Electronic Theses and Dissertation

Ketersediaan air irigasi yang memadai menjadi faktor penting dalam mendukung pertumbuhan tanaman dan keberhasilan produksi pertanian. namun, pada kondisi tertentu ketersediaan air dari sumber irigasi utama dapat menurun, sehingga diperlukan sumber air alternatif yang tetap memenuhi persyaratan kualitas, salah satunya air saluran drainase pertanian. meskipun demikian, air drainase berpotensi membawa zat terlarut dari aktivitas pertanian sehingga perlu dievaluasi kualitasnya sebelum dimanfaatkan. penelitian ini bertujuan mengevaluasi status kualitas air pada saluran drainase bakoy, kecamatan ingin jaya, kabupaten aceh besar, serta menilai kelayakannya sebagai sumber air irigasi alternatif berdasarkan parameter ssp dan sar. penelitian menggunakan metode survei dengan pengambilan sampel secara purposive pada tiga titik pengamatan (hulu, tengah, hilir) dan dua fase pertumbuhan padi (vegetatif dan panen), untuk mengetahui perubahan kualitas air secara spasial dan temporal. kandungan ion na²⁺, ca²⁺, mg²⁺, dan k⁺ dianalisis di laboratorium baristand aceh menggunakan metode icp-oes, sedangkan ph, daya hantar listrik (dhl), dan total dissolved solids (tds) diukur secara in situ. nilai ssp dan sar kemudian dihitung dan dibandingkan dengan klasifikasi kualitas air irigasi menurut wilcox (1955) dan fao (1985). hasil penelitian menunjukkan bahwa nilai ph berkisar antara 7,75–8,62, dhl sebesar 0,286–0,436 μmhos/cm, dan tds sebesar 143–218 mg/l, seluruhnya tergolong sangat baik hingga baik menurut standar fao (1985). nilai ssp pada fase vegetatif berkisar 29,9–34,8% dan pada fase panen 25,8–35,7%, seluruhnya tergolong baik menurut klasifikasi wilcox (1955) karena masih di bawah ambang batas 50%. sementara itu, nilai sar pada fase vegetatif berkisar 0,6206–0,8775 meq/l dan pada fase panen 0,2682–0,4024 meq/l, seluruhnya tergolong sangat baik menurut fao (1985) karena jauh di bawah ambang batas 10 meq/l. hasil tersebut menunjukkan bahwa kualitas air saluran drainase di desa bakoy memenuhi kriteria sebagai sumber air irigasi alternatif berdasarkan parameter fisik dan kimia yang dianalisis. kata kunci: kualitas air, saluran drainase, ssp, sar, air irigasi alternatif

Adequate irrigation water availability is an important factor in supporting plant growth and successful agricultural production. However, under certain conditions the availability of water from the main irrigation source may decline, requiring an alternative source that still meets quality requirements — one such source being agricultural drainage water. Nevertheless, drainage water may carry dissolved substances from agricultural activities, so its quality needs to be evaluated before use. This study aimed to evaluate the water quality status of the Bakoy Drainage Channel, Ingin Jaya Subdistrict, Aceh Besar Regency, and to assess its feasibility as an alternative irrigation water source based on the SSP and SAR parameters. The study used a survey method with purposive sampling at three observation points (upstream, middle, downstream) across two rice growth phases (vegetative and harvest), to determine spatial and temporal changes in water quality. Na²⁺, Ca²⁺, Mg²⁺, and K⁺ ion concentrations were analyzed at the BARISTAND Aceh Laboratory using the ICP-OES method, while pH, Electrical Conductivity (EC), and Total Dissolved Solids (TDS) were measured in situ. SSP and SAR values were then calculated and compared with the irrigation water quality classifications of Wilcox (1955) and FAO (1985). The results showed that pH values ranged from 7.75–8.62, EC ranged from 0.286–0.436 μmhos/cm, and TDS ranged from 143–218 mg/L, all falling within the very good to good category based on FAO (1985) standards. SSP values in the vegetative phase ranged from 29.9–34.8% and in the harvest phase from 25.8–35.7%, all classified as good according to Wilcox (1955), remaining below the 50% threshold. Meanwhile, SAR values in the vegetative phase ranged from 0.6206–0.8775 meq/L and in the harvest phase from 0.2682–0.4024 meq/L, all falling into the very good category based on FAO (1985), being well below the 10 meq/L threshold. These results indicate that the drainage channel water quality in Bakoy Village meets the criteria as an alternative irrigation water source based on the physical and chemical parameters analyzed. Keywords: water quality, drainage channel, SSP, SAR, alternative irrigation water