Estimation of radiation doses from (137)Cs to frogs in a wetland ecosystem

Currently, there is no established methodology to estimate radiation doses to non-human biota. Therefore, in this study, various dose models were used to estimate radiation doses to moor frogs (Rana arvalis) in a wetland ecosystem contaminated with (137)Cs. External dose estimations were based on activity concentrations of (137)Cs in soil and water, considering changes in habitat over a life-cycle. Internal doses were calculated from the activity concentrations of (137)Cs measured in moor frogs. Depending on the dose model used, the results varied substantially. External dose rates ranged from 21 to 160 mGy/y, and internal dose rates varied between 1 and 14 mGy/y. Maximum total dose rates to frogs were below the expected safe level for terrestrial populations, but close to the suggested critical dose rate for amphibians. The results show that realistic assumptions in dose models are particularly important at high levels of contamination.     

Environmental Duty of Care: From Ethical Principle Towards a Code of Practice for the Grazing Industry in Queensland (Australia)

Among the options of government for reducing negative environmental externalities from agriculture is the institution of a polluter statutory liability. An environmental duty of care imposes a statutory liability on agents who interact with the environment to avoid causing environmental harm. This paper documents environmental duty of care provisions governing landholders in Queensland, Australia, with specific reference to the 2007 Queensland State Rural Leasehold Land Strategy. The paper reports on a positive response by a group of leaseholders within the Northern Gulf Region in Queensland who developed a prototype environmental code of practice for grazing—a land use not previously covered by such an institution in Australia. The paper concludes that (1) a statutory environmental duty of care and specific forms of leasehold tenure are elements of an effective strategy for implementing an agricultural environmental ethics in north Australia’s rangelands and (2) a grazing industry code of practice is a practical and important tool for the grazing industry to safeguard its social licence to operate.