KEMELIMPAHAN VEGETASI LANTAI DAN TANAMAN BUDIDAYA DI EKOSISTEM KARST GUNUNGKIDUL, YOGYAKARTA

DIAN PERAYANTI SINAGA, Dr. Tjut Sugandawaty Djohan, M.Sc.

2011 | Tesis | S2 Biologi

Vegetasi lantai dan tanaman lantai yang tumbuh di ekosistem karst Gunungkidul merupakan tumbuhan yang sangat tergantung pada curah hujan. Ekosistem karst Gunungkidul mempunyai lapisan tanah sangat tipis dan miskin hara. Penelitian ini dilaksanakan di ekosistem karst Desa Banaran yang mempunyai topografi datar dan Desa Saptosari yang mempunyai topografi lereng. Tujuan penelitian adalah untuk mempelajari kemelimpahan vegetasi lantai dan produktivitas tanam budidaya terhadap musim di ekosistem karst Gunung Kidul, Yogyakarta. Data vegetasi dicuplik dengan metode kuadrat plot, dengan ukur 10m x 20m, 5m x 5m dan 1m x 1m dengan ulangan 5 kali, ukuran bergantung pada densitas jenis yang hadir. Parameter yang diukur jenis vegetasi, densitas, tekstur tanah, kandungan hara dengan parameter yang diukur adalah; NO3, NH4, PO4, Ca, C-organik, K, Intensitas cahaya, suhu udara, suhu tanah, kelembapan udara, pH tanah. Di desa Banaran dan desa Saptosari ada masing- masing 2 stasiun lokasi penelitian.. Hasil penelitian menunjukkan di kedua lokasi kajian, vegetasi lantai yang melimpah adalah growthform, semak Ageratum conyzoides ,15876 dan Eupatorium odoratum 15792 individu per 0,1 ha. Dan growthform, Rumput Imperata cylindrica 358, 844, 738 individu per 0,1 ha. Sedangkan tanaman budidaya yang melimpah adalah Manihot utilissima sebanyak 200, 128, 6208 individu per 0,1 ha, dan Arachis hypogaea 15603 individu per 0,1 ha. Kemelimpahan vegetasi alami tidak bergantung pada penutupan kanopi, sebab lokasi tanpa kanopi akan menyebabkan intensitas cahaya sesuai untuk pertumbuhan semak dan rumput. Kemelimpahan tanaman budidaya bergantung pada penutupan kanopi dan topografi.

Floor vegetation and plants that grow in the ecosystem of karst in Gunungkidul depend greatly to the rainfall. The ecosystem of karst Gunungkidul has a very thin soil sphere and it is poor of hara. This study was conducted in the ecosystem of karst in the village of Banaran with the flat topography and in the village of Saptosari with the slope topography. This study aimed to learn the abundance of floor vegetation and the productivity of cultivated plants to the seasons in the ecosystem of karst in Gunung Kidul, Yogyakarta. Data of vegetation was collected by using the method of plot quadrate, using the measures of 10m x 20m, 5m x 5m, and 1m x 1m and it was repeated five times, and the measures would depend to the density of kind of presented things. The measured parameters were the kind of vegetation, density, soil texture, hara content with the measured parameters of NO3, NH4, PO4, Ca, C-organic, K, light intensity, air temperature, soil temperature, air humidity, and pH of soil. In the village of Banaran and Saptosari, there were 2 stations of study location respectively. The study results showed that in both study locations, the abundance of floor vegetations were growthform, bushes of Ageratum conyzoides, 15876 and Eupatorium odoratum 15792 individually per 0.1 ha, and growthform, grass of Imperata cylindrica 358, 844, 738 individually per 0.1 ha. Whereas the plentiful cultivated plants were Manihot utilissima, they were 200, 128, 6208 individually per 0.1 ha, and Arachis hypogaea, 15603 individually per 0.1 ha. The overabundance of natural vegetation did not depend to the canopy closing. It was because of location with any canopy, it would make the light intensity appropriate with the growth of bushes and grass. Thus, the abundance of cultivated plants greatly depend to the closing of canopy and topography.

Kata Kunci : Vegetasi karst, kesuburan tanah, kondisi kawasan karst, perubahan iklim.