Komposisi dan Struktur Rerumputan di Kawasan Danau Toba Desa Togu Domu Nauli Kecamatan Dolok Pardamean Kabupaten Simalungun Sumatera Utara

The composition and structure of grasses in Toba Lake Area Togu Domu Nauli Village, Dolok Pardamean Subdistrict, Simalungun Regency, North Sumatra has been studied from March to June 2012. The study site is determined by purposive sampling method and it is divided three locations based on altitude with 20 plots of 1 x 1 m size for each area. There are 21 species of grasses that belong to two families found at three study sites. The first area was dominated by Imperata cylindrica, the second was dominated by Leersia hexandra, and the third was dominated by Imperata cylindrica with importance values are 58.408 %, 72.202 %, and 81.316 %, respectively. The diversity index (H') of grasses are 1.826, 1.432, 1.010 at area I, II, and III, respectively and equitability index (E) of grasses are 0.658, 0.597, 0.519 at area I, II, and III, respectively. The Similarity index of grasses ranges from 46.91% to 62.56%, with the highest similarity index is 62.56% that is found between area II and III

Komposisi dan Struktur Rerumputan di Kawasan Danau Toba Desa Haranggaol Kecamatan Haranggaol Horison Kabupaten Simalungun Sumatera Utara

The composition and structure of Grasses in Haranggaol Village Haranggaol Horison Subdistrict Simalungun Regency North Sumatra has been studied from April to July 2012. The objective of the study was to determine the composition and structure of grasses at different altitudes. Sampling area was defined by purposive sampling method and divided into three locations based on altitude with 20 plots of 1 x 1 m size for each area. From the study it was found 24 species of grasses that belong to two families. The first location was dominated by Microstegium ciliatum (81.095%), the second was dominated by Deyeuxia brachyathera (68.504%) and the third was dominated by Leersia hexandra (79.158%). The diversity index (H\u27) of grasses are 1.557, 1.790 and 1.414 in the location I, II and III, respectively and equitability index (E) of grasses are 0.607, 0.661, 0.726 in the location I, II and III, respectively. The similarity index ranges from 30 to 50%, with the highest similarity index is 50% that was found between location I and II

Taxonomic Study of Pandanus (Pandanaceae) in Swamp Area, Aceh Singkil

Taxonomic study on Pandanus (Pandanaceae) in swamp area, Singkil had been conducted from November 2012 until June 2013. Based on morphological characters, 5 species of Pandanus have been identified in the area as Pandanus atrocarpus, Pandanus labyrinthicus, Pandanus militaris, Pandanus odoratissimus and Pandanus tectorius. The morphology and life cycle of species were categorized into two types, and they are medium arborescent pandan (Pandanus labyrinthicus and Pandanus militaris) and large arborescent pandan (Pandanus atrocarpus, Pandanus odoratissimus and Pandanus tectorius). Anatomical characters of Pandanus such as stomata (type, size, papilla) and epidermal cells supported the morphological features