Makroavertebrata Bentos sebagai Bioindikator Kualitas Air Sungai Nimbai Manokwari, Papua Barat

Benthos macroinvertebrates have been used as bioindicators to assess the waters quality of the stream, but still are very rarely to applied in West Papua streams. Benthos macroinvertebrates can describe the stream water quality so that very well be used as bioindicators, due to each species has a different tolerance to interference organic pollutants in waters. This study aimed to assess the water quality of Nimbai stream using benthos macroinvertebrates tolerance level and several water quality parameters. Data retrieval was conducted in JuneJuly and SeptemberOctober 2012 in seven stations (L1L7) from Nimbai upstream to downstream that connected to Prafi river. The water macroinvertebrates were taken using surber with mesh size 200 μm and then was identified at the family level. At L5 station near the oil palm waste disposal installations was contains oil and fat (<1-3 mg/l), which resulted in dissolved oxygen (DO) and pH is lower than the other stations. Similarly the value of H' is low (0.83), however, the value of C (0.79) was high that dominated by Oligochaeta. Famili biotic index (FBI) value obtained showed that water quality in the L1L4 stations was in good to excellent condition, but the quality at L5 station is classified as very poor. As the distance far away from the sources of pollution in the L5 station, water quality tends to improve as shown in the L6 and L7 stations. The result of this study shows the important benefits of benthos macroinvertebrates as bioindicators for assessing the quality of stream waters, and can be described aquatic environments disturbance to the benthos macroinvertebrates habitats in Nimbai stream

Struktur Vegetasi Riparia dan Implikasinya Terhadap Kondisi Habitat Ikan Pelangi Arfak, Melanotaenia Arfakensis di Sungai Nimbai, Manokwari Papua Barat

Riparian vegetation has an important role in maintaining water stability, one of which is the river. This study aims to describe the structure of riparian vegetation so that its implications can be seen for the conditions of rainbow arfak habitat on the Nimbai River. The study was conducted in three forest types, namely primary riparia forest, secondary riparia forest and open riparia forest. Sample collection of riparian vegetation was carried out by purposive sampling using sample plots. Plots measuring 2 m x 2 m are used to sample seedling and understorey growth, plots measuring 5 m x 5 m for growth at the stake level, while plots measuring 10 m x 10 m and 20 m x 20 m, for growth of pole and tree levels respectively. The identification results obtained a total of 35 species of understorey and 51 tree-level plants in all three types of riparian forests. Based on the analysis of vegetation structure, it is known that the condition of primary riparia forest and secondary riparian forest still relatively supports the life of arfak rainbow fish compared to open riparian forest. Higher tree level density associated with canopy cover which has implications for the temperature of the water to be colder and less fluctuating, input larger litter into the food chain in the river, and hold suspended particles into the river. Also, the function of riparian vegetation in spawning activities, substrate attaching eggs and nursery habitat for arfak rainbow fish larvae. The results of this study indicate the importance of riparian vegetation structure on the condition of rainbow arfak fish habitat. An understanding of the structure of vegetation is also a basic information for efforts to rehabilitate this endemic fish habitat to maintain the existence of a natural population.Vegetasi riparia memunyai peran penting dalam menjaga kestabilan perairan, salah satunya adalah sungai. Penelitian ini bertujuan untuk mendeskripsikan struktur vegetasi riparia sehingga dapat diketahui implikasinya terhadap kondisi habitat ikan pelangi arfak di Sungai Nimbai. Penelitian dilakukan pada tiga tipe hutan, yaitu hutan riparia primer, hutan riparia sekunder dan hutan riparia terbuka. Pengumpulan contoh vegetasi riparia dilakukan secara purposif sampling menggunakan petak contoh. Petak berukuran 2 m x 2 m digunakan untuk mencuplik pertumbuhan tingkat semai dan tumbuhan bawah, petak ukuran  5 m x 5 m untuk pertumbuhan tingkat pancang, sedangkan petak ukuran 10 m x 10 m dan 20 m x 20 m, masing-masing untuk pertumbuhan tingkat tiang dan pohon. Hasil identifikasi diperoleh total 35 jenis tumbuhan bawah dan 51 tumbuhan tingkat pohon di ketiga tipe hutan riparia. Berdasarkan hasil analisis struktur vegetasi diketahui bahwa kondisi hutan riparia primer dan hutan riparia sekunder masih relatif mendukung kehidupan ikan pelangi arfak dibandingkan hutan riparia terbuka. Kerapatan tingkat pohon yang lebih tinggi berkaitan dengan tutupan tajuk yang berimplikasi terhadap suhu air menjadi lebih dingin dan kurang berfluktuasi, masukan serasah lebih besar ke rantai makanan di sungai, dan menyanggah partikel tersuspensi masuk ke sungai. Juga fungsi vegetasi riparia dalam aktivitas pemijahan, substrat penempelan telur dan habitat pembesaran larva ikan pelangi arfak. Hasil penelitian ini menunjukkan arti penting struktur vegetasi riparia terhadap kondisi habitat ikan pelangi arfak. Pemahaman mengenai struktur vegetasi juga menjadi informasi dasar bagi upaya rehabilitasi habitat ikan endemik ini untuk mempertahankan keberadaan populasinya alami

LAND COVER AND CARBON STORAGE IN A CERTIFIED SUSTAINABLE COMMUNITY FOREST IN SUMBEREJO VILLAGE, WONOGIRI, CENTRAL JAVA, USING LANDSAT DATA SERIES 2000, 2015 AND 2020

The Indonesian Ecolabel Institute certified Sumberejo Village’s 426.19 hectares of community forest as the first to receive a certificate of sustainable community forest management in 2004 for the first 15 years until 2019. Some economic, socio-cultural, and ecological aspects of this community forest management have been studied, but not the extent of land cover and the amount of carbon storage capacity. Indeed, this data is crucial in determining the role of certified community forests in climate change mitigation. Therefore, the purpose of this study is to look at the changes in land cover and the amount of carbon storage in Sumberejo Village’s community forest as a result of certification. Landsat 7 satellite images from the year 2000, Landsat 8 satellite images from 2015, and Landsat 8 satellite images from the year 2020 were used to represent the state-of-the-art community forest before, during, and the end of the certification period, respectively. Using a combination of the forest canopy density model and carbon storage conversion at the national level, we analyzed land cover classes from 2000 to 2015 and from 2015 to 2020, representing changes in the initial and final phases. The SPOT image 2020 land cover classification was then used as training data for a supervised classification-maximum likelihood algorithm to classify the images for 2000, 2015, and 2020. The result showed that moderately dense forest dominated the investigated area in 2000, followed by open forest and high dense forest, with 398.58 ha, 83.53 ha, and 35.53 ha, respectively. Total Carbon storage 45,230.02 tons C during this period. In 2015, moderately dense forest increased by 516.63 ha, while open forest significantly decreased by 4.73 ha as a result of tree planting activity, and high dense forest decreased by 1.69 ha as a result of harvesting. Due to public awareness of the need to manage and conserve forests through methodical harvesting, the composition of land cover, as well as carbon storage, remained unchanged in 2020. This consistent condition of carbon storage ensures that the certification has a positive impact on climate change mitigation. © 2022, University of Montenegro. All rights reserved