SUKSESI VEGETASI ALAMI DI BEKAS TAMBANG TIMBAH PULAU BANGKA (Succession of Natural Vegetation in Post Tin-Mining Bangka Island)

Abstract

ABSTRAK 

Penelitian ini mempelajari suksesi vegetasi alami berbagai umur sere di bekas tambang timah Pulau Bangka. Komunitas sere tersebut terdiri dari overburdern 2 bulan, overburden 1 tahun, subsoil 1 tahun, tailing 3 tahun, overburden < 10 tahun, tailing < 10 tahun, overburden > 20 tahun dan tailing > 20 tahun. Hasil tersebut dibandingkan dengan hutan alam yang belum ditambang. Metode yang digunakan adalah kuadrat plot yang disesuaikan dengan persebaran vegetasi di lokasi dengan ukuran 2m x 4 m, 5m x 5m dan 10m x 20 m serta ulangan berkisar 30-15 kali. Hasil penelitian menunjukkan bahwa growthform komunitas sere overburden lebih banyak dibandingan dengan tailing. Vegetasi yang dominan pada sere awal adalah rumput Ischaemum muticum dan Imperata cylindrica. Pada sere selanjutnya didominasi oleh semak Melastoma malbathricum, juga ditemukan familia Leguminosae dan Nepenthes sp sebagai indikator miskinnya hara tanah. Sedangkan seedling pohon terbesar jarang terdiri dari Macaranga sp, Malleuca leucadendron, Schima wallichii, Viotex pubescens, Anacardium occidentale, dan Alstonia schoolaris. Ternyata kehadiran vegetasi merespon pada kandungan hara, terutama bahan organik dan nitrat. Pada komunitas sere overburden < 10 tahun dan > 20 tahun, serta tailing > 20 tahun ditemukan introduce species, yaitu Acacia spp. Adanya pohon Dyera costulata (jelutung) di hutan alam sebagai indikasi hutan tersebut adalah hutan rawa gambut. Sebaliknya pada hutan alam dengan tekstur tanahnya mirip dengan tekstur tanah pada semua komunitas sere didominasi oleh pohon dan sapling Eugenia palembanica serta seedling Eugenia longiflora.

ABSTRACT

Succession of natural vegetation at various seral-stages were studied in post tin-mining Bangka Island. These seral stages were 2 months of overburden, 1 year of tailing, 1 year of subsoil, 3 years of tailing, 10 years of overburden, 10 years of tailing, 20 years of overburden, and 20 years of tailing and were compared to the natural forest. Data were collected based on various growthforms using various quadrate plots of 2mx4m, 5mx5m, and 10mx20m, which replicated of 3 to 15 plots. The results showed that the number of growthforms of sere was found more at location of overburden more than the tailing. The dominant plants at pioneer stage were Ischaemum muticum and Imperata cylindrica. The next seral stage was dominated by shrubs of Melastoma malabathricum. We also found Leguminosae and Nepenthes sp, which indicated that the location of post mining were poor in nutrients. The tree seedlings were dispersed rarely, and consisted of Macaranga sp, Malaleuca leucadendron, Schima wallichii, Vitex pubescens, Anacardium occidentale, and Alstonia schoolaris. The present of vegetation during the seral stages were as a respon to the nutrient content especially organic matter and nitrate. On location 10 years and 20 years of overburden, and also 20 years of tailing were found introduce species of Acacia spp. Trees of Dyera costulata were found on natural forest, which were indicated that forest was peat swamp forest. The natural forest were dominated by trees and saplings of Eugenia palembanica and seedlings of Eugenia longiflora, but their soil textures were similar with all locations of post mining sere.