<?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><authors><author><style face="normal" font="default" size="100%">Puerto, A</style></author><author><style face="normal" font="default" size="100%">Rico, M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">TREE CANOPY EFFECTS ON COMMUNITY STRUCTURE IN SLOPES OF MEDITERRANEAN RANGELANDS</style></title><secondary-title><style face="normal" font="default" size="100%">EKOLOGIA-BRATISLAVA</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1994</style></year></dates><publisher><style face="normal" font="default" size="100%">SLOVAK ACADEMIC PRESS LTD</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 57, NAM SLOBODY 6, 810 05 BRATISLAVA, SLOVAKIA</style></pub-location><volume><style face="normal" font="default" size="100%">13</style></volume><pages><style face="normal" font="default" size="100%">161-171</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the dehesa systems there are considerable differences in community&lt;br/&gt;structure between grassland situated under trees and in the open spaces&lt;br/&gt;between them. This difference is superimposed by another one based on a&lt;br/&gt;trophic gradient in the form of sectors which develop along slopes.&lt;br/&gt;We studied these differences and our results show that:&lt;br/&gt;1. Community diversity decreased and spatial heterogeneity increased&lt;br/&gt;from the higher to the lower sectors of the slope gradient.&lt;br/&gt;2. These trends were significantly smaller under trees.&lt;br/&gt;3. In the open spaces there was a contrast in community structure; fine&lt;br/&gt;grain in high sectors and coarse grain in the lower ones.&lt;br/&gt;4. Community heterogeneity in pares of consecutive sectors of the slope&lt;br/&gt;gradient was lower under trees than in the open spaces.&lt;br/&gt;That means that trees act as a homogenizing factor on slopes,&lt;br/&gt;maintaining a basic herbaceous structure which tends to be similar in&lt;br/&gt;various sectors. Steady conditions are thus created, which influence&lt;br/&gt;both the same sector of different slopes as well as various sectors of&lt;br/&gt;each of the slopes. The alternation of one relatively uniform structure&lt;br/&gt;(under trees) with another much more variable one (open spaces) is&lt;br/&gt;considered as essential for the functioning of the system; just as it&lt;br/&gt;has developed following the traditional land-use practices in the area.</style></abstract></record></records></xml>