A century later, plant biodiversity struggles in wake of agricultural abandonment

Aerial view of trees and fields.

(University of Minnesota) Researchers compared plots of abandoned farmland to nearby land that has not been significantly impacted by human activity. They found that one year after abandonment, the fields had, on average, 38 percent of the plant diversity and 34 percent of the plant productivity for the land that was never plowed; 91 years after abandonment, the fields still had only 73 percent of the plant diversity and 53 percent of the plant productivity.

Power lines may mess with honey bees’ behavior and ability to learn

Image of person in field of flowers beneath power lines.

(Science News) In the lab, honey bees were more aggressive toward other bees after being exposed to electromagnetic fields at strengths similar to what they might experience at ground level under electricity transmission lines. Those exposed bees also were slower to learn to respond to a new threat than unexposed bees were.

New fossil pushes back physical evidence of insect pollination to 99 million years ago

Artist rendering of the newly-discovered beetle.

(Indiana University) The revelation is based upon a tumbling flower beetle with pollen on its legs discovered preserved in amber deep inside a mine in northern Myanmar. This discovery pushes back the earliest documented instance of insect pollination to a time when pterodactyls still roamed the skies – or about 50 million years earlier than previously thought.

Urbanization delays spring plant growth in warm regions

Image of flowering tree by lake in park.

(Florida Museum) The first appearance of bright green leaves heralds the start of spring, nudging insects, birds and other animals into a whirlwind of action. But a new study shows that urbanization shifts this seasonal cue in nuanced ways, with cities in cold climates triggering earlier spring plant growth and cities in warm climates delaying it. The study also found that the urban heat island effect is not the only culprit behind the shift, suggesting that other aspects of urbanization, such as pollution, changes in humidity and fertilizer runoff, may also influence plants’ seasonal patterns.

Helpful insects and landscape changes

Image of potato beetle.

(Michigan State University) “One of the take-homes from our review is that natural enemies can be more abundant when agricultural landscapes are made up of smaller farm fields. Some natural enemies need resources found in other habitats or in crop field edges. We think when habitat patches are small, they are more likely to find their way back and forth between these habitats and crop fields, or from one crop field into another.”

Insect decline more extensive than suspected

Image of farmland.

(Technical University of Munich) Researchers collected more than one million insects at 300 sites. They were able to prove that many of the nearly 2,700 investigated species are in decline. In recent years, certain rare species could no longer be found in some of the regions studied. Both in forested areas and grasslands, the scientists counted about one third fewer insect species after 10 years.

Using probiotics to protect honey bees against fatal disease

Image of honey bees at entrance to hive.

(Western University) A group of researchers combined their expertise in probiotics and bee biology to supplement honey bee food with probiotics, in the form of a BioPatty, in their experimental apiaries. The aim was to see what effect probiotics would have on honey bee health. In the bee hives treated with probiotics, pathogen load was reduced by 99 percent, and survival-rate of the bees increased significantly.

Robust evidence of declines in insect abundance and biodiversity

Image of meadow plant bug on leaf.

(Nature) Rumors of insect declines have been around for some time. However, much of this evidence has come from biodiversity databases — records of species sightings, mostly collected by volunteers, and usually gathered in a haphazard fashion. Seibold and colleagues finally fill the gap by reporting species richness, abundance and biomass for a wide range of arthropod taxa recorded using standardized sampling. The results show clear evidence of substantial declines in arthropod abundance and biodiversity.