ABSTRACT. The presence and growth of vegetation in ex-mining revegetation areas must be evaluated periodically to achieve the real revegetation objectives. The aim of this study was to analyze the diameter increment of woody plants, especially those that are intentionally planted in revegetation areas. The four sample locations were in the PT Adaro Indonesia’s revegetation areas of 2014, 2015, 2016 and 2017. In each location 10 (20 m x 20 m) plots were continuously laid out and in each plot there were 4 (10 m x 10 m) plots. The (20 m x 20 m) plots were used to record woody plant species and measure the circumference of the stem (at breast height) which was ≥62.8 cm. One of the 4 (10 m x 10 m) plots was used to record woody plants and measure the circumference of the stem which was 31.4 ? <62.8 cm. Data were tabulated and analyzed to obtain mean annual increment and current annual increment. From the two measurement periods (2018 and 2019), four woody plant species were found and met the requirements for calculating diameter increments. Balik angin (Mallotus paniculatus) has not been used for drawing conclusions because there is only 1 individual in all locations. The diameter increments of mangium (Acacia mangium) and turi (Sesbania grandiflora) tended to decrease to an undetermined age, while sengon (Paraserinthes falcataria) increased. The trend direction for current annual increment is not yet known because it is a single value. The values for mangium and turi are smaller than the diameter increments, while for sengon are higher.

Keywords: coal mining, diameter increment, revegetation, woody plants

ABSTRAK. Kehadiran serta pertumbuhan tumbuhan di area revegetasi bekas penambangan harus dievaluasi secara berkala untuk mewujudkan tujuan revegetasi. Tujuan penelitian ini adalah menganalisis riap diameter tumbuhan berkayu, terutama yang memang sengaja ditanam di area revegetasi. Empat lokasi sampel yang ditetapkan adalah area revegetasi bekas tambang batubara PT Adaro Indonesia tahun 2014, 2015, 2016, dan 2017. Di setiap lokasi dibuat 10 plot (20 m x 20 m) yang diletakkan berkesinambungan dan di setiap plot itu terdapat 4 plot (10 m x 10 m). Plot (20 m x 20 m) digunakan untuk mendata spesies tumbuhan berkayu dan mengukur keliling batangnya (setinggi dada) yang berukuran ≥62,8 cm. Salah satu dari  4 plot (10 m x 10 m) digunakan untuk mendata spesies tumbuhan berkayu dan mengukur keliling batang yang berukuran 31,4 ? <62,8 cm. Data ditabulasi dan dianalisis untuk mendapat riap diameter (mean annual increment) dan riap diameter tahunan berjalan (current annual increment). Dari dua periode pengukuran (tahun 2018 dan 2019), empat spesies tumbuhan berkayu ditemukan dan memenuhi syarat penghitungan riap diameter. Balik angin (Mallotus paniculatus) belum digunakan untuk pengambilan simpulan karena hanya ada 1 individu di semua lokasi. Riap diameter mangium (Acacia mangium) dan turi (Sesbania grandiflora) cenderung menurun sampai umur yang belum bisa ditentukan, sedangkan sengon (Paraserinthes falcataria) menaik. Arah kecenderungan riap diameter tahunan berjalan belum diketahui karena berupa nilai tunggal. Besaran nilai pada mangium dan turi lebih kecil daripada nilai riap diameternya, sedangkan untuk sengon lebih besar.

Kata kunci: penambangan batubara, revegetasi, riap diameter, tumbuhan berkayu