Yellow-brown Soil Research Articles

Uptake of native and applied selenium by pasture species

Uptake by mixed pasture of selenium applied as the element at 1, 4, and 160z per acre to a yellow-brown loam was compared with that from selenium applied at 1 oz per acre as sodium selenite. Marked increases in Se content from additions as the element, proportional to the amount applied, were found initially. These are attributed to surface contamination of the leaves. The effect persisted into the second cut in the 16 oz Se treatment. In this cut the sodium selenite had Ithe greatest effect. After 11 months little increase above controls was apparent in any treatment. In a second trial on a yellow-brown pumice soil, a comparison was made between treatments with 4 oz selenium per acre, in the forms of sodium selenite, ferric selenite, barium selenite, elemental selenium, and selenite incorporated in a “frit.” Again the trial was on a mixed pasture, but the clover constituent (mainly Trifolium repens L.) was dissected for Se determination. Uptake was greatest, and equal, from the three selenium sa...

ESTABLISHMENT OF OVERSOWN WHITE CLOVER ON UNIMPROVED NORTH AUCKLAND CLAY HILL COUNTRY

IN NORTH AUCKLAND, as is the case in all other areas of New Zealand, the key to pasture improvement lies in the introduction of legumes. Almost invariably poor pasture production is associated with poor clover growth. Contributing factors to poor clover establishment and growth are low amounts of available phosphate, potassium, molybdenum and sulphur, acid soil conditions and ineffective nodulation. This paper is concerned with the germination and establishment of white clover on unimproved North Auckland clay hill country. White clover establishment has been investigated on the soils of two northern yellow-brown earth soil suites, namely, the Marua suite from greywacke parent material and the Waiotira suite, from massive sandstone. These soils have been described by Taylor and Sutherland (1953) and are shown in their order of leaching in Tables 1 and 5, respectively.

Leaching losses of sulphate from superphosphate and gypsum applied on a soil from rhyolitic pumice

Abstract In studies on Waipahihi sand, a yellow-brown pumice soil of the Taupo suite, 97% or more of sulphate applied as superphosphate or gypsum was leached out under an alternate leaching and drying procedure. Losses were proportional to the amounts applied. They were unaffected by particle size of gypsum over the ranges 16–30, 30–60, and 60–120 mesh (B.S.S.), except in the first leaching.

Studies on the retention of sulphur by yellow-brown pumice soils

Abstract Forty yellow-brown pumice soils were examined for sulphur retention, using a laboratory leaching and incubation technique. Leaching losses of sulphate from added superphosphate ranged from 33% to 100% of that applied. Comparative sulphur losses from four out of five yellow-brown loams examined were much smaller (2-6% of the amount applied). On these volcanic ash soils, the concentration of allophane A appears to be an important factor in sulphate retention.

On the Tea Soils in Kyushu Region (Part 1)

The morphological characteristics of repre-sentative profiles and general characteristics of the tea soils in Kyushu Region were investigated.From the soil survey, the characteristics of these tea soils were generally summarized as follows :1. The tea soils of Kuroki and Ureshino derived from diluvial and tertiary soils were red-brown or yellow-brown mineral soils, and their general characteristics were mainly governed by the contents of clay in soils.2. The tea soils of Izunii derived from diluvial soils were humic soils and their general characteristics were characterized by higher contents of humus in soils.3. The tea soils of Kumamoto, Makurazaki, Chiran, Miyakonozo and Kawaminami were humic allophane soils having the origin of volcanic ash.There were many types in mode of deposition of volucanic ash, that of Kumamoto soil was belonged to aeolian type and those of others were buried type. The general characteristics of these soils were characterized by much contents of humus and allophane in soils and in the tea soils of Kumamoto and Kawaminami the general characteristics due to contents of humus and allophane appeared distinct than those of other tea soils.4. The tea soils of Takachiho was brown mineral soils, but from the analytical results of these soils, it was seemed that the tea soils of this district were relatively influenced by volucanic ash soils.

Rate of clay formation and mineral alteration in a 4000-year-old volcanic ash soil on Saint Vincent, B.W.I

The surface of a large fan of pyroclastic deposits erupted about 4,000 years ago has weathered to a clayey soil generally 6 ft. thick. The weathered deposits were originally andesitic ash consisting largely of glass and the minerals anorthite, labradorite, hypersthene, augite, and olivine. Fine vitric ash has altered to halloysite.4H ~2~ O, allophane, and hydrated ferric oxide. The vitric lapilli have decomposed to halloysite.4H ~2~ O. Anorthite crystals are etched in the soil and frosted in the underlying ash. Many hypersthene and fewer augite and olivine crystals in the soil are etched. Labradorite, hornblende, and magnetite are unaltered. The 4,000-year-old soil represents an early stage in the formation of the Yellow Earth soils of St. Vincent, which may themselves be classified with the yellow-brown volcanic-ash soils of Japan. Halloysite.4H ~2~ O has been redeposited in some late Pleistocene ash beds on St. Vincent to form dark brown, waxlike braunlehm. Whether or not the yellow-brown volcanic ash soils of St. Vincent represent an early state in the formation of a lateritic red soil cannot be demonstrated. Clayey soil formed from ash at an average rate of 1 1/2 - 2 ft./1,000 years on St. Vincent, and glass decomposed at a rate of about 15 gm./cm. ^2^ /1,000 years. The slight degree to which the unstable minerals anorthite, olivine, and the pyroxenes are altered contrasts sharply with the decomposition of the glass. Survey of the literature suggests that mineral grains have altered more rapidly in some podsols of the temperate regions than in the volcanic ash soils of St. Vincent. This contrast in weathering rate may perhaps be explained by the low pH of podsols and chemical effect of the rapidly decomposing glass of the ash soils.

A mineralogical study of soil formation in four rhyolite-derived soils from New Zealand

Summary In four yellow-brown earth and podzolised yellow-brown earth soils derived from rhyolite, much evidence concerning mineralogical changes attendant upon weathering and podzolisation has been obtained, and an explanation of the formation of the soils has been offered. Minerals varied in their powers of resistance to weathering in the order: oligoclase sanidine < mica (muscovitic) = chlorite < expanding micas (vermiculite and montmorillonite) < kaolin < gibbsite. Rhyolitic volcanic glass was less stable than sanidine, and quartz was at least as stable as gibbsite. There was some evidence to suggest that the order of resistance to podzolisation was almost the reverse of the order above, but again quartz was very resistant. Secondary silica crystallised as cristobalite appeared to be the only mineral formed by podzolisation. The sand fractions contained mainly primary minerals and indicated the relative stabilities of these minerals. The coarse and medium silts contained little other than quartz, but t...

Soil studies using sweet vernal to assess element availability IV. Phosphorus

Summary The phosphorus status of New Zealand topsoils is surveyed in terms of total, organic, and inorganic phosphorus fractions, solubility of the inorganic phosphorus in N H2SO4 and phosphorus content of the grass, sweet vernal (Anthoxanthum odoratum). Use is made of the genetic soil classification to show how the plant and soil phosphorus values are influenced by the nature and degree of the soil-forming processes. The total phosphorus contents of mineral topsoils at early stages of weathering reflect the nature of the parent rock in that red-brown loams from basalt and yellow-brown loams from andesite contain larger amounts of phosphorus than soils from more acidic rocks such as yellow-brown pumice soils and the zonal soils. Soil development sequences, representing increasing degrees of weathering and leaching, from groups of parent rocks, show a decrease in the phosphorus content of the topsoils. The greater the iron and aluminium content of the parent rock, the greater is the proportion of the origi...

The distribution of molybdenum in the soils of New Zealand

Summary Soils of the North Island have been examined for their molybdenum content. Wide variations in levels of molybdenum extracted by acid ammonium oxalate have been found for individual soil sets, but some important differences are noticeable between genetic soil groups. Total molybdenum levels in certain North Auckland soil suites are shown to decrease as the soils become more leached. In a comparison of sedimentary rocks, mudstones give soils higher in acid-oxalate-soluble molybdenum than do sandstones or greywackes. In the volcanic and igneous groups, yellow-brown loams from andesitic and rhyolitic ash are generally much higher than yellow-brown pumice soils from rhyolitic ash. Immature basalt soils have high levels of available molybdenum. Some correlations have been shown with the type of clay minerals in the soils. Response of P1lSture to molybdate topdressing has been discussed in relation to the different soil groups. A comparison of soil test levels and pasture responses has shown that acid am...