A new paper published in Science Advances has stated that the world's forests are fragmented and deteriorating. The authors analyzed the satellite imagery and compiled the data from long-term fragmentation studies, and came to a conclusion that 70% of the remaining forest land exists within 1 km of an edge, which has negative impacts on their fauna, flora and ecosystem services.

Nick Hadded, corresponding author of Habitat fragmentation and its lasting impact on Earth's ecosystems, said, "Nearly 20% of the world's remaining forest is the distance of a football field-or about 100 meters-away from a forest edge".

Hadded added that 70% of the forest lands are within a half-mile of a forest edge due to which almost no forest can really be considered wilderness.

The authors have reported that the development, agricultural expansion and urban growth have rapidly carved the natural areas into very smaller sections.

For example, in Brazil's Atlantic Forests less than 9% of the remaining intact areas are farther than 1km from an edge.

The authors figured out that when these findings were coupled with a meta-analysis of seven long-term fragmentation experiments on five continents, they painted an alarming outlook for the future of our forests.

In a press release, Hadded said that although the initial negative effects were not surprising for him, he was blown away by the fact that these negative effects have become even more negative with time.

He gave an example that some results showed a 50% or higher decline in plant and animals species over an average of just 20 years and the trajectory was still spiraling downward.

The authors mentioned that fragmentation not only leads to the reduction of birds, mammals and insects and diversity, but the small patches of forest also alter nutrient cycles which result in the reduction of biomass, productivity and capacity to retain nitrogen and carbon.

In the experiments that were done in the tropics, the authors have also found that small fragment sizes can result in the eventual death of large, old-growth trees.