Development of Trigger Levels to Assess Catchment Disturbance on Stream Suspended Sediment Loads in the Magela Creek Catchment,Northern Territory,Australia

Trigger levels for fine suspended sediment (FSS) load in streams are required to identify rainfall-runoff events that have significantly elevated FSS loads, compared with expected background loads, as a result of catchment disturbance. Stream FSS load data collected in the mine-impacted Magela Creek catchment in the wet-dry tropics were used to derive water quality management trigger levels for two approaches – a Before-After-Control-Impact Paired difference design (BACIP) and a regression relationship between observed FSS load and corresponding event discharge characteristics. The results indicate that both the BACIP and regression relationship approaches behave similarly, with similar FSS load events elevated above trigger levels. Notwithstanding this, it is recommended that in order to reliably assess the location and magnitude of a catchment disturbance on FSS load, a combination of BACIP and regression relationship approaches must be adopted. In this study, an event with a FSS load above trigger levels associated with both BACIP and the regression relationship fitted for the downstream site is considered to be significantly elevated as a result of a disturbance within the mine-impacted region. While this technique cannot conclusively determine whether the cause of the disturbance is mine-related or natural (such as fire or bank erosion), it is an efficient statistical method of identifying events that warrant further investigation and management action, if required.     

L'expansion occidentale dans le Levant: Les Vénitiens á acre dans la seconde moitié du treiziéme siécle

This case-study is the first attempt to examine a commercial outpost in the Crusader Levant within the context of the commercial and colonial expansion of its mother-city and in direct relation to its particular features. The Venetian quarter in Acre in the second half of the thirteenth century provided the physical setting for the exercise of authority by the state and a solid base for the expansion of its dominion. The Venetian administration there implemented the strict regulation of commerce and shipping enacted in Venice in this period, including several rules stemming from the particular needs of Acre. Various families of settlers from Venice, nobles as well as popolani, can be traced for several generations; the grant of Venetian status to natives of the Latin kingdom of Jerusalem, Latins oriental Christians, and Jews, enlarged the size of the Venetian population in Acre. The fate of the refugees who escaped from the city in 1291 is the last topic to be examined.     

Anthropology in the world: Limits and unity (Respond to this article at http://www.therai.org.uk/at/debate)

This editorial anticipates the conference Anthropology in the World by reflecting upon the influence of anthropology, and its limits, arguing that it is only by knowing where these limits are that we can be sure where and how it can best be judged. It is too, a call for unity, suggesting that in seeking to influence the external world, anthropology should unite across its sub‐disciplines, and in doing so a mutually‐beneficial exchange of practice, ideas and methodology will emerge.