Komposisi Flora dan Keragaman Tumbuhan di Hutan Rawa Musiman, Rimbo Tujuh Danau Riau

Abstract

Freshwater swamp forest is the most productive ecosystem and plays an important role in the ecological system. The aimed of this study was to analyze structure, composition, plant diversity and to identify the important abiotic environment factors influencing plant diversity on seasonal Tujuh Danau Swamp Forest, Riau. This study was carried out with the quadrat plot methods. In total 200 plots were laid on 1,000 ha area. The result revealed that 97 species of 36 families were identified in the study site. Seedlings and trees contained greater numbers of individuals than saplings and poles levels. Sterculia gilva Mig. was the dominant species in all (seedling, sapling, poles, trees) level. The dominant family in all growth levels were Euphorbiaceae and Dipterocarpaceae. Tree diameters class distribution was a reverse "J" curve indicating the forest in a normal condition. Shannon-Wienner diversity index were high at the extent of 3.08-3.29. Species distribution base on Evenness index showed that the distribution of species was unequal on seasonal swamp forest community. Soil properties of silt, sand, clay and canopy cover were the important abiotic factors influencing the diversity of seedlings on the seasonal swamp forest.

Ragam Vegetasi Hutan Rawa Air Tawar di Taman Wisata Alam Jering Menduyung, Bangka Barat

“…(Tabel 1). Penelitian Lisdayanti et al, (2016), melaporkan bahwa famili Myrtaceae di hutan rawa air tawar Rimbo Tujuh Danau merupakan salah satu famili yang memiliki anggota spesies lebih banyak dibandingkan famili lainnya.…”

“…Menurut Setiadi (2005), nilai indeks keanekaragaman dapat berkisar antara 0-7, dengan kriteria: 0-2 (rendah), 2-3 (sedang), dan > 3 (tinggi). Selain itu, menurut Lisdayanti et al (2016), bahwa indeks keragaman menggambarkan tingkat kestabilan dalam suatu komunitas. Secara umum pada lokasi yang diamati bahwa komunitas hutan rawa air tawar di TWA Jering Menduyung dalam kondisi yang kurang stabil.…”

“…Indeks kemerataan untuk semua tingkat pertumbuhan (semai, pancang, tiang dan pohon) di hutan rawa air tawar memiliki nilai kurang dari satu, yaitu berkisar antara 0-0,792 (Tabel 3). Indeks kemerataan memiliki nilai antara 0-1 dimana nilai 1 menunjukkan distribusi spesies yang sama dalam suatu komunitas (Lisdayanti et al, 2016). Menurut Gunawan et al (2011), menyatakan nilai kemerataan suatu jenis ditentukan oleh distribusi setiap jenis pada masing-masing plot secara merata.…”

“…Kemudian, Purwaningsih & Yusuf (2005), menyatakan tanah memiliki pengaruh yang nyata terhadap penyediaan berbagai unsur hara. Selain itu, Lisdayanti et al (2016), mengatakan bahwa peran sifat-sifat tanah mempunyai pengaruh penting terhadap suatu komposisi komunitas tumbuhan. Nilai rata-rata faktor fisik dan kimia tanah hutan rawa air tawar di TWA Jering Menduyung (Tabel 4).…”

New Record of Eurycoma Apiculata A.W. Benn (Simaroubaceae) From Forest Reserve of Kenegerian Rumbio, Riau, Indonesia

“…The forest inventory activities have been conducted in natural forest Sumatra by many researchers, but no report that find E. apiculata species (Wardah, 2005;Heriyanto et al, 2006;Rahayu et al, 2007;Setyowati and Wardah, 2007;Kuswanda and Antoko, 2008;Puspitaningtyas and Wawaningrum, 2009;Arifiani and Mahyuni, 2012;Silalahi and Nisyawati, 2015;Ismaini et al, 2015;Lisdayanti et al, 2016;Surya and Astuti, 2017;Des et al, 2017;Susanti et al, 2018;Nasution et al, 2018;Nursanti et al, 2018;Fauzi et al, 2019), except only reported by Nooteboom (1962) and Padua et al, (1999). The question arises, is Eurycoma apiculata in Sumatra (Indonesia) still exist or extinct?…”