the stands are …


Fate Of Urinary Nitrogen On Peat Soils Under Contrasting Conditions, T J. Clough, S F. Ledgard, K C. Cameron, R R. Sherlock 2024 AgResearch, NZ

Fate Of Urinary Nitrogen On Peat Soils Under Contrasting Conditions, T J. Clough, S F. Ledgard, K C. Cameron, R R. Sherlock

IGC Proceedings (1977-2023)

In the Waikato district of New Zealand, large areas of peat soils are used for pastoral agriculture. This study examined the urinary nitrogen (N) transformations after application of ISN•labelled urine to peat soils at 2 stages of development, with and without a water table present. The peat soil with the longest development history had greater plant recovery of urine N but also had greater denitrificalion losses. The presence of a water table reduced both immobilisation and plant uptake of urinary N and increased loss by denitrification.


Studies On Soil Microbial Biomass Carbon, Nitrogen And Phosphorus In Three Crop Rotation Systems, A Garcia, D A. Moron 2024 INIA

Studies On Soil Microbial Biomass Carbon, Nitrogen And Phosphorus In Three Crop Rotation Systems, A Garcia, D A. Moron

IGC Proceedings (1977-2023)

Amount and dynamics of microbial biomass were studied in 3 different agricultural systems which has been cropped for 27 years on a mollisol. Plots were sampled 5 times between June 1989 and January 1990, Average microbial biomass was higher in the pasture-crop system than in the continuous crop system, Seasonal variations in biomass were related to periods of active plant growth and warmer temperatures. Quantities of nitrogen (N) and phosphorus (P) immobilised in soil biomass were also higher in the crop pasture system and were linearly related to biomass carbon. Mean annual fluxes through biomass (20 cm depth) were estimated …


Field Evaluation Of Partially Acidulated Phosphate Rocks As Fertilizers For Permanent Pastures, S.S S. Rajan, S F. Ledgard, B S. Thorrold 2024 AgResearch, NZ

Field Evaluation Of Partially Acidulated Phosphate Rocks As Fertilizers For Permanent Pastures, S.S S. Rajan, S F. Ledgard, B S. Thorrold

IGC Proceedings (1977-2023)

Seven field trials were conducted, in soils of volcanic origin, to evaluate the agronomic effectiveness of partially acidulated phosphate rocks (PAPRs), as influenced by type of acidulant, degree of acidulation, fineness of grinding and reactivity of phosphate rock, and hardness of the granules, Pasture dry matter production results indicated that sulphuric PAPRs of 30% and SO% acidulation prepared from unground North Carolina rock were less effective than superphosphate. When reactive rocks were finely ground, 20% phosphoric acidulated product was generally as effective as superphosphate, and there was no apparent difference between the products prepared from North Carolina and a less …


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