The influence of fast-growing species composition on natural regeneration of coal mine reclamation

Abstract

Natural regeneration on mine reclamation can be an indicator of reclamation success. Enterolobium cyclocarpum, Samanea saman, Senna siamea, and Paraserianthes falcataria are mostly planted fast-growing species at the beginning of reclamation. Those species bind and enrich nitrogen to improve the natural regeneration of ex-mined land. This research aims to determine fast-growing species and the growth rate of natural regeneration development in the ex-mined site. The research was conducted in mine reclamation areas with different ages: 1 (125.14 ha), 4 (323.76 ha), 6 (199.44 ha), 9 (285.18 ha), and 11-year-old plantation (75.39 ha). The statistical analysis of Multivariate Analysis showed that biological species were mostly grouped with P. falcataria than E. cyclocarpum and S. siamea in the 11-year-old plantation area as well as in the 9-year-old plantation area. Most natural species were grouped with C. cyclocarpum rather than S. saman and S. siamea in a 6-year-old plantation area. In contrast, the biological species had no groups with E. cyclocarpum and S. siamea as fast-growing species in the 1-year-old plantation area. Generally, the most dominant planted fast-growing species were E. cyclocarpum (with the mean total number ± standard deviation, (35 ± 17.1)) and P. falcataria (28 ± 8.3). The number of natural regeneration species and individuals in areas dominated by P. falcataria (5 ± 1.7 and 25 ± 10.5) was greater than in areas with predominance of E. cyclocarpum (4 ± 2.6 and 11 ± 4.8). Thus, species selection is necessary to increase natural regeneration. However, further research is required to measure the tolerability of fast-growing species on other natural regeneration species.