The research of cumulative valuation of physico-chemical from Tondano Lake was conducted in to dry season on 2015. The purpose of the study was to analysis of water quality of the Lake such as Total Suspeded Solid (TSS), Total Disolved Solid (TDS), and Conductivity (DHL), as physical parameters, and also chemical parameters such as pH, Ca, Mg, K, SO4, Nitrogen Total, NH3, NO3, Phosfat Total, PO4, and Fe. These were done by taking water sample on 24 location.The data were analysed by multivariate analysis with soft ware statistic R versi 3.3.2, and Water quality analysis based on water quality criteria for water environment, and Decree of Government Republic Indonesian No.82 /2001 about water quality management and water pollution control.Result revealed that average and deviation standart of phyco-chemical parameters are TDS (mg/l) 192.0471 ± 94.1827, TSS (mg/l) 13.33 ± 4.8154 , DHL ( µmhos/cm) 317.833 ± 161.984, pH (6.8875 ± 0.2291), Ca (mg/l) 16.6667 ± 7.2284, Mg (mg/l) 14.7714 ± 0.3860, K (mg/l) 2.330 ± 0.4467, SO4 (mg/l) 5.685 ± 5.3366, Total Nitrogen (mg/l) 2.993 ± 5.3364, NH3 (mg/l) 0.2348 ± 0.8543, NO3 (mg/l) 5.3567 ± 7.0824, Total Phosfat (mg/l) 0.3333 ± 0.4821, PO4 (mg/l) 0.1130 ± 0.3315, Fe (mg/l) 0.11 ± 0.1901Principle Componen Analysis (PCA) with Eigen value (cumulative % of variance) 62.68 % explaining 10 parameter of physical chemistry water and 10 research location as reduction data from initial data. Cluster analysis with reduction data formed (1) The research location between Eris village and eceng gondok area, and fish Pond Eris village, the dominant variable were TDS, DHL, Nitrogen Total, and NH3. (2) The research location in fish Pond Toulimembet village, in front of eceng gondok Urongo village, in front of eceng gondok Paleloan village, and in front of eceng gondok Roong village, the dominant variable were SO4, pH, and Mg, (3) The research location between Kakas villages and eceng gondok area , Kaweng village and eceng gondok area, Kaweng village and eceng gondok area, Toulimembet village and eceng gondok area, and also fish Pond Kaima village, the dominant variable were TSS, Ca, dan K.Tondano Lake has level of productivity from medium to high, and it is good for fish culture and fishery activity, prossed for drinking water, agriculture, animal husbandry, industry, and water power.Keywords : Valuation, physical chemistry water, criteria Abstrak Penelitian tentang kumulatif kualitas fisik kimia air Danau Tondano telah dilakukan pada musim kemarau tahun 2015. Tujuan penelitian adalah (1) menganalisis kualitas air Danau Tondano yang meliputi TSS, TDS, DH sebagai faktor fisika perairan , dan faktor kimia yaitu derajat keasaman (pH), parameter fisika air danau yaitu Calsium, Magnesium, Kalium, Sulfat, Total nitrogen, Amoniak, Nitrat, Total Phosfat, Phosfat terlarut, dan Besi (Fe).Sampel air di ambil pada 24 titik pengambilan sampel di Danau Tondano. Pengambilan sampel air pada kedalaman 20 meter dilakukan pada 21 titik atau lokasi penelitian, titik pengambilan sampel pada kedalaman 5 meter, 10 meter, dan 20 meter.Data hasil penelitian dianalisis dengan menggunakan (1) Analisis multivariate dengan bantuan perangkat lunak statistic R versi R 3.3.2. (2) Analisis kulaitas air dengan menggunakan kriteria kualitas air bagi lingkungan perairan, dan Peraturan Pemerintah Republik Indonesia No. 81 Tahun 2001 tentang pengelolaan kualitas air dan pengendalian pencemaran air.Hasil analisis menunjukan konsentrasi rata-rata dan stadar deviasi TDS (mg/l) 192.0471 ± 94.1827, TSS (mg/l) 13.33 ± 4.8154 , DHL ( µmhos/cm) 317.833 ± 161.984, pH (6.8875 ± 0.2291), Ca (mg/l) 16.6667 ± 7.2284, Mg (mg/l) 14.7714 ± 0.3860, K (mg/l) 2.330 ± 0.4467, SO4 (mg/l) 5.685 ± 5.3366, Total Nitrogen (mg/l) 2.993 ± 5.3364, NH3 (mg/l) 0.2348 ± 0.8543, NO3 (mg/l) 5.3567 ± 7.0824, Total Phosfat (mg/l) 0.3333 ± 0.4821, PO4 (mg/l) 0.1130 ± 0.3315, Fe (mg/l) 0.11 ± 0.1901. Melalui Analisis Komponen Utama (AKU) diperoleh nilai Eigen 62.68 % yang mampu menerangkan varian indicator 10 variabel lingkungan dan 10 lokasi penelitian sebagai hasil reduksi data. Analisi kluster dari data reduksi membentuk 3 kluster yaitu Kluster I di lokasi penelitian belakang eceng gondok Eris dan budidaya ikan Eris dengan variabel dominan TDS, DHL, Total Nitrogen, dan amoniak. Kluster II di lokasi penelitian budidaya ikan Toulimembet, depan eceng gondok Urongo, depan gondok Paleloan, Depan eceng gondok Roong dengan variabel dominan SO4, pH, dan Magnesium. Kluster III di lokasi penelitian belakang eceng gondok Kakas, belakang eceng gondok Kaweng, belakang eceng gondok Toulimembet, dan budidaya ikan Kaima dengan variabel dominan TSS, Ca, dan K. Danau Tondano memiliki tingkat kesuburan perairan yang dikategorikan sedang sampai tinggi, dan layak bagi kegiatan perikanan, air danau dapat diolah menjadi air minum, keperluan pertanian, peternakan, perikanan, industri dan listrik tenaga air.Kata kunci: Penilaian, fisika kimia air, Kriteria
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