Today Environmental Impact Assessment (EIA) is known as one of the most important tools for decision makers in the construction of civil and industrial projects towards sustainable development. In the past, projects were evaluated based on cost and benefit analysis regardless of the physical and biological environmental effects and its socio-economical impacts. According to the Department of En...

Despite the fact that little is known about the consequences of hydropower production in tropical areas, many large dams (> 15 m high) are currently under construction or consideration in the tropics. We researched the effects of large hydroelectric dams on aquatic macroinvertebrate assemblages in two Costa Rican rivers. We measured physicochemical characteristics and sampled aquatic macroinver...

T he advantages of using a rubber dam are well-known when performing operative and endodontic procedures. These benefits include the following: disolation of the operating field to keep it dry and clean; dimproved access and visibility; dpotentially improved properties of dental materials; dprotection of the patient and dentist; dimproved operating efficiency. 1 Preparing teeth for indirect res...

development throughout the world for thousands of years, providing water, controlling floods, irrigating crops, facilitating navigation, creating recreational opportunities, and generating motive power and electricity. By the end of the 20th century, about 45 000 large dams (>15 m in height) and an estimated 800 000 small dams had been built worldwide (WCD 2000), obstructing over 65% of fresh w...

Beaver have been referred to as ecosystem engineers because of the large impacts their dam building activities have on the landscape; however, the benefits they may provide to fluvial fish species has been debated. We conducted a watershed-scale experiment to test how increasing beaver dam and colony persistence in a highly degraded incised stream affects the freshwater production of steelhead ...

Background: Strong earthquakes are among the prime triggering factors of landslides, which may block rivers, forming landslide dams. Some of these dams may pose serious threats to people and property due to upstream inundation and downstream dam-breach flooding. Evaluating the stability and potential hazard of landslide dams is significant for the mitigation measures, but remains challenging. T...

Recently the design flows of many dams have been re-evaluated, resulting in spills often larger than the original ones. In many cases, occurrence of revised flows would result in dam overtopping because of insufficient storage and spillway capacity of reservoirs. Embankment dams whilst common are more likely to fail than other dam types when overtopped in an uncontrolled manner because of breac...

BACKGROUND The Pak-Mun dam is a controversial hydro-power project on the Mun River in Northeast Thailand. The dam is sited in a habitat of the freshwater snail Neotricula aperta, which is the intermediate host for the parasitic blood-fluke Schistosoma mekongi causing Mekong schistosomiasis in humans in Cambodia and Laos. Few data are available which can be used to assess the effects of water re...