Development and application of GIS-based multi-model system for risk assessment of geological hazards

Transgenic plants that produce pesticidal proteins will release these proteins into the soil when these plants are incorporated into the soil by tillage or as leaf litter. Little is known about the fate and persistence of transgenic plant pesticidal products in the soil. We used a model system of transgenic cotton that produces Bacillus thuringlensis var. kurstaki δ-endotoxin (Btk toxin) to evaluate the persistence of transgenic pesticides in soil. Purified Btk toxin or transgenic cotton leaves containing Btk toxin were added to soil in five different microcosm experiments in concentrations ranging from 1 to 1600 ng Btk toxin/g soil. The concentration of the extractable Btk toxin was measured for up to 140 days. An initial rapid decline in extractable toxin concentration in the first 14 days, followed by a slower decline, was observed in four of the five experiments. At the end of the experiments, Btk toxin from transgenic plant tissue was undetectable (less than 0.1% of starting concentration) in two of the microcosm experiments and at 3, 16, and 35% of the original amounts in the other experiments. In addition, experiments using γ-irradiated sterilized soil indicated that the observed decline in extractable toxin concentration was due largely to biotic degradation rather than to physical adsorption by the soil.Key words: transgenic plants, Bacillus thuringlensis toxin, risk assessment.

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Risk Assessment of Geological Hazards in a Tunneling Project Using Harmony Search Algorithm (Case Study: Ardabil-Mianeh Railway Tunnel)

Civil Engineering Journal ◽

10.28991/cej-2016-00000057 ◽

2016 ◽

Vol 2 (10) ◽

pp. 546-554 ◽

Cited By ~ 7

Author(s):

Reza Mikaeil ◽

Sina Shaffiee Haghshenas ◽

Yakob Shirvand ◽

Mehdi Valizadeh Hasanluy ◽

Vali Roshanaei

Keyword(s):

Risk Assessment ◽

Search Algorithm ◽

Harmony Search ◽

Harmony Search Algorithm ◽

Water Inflow ◽

Geological Hazards ◽

Railway Tunnel ◽

Accuracy Of Results ◽

Tunnel Instability

During the design and implementation of underground constructions, the risk assessment and management of geological hazards are important due to the hazards such as the water inflow, collision with crushed fault zones, squeezing and instability around excavation zones. In the present research, it is attempted to study and assess the risk of geological hazards in 378+021 km of the route of Ardabil-Mianeh railway tunnel using the harmony search algorithm (HSA). In the first section of research, after studying structural and geological characteristics during 24 sections of the excavation route, the risk relating to geological hazards including the tunnel instability, squeezing, water inflow and swelling was assessed in three separate classes using HSA. In order to study the accuracy of results, geological hazards recorded during the implementation of excavation operations were used. Studies obtained from the comparison of observed and predicted results indicate the high accuracy of HSA in the assessment and prediction of geological risks in the tunnelling project.

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