ANALISIS KONDISI HABITAT DAN PERAKARAN TUMBUHAN BAWAH PADA DAERAH TERBUKA DAN DI BAWAH TEGAKAN CEMARA UDANG DI PESISIR LEMBUPURWO, KEBUMEN

HESTI WULAN NDARI, Dr. Dra. Winastuti Dwi Atmanto, M.P. ;Dr. Ir. Haryono Supriyo, M.Agr.Sc

2017 | Tesis | S2 Ilmu Kehutanan

Kawasan pesisir dengan struktur tanah berpasir tanpa adanya pohon memiliki suhu dan kadar garam tinggi, hembusan angin yang kencang, serta kandungan unsur hara sedikit. Keterbatasan kondisi lingkungan tersebut berpengaruh terhadap keberadaan tumbuhan bawah. Penelitian ini bertujuan mengetahui komposisi, pola sebaran, kondisi habitat dan perakaran tumbuhan bawah yang ditemukan di pesisir Lembupurwo. Penelitian dilakukan dengan menggunakan metode garis transek yang ditetapkan secara random. Pengamatan tumbuhan bawah dilakukan pada 3 tipe tapak yaitu dekat laut, di bawah, dan di belakang tegakan cemara udang. Jalur transek dibuat tegak lurus garis pantai. Titik awal pembuatan jalur dimulai 53 m dari garis pantai dengan jarak antar jalur 95 m. Tiap jalur dibagi menjadi segmen-segmen berupa petak ukur berukuran 2x2 m2 yang diletakkan secara diagonal antar petak untuk pengamatan tumbuhan bawah. Total petak ukur yang diamati 81 plot, dari luasan kawasan 72960 m2. Jenis tumbuhan bawah diidentifikasi, panjang dan jumlah akar diukur, kondisi lingkungan dan kualitas tanah yang meliputi pH, DHL, kandungan N total, P dan K tersedia diamati. Kawasan pesisir lembupurwo terdapat 20 jenis dari 13 famili tumbuhan bawah dengan 3 jenis pola sebaran acak dan 17 jenis pola sebaran mengelompok. Spinifex littoralis memiliki perakaran paling panjang demikian juga jumlah akar terbanyak, terutama pada areal yang terbuka. Nilai pH dan daya hantar listrik di bawah tegakan 6,41; 32,23us/cm, lebih rendah jika dibandingkan dengan lokasi dekat laut. Kandungan N-total dan P-tersedia di bawah tegakan cemara berurutan 0,03 %; 5,05 ppm lebih tinggi dari kedua lokasi yang lain.

Coastal areas with sandy soil structure without trees have high temperature and salinity, strong wind, as well as minimum nutrient content. The limitation of the environment conditions affects the variety of understorey. This research aims to figure out the composition, distribution patterns, habitat conditions and rooting from understorey species which are found in coastal sandy areas at Lemburpurwo. The research was conducted using line transect method defined by systematic sampling with random start. The observations of understorey were carried out on 3 types of treads near from the sea, under and behind cemara udang stands. Paths are made perpendicular within approximately 53 m from the shoreline and the distance between lines is 95 m. Each track was divided into segments in the form of 2x2 m2 plots which were laid out diagonally between plots for understorey observation. 81 plots were taken, where the size of the area is 72960 m2. Understorey plant species were identified, the length and number of roots were measured, environmental conditions and soil quality including pH, DHL, N total content, P and K available were observed. Lembupurwo coastal sandy area consists of 20 species of 13 plant families with 3 types of random distribution pattern and 17 types of clustered distribution pattern. Spinifex littoralis has the longest root as well as the largest number of roots, especially in open areas. The pH values and electrical conductivity below the stands of 6.41; 32,23us/cm are lower when compared to locations near the sea. Ntotal and P available under stands are available 0,03%; 5,05 ppm which is higher than the other two locations.

Kata Kunci : Kawasan Pesisir, Tumbuhan Bawah, Habitat, Perakaran;Coastal Sandy Area, Understorey, Habitat, Root