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Phosphorus (P) is essential for all living things and an integral part of food production. However, significant amounts of P are functionally lost when wastewater byproducts, such as biosolids or sewage sludge incinerator ash (SSA), are not beneficially reused. Around 20% of sewage sludge produced in the US is incinerated and nearly 25% of sewage sludge is incinerated in European Union member countries. SSA contains significant amounts of P (up to 14% total P) and other beneficial elements but is typically sent to landfills for disposal. However, SSA has also been explored as one method of capturing and redirecting P back into the food system. Research investigating SSA characterization, P availability, and contaminant concentrations and behavior in soil is required to understand the effects of SSA land application on soil chemical properties and crop production. Several approaches for recovering P from SSA have been investigated that consider these factors. Ultimately, the opportunity for land application of SSA depends on the individual characteristics of a given SSA, ex. total P and contaminant concentrations, and the requirements and regulations of the region where it is produced and applied. In this review, we address the history of P recovery from SSA and discuss research regarding characterization, contaminants, P availability, and land application of SSA. [Display omitted] • Sewage sludge ash, currently landfilled, is a potential P source for crop growth. • Ash properties depend on influent, sludge treatment, and incinerator temperature. • Treated ash can have improved qualities but economic tradeoffs should be explored. • More studies are required to understand agronomic effects of sewage sludge ash. [ABSTRACT FROM AUTHOR]

Abstract: The southeastern Madagascan endemic and monotypic genus Eligmocarpus is highly threatened due to a combination of factors. Firstly, general human-induced habitat destruction and fragmentation has degraded the environment in which it occurs, leading to an increased threat of extinction for itself and other co-occurring species. Secondly, and more specifically to Eligmocarpus, the desirable properties of its timber, which is an excellent construction material, has led to over-collection beyond levels of sustainability. Thirdly, and with the highest relevance for this project, it is a combination of mode of dispersal, germination and seedling establishment. For all these reasons, its range has contracted and the only remaining population (21 trees) is located in Petriky, a future mining site. In this study we investigate the phylogeography and population dynamics of Eligmocarpus based on molecular tools (not only conducted on extant individuals but also using herbaria preserved DNA from individuals from neighbouring populations which are no longer alive, to give a glimpse of the past). Prior to human colonisation, the species was successful in using the river network to invade several biomes (most likely from the humid to subarid, where it is now constrained). Hence, due to its location, Petriky is a mosaic of the genetic variability from populations higher up in the river network, therefore, despite the low number of remaining individuals, all hope of restoration is not lost. Within this project we hope that a more complete understanding of the evolution of the flora will allow conservation, not only of current patterns of variation, but also the processes that gave rise to these patterns. [Copyright &y& Elsevier]