Bioenergy Crops Energy crops: study shows increased biodiversity

Energy crops and in particular short rotation coppice, is being suggested to promote biodiversity while renewable energy is produced. According to a recent study (release date August 2014) in highly reputed scientific journal “BIOMASS AND BIOENERGY”, short rotation coppice (SRC) can reinforce functional biodiversity values. The study was conducted by researchers at Ghent University and The Flemish Institute for Technological Research (Belgium).

We wanted to follow our last post (5 reasons to cultivate renewable biomass) focused on how energy crops could improve food sustainability and land use implementing agricultural rotations, avoiding monocultures, not ploughing every year but giving more relevance to grasslands and forestry, then promoting increments in biodiversity with perennial species. Now this new study now have found clear evidence that SRC as energy crops (willow in this case) can be extremely valuable to improve current land use and fauna in Northern Europe.

Biodiversity and Short Rotation Coppice as energy crops

Researchers compared communities of vascular plants and arthropods in ten Short Rotation Coppice (SRC) used as energy crops –maize pairs, to (1) quantify the difference in diversity and composition between these two alternative land-use types and (2) to assess the potential of SRC plantations to increase functional biodiversity values in agricultural landscapes.

In each SRC energy crop plantation and maize field, the vegetation was surveyed and arthropods were sampled by applying pitfall and pan trapping.

The composition of the vegetation and of the epigeic and vegetation inhabiting arthropod communities strongly differed between the crop types. This differentiation was mainly due to true species turnover and only to a lesser extent to the occurrence of nested subsets.

Biodiversity and perennials: Willow trees producing biomass for renewable energy are harvested every 3, 4 or 5 years. Researchers found SRC consistently increased arthropod activity and densities for the different functional groups.

Short rotation coppice incrased densities!

On average, the total cover of the energy crops vegetation was 10 times higher in the SRC plantations and taxonomic and trait diversity were also consistently higher in SRC. Arthropod activity densities were significantly higher, sometimes almost double, in SRC plantations. Significantly higher effective species numbers in SRC were only retrieved for Hymenoptera and Coleoptera. Regarding functional groups, the activity densities of omnivores, detritivores, mycophages, phytophages and parasitoids were significantly higher in SRC. While activity densities of predators were not different among the crop types, their effective species number was higher in SRC, indicating a more evenly distributed and diverse predator community.

To conclude, authors have shown that energy crops as SRC can significantly increase vegetation and arthropod abundance and/or diversity in agricultural landscapes when replacing annual biomass crops, such as maize. Three of the four most dominant taxonomic groups showed a clearly higher activity density in SRC, whereas the effect of crop type on the effective species numbers were more variable, with even slightly higher numbers for Diptera in maize. This suggests that SRC plantations, at least those located in simple landscapes, mainly increased activity density of arthropods and only to a lesser extent the arthropod diversity at the field scale. Nevertheless, in line with the results for the vegetation, the dissimilarity in arthropod communities was mainly the result of species turnover. Hence, SRC plantations clearly provide additional habitats compared to maize, increasing the arthropod gamma diversity at the landscape scale.

These new findings are consistent with many others on energy crops and previous studies on willow as a better habitat for fauna.

Other sound article to read about bioenergy and biodiversity can be found here. But if you need more scientific evidence recently pubished we let here below an oustanding sound list of publications: