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Abstract: Several ongoing projects are harvesting maritime biomass from the Baltic Sea for eutrophication mitigation and utilisation of the recovered biomass. Some of this biomass comprises common reed (Phragmites australis), one of the most widespread vascular plants on Earth. Reed utilisation from eutrophied coastal areas needs to be evaluated. Therefore, a system analysis was performed of reed harvesting for biofuel and biofertiliser production. The specific objectives of the analysis were to: investigate the methane yield associated with anaerobic co-digestion of reed; make a primary energy assessment of the system; quantify Greenhouse Gas (GHG) savings when a fossil reference system is replaced; and estimate the nutrient recycling potential of the system. The results from energy and GHG calculations are highly dependent on conditions such as system boundaries, system design, allocation methods and selected indicators. Therefore a pilot project taking place in Kalmar County, Sweden, was used as a case study system. Laboratory experiments using continuously stirred tank reactor digesters indicated an increased methane yield of about 220 m3 CH4/t volatile solids from co-digestion of reed. The energy balance for the case study system was positive, with energy requirements amounting to about 40% of the energy content in the biomethane produced and with the non-renewable energy input comprising about 50% of the total energy requirements of the system. The net energy value proved to be equivalent to about 40 L of petrol/t reed wet weight. The potential to save GHG emissions compared with a fossil reference system was considerable (about 80%). Furthermore an estimated 60% of the nitrogen and almost all the phosphorus in the biomass could be re-circulated to arable land as biofertiliser. Considering the combined benefits from all factors investigated in this study, harvesting of common reed from coastal zones has the potential to be beneficial, assuming an appropriate system design, and is worthy of further investigations regarding other sustainability aspects. [Copyright &y& Elsevier]

There is a growing need to recover degraded soils to restore their essential ecosystem services and limit damages of anthropic activities onto these systems. Safe and sustainable solutions for long-term recovery must be designed, ideally by recycling existing resources. Using ash from combustion of residual forest biomass at the pulp and paper industry is an interesting and sustainable strategy to recover mining soils. However, formulations must be found to limit the potential toxicity associated with soluble salts and chloride that ash contains. Here, we assessed the effectiveness of three field ash-based amendments for the recovery of three highly acidic soils from Portuguese abandoned mines. Three amendments were tested: an un-stabilized mixture of ash and biological sludge, granulated ash, and granulated ash mixed with composted sludge. One year after application in open field plots (in the scope of LIFE No_Waste project), soil health restoration was evaluated through (i) soil physico-chemical characterization and (ii) soil habitat functions though standardized ecotoxicological tests. This study highlights that stabilized materials provided nutrients, organic matter and alkalinity that corrected soil pH and decreased metal bioavailability, while controlling the release of soluble salts and chloride from ash. This soil improvement correlated with improved soil model organisms' reproduction and survival. For similar amendment, the native soil properties studied (as soil native electrical conductivity) affected the level of organism response. This work provides evidence that ash stabilization, formulation and supplementation with organic matter could be sustainable strategies to restore highly degraded mining soils and to recover their ecological functions. It further highlights the importance of analyzing combined effects on soil physico-chemical properties and ecological function recovery to assess restoration strategy efficiencies in complex multi-stressor environments. • Ash-based formulations improved physico-chemical conditions in highly degraded mining soils. • Invertebrate reproduction benefits from stabilized ash granules and composted sludge application. • Organic carbon addition with composted sludge promotes E. crypticus reproduction. • Ash granulation reduced EC and soluble chloride-related hazard for model invertebrates. Ash-based amendments are a promising strategy to contribute to the recovery of mining soils' capacity to support ecosystems function and to recycling nutrients in relevant waste streams. [ABSTRACT FROM AUTHOR]

Abstract: In an effort to generate more information on the use of biosolids in the turf industry, a study was conducted to compare the effectiveness of biosolids with recommended organic sources in enhancing soil microbial populations and N availability in putting green sand rootzones. The treatments included four types of rootzones as follows: sand (control), sand mixed with Dakota reed-sedge peat (10%, v/v), sand mixed with yard-waste compost (10%, v/v), and sand mixed with biosolids (10%, v/v), which were established at the North Shore Country Club golf course, Glenview, IL, USA in 1997. All plots received the same fertilizers mainly in organic forms at 100kgNha−1 year−1. Creeping bentgrass (Agrostis palustris) turf was established, and was managed as a practice putting green. Soil microbial biomass in the rootzone (0–30cm) was higher either under compost (fall 2004 and summer 2005) or biosolids (summer 2003) than other treatments. Rootzone ammonium oxidizer populations were higher with biosolids (5400g−1 soil) than peat (1200g−1 soil) and compost (500g−1 soil) amendment and in control (400g−1 soil) in summer 2003. The nitrite oxidizer populations were higher with biosolids (24000g−1 soil) than compost (8300g−1 soil) and peat (4700g−1 soil) amendment and in control (3700g−1 soil) in summer 2005. Soil potentially mineralizable N, also being lowest in control, was higher in the biosolids-amended than compost- and peat-amended rootzones. In most seasons, the nitrate concentrations in biosolids rootzone (3.16–19.3mgkg−1) were higher than in compost (2.79–17.7mgkg−1), peat (1.83–14.4mgkg−1), and control rootzone (0.81–15.2mgkg−1). The study indicates that while compost could restore soil microbial biomass better than peat, biosolids could maintain greater N supply than peat and compost. [Copyright &y& Elsevier]