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Regional hydraulic geometry curves, which relate drainage area to channel morphology, are powerful tools for river restoration and watershed management. While there is a strong correlation between channel morphology and drainage area, the importance of watershed slope and relief on channel-forming flow, especially in mountainous regions, cannot be ignored. This research used single variable power functions along with multiple regression to determine which network- and or local-scale variables are influencing channel morphology in the Southern Blue Ridge Mountains. Within this region, watershed topography (i.e. relief and slope) and or local-scale characteristics (e.g. channel slope and sinuosity) are better predictors of channel morphology than drainage area. Additionally, the importance of local-scale characteristics in the multiple regression models provide strong evidence that site-specific conditions can be just as important as watershed characteristics in determining channel morphology. While multiple regression has been used to create hydraulic geometry equations in other regions, this is the first study that determined whether non-drainage area multiple regression models perform better than models that include drainage area. With the increasing ease with which network- and local-scale characteristics can be calculated, this research shows a clear need to incorporate additional network- and or site-specific characteristics into hydraulic geometry equations. [ABSTRACT FROM AUTHOR]

Water has always been a driver of human civilization. The first human civilizations thrived in places with an abundance of water, typically nearby large rivers as the Tigris–Euphrates, Yang Che and Nile. The invention and construction of hydraulic infrastructure came only later, in prehistoric times, triggered by the expansion of humanity in water-scarce areas. The ancient Greeks invented impressive hydraulic works and small-scale structures, some of which, such as cisterns, were still fully operational until the 20th century. We present a model that explains the use of cisterns in the water-scarce area of West Mani, which allows us to assess the potential of this traditional rainfall harvesting practice to support the modern water supply needs. To assess the system’s reliability, we employ a long-term simulation of a typical cistern system, using synthetic rainfall series from a stochastic model, and assuming variable water demand on a monthly scale. We show that a proper restoration of the cisterns could be sustainable as a complementary water supply source, decreasing the area’s drinking water cost and increasing the locals’ resilience against water shortages. In addition, we highlight the links between the area’s hydroclimate and its history and discuss the cultural merits of reviving and preserving this centuries-long practice.

Water has always been a driver of human civilization. The first human civilizations thrived in places with an abundance of water, typically nearby large rivers as the Tigris–Euphrates, Yang Che and Nile. The invention and construction of hydraulic infrastructure came only later, in prehistoric times, triggered by the expansion of humanity in water-scarce areas. The ancient Greeks invented impressive hydraulic works and small-scale structures, some of which, such as cisterns, were still fully operational until the 20th century. We present a model that explains the use of cisterns in the water-scarce area of West Mani, which allows us to assess the potential of this traditional rainfall harvesting practice to support the modern water supply needs. To assess the system's reliability, we employ a long-term simulation of a typical cistern system, using synthetic rainfall series from a stochastic model, and assuming variable water demand on a monthly scale. We show that a proper restoration of the cisterns could be sustainable as a complementary water supply source, decreasing the area's drinking water cost and increasing the locals' resilience against water shortages. In addition, we highlight the links between the area's hydroclimate and its history and discuss the cultural merits of reviving and preserving this centuries-long practice. [ABSTRACT FROM AUTHOR]

This study evaluates the relationship between both commercial and scientific spatial fisheries data and a new satellite‐based estimate of potential fish production (Ocean Productivity available to Fish, OPFish) in the European Seas. To construct OPFish, we used productivity frontal features derived from chlorophyll‐a horizontal gradients, which characterize 10%–20% of the global phytoplankton production that effectively fuels higher trophic levels. OPFish is relatively consistent with the spatial distribution of both pelagic and demersal fish landings and catches per unit of effort (LPUEs and CPUEs, respectively). An index of harvest relative to ocean productivity (HP index) is calculated by dividing these LPUEs or CPUEs with OPFish. The HP index reflects the intensity of fishing by gear type with regard to local fish production. Low HP levels indicate lower LPUEs or CPUEs than expected from oceanic production, suggesting over‐exploitation, while high HP levels imply more sustainable fishing. HP allows comparing the production‐dependent suitability of local fishing intensities. Our results from bottom trawl data highlight that over‐exploitation of demersal species from the shelves is twice as high in the Mediterranean Sea than in the North‐East Atlantic. The estimate of HP index by dominant pelagic and demersal gears suggests that midwater and bottom otter trawls are associated with the lowest and highest overfishing, respectively. The contrasts of fishing intensity at local scales captured by the HP index suggest that accounting for the local potential fish production can promote fisheries sustainability in the context of ecosystem‐based fisheries management as required by international marine policies. [ABSTRACT FROM AUTHOR]

The discovery of anaerobic ammonia oxidation (anammox) expanded our knowledge on the microbial nitrogen cycle. Previous studies report that anammox bacteria are distributed in a wide range of habitats and plays significant roles in the global nitrogen cycle. However, most studies focus only on individual ecosystems or datasets from public databases. To date, our understanding of how anammox bacteria respond to environmental properties and are distributed in different habitats on a global scale, remain unclear. To explore the global distribution of anammox bacteria, samples were collected from different habitats at different locations globally, including wetlands, drylands, groundwater aquifers and snow from 10 countries across six continents. We then used high-throughput amplicon sequencing targeting the functional gene hydrazine synthase (HZS) and generated community profiles. Results showed that Candidatus Brocadia is detected as the dominant genus on a global scale, accounting for 80.0% to 99.9% of the retrieved sequences in different habitats. The Jettenia-like sequences were the second most abundant group, accounting for no more than 19.9% of the retrieved sequences in all sites. The samples in drylands, wetlands and groundwater aquifers showed similar community composition and diversity, with the snow samples being the most different. Deterministic processes seem stronger in regulating the community composition of anammox bacteria, which is supported by the higher proportion explained by local-scale factors. Groundwater aquifers showed high gene abundance and the most complex co-occurrence network among the four habitat types, suggesting that it might be the preferred habitat of anammox bacteria. There is little competition between anammox bacterial species based on co-occurrence analysis. Hence, we could infer that environmental factors such as anaerobic and stable conditions, instead of substrate limitations, may be vital factors determining the anammox bacteria community. These results provide a better understanding of the global distribution of anammox bacteria and the ecological factors that affect their community structuring in diverse habitats.

Abstract: New native woodlands are typically created in a small and isolated configuration, potentially reducing their value as a resource for biodiversity. The use of ecological networks for habitat restoration and creation could be beneficial for woodland biodiversity. This approach is conceptualised as local‐ and landscape‐scale conservation actions designed to increase the area, quality, amount and connectivity of habitat types. However, there is limited evidence about the value of secondary woodlands and the relative or combined effects of network variables for woodland insects. Seventy‐eight woodland sites created in the last 160 years across England and Scotland were sampled for hoverflies (Diptera: Syrphidae) and craneflies (Diptera: Tipuloidea), using two Malaise net traps placed in the centre of each woodland. The diversity of insects supported by created woodland patches was analysed using measures of dissimilarity, and the relative direct and indirect effects of ecological network variables on their abundance and species richness were assessed using structural equation models. We found 27% of British woodland hoverfly species and 43% of British woodland cranefly species in the study sites, indicating that woodland insects are colonising created native woodlands, despite their fragmented nature. However, these species communities were highly variable across woodland patches. Landscape‐scale variables had no effect on woodland‐associated hoverflies or craneflies relative to local‐scale variables. Local‐scale variables relating to habitat quality (i.e. structural heterogeneity of trees and understorey cover) had the strongest influence on abundance and species richness. Synthesis and applications. To benefit woodland‐associated Diptera, woodland creation and restoration should maintain a focus on habitat quality. This should include active management to facilitate a diverse tree and understorey vegetation structure. Many woodlands in the UK are privately owned, and landowners should be encouraged to plant and actively manage their woodlands to increase structural heterogeneity and resources for woodland insects. [ABSTRACT FROM AUTHOR]

The Local Climate Zone (LCZ) scheme aims to provide an objective and standardized classification protocol for urban temperature studies in any city. The field observed temperature data from 12 selected LCZ sites in Nanjing, China, for the period from July to November 2016, was used to evaluate the LCZ scheme. The results here are the first to assess the LCZ scheme in a high-density city in mainland China. Distinct thermal differences among the LCZ sites provide preliminary evidence to support that the LCZ concept is applicable for urban temperature studies in cities of China. [ABSTRACT FROM AUTHOR]

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In ponderosa pine and mixed conifer ecosystems of the Southwestern US, regional-scale climate tends to synchronize fire years among study sites and increase fire extent or severity within a forest. At landscape scales (1–100 km 2 ), fire frequency and severity may also be influenced by local-scale differences in elevation and aspect, including fire barriers in rugged terrain. This study examines local-scale and regional controls of past fire regimes in three tributary watersheds of the San Juan Mountains of southwestern Colorado. In each watershed, we sampled fire-scarred trees and tree age structure and identified fire years and cohorts of post-fire tree recruitment. Fire frequency varied by aspect, and we observed the largest differences between the north- and south-facing aspects in the two largest basins. Fire severity was also different by aspect, with low-severity fire regimes on south-facing slopes and mixed-severity fire on north-facing slopes. The majority of fire years were unique, single-basin fires, indicating a lack of synchrony of fire years among basins, which we attributed to fire barriers and rugged terrain. We conducted Superposed Epoch Analysis (SEA) on two groups of fire years, to show average climate conditions before and during fire years. The first group were unique single-basin fires ( n = 27) and the second group included all years when synchronous fire burned in two or three basins ( n = 15). Both groups had significantly dry Palmer Drought Severity Index (PDSI) values during the fire year ( p < 0.01), while the second group also showed significantly wet conditions for two years prior to the fire year ( p < 0.01). Steep topography and fire barriers likely reduced the influence of regional climatic on the frequency and timing of fires for individual basins, though fires still burned during years of regional drought. Rugged terrain also contributed to asynchronous fire years among basins and longer fire return intervals compared with other ponderosa pine and mixed conifer forests in the region. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) spectroscopy was used to predict the soil organic carbon (SOC) contents at local scale in eleven target sites. For that, eight spectral libraries of different sizes (ranging from 3482 to 36 samples) were used to construct national, provincial and local scale models. Inaccurate predictions were obtained except when the largest national library was used to construct the model. We also obtained SOC predictions once the models were adapted to target sites characteristics. For the models’ adaptation, we used a two-step approach consisting on spiking (as first step) and extra-weighting (as second step). The effect of spiking was small in larger-sized models and high in smaller-sized models, whereas the effect of extra-weighting was small in smaller-sized models and large in larger-sized models. The very high accuracy obtained after models’ adaptation ( R 2 > 0.95; RPIQ > 5.48), regardless of the size of the spectral library, suggests that large spectral libraries are not needed for local scale SOC assessment. These results have important implications regarding the way that NIR spectroscopy can result highly effective for land management and how users can focus and organize the analytical efforts. [ABSTRACT FROM AUTHOR]

This paper described the variability of stream temperature, T s , and compared relationships between T s and air temperature, T a , at 10 sites along a 1.2 km reach in a 2 km 2 basin in New Jersey, USA, using Bayesian Hierarchical Regression. Mean daily mean T s was significantly cooler at two sites and significantly warmer at three sites relative to the mean daily T s for all sites combined. Seasonal daily mean T s showed the greatest variation between sites in the summer within the reach for both daily mean and daily maximum temperatures. Posterior distributions for slope parameters ( β j ) for regressions varied significantly by season and showed the greatest variation in summer. The strongest relationships occurred in autumn with β = 0 . 743 ± 0 . 019 ( β = 0 . 712 ± 0 . 022 ), and the weakest relationships occurred in the summer with β = 0 . 254 ± 0 . 030 ( β = 0 . 193 ± 0 . 039 ). Results support the conclusion that riparian shading impacts the effect of T a on T s , and that T s shows a stronger relationship with measured T a at sites in open areas that are more likely to have meteorologic conditions similar to bulk conditions.

The potential risk caused by the leakage of toxic and hazardous substances during air pollution accidents poses a great threat to local environmental safety, human heath, and even property security. Uncertainties and causalities are important components that should not be ignored in risk assessment. Compared with traditional non-probabilistic methods, Bayesian networks (BNs) are well suited to solving problems with high complexity and uncertainties. To utilize these advantages, a BN-based approach, coupled with diffusion simulation of risk substances, was proposed to estimate the risk of air pollution accidents in a probabilistic way at the local scale. This method was applied to analyze the risk levels of 24 risk sources and 24 risk subregions in Daya Bay, a national economic and technological development zone with a large petrochemical industry in Huizhou, Guangdong province. The results indicated that the Daya Bay area suffered a relatively low risk of accidental air pollution. Only five risk sources (20.8%) and two risk subregions (8.3%) were found to have high danger or risk. Ammonia, styrene, and sulfur dioxide were the most threatening substances in order. Acute exposure was the most sensitive factor, and made the highest contribution to risk level. This research provides an effective approach that can be used to characterize the air pollution accident risk quantitatively, probabilistically, and graphically. Probabilistic risk assessment can provide substantial support to local risk prevention, control, and emergency response for accidental air pollution, as well as to future risk management and policy decisions. [Display omitted] • A BN-based formal probabilistic approach is proposed for accidental air pollution risk analysis at the local scale. • Uncertainties and causalities in risk assessment are well expressed. • Dispersion models are introduced to enhance quantitative exposure estimation. • Daya Bay suffers a relatively low risk of accidental air pollution, acute exposure is the key driver of the risk level. • The results provide more detailed support to local accidental air pollution risk management. [ABSTRACT FROM AUTHOR]

Sky view factor (SVF), which is an indicator of urban canyon geometry, affects the surface energy balance, local air circulation, and outdoor thermal comfort. This study focused on a continuous and long-term meteorological observation system to investigate the effects of SVF on outdoor thermal conditions and physiological equivalent temperature (PET) in the central business district (CBD) of Beijing (which is located within Chaoyang District), specifically addressed current knowledge gaps for SVF-PET relationships in cities with typical continental/microthermal climates. An urban sub-domain scale model and the RayMan model were used to diagnose wind fields and to calculate SVF and long-term PET, respectively. Analytical results show that the extent of shading contributes to variations in thermal perception distribution. Highly shaded areas (SVF <0.3) typically exhibit less frequent hot conditions during summer, while enduring longer periods of cold discomfort in winter than moderately shaded areas (0.3< SVF <0.5) and slightly shaded areas (SVF >0.5), and vice versa. Because Beijing has a monsoon-influenced humid continental climate with hot summers and long, cold, windy, and dry winters, a design project that ideally provides moderate shading should be planned to balance hot discomfort in summer and cold discomfort in winter, which effectively prolongs the comfort periods in outdoor spaces throughout the entire year. This research indicate that climate zone characteristics, urban environmental conditions, and thermal comfort requirements of residents must be accounted for in local-scale scientific planning and design, i.e., for urban canyon streets and residential estates. [ABSTRACT FROM AUTHOR]

An advantage of trait-based approaches to ecology is the ability to predict the response of a species assemblage to environmental change through trait-environment relationships. Because species assemblages are also known to be affected by spatial processes, variation in community-level traits may be similarly affected by spatial structure. Furthermore, the importance of spatial structure may vary with changes to the environment. Using a dataset describing a local stream fish assemblage and environmental variables, we examine the relative contribution of environmental and spatial factors in explaining variation in community-level traits across seasons. We also test for any spatial structuring of community-level traits. For most traits, seasonal environmental change did not seem to alter the relative importance of environmental factors. Traits that did not vary consistently with environmental variables across seasons exhibited significant spatial structure. Overall, relationships between traits and environmental variables seemed to operate on a continuum with 'environmental traits' (those that were strongly correlated with environmental variables in response to environmental change) at one end to 'spatial traits' (those that did not correlate with environments, but exhibited spatial structure) at the other. We suggest that the distinction between these types of traits is important, as different modeling approaches would be appropriate in using community-level traits to predict the response of species assemblages to environmental change. [ABSTRACT FROM AUTHOR]

Abstract: As the pace of urbanization accelerates, the conservation of urban biodiversity emerges as a rising concern. Urban ecological research has revealed that some green areas in cities can harbor a rich diversity of species that can be enhanced by certain landscape- and local-scale structural planning variables. However, while most studies have been conducted in large greenspaces (e.g., parks, remnants), less effort was made to understand which variables influence biodiversity within small green patches and the efficiency of management practices has been seldom investigated. Here, we explore how management practices interplayed with landscape and structural variables to influence the diversity of plants, birds, butterflies and other pollinating insects in small public gardens (0.5–2.0ha) in the center of a large metropolis (Paris, France). Small public gardens hosted significant common biodiversity and the ones that employed a conservation program (i.e., differential management) supported a higher diversity of all taxa and less urbanophile communities of birds and butterflies. Local-scale and management variables were more important in enhancing biodiversity than landscape-scale variables. Specifically, lawns rich in wild plants attracted many pollinators and bird richness increased with tree cover. Pesticides had a negative effect on bird richness, while a higher diversity of habitats and soils (i.e. mulching, peat) increased the diversity of all four taxa. We also found that bird richness could serve as a reasonable surrogate for butterflies and other pollinators. Our results highlight how planning and managing public gardens in the center of a large metropolis can benefit biodiversity, regardless of spatial context. [Copyright &y& Elsevier]

Abstract: The atmospheric release of 131I and 137Cs in the early phase of the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident from March 12 to 14, 2011 was estimated by combining environmental data with atmospheric dispersion simulations under the assumption of a unit release rate (1 Bq h−1). For the simulation, WSPEEDI-II computer-based nuclear emergency response system was used. Major releases of 131I (>1015 Bq h−1) were estimated when air dose rates increased in FNPP1 during the afternoon on March 12 after the hydrogen explosion of Unit 1 and late at night on March 14. The high-concentration plumes discharged during these periods flowed to the northwest and south–southwest directions of FNPP1, respectively. These plumes caused a large amount of dry deposition on the ground surface along their routes. Overall, the spatial pattern of 137Cs and the increases in the air dose rates observed at the monitoring posts around FNPP1 were reproduced by WSPEEDI-II using estimated release rates. The simulation indicated that air dose rates significantly increased in the south–southwest region of FNPP1 by dry deposition of the high-concentration plume discharged from the night of March 14 to the morning of March 15. [Copyright &y& Elsevier]

With limited financial resources available for habitat restoration, information that ensures and/or accelerates success is needed to economize effort and maximize benefit. In the Central Valley of California USA, riparian habitat has been lost or degraded, contributing to the decline of riparian-associated birds and other wildlife. Active restoration of riparian plant communities in this region has been demonstrated to increase local population sizes and species diversity of landbirds. To evaluate factors related to variation in the rate at which bird abundance increased after restoration, we examined bird abundance as a function of local (restoration design elements) and landscape (proportion of riparian vegetation in the landscape and riparian patch density) metrics at 17 restoration projects within five project areas along the Sacramento River. We developed a priori model sets for seven species of birds and used an information theoretic approach to identify factors associated with the rate at which bird abundance increased after restoration. For six of seven species investigated, the model with the most support contained a variable for the amount of riparian forest in the surrounding landscape. Three of seven bird species were positively correlated with the number of tree species planted and three of seven were positively correlated with the planting densities of particular tree species. Our results indicate that restoration success can be enhanced by selecting sites near existing riparian habitat and planting multiple tree species. Hence, given limited resources, efforts to restore riparian habitat for birds should focus on landscape-scale site selection in areas with high proportions of existing riparian vegetation. [ABSTRACT FROM AUTHOR]

Abstract: As the amount of urbanization in the landscape surrounding a riparian zone increases, local riparian vegetation structure and composition change in complex ways. The impact of increasing urbanization on birds in and around riparian zones will depend on their differential sensitivity to local- versus landscape-scale habitat variation. Thus, our principal objective was to determine which spatial scale has a greater association with the distribution of each bird species using riparian corridors in a landscape mosaic comprised of anthropogenic land uses and undeveloped native shrublands in coastal southern California. We surveyed 137 points in riparian vegetation along an urbanization gradient, and used logistic regression and information theory to select best supported models describing the distribution of each of 52 bird species. Models based only on local-scale vegetation variables were best supported for 19 species, whereas landscape-scale (amount of urbanization within a 1000-m radius) models were best supported for 13. Ten species were best described by models combining local- and landscape-scale variables, and 10 had no well-supported models. Within guilds, woodland and riparian-dependent species appeared to respond to local vegetation variables whereas shrubland species appeared more sensitive to landscape context. Likewise, insectivores were more likely to be associated with variation in local-scale variables. In contrast to other studies, Neotropical migrants were not sensitive to increasing urbanization. Provided that local vegetation remains in good condition, our results suggest that riparian bird species may persist even in areas with extensive urbanization. [Copyright &y& Elsevier]

Abstract: A carbon budget was calculated for Tompkins County, NY, a semi-rural upstate county with a population density of 78pp/km2. The costs and potential for several carbon mitigation options were analyzed in four categories: terrestrial C sequestration, local power generation, transportation, and energy end-use efficiency. This study outlines a methodology for conducting this type of local-scale analysis, including sources and calculations adaptable to different localities. Effective carbon mitigation strategies for this county based on costs/MgC and maximum potential include reforestation of abandoned agricultural lands, biomass production for residential heating and co-firing in coal power plants, changes in personal behavior related to transportation (e.g., public transportation), installation of residential energy efficient products such as programmable thermostats or compact fluorescent light bulbs, and development of local wind power. The total county emissions are about 340GgC/year, with biomass sequestration rates of 121GgC/year. The potential for mitigation, assuming full market penetration, amounts to about 234GgC/year (69%), with 100GgC/year (29%) at no net cost to the consumer. The development of local-scale C mitigation plans based on this sort of model of analysis is feasible and would be useful for guiding investments in climate change prevention. [Copyright &y& Elsevier]

Investigation of the relationships between socioeconomic factors and water-related disasters, such as floods, is rather complex. The general practice is to undertake a qualitative analysis of the impact of socioeconomic factors on economic loss in disasters, while climate and structural impacts are investigated quantitatively. As such, an integrated approach is timely for understanding socioeconomic influences on economic loss due to floods. This paper is an attempt to understand the influence of different factors on economic loss, in different types of floods, among different economic groups, using a quantitative approach. Data was collected using a questionnaire survey delivered to randomly selected households in Rathnapura, Sri Lanka, in September 2017. Path analysis was used to analyze the influence of socioeconomic status on economic loss due to floods, using an effective sample of 231 households after subdividing the sample into poor and non-poor subcategories, based on socioeconomic condition. The results suggest that flood characteristics and household income level have a direct impact on economic loss in severe floods for both economic groups, with more significant impacts among poor households. Even for minor floods, inundation depth is the most significant factor affecting relative loss, irrespective of the economic group. Further, the absolute loss difference between poor and non-poor households is 48% of the loss experienced by non-poor households in severe floods, and 10% of the loss due to minor floods. These results indicate that severe floods increase the economic gap between the poor and non-poor cohorts. Through this analysis, it is concluded that floods exacerbate the economic gap between poor and non-poor communities, while the factors affecting economic loss due to floods differ among the different economic groups. [ABSTRACT FROM AUTHOR]

The discovery of anaerobic ammonia oxidation (anammox) expanded our knowledge on the microbial nitrogen cycle. Previous studies report that anammox bacteria are distributed in a wide range of habitats and plays significant roles in the global nitrogen cycle. However, most studies focus only on individual ecosystems or datasets from public databases. To date, our understanding of how anammox bacteria respond to environmental properties and are distributed in different habitats on a global scale, remain unclear. To explore the global distribution of anammox bacteria, samples were collected from different habitats at different locations globally, including wetlands, drylands, groundwater aquifers and snow from 10 countries across six continents. We then used high-throughput amplicon sequencing targeting the functional gene hydrazine synthase (HZS) and generated community profiles. Results showed that Candidatus Brocadia is detected as the dominant genus on a global scale, accounting for 80.0% to 99.9% of the retrieved sequences in different habitats. The Jettenia-like sequences were the second most abundant group, accounting for no more than 19.9% of the retrieved sequences in all sites. The samples in drylands, wetlands and groundwater aquifers showed similar community composition and diversity, with the snow samples being the most different. Deterministic processes seem stronger in regulating the community composition of anammox bacteria, which is supported by the higher proportion explained by local-scale factors. Groundwater aquifers showed high gene abundance and the most complex co-occurrence network among the four habitat types, suggesting that it might be the preferred habitat of anammox bacteria. There is little competition between anammox bacterial species based on co-occurrence analysis. Hence, we could infer that environmental factors such as anaerobic and stable conditions, instead of substrate limitations, may be vital factors determining the anammox bacteria community. These results provide a better understanding of the global distribution of anammox bacteria and the ecological factors that affect their community structuring in diverse habitats., (Copyright © 2019 Wang, Xu, Wang, Ye and Zhu.)