Judul: Keanekaragaman lumut sejati di Taman Nasional Gunung Merapi Sleman, Yogyakarta
Abstrak: Mosses are a group of non-vascular plants. It accurs abundantly in tropical rain forest. Substrate type and the availability of substrate are important in affecting the diversity of mosses. Eruption of Merapi volcano Oktober 2010 have a great demages on the vegetation of Mount Merapi National Park. Many trees are burned and uprooted. The understory were covered by volcanic material. Mosses might have important roles in the secondary succession followed the vulcano eruption.This research aimed to record and describe the diversity of the mosses species in the secondary succession at the vegetation of the national park and to make identification key of the mosses. Samples were collected in three sites area sixteen month after the eruption in 2010, namely Pronojiwo, Gandok, and Kinahrejo. Purposive sampling method was used to record the diversity of mosses. In addition, quadratic sampling method was used to determine the dominant mosses in the successional process. Identified mosses were listed into a list. Total of 41 species of acrocarp and 4 species of pleurocarp mosses were found in the sites. Mosses diversity in Kinahrejo are quite similar to Gandok but it was different with Pronojiwo. Most mosses were found on terrestrial substrate, that are soil, sand, and rock. Trematodon conformis is a dominant pioneer mosses in the successional process of the national park.
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Judul: Keanekaragaman Tumbuhan Bawah Pasca Erupsi Merapi di Taman Nasional Gunung Merapi, Yogyakarta
Abstrak: The eruption of Merapi Volcano in 2010 caused a great damage to the surrounding ecosystem. The recovery of surrounding ecosystem was done through succesional process. Organisms occur during early succesional stage are understory plants, thus they could be used as indicator of early stage succesion of damaged vegetation in Mount Merapi. The objective of this research was to describe and compare the diversity of understory plants after the eruption of Merapi Volcano in 2010 in Mount Merapi National Park, Sleman Region, Yogyakarta in two locations namely Gandok and Kaliurang Recreational Park. Gandok was categorized as high damaged location, while Kaliurang Recreational Park represented low damaged location. Vegetation was analyzed using quadratic method. Plants sample was identified in laboratory. Vegetation analysis generated the value of Significant Value Index (SVI), Diversity Index (H’), and Similarity Index (IS). Results showed that understory plant diversity of Gandok consist of 74 species and 63 genera, while Kaliurang Recreational Park consist of 49 species and 44 genera. The highest SVI was obtained by Digitaria nuda in Gandok and Brachiaria reptans in Kaliurang Recrational Park. Gandok and Kaliurang Recreational Park have a low similarity of understory community. Both location were categorized in medium diversity level.
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Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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