Changes in the condition of aquatic environment are now a major problem for the survival of every organism caused by changes in land use, human activities, and agriculture. This study aims to determine the structure of macroinvertebrate communities. In addition, this study also aims to conduct analysis on BMWP index and water quality testing using physical and chemical parameters. This study was conducted on tertiary channels in Songka Sub-District, Palopo City. Each station's data collection covered relative density, macroinvertebrates that were found were assessed using BMWP index, then they were calculated using ASPT index. The results of this study found 17 taxa classified in the class of gastropods, insecta, bivalvia, malacostraca, citellata, oligochaeta and hirudenia. The results of BMWP index modification analysis from all stations found that ASPT value was "quite-poor" and "bad". It was indicated that in each station was mainly dominated by Oligochaeta worms and tolerant macroinvertebrates. Testing of physical and chemical parameters obtained DO value which belonged to class II of water quality. The low DO value caused high BOD value, which was classified in class III. The high value of BOD had an effect on the rise of COD value, the increase of COD value was caused by the high amount of organic and inorganic materials entering the water. PH value was relatively normal with the range of 6.3 to 6.8, temperature was in the range of 27.1°C to 28°C, the rise in temperature value was influenced by tree shade and the intensity of sunlight.

Research has been carried out on the manufacture of tungsten indicator electrodes with a diameter of 1 mm coated with PVA-Enzyme coated with PVC-KTpClPB using the biosensor potentiometer method. It has a sensitivity of 19,096 mV/decade, a detection range of 1.10-5 - 5.10-4 M, a detection limit of 1.10-5 M and a correlation coefficient of R2 = 0.9431. This detection range is very small, only a difference of one order to the negative power. On the basis of this small range, the PVA-Enzyme and PVA-Enzyme-GA solutions have been characterized by UV-vis showing a very clear difference in the width of the absorbance peak at wavelength. The indicator electrodes B1-4 and B3-4 have been analyzed using UV-vis, FTIR, SEM-eds and XRD. The method used is the biosensor poteniometric method, urease enzyme immobilization technique, which analytes urea in determining sensitivity, detection range and detection limit, as well as variable signal analysis of 60 signals/second. The results obtained from the indicator electrode B1-4 have a sensitivity of 46.67 mV/decade, a detection range of 10-4 - 10-2 M and a detection limit of 10-4 M, R2 = 99.62 %. The indicator electrode B3-4 has a sensitivity of 38.16 mV/decade, a detection range of 10-6 - 10-4 M and a detection limit of 10-6 M, R2 = 95.42 %. The best results on electrodes B1-4.

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Dye Sensitized Solar Cell (DSSC) has been made from ZnO-TiO2, activated carbon, electrolyte, ITO coatingHCl and Na2SO4. The process of making ZnO-TiO2 used the method sol gel. The results of the ZnO-TiOlayer2 with various dehydrolysis temperatures: 3000C, 5500C, 8000C, 10000C and 12500C, were characterized using X-Ray to determine the crystal size and peak wavelength. The results of X-Ray analysis on the ZnO-TiO layer have grain sizes ranging from (457.425; 45.74), (427.717; 42.77) and (374.419; 37.44) nm. The X-Ray The highest and lowest peaks were found at 800oC. The size of the Scanning Electron Microscopy (SEM) type EVO MA 10 was to determine the surface morphology. The results of SEM analysis on the ZnO-TiOlayer2 have grain sizes ranging from (35.325±4.701); (47.451 ± 13.242) and (51.541 ± 13.564) μm for each dihidrolisis temperature of 300 ° C, 550 ° C, 800 ° C, 1000oC and 1250oC. To determine the absorbance of the dye to a layer of ZnO-TiO2 used UV - VisSpectrophotometer RayLEIGH – UV-1601 and I-V brandmeter Keithley for DSSC current and voltage measurement. The UV-Vis Spectrophotometer results showed that the ZnO-TiOlayer2 successfully absorbed the solution dye in the visible light absorption area. The temperature change of the hydrolysis suggests that heating the ZnO-TiOlayer2 influences solar cell performance. The maximal efficiency at 800C is (7..1±0.025)x10-3 % using IV-a meter Keithley and (8.5±0.35)x10-3 % using a circuit. The result can provide a current of 1.9-4.5 mA and a maximum voltage of 3.7 - 8.5 eV.

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