干旱区生态环境知识资源中心

The coast of the Gulf of Mexico is characterized by dry regions with high variation in climatic conditions. This area is rich in drought-tolerant or subhumid species. The species that are potentially useful for reforestation, regreening, agroforestry activities and the production of timber, fodder, fuelwood and human food have been overexploited, resulting in the gradual decrease and degradation of their populations. This study was undertaken in order to suggest ways of improving the regeneration of these species. Fifteen native and exotic multipurpose tree species of low dry shrubland planted in monoculture in four randomized blocks. Measurements of various growth parameters, volume of trees, fodder potential and agroforestry uses over 15 years were evaluated. Eucalyptus camaldulensis Dehnh., E. microtheca F. Muell., Leucaena leucocephala (Lam.) de Wit. (exotic species), Acacia farnesiana (L.) Wild and Parkinsonia aculeata L. (native species) tend to have better characteristics in terms of growing annual rate, economic value and management schemes, while Prosopis glandulosa Torr. and Helietta parvifolia (Gray) Benth. (native species) did not establish well due to biotics problems which arose under plantation conditions. Acacia rigidula Benth., A. wrightii Benth. and two Pithecellobium spp. (native species) had intermediate yields of great interest since their multipurpose potential is the best of all 15 species. The forage potential of the exotic species (483-1684 kg DM//ha/year) were notably superior to native species (76-721 kg DM/ha/year). The firewood production volume varied between averages of 0.3-1.2 (native species) and 0.4-2.5 m(3)/ha/year (exotic species).