Kekayaan Jenis Pohon Pada Stasiun Penelitian Ketambe Kabupaten Aceh Tenggara “Hutan Terganggu dan tidak Terganggu

Abstract

Tree species richness in disturbed and undisturbed site of Ketambe Research Station Ketambe, Southeast Aceh regency, Indonesia has been studied from March to May 2018. Research sites were determined using purpossive sampling method. Tree samples were recorded within a plot measuring 400 m2 for each sites with a total of 40 plots. Ecological parameters measured in this study were: Density (D), Relative density (RD), Frequency (F), Relative frequency (RF), Dominance (Do), Relative dominance (RDo), Importance Value Index (IVI), Shannon’s diversity index (H’), Margalef’s index (R1), and Evenness (E). Estimation of biomass (B) carbon stock (CS) was conducted using allometric equation. Physico-chemical characteristics measured were: air temperature (oC), soil acidity (pH), light intensity (lx), air humidity (%), total organic N (%), and phosphate quantity (ppm) as secondary data. Our study found 79 tree species belonging to 30 families, 61 species in undisturbed site and 47 species in disturbed site. An important species with the highest Importance Value Index (IVI) was Dysoxylum sp.3 in undisturbed site and Macaranga tanarius in disturbed site. The biodiversity was more diverse in undisturbed site (H’ = 3.70; R1 = 10.93) than disturbed site on the whole study area (H’ = 3.47; R1 = 9.10). The values of evenness (E) varied between 0.66–0.68 among sites. Estimation of tree biomass and carbon stock followed the similar trend with a total of B = 971.299 Mg/ha and CS = 485.649 Mg/ha on the whole study area. The present study revealed that some vital tree species exist in forest area of Ketambe Research Station as carbon sinks along with their high biodiversities from both disturbed and undisturbed regions. The information on tree species diversity may provide a baseline information for conservation of the biodiversity in this area.

Kekayaan Jenis Pohon pada Stasiun Penelitian Ketambe Kabupaten Aceh Tenggara “Hutan tidak Terganggu dan Hutan Terganggu” telah diteliti dari Bulan Maret sampai Mei 2018. Lokasi penelitian ditentukan dengan metode purposive sampling. Sampel diambil dengan menggunakan plot berukuran 20 x 20 m. Lokasi penelitian terdiri dari dua lokasi, lokasi I (hutan tidak terganggu) dan lokasi II (hutan terganggu) dengan jumlah total plot 40 buah. Parameter yang diukur meliputi Densitas, Frekuensi, Dominansi, Indeks Nilai Penting (INP), Indeks Keanekaragaman (H’), Indeks Margalef (R1), dan Indeks Keseragaman (E), serta indeks similaritas (IS). Karbon tersimpan dianalisis dengan menggunakan persamaan allometrik. Dari penelitian ditemukan 79 jenis pohon yang tergolong ke dalam 30 famili, 61 jenis terdapat di hutan tidak terganggu dan 47 jenis di hutan terganggu. Indeks nilai penting (INP) didominasi oleh jenis Disoxylum sp.3 di hutan tidak terganggu dan di hutan terganggu didominasi oleh Macaranga tanarius. Indeks keanekaragaman (H’) jenis pohon lebih tinggi di hutan tidak terganggu dibandingkan dengan hutan terganggu jumlah nilai 3,70 dan 3,47. Nilai indeks margalef di hutan tidak terganggu 10,93 dan 9,10 di hutan terganggu, dan indeks keseragaman diperoleh nilai 0,66 di hutan tidak terganggu lebih kecil dibanding hutan terganggu yaitu sebesar 0,68. Indeks similaritas dari kedua hutan 51,85 %, dan total karbon tersimpan tertinggi di hutan tidak terganggu yaitu (278,831 ton/h), dan (206,818 ton/h) di hutan terganggu.