Category Archives: Ecosystems

0213001849

Urban Forests Can’t Restore Themselves Without Human Help

Native tree recruitment…required localized burning and herbivore exclusion,” the authors note. Burning eliminated competing plants and keeping rodents and deer away from the seedlings allowed them to grow. “The damage done by white-tailed deer is well-documented,” Whereas wildland forests have been studied extensively, less is known about an urban system. “If a forest isn’t replacing itself, it’s a garden, Just standing back and letting trees grow is not going to work.” (Click on title for full story.)

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Seagrass Meadows Protect Corals And Marine Animals From Our Filth

Our results indicated that seagrass meadows significantly reduce bacterial loads and can benefit both humans and other organisms in the environment. Represented on every continental shelf but Antarctica, seagrasses are valued for nutrient cycling, sediment stabilization, reduc ing the effects of carbon dioxide elevation, and providing nursery habitat for fisheries.Our observation of reduced levels of coral disease on reefs adjacent to seagrass meadows offers independent support of the benefits that seagrass meadows provide to controlling pathogenic bacteria in marine environments. (Click on title for full story.)

0213001849

Devastated Rain Forests Aren’t Just Going To Restore Themselves

The results of the research have implications for the restoration of rainforests: “It is highly unlikely that the tree species we studied is able to recolonise cleared patches in a fragmented habitat by natural seed dispersal alone,” says Kettle. He adds that the same applies to other endangered species of tropical tree with large fruit and seeds dispersed by birds, as evidence from other fragmented tropical forests around the world shows that seeds of this kind are dispersed only locally. “For rainforest restoration projects to be successful, you have to give special attention to these trees,” says Kettle. “If you want to encourage them to spread, the only option is to collect their seeds, set up tree nurseries and then actively plant out the saplings at a later stage.” (Click on title for full story.)

0213001849

Coastal Wetlands Uniquely Valuable To Slow Climate Change

All told, coastal wetlands may capture and store more than 200 metric tons of carbon per year globally. Importantly, these ecosystems store 50-90 percent of this carbon in soils, where it can stay for thousands of years if left undisturbed. “When we destroy coastal wetlands, for coastal development or aquaculture, we turn these impressive natural carbon sinks into additional, significant human-caused greenhouse gas sources,” (Click on title for full story.)

0213001849

Discovering A Huge Carbon Sink Hidden Under Our Very Feet

Peat is usually associated with cold places, not the middle of the hot, humid, Congo Basin. It’s an organic wetland soil made of partially-decomposed plant debris. In waterlogged places those plants can’t entirely decompose, and are not respired as carbon dioxide into the atmosphere. The peat thus builds up slowly, locking up ever-more carbon. The amounts involved are huge: peat covers just 3% of Earth’s land surface, but stores one-third of soil carbon. We knew that peat can be formed under some tropical swamp forests. Might the world’s second largest tropical wetland, known as the Cuvette Centrale, overlie peat? (Click on title for full story.)

0213001849

Longest-lived Tree Species Defends Itself Against Deadly Pine Beetle

Great Basin bristlecone pine has the longest lifespan of any non-clonal organism worldwide. We found that mountain pine beetle, a native insect which has killed millions of pine trees in the past decade, is not attracted to Great Basin bristlecone pine. (Click on title for full story.)

0213001849

Good Intentions Gone Bad: Pollinator Seed Mixes Spread Invasive Weeds

We don’t have any issues at all with the concept behind the pollinator habitat program; it’s a good program. But as a result of this program, we’ve now introduced Palmer amaranth to potentially thousands of acres of land, and we need to know what we are going to be allowed to do to try to stem the spread of it. And we need to do that quickly. (Click on title for full story.)

0213001849

Local Forest Die-Offs Have Far Reaching Effects (All Forests Are Global)

The new study describes how major forest losses can alter global climate by shifting the path of large-scale atmospheric waves or changing the amount of sunlight absorbed in the Northern versus the Southern hemispheres. Such changes can shift tropical rain bands and other climate features. (Click on title for full story.)

0213001849

Unfair! Invasive Plants Succeed By Inhibiting The Competition

Allelochemicals, released from the roots, leaves, and/or other parts of a plant, can negatively impact neighboring species. The “novel weapons hypothesis” suggests that allelochemicals from invasive plants may have a negative effect on native plants because they have not yet been able to evolve tolerance or resistance to the chemicals . The effects of allelochemicals can be direct or indirect. For example, germination and/or growth may be directly affected. Indirect effects can also occur when allelochemicals modify interactions in the soil, including mycorrhizal associations. (Click on title for full story.)

0213001849

Preserving Forests Makes Farms Better

The literature review showed that trees on farms and in agricultural landscapes in most cases result in improved food security via, e.g., reduced pest problems, improved soil fertility and water regulation. The positive effects were most consistent in semi-arid areas. In general, trees in the agricultural landscape were positive, but in some cases a decline in production of particular crops was noted as a trade-off. Very few of the available studies had investigated the production of wood, medicinal products, fruits and nuts, and no studies had looked at cultural ecosystem services such as recreation and spiritual values. This makes it difficult to establish all the synergies and trade-offs associated with trees in the landscape. (Click on title for full story.)