Browsing All Posts filed under »plants«

Getting the message across

October 8, 2018

Comments Off on Getting the message across

Since recreational boaters can unintentionally spread invasive aquatic species while transporting boats and equipment from one body of water to another, it’s important that management agencies communicate the need for boaters to clean, drain and dry their gear after use.  Researchers used a questionnaire-based approach to find out if the way the “clean, drain and […]

How the food web affects river restoration

October 8, 2018

Comments Off on How the food web affects river restoration

River restoration commonly  concentrates on improving habitat quality for threatened fish populations.  However, because stream fish are strongly influenced by food availability, competition and predation, a case can be made for also incorporating food web modelling into the restoration process.  A group of environmental scientists developed an ecosystem model and applied it to a river-floodplain […]

What drives regional differences in streamflow?

October 8, 2018

Comments Off on What drives regional differences in streamflow?

Typically, large-scale models of stream flow take into account the interaction between climate and vegetation (which determines evapotranspiration) and landscape features that dictate how non-evaporated water is diverted to soil, groundwater and overland flow.  However, there are often strong spatial variations in streamflow drivers, which can limit the usefulness of global models.  Researchers drew on […]

The magical diatom diet

July 5, 2018

Comments Off on The magical diatom diet

In forested headwater streams, detritus derived from decaying plant material is the primary source of energy driving the aquatic ecosystem, and most studies of such systems have focussed on the fate of leaf litter, the main resource.   However, because the food quality of detritus is extremely low it’s unclear how headwater streams support their  biological […]

How land plants control water plants

July 5, 2018

Comments Off on How land plants control water plants

While terrestrial ecosystems rely on rainfall infiltration for their water supply, streamside ecosystems rely on the accumulation of surface and subsurface runoff in the riparian zone and the channel network.  Rainfall that manages to percolate through the soil profile recharges aquifers, and these  sustain streamflow and riparian and aquatic ecosystems during dry periods.  Focussing on […]

How delayed is the flow-on effect?

July 5, 2018

Comments Off on How delayed is the flow-on effect?

It’s generally accepted that river flows have a major influence on the structure of stream communities, but what’s the lag time from river discharge to community expression?  This question is particularly relevant for headwater streams that are vulnerable to seasonal drying or the over-extraction of groundwater, where changes in flow often lead to successional changes […]

Triggers for algal blooms: peak temperatures aren’t always important

July 5, 2018

1

There are concerns that human impacts  on freshwater systems – particularly temperature increases linked to climate change and nutrient enrichment caused by run-off and pollution – are encouraging the spread of blue-green algae (cyanobacteria) capable of generating toxic blooms that threaten human and animal health.  One such case is the recent spread of Cylindrospermopsis raciborskii, […]