Sobrevivência e crescimento de espécies nativas na restauração de campinaranas degradadas por mineração de areia

Abstract

Sand mining in areas of Campinaranas causes intense negative impacts on these ecosystems, with vegetation suppression, loss of biodiversity, oxidation of organic matter and changes in water infiltration into the soil, for example. The restoration of these degraded areas constitutes one of the greatest challenges for science, considering the extreme poverty of the soils, their sandy texture and the lack of information on the cultivation of native species in these environments, from obtaining seeds, overcoming dormancy, production of seedlings and establishment and initial growth of seedling plants. This project aimed to evaluate the survival rate, initial growth of seedlings in the field under different fertilizations and physiological characteristics of the cultivated species. The study was conducted in the municipality of Manaus-AM, in an old sand extraction mine, in an environment dominated by sandy soils (Spodosols and Quartzarene Neosols). The preparation of the area included leveling activities, digging holes measuring 40 cm x 40 cm, at a spacing of 1.5 m x 1.0 m. The region's climate is humid tropical, type Af, according to the Köppen classification, characterized by an average annual temperature of 26.7º C with little seasonal variation between 25.9º and 27.7 ºC, average annual precipitation of 2,420 mm (ALVARES et al., 2013). The study was conducted between February and December 2023, including the rainy season and the dry season, in the region. Seedlings of 11 native species of Campinaranas plus Inga edulis were cultivated, subjected to different treatments with chemical fertilization, organic fertilizer and top soil. The test was conducted in a randomized block experimental design, with three replications, covering a total area of 608 m2. The species presented different survival rates, with the highest mortality coinciding with the period of lower rainfall, higher evaporation rate and higher average values of maximum temperatures. Ingá cipó (Inga edulis), Umiri (Humiria balsamifera), Clusia (Clusia nemorosa), Palm tree (Attalea microcarpa) and Pineapple (Ananas ananassoides) showed a higher survival rate. While, Miconia papillosa, white pitch (Protium heptaphyllum) ingazinha (Inga lateriflora) and pradosia (Pradosia schomburkiana) and P. palidum, presented the lowest survival rates. Ingá cipó (Inga edulis), Umiri (Humiria balsamifera) and Clusia (Clusia nemorosa) showed the greatest growth in height and neck diameter, as well as the best in the physiological characteristics evaluated, indicating high potential for the restoration of degraded sandy environments. In general, the best plant responses were observed in the treatment using limestone and chemical fertilizers, without the addition of other compounds.