The Depositional Influence in Regard of Environment Carrying Capacity in Waters at Inner Ambon Bay to Floating Net Cage Propagate

Abstract

Inner Ambon bay is a shallow and narrow waters that serve as the location of floating net aquaculture systems, but its water quality is threatened by depositional. This research is aimed at knowing depositional rate, its effect to carrying capacity of marine environment that indicated by water quality, and to formulate environmental management strategies. Depositional rate assessed by calculating the rate of suspension sediment discharge from river, potential erosion estimates with USLE method, satellite imagery analysis of year 2004 and 2012, rate of water flow analysis from outer Ambon bay to inner Ambon bay, as well as bathymetric data analysis of year 2008 and 2012. To determine the water quality, sampling and laboratory test as well as scoring, weighting and matching was did to parameters, that is turbidity, DO, pH, brightness, temperature, TSS, TDS, gross primer productivity and nett primer productivity, while its environmental management strategies studied by causal approach. The research finding showed that depositional rate from suspension sediment discharge calculation and unit convertion of Wae Heru river and Wae Tonahitu river is 1.7 cm/year, while the class of potential erosion at the Wae Heru and Wae Tonahitu river mouth, both of them is very light (<15 tons/hectare/year). Satellite imagery analysis showed that depositional rate at Wae Heru and Wae Tonahitu mouth river is 2445 square meters/year and 1459.625 square meters/year respectively. Through complementary data, that is the rate of water flow analysis obtained that rate of water flow to inner Ambon bay is 84 cm/s, whereas bathymetric analysis show a reduction in water depth is 13.9 cm/year. Results of water quality analysis indicates that the carrying capacity of waters are in the medium class, as well as refer to depositional rate and water quality, so environmental management strategy is focused on the management of upstream rivers, midstream rivers, downstream rivers, riparian and coastal area.

Kecenderungan Perkembangan Kota Ambon: Dampaknya Terhadap Kualitas Lingkungan Pesisir Teluk Ambon Dan Kerentanannya Terhadap Bahaya Terkait Dengan Kenaikan Muka Laut

“…Di depan telah disebutkan bahwa perluasan Kota Ambon terjadi ke arah perbukitan. Pengembangan kota tersebut dilakukan dengan mengkonversi kawasan hutan di daerah perbukitan menjadi daerah pemukiman (Barkey et al, 2017;Kakisina et al, 2015;Saiya et al, 2014). Efek dari kegiatan konversi tersebut adalah meningkatnya erosi di perbukitan dan berujung pada meningkatnya suplai muatan sedimen ke perairan Teluk Ambon (Rahmawan et al, 2019;Kakisina et al, 2015;Saiya et al, 2014).…”

“…Pengembangan kota tersebut dilakukan dengan mengkonversi kawasan hutan di daerah perbukitan menjadi daerah pemukiman (Barkey et al, 2017;Kakisina et al, 2015;Saiya et al, 2014). Efek dari kegiatan konversi tersebut adalah meningkatnya erosi di perbukitan dan berujung pada meningkatnya suplai muatan sedimen ke perairan Teluk Ambon (Rahmawan et al, 2019;Kakisina et al, 2015;Saiya et al, 2014). Suplai muatan sedimen yang tinggi terutama terjadi pada musim hujan yang membuat air laut perairan Teluk Ambon berubah warna menjadi coklat kemerahan karena tingginya kandungan muatan suspensi (Saiya et al, 2014;Wouthuyzen, 2001).…”

“…Efek dari kegiatan konversi tersebut adalah meningkatnya erosi di perbukitan dan berujung pada meningkatnya suplai muatan sedimen ke perairan Teluk Ambon (Rahmawan et al, 2019;Kakisina et al, 2015;Saiya et al, 2014). Suplai muatan sedimen yang tinggi terutama terjadi pada musim hujan yang membuat air laut perairan Teluk Ambon berubah warna menjadi coklat kemerahan karena tingginya kandungan muatan suspensi (Saiya et al, 2014;Wouthuyzen, 2001). Keadaan tersebut terjadi di Teluk Ambon Dalam dan Teluk Ambon Luar.…”

“…Perairan Teluk Ambon mengalami penurunan kualitas dalam bentuk meningkatnya kekeruhan karena meningkatan muatan suspensi. Hal itu terjadi sangat jelas di musim hujan (Saiya et al, 2014;Wouthuyzen, 2001).…”