Abstract
ABSTRACT Environmental factors, especially light, temperature, and edaphic conditions are of great importance for the establishment of plant communities. In areas degraded by deforestation, these factors can vary greatly, which may affect the recolonization of the typical populations in the altered area. This study evaluated the development of seedlings of pioneer mangrove species under different levels of shading in soil substrate degraded by deforestation, aiming to assess the effect of deforestation on the recolonization of mangrove forests, which may be of help in the production of seedlings and recovery of deforested areas. The study was conducted in the municipality of Acaraú in the state of Ceará, Brazil. The species Avicennia schaueriana Stapf and Leechm. ex Moldenke (1939) and Laguncularia racemosa C. F. Gaertn (1807) were used in the study, and the substrate was collected from an area impacted by deforestation. The propagules and seedlings were exposed to full sun and 30, 50 and 70% shading. The results revealed that the treatment at full sun had the lowest germination rate of 86.66% for L. racemosa. Seedlings of both species showed a significant difference and better quality between shading treatments and full sun. The height of the seedlings showed a correlation above -0.90 with ambient temperature. L. racemosa tested in full sun had a viable seedling reduction of 50% and A. schaueriana was superior. It is concluded that the natural regeneration of a mangrove area can be compromised under the conditions of total deforestation with high sun exposure and degraded soils. Human intervention in providing 50% shading is essential for the development of seedlings and regeneration of the area impacted by deforestation.
Highlights
Mangroves are ecosystems established in coastal areas with average temperatures above 16 °C, brackish water, unconsolidated soil, and characterized by interactions between soil, freshwater and seawater (Saenger, 2002; Tomlinson, 2016; Duke, 2017)
This study evaluated the development of seedlings of pioneer mangrove species under different levels of shading in soil substrate degraded by deforestation, aiming to assess the effect of deforestation on the recolonization of mangrove forests, which may be of help in the production of seedlings and recovery of deforested areas
Mangrove forests in the state of Ceará are composed of four plant species, namely Avicennia germinans L. (Stearn 1958), A. schaueriana, Laguncularia racemosa, and Rhizophora mangle L. (1753), while another species, Conocarpus erectus L (1753), occupies higher ground and receives low tidal influence (Camargo Maia and Coutinho, 2012; Vale and Schaeffer-Novelli, 2018)
Summary
Mangroves are ecosystems established in coastal areas with average temperatures above 16 °C, brackish water, unconsolidated soil, and characterized by interactions between soil, freshwater and seawater (Saenger, 2002; Tomlinson, 2016; Duke, 2017). The canopy of mangrove forests can present a wide variety of sunflecks, depending on the plant species, arrangement of canopies, and conservation of the mangrove ecosystem (Asaeda et al, 2016). Sunflecks are small spaces in the canopy structure of a forest where the light passes through. They are essential for the germination and growth of propagules, seedlings, and juvenile plants in the soil of mangroves (Maciel et al, 2002). Intense changes in this environment, such as deforestation, will result in a great increase in light as reported by Querino et al
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
