Interplay between Senecio jacobaea and plant, soil, and aboveground insect community composition

To elucidate the factors that affect the performance of plants in their natural environment, it is essential to study interactions with other neighboring plants, as well as with above- and belowground higher trophic organisms. We used a long-term field experiment to study how local plant community diversity influenced colonization by the biennial composite Senecio jacobaea in its native range in The Netherlands in Europe. We tested the effect of sowing later-succession plant species (0, 4, or 15 species) on plant succession and S. jacobaea performance. Over a period of eight years, the percent cover of S. jacobaea was relatively low in communities sown with 15 or 4 later-succession plant species compared to plots that were not sown, but that were colonized naturally. However, after four years of high abundance, the density of S. jacobaea in unsown plots started to decline, and the size of the individual plants was smaller than in the plots sown with 15 or 4 plant species. In the unsown plots, densities of aboveground leaf-mining, flower-feeding, and stem-boring insects on S. jacobaea plants were lower than on plants in sown plots, and there was a strong positive relationship between plant size and levels of herbivory. In a greenhouse experiment, we grew S. jacobaea in sterilized soil inoculated with soil from the different sowing treatments of the field experiment. Biomass production was lower when S. jacobaea test plants were grown in soil from the unsown plots than in soil from the sown plots (4 or 15 species). Molecular analysis of the fungal and bacterial communities revealed that the composition of fungal communities in unsown plots differed significantly from those in sown plots, suggesting that soil fungi could have been involved in the relative growth reduction of S. jacobaea in the greenhouse bioassay. Our results show that, in its native habitat, the abundance of S. jacobaea depends on the initial composition of the plant community and that, on a scale of almost a decade, its interactions with plant and soil communities and aboveground invertebrates may influence the dynamics of this colonizing species.     

Multi-criteria evaluation of suitable locations for temporary disaster waste storage sites: the case of Cavite,Philippines

One of the problems that arise due to typhoon and flooding is the generation of large volumes of disaster wastes, which poses threats to the environment and human health when not managed properly. This study focused on the identification of suitable locations of temporary storage sites (TSS) for disaster wastes using geographic information system to address gaps in disaster waste management. A set of criteria for selection was established based on the guidelines of the United Nations Environment/Office for the Coordination of Humanitarian Affairs Joint Unit (UNEP/OCHA), with constraints set based on existing guidelines and past studies. Map layers were standardized using Boolean logic, and the criteria were analyzed using ArcGIS Pro and Google Earth Pro. Areas in the Province of Cavite having high disaster risks, particularly Cavite City, Noveleta, and Kawit, were selected as study sites. From the analysis, a total of 18 TSS candidates were identified. It was determined that land use and distances from fishponds and built-up areas were the most sensitive criteria as they cover large portions of the area. For each TSS candidate, a 15-min service area map was generated using the ArcGIS Pro Network Analyst which showed that selected locations may serve multiple cities/municipalities.

     

A Stereoselective Route to R-(+)-Limonene-Based Non-isocyanate Poly(hydroxyurethanes)

Journal of Polymers and the Environment - Bio-based non-isocyanate poly(hydroxyurethanes) (NIPUs) have recently gained significant interest due to increasing awareness of the health and...