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Your search keyword '"Ida Adharini, Ratih"' showing total 2 results
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2 results on '"Ida Adharini, Ratih"'

1. The Variability of Surface Chlorophyll-a in Lake Rawa Pening within Five-Month Observations.

Author

Amelia, Karla, Nuringtyas, Satria Bagus, Setiawan, Riza Yuliratno, Setyobudi, Eko, Ida Adharini, Ratih, Aryudiawan, Candra, and Maslukah, Lilik

Subjects
CHLOROPHYLL in water, LAKE ecology, PHYTOPLANKTON, RAINFALL, ANTHROPOGENIC effects on nature
Abstract

Lake Rawa Pening is a natural lake in the Semarang Regency of Central Java Province, Indonesia, and its existence is pivotal to the surrounding communities as it provides ecological, economic, and social benefits. The ecosystem health of Rawa Pening can be represented by chlorophyll-a concentration because it indicates phytoplankton biomass, nutrient availability, and fish resources. Hence, the present study aims to disentangle the monthly variability of surface chlorophyll-a in Rawa Pening Lake by analyzing water samples that were collected once a month from nine stations within five-month observations (September 2020 to January 2021). The samples were analyzed using spectrophotometric method. Results showed that the highest surface chlorophyll-a concentration (23.33 mg/m3) took place in December, while the lowest concentration (12.64 mg/m3) occurred in October. The monthly variability of surface chlorophyll-a was likely controlled by variation of rainfall, with the highest (18.72 mm) and the lowest (12.33 mm) rainfall happened in December and October, respectively. The present study also indicates the anthropogenic activities such as agricultural activities, floating food stands, aquaculture, and tourist boats may contribute to surface chlorophyll-a variability in Rawa Pening Lake. [ABSTRACT FROM AUTHOR]

Published
2022
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2. Food Preference of Shortfin Scad (Decapterus macrosoma) at the Southern Waters of Gunungkidul Yogyakarta, Indonesia [Preferensi pakan ikan layang deles (Decapterus macrosoma) di Pantai Selatan Gunungkidul Yogyakarta]

Author

Lubis, Friyuanita, Ida Adharini, Ratih, and Setyobudi, Eko

Subjects
Decapterus macrosoma, Identification, Food preference, Gunungkidul, Trophic level
Abstract

The food habit is one of the important information used in the fisheries resource management. This study aimed to determine food preferences, index of preponderance, and trophic level of shortfin scad (D. macrosoma) captured from the southern waters of Gunungkidul Yogyakarta, Indonesia. A total of 325 fish samples were collected from March to September 2018. Each fish sample was measured in total length, body weight, determined its sex, and then dissected. The digestive tract was measured in total length then the gut contents were preserved in 5% formaldehyde to observe the type of food composition. The results showed that shortfin scad was carnivorous fish (relative gut length = 0.47) with the diet composing of fish (84.15%), phytoplankton (8.91%), zooplankton (4.47%), and snipping shrimp (3.19%). The molecular identification showed that the main fish species eaten by shortfin scad was Cololabis saira (Scomberesocoidae).AbstrakKebiasaan pakan ikan merupakan salah satu informasi penting yang digunakan dalam manajemen sumberdaya perikanan. Penelitian ini bertujuan untuk mengetahui preferensi pakan, indeks bagian terbesar dan tingkat trofik ikan layang deles (D. macrosoma) yang ditangkap dari Perairan Gunungkidul. Total 325 sampel ikan layang deles dikumpulkan selama bulan Maret sampai dengan September 2018. Setiap sampel ikan diukur panjang total, berat tubuh, ditentukan jenis kelaminnya kemudian dilakukan pembedahan. Saluran pencernaan diukur panjangnya, kemudian isi lambung ikan diawetkan dalam formalin 5% untuk diamati komposisi jenis makanannya. Analisis data meliputi panjang usus relatif, frekuensi kejadian, indeks bagian terbesar, dan tingkat trofik ikan layang deles. Hasil penelitian menunjukkan bahwa ikan layang deles bersifat karnivora (panjang usus relatif = 0,47) dengan komposisi jenis makanan utama adalah ikan (84,15%). Makanan pelengkap layang deles adalah fitoplankton (8,91%), sedangkan zooplankton (4,47%) dan potongan udang (3,19%) merupakan makanan tambahan. Berdasarkan identifikasi molekuler, spesies ikan yang menjadi makanan utama ikan layang deles adalah Cololabis saira (Scomberesocoidae).

Published
2019

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