A river-ecosystem is strongly affected by human activities. The pollutants discharged into a river from human activities may destroy the ecosystem of the river. Microorganisms in rivers (including suspended and sessile microorganisms) play key roles in degrading the pollutant and therefore in preventing the river ecosystem from being destroyed. To establish suitable measures for the protection ...

As “kidneys of the earth”, wetlands play an important role in ameliorating weather conditions, flood storage, and the control and reduction of environmental pollution. With the development of local economies, the wetlands in both the Amazon and Yangtze River Basins have been affected and threatened by human activities, such as urban expansion, reclamation of land from lakes, land degradation, a...

The annual migration of ∼1.2 million wildebeest (Connochaetes taurinus) through the Serengeti Mara Ecosystem is the largest remaining overland migration in the world. One of the most iconic portions of their migration is crossing of the Mara River, during which thousands drown annually. These mass drownings have been noted, but their frequency, size, and impact on aquatic ecosystems have not be...

The shrinking Baiyangdian Lake and drying up rivers are widely observed in recent years. Due to the significant advantages in integrated analyses of natural and economic systems, emergy analysis is introduced in this paper to assess the health status of Baiyangdian Watershed. First, we establish a emergy based conceptual framework for the assessment, delineate an emergy flow diagram of Baiyangd...

Assessing and quantifying ecosystem vulnerability is a key issue in site-specific ecotoxicological risk assessment. In this paper, the concept of vulnerability, particularly referred to aquatic ecosystems is defined. Sensitivity to stressors, susceptibility for exposure and recovery capability are described as component of vulnerability of biological communities. The potential for habitat chang...

We introduce the river wave concept: a simple, holistic model that unifies river ecosystem concepts. The river wave concept proposes that river flow can be conceptualized as a series of waves varying in shape, amplitude, wavelength, and frequency, traveling longitudinally and laterally; the position on the wave determines the source of organic production or inputs and the storage, transformatio...

The ecosystem health of rivers downstream of dams is among the issues that has become focus of attention of many researchers particularly in the recent years. This paper aims to deal with the question, how the environmental health of a river ecosystem can be addressed in water resources planning and management studies. In this study, different parameters affecting the ecosystem of river-reservo...

River channels and their flood plains are among the most naturally dynamic ecosystems on earth, in large part due to periodic flooding. The components of a river's natural flood regime (magnitude, frequency, duration and timing of peak flows) interact to maintain great habitat heterogeneity and to promote high species diversity and ecosystem productivity. Flood regimes vary within and among riv...