Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Fellowship report.

Abstract

This study aims to determine the growth of ten selected local tree species in amended sand tin tailings, and to identify cultivation practices which support the best growth of local tree species and encourage natural colonization. The 2 ha tin-mined study site is located at Riding Panjing village, Indonesia. The experiment consisted of a factorial randomized complete block design with two factors and three replicates with a total of 3345 seedlings planted at 3 densities (10 000, 2500 and 625 seedlings/ha) in 45 plots of 12×12 m. The five soil treatments were: (1) control, (2) 500 g powdered slime tailing under Lepironia articulata, (3) equal composition (1:1) 30 kg/ha of legume cover crops (LCC) Calopogonium tnucunoides and Centrosema pubescens, (4) LCCand 2.5% humic acid, and (5) LCC and top soil. The ten species were: Calophyllum inophyllum (Clusiaceae), Hibiscus tiliaceus (Malvaceae), Macaranga spp. (Euphorbiaceae), Mallotus paniculatus (Euphorbiaceae), Schima wallichii (Theaceae), Vitex pinnata (Verbenaceae), Ficus superba (Moraceae), Syzygium grande (Myrtaceae), Aporosa spp. (Euphorbiaceae), and Syzygium polyanthum (Myrtaceae). Pieces of coconut shell were placed around the root collar of each plant at planting to improve the microclimate. Results showed that the coconut shells significantly reduced soil temperatures near the seedlings in the late dry season (by 4.3 °C) and in the wet season (by 2.1 °C) in all plots. There was a significant interaction between planting density and soil treatment on survival rate, plant cover, and litter production. The highest planting density (10 000 seedlings per ha) plus treatment with LCC Calopogonvum mucunoides at 30 kg/ha gave the highest survival rate (73-79%), highest average canopy cover and highest litter production (460 kg/ha/year). H. tiliaceus, F. superba, C. inophyttum, and S. grande are the most promising of the ten native tree species for revegetating tin-mined lands. Treating plots with legume cover crops and/or top soil showed highly significant effects on recolonization. This study shows that planting appropriate native species and treating with topsoil or legume cover can accelerate succession significantly compared to natural regeneration. Although a planting density of 10 000 seedlings/ha showed the best performance, lower densities would also show marked improvements over natural regeneration at lower costs.