Dinamika Lengas Tanah di Bawah Tegakan Jati Muda Pada Berbagai Variasi Solum di Petak 17 Hutan Pendidikan Wanagama I, Gunungkidul, Yogyakarta

CARGONO, Prasetyo Nugroho, S.Hut,. M.Sc.

2015 | Tugas Akhir | D3 PENGELOLAAN HUTAN SV

Kenampakan pertumbuhan tegakan jati Petak 17 Hutan Pendidikan Wanagama I sangat berbeda-beda walaupun ditanam pada satu areal yang sama. Hasil identifikasi menunjukkan bahwa pada areal tersebut memiliki kedalaman solum yang berbeda-beda. Pada masing-masing kedalaman solum mengalami kenampakkan perbedaan pertumbuhan yang cukup signifikan. Salah satu faktor yang dapat menyebabkan perbedaan pertumbuhan tersebut adalah ketersediaan air dalam tanah. Perbedaan kedalaman solum berdampak pada ketersediaan air di dalam tanah mempunyai pengaruh terhadap penggunaan supply bahan makanan yang dapat diserap oleh akar tanaman untuk proses pertumbuhan. Pada solum dalam permbuhan tanaman terlihat jauh lebih baik apabila dibanding dengan solum sedang ataupun dangkal. Penelitian ini bertujuan untuk mengetahui dinamika lengas tanah pada masing-masing kedalaman solum tegakan jati muda di petak 17 Hutan Pendidikan Wanagama I, Gunungkidul, Yogyakarta. Pengukuran lengas dilakukan dengan menggunakan alat sensor HOBO U30 Shuttle yang ditancapkan pada tiap-tiap kedalaman solum tanah per-10 cm. Alat tersebut langsung menunjukkan jumlah lengas yang berada didalam tanah dengan satuan persen (%). Pada kedalaman 10 cm tersebut juga dilakukan pengukuran suhu tanah dengan tujuan untuk mengetahui apakah ada pengaruh antara ketersediaan lengas tanah dengan suhu tanah. Pengukuran dilakukan pada waktu yang relatif sama. Hasil penelitian menunjukkan bahwa Lapisan atas (kedalaman solum 10 cm) memiliki kandungan lengas tanah paling rendah pada ketiga blok solum tersebut dan semakin ke bawah ada kecenderungan semakin tinggi pada kedalaman 20 cm dan 30 cm. Dinamika (naik dan turun) terjadi pada kedalaman 40-70 cm (pada blok solum sedang dan dalam). Pada kedalaman 80-110 cm rata-ratakandungan lengasnya 12,33% antara 9,7%-17,07% (solum dalam) terjadi fluktuasi namun perbedaannya tidak terlalu terlihat seperti kedalaman 40-70 cm yaitu 11,26% antara 7,8%-14,7% (solum sedang) dan 11,66% antara 10,1%-14,5% (solum dalam).

Appearance of a stand's hardwood trees in educational forest of Wanagama 1 was completely different although they were planted in same area. The identification result showed that in that area the hardwood trees had different solum depth. In each soil depth had different appearance growth which was significant enough. One of the factors which made the different growth was the water supply on the soil. The difference of soil depth which was impacting to water supply on the soil had an influence on the usage of food supply which could be absorbed by plants' root for growth processing. On deep solum was better than middle and shallow solum on the comparison of plants' growth. This research had purpose to explore the dynamics of soil moisture under a stand of green hardwood trees on various solum (soil depth) in the compartmen number 17 in educational forest of Wanagama 1, Gunungkidul, Yogyakarta. The measuring of the soil moisture was done by using censor tool of HOBO U30 Shuttle which applicated to each solum depth in every 10 centimeters. That censor tool directly showed the result that the number of soil moisture in percent (%). In each 10 centimeters depth also measured the soil temperature which the purpose was to know if there was some influences between the supply of soil moisture and soil temperature. The measuring was done in same time. The result of the research showed that first or up line (soil depth was 10 centimerers) contained lowest soil moisture, but higher soil moisture happened in 20 and 30 centimeters soil depth in first 3 blocks. The dynamics (up and down) happened to the soil depth of 40-70 centimeters (on middle and deep solum). On the soil depth of 80-110 centimeters, the average of soil moisture contens was 12,33% which was between 9,7%-17,07% (deep solum) happened a fluctuation meanwhile the difference was not appear significantly, that was not like on the deep 40-70 centimeters which the soil moisture was 11,26% which was between 7,8%-14,7% (middle solum) and 11,56% which was between 10,1%-14,5% (deep solum).

Kata Kunci : Pertumbuhan, solum tanah, lengas tanah, growth, soil depth, soil moisture