[1] We made continuous measurements of the flux of dissolved oxygen over an algal-dominated reef flat community on the Kaneohe Bay Barrier Reef, Hawaii as a proxy for the net production (NP) of organic carbon. Fluxes were calculated from measurements of dissolved oxygen and current profiles taken from moored oxygen sensors and acoustic Doppler current profilers (ADCPs) located at points defining the vertices of a triangular control volume 250 m in length on each side. Surface cruciform drifters as well as dye patches were tracked across the control volume to get independent measurements of Lagrangian currents. While the dye patch speeds were highly correlated with the depth-averaged current speeds calculated from ADCP data on a 1:1 basis (r 2 = 0.86, n = 24), drifter speeds exceeded both dye and calculated current speeds by 30-100% on average. Measurements of dissolved oxygen sampled within the dye patches as it propagated across the study site were used to calculate NP following a Lagrangian approach. Lagrangian estimates of NP were highly correlated with Eulerian estimates of NP on a 1:1 basis (r 2 = 0.81, n = 7). Ratios of community production and community respiration varied from 0.7 to 1.4 on a daily basis, but approached a value of 1.0 when integrated over the entire data record.

Particulate matter concentration (PM, often referred to as total suspended solids [TSS]) is an important parameter in the evaluation of water quality. Several optical measurements used to provide an estimate of water turbidity have also been used to estimate PM, among them light transmission, backscattering, and side-scattering. Here we analyze such measurements performed by the Alliance for Coastal Technologies (ACT) at various coastal locations to establish whether a given optical method performs better than others for the estimation of PM. All the technologies were found to perform well, predicting PM within less than 55% relative difference for 95% of samples (n = 85, four locations). Backscattering performed best as a predictor of PM, predicting PM with less than 37% relative difference for 95% of samples. The correlation coefficient (R) was between 0.96 and 0.98 for all methods with PM data ranging between 1.2 to 82.4 g m -3. In addition, co-located measurements of backscattering and attenuation improves PM prediction and provides compositional information about the suspended particles; when their ratio is high, the bulk particulate matter is dominated by inorganic material while when low, dominated by organic material.

Larvae of the California newt (Taricha torosa) exhibit striking predator‐avoidance behavior, escaping to refuges in response to a chemical cue from cannibalistic adults. In laboratory flow‐tank experiments, stream water collected near free‐ranging adults induced hiding responses in 100% of the larvae tested. Solutions prepared by bathing adults (in field and laboratory) also evoked strong hiding behaviors. Insensitive to adult feeding status (fed or starved), and clearly not an excretory product, the chemical cue was released from adult skin (i.e., in swabs of adult backs, sides, and bellies). Tetrodotoxin (TTX) was found in skin swabs of adults and in bathwater at 1 × 10−7 mol/L using reversed‐phase high‐pressure liquid chromatography (HPLC). Concentrations of 1 × 10−7 to 1 × 10−9 mol/L TTX standard, and equivalent dilutions of bathwater, triggered hiding behaviors in larvae, with no subsequent sublethal toxicity. The presence of TTX‐sensitive cells within larval olfactory epithelium was confirmed by behavioral experiments and electrophysiological recordings. In contrast, larvae did not hide in response to two other, structurally mimetic compounds (saxitoxin and μ‐conotoxin GIIIB). Ontogenetically, larval behavioral responses to TTX and bathwater were strongest during weeks 3–5, diminishing to nil during week 7. No longer susceptible to adult cannibalism, larval indifference to the cue coincided with their ability to climb out of water and onto land. Thus, newt larvae escape cannibalism by detecting a poison (TTX) well known as a chemical defense for conspecific adults. Eliciting a behavioral response in one case and inhibiting neural activity in the other, this compound results in opposing physiological effects, with avoiding predation as the common goal. Accordingly, TTX joins a select group of keystone molecules, each having critical, but different, ecological consequences at multiple trophic levels. The unique combination of bioactive properties makes a compelling case for asymmetrical selection as a force driving the evolution of adult–larval trophic interactions.

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Transport accounts for 31% of Swiss green house gas emissions due to the high degree of oil dependence in transport energy supply. The emissions of transport could be reduced significantly if all the vehicles that ran on fossil fuels would be replaced by electric vehicles powered by photovoltaic solar energy. Compared with other sources of renewable transport energy, photovoltaic generation of electricity has two advantages: it requires little space and can also be applied to built-up areas or transport infrastructure. In this paper, we will examine the potential of parking lots for the photovoltaic generation of solar electricity. The paper is based on simulations that were carried out for 48 parking lots in Frauenfeld, a typical Swiss medium-sized city of 22 665 inhabitants. Covered with solar carports, these parking lots alone would cover 15-40% of the energy demand by the city's road passenger transport.