POTENSI KANGKUNG (Ipomoea aquatica Forsk.) DAN RUMPUT ASINAN (Paspalum vaginatum Swartz) SEBAGAI FITOREMEDIATOR TANAH TERCEMAR LUMPUR LAPINDO DAN KARAKTER STRUKTUR ANATOMI AKAR

Rukhul Fitriyah, Dr.Retno Peni Sancayaningsih, M.Sc.

2011 | Tesis | S2 Biologi

Lumpur lapindo mengandung banyak bahan polutan yang membahayakan bagi organisme, antara lain logam berat dan senyawa lain yang toksik. Penelitian ini mempelajari potensi kangkung (Ipomoea aquatica Forsk.) dan rumput asinan (Paspalum vaginatum Swartz) dalam menyerap Pb dan Cd lumpur lapindo, kandungan Pb dan Cd pada akar dan daun serta struktur anatominya. Perlakuan dengan menggunakan campuran tanah sawah dan lumpur lapindo dengan perbandingan 100% : 0%, 75% : 25%, 50% : 50% dan 25% : 75% dengan ulangan 4 kali. Parameter penelitian adalah biomassa total tanaman, tinggi tanaman dan jumlah daun, kadar Pb dan Cd pada media tanam, kadar Pb dan Cd pada akar dan daun serta struktur anatomi akar tanaman uji. Biomassa tanaman, tinggi tanaman dan jumlah daun I. aquatica. menurun dengan meningkatnya kadar lumpur lapindo sedangkan biomassa tanaman, tinggi tanaman dan jumlah daun P. vaginatum tidak tampak jelas penurunannya pada peningkatan kadar lumpur lapindo. P. vaginatum. mempunyai ketahanan yang lebih tinggi terhadap lumpur lapindo daripada I. aquatica. Kandungan Pb dan Cd tanah tercemar lumpur lapindo menurun setelah diremediasi dengan I. aquatica maupun P. vaginatum. Absorbsi Pb dan Cd lebih banyak terdapat di akar daripada di daun baik pada I. aquatica maupun P. vaginatum. Peningkatan kadar lumpur lapindo pada media tidak merubah diameter korteks akar tetapi merubah diameter stele, jumlah trakea, merusak epidermis, mempertebal dinding sel xilem, memperluas ruang antar sel korteks I. aquatica. Peningkatan kadar lumpur lapindo mengurangi diameter korteks, diameter stele, memperluas ukuran ruang antar sel korteks P. vaginatum. tetapi tidak merubah epidermis dan tebal sel xilem.

Lapindo mud contains many pollutants such heavy metals and other toxic compounds which are harmful to organisms. This research studied potency of water spinach (Ipomoea aquatica Forsk.) and salt water grass (Paspalum vaginatum Swartz) to absorb Pb and Cd from lapindo mud media, Pb and Cd contents in roots and leaves as well as its anatomical structures. Treatments were done using mixture between rice paddy soil and lapindo mud with ratio of 100%: 0%, 75%: 25%, 50%: 50% and 25%: 75% with 4 replicates. Parameters taken were total plant biomass, plant height and number of leaves, Pb and Cd contents in leaves, roots the growth medium. Plant biomass, plant height, and number of leaves of I. aquatica decreased with increasing of Lapindo mud levels, while the biomass, plant height and leaf number of P. vaginatum did not conspicuously decline. P. vaginatum had a higher resistance to Lapindo mud than I. aquatica. Pb and Cd contents in polluted growth media were lower after remediated by I. aquatica and P. vaginatum. Pb and Cd contents absorbed by plant roots were higher than in the leaves both in I. aquatica and P. vaginatum. Increased lapindo mud levels in the growth medium did not change root cortical diameter of I. aquatica but changed stele diameter, number of trachea, damage in epidermis, xylem cell wall thicken and extended the space between the cell cortical cells. Lapindo mud levels decrease the cortical diameter, stele diameter, extended the space between cortical cells of P. vaginatum but did not change the epidermis and thickness of xylem cell wall.

Kata Kunci : Fitoremediator, Ipomoea aquatica, Paspalum vaginatum, lumpur lapindo, logam berat.