Phosphorus nutrition of high rainfall pastures - Peel Harvey estuarine system study (phase II) and related phosphorus work

A. Sources, rates, time of application of phosphorus on high rainfall pastures. 80AL2, 80AL5, 81AL5, 81AL6, 81KE2, 81MA4, 82AL10, 82HA31, 82HA32, 83HA26, 83HA27. B. Soil test calibration curve trials on Bassendean sands. 82HA20, 82HA21, 82HA22, 82HA23, 82HA24, 82HA25, 82HA26, 82HA27, 82HA28, 82HA29, 82HA30. C. Soil test calibration curve trials on Coolup sands. 83HA20, 83HA21, 83HA22, 83HA23, 83HA24, 83HA25. D. Phosphorus rundown. 82HA14, 82HA15, 82HA16, 82HA18. NOTE: Summary is in two parts. 1. Peel Harvey catchment program (Deeley, Barker). 2. General program on high rainfall sandy soils (Yeates, Clarke). Summary of Experimental Work. General Aims. The work summarized here was commenced with the following aims: 1. To improve the efficiency of agricultural utilization of phosphorus applied to pastures on the deep leaching sands of the high rainfall areas. 2. To minimize phosphorus loss to drainage from the deep sand, and thus reduce eutrophication problems in adjacent waterways. Five potential ways of reducing the phosphorus losses from fertilizer sources while still maintaining optimum level of agricultural productivity were considered possible. These were: 1. The use of accurate soil tests for predicting phosphorus requirements and thus ensuring that only phosphorus actually required is applied. 2. Modification of times of application of soluble phosphorus fertilizer to maximise the plant utilisation.of applied P, and to minimise losses. 3. Development of phosphorus fertilizers of lower water solubility than ordinary superphosphate (and hence with reduced leaching losses). 4. Use of deep rooted and/or perennial plant species which are better able to utilize applied soluble P. 5. Modification of the sandy soils to increase phosphorus adsorption capacity and hence reduce or eliminate leaching losses. To date research has been chiefly concerned with the first three of these possibilities

Modifying fertiliser practices

If modified fertiliser practices are adopted phosphorus losses from the Peel-Harvey catchment can be reduced. Farmers can save money on fertiliser applications and the need for more expensive catchment management measures to reduce algal pollution of the estuary will be avoided. Research data available so far indicate that, with farmer co-operation and the use of the new slow release fertiliser New Coastal Superphosphate, long-term phosphorus application rates can be reduced by 30-40 per cent - and possibly even halved - without lowering agricultural production. This will also reduce phosphorus loss to drainage water. Although much of the research since 1982 has concentrated on the Peel-Harvey catchment, many of the results apply to all of the high rainfall coastal belt between Perth and Albany. Already farmers throughout this area have benefited from the researc

Rock phosphates : fertilisers for sandy soils?

Rock phosphates, from which water solubls phosphorus fertilisers such as superphosphate are manufactured, sometimes appear attractive to farmers because of their relatively low cost. But redearch has shown t6hat on most western australian soils they are not economical fertilisers. However, some deep sandy soils of the State\u27s high rainfall area are exeptions. On these soils, rock phosphates compare favourably with superphosphate for plant growth. But how can these deep sands be identified. This article describes research to define the soil characteristics necessary for rock phosphates and fertilisers containing rock phosphate, such as Coastal superphosphate, to be effective substitutes for superphosphate

Phosphorus nutrition of high rainfall pastures - Peel Harvey estuarine system study

1. Field experiments. A. Sources, rates, time of application of phosphorous on high rainfall Pastures - 80AL2, 80ALS, 81AL5, 81AL6, 81KE2, 81MA4, 82AL10, 82HA31, 82HA32, 83HA26, 83HA27. B. Soil test calibration curve trials. 82HA20, 82HA26, 82HA29, 83HA20, 83HA21, 83HA22, 83HA23, 83HA24, 83HA25. C. P sources and rates on sandy soils of the high rainfall areas - 84AL33, 84AL34, 84HA18, 84HA25. D.Maintenance P trials - 84AL32, 84HA17, 84HA24, 84HA28. 2.Glasshouse Experiments. 84GL5 - 1. Phosphorus sources on subterranean clover on sandy soils. 2. Soil test calibration experiment

Phosphorus nutrition of high rainfall pastures, Sulphur nutrition of pastures and Sulphur - low rainfall.

Phosphorus nutrition of high rainfall pastures - Peel Harvey Estuarine System Study and related phosphorus work. (1) Sources, rates, time of application of phosphorous on high rainfall pastures. 81AL5, 81AL6, 82AL10, 82HA32, 83HA26, 83HA27. (2) P sources and rates on sandy soils of the high rainfall areas. 84AL33, 84AL34, 84HA18, 84HA25. (3) Maintenance rate of P on pastures on sandy soils. 84AL32, 84HA17, 84HA24, 84 HA28. Sulphur nutrition of pastures A. Sulphur - high rainfall (2684 EX/4054EX) (1) Sources, rates, time of application of sulphur to pastures. 80AL4, 80AL4B (2) S sources and rates on pastures on sandy soils of the high rainfall areas. 84HA20, 84HA27 (3) Maintenance rate of S on pastures on sandy soils. 84AL35, 84HA19, 84HA26 B. Sulphur - low rainfall (1) Sulphur on pastures. 82AL9, 82KA4 (2) Sulphur requirements of wheat. 85TS24 81AL5, 81AL6, 82AL10, 82HA32, 83HA26, 83HA27, 84AL33, 84AL34, 84HA18, 84HA25, 84AL32, 84HA17, 84HA24, 84HA28, 80AL4, 80AL4B, 84HA20, 84HA27, 84AL35, 84HA19, 84HA26, 82AL9, 82KA4, 85TS24

Cartan subalgebras and the UCT problem, II

We show that outer approximately represenbtable actions of a finite cyclic group on UCT Kirchberg algebras satisfy a certain quasi-freeness type property if the corresponding crossed products satisfy the UCT and absorb a suitable UHF algebra tensorially. More concretely, we prove that for such an action there exists an inverse semigroup of homogeneous partial isometries that generates the ambient C*-algebra and whose idempotent semilattice generates a Cartan subalgebra. We prove a similar result for actions of finite cyclic groups with the Rokhlin property on UCT Kirchberg algebras absorbing a suitable UHF algebra. These results rely on a new construction of Cartan subalgebras in certain inductive limits of Cartan pairs. We also provide a characterisation of the UCT problem in terms of finite order automorphisms, Cartan subalgebras and inverse semigroups of partial isometries of the Cuntz algebra $\mathcal{O}_2$. This generalizes earlier work of the authors.Comment: minor revisions; final version, accepted for publication in Math. Ann.; 26 page