<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">The influence of Pinus radiata, Quercus suber, and improved pasture on soil chemical properties</style></title><secondary-title><style face="normal" font="default" size="100%">AUSTRALIAN JOURNAL OF SOIL RESEARCH</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1999</style></year></dates><publisher><style face="normal" font="default" size="100%">CSIRO PUBLISHING</style></publisher><pub-location><style face="normal" font="default" size="100%">150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA</style></pub-location><volume><style face="normal" font="default" size="100%">37</style></volume><pages><style face="normal" font="default" size="100%">509-526</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Soil acidification and related land degradation issues are assuming&lt;br/&gt;increasing importance in Australia and challenging the concept of&lt;br/&gt;sustainability of current land management systems. In this study, the&lt;br/&gt;impacts of tree plantations of 2 species and permanent pasture on soil&lt;br/&gt;chemical properties are compared. Soil samples were collected from the&lt;br/&gt;top 50 cm (0-5, 5-10, 10-15, 15-20, 20-30, and 30-50 cm depths) from 3&lt;br/&gt;adjacent sites carrying pasture and monocultures of Pinus radiata&lt;br/&gt;(radiata pine) and Quercus suber (cork oak) on a deep-surfaced yellow&lt;br/&gt;podzolic soil, and differences in soil pH and other soil chemical&lt;br/&gt;properties were examined. In the surface 0-5 cm, pH was similar at all 3&lt;br/&gt;sites. Below that depth, soil pH was significantly lower and&lt;br/&gt;exchangeable Al greater under the cork oak stand than at the other 2&lt;br/&gt;sites. Consistent with a decrease in soil pH there was significantly&lt;br/&gt;less exchangeable Ca under cork oak. Also, less clay was observed under&lt;br/&gt;the cork oak stand and this is taken as evidence of the degradational&lt;br/&gt;impact of soil acidification.&lt;br/&gt;An estimate of Ca in the top 50 cm of the soil implies considerable loss&lt;br/&gt;of Ca under oak, probably by leaching and loss of litter down the slope.&lt;br/&gt;Evidence is presented to show that there has been more Fe and Al&lt;br/&gt;movement under oak than under pasture and pine, this being ascribed in&lt;br/&gt;part to the greater Al and Fe mobilising capacity of the water-soluble&lt;br/&gt;component extracted from freshly fallen leaf litter of oak. The Fe and&lt;br/&gt;Al composition of the oxalate extract from concretionary material at&lt;br/&gt;10-30 cm under oak is consistent with a process similar to&lt;br/&gt;podzolisation. Pseudogleying of Fe and Al may have accompanied the&lt;br/&gt;leaching of bases from the system and a reduction of pH.</style></abstract></record></records></xml>