Judul: Kelimpahan Anggang-anggang (Ptilomera dromas Breddin) di Sungai Ciliwung yang Berpotensi sebagai Bioindikator Kualitas Air.
Abstrak: People and home industries activities along Ciliwung river impact to water quality. Pollutant in body of river will impact to water quality and organisms, included water strider. Water striders (Gerridae: Hemiptera) are semiaquatic insect. Gerrids, Ptilomera Amyot and Serville is easy to know, because have rather big body and have sexual dimorfism. A bigger body male than female is unusual in gerrids. Some species of water striders were used as water bioindicator. Gerris spinolae is effective bioindicators for monitoring pollution in some tropical ponds under anthropogenic stress, whereas G. argentatus, G. odontogaster, G. lateralis, dan G. thoracicus used as bioindicator of heavy metals. The purpose of this research was to study the abundance of P. dromas in Ciliwung river related to water quality. Five stations in upper Ciliwung river were used i.e, Cilember, Cijulang, Gadog, Katulampa, and Sempur stations. Abundance of water striders were observed by census method. Water striders were count directly along the edge of the river on each station. Observations were conducted four times each day, at 07.00-11.00 am. Abundance of water striders each stations was observed five times in November, December 2013, April, and May 2014. Measurement of environmental parameters was conducted at each station with five replicates, i.e. water temperature, air temperature, pH, and water flow. Water sampling was conducted by using a sampel bottle 1 L, then put in an ice box 4oC. Water samples were analyzed in the Laboratory PROLING Faculty of Fisheries and Marine Science Bogor Agricultural University, consist of biological oxygen demand (BOD), dissolved oxygen (DO), CO2 free, total Nitrogen (N), hardness, and total suspended solid (TSS). A normal data of environmental parameters were analyzed by One-Way ANOVA followed by Tukey test. Abundance of adult, nymph and total P. dromas were analyzed by Kruskal Wallis. Abundances of water strider related with environmental parameters were analyzed by GLM using a Poisson distribution, then followed by GLM using negative binomial distribution. Analyses were performed using program R 3.0.0. Results showed that three species of water striders were found in Ciliwung river, i.e. Ptilomera dromas Breddin, Limnogonus nitidus and Tenagogonus robustus. Gerrids, P. dromas was found in Ciliwung river in the fast current, while L. nitidus and T. robustus was found in slow current and tends to stagnant. In the Sempur station, both water strider species were found, i.e. L. nitidus and T. robustus in a puddle located on the edge of the river. The highest abundance of adult P. dromas was found in Katulampa (78.8 individuls), followed by Gadog (63.4 individuals), Cilember (41.0 individuals), and Cijulang (16.8 individuals) respectively. Cilember station has highest abundance of nymph of P. dromas (178.2 individuals), followed by Gadog (158.4 individuals), Katulampa (133.4 individuals), and Cijulang (80.2 individuals). The average of abundance of total P. dromas (adult and nymph) in Gadog station was highest (221.8 individuals), followed by Cilember (219.2 individuals), Katulampa (212.2 individuals), and Cijulang (97.0 individuals). P. dromas didn’t found in Sempur station. The ANOVA analysis showed that significant differences in water temperature (p=0.000), air temperature (p=0.000) dan pH (p=0.029) in each stations. The Tukey tests revealed significant
Keyword: Ptilomera dromas, abundance, Ciliwung river, water bioindicator

Judul: Status Kualitas Air Hulu Sungai Cihideung Menggunakan Makrozoobentos Sebagai Bioindikator
Abstrak: Aktivitas manusia dapat mempengaruhi kualitas perairan yang berpotensi menimbulkan pencemaran. Penelitian ini bertujuan untuk menentukan status kualitas air ruas hulu Sungai Cihideung berdasarkan makrozoobentos sebagai bioindikator. Penelitian ini dilakukan pada bulan April hingga Mei 2021 di hulu Sungai Cihideung, Kabupaten Bogor, Jawa Barat. Stasiun pengambilan contoh terdiri dari empat stasiun dengan masing-masing stasiun terdiri dari empat sub stasiun. Data yang digunakan dalam penelitian ini adalah kepadatan makrozoobentos, parameter fisika serta parameter kimia. Metode untuk penilaian status kualitas perairan menggunakan FBI (Family Biotic Index) dan SingScore. Hasil parameter fisika-kimia Sungai Cihideung masih sesuai dengan baku mutu PP No. 22 Tahun 2021. Makrozoobentos yang ditemukan terdiri dari 35 famili dan 49 genus. Komposisi seluruh stasiun didominasi oleh Ephemeroptera dari famili Baetidae. Indeks keanekaragaman yang didapat dari Stasiun 1 hingga Stasiun 4 adalah 3,01, 2,20, 1,54, dan 2,14 dengan kategori rendah. Indeks keseragaman dari Stasiun 1 hingga Stasiun 4 berturut turut adalah 0,71, 0,49, 0,34, dan 0,45 dengan kategori rendah hingga tinggi serta tidak ada jenis yang mendominasi (C<0,5). Hasil FBI menunjukkan kualitas perairan Sungai Cihideung tergolong sangat baik dengan rentang nilai 1,99-3,89. Hasil SingScore menunjukkan kualitas perairan rendah hingga sedang dengan rentang nilai 57,27-80,83., Human activities can affect water quality that has potential to cause pollution. This study aims to determine the water quality status of upstream section of Cihideung River based on macrozoobenthos as a bioindicator. This research was conducted from April to May 2021 in the upper reaches of Cihideung River, Bogor Regency, West Java. The sampling station consisted of four stations with each station consisting of four sub-stations. Data needed in this study are density, physical parameters and chemical parameters. Methods for assessing the status of water quality using FBI and SingScore. Results of physico-chemical parameters of Cihideung River still in accordance with PP No. 22/2021. The macrozoobenthos found consisted of 35 families and 49 genera. Composition of all stations is dominated by Ephemeroptera from Baetidae family. Diversity index obtained from Station 1-Station 4 is 3.01, 2.20, 1.54, and 2.14 with low categories. The uniformity index from Station 1-Station 4 was 0.71, 0.49, 0.34, and 0.45, respectively, with low-high categories and no dominant species (C<0.5). The results of FBI show that water quality of Cihideung River is classified as very good with value range of 1.99-3.89. SingScore results show low to moderate water quality with a value range of 57.27-80.83.
Keyword: Bioindicator, Cihideung River, Family Biotic Index, Macrozoobenthos, SingScore

Judul: Sifat operasi dan eksistensi invers suatu matriks dalam aljabar max-plus
Abstrak: Karya ilmiah ini membahas sifat-sifat operasi dalam aljabar max-plus dan sifat-sifat yang diaplikasikan pada matriks serta eksistensi invers matriks dalam aljabar max-plus. Operasi-operasi matriks yang dapat diaplikasikan dalam aljabar max-plus meliputi operasi penjumlahan dan perkalian antar matriks, matriks transpose, matriks identitas, matriks segi pangkat ke-k, serta perkalian matriks dengan skalar. Sifat- sifat yang berlaku untuk matriks dalam aljabar max-plus yaitu sifat asosiatif (untuk operasi penjumlahan dan perkalian), komutatif (hanya untuk operasi penjumlahan), dan distributif. Eksistensi invers suatu matriks a ∈ dalam aljabar max-plus dapat dipastikan ada jika dan hanya jika a merupakan perkalian matriks permutasi dan matriks diagonal . Max nxn p ( ) i d 
Keyword: matriks, aljabar max-plus