Browsing All Posts filed under »plants«

Coarse, shallow and wooden… but useful nonetheless

June 19, 2017

0

Coarse woody debris (CWD) derived from shoreline trees provides an important, spatially complex habitat and a food source for lake-dwelling organisms. Here are some interesting facts about lake CWD, taken from a recent review paper: In the absence of the physical action of flowing water, CWD breaks down more slowly in lakes than in streams. […]

Plankton migration is system-dependent

June 19, 2017

0

Lake zooplankton commonly switch microhabitats on a regular day-night basis by migrating horizontally between stands of vegetation and open waters, or by migrating vertically between deep and surface waters. These movements have been explained in terms of the need to avoid predators (especially fish) and excessive ultraviolet radiation.  However, although zooplankton are known to seek […]

Planting vegetation to stop stream bank erosion: where’s the evidence?

June 19, 2017

0

Increased rates of stream bank erosion and sediment movement in disturbed catchments have been attributed to changes in catchment hydrology caused by land clearing, channel modification, the trampling activities of livestock and the removal of riparian vegetation. Given that these effects are human-induced, it’s commonly assumed that they can also be reversed by human intervention, […]

Herbivory is important in freshwater systems

March 27, 2017

Comments Off on Herbivory is important in freshwater systems

Until the 1990s it was believed that, in the main, freshwater and marine plants were connected to aquatic food webs only indirectly, through the breakdown of decaying vegetation by decomposers. However, over the last two decades there’s been a growing realisation that the activities of aquatic herbivores in consuming plants and channeling the derived nutrients […]

Unravelling trends in stream nitrogen

March 27, 2017

Comments Off on Unravelling trends in stream nitrogen

Oxides of nitrogen derived from agriculture, industry and emissions from the burning of fossil fuels fall out from the atmosphere and enter terrestrial and freshwater ecosystems. Over the last century the deposition of reactive nitrogen has increased three to five times, and this is reflected in a general global increase in stream nitrogen concentrations. However, at […]

Homing in on factor interactions

March 27, 2017

Comments Off on Homing in on factor interactions

In most cases the dynamics of ecological systems are best explained as responses to a number of interacting environmental factors, rather than to a single variable. Such interactions can be complex, and although they may have major implications for management, they’re typically very poorly understood. A team of Australian researchers has proposed a method for […]

Floating times of riparian seeds

March 27, 2017

Comments Off on Floating times of riparian seeds

Given the important role that the transport of water-borne seeds plays in the long-distance dispersal of riparian plants, surprisingly little is known about this process.   In laboratory experiments, a team of Australian and Chinese scientists measured the floating times of seeds collected from sixty species of Australian riparian plant species. Most species reached the test […]