ANALISIS VEGETASI SEMAK, HERBA, DAN RUMPUT DI AREA UMBUL NILA KABUPATEN KLATEN DAN MATA AIR MUDAL KABUPATEN GUNUNGKIDUL

FATIMATUZZAHRA, Dr. Retno Peni Sancayaningsih, M.Sc.

2014 | Tesis | S2 Biologi

Air merupakan komponen penting bagi proses kehidupan. Salah satu sumber air tanah yang potensial adalah mata air. Vegetasi lantai berperan sebagai lapisan pelindung atau penyangga antara atmosfer dan tanah, dan berperan terhadap infiltrasi air hujan ke dalam tanah. Tujuan penelitian ini yaitu untuk menganalisis vegetasi semak, herba, dan rumput di area mata air, mengetahui kemampuan evapotranspirasi dan peranan vegetasi semak, herba, dan rumput terhadap infiltrasi air hujan. Penelitian dilaksanakan pada musim kering antara bulan Juli 2013-Februari 2014 di area Umbul Nila, Tulung, Klaten, Jawa Tengah dan mata air Mudal, Purwosari, Gunungkidul, D.I.Yogyakarta. Metode pengambilan sampel secara acak sederhana. Kerapatan, indeks keragaman, dan indeks nilai penting (INP), dihitung untuk masing-masing growth form. Pengukuran evapotranspirasi masing-masing growth form dilakukan melalui simulasi hujan pada lahan bervegetasi dan tidak bervegetasi. Hasil analisis di area Umbul Nila, diperoleh 8 famili, 17 spesies vegetasi lantai dan 5 famili dengan 18 spesies disekitar mata air Mudal. Hasil perhitungan diperoleh 3 jenis vegetasi dengan nilai INP tertinggi dari masing-masing growth form semak, herba, dan rumput. Area Umbul Nila growth form semak berturut-turut: Salvia riparia 11,1%, Mimosa pudica 5,8%, dan Sida rhombifolia 4,5%. Growth form herba berturut-turut: Heliotropium indicum 33,5%, Bidens pilosa 32%, Centrosema pubescens 7,5%. Growth form rumput: Ischaemum triticeum 16,7%, Eleusine indica 11,6%, Imperata cylindrica 10,5%. Kemudian di sekitar mata air Mudal growth form semak berturut-turut: Chromolaena odorata 21,4%, Flemingia macrophylla 16,9%, Triumfetta rhomboidea 7,6%. Growth form herba berturut-turut: Elephantopus scaber 27,7%, Centrosema pubescens 8,3%, Tridax procumbens 4,7%. Growth form rumput: Ischaemum triticeum 28,6%, Paspalum conjugatum 26%, dan Digitaria sanguinalis 14%. Hasil pengukuran evapotranspirasi di Umbul Nila, growth form herba memiliki kemampuan transpirasi paling rendah dan growth form semak memiliki kemampuan evaporasi terendah. Mudal, growth form rumput memiliki kemampuan transpirasi paling rendah dan evaporasi terendah pada growth form herba. Hasil percobaan infiltrasi melalui simulasi hujan, diketahui infiltrasi air hujan di Umbul Nila pada lahan tertutup growth form rumput sebesar 75% lebih tinggi dibandingkan lahan tertutup semak, herba dan lahan tak bervegetasi. Mudal, infiltrasi air hujan untuk lahan tertutup semak sebesar 97% dibandingkan lahan tertutup herba, rumput, dan lahan tak bervegetasi.

Water is an important component for Life. One potential source of ground water is spring. Floor vegetation acts as a protective layer and contribute to the infiltration retention. The purpose of this study was to analyze of shrubs, herbs, and grasses vegetation around springs and study its role in the retention of water infiltration. The study was conducted in dry season between July 2013- February 2014 in Umbul Nila’s spring, Tulung, Klaten, Central Java and Mudal’s spring, Purwosari, Gunungkidul, D.I.Yogyakarta. The simple random sampling method was used. Density, index of diversity, and index of critical value (INP), calculated for each growth form. Measurement of evapotranspiration of each growth form was done through rainwater simulation on land vegetation and bare-land. The results of floor vegetation analysis in Umbul Nila’s spring, was obtained 8 families, 17 species of vegetation floors and 5 families with 18 species around Mudal’s spring. The results of calculation, for 3 species have the highest INP value each plot of growth form shrubs, herbs, and grasses. Growth form of shrubs in Umbul Nila’s area: Salvia riparia 11,1%, Mimosa pudica 5,8%, and Sida rhombifolia 4,5%. Growth form of herbs: Heliotropium indicum 33,5%, Bidens pilosa 32%, Centrosema pubescens 7,5%. Growth form of grasses: Ischaemum triticeum 16,7%, Eleusine indica 11,6%, Imperata cylindrica 10,5%. Whereas in Mudal, Growth form of shrubs: Chromolaena odorata 21,4%, Flemingia macrophylla 16,9%, Triumfetta rhomboidea 7,6%. Growth form of herbs: Elephantopus scaber 27,7%, Centrosema pubescens 8,3%, Tridax procumbens 4,7%. Growth for of grasses: Ischaemum triticeum 28,6%, Paspalum conjugatum 26%, and Digitaria sanguinalis 14%. The results show that evaporation, the lowest capable of transpiration in Umbul Nila area is growth form of herbs. The lowest capable of evaporation is growth form of shurbs. Mudal, the lowest capable of transpiration is growth form of grasess and the lowest of evaporation is growth form of herbs. The results showed that infiltration retention experiment showed that the ability of water infiltration in Umbul Nila on grass-covered land was 75% is higher than the land covered with shrubs, herbs, and bare-land. While in Mudal, shrub covered by 97% compared to the land covered herbs, grasses, and bare-land.

Kata Kunci : Analisis Vegetasi, Evapotranspirasi, Infiltrasi, Umbul Nila, Mudal