Browsing All Posts filed under »habitat diversity«

Dealing with river complexity

March 27, 2017

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Hydromorphology is a relatively new field that deals with the structure of hydrological systems and changes in their form over time. Many such changes are influenced by human-induced pressures. Realistic attempts to conceptualize hydromorphological forms and processes reflect the fact that rivers are complex multidimensional systems with longitudinal, lateral, vertical and temporal components, as well […]

Tree cover makes for lower fish diversity

March 27, 2017

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A pervasive feature of lowland streams, especially in areas where land has been cleared for agriculture or urban development, is a decrease in forested cover from the headwaters to the mouth. The presence or absence of streamside tree cover has a profound influence on stream ecology. Streams running through undisturbed forests typically contain large woody […]

How river transport affects dissolved organic matter

December 13, 2016

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In most rivers, the downstream transport of dissolved organic matter (DOM) makes large amounts of energy available to aquatic ecosystems. The River Continuum Concept (RCC) of Vannote et al. (1980) provided a useful framework for studying the influence of organic material from headwater streams on the structure and function of downstream ecosystems. The RCC hypothesized […]

Deciding on sites for conservation

December 13, 2016

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Biodiversity conservation is hampered by the fact that many species haven’t been described and most species ranges haven’t been mapped. As a result, in selecting sites for protection, natural resource managers often resort to the use of surrogate indicators for the species that they wish to conserve. Surrogates may be other, more common, species, or […]

Restoration ecology: are we forgetting top-down control?

June 1, 2016

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Authors of a recent review article argue that restoration ecologists rely heavily on the assumption that natural communities are controlled by bottom-up processes (i.e., the upward transfer of nutrients and energy from plants to animals), but tend to ignore the complementary effects of top-down control by animals on nutrient cycling and the abundance and diversity […]

Advantages of rough wetland designs

June 1, 2016

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In natural wetlands, the unevenness of the ground creates variation in environmental factors such as soil moisture and temperature, and this variability is a positive influence on the range of plant species that are able to colonise the area. As they become established, plants such as sedges and rushes slowly create tussocks, which further increase […]

The dynamics of habitat choice: alien predators stifle amphibian breeding

June 1, 2016

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The way that animals select habitats reflects their need to balance the costs and benefits associated with factors such as food availability and predation risk. Therefore, habitat choices should vary in response to changes in these key factors. As an example, amphibians are expected to continually adjust the relative amounts of time that they spend […]