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Aims Microbial induced calcium carbonate precipitation (MICP) is one of the bio‐cementation methods for improving granular soils. This study evaluate the feasibility of obtaining a bacterial solution with high optical density and urease activity by an inexpensive corn steep liquor (CSL) medium in non‐sterile conditions in order to achieve sand improvement. Methods and Results Corn steep liquor media with different concentrations (different dilution rates) were prepared and, without any autoclaving (non‐sterile conditions), different percentage of the inoculum solutions were added to them and incubated. Effect of inoculum solution percentage and CSL dilution rates on specifications of bacterial solution was evaluated. Urease activity and scanning electron microscope (SEM) and X‐Ray Diffraction (XRD) were used to efficiency of CLS media in sand improvement. The considerable urease activity was measured as 5·7 mS cm−1 min−1 using nonsterile CLS. By using CYNU (CSL‐Yeast extract‐NH4Cl‐Urea) bacterial solution, the urease activity of 5·5 mS cm−1 min−1 for the OD600 (optical density at 600 nm) of 1·88 and, consequently, specific urease activity of 2·93 mS cm−1 min−1 OD600−1 was obtained. The highest unconfined compressive strength (811 kPa) was obtained for the CYNU. XRD revealed new calcite peaks next to the quartz peaks. Conclusions Production of inexpensive bacterial solution using diluted CSL as the inexpensive, effective and powerful culture media for Sporosarcina pasteurii cultivation in nonsterile conditions, allows geotechnical and biotechnological engineers to use MICP technology more widely in land improvement and field‐scale bio‐cementation and bioremediation projects. Significance and Impact of the Study Obtaining high urease activity of inexpensive microbial solution using diluted CSL as the culture medium in nonsterile conditions, as the unique results of this study, can be significant in the field of bioremediation studies using MICP.

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Development after the 2004 tsunami in Aceh province included the relocation of housing to disaster-safe areas, and the community can continue their lives, especially in the northern and western coastal regions of Aceh. A few years after the tsunami that damaged the beach, there was a change in the physiography of the coast (growing land), so that people returned to their original activities. This paper aims to describe the changes in the management of the area and patterns of community living that adapt to changes in coastal physiography in a sustainable manner. This discussion is essential, related to the new knowledge needed as a reference for post-disaster settlement development so that the synergy between national policies and local wisdom. The Approach of the studies is interpretative phenomenological research with case studies in Gampong Saney, Lhoong sub-district, Aceh Besar District. The research method is in the form of qualitative inquiry by describing the symptoms of residence (location of housing, place of livelihood activities) and interpreting it on aspects of community life, the natural environment, and regional development factors. The results showed that relocation housing was located on a dynamic, ecologically developed hill. Regional infrastructure development has a perspective on local disaster and wisdom. Society is more sensitive to natural changes and seeks to empower. The old life is slowly reawakening to adjust to the current conditions. The observation concludes that there is a change in the pattern of settlement space, which is oriented back to the sea, and economic activity becomes more diverse between land and sea. Disasters that change the coast’s physiographic have increased the diversity of natural resources and made more effectiveness to village spatial arrangements that improve the sustainability system of community life.

Fish scale gelatin as an alternative to pork gelatin is largely demanded by the community. The gelatin can be used as a stabilizer in the production of ice cream. This study aimed to define the potential of milkfish scale gelatin (Chanos chanos) as a stabilizer in ice cream. The milkfish scale gelatin with different concentrations used in this research were 0% as control, 0.3%, 0.5%, and 0.7%. Samples were analyzed such as yield, gel strength, and viscosity of gelatin as well as protein, overrun, melting rate, and hedonic tests on ice cream with three times of 100 replications. This study revealed that the addition of various concentrations of gelatin had a significant effect on the test parameters (p<0.05) in ice cream. The results of the gelatin yield test were 9%, the gel strength was 134.32 blooms, and the viscosity was 3.01 cP. The results of milkfish scale gelatin ice cream with three replications at a concentration of 0.7% overall had a better value, which concluded that milkfish scale gelatin has the potential to be used as an ice cream stabilizer and was well accepted by the panelis.

Background. In this research, the potential of the microbially induced carbonate precipitation method for the surface treatment of sand samples of Jabal Kandi dunes, located in the adjacency of Urmia Lake in the northwest of Iran, was considered. Methods. Sporosarcina pasteurii was used as ureolytic bacteria for the preparation of the microbial solution. Corn steep liquor containing urea was used as an inexpensive growth media. The effects of the concentration of cementation solution and the number of treatment cycles were considered. Because of the presence of some hydrolyzed urea in the prepared microbial suspension, two methods of treatment, i.e., the mixed and separate addition of microbial solution and cementation solution to the sand surface, were investigated. Penetration and erosion resistance of the microbial treated sand (sand crust) were measured using a handheld penetrometer and a wind tunnel system. Results. The results showed that the penetration and erosion resistance of the treated sand samples via microbial-induced carbonate precipitation method were improved significantly. In the method with the separate addition of microbial and cementation solutions to the sand surface, a stable sand crust was created on top of the sand. Discussion. This study tried to optimize the microbial application of Sporosarcina pasteurii for surface treatment of sand via microbial-induced carbonate precipitation. Significant and results showed that this method can be used on the field scale for the stabilization of sand dunes. The advanced biotechnology application of this bacterium can be used as an environmentally friendly and safe method instead of other methods.

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Variation in groundwater with excessive withdrawal is one of the causes of land subsidence. Withdrawal of groundwater level can cause an increase in effective stress at thick clay layers, leading to land subsidence. In Rafsanjan plain in Iran, due to the excessive use of groundwater, land subsidence has caused earth fissures and damages to the buildings and installations. Variation in water table level may happen due to the seasonal extraction of groundwater in spring and summer for farming and replacement due to rainfall in fall and winter. The behavior of soils due to the rise of ground water table is non-linear; therefore, a part of settlements may not be recoverable and therefore, it must be considered in the analysis. Modeling of this phenomenon and formulation was considered by finite element method in this research. Finite Element method was used based on element equilibrium and fluid continuity equations. The nonlinear behavior of soil was applied by the bilinear model. The rate of settlements and variation in pore pressure caused by the oscillation of groundwater table were determined by using this model. A good correlation was observed between the results of finite element model and actual data in Rafsanjan area in Kerman Province.