Estimating Fertilizer Substitution Values From The Dissolution Rates Of Reactive Phosphate Rocks In New Zealand Pastoral Soils,
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,
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,
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),
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,
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,
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,
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,
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,
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,
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,
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,
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 …
Improving The Efficiency Of Nitrogen Utilization In A Grassland Soil With Different Mixtures Of Pasture Species, B E. Ruz-Jerez, P Roger Ball, R E. White
IGC Proceedings (1977-2023)
Pasture composition, herbage yield and symbiotic nitrogen fixation were compared in traditional grasslands (either based on fertiliser N or legumes) and a grassland system (herbal Icy) based on a mixture of legumes, non-aggressive grasses and deep-rooting herbs. Herbal Icy was the most efficient system in terms of herbage production per unit of N input, offering the possibility of sustaining a high level of pasture production without fertiliser N and hence reducing the risk of N losses to the environment.
Pasture Sulphur Recovery And Transformations Of Sheep Urinary Sulphur In Irrigated Soils Of Canterbury, New Zealand,
2024
Lincoln University
Pasture Sulphur Recovery And Transformations Of Sheep Urinary Sulphur In Irrigated Soils Of Canterbury, New Zealand, M L. Nguyen, K M. Goh
IGC Proceedings (1977-2023)
A field plot trial was conducted on irrigated pasture of a Templeton silt loam soil (Udic Ustochrept) by applying 3Ssulphur (358)-labelled urine (250 µCi/g S with 1300 µSimi urine) to field plots (600x600 mm) at a rate normally occurring in sheep urine patches (150 ml in 0.03 m1). Results showed that 27 days after urine application, approximately 55- 90% of 35S-labelled urine was incorporated into soil sulphate (SO4)-S, ester SO 4-S and carbon-bonded S fractions within the major rooting zone (0-300 mm), Labelled-S was found to a soil depth of 500 cm during a 271-day period, showing that these S …
Factors Affecting Plant Sulphur Requirements In New Zealand Pastoral And Arable Systems,
2024
Lincoln University
Factors Affecting Plant Sulphur Requirements In New Zealand Pastoral And Arable Systems, M L. Nguyen, K M. Goh
IGC Proceedings (1977-2023)
This paper reviews major factors affecting sulphur (S) cycling in New Zealand pastoral and arable· systems and identifies areas of research required to improve the efficient use of S fertilisers and soil S reserves. In the grazed pastoral system, S removal in animal products constitutes a small fraction of total S output while S leaching losses and excreta! S transfer losses to stock camps are substantial. Although grazing animals may cause a considerable S loss from the system, they enhance the oxidation of elemental S. Accumulated soil organic S due to the return of animal excreta and long-term annual applications …
An Overview Of Pasture Response, Nutrient Turnover And Nutrient Accumulation On The Grazed, Long-Term Superphosphate Trial At Winchmore, New Zealand,
2024
AgResearch, NZ
An Overview Of Pasture Response, Nutrient Turnover And Nutrient Accumulation On The Grazed, Long-Term Superphosphate Trial At Winchmore, New Zealand, R J. Haynes, P H. Williams
IGC Proceedings (1977-2023)
The results of a long-term grazed, border dyke-irrigated trial studying the effects of annual maintenance rates of superphosphate (0, 188 and 376 kg/ha) for 40 years are outlined and discussed. Superphosphate applications increased pasture dry matter yields and this was attributed to a response to both added P and S. There was a build-up of soil organic matter over the duration of the experiment which was greater for the superphosphate treatments than control. Grazing sheep caused a redistribution of nutrients across experimental plots due to their behaviour of camping on the raised level areas of the plots. A balance sheet …
Phosphorus Deficiency Affects The Growth And Development Of Temperate Pasture Species,
2024
Massey University
Phosphorus Deficiency Affects The Growth And Development Of Temperate Pasture Species, P D. Kemp
IGC Proceedings (1977-2023)
Morphological and ontogenetic responses of temperate pasture species 10 P deficiency with the potential 10 affect the plant's persistence and productivity were examined. Plants were grown in pols in glasshouses. Two grass species, Lolium multiflorum and Phlalaris aquatica, were compared and 2 cullivars of Trifolium repens, Grasslands Huia and Grasslands Tahora, were compared under P-deficient and P-sufficient conditions. ShooVrool ratio and the number of tillers per plant were unaffected by P deficiency in P. aquatica but decreased in L. multiflorum. Reproductive development ceased at the double ridge stage in P-deficienl P. aq11alica. Huia was more sensitive than …
An Overview Of The New Zealand Experience In Establishing, Maintaining, And Utilizing White Clover Based Pastures,
2024
AgResearch, NZ
An Overview Of The New Zealand Experience In Establishing, Maintaining, And Utilizing White Clover Based Pastures, M B. O'Connor, A M. Bryant, R A. Prestidge
IGC Proceedings (1977-2023)
Establishment of white clover (Trifolium repens L.) involves the provision of all major and minor elements necessary for clover growth and N fixation (particularly P, S, K, Mo). Nitrogen fertiliser is not necessary. Inoculation of seed with rhizobium is required where white clover has not been grown previously and in difficult environments. Pest control where necessary is enhanced by insecticidal and nematicidal seed coatings on the white clover seed, Barty management is critical and involves regulnr close grazing during the first 6 months. Maintenance of white clover pastures involves annual inputs of fertiliser (P, S, K) with lime at …
Evaluation Of North Carolina Reactive Phosphate Rock As A Phosphorus Fertilizer For Permanent Pastures,
2024
AgResearch, NZ
Evaluation Of North Carolina Reactive Phosphate Rock As A Phosphorus Fertilizer For Permanent Pastures, A G. Sinclair, P D. Johnstone, L C. Smith, P W. Shannon, M B. O'Connor, L Nguyen, W H. Risk
IGC Proceedings (1977-2023)
North Carolina phosphate rock (NCPR) was compared with triple superphosphate (TSP) as a phosphorus (P) fertiliser for permanent grass-clover pastures over a period of 6 years at 12 sites located throughout New Zealand. Pasture production was measured by mowing, and herbage P concentrations were measured on all harvests at 2 sites. In year 1, averaged over all sites, 1 unit of P in NCPR produced the same DM response as 0.24 units of Pin TSP (substitution value=0.24). In year 6 the mean substitution value was 0.80, and over the 6-year period it was 0.60. The site with highest pH (6.3) …
Defining Economically Optimal Phosphorus Fertilizer Rates For Permanent Grass-Clover Pastures In Spain And New Zealand,
2024
AgResearch, NZ
Defining Economically Optimal Phosphorus Fertilizer Rates For Permanent Grass-Clover Pastures In Spain And New Zealand, A G. Sinclair, M Rodriguez Julia
IGC Proceedings (1977-2023)
Economically optimal annual fertiliser phosphorus Prates for maintaining permanent pastures are calculated from a long-term maintenance response curve along with fertiliser price and pasture value. Parameters of the response curve are derived from nutrient balance considerations. The system provides a logical basis for maintenance P fertiliser policies, and results are in accord with limited experimental data.
