STUDI AWAL VEGETASI RIPARIAN DI HILIR DAS WELANG JAWA TIMUR

Abstract

Indonesia memiliki kurang lebih 40.000 jenis keanekaragaman tumbuhan yang menyusun ekosistem. Ekosistem riparian dapat ditemukan pada Daerah Aliran Sungai (DAS), dari sumber air, hulu sungai sampai ke muara di hilir. Vegetasi riparian tumbuh pada habitat peralihan antara ekosistem terestrial dan akuatik berfungsi dalam menjaga kualitas air sungai dan menjadi habitat dari berbagai jenis organisme. Sungai Welang merupakan sungai di Provinsi Jawa Timur yang melalui 3 daerah administrasi yaitu Kabupaten Malang, Kabupaten Pasuruan dan Kota Pasuruan. Sungai Welang mempunyai DAS seluas 511,60 km² dengan panjang sungai 40,09 km yang mengumpulkan air permukaan dari 57 anak sungai dan 79 sumber air di sekitar  Gunung Arjuna (+ 3.200 mdpl) dan Gunung Bromo (+ 2.400 mdpl). Namun saat ini Sungai Welang mengalami permasalahan lingkungan akibat aktivitas manusia. Solusi yang dapat diberikan untuk permasalahan tersebut adalah dengan memanfaatkan vegetasi riparian sebagai fitoremediasi lingkungan. Target utama dalam Global Strategic Plant Conservation (GSPC) adalah studi keanekaragaman tumbuhan, terutama di habitat prioritas terancam. Sehingga studi awal keanekaragaman vegetasi riparian di hilir DAS Welang menjadi sangat penting karena bersaing dengan laju degradasi lingkungan yang sangat cepat. Studi awal dilakukan selama bulan April 2021, pada bagian hilir muara DAS Welang. Data yang didapatkan kemudian dianalisis secara dekriptif dan disajikan dalam bentuk tabel dan gambar. Tercatat ada 37 Jenis vegetasi riparian berhabitus pohon yang didapatkan pada survey awal di bagian hilir DAS Welang yang termasuk dalam vegetasi mangrove (13,5%), vegetasi pantai (10,8%), dan vegetasi dataran rendah (75,7%).

Indonesia has approximately 40,000 types of plant diversity that make up the ecosystem. Riparian ecosystems can be found in watersheds (DAS), from water sources, upstream to downstream estuaries. Riparian vegetation grows in transitional habitats between terrestrial and aquatic ecosystems that function in maintaining river water quality and being a habitat for various types of organisms. Welding River is a river in East Java Provincethath passes through 3 administrative areas, namely Malang Regency, Pasuruan Regency, and Pasuruan City. TheWelang River has a watershed area of 511.60 km2 with a river length of 40.09 km which collects surface water from 57 tributaries and 79 water sources around Mount Arjuna (+ 3,200 masl) and Mount Bromo (+ 2,400 masl). However, currently, the Welang River is experiencing environmental problems due to human activities. The solution that can be given to this problem is to use riparian vegetation as environmental phytoremediation. The main target of the Global Strategic Plant Conservation (GSPC) is the study of plant diversity, especially in threatened priority habitats. Thus, the initial study of riparian vegetation diversity in the downstream Welang watershed becomes very important because it competes with the very fast rate of environmental degradation. The initial study was carried out in April 2021, in the lower reaches of the Welang watershed estuary. The data obtained were then analyzed descriptively and presented in the form of tables and figures. It was recorded that there were 37 types of tree-habituated riparian vegetation found in the initial survey in the lower reaches of the Welang watershed which included mangrove vegetation (13.5%), and coastal vegetation (10.8%), and lowland vegetation (75.7%).