DAMPAK FASILITATIF TUMBUHAN LEGUM PENUTUP TANAH DAN TANAMAN BERMIKORIZA PADA SUKSESI PRIMER DI LAHAN BEKAS TAMBANG KAPUR (Facilitative Impacts of Legume Cover-crop and Mycorrhizal-inoculated Plant on Primary Succession of Limestone Quarries)

Abstract

ABSTRAK

Penambangan batu kapur dengan metode penambangan terbuka yang meliputi penghilangan vegetasi, pengeboran dan pengebomanan untuk mengeksplotiasi material batu kapur mengakibatkan kerusakan ekosistem. Pemulihan secara alami pada lahan tersebut berjalan lambat karena kondisi tapak dalam proses suksesi tidak mendukung perkembangan vegetasi alaminya. Pembentukan pertanaman diduga memfasilitasi kehadiran tanaman lain melalui perbaikan karateristik lingkungan yang rusak dan/atau peningkatan ketersediaan sumber hara. Dampak fasilitatif pembentukan pertanaman tumbuhan legum penutup tanah (Centrosema pubescens) dan tanaman bermikoriza (Vitex cofassus) dipelajari pada suksesi primer di lahan bekas tambang kapur TNS. Kehadiran tumbuhan alami diukur menggunakan kerapatan individu, keanekaragaman dan jumlah jenis melalui sampling vegetasi dengan metode plot kuadrat secara sistematis berdasarkan tingkat habitusnya. Kondisi tapak diukur berdasarkan ketebalan dan biomasa seresah, kadar bahan organik tanah dan kadar karbon organik tanah. Penelitian dilakukan pada 4 tipe areal di lahan bekas tambang kapur yaitu areal terbuka/kondisi alami tanpa pertanaman, areal pertanaman legum penutup tanah, areal pertanaman tanpa mikoriza dan areal pertanaman bermikoriza. Hasil penelitian menunjukkan pertanaman legum penutup tanah dan pertanaman bermikoriza memperbaiki kondisi tapak lahan bekas tambang kapur. Pembentukan tanaman legum penutup menghasilkan banyak seresahdengan ketebalan 1,08 cm dan biomassa 188,96 g/m²dan dekomposisi selanjutnya meningkatkan bahan organik tanah sebesar 3,80% dan kandungan karbonorganik sebesar 2,20%. Pembentukan pertanaman juga memberikan dampak yang sama, khususnya yang diinokulasi FungiMikoriza Arbuskula (FMA) menghasilkan seresah dengan ketebalan 1,32 cm dan biomassa 220,48 g/m², dengan kadar bahan organik tanah sebesar 3,66% dan karbon organik tanah sebesar 2,03%. Perbaikan kondisi tapak tersebut mempercepat kehadiran tumbuhan alami melalui peningkatkan kerapatan individu dan keanekaragaman jenis pada semua tingkatan habitus, meskipun untuk tingkat herba dan semak, kerapatan individu dan keanekaragaman jenis terendah pada areal pertanaman tanpa mikoriza.

ABSTRACT

Limestone mining using open pit mining method that involves vegetation removal and soil drilling and blasting in accessing limestone material has caused ecosystem damages. Natural recovery of such a harsh site is a slow process as the site condition in the successional process do not favor the natural vegetation development. Plants Establishment could facilitate other plants by ameliorating harsh environmental characteristics and/or increasing the availability of nutrient resources. Facilitation impact of legume cover crop (Centrosema pubescens) and mycorrhizal-inoculated plantation (Vitex cofassus) was studied on primary succession of TNS limestone mining quarry. The emergence of natural plants is measured using individual density, diversity and number of species by quadrat systematic plot method base on their habitus. Site conditions measured by litterfall thickness and biomass, soil organic matter content and soil organic carbon levels. The study was conducted in four types of areas on limestone postmining lands are open areas/natural conditions without planting, legume cover crop area, non mycorrhizal-inoculated plant area and mycorrhizal-inoculated plant area. The results indicated, establishment of legume cover crops and mycorrhizal-inoculated plants improved site conditions of limestone quarry. Legume cover crops establishment produced a large amount of litters with 1.08 cm of a thickness and 188.96 g/m² of biomass, and it’s subsequent decomposition increased soil organic matter of 3.80% and the organic carbon content of 2.20%. Plantation formation gave similar impact as well, particulary those inoculated with Arbuscula Mycorrhizae Fungi (AMF) produced amount of litters with 1.32 cm of a thickness and 220.48 g/m² of biomass, with 3.66% of soil organic matter content and 2.03% of soil organic carbon. Improvement of site conditions have accelerated the emergence of a natural plant and resulted in individual density and species diversity on all habitus type, although the least herbs and shrubs were found in area of non mycorrhizal-inoculated plantation.