Caracterização das nascentes da sub-bacia hidrográfica do rio Gaviãozinho, Bahia

Abstract

The objective of this work was to characterize the water springs of the sub basin hydrographic of the river Gaviãozinho-Ba, in addition to evaluating the perception of farmers in relation to environmental conservation and organic agriculture, aiming to subsidize maintenance actions of preserved areas and recovery of degraded areas. The sources were identified with the aid of GeoBahia system and of the program Google Earth, and later were located in the field using the GPS Garmin etrex 10 model. The source were classified according to the state of conservation in five categories: Pre, Per1, Per2, Deg1, Deg2. In addition, it was identified: the location of the area; Geographic coordinates; type of source; presence of protection; duration of flow; use and occupation of the soil in the area of APP and the surroundings; main disturbances. For the springs that presented water flow was measured its flow through the method of the direct measurement in extravasation tubing. In order to evaluate the environmental perception of farmers were applied semi-structured questionnaires containing 27 questions to 25 farmers. Were visited 74 points where there could be a water springs, being that 52 of them were perennial sources, 4 were temporary springs and 18 headwaters drainage. In relation to the conservation status of perennial springs, only 20% were preserved, 33% are perturbed, being 29% classified in category Per1 and 4% Per2. The percentage found in degraded water springs was 47%, where 14% were classified as Deg1 and 33% as Deg2. It was observed a predominance of the use of the soil with pasture in APPs of the degraded sources. In the sources perturbed the association between native forest and pasture was the one that presented the highest percentage (35%). It was verified the direct access of animals to 54% of APPs of perennial springs, being that only 8% of the total number of perennial springs were properly protected. The total or partial suppression of native vegetation and the access of animals the areas of APPs were the anthropic actions detected at a higher percentage. The areas of the headwaters of drainage, ephemeral and intermittent springs, although to have important role in the hydrological dynamics, had a high degree of anthropic impact. How much the environmental perception of farmers, 44% demonstrated to recognize the importance of the sources, mainly for the supply of water for human use. All interviewees considered important to keep the riparian forest of springs, there is unanimity in relation to the desire of recovered them, moreover, the majority (88%) proved to be willing to participate in recovery projects of water springs. Questioned about which measure to be adopted to better protect the sources, 36% of respondents pointed to maintain the native vegetation, 24% pointed to the reforestation, 12% cited the use of fences, 12% cited the environmental education, 8% reported receiving financial incentives, 8% cited the need for governmental actions to support and monitor the actions of recovery and 4% cited the Payment for Environmental Services. Among those interviewed the majority (76%) stated have already heard in organic agriculture. Asked about what they understand as organic agriculture, the majority showed unaware of the various attributes involved in organic production