THE ENVIRONMENTAL MANAGEMENT UNITS IN THE CONSERVATION OF VEGETATION TYPES IN COAHUILA STATE

Abstract

In order to know the way in wfich the 28'i units for management and conservation of wildlife lUMA, according to its initials in Sponish) contribute to the conservation of natural vegetation types of Coahuila, the gap method was used. By the Principal Component  Analysis was determined the relationship of the vegelation  types of the state in regard  to the representativeness in protected oreas (PA). The local UMAs oover 1, 546,778 ha; T2 % of them are found, mainly, in places where the four types of primary vegelation  are present, which, according to their extent, would be as follows: desert microphilous scrub, desert rosetophilous scrub,tamaulipean thorn scrub and natural grassland. lf UMA  would be considered equivalent  to PA for biodiversity conservation they would cover five vegetation types which are gaps in current protected oreas; however, two plant communities: halophilous vegelation and gypsophilous vegetation would be represented in PA below  the reach of the national  protected average of Mexico  ( 12%). Moreaver, four vegelation  types, which represent only 12,514 ha, are not represented neither in PA nor in UMA Coahuila's UMAs oover 25% of its tomaulipean thorn scrub and mesquite land extension in primary condition, which are rurrently  under-represented in state PA network..  That means, UMA  can contribute to biodiversity conservation if they are sustainably managed, proteding naturalland cover.