16 research outputs found
Economic assessment tool for greywater recycling systems
The implementation of water demand management strategies, particularly in urban environments, can contribute towards improved sustainability (or at least reduce unsustainability) in the water sector. Greywater treatment, and its subsequent use for toilet flushing, is one of the demand management options offering considerable water-saving potential. The uptake of greywater recycling systems (GRSs), particularly in the UK, is low. One of the reasons for such a low uptake is the perception that GRSs have a high (unsustainable) cost/benefit ratio. This paper presents progress on the development of a whole-life cost (WLC) model, aimed at facilitating decision making for the implementation of GRSs in relation to their economic viability
Ectomycorrhizal Colonization and Diversity in Relation to Tree Biomass and Nutrition in a Plantation of Transgenic Poplars with Modified Lignin Biosynthesis
Wood from biomass plantations with fast growing tree species such as poplars can be used as an alternative feedstock for
production of biofuels. To facilitate utilization of lignocellulose for saccharification, transgenic poplars with modified or
reduced lignin contents may be useful. However, the potential impact of poplars modified in the lignification pathway on
ectomycorrhizal (EM) fungi, which play important roles for plant nutrition, is not known. The goal of this study was to
investigate EM colonization and community composition in relation to biomass and nutrient status in wildtype (WT, Populus
tremula6Populus alba) and transgenic poplar lines with suppressed activities of cinnamyl alcohol dehydrogenase, caffeate/
5-hydroxyferulate O-methyltransferase, and cinnamoyl-CoA reductase in a biomass plantation. In different one-year-old
poplar lines EM colonization varied from 58% to 86%, but the EM community composition of WT and transgenic poplars
were indistinguishable. After two years, the colonization rate of all lines was increased to about 100%, but separation of EM
communities between distinct transgenic poplar genotypes was observed. The differentiation of the EM assemblages was
similar to that found between different genotypes of commercial clones of Populus6euramericana. The transgenic poplars
exhibited significant growth and nutrient element differences in wood, with generally higher nutrient accumulation in
stems of genotypes with lower than in those with higher biomass. A general linear mixed model simulated biomass of oneyear-
old poplar stems with high accuracy (adjusted R2 = 97%) by two factors: EM colonization and inverse wood N
concentration. These results imply a link between N allocation and EM colonization, which may be crucial for wood
production in the establishment phase of poplar biomass plantations. Our data further support that multiple poplar
genotypes regardless whether generated by transgenic approaches or conventional breeding increase the variation in EM
community composition in biomass plantations.Open-Access-Publikationsfonds 2013peerReviewe