Evaluation of sedimentary bacterial community dynamics and contamination assessment of lower Des Plaines River

Urban rivers often contain elevated concentrations of contaminants such as organic pollutants and heavy metals which can be amplified in lotic ecosystems receiving effluents from wastewater treatment plants (WWTP). However, the impact of WWTPs on the microbial parameters of the urban river sediments has not been well documented compared to urban surface water. Collecting sediment samples at five different locations over a 9,000 m transect during four sampling periods, we investigated spatiotemporal variations of microbial parameters in sediments of lower Des Plaines River; the largest effluent-dominated stream in the United States and the effects of sediment physicochemical properties on the variations were explored. We reported reduced microbial biomass, CFUs, and distinct bacterial communities at the WWTP outfall compared to other sites, indicating that WWTP effluents have the potential to moderate bacterial community structure. Seasonal variations in the sedimentary bacterial community structure were evident regardless of the spatial variations imposed by the effluents. Our community-level physiological profiling of the sedimentary bacterial community structure indicated that temperature was more important than water chemistry, whereas total microbial biomass by phospholipid phosphate analysis responded to the influences of both temperature and water chemistry. Metal concentrations showed values that fall within the “fair” to “very poor” range of biological conditions outlined by the Midwest Biodiversity Institute. We posit that the increased sediment metal loads select for metal-tolerant microorganisms that help to maintain microbial biomass. In the spring, sequencing of bacterial 16S rRNA genes revealed significant effects of effluent on bacterial community composition at the WWTP outfall, showing increases in abundances of Caldilinea, Candidatus, Allochromatium, Sulfuritalea, and Nitrospira sequences, linked to anthropogenic inputs from WWTP effluents. Given that human dependence on effluent-dominated ecosystems for water resources will increase with rapidly increasing urbanization, studies focusing on remediation and policy changes are dire to develop effective management of existing urban rivers

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Litter decomposition across multiple spatial scales in stream networks

ISSN:0029-8549ISSN:1432-193

Global urban environmental change drives adaptation in white clover.

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale