TY - JOUR TI - Evaluation of a gradient sampling design for environmental impact assessment AU - Ellis, J AU - Schneider, D T2 - Environmental Monitoring and Assessment AB - Before-After Control Impact (BACI) sampling designs are commonly used in environmental impact assessment and are considered the most effective for detecting changes due to anthropogenic disturbances. These designs handle local spatial variability through randomized placement of samples into a treatment stratum and a control stratum. When a contaminant disperses with distance from a point source it is suggested that a ’gradient‘ design will be more sensitive to change than randomized placement of samples. This requires allocating samples according to distance, rather than by random placement within randomly placed blocks. In this paper gradient versus random sampling designs were compared using data from an oil field in the North Sea. The gradient sampling design was more powerful than a randomized CI sampling design. DA - 1997/11// PY - 1997 VL - 48 SP - 157–172 UR - https://link.springer.com/article/10.1023%2FA%3A1005752603707 DO - 10.1023/A:1005752603707 LA - English KW - Chemicals KW - Physical Environment KW - Water Quality ER -