The ecotoxicity of biosolids has been studied extensively using single-compound toxicity testing and ‘spiking’ studies; however, little knowledge exists on the ecotoxicity of biosolids as they are land-applied in the Canadian context. The purpose of this study is to elucidate the chronic, sublethal (i.e., behavioural), and lethal impacts of land- applying biosolids on the environmentally-relevant Folsomia candida (springtails) and Lumbricus terrestris (earthworms) and concomitantly ascertain whether the use of biosolids for nutrient amendment is a sustainable practice. This study is part of a larger multi-compartment program which includes terrestrial plants and aquatic arthropods. After an extensive review of government protocols and existing research in the literature, the current study attempted to elucidate the true nature of the potential ecotoxicity of land-applying biosolids, within a laboratory context. Protocols were developed or modified (e.g., using Evans’ boxes (Evans 1947) for chronic and sublethal testing on L. terrestris). Subsequently, two biosolids were tested on springtails and earthworms using avoidance and reproductive bioassay endpoints, at application rates that are standard (8 tonnes ha-1) and worst-case scenarios (22 tonnes ha-1). Results indicated no effect of biosolids at the environmentally-relevant concentration; the worst-case scenario exhibited a positive significantly significant relationship (indicating preference for treatment conditions). We suggest that further assessment of the potential ecotoxicological impact of biosolids employ i) environmentally-relevant organisms, ii) appropriate bioassays including the use of whole-organism endpoints, and iii) multi-kingdom testing (e.g., Kingdom Plantae, Animalia) to comprehensively elucidate answers. Lastly, in situ (field assays) are strongly encouraged in future studies.

Cities are the keystone landscape features for achieving sustainability locally, regionally, and globally. With the increasing impacts of urban expansion eminent, policymakers have encouraged researchers to advance or invent methods for managing coupled human–environmental systems associated with local and regional sustainable development planning. Although progress has been made, there remains no universal instrument for attaining sustainability on neither regional nor local planning scales. Previous sustainable urbanization studies have revealed that landscape configuration metrics can supplement other measures of urban well-being, yet few have been included in public data dashboards or contrasted against local well-being indicators. To advance this sector of sustainable development planning, this study had three main intentions: (1) to produce a foundational suite of landscape ecology metrics from the 2007 land cover dataset for the City of Toronto; (2) to visualize and interpret spatial patterns of neighborhood streetscape patch cohesion index (COHESION), Shannon’s diversity index (SHDI), and four Wellbeing Toronto indicators across the 140 Toronto neighborhoods; (3) to quantitatively assess the global collinearity and local explanatory power of the well-being and landscape measures showcased in this study. One-hundred-and-thirty landscape ecology metrics were computed: 18 class configuration metrics across seven land cover categories and four landscape diversity metrics. Anselin Moran’s I-test was used to illustrate significant spatial patterns of well-being and landscape indicators; Pearson’s correlation and conditional autoregressive (CAR) statistics were used to evaluate relationships between them. Spatial “hot-spots” and/or “cold-spots” were found in all streetscape variables. Among other interesting results, Walk Score® was negatively related to both tree canopy and grass/shrub connectedness, signifying its lack of consideration for the quality of ecosystem services and environmental public health—and subsequently happiness—during its proximity assessment of socioeconomic amenities. In sum, landscape ecology metrics can provide cost-effective ecological integrity addendum to existing and future urban resilience, sustainable development, and well-being monitoring programs.

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