Penelitian ini bertujuan untuk menganalisis efektivitas serat jerami padi sebagai lapisan penutup permukaan tanah dalam kendali erosi lereng. Penelitian ini dilakukan dengan 3 variasi intensitas hujan 50 mm/jam, 100 mm/jam, 120 mm/jam. Hasil penelitian ini menunjukkan efektivitas serat jerami padi pada lapisan penutup dengan persentase 30% tereduksi jika dibandingkan tanpa lapisan penutup. Besarnya laju erosi persentase 30% atau berat kering 38,7 gr/m 2 rata-rata sebesar 17,068%. Dengan kata lain, laju erosi tanpa lapisan penutup tereduksi ratarata sebesar 82,932%. Demikian pula efektivitas serat jerami padi dengan persentase 60% dan 90% atau berat kering145,1 gr/m 2 dan 354,8 gr/m 2 juga tereduksi jika dibandingkan tanpa lapisan penutup. Besarnya laju erosi pada persentase 60% rata-rata sebesar 7,216% dan persentase 90% rata-rata sebesar 4,392%. Dengan kata lain, laju erosi tanpa lapisan penutup tereduksi rata-rata sebesar 92,784% persentase 60% dan rata-rata 95,608% persentase 90%.

The study aims to determine the suitable location of biopore infiltration holes by utilizing Geographic Information Systems Software (GIS) in adopting appropriate technologies Biopore Infiltration Hole (LRB) at inundation areas in the eastern city of Makassar. The analysis of this study is conducted in the form of qualitative analysis which to identify the type of soil in the research and as well as quantitative analysis to determine the suitable location applied in Biopore Infiltration Hole (LRB). In the outline, the concept of applying the analysis technique of superimpose with the three variables of determining analysis location of Biopore Infiltration Hole (LRB) such as soil type, rainfall and built coefficient region. The results of this study indicate that the three sites are suitable to be applied Biopore Infiltration Hole (LRB), namely; location IV (RT 3 RW 6 Berua), location V (RW 7 Mangga Tiga) and the location VI (RW 16 Blok Ae BTP) in Paccerakkang village which each location requires a number of absorption biopore holes as much as 84,417 for IV location, 6,894-6,644 locations V and VI for the location.The utilization of GIS Software in implementing Biopore Infiltration Hole (LRB) obtained a map view location which is suitable to be applied for biopore hole absorptions and the number of needs in the region.

For the first time, this experimental research analyzed the efficacy of rice straw fiber as soil cover in controlling slope erosion using a physical model. Three variations of rainfall intensity, soil slope degree, and rice straw fiber were conducted in this research. The results showed that rice straw fiber in the physical model had reduced the amount of erosion significantly. In general, a higher erosion rate was obtained with the increases of rainfall intensity and soil slope degree. The experiment was conducted with the percentage 30%, 60%, and 90% of soil cover using rice fiber straw, reducing erosion rates by 92.09%, 95.55%, and 98.21 %, respectively. Therefore, the higher the percentage of rice straw fiber used as soil cover, the smaller the ground will be affected by erosion. The ratio from the soil affected by erosion was 7.91%, 4.45%, and 1.79%, respectively. The result reveals that there is a significant decrease in erosion due to the increase of fiber used in the experiments. Meanwhile, the amount of erosion in the physical model without soil cover was 98.21% for the same rainfall severity and soil slope degree. This research showed that the application of rice straw fiber as a soil surface shield is highly effective in controlling slope erosion.

This paper assesses the extent of saltwater intrusion (SWI) in coastal aquifers in two sub-districts of Jeneponto Regency, Indonesia, for the first time using an analytical method in the form of a sharp-interface approach and numerical dispersive simulation of a finite difference solution developed by SEAWAT, based on field observations and secondary field data. In general, the SWI extents obtained from the analytical solutions for four aquifers in the region are around 30% greater than numerical solutions. The results show that the maximum SWI extent occurs in the Binamu2 aquifer in Jeneponto Regency, where the analytical solution and numerical simulation produced SWI extents of 850.4 m and 510, respectively. The higher results in the sharp interface model compared to the numerical model are most likely due to the pushing seaward effect caused by the presence of circulating flow inside the saltwater wedge below the freshwater-saltwater interface, which is considered in the numerical solution but not in the analytical solution, as explained in the previous SWI study. The results also revealed that the SWI conditions in Jeneponto Regency are still within reasonable limits, but groundwater exploitation control is critical in the region to maintain this situation.

This study aims to analyze the distribution of floods in the Bila River and its countermeasures in reducing the impact that occurred in Sidrap Regency. The study performs hydrological analysis using the Bila watershed rainfall data, calculates the planned flood discharge using the HSS SCS model, and simulates the flood flow profile using the HEC-RAS 2D numerical model. It is found that the Q20 flood discharge of the Bila and the Bulucenrana Rivers entered the Bila River downstream calculated from the HSS SCS analysis are 738.60 and 779.50 m3/s, respectively. The overflow of the Bila River flood affects 9 villages, namely Kalola Village (0.06 km2), Sogi Village (0.01 km2), Kalosi Alau Village (0.32 km2), Kampale Village (0.11 km2), Salomalori Village (0.42 km2), Tanru Tedong Village (2.12 km2), Kalosi Village (0.91 km2), Salobukkang Village (1.70 km2), and Taccimpo Village (4.01 km2). It is proposed that the best solution to deal with the issue is by introducing an eco-drainage system, namely by constructing a retention pond with a maximum storage volume of 3.81 million m3 or with a normal storage of 2.4 million m3. The existence of a retention pond can reduce the inundated area around 8.28 km2 or 85.71%.