Buried alive: Aquatic plants survive in ‘ghost ponds’ under agricultural fields

The widespread loss of wetlands due to agricultural intensification has been highlighted as a major threat to aquatic biodiversity. However, all is not lost as we reveal that the propagules of some aquatic species could survive burial under agricultural fields in the sediments of ‘ghost ponds’ - ponds in-filled during agricultural land consolidation. Our experiments showed at least eight aquatic macrophyte species to germinate from seeds and oospores, following 50–150 years of dormancy in the sediments of ghost ponds. This represents a significant proportion of the expected macrophyte diversity for local farmland ponds, which typically support between 6 and 14 macrophyte species. The rapid (< 6 months) re-colonisation of resurrected ghost ponds by a diverse aquatic vegetation similarly suggests a strong seed-bank influence. Ghost ponds represent abundant, dormant time capsules for aquatic species in agricultural landscapes around the globe, affording opportunities for enhancing landscape-scale aquatic biodiversity and connectivity. While reports of biodiversity loss through agricultural intensification dominate conservation narratives, our study offers a rare positive message, demonstrating that aquatic organisms survive prolonged burial under intensively managed agricultural fields. We urge conservationists and policy makers to consider utilizing and restoring these valuable resources in biodiversity conservation schemes and in agri-environmental approaches and policies

Ozone measurements with star-pointing spectrometers

Part 1 Historical frontiers: vibrational spectroscopic contributions to chemisorption and catalysis. Part 2 Instrumentation: recent advances in kinetic infrared spectroscopy; spectroscopic concentration determination without calibration; scope and limitations of concentration-modulated absorption spectroscopy; electrochemically modulated infrared spectroscopy using a step-scanning FTIR spectrometer; application to the Fe(CN)6 3-/Fe(CN)6 4- couple; applications of Raman microscopy and Raman imaging; an error model for near infrared spectroscopic instruments; the new possibilities of luminescence spectroscopy of microscopic matter; characterization of single hydrocarbon fluid inclusions by fluorescence excitation-emission micro-spectroscopy; spectroscopic imaging of polyethylene; ozone measurements with star-pointing spectrometers. Part 3 Nuclear magnetic resonance: recent advances in high-resolution chemical NMR spectroscopy of solids; SFC/NMR on-line coupling; structural determinations of organic compounds in the environment by NMR spectroscopy and mass spectrometry; solid state proton NMR and dynamic mechanical analysis studies of polymer latex blends. Part 4 Biological applications: speciation of selenium in human serum by size exclusion chromatography and inductively coupled plasma mass spectrometry; the investigation of varietal differences among sorghum crop residues using near infrared reflectance spectroscopy; the influence of energy migration on fluorescence kinetics in photosynthetic systems; flow injection procedures with spectrophotometric detection for the determination nitrate and nitrite in riverine, estuarine and coastal waters; quantitative determination of chlorophyll. Part 5 Spectrometric determinations. Part 6 Chemometrics. (Part contents)

Electrochemical sensing of volcanic gases

We report here the development and application of a compact “geochemical nose” incorporating electrochemical sensors for gas measurements in volcanic plumes. A novel element of the instrument design is the arrangement of the sensors in a parallel array that enables near-simultaneous exposure and fast response. Data analysis methods were developed that utilise the multi-sensor output currents to extract gas mixing ratio abundances and eliminate cross-sensitivities. Use of filter methods is demonstrated to remove baseline drift or instrument noise. We introduce a new approach for analysis of measurements from sensors that have a slower response time (e.g. HCl), and apply this model to estimate HCl/SO2 ratios. We deployed the sensor system at Aso volcano, Japan, detecting emissions from its fumarole field hot crater lake, and a mixed plume. We measured SO2, H2S, CO and HCl, ranging in abundance from ~ 102–104 ppbv. Neither NO2 nor Cl2 were detected. For the fumarolic gases, molar ratios were measured as follows: H2S/SO2 is ~ 0.15, H2/SO2 ~ 0.25, CO/SO2 ~ 0.02, HCl/SO2 ~ 0.1. The crater lake plume's H2S/SO2 is ~ 0.03. The compositions are discussed in terms of degassing equilibria and plume chemistry. Our instrument design represents a cost-effective, low-power and highly portable system that can be readily adapted for operational surveillance of volcanic gases