Fish occurrence data to support high‐resolution distribution models and test various community and macroecological hypotheses have not been available at the national scale. We present IchthyMaps, a high‐resolution database of historical freshwater fish occurrences throughout the conterminous United States. Designed on the principles of metacommunity ecology, IchthyMaps is a large compilation of fish presence records collected through approximately 1990, digitized from regional atlases, appended to 1:100,000 National Hydrography Dataset plus version 2 (NHDPlusV2) interconfluence stream segments, and readily aggregated within hierarchically coarser units (e.g., 8‐digit and 12‐digit U. S. Geological Survey [USGS] hydrologic units). IchthyMaps contains 606,550 presence records for 1,038 species and subspecies, spatially joined to 224,305 NHDPlusV2 interconfluence stream segments, representing more than 10% average sampling intensity considering all the NHDPlusV2 segments as the sampling frame. IchthyMaps is freely and publicly accessible through the USGS ScienceBase web portal. It offers new opportunities for both basic and applied research and conservation programs in areas such as modeling species distributions, community ecology, gap analysis, and assessments of impacts of land use, species invasions, climate change, conservation biogeography, and fisheries management.

No abstract

We conducted a 3 × 3 × 2 experiment to verify the moral preference hypothesis and extend the boundary conditions of the moral frame effect. Participants played a trade-off game (TOG), in which they unilaterally choose between an equitable or efficient option. We manipulated the labeling of the options to describe the equitable versus efficient option as morally right, and controlled the amount of the stakes and division schemes in the TOG. We found there was a significant effect of moral frame when stakes were low in the TOG, and participants would choose a morally right option whether it was equitable or efficient. However, the effect of moral frame was nonsignificant when the stakes were high. In addition, the division schemes in the TOG had a great impact on the moral frame effect. Therefore, we found that when participants’ interest in the options remains the same or the changes are small, and other players’ interest changes greatly, the moral frame effect is not significant.

Abstract. The Amsterdam area, a highly manipulated delta area formed by polders and reclaimed lakes, struggles with high nutrient levels in its surface water system. The polders receive spatially and temporally variable amounts of water and nutrients via surface runoff, groundwater seepage, sewer leakage, and via water inlets from upstream polders. Diffuse anthropogenic sources, such as manure and fertiliser use and atmospheric deposition, add to the water quality problems in the polders. The major nutrient sources and pathways have not yet been clarified due to the complex hydrological system in lowland catchments with both urban and agricultural areas. In this study, the spatial variability of the groundwater seepage impact was identified by exploiting the dense groundwater and surface water monitoring networks in Amsterdam and its surrounding polders. A total of 25 variables (concentrations of total nitrogen (TN), total phosphorus (TP), NH 4 , NO 3 , HCO 3 , SO 4 , Ca, and Cl in surface water and groundwater, N and P agricultural inputs, seepage rate, elevation, land-use, and soil type) for 144 polders were analysed statistically and interpreted in relation to sources, transport mechanisms, and pathways. The results imply that groundwater is a large source of nutrients in the greater Amsterdam mixed urban-agricultural catchments. The groundwater nutrient concentrations exceeded the surface water environmental quality standards (EQSs) in 93 % of the polders for TP and in 91 % for TN. Groundwater outflow into the polders thus adds to nutrient levels in the surface water. High correlations (R 2 up to 0.88) between solutes in groundwater and surface water, together with the close similarities in their spatial patterns, confirmed the large impact of groundwater on surface water chemistry, especially in the polders that have high seepage rates. Our analysis indicates that the elevated nutrient and bicarbonate concentrations in the groundwater seepage originate from the decomposition of organic matter in subsurface sediments coupled to sulfate reduction and possibly methanogenesis. The large loads of nutrient-rich groundwater seepage into the deepest polders indirectly affect surface water quality in the surrounding area, because excess water from the deep polders is pumped out and used to supply water to the surrounding infiltrating polders in dry periods. The study shows the importance of the connection between groundwater and surface water nutrient chemistry in the greater Amsterdam area. We expect that taking account of groundwater-surface water interaction is also important in other subsiding and urbanising deltas around the world, where water is managed intensively in order to enable agricultural productivity and achieve water-sustainable cities.

Abstract:With the rapid development of the photovoltaic industry, fault monitoring is becoming an important issue in maintaining the safe and stable operation of a solar power station. In order to diagnose the fault types of photovoltaic array, a fault diagnosis method that is based on the Least Squares Support Vector Machine (LSSVM) in the Bayesian framework is put forward. First, based on the elaborate analysis of the change rules of the output electrical parameters and the equivalent circuit internal parameters of photovoltaic array in different fault states, the input variables of the photovoltaic array fault diagnosis model are determined. Second, through the LSSVM algorithm in the Bayesian framework, the fault diagnosis model based on the output electrical parameters and the equivalent circuit internal parameters of the photovoltaic array is built, which can effectively detect the photovoltaic array faults of short circuit, open circuit, and abnormal aging. Then, the simulation model is built to verify the validity of the LSSVM algorithm in the Bayesian framework by comparing it with the model of LSSVM and the Support Vector Machine (SVM). Moreover, a 5 × 3 photovoltaic array and a reference photovoltaic string are established and experimentally tested to validate the performance of the proposed method.