bluuebunny/crossref_metadata_2025 huggingface dataset:
HUBUNGAN TEKSTUR SEDIMEN DENGAN MANGROVE DI DESA MOJO KECAMATAN ULUJAMI KABUPATEN PEMALANG
Authors: Aini Hida Rizki , Suryanto Agung , Hendrarto Boedi
Published: September 2020

ABSTRAK Desa Mojo merupakan salah satu wilayah Kecamatan Ulujami yang memiliki kawasan mangrove yang luas. Hutan mangrove di Desa Mojo merupakan hasil rehabilitasi yang dilakukan oleh masyarakat sekitar dan pihak terkait. Hutan mangrove Desa Mojo mempunyai fungsi yang sangat penting bagi daerah sekitarnya. Rehabilitasi yang telah dilakukan tersebut memberikan efek terhadap ekosistem. Habitat mangrove yang ada di Desa Mojo tersebut kemungkinan memberikan karakteristik terhadap sedimen sebaliknya karakteristik sedimen merupakan faktor penting terhadap keberadaan mangrove. Penelitian dilakukan pada bulan Maret – april 2016. Tujuan penelitian ini adalah untuk mengetahui hubungan karakteristik sedimen terhadap tegakan mangrove. Metode yang digunakan untuk menghitung kerapatan mangrove yaitu Point Centered Quarter Method. Karakteristik sedimen meliputi pengukuran fisika sedimen, pengukuran tekstur sedimen dengan metode Soil Jar Test (FAO), dan bahan organik sedimen diukur dengan metode LOI (Loss on Ignition). Hasil penelitian menunjukkan bahwa kondisi kawasan mangrove di Desa Mojo termasuk sangat padat, karena memiliki kerapatan lebih dari 1500 pohon per hektar (KepMenLH No.201, 2004). Sedimen pada kawasan mangrove Desa Mojo memiliki karakteristik tekstur silt (lumpur). Hasil Principal Component Analysis korelasi spesies mangrove dipengaruhi langsung oleh kuantitas silt dibandingkan dengan faktor lingkungan lainnya.  Kata Kunci : Tekstur sedimen; Mangrove; Ulujami; Pemalang ABSTRACT Mojo village is one of the District of Ulujamithat has extensive mangrove areas. The mangrove forest in the village of Mojo is the result of the rehabilitation undertaken by the local community and other interested parties. It has a very important function for the surrounding area. The rehabilitation has been done to give effect to the ecosystem. Mangrove habitat in the village of Mojo and sediment characteristics of mutrual influenced.. The study was conducted in March - April 2016. The purpose of this study was to determine the correlation characteristic of sediment to mangrove stands. The method used to calculate the density of mangrove namely Point Centered Quarter Method. Sediment characteristics include physical measurements of sediment, sediment texture measurement method Jar Test Soil (FAO), and sedimentary organic matter is measured by the method of LOI (Loss on Ignition). The results showed that the condition of the mangrove area in the village of Mojo include very dense, because it has a density of more than 1500 trees per hectare (KepMenLH 201, 2004). Sediment in the mangrove areas Desa Mojo has the characteristic texture of silt. The data used by the Principal Component Analysis correlation mangrove species were influenced by the quantity of silt, while there is no direct impact on other environmental factors on the existing mangrove species. Keywords: Sediment texture,Mangrove. Ulujami, Pemalang
STATUS TROFIK PERAIRAN BERDASARKAN NITRAT, FOSFAT, DAN KLOROFIL-a DI WADUK JATIBARANG, KOTA SEMARANG
Authors: Indriani Wening , Hutabarat Sahala , Ain Churun
Published: September 2020

ABSTRAKWaduk Jatibarang merupakan salah satu waduk yang berada di Semarang yang berfungsi sebagai wisata, sumber air bersih dan untuk mencegah banjir dengan  menampung air dari sungai Kaligarang dan sungai Kreo. Informasi tentang status trofik waduk ini sangat dibutuhkan untuk pengelolaan waduk Jatibarang di masa mendatang. Adapun tujuan penelitian ini adalah untuk mengetahui status trofik perairanberdasarkan kandungan nitrat (NO3), fosfat (PO4), dan klorofil-a di waduk Jatibarang. Hasil dari penelitian ini diharapkan sebagai acuan pengelolaan waduk Jatibarang. Waktu penelitian dilaksanakan pada tanggal 15 - 29 Maret 2016 dengan pengulangan sebanyak tiga kali dan rentan waktu satu minggu. Penentuan lokasi sampling pada penelitian ini mengacu pada perbedaan area waduk Jatibarang yang selanjutnya dibagi menjadi tiga stasiun pengamatan. Stasiun I sebagai area masukan (inlet), stasiun II di perairan tengah waduk dan stasiun III di area keluaran (Outlet). Setiap stasiun dilakukan pengambilan dua titik sampel berdasarkan kedalaman yaitu permukaan dan 10 meter. Hasil penelitian menunjukan bahwa status trofik waduk Jatibarang berdasarkan kandungan nitrat dan phospat eutrofik dan hipertrofik, sedangkan dilihat dari kandungan klorofil-a termasuk oligotrofik. Kata kunci : Status Trofik; Nitrat; Fosfat, Klorofil-a ; Waduk Jatibarang ABSTRACT Jatibarang reservoir is one of the reservoir located in Semarang which has a function as a Tourism, a source of clean water and to prevent flooding control to collect water from Kaligarang and Kreo river.. Information on the trophic status of the reservoir is very necessary for the future Management of Jatibarang reservoir. The purpose of this study was to determine the trophic status of waters by nitrate (NO3), phosphate (PO4) , and chlorophyll -a in the Jatibarang reservoir . The results of this study will be expected as a reference management of Jatibarang reservoir.The research was carried out on 15 to 29 March 2016, with the replication of three times with span period of one week.Determining the location of sampling in this study refers to the difference in the activity of Jatibarang reservoir area is further divided into three observation stations . Station I input area (inlet) , the second station in the middle of the reservoir waters and III stations in the output area (Outlet). Each station is done taking two sample points based on the depth of that surface and a depth of 10 meters. The results showed that the trophic status of the reservoir Jatibarang based content from nitrate and phosphate eutrophic and hypertrophic, while the views of chlorophyll-a, including oligotrophic. Keywords : Trophic Status;  Nitrate; Phosphate;  Chlorophyll – a;  Jatibarang Reservoir
KORELASI KONSENTRASI LOGAM Pb DAN Cd DENGAN STRUKTUR KOMUNITAS MAKROZOOBENTOS DI SUNGAI PLUMBON, MANGKANG, SEMARANG, JAWA TENGAH
Authors: Hafizulhaq M. , Haeruddin Haeruddin , Sedjati Sri
Published: September 2020

ABSTRAK Sungai Plumbon mempunyai potensi tingkat pencemaran yang cukup tinggi, dikarenakan berbagai aktivitas di sekitar sungai seperti rumah tangga, industri, dan tambak. Penelitian ini bertujuan untuk mengetahui konsentrasi logam Pb dan Cd dalam sedimen, struktur komunitas makrozoobentos, hubungan antara konsentrasi logam dengan kelimpahan makrozoobentos dan mengetahui status pencemaran berdasarkan kurva ABC. Metode sampling yang digunakan yaitu purposive sampling pada 3 stasiun dengan 2 kali sampling. Penelitian ini dilaksanakan pada bulan Mei – Juli 2015 di Sungai Plumbon, Mangkang, Semarang, Jawa Tengah. Hasil pengukuran logam Pb stasiun I berkisar antara 6,55 – 6,89 mg/kg, stasiun II berkisar antara 3,92 – 7,34 mg/kg, dan stasiun III berkisar antara 4,77 – 5,85 mg/kg dan nilai konsentrasi logam Cd pada stasiun I berkisar antara 1,35 mg/kg, nilai Cd stasiun II berkisar antara 1,63 – 2,13 mg/kg, nilai Cd stasiun III berkisar antara 2,09 – 2,47 mg/kg. Hasil uji makrozoobentos menunjukkan hasil kelimpahan individu dengan pada stasiun I 258.04-774,12 ind/m3, stasiun II 129,02-903,14 ind/m3 dan stasiun III 129,02-903,14 ind/m3. Uji korelasi yang dilakukan antara logam Pb dengan kelimpahan individu menghasilkan korelasi positif lemah dan logam Cd dengan kelimpahan menghasilkan korelasi negatif kuat. Ditinjau dari kurva ABC maka sungai Plumbon masuk dalam kategori sungai tergolong tercemar ringan hingga berat. Kata kunci : Logam Berat (Pb dan Cd); Makrozoobentos; Sungai Plumbon ABSTRACT Plumbon river has high potential of pollution level, because various activities around the river like: homes, industry, and aquacultures. This research aimed to knows concentration of Pb and Cd in sediments, community structure of macrozoobenthos, relation between metals concentration and macrozoobenthos abundance. Beside to know state of pollution based on ABC curve. The sampling method used purposive sampling on 3 stations with 2 sampling times. This research was carried out in May – July 2015 in the river Plumbon, Mangkang, Semarang, Central Java. The results of measurements of heavy metals Pb on station I are 6.55-6.89 mg/kg, station II are 3.92-7.34 mg/kg, and station III are 4.77-5.85. The results of the measurement of metal Cd on station I are 1.63-2.13 mg/kg, station II are 1.63-2.13 mg/kg, and station III are 2.09-2.47 mg/kg. Test results showed the abundance of individuals on station I are 258.04-774,12 ind/m3, station II are 129,02-903,14 ind/m3 and station III are 129,02-903,14 ind/m3. Correlation test conducted between metal Pb with individual abundance show weak and positive correlation and metal Cd with individual abundance show strong and negative correlation. Based on ABC curve, Plumbon river is categorized as moderately to heavily polluted river. Keywords: Heavy Metal (Pb and Cd); Macrozoobenthos; Plumbon River
ANALISIS MORFOMETRI, JENIS DAN SEBARAN TANGKAPAN IKAN MANYUNG DI PELABUHAN PERIKANAN NUSANTARA PEKALONGAN (Morphometric Analysis, Species and Catch Distribution of Manyung Fish in Pekalongan Domestic Fishing Port Pekalongan)
Authors: Marbun April Yani , Ghofar Abdul , Solichin Anhar
Published: September 2020

Ikan Manyung merupakan salah satu jenis ikan pantai di Laut Jawa yang termasuk dalam kelompok ikan demersal dan jenis ikan lepas pantai. Pada tahun 2011, produksi Ikan Manyung di Indonesia mencapai 90.980 ton dan merupakan produksi terbesar untuk golongan ikan demersal. Sebagai tindak lanjut dan menjaga keseimbangan ekosistem, maka diperlukan monitoring. Penelitian bertujuan untuk mengetahui analisis morfometri, jenis, serta sebaran tangkapan Ikan Manyung. Penelitian dilaksanakan pada bulan 21 April-13 Mei 2017 di Pelabuhan Perikanan Nusantara Pekalongan, Jawa Tengah. Metode penelitian yang digunakan yaitu metode survey dan pengambilan sampel dilakukan dengan cara purposive sampling. Dari hasil penelitian terdapat 2 jenis Ikan Manyung yang didaratkan yaitu Manyung Utik (Arius thalasinus) dan Manyung Pidada (Arius maculatus). Sebaran titik koordinat penangkapan berada pada kisaran lintang 05048’74.8” sampai 06056’10” dan bujur 109054’49.3” sampai 110045’39.6”. Daerah sebaran titik tangkap berada di daerah Kota Pekalongan, Batang, Kendal, Demak, Semarang dan Jepara. Manyung fish is one of java island species includes as demersal and off shore fish. In 2011, total fish production in Indonesia reached 90,980 tons and is the largest production for demersal fish group. As a follow up of this and maintain the balance of the ecosystem, it is necessary monitoring. The study was aimed to determine the morphometric analysis, species and catch distribution of manyung fish.  The study was conducted in 21 April-13 May 2016 at the Pekalongan Domestic Fishing Port, Central Java This research used survey method and sampling was done by a purposive sampling. There were 2 species of manyung were landed, there are Manyung Utik (Arius thalasinus) and Manyung Pidada (Arius maculatus). Distribution of fishing coordinate point was in the range of latitude 05048'74.8 until 06056'10" and the longitude 109054'49.3" until 110045'39.6". The catch distribution is located in Pekalongan, Batang, Kendal, Demak, Semarang and Jepara.
VALUASI EKONOMI OBJEK WISATA TREKKING MANGROVE, GRAND MAERAKACA TAMAN MINI JAWA TENGAH DAN POTENSI PENGEMBANGANNYA
Authors: Alviani Nadya Nurita , Suprapto Djoko , Wijayanto Dian
Published: September 2020

Grand Maerakaca merupakan salah satu objek wisata yang ada di Semarang, yang memiliki daya tarik yaitu Trekking Mangrove. Penelitian ini bertujuan untuk mengetahui karakteristik penggunjung, persepsi pengunjung mengenai potensi pengembangan objek wisata dan menghitung nilai ekonomi Objek Wisata Trekking Mangrove menggunakan metode Travel Cost Method (TCM) dan Willingness to Pay (WTP). Jumlah responden dalam penelitian ini adalah 100 orang. Teknik pengambilan data pada penelitian ini menggunakan Convinience Sampling. Hasil penelitian menunjukkan bahwa karakteristik pengunjung Objek Wisata Trekking Mangrove, Grand Maerakaca mayoritas adalah pelajar/mahasiswa dan karyawan swasta yang berumur 15-25 tahun, menggunakan alat transportasi sepeda motor, melakukan kunjungan bersama keluarga dengan tujuan berlibur. Persepsi pengunjung mengenai potensi pengembangan adalah bahwa Objek Wisata Trekking Mangrove memiliki daya tarik paling tinggi dan harga yang terjangkau menjadi faktor penentu utama kunjungan. Sedangkan penambahan wisata pengembangan yang paling berpotensi dengan estimasi pengguna tertinggi adalah edukasi penanaman mangrove dengan nilai WTP sebesar Rp. 5.000,00. Nilai ekonomi Objek Wisata Trekking Mangrove, Grand Maerakaca dengan metode TCM sebesar Rp. 45.779.385.645,00/tahun dan Nilai WTP wahana perahu sampan, wahana perahu motor, tiket masuk, tiket parkir motor dan tiket parkir mobil adalah Rp. 10.000,00, Rp. 5.000,00, Rp. 10.000,00, Rp. 2.000,00, dan Rp. 5.000,00.  The Grand Maerakaca is one of the tourist destination in Semarang, that have attraction is Tracking Mangrove. The purpose of this study are to know the characteristics of the visitors, the visitor's perception about the potential of tourism development and to calculate the economic value of Trekking Mangrove Object using Travel Cost Method (TCM) and Willingness to Pay (WTP) method. The number of respondents in this study are 100 people. Technique of taking data in this research using Convinience Sampling. The results showed that the visitors characteristics of Tracking Mangrove Tourism Object, Grand Maerakaca majority are students and private employees aged 15-25 years, use motorbike transportation, come with their family on the purpose of vacation. The visitor perception on potential development are the highest attraction of Tracking Mangrove and affordable price to be the main determinant factor of visitation. While addition of the most potential development tours with the highest user estimation is education of mangrove planting with a WTP value of IDR. 5,000. Economic value of Mangrove Trekking Tourism Object, Grand Maerakaca with TCM method is IDR. 45,779,385,645/ year and WTP Value boat ride, motorboat ride, entrance ticket, motorcycle parking ticket and car parking ticket is IDR. 10,000., IDR. 5,000., IDR. 10,000., IDR. 2,000 and IDR. 5,000.
ANALISIS HUBUNGAN JARAK DAN KEDALAMAN DENGAN STRUKTUR KOMUNITAS LAMUN DI PANTAI PANCURAN, KEPULAUAN KARIMUNJAWA
Authors: Ridho Muhammad Gaffar , Supriharyono Supriharyono , Rahman Arif
Published: September 2020

Pantai Pancuran adalah salah satu lokasi konservasi padang lamun di Taman Nasional Karimunjawa dengan vegetasi padang lamun. Penelitian ini dilaksanakan pada bulan April 2018 dengan tujuan untuk mengetahui hubungan jarak dan kedalaman dengan struktur komunitas lamun yang meliputi kerapatan dan indeks keanekaragamannya. Materi yang digunakan adalah lamun, dengan menggunakan metode deskripsi eksploratif yang bersifat observasi dengan objek yang diteliti di lapangan. Teknik pengambilan sampel menggunakan kuadran transek ukuran 1x1 meter yang tersebar di 3 stasiun berdasarkan jarak dan kedalaman serta terdapat 6 plot pada setiap stasiunnya. Parameter lingkungan yang diamati meliputi jarak dan kedalaman, nitrat dan fosfat sedimen, salinitas, suhu, derajat keasaman (pH), kecerahan, kecepatan arus, pasang surut, dan karakteristik sedimen. Hubungan jarak dan kedalaman dengan struktur komunitas lamun diproses menggunakan analisis regresi dan korelasi. Hasil penelitian ini didapatkan 6 jenis lamun yaitu Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis, Syringodium isoetifolium, Enhalus acoroides, dan Halodule pinifolia. Karakteristik sedimen didominasi oleh pasir halus sebanyak 34,960 %. Korelasi jarak dan kedalaman dengan struktur komunitas lamun diperoleh nilai                 (r = -0,717) pada kerapatan dan ( r = 0,894) pada indeks keanekaragaman.                  Pancuran Beach is one of the seagrass conservation areas in Karimunjawa National Park. This study was conducted in April 2018, in order to investigate the relation of distance and depth on the structure of seagrass community which included the density and index of diversity. The method used in this study is seagrass, using explorative description method that is observation to the object study in the field. The sampling technique uses a 1x1 meter transect quadrant spread over 3 stations based on distance and depth with includes 6 plots at each station. Environmental parameters observed include distance and depth, sediment of nitrate and phosphate, salinity, temperature, acidity (pH), brightness, current velocity, tides, and sediment characteristics. The relationship between distance and depth on the structure of seagrass community processed by regression and correlation analysis . The results of the study found 6 types of seagrass, there were Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis, Syringodium isoetifolium, Enhalus acoroides, and Halodule pinifolia. Sediment characteristics were dominated is fine sand of 34.960%. The correlation of distance and depth on the structure of seagrass community resulted a value (r = -0,717) for density and  (r = 0,894) for index of diversity.
PENGARUH KERAPATAN LAMUN Thalassia hemprichii TERHADAP KELIMPAHAN BAKTERI HETEROTROF DI PANTAI PRAWEAN, JEPARA
Authors: Yunita Isnaini Dian , Widyorini Niniek , Supriharyono Supriharyono
Published: September 2020

Ekosistem lamun merupakan salah satu ekosistem yang memiliki kompleksitas dan keanekaragaman hayati yang tinggi. Padang lamun merupakan hamparan vegetasi lamun yang menutupi suatu kawasan pesisir. Selain memiliki fungsi ekonomi, lamun juga memiliki fungsi ekologis yakni berperan penting sebagai pendaur zat hara oleh mikroorganime yaitu bakteri. Penelitian ini bertujuan untuk mengetahui kerapatan lamun, kelimpahan bakteri heterotrof yang berasosiasi dengan lamun serta pengaruh kerapatan lamun dengan kelimpahan bakteri heterotrof di Pantai Prawean, Jepara. Metode yang digunakan yakni deskriptif eksplanatif dengan pengambilan sampel secara purposive dan dianalisis dengan IBM SPSS Statistic 22. Jenis lamun yang ditemukan di Pantai Prawean ada 5 (lima): Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halodule uninervis dan Halodule pinifolia. Kerapatan tertinggi didapat dari jenis Thalassia hemprichii sebesar 78 Ind/m2 dan terendah adalah Enhalus acoroides 10 Ind/m2 dan kelimpahan bakteri heterotrof tertinggi diperoleh dari tingkat kerapatan rapat di stasiun 3 yakni 29,4x108 Upk/ml dan kelimpahan terendah diperoleh dari tingkat kerapatan jarang di stasiun 2 yakni 3,3x108 Upk/ml. Korelasi antara kerapatan lamun dengan kelimpahan bakteri heterotrof tinggi atau kuat yakni 0,896 dan korelasi ini dinyatakan sangat signifikan terbukti nilai sig. 0,001 dengan tingkat kesalahan 0,1%. Artinya bertambahnya kerapatan lamun dapat meningkatkan pula kelimpahan bakteri heterotrof. Seagrass ecosystem is one ecosytems that has high complexity and biodiversity. Seagrass beds are a stretch of seagrass vegetation that covers a coastal area. Beside its economic function, seagrass also have ecological function that play an important role of nutrient cycle for microorganism its bacteria. This study aims to determine the density of seagrass, the abundance of heterothropic bacteria and influence of seagrass density with abundance of heterotrophic bacteria at Prawean beach, Jepara. The method used in this study is descriptive explanative with purposive sampling and the data analyzed by IBM SPSS Statistic 22. There are 5 (five) species of seagrass that can be found in Prawean beach: Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halodule uninervis and Halodule pinifolia. The highest density obtained from Thalassia hemprichii species is 78 sprouts of seagrass/m2 and the lowest density obtained from Enhalus acoroides is 10 obtained from seagrass density at station 3 its value 29,4x108Cfu/ml and the lowest abundance of heterotrophic bacteria was obtained from rare seagrass at station 2 its value 3,3x108Cfu/ml.  The corelation between seagrass density with abundance heterotrophic bacteria is high or strong that has value 0,846 and this correlation is very significantly proven has sig value 0,001 with error rate 0,1%, it can be conclude that increase of seagrass density can also increase the abundance of heterotrophic bacteria.
Valuasi Ekonomi Sumberdaya Ikan Dan Ekowisata Mangrove Di Muara Angke, Jakarta
Authors: Mahardhika Septya Mega , Saputra Suradi Wijaya , Ain Churun
Published: September 2020

Muara Angke merupakan satu – satunya kawasan yang masih memiliki ekosistem mangrove di daerah pesisir Jakarta. Luas Muara Angke kurang lebih 964,98 ha dibagi menjadi tiga zona. Dua diantaranya berkontribusi pada sektor Perikanan dan Ekowisata, yaitu Pangkalan Pendaratan Ikan (PPI) dan Taman Wisata Alam Angke Kapuk (TWAAK). Kurangnya pemahaman umum tentang manfaat ekonomi ekosistem mangrove  menyebabkan masyarakat mengeksploitasi secara berlebihan sehingga terjadi perubahan penggunaan lahan. Tujuan penelitian ini untuk mengetahui nilai ekonomi yang dihasilkan ekosistem mangrove berdasarkan dua aspek yaitu Perikanan Tangkap dan Ekowisata. Data Perikanan Tangkap menggunakan data sekunder dari Pengelola PPI Muara Angke tahun 2016 – 2017. Data sosial ekonomi diperoleh menggunakan  wawancara dengan bantuan kuesioner. Data biaya perjalanan rata – rata diperoleh dengan wawancara pengunjung TWAAK. Analisis Valuasi Ekonomi Perikanan Tangkap menggunakan Market Price Method. Analisis Valuasi Ekonomi Ekowisata Mangrove menggunakan Travel Cost Method. Metode penentuan 100 responden nelayan tangkap menggunakan Random Sampling sedangkan penentuan 100 responden pengunjung TWAAK menggunakan Accidental Sampling. Hasil penelitian didapatkan nilai ekonomi pada aspek perikanan tahun 2016 Rp. 13.148.945.100, tahun 2017 Rp.21.087.388.300 dan tahun 2018 Rp. 370.313.869.500. Hasil penelitian didapatkan nilai ekonomi ekowisata tahun 2018 Rp.40.28.400.000 Muara Angke is the only area that still has mangrove ecosystems in the coastal areas of Jakarta. Muara Angke area is approximately 964.98 ha divided into three zones. Two of them contribute to the Fisheries and Ecotourism sector, namely Fish Landing Base (PPI) and Angke Kapuk Nature Park (TWAAK). Lack of general understanding of the economic benefits of mangrove ecosystems causes people to over-exploit so that land use changes occur. The purpose of this study was to determine the economic value generated by mangrove ecosystems based on two aspects, namely Capture Fisheries and Ecotourism. Capture Fisheries Data uses secondary data from Muara Angke PPI Manager in 2016 - 2017. Socio-economic data were obtained using interview with Muara Angke fishermen with questionnaire assistance. Average travel cost data is obtained by interviewing TWAAK visitors. Capture Fisheries Economic Valuation Analysis using Market Price Method. Economic Valuation Analysis of Ecotourism Mangroves use the Travel Cost Method. The method of determining 100 respondents of capture fishermen uses Random Sampling while the determination of 100 respondents of TWAAK visitors uses Accidental Sampling. The results of the study obtained economic value in aspects of fisheries in 2016 Rp. 13,148,945,100, in 2017 Rp.21,087,388,300 and in 2018 Rp. 370,313,869,500. The results of the study obtained the economic value of ecotourism in 2018 Rp. 40.28.400.000
HUBUNGAN KONSENTRASI NITRAT DAN FOSFAT DENGAN KELIMPAHAN FITOPLANKTON DI WADUK JATIBARANG, SEMARANG The Conection Of Nitrate and Phospat with Abundance of Phytoplankton In Jatibarang Resevoir City Of Semarang
Authors: Marsaoly Micail , Supriharyono Supriharyono , Rudiyanti Siti
Published: September 2020

ABSTRAK Waduk Jatibarang merupakan salah satu waduk yang berada di Semarang yang berfungsi sebagai wisata, sumber air bersih dan untuk mencegah banjir dengan menampung air dari sungai Kaligarang dan sungai Kreo. Informasi tentang status trofik waduk ini sangat dibutuhkan untuk pengelolaan waduk Jatibarang di masa mendatang. Adapun tujuan penelitian ini adalah untuk mengetahui status trofik perairanberdasarkan kandungan nitrat (NO3), fosfat (PO4), dan klorofil-a di waduk Jatibarang. Hasil dari penelitian ini diharapkan sebagai acuan pengelolaan waduk Jatibarang. Penentuan lokasi sampling pada penelitian ini mengacu pada perbedaan area waduk Jatibarang yang selanjutnya dibagi menjadi tiga stasiun pengamatan. Stasiun I sebagai area masukan (inlet), stasiun II di perairan tengah waduk dan stasiun III di area keluaran (Outlet). Setiap stasiun dilakukan pengambilan dua titik sampel berdasarkan kedalaman yaitu permukaan dan. Hasil penelitian menunjukkan bahwa status trofik waduk Jatibarang berdasarkan kandungan nitrat tergolong eutrofik dengan kisaran nilai 0,866-1,314 mg/l. Fosfat adalah hipertrofik dengan kisaran nilai 2,960-5283 mg/l. Sedangkan dilihat dari kandungan klorofil-a termasuk oligotrofik dengan kisaran nilai 1,471-2,273 mg/l. hubungan antara kelimpahan fitoplankton dengan nitrat dan fosfat masing-masing lemah dan sangat lemah. ABSTRACTJatibarang reservoir is one of the reservoir located in Semarang which has a function as a Tourism, a source of clean water and to prevent flooding control to collect water from Kaligarang and Kreo River. Information on the trophic status of the reservoir is very necessary for the future Management of Jatibarang reservoir. The purpose of this study was to determine the trophic status of waters by nitrate (NO3), phosphate (PO4), and chlorophyll-a in the Jatibarang reservoir. The results of this study will be expected as a reference management of Jatibarang reservoir. Determining the location of sampling in this study refers to the difference in the activity of Jatibarang reservoir area is further divided into three observation stations . Station I input area (inlet) , the second station in the middle of the reservoir waters and III stations in the output area (Outlet). Each station is done taking two sample points based on the depth of that surfaces. The results showed that the trophic status of the reservoir Jatibarang based content from nitrate is oligotrophic with score 0,866-1,314 mg/l. Phospate concentration is hypertrophic with 2,960-5283 mg/l range. Despite Chlorophyl-a is oligotrophic with 1,471-2,273 mg/l. based on Abundance of phytoplankton on the reservoir Jatibarang Classified as Moderat, and the correlation between Abundance of phytoplankton with nitrate and phosphate are weak and correlated weakly.
ANALISIS KESUBURAN PERAIRAN BERDASARKAN KEPADATAN DAN JENIS PERIFITON DI SUNGAI JABUNGAN, BANYUMANIK, SEMARANG Analysis of Water’s Trophic State Based on Periphyton’s Abundance and Types in Jabungan River, Banyumanik, Semarang
Authors: Agustin Arninda Dwi , Solichin Anhar , Rahman Arif
Published: September 2020

ABSTRAK Sungai Jabungan merupakan salah satu sungai di Kota Semarang yang banyak dimanfaatkan untuk aktivitas sehari-hari seperti pemukiman, pertanian, dan perkebunan sehingga mempengaruhi kesuburan perairan. Kesuburan perairan sungai dapat diketahui dengan menghitung kepadatan perifiton yang ada di perairan. Tujuan dari penelitian ini untuk mengetahui kepadatan dan hubungan antara perifiton dengan kandungan nitrat fosfat, serta mengetahui tingkat kesuburan perairan Sungai Jabungan, Banyumanik, Kota Semarang. Penelitian ini dilaksanakan pada bulan Maret 2019 di Sungai Jabungan, Banyumanik, Kota Semarang. Metode yang digunakan dalam penelitian ini adalah metode purposive sampling di tiga stasiun berbeda yaitu stasiun 1 persawahan, stasiun 2 daerah alami, dan stasiun 3 pemukiman. Analisis data menggunakan metode regresi linier berganda. Hasil yang diperoleh yaitu diperoleh 17 genera perifiton dari kelas Bacillariophyceae dan 2 genera dari kelas Cyanophycea dengan kapadatan stasiun 1 sebesar 118.379 individu/cm2, stasiun 2 sebesar 85.324 individu/cm2, dan stasiun 3 sebesar 110.925 individu/cm2. Kandungan nitrat berkisar antara 3,13–3,67 mg/l dan fosfat berkisar antara 0,93–1,33 mg/l. Hubungan kepadatan perifiton dengan kandungan nitrat dan fosfat lemah dengan nilai korelasi 0,28. Tingkat kesuburan di Sungai Jabungan termasuk dalam kategori mesotrofik (kesuburan sedang) hingga eutrofik (kesuburan tinggi). ABSTRACT Jabungan River is one of several rivers in Semarang City that used for daily activities that affect water quality. One of several ways to know the water’s trophic state is counting the abundance of periphyton. The aim of this research is to know the abundance and correlation between periphytons with nitrate and phosphate, and also to know the water’s level of productivity in Jabungan River, Banyumanik, Semarang City. This research was conducted in March 2019 in Jabungan River, Banyumanik, Semarang City. The method in this research is purposive sampling. Data analysis using multiple linear regression methods. The results show 17 genera of periphytons from Bacillariophyceae and 2 genera from Cyanophycea. The abundance in line 1 were 118.379 organisms/cm2, line 2 were 85.324 organisms/cm2, and line 3 were 110.925 organisms/cm2. The number of nitrates were about 3,13–3,67 mg/l and phosphates were about 0,93–1,33 mg/l. The correlation between periphyton’s abundance and nitrate phosphate is weak with the number of correlation was 0,28. The water’s trophic state in Jabungan River between mesotrophic until eutrophic.
Hubungan antara Nitrat dan Fosfat dengan Kelimpahan Fitoplankton di Waduk Jatibarang Semarang Correlation between Nitrate and Phospate with Abundance of Phytoplankton in Jatibarang Reservoir, Semarang
Authors: Ikhsan Muhammad Khoirul , Rudiyanti Siti , Ain Churun
Published: September 2020

ABSTRAK Waduk Jatibarang merupakan salah satu waduk yang memiliki peran penting di Kota Semarang sehingga kualitas perairannya perlu diperhatikan. Keberadaan fitoplankton di perairan berkaitan erat dengan kesuburan dan kualitas suatu perairan dikarenakan fitoplankton berperan sebagai produsen primer. Tujuan penelitian ini untuk mengetahui kualitas perairan berdasarkan kelimpahan fitoplankton serta melihat sejauh mana korelasi nitrat dan fosfat akan mempengaruhi kelimpahan fitoplankton diperairan. Penelitian dilakukan pada tanggal 27 Maret 2019 di Waduk Jatibarang semarang. Pengambilan sampel dilakukan menggunakan metode purposive sampling di tujuh stasiun dengan tiga titik kedalaman (permukaan, tengah dan dasar perairan) dan tiga pengulangan (pagi, siang dan malam). Pengolahan data menggunakan program SPSS 25 dengan analisis regresi liner berganda. Konsentrasi nitrat yang didapatkan berkisar antara 0,45-9,64 mg/l, konsentrasi fosfat berkisar antara 1,26-4,81 mg/l, kelimpahan fitoplankton berkisar antara 1.667 – 275.833 ind/l. Hubungan antara konsentrasi nitrat dan fosfat dengan kelimpahan fitoplankton tergolong lemah dengan koefisien korelasi (r = 0,378). Nitrat dan fosfat mempengaruhi kelimpahan fitoplankton sebesar 15% dengan koefisien determinasi (r square = 0,150). Tingkat kesuburan di Waduk Jatibarang termasuk dalam kategori mesotrofik hingga eutrofik berdasarkan konsentrasi nitrat, fosfat dan kelimpahan fitoplankton. ABSTRACT Jatibarang Reservoir is one of the reservoirs that has an important role in the city of Semarang so that the quality of its waters needs to be considered. The presence of phytoplankton in waters is closely related to the fertility and quality of a waters because phytoplankton act as primary producers. The purposes of this research are to determine the quality of water based on the consentration of nitrate and phosphate, to calculate the abundance of phytoplankton and also to know the correlation of nitrates and phosphate toward the abundance of phytoplankton. The research was conducted on 27 March 2019 in Jatibarang Reservoir Semarang. Sampling was carried out at seven stations with three depth points (surface, middle and bottom) and three repetitions (morning, day and night). Data processing using SPSS 25 programme with multiple liner regression analysis. The concentration of nitrate gained ranged from 0.45 - 9.64 mg/l, phosphate concentrations ranged from 1.26 - 4.81 mg/l, the abundance of phytoplankton ranges between 1,667 – 275,833 ind/l. The relationship between nitrate and phosphate concentrations with an abundance of phytoplankton is relatively weak with a correlation coefficient (r = 0.378). Nitrates and phosphates affect the abundance of phytoplankton by 15% with coefficient of determination (r square = 0.150). Water’s trophic state in the Jatibarang reservoir belongs to the mesotrophic up to Eutrophic category.
Novices’ performance using hypertext materials: Shedding light on disorientation
Authors: Jáñez Álvaro , Rosales Javier
Published: September 2020

Many researchers have proposed a causal link between low domain knowledge and disorientation in hypertext. Our objective was to challenge this hypothesis, examining other variables that might have an influence, such as design, reading instructions, or working memory capacity. We analysed navigation patterns and comprehension scores in a sample of low topic knowledge undergraduate students (N = 45) who were assigned to one of three hypertext conditions: reading for a test, reading to write a summary, and elaborative interrogation. Another sample (N = 45) of low knowledgeable undergraduate students were used as a control group, performing the same tasks using printed texts. Regarding disorientation, and contrasting with previous research, only a minority of students became disoriented in hypertext. Neither reading instructions nor working memory capacity had the expected impact on readers’ behaviour or outcomes, so hypertext design might be a key aspect on explaining disorientation. Implications for hypertext design and education are discussed.

 

Implications for practice or policy:

The general assumption of low prior knowledge readers becoming disoriented in hypertext is falsified.

Educational hypertext designers should always consider hypertext structure, graphical overviews, and usability elements.

Educators must be aware that novices may show difficulties to adapt their learning behaviour to different reading goals.
Learn from your environment: A visual literacy learning model
Authors: Guinibert Matthew
Published: September 2020

Based on the presupposition that visual literacy skills are not usually learned unaided by osmosis, but require targeted learning support, this article explores how everyday encounters with visuals can be leveraged as contingent learning opportunities. The author proposes that a learner’s environment can become a visual learning space if appropriate learning support is provided. This learning support may be delivered via the anytime and anywhere capabilities of mobile learning (m-learning), which facilitates peer learning in informal settings. The study propositioned a rhizomatic m-learning model of visual skills that describes how the visuals one encounters in their physical everyday environment can be leveraged as visual literacy learning opportunities. The model was arrived at by following an approach based on heuristic inquiry and user-centred design, including testing prototypes with representative learners. The model describes one means visual literacy could be achieved by novice learners from contingent learning encounters in informal learning environments, through collaboration and by providing context-aware learning support. Such a model shifts the onus of visual literacy learning away from academic programmes and, in this way, opens an alternative pathway for the learning of visual skills.

 

Implications for practice or policy:

This research proposes a means for learners to leverage visuals they encounter in their physical everyday environment as visual literacy learning opportunities.

M-learning software developers may find the pedagogical model useful in informing their own software.

Educators teaching visual skills may find application of the learning model’s pedagogical assumptions in isolation in their own formal learning settings.
Leibniz and the ‘petites réflexions’
Authors: Bender Sebastian
Published: September 2020

In this article, I defend the thesis that Leibniz’s rational substances always have higher-order perceptions, even when they are, say, in a dreamless sleep. I argue that without this assumption, Leibniz’s conception of reflection would introduce discontinuities into his philosophy of mind which (given his Principle of Continuity) he cannot allow. This interpretation does not imply, however, that rational beings must be aware of these higher-order states at all times. In fact, these states are often unconscious or ‘small’ (analogous to Leibniz’s famous petites perceptions) and only count as reflections when they become distinct or heightened enough. Reflections thus arise out of ‘petites réflexions’ just as conscious perceptions arise out of petites perceptions. I argue, furthermore, that an analysis of some aspects of Leibniz’s theory of memory shows that he is not only committed to the thesis that rational beings always have higher-order states but that he also accepts it. I conclude by considering whether my interpretation is at odds with Leibniz’s doctrine of transcreation and also whether it has any consequences for which theory of consciousness we should ascribe to Leibniz.
Marginal quantile regression for longitudinal data analysis in the presence of time-dependent covariates
Authors: Chen I-Chen , Westgate Philip M.
Published: September 2020

When observations are correlated, modeling the within-subject correlation structure using quantile regression for longitudinal data can be difficult unless a working independence structure is utilized. Although this approach ensures consistent estimators of the regression coefficients, it may result in less efficient regression parameter estimation when data are highly correlated. Therefore, several marginal quantile regression methods have been proposed to improve parameter estimation. In a longitudinal study some of the covariates may change their values over time, and the topic of time-dependent covariate has not been explored in the marginal quantile literature. As a result, we propose an approach for marginal quantile regression in the presence of time-dependent covariates, which includes a strategy to select a working type of time-dependency. In this manuscript, we demonstrate that our proposed method has the potential to improve power relative to the independence estimating equations approach due to the reduction of mean squared error.
Convexity properties of the normalized Steklov zeta function of a planar domain
Authors: Jollivet Alexandre
Published: September 2020

We consider the zeta function

ζ
Ω

\zeta_{\Omega}

for the Dirichlet-to-Neumann operator of a simply connected planar domain Ω bounded by a smooth closed curve of perimeter

2
⁢
π

2\pi

.
We name the difference

ζ
Ω

-

ζ
D

\zeta_{\Omega}-\zeta_{\mathbb{D}}

the normalized Steklov zeta function of the domain Ω, where 𝔻 denotes the closed unit disk.
We prove that

(

ζ
Ω

-

ζ
D

)

′′

⁢

(
0
)

≥
0

(\zeta_{\Omega}-\zeta_{\mathbb{D}})^{\prime\prime}(0)\geq 0

with equality if and only if Ω is a disk.
We also provide an elementary proof that, for a fixed real 𝑠 satisfying

s
≤

-
1

s\leq-1

, the estimate

(

ζ
Ω

-

ζ
D

)

′′

⁢

(
s
)

≥
0

(\zeta_{\Omega}-\zeta_{\mathbb{D}})^{\prime\prime}(s)\geq 0

holds with equality if and only if Ω is a disk.
We then bring examples of domains Ω close to the unit disk where this estimate fails to be extended to the interval

(
0
,
2
)

(0,2)

.
Other computations related to previous works are also detailed in the remaining part of the text.
The impact of the COVID-19 pandemic on the perinatal mental health of women
Authors: Farrell Tom , Reagu Shuja , Mohan Suruchi , Elmidany Riham , Qaddoura Feras , Ahmed Ebtehag Elfadil , Corbett Gillian , Lindow Stephen , Abuyaqoub Salwa Mohammed , Alabdulla Majid Ali
Published: September 2020

Objectives

The physical health impact of the coronavirus disease infection (COVID-19) has received attention worldwide; however, data around the psychological impact of the pandemic is still emerging and little has been reported on psychological effects among vulnerable groups. This study was undertaken with the aim of studying the impact of the COVID-19 pandemic and related restrictions on perinatal mental health among women in Qatar.

Methods

A cross- sectional survey of women accessing maternity services in Qatar was carried out during the months of June and July 2020 at the local peak of the pandemic. Background data including relevant demographic details, pregnancy and mental health history, concerns, as well as helpful stress-reducing factors reported by women was collected. Depression and anxiety symptomatology was studied using the Patient Health Questionnaire Anxiety-Depression Scale (PHQ-ADS).

Results

The survey results revealed a high prevalence of anxiety and Depressive symptomatology (34.4 and 39.2% respectively), based on PHQ-ADS scoring. These rates appeared much higher than the reported pre-pandemic prevalence and were not affected by occupation, previous mental health problems or pregnancy complications. Women’s most commonly reported concerns as well as coping factors are discussed.

Conclusions

Results indicate a marked increase in anxiety and depressive symptoms during the COVID-19 pandemic, among pregnant and puerperal individuals, who constitute a vulnerable group with respect to mental health morbidity. These findings can be used to inform public health interventions, among which, consideration should be given to routine mental health screening of vulnerable groups during major health crises.
Actuality bias in verb learning: The case of sublexically modal transfer verbs
Authors: Kazanina Nina , Baker Sara , Seddon Hayley
Published: September 2020

The study investigates semantic development of sublexically modal verbs of transfer,throwandsend, in English-speaking children. For adults, sublexical modality of these verbs can be seen in the fact that the subevent of transfer of the object to the recipient need not take place in the actual world, e.g.Mary sent/threw a book to Johndoes not entail a successful transfer of the book to John. Yet in two experiments (Experiment 1: 3–4 year-olds,N = 59; Experiment 2: 3–6 year olds,N = 120) young English-speaking children often misinterpretedMary sent a book to Johnas entailing successful transfer. We show that such non-adultlike interpretations were present despite the children’s conceptual ability to entertain possible worlds. We propose that children may initially construct verb meanings on the basis of actual events, and later adjust them to include a modal component.
Must Realists Be Pessimists About Democracy? Responding to Epistemic and Oligarchic Challenges
Authors: Arlen Gordon , Rossi Enzo
Published: September 2020

In this paper we show how a realistic normative democratic theory can work within the constraints set by the most pessimistic empirical results about voting behaviour and elite capture of the policy process. After setting out the empirical evidence and discussing some extant responses by political theorists, we argue that the evidence produces a two-pronged challenge for democracy: an epistemic challenge concerning the quality and focus of decision-making and an oligarchic challenge concerning power concentration. To address the challenges we then put forward three main normative claims, each of which is compatible with the evidence. We start with (1) a critique of the epistocratic position commonly thought to be supported by the evidence. We then introduce (2) a qualified critique of referenda and other forms of plebiscite, and (3) an outline of a tribune-based system of popular control over oligarchic influence on the policy process. Our discussion points towards a renewal of democracy in a plebeian but not plebiscitarian direction: Attention to the relative power of social classes matters more than formal dispersal of power through voting. We close with some methodological reflections about the compatibility between our normative claims and the realist program in political philosophy.
Homogeneous quantum cascade lasers operating as terahertz frequency combs over their entire operational regime
Authors: Di Gaspare Alessandra , Viti Leonardo , Beere Harvey E. , Ritchie David D. , Vitiello Miriam S.
Published: September 2020

We report a homogeneous quantum cascade laser (QCL) emitting at terahertz (THz) frequencies, with a total spectral emission of about 0.6 THz, centered around 3.3 THz, a current density dynamic range Jdr = 1.53, and a continuous wave output power of 7 mW. The analysis of the intermode beatnote unveils that the devised laser operates as an optical frequency comb (FC) synthesizer over the whole laser operational regime, with up to 36 optically active laser modes delivering ∼200 µW of optical power per optical mode, a power level unreached so far in any THz QCL FC. A stable and narrow single beatnote, reaching a minimum linewidth of about 500 Hz, is observed over a current density range of 240 A/cm2 and even across the negative differential resistance region. We further prove that the QCL FC can be injection locked with moderate radio frequency power at the intermode beatnote frequency, covering a locking range of 1.2 MHz. The demonstration of stable FC operation, in a QCL, over the full current density dynamic range, and without any external dispersion compensation mechanism, makes our proposed homogenous THz QCL an ideal tool for metrological applications requiring mode-hop electrical tunability and a tight control of the frequency and phase jitter.
Sine Topp-Leone-G family of distributions: Theory and applications
Authors: Al-Babtain Abdulhakim A. , Elbatal Ibrahim , Chesneau Christophe , Elgarhy Mohammed
Published: September 2020

Recent studies have highlighted the statistical relevance and applicability of trigonometric distributions for the modeling of various phenomena. This paper contributes to the subject by investigating a new trigonometric family of distributions defined from the alliance of the families known as sine-G and Topp-Leone generated (TL-G), inspiring the name of sine TL-G family. The characteristics of this new family are studied through analytical, graphical and numerical approaches. Stochastic ordering and equivalence results, determination of the mode(s), some expansions of distributional functions, expressions of the quantile function and moments and basics on order statistics are discussed. In addition, we emphasize the fact that the sine TL-G family is able to generate original, simple and pliant trigonometric models for statistical purposes, beyond the capacity of the former sine-G models and other top models of the literature. This fact is revealed with the special three-parameter sine TL-G model based on the inverse Lomax model, through an efficient parametric estimation and the adjustment of two data sets of interest.