The characteristics of leachate and its probable risks on surface and groundwater pollution were investigated following the analysis of some chemical parameters of the leachate generated in Groundwater parameters, however, satisfy drinking water quality standard except, the concentration of NH 4 + -N (maximum 74.2 ppm) and K (maximum 25 ppm).

Microalgae are the most primitive plant-sized cellular organisms commonly known as phytoplankton. The habitat of its life is in waters or humid places. This organism is a primary producer of water that has any capability to photosynthesis like any other high-level plants. This study examines mathematically the optimal control of light intensity and liquid waste nutrition in microalgae growth. Growth liter is done by setting the intensity of light in the process of glucose formation and nutrition tofu liquid waste, tapioca, industry, and households as the additional nutrients of microalgae. The Pontryagin maximun principles is used to determine the optimal control solution. The solution is solved from the state and co-state equation that stationery evaluated using the indexed performance maks 𝐽[𝑢1 + 𝑢2 ] = ∫ 𝐺(𝑡) − 𝑡𝑓 𝑡0 𝑆(𝑡) − 1 2 𝑢1 (𝑡) 2 − 1 2 𝑢2 (𝑡) 2𝑑𝑡 with the stationer condition that gives the optimal control 𝑢1 ∗ = 𝛾2𝛼2𝑄𝐵 and 𝑢2 ∗ = −𝛾5𝜌1𝑆. The results shows that before the optimal control of light intensity and nutrition of liquid waste is applied, the concentration of microalgae biomass becomes 5.915 g / liter on the 20th day stayed at the 105th day. The lipid quota with an initial value of 0.6 g/liter will decrease to 0.2 g / liter at 4th day which is the equilibrium point. Optimal control of the regulation of light intensity of 2-9 klux and liquid waste nutrition provided a significant increase in the amount of microalgae biomass and lipid quota, with the regulation of light intensity of 2- 9 klux and tofu liquid waste nutrition which gave the largest increase in the amount of microalgae biomass and lipid quota

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b_widodo@matematika.its.ac.idAbstract. Talaga Lake is one of several lakes in Central Sulawesi that potentially to be managed in multi purposes scheme because of its characteristic. The scheme is addressed not only due to the lake maintenance because of its sediment but also due to the Algae farming for its biodiesel fuel. This paper governs a suspended sediment distribution model of Talaga lake. The model is derived from the two dimensional hydrodynamic shallow water equations of the mass and momentum conservation law of sediment transport. An order reduction of the model gives six equations of hyperbolic systems of the depth, two dimension directional velocities and sediment concentration while the bed elevation as the second order of turbulent diffusion and dispersion are neglected. The system is discreted and linearized such that could be solved numerically by box-Keller method for some initial and boundary condition. The solutions shows that the downstream velocity is play a role in transversal direction of stream function flow. The downstream accumulated sediment indicate that the suspended sediment and its changing should be controlled by optimizing the downstream velocity and transversal suspended sediment changing due to the ideal algae growth need.

Salinity is a tracer of water and nutrient flows and is employed in studies on coastal environment to establish the coastal or remote origins of pollutants and nutrients. The present article analyses the effects of salinity on the multivariate distribution of the Trophic Index TRIX. The approach taken is based on a multivariate nested model with salinity as an explicative variable. We believe that our results are of use in discerning those areas of the North-West Adriatic Sea influenced by the Po River.