Multiple metals influence distinct properties of the Arabidopsis circadian clock

Circadian rhythms coordinate endogenous events with external signals, and are essential to biological function. When environmental contaminants affect these rhythms, the organism may experience fitness consequences such as reduced growth or increased susceptibility to pathogens. In their natural environment plants may be exposed to a wide range of industrial and agricultural pollutants. Here, we investigate how the addition of various metal salts to the environment can impact plant-circadian rhythms, via the promoter:luciferase system. The consequences of these environmental changes were found to be varied and complex. Therefore, in addition to Fourier-based analyses, we apply novel wavelet-based spectral hypothesis testing and clustering methodologies to organize and understand the data. We are able to classify broad sets of responses to environmental contaminants, including pollutants which increase, or decrease, the period, or which induce a lack of precision or disrupt any meaningful periodicity. The methods are general, and may be applied to discover common responses and hidden structures within a wide range of biological time series data.

Development of Ecological Strategies for the Recovery of the Main Nitrogen Agricultural Pollutants: A Review on Environmental Sustainability in Agroecosystems

Nitrogen (N) is a fundamental nutrient for plant growth and for the performance of biological functions. In agroecosystems, nitrogen fertilization is aimed at providing a suitable N dose for crop growth, avoiding the impoverishment or the improper enrichment of nitrogen compounds in soil. The high application of nitrogen fertilizers is the main cause of the increase in nitrate leaching and loss of the quality of natural resources (groundwater and soil). In the last decades, new sustainable technological approaches have been developed and applied on laboratory and field scales to reduce the impacts of nitrogen pollution on the environmental matrices and to improve the sustainability of agricultural management. This review highlights the results of the implementation of sustainable remediation new strategies to reduce pollution from a main agricultural contaminant (nitrate) and describes the benefits obtained from the use of these solutions in agroecosystems.

Widespread underestimation of the danger of groundwater contamination by shortcuts into aquifers

<p>Groundwater pollution threatens human and ecosystem health in many areas around the globe. Shortcuts to the groundwater through enlarged cracks and fissures, often referred to as concentrated recharge, are known to transmit short-lived pollutants into carbonate aquifers endangering water quality of around a quarter of the world population. However, the large-scale impact of concentrated recharge on water quality remains poorly understood. Here we apply a continental-scale model to quantify for the first time the danger of groundwater contamination by degradable pollutants through concentrated recharge in carbonate rock regions. We show that concentrated recharge is the primary reason for the rapid transport of contaminants to the groundwater, increasing the percentage of non-degraded pollutants from <1% in areas without concentrated recharge to around 20-50% in areas where concentrated recharge is present. Our findings are most pronounced in the Mediterranean region where agricultural pollutants in groundwater recharge like Glyphosate can exceed allowed concentrations by up to 19 times. Our results imply that in regions where shortcuts to the groundwater exist, continuing industrial agricultural productivity to optimize food production may result in a widespread reduction of available drinking water and harm ecosystem services more intense than presently available large-scale modelling concepts suggest.</p>