Matas ciliares da caatinga: florística, processo de germinação e sua importância na restauração de áreas degradadas

Abstract

Caatinga has suffered strong degradation due to the people growth and the need for expansion of lands for agriculture, cattle, housing and leisure. Among several environments in the caatinga, the riparian areas are target of devastation due to the proximity of the water, soil fertility and warm weather. The aim of this work was realize a floristic survey of two areas of riparian vegetation in the caatinga and to study the germination of four species that occur in that vegetation. The floristic study was carried out in the municipality of Glória (0253155/9006452 UTM), in Bahia, and Petrolândia (0559297/9005180 UTM), in Pernambuco. The germination study was realized for Albizia inundata (Mart.) Barneby & J.W. Grimes, Piptadenia moniliformis Benth., Triplaris pachau Mart. e Trischidium molle (Benth) H.E. Ireland. The seeds were collected directly from the adult plant, manipulated, processed and submitted to the control treatment, mechanical scarification, 12 hours photoperiod and light absence. 33 families and 59 species were registered. The families with higher species richness in both areas were Cactaceae (6 species), Euphorbiaceae (6species) and Convolvulaceae (5 species). The families with higher richness for the studied areas are the same for non riparian caatinga areas of sandy and rocky soils. The floristic similarity between the two areas was 74%, indicating that those areas are very similar. In relation to the germination, Albizia inundata shows the break of dormancy mechanism after the 12 hours photoperiod treatment. The seeds of Trischidium molle have their percentage of germination enhanced when submitted to the mechanical scarification. The seeds of Triplaris pachau and Piptadenia moniliformis showed similar percentage of germination with the control and scarification treatments, indicating that there is no need for the application of the treatment of dormancy break for the seedling production.