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Soil protists have vital roles as major microbiome predators in soil functioning and plant performance. Protists are also suggested to be the most responsive microbial group to external changes, such as anthropogenic land use types. While protists were long used as models for biogeography such as to investigate if 'everything is everywhere' among microbes, their biogeography at the taxonomic level has never been explored in depth at the continental scale and linked to anthropogenic drivers. Here we evaluated how land-use types affect the diversity and structure of soil protist communities across 885 locations in Europe based on the European Commission's Land Use and Coverage Area frame Survey (LUCAS). We observed higher α-diversity of soil protists but lower community structure dissimilarity (β-diversity) in croplands compared with woodlands, with grasslands in an intermediate position. The diversity of protist groups with a broader spatial niche was higher in croplands, whereas taxa with a narrower niche increased in woodlands. The importance of climate factors on α-diversity variations reduced as land use intensity increased, but the opposite trend was observed for the effect of soil properties. Our study suggests that there is an interaction between land use type, environmental effects, and spatial niche attributes of soil protist groups, highlighting the importance of land-use type on the dynamics of protist communities. • Land use intensity affect α- and β-diversity of soil protist groups in an opposite manner. • There were interactions between environmental effects and land use types on α-diversity. • Generalist protists tend to be more diverse in more intensive land use types. [ABSTRACT FROM AUTHOR]

• Land use influenced bacteria in lake inflows, enabling downstream consequences. • Standard fecal indicators are insufficient to detect downstream effects from land use. • Associated with inflows and land use, Legionella exemplifies downstream effects. • Reliable access to clean water needs consideration of indirect downstream effects. • This framework can assess new sources in case of drinking water disturbances. Intensified land use can disturb water quality, potentially increasing the abundance of bacterial pathogens, threatening public access to clean water. This threat involves both direct contamination of faecal bacteria as well as indirect factors, such as disturbed water chemistry and microbiota, which can lead to contamination. While direct contamination has been well described, the impact of indirect factors is less explored, despite the potential of severe downstream consequences on water supply. To assess direct and indirect downstream effects of buildings, farms, pastures and fields on potential water sources, we studied five Swedish lakes and their inflows. We analysed a total of 160 samples in a gradient of anthropogenic activity spanning four time points, including faecal and water-quality indicators. Through species distribution modelling, Random Forest and network analysis using 16S rRNA amplicon sequencing data, our findings highlight that land use indirectly impacts lakes via inflows. Land use impacted approximately one third of inflow microbiota taxa, in turn impacting ∼20–50 % of lake taxa. Indirect effects via inflows were also suggested by causal links between e.g. water colour and lake bacterial taxa, where this influenced the abundance of several freshwater bacteria, such as Polynucleobacter and Limnohabitans. However, it was not possible to identify direct effects on the lakes based on analysis of physiochemical- or microbial parameters. To avoid potential downstream consequences on water supply, it is thus important to consider possible indirect effects from upstream land use and inflows, even when no direct effects can be observed on lakes. Legionella (a genus containing bacterial pathogens) illustrated potential consequences, since the genus was particularly abundant in inflows and was shown to increase by the presence of pastures, fields, and farms. The approach presented here could be used to assess the suitability of lakes as alternative raw water sources or help to mitigate contaminations in important water catchments. Continued broad investigations of stressors on the microbial network can identify indirect effects, avoid enrichment of pathogens, and help secure water accessibility. [Display omitted] [ABSTRACT FROM AUTHOR]

The ocean is the ultimate sink for all pollutants, rivers are important channels for land-based pollutants to enter the oceans. Riverine transport of polycyclic aromatic hydrocarbons (PAHs) to coastal seas in China poses environmental threats. This study examined the spatial and temporal distribution of PAHs in coastal rivers in Yancheng City in Jiangsu Province of China, with the aim of identifying their likely sources, concentrations, and influencing factors. Surface sediments were taken from the Xinyanggang River (XYR) and the Sheyang River (SYR). The concentrations of Ʃ 16 PAHs in river sediments were measured on average 477.05 ng/g dry weight (dw), with values varying from 2.18 to 6351.42 ng/g, indicating a moderate pollution level, with a dominance of high molecular weight (HMW) PAHs. The XYR exhibited significantly higher PAHs concentrations compared to the SYR. The key sources of PAHs were vehicle emissions (47.87%), coal and natural gas combustion (35.07%). Geographically weighted regression and redundancy analysis linked PAHs pollution to distinct land use patterns and socioeconomic indicators, highlighting urban land as the major contributor, driven by high urbanization and industrialization (70.91%). In XYR, industrial activities and transport emissions were major contributors, while in SYR, agricultural activities predominantly influenced PAHs pollution. Urgent mitigation strategies are needed to reduce PAHs pollution in river sediments, mitigating ecological and human risks associated with these contaminants. [Display omitted] • Xinyanggang River was noticed to be the hotspots of PAHs pollution. • Vehicle emissions are the key sources of PAHs pollution in the river sediment. • Urban land strongly correlates with PAHs pollution then agriculture land. • Mitigations strategies and urgent policies are needed to reduce the PAHs pollution. [ABSTRACT FROM AUTHOR]

Microorganisms are important transporters of mass and energy under the influence of external disturbances. However, the bacterial communities in the sediment of the Yangtze River and the influence of the synergistic effect of geographical characteristics and anthropogenic activities remain poorly understood. To analyze the bacterial community compositions and determine the driving factors that cause the niche segregation of the bacterial assembly, samples located along the Yangtze River were analyzed using Illumina Miseq sequencing. Based on the results, Proteobacteria, Bacteroidetes, Actinobacteria, Acidobacteria, and Chloroflexi were identified as dominant phyla, and Alphaproteobacteria was the most dominant subdivision. The bacterial diversity was most significantly correlated with elevation (p < 0.01), followed by urbanization rate (p < 0.01), and organic matter (p < 0.05). A decreasing trend of bacterial diversity was found along the elevation and a threshold of 400 masl was observed with regard to the bacterial richness and community compositions in response to elevation gradient. Above 400 masl, the bacterial richness was closely associated with elevation gradient, followed by total phosphorus and total nitrogen, while below 400 masl elevation, urbanization rate and Cu were dominant variables. Redundancy analysis indicated that bacterial community compositions were mostly related to the input of organic matter (20.0%, p = 0.001), followed by elevation (10.4%, p = 0.003), urbanization rate (9.0%, p = 0.017) and Pb (9.5%, p = 0.026). Distance-decay correlation analysis also showed that the variations of bacterial community structures were significantly positively correlated with elevation and organic matter. Based on the results of the meta-community, in general, the altitudinal gradient exerted a more notable influence than anthropogenic disturbance on bacterial communities. However, increased concentrated anthropogenic exploitation and interference might contribute more to deterministic processes driven by competition and niche differentiation of bacterial community structures in the sediment of the Yangtze River along the elevation gradient. [ABSTRACT FROM AUTHOR]

We investigate the effects of spatial changes in environmental conditions and anthropogenic influences on larval fish communities in two tropical estuaries with varying levels of human impact. Our findings revealed a distinct structure of larval fish assemblages between the two estuaries located in northeastern Brazil, and we observed that eutrophication, characterized by high concentrations of nutrients, had adverse effects on the abundance and richness of larval fish assemblages. Additionally, we observed that a decrease in rainfall had an impact on larval fish assemblages, particularly during the dry season, when intermittent upstream rivers lead to changes in salinity and species composition within the estuaries. This study contributed to evaluating the community descriptors of two tropical estuaries under different levels of human influence, providing insights into the vulnerability of larval fish assemblages to climate change, specifically in relation to human influences and hypersalinity and the effects of marinization in shallow tropical estuaries in this region. [Display omitted] • Eutrophication had adverse effects on the abundance and richness of larval fish assemblages. • Decrease in rainfall had an impact on larval fish assemblages. • Differences in larval fish assemblages occur due to variations in habitat quality. • Nutrient pollution can have an inverse effect on the richness and abundance of species. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau is a critical ecosystem that sensitively responds to ongoing glacier shrinkage and permafrost thaw. Dissolved organic matter (DOM) in Tibetan Alpine rivers plays pivotal roles in the biogeochemical cycling of elements and nutrients at regional and even global scales, impacting water quality, downstream environments, and climate. However, little is known about the characteristics and dynamics of DOM in these watersheds. We investigated five major Himalayan rivers in the southern Tibetan Plateau, utilizing bulk dissolved organic carbon (DOC), optical properties, and molecular formulas. We found extremely low DOC and fluorescent DOM (FDOM) levels in the rivers (average DOC: 0.25–0.87 mg L−1, FDOM: 0.02–0.05 RU) with a highly degraded molecular signature, which was enriched with heteroatomic molecular formulas (S-containing: 58–72%, N-containing: 61–86%) and condensed aromatics (31–39% vs. ∼11% in world major rivers). Further, 81–99% of the condensed aromatics was identified as dissolved black nitrogen (DBN) with multiple nitrogen atoms, typical for grassy biomass combustion. The findings highlighted potentially fast DOM remineralization leading to the release of CO 2 and enriched apparently anthropogenic condensed aromatics and heteroatomic formulas in what have been considered pristine Tibetan rivers. These findings should be considered in future biogeochemical models and ecosystem management. Image 1 • DOM characteristics were explored in Alpine rivers and lakes in the HTP. • A suite of potential sources of DOM in the Alpine watersheds has been discussed. • Extremely low relic DOC and fluorescent DOM levels were observed in Tibetan rivers. • Highly degraded molecular signature from anthropocentric origins were found. • Most condensed aromatics was suggested from grassy biomass combustion. [ABSTRACT FROM AUTHOR]

This study investigates the long-term morphological pattern of the Hsinchu coast in northwestern Taiwan using three different methods: long-term isobath and shoreline change analysis, bathymetric volume change analysis, and the empirical orthogonal function (EOF) method. Our objectives include analyzing and understanding the effects of anthropogenic structures, natural processes, and their combined impacts on coastal morphological change. The shoreline analysis and bathymetric volume analysis briefly reveal that the morphological pattern of Hsinchu coast. Then, EOF analysis is applied to identify the dominant impact factors affecting the coastal morphology near the harbor, determine the weights of the impact factors, and infer the impact range of anthropogenic structures. Moreover, the EOF analysis is divided into two-time segments—namely, the periods 2005–2010 and 2017–2021—based on different bathymetric surveys and the corresponding values of impact factors. The primary and secondary EOF modes are strongly linked to the "interaction between wave and structure" and "interaction between river discharges and structure", respectively. The spatial components of the EOF modes demonstrate that the impact range influenced by river discharges was mainly located in the northern part of the harbor, while the minimum impact range of the structures on coastal morphological interaction changes under natural factors was 3.5 km south of Hsinchu Fishing Harbor. • The morphological patterns of the Hsinchu coast over a span of two decades were characterized in this paper. • The findings of the EOF analysis were utilized to identify the impact factors and determine the corresponding weights. • The findings can inform the development of effective strategies for coastal management. [ABSTRACT FROM AUTHOR]

Due to increasing anthropogenic impacts on deep-sea hydrothermal vent ecosystems, it is essential to understand population structure and maintenance through larval recruitment and recovery of vent faunas after disturbances. In this study, we quantified vent animal recruitment in the Okinawa Trough, in the western Pacific Ocean. This is the first study to investigate recruitment patterns at a man-made hydrothermal vent. Colonization plates were deployed at three sites. Site 1 manifested new hydrothermal shimmering with small chimneys, white bacterial mats, and some alvinocaridid shrimp that arrived after drilling. Site 2 showed no evidence of newly arrived foundation species after drilling, and Site 3 had pre-existing animal communities in the vicinity of the new vent. Twenty-two months after deployment, colonization plates were retrieved and recruited animals were inventoried. Species composition and abundance differed among sites, but relatively high similarity in species composition was observed at Sites 1 and 3, though not at Site 2. Newly established communities on the plates at Sites 1 and 2 (no pre-existing fauna) showed lower species richness and abundance than at Site 3. Differences in abundance and size-frequency distributions of major recruits on the plates (i.e. Lepetodrilus nux , Bathymodiolus spp.) suggest the importance of reproductive and early life-history characteristics in spatial variability of recruitment. Lepetodrilus nux populations established on the plates at Site 1 showed high genetic connectivity. These results illustrate the importance of localized recruitment, which may have a significant impact on sustainability of vent faunal populations, despite the existence of regional metapopulations. [ABSTRACT FROM AUTHOR]

Understanding the anthropogenic effects on the Sefidrud delta, the concentration of six metals (Cr, Co, Cu, Ni, Pb and Zn) was measured in two sites included the old Sefidrud delta (Amirabad, 23 samples) and the new Sefidrud delta (Kiashahr, 24 samples). Geoaccumulation Index (I geo ), Enrichment Factor (EF), Contamination Factor (CF) and Pollution Load Index (PLI) were used to determine the metal pollution in all sediment samples. Although the EF, I geo , CF and PLI results in the old delta indicate no significant pollution, sediment samples in the new delta show a considerable pollution. Since the sediment source and the lithology of the Sefidrud River drainage basin did not change in the past 500 years, the metal pollution in the new delta must be from anthropogenic sources. [ABSTRACT FROM AUTHOR]

Anthropogenic water management has extensively altered the world's river systems through impoundments and channel diversions to meet the human's need for water, energy and transportation. To illuminate the effect of such activities on the environment, this study describes the impact of the installation of the Kárahnjúkar Dam in Eastern Iceland on the transport of riverine dissolved- and particulate material to the ocean by the Jökulsá á Dal and the Lagarfljót rivers. This dam, completed in 2007, collects water into the 2.2 km 3 Hálslón reservoir and diverts water from the glacial Jökulsá á Dal river into the partially glaciated Lagarfljót lagoon via a headrace tunnel. The impact of the damming was evaluated by sampling water from both the Jökulsá á Dal and the Lagarfljót rivers over a 15 year period spanning from 1998 to 2013. The annual flux of most dissolved elements increased substantially due to the damming. The fluxes of dissolved Zn, Al, Co, Ti and Fe increased most by damming; these fluxes increased by 46–391%. These differences can be attributed to changed saturation states of common secondary minerals in the Jökulsá á Dal due to reduced discharge, increased residence time and dissolution of suspended material, and, to a lesser degree, reduced photosynthesis due to less transparency in the Lagarfljót lagoon. The removal of particulate material and thus decreasing adsorption potential in the Jökulsá á Dal is the likely reason for the Fe flux increase. In contrast, approximately 85% of the original riverine transported mass of particulate material is trapped by the dam; that which passes tends to be relatively fine grained, increasing the average specific surface area of that which continues to flow towards the ocean. Consequently, the particulate geometric surface area flux is decreased by only 50% due to the damming. The blooming of silica diatoms during the spring consumes dissolved silica from the coastal waters until it becomes depleted; making the riverine spring dissolved silica flux an important source of this nutrient. Despite extensive riverine flux changes due to the Kárahnjúkar dam construction, the total spring dissolved silica flux increased, and thus so too the potential for a silica diatom spring bloom in the coastal waters. This is likely because the spring flux is dominated by snow melting downstream of the dam. [ABSTRACT FROM AUTHOR]

We place a 2.5% limit on the anthropogenic contribution to the modern abundance of 81 Kr/Kr in the atmosphere at the 90% confidence level. Due to its simple production and transport in the terrestrial environment, 81 Kr (half-life = 230,000 years) is an ideal tracer for old water and ice with mean residence times in the range of 10 5 –10 6 years. In recent years, 81 Kr-dating has been made available to the earth science community thanks to the development of Atom Trap Trace Analysis (ATTA), a laser-based atom counting technique. Further upgrades and improvements to the ATTA technique now allow us to demonstrate 81 Kr/Kr measurements with relative uncertainties of 1% and place this new limit on anthropogenic 81 Kr. As a result of this limit, we have removed a potential systematic constraint for 81 Kr-dating. [ABSTRACT FROM AUTHOR]

[Display omitted] • A framework was developed to quantify temperature-greenness mismatch at large scale. • Most greenness isolines lag behind or move inversely to the temperature isolines. • The temperature-greenness mismatch was more pervasive in forests than in grass. • Human activity played an important role in temperature-greenness mismatch of China. Warming is projected to increase the greenness of vegetation and lead to geographic shifts in vegetation isolines across China. However, it is unclear whether the shift of greenness isolines can keep pace with that of temperature isolines because vegetation activity is always limited by resource availability and relatively slow acclimation mechanisms. In addition, how natural and anthropogenic factors affect this mismatch is poorly understood. Based on remote sensing observations over the last two decades (2000–2020), we systematically evaluated how vegetation greenness shifts respond to warming trends in China. The result showed a widespread mismatch between temperature and greenness. 74 % of the area showed isolines of greenness lag behind or move in the opposite direction to the isolines of temperature. We also found the temperature-greenness mismatch is strongly determined by elevation, slope, vegetation type, and human activity. The magnitude of the mismatch decreased inversely with slope and elevation but increased when human activity increased. The mean magnitude of mismatch between temperature and greenness in velocity was the greatest for deciduous forest (0.45 km/year), followed by grass, shrubs, and evergreen forest. This systematic analysis of the temperature-greenness mismatch has important implications for the sustainable management of vegetation under climate change. Our study underscored the importance of understanding the role of topography, vegetation, and human activity when studying the temperature-greenness mismatch. [ABSTRACT FROM AUTHOR]

The increasing pressure on water resources demands integrated and multidisciplinary approaches to address environmental, scientific, and social issues related to water availability in watersheds. In large watersheds, many factors control hydrologic processes, requiring the application of a methodology able to describe water dynamics in complex situations. This study uses stable isotope (2H and 18O) modeling to characterize the groundwater contribution in an area of heterogeneous hydrogeological framework and advanced anthropization, located in the Piracicaba-Capivari-Jundiaí (PCJ) and Tietê-Jacaré (TJ) water management units – central-eastern portion of the state of São Paulo, Brazil. Groundwater dynamics are controlled by the direct interaction of the rainfall regime with hydrogeological domains. The modeling in this study indicates that some 60–80% of the total streamflow volume comes from groundwater. However, in the crystalline domain, the aquifer capacity for surplus water storage is smaller, increasing the importance of rainfall for generating direct runoff and maintaining the streamflow. For this characteristic, the PCJ unit is more dependent on surface water and vulnerable to prolonged droughts. On the other hand, in the sedimentary areas, the contribution of groundwater discharge is around 80%, showing that the aquifer storage capacity guarantees homogenization of the discharge throughout the year, and ensures water security in drought periods. It is concluded that the successful application of stable isotope modeling in large basins. The method, combined with others already established, can add a more dynamic and sensitive set of information for understanding hydrological processes in complex hydrographic basins, with heterogeneous hydrogeological structures and the effects of anthropic action. [Display omitted] • Assess the contribution of groundwater discharges using stable isotopes (H and O) in basins with heterogeneous hydrogeology. • Know the analysis capacity of stable isotopes in large watersheds whit different intensities of anthropogenic activities. • Propose the use of stable isotopes as an additional tool for the comprehension of hydrodynamics in the complex watershed. [ABSTRACT FROM AUTHOR]

• Sediment dynamics around buildings are included in a cellular automaton model. • Simulated deposition and erosion patterns show good agreement with field experiments. • Building effects interact with local bedform dynamics, and can affect dune shape, growth and migration. Buildings affect aeolian sediment transport and bedform development in sandy environments. Cellular automaton (CA) models have, however, only been used to simulate natural bedform dynamics. This study extends a well-known aeolian CA model to include sediment dynamics around buildings, and uses this model to explore the interaction of building-induced deposition and erosion with natural bedform dynamics. New CA rules are introduced to represent acceleration, deceleration and sideward transport of sediment around obstacles. The simulated deposition and erosion patterns show good agreement with field experiments. The model reproduces the shape and location of the morphological pattern around a single building, and effects of building spacing on this pattern for building groups. Model results further demonstrate that building-induced effects interact with local bedform dynamics and can alter the shape, growth and migration of sand dunes. [ABSTRACT FROM AUTHOR]

Interspecific competition between large carnivores is not well understood due to the complexity of carnivore guild dynamics and the array of ecological and human factors affecting them. The loss of a carnivore guild's dominant species can therefore provide considerable insights. We evaluated spotted hyaena density and demography from Zambia's Liuwa Plain National Park, a recovering ecosystem where the hyaena's main competitor, the African lion, was severely reduced to 3–5 animals. Using data from 233 individuals in five clans and mark-resight robust design models we estimated population size, density, age and sex-specific annual survival rates for the hyaena population from 2010 to 2013 and tested for the effect of human settlements, prey density, competition with lions and hyaena clan size on mean hyaena survival. We estimated a minimum density of 0.13 hyaenas/km 2 and maximum density of 0.52 hyaenas/km 2 . Density fluctuated with seasonal migrations of the main prey species, the blue wildebeest. Mean annual survival across all age classes was 0.93 (95%CI: 0.79–0.99). With high survival rates across all sex and age classes, we found no detectable effects of ecological or anthropogenic factors on survival. These results suggest that the combination of abundant prey, weak human-carnivore conflict, and weak competition from lions provide very favourable conditions for hyaena survival. Additional investigations of hyaena demography concurrent with lion population recovery efforts can provide considerable insights into the dynamics of carnivore competition and predation in African savannahs and the human and ecological factors affecting them. [ABSTRACT FROM AUTHOR]

Summary River ice is principally controlled by atmospheric conditions, especially temperature, so these records provide useful information on the climate in general. A more than 130-year-time-series of ice-on and ice-off, and freeze-up and break-up dates was analysed from 4 selected hydrological stations along the lower course of the River Drava since the beginning of river ice observations the start- and end-dates of ice phenomena on Drava River have displayed a significant trend. Freeze-up dates have shifted to ∼9 days later, and break-up dates to ∼10 days earlier. A similar trend is present in the dates of ice-on and ice-off; these dates have shifted to ∼23 days later and ∼17 days earlier per 100 years on average. These changes have resulted in a pronounced reduction in the ice-covered and ice-affected seasons, too. The duration of ice-cover has decreased by ∼14 days and the total number of ice-affected days has decreased by ∼31 days over a century on average on the lower course of the Drava. Interannual variability was compared to local and regional instrumental temperature records. The strongest correlation was found between ice-off and January–February mean temperatures ( r = 0.81, p < 0.05), and between the total number of icy days and the mean winter temperature ( r = 0.88, p < 0.05). Statistical evidence indicated, however, that the subdued climate control from the 1970s is probably due to anthropogenic intervention in the upper course (e.g. reservoir construction, hydropower management). Spatial correlation analysis revealed that the temperature signal carried by the river ice records of the Drava prior to the anthropogenic disturbance seems to be a powerful proxy for the winter temperature of Central Europe. [ABSTRACT FROM AUTHOR]

The St Lucia Estuary is the largest estuarine lake in Africa and due to anthropogenic activities it has since the 1950s been kept isolated from its main source of freshwater, the Mfolozi River. Stakeholders are increasingly calling for a full reconnection of the historical linkage in order to initiate system restoration. Studies conducted to test the effects of turbidity on the copepod Acartiella natalensis and the mysid Mesopodopsis africana have shown that turbidity reduces the fitness of these species. The turbidity tolerance of the dominant copepod Pseudodiaptomus stuhlmanni has not yet been documented. The aim of this study was to determine the effects of turbidity on the feeding, respiration and mortality rates of P. stuhlmanni . Although chlorophyll a and phaeopigment consumption was negatively affected by inorganic silt, the use of natural silt resulted in more variable trends. In contrast, a positive relationship was found between total organic carbon (TOC) consumption and turbidity. The high ingestion rates in the highest turbidity treatments of the TOC experiments are attributed to gut loading of organically-enriched silt. High turbidity also resulted in increased respiration rates of P. stuhlmanni , highlighting the energetic demand of turbid environments. Compared with other previously studied St Lucia zooplankters, P. stuhlmanni appears to be relatively tolerant of high turbidity. However, as the overall effect on this species is also negative, it is concluded that the St Lucia Estuary needs to be protected from excessive silt inputs if its ecological integrity is to be sustained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cryoconite dissolved organic matter was different across the Tibetan Plateau. • Anthropogenic, microbial activities and plant cover caused the spatial distribution. • Anthropogenically and terrestrial DOM accumulated more in the southern cryoconite. • More labile organic components were exported to downstream from southern glacier. A large amount of dissolved organic matter (DOM) is stored in glacier ecosystems, which is crucial for downstream oligotrophic aquatic ecosystems during glacier melting. However, knowledge about their spatial differences in glacier ecosystems on the Tibetan Plateau (TP) is limited. We qualitatively and quantitatively analyzed the DOM in snow, ice, cryoconite, and glacier-fed streams in five glaciers in the central and southern TP using ultra-high-resolution mass spectrometry. Our results revealed that there were no significant differences in DOM concentrations or composition between the central and southern TP glaciers in snow and ice samples. However, the southern cryoconite contained significantly higher relative intensities of carbohydrate-, lignin-, tannin-, and condensed aromatic-like compounds and lower intensities of lipid-like compounds than the central cryoconite. In addition, the DOM molecules sustained in the cryoconite of the southern glacier were predominantly classified as condensed aromatic-like compounds, whereas those of the central TP glaciers were classified as lignin-like compounds. Except different terrestrial input, the network analysis and backward trajectory revealed that different bacterial composition and anthropogenic inputs caused this difference. Higher forest cover leaded to higher relative intensities of lignin- and tannin- DOM in the southern cryoconite than the central cryoconite. Sixty-six operational taxonomic units (OTUs) were associated with the degradation of lipid-, proteins/amino sugar- and lignin-like components which showed significantly higher relative abundance in the southern cryoconite than the central cryoconite. More anthropogenic inputs brought by the India monsoon affect the carbohydrate- and condensed aromatic-like compounds in the southern cryoconite. DOM exported into glacial streams of the central TP glaciers was dominated by tannin- and condensed aromatic-like compounds, whereas more labile components were discharged from the southern TP glacier. Our study provides new insights on the glacier DOM composition in and exported from different glaciers in the face of changing climate. [ABSTRACT FROM AUTHOR]

Inter-annual trends in terrestrial water storage (TWS) were extracted from monthly (01/2003-09/2012) Gravity Recovery and Climate Experiment (GRACE) data acquired over Africa and correlated (in a geographic information system [GIS] environment) with relevant temporal remote sensing, geologic, and hydrologic datasets. Findings include the following: (1) large sectors of Africa are undergoing statistically significant TWS variations (+ 44 mm/yr to - 15 mm/yr) due to natural and anthropogenic causes; (2) warming of the tropical Atlantic Ocean apparently intensified Atlantic monsoons and increased precipitation and TWS over western and central Africa; (3) warming in the central Indian Ocean decreased precipitation and TWS over eastern Africa; (4) the high frequency of flooding events increased TWS over the Zambezi and Okavango basins; (5) extraction of fossil groundwater decreased TWS over the Saharan aquifers; (6) deforestation decreased TWS in three subbasins (Ubangi, Congo, and Sangha) of the Congo River Basin; and (7) the construction of dams increased TWS in the Blue Nile and Atbara subbasins. Given the 10 years of monthly GRACE data acquired on the subbasin scale across the globe, as well as the plans underway for deployment of a GRACE-FO and GRACE-II, using GRACE-derived TWS data should be considered an alternative, viable index for measuring temporal and spatial variations in water availability. [ABSTRACT FROM AUTHOR]

The differences in the spatial pattern of column carbon monoxide (CO) and in-situ measured near-surface CO over Bay of Bengal (BoB) during winter were examined in the light of vertical distribution of CO as retrieved from MOPITT (Measurements Of Pollution In The Troposphere) on board Terra spacecraft. The column CO showed relatively high values over southern-BoB whereas the near-surface CO showed low mixing ratio indicating the existence of significant amount of CO at higher altitudes. The vertical profiles of CO over the BoB region retrieved from MOPITT exhibit a high altitude peak around ~9 km altitude region. The role of water vapour and convective activity/vertical updrafts in establishing the observed vertical profile of CO was investigated. It is found that CO got uplifted to the higher altitude due to updrafts and water vapour caused depletion of CO at lower altitudes which appeared as an apparent high in CO mixing ratio at higher altitude relative to that over lower altitude. The role of water vapour in the destruction of CO was confirmed by box model simulations. Airmass back-trajectory analysis showed that the long range transport from lower troposphere/boundary layer was also partially responsible for higher mixing ratios at higher altitude. In addition, a comparison of in-situ measured near-surface CO and those retrieved from MOPITT using retrieval algorithm Versions 4 and 5 showed that the points of discrepancy have reduced in the Version 5. Biomass burning and anthropogenic activities taking place over the Myanmar landmass was found to be responsible for the hot spots of near-surface-CO over the northeast-BoB. [ABSTRACT FROM AUTHOR]

Numerous estuaries of the world have been strongly modified by human activities. These interferences can make great adjustments of not only sediment transport processes, but also the collective behavior of the estuary. This paper provides a typical case of a heavily modified coastal plain estuary of Sheyang on the China coast, where a sluice barrage was built in 1956 to stop the intrusions of storm surges and saline water. Four sets of instrumented tripods were simultaneously deployed along a cross-shore transect to continuously observe near-bed flow currents and sediment transport. The in-situ surveys lasted over a spring and neap tide cycle when a strong wind event occurred in the neap tide. Comparisons of flows and sediment transport between tide-dominated and wind-dominated conditions demonstrated the important role of episodic wind events in flows and sediment transport. The wind-induced currents, bottom stresses, and sediment transport rates were significantly greater when wind was present than corresponding quantities induced by the tides. The long-shore sediment transport induced by winds exceeds the cross-shore component, especially near the river mouth bar. These results indicate the noticeable importance of wave-dominated coastal processes in shaping topographic features. A regime shift of estuarine evolution under highly intense human forcing occurs from fluvial to marine processes. This finding suggests that the management strategy of the estuarine system should focus on the restoration of estuarine processes, rather than the present focus on inhibition of marine dynamics. [ABSTRACT FROM AUTHOR]

Abstract: Oil and gas platforms from Sergipe–Alagoas Basin located in the northeastern region of Brazil do not discharge produced water. However, those platforms can be a potential source of contaminants to the marine environment due to their producing activities. In this study, sediment samples were collected in the vicinity of two offshore oil and gas platforms located in Sergipe–Alagoas Basin (PCM-9 and PGA-1) to evaluate the source and levels of hydrocarbons and trace elements (As, Fe, Al, Ti, Cu, Cd, Zn, Pb, Ni, Mn, Ba, V, Cr and Hg). Also, the potential impact of those platforms on the sediment quality was investigated. Polycyclic aromatic hydrocarbons diagnostic ratios observed in the sediment samples indicated hydrocarbons from pyrogenic source, specifically from biomass combustion. Trace elements As, Cd and Ba recorded concentrations higher than Threshold Effect Levels (TEL) in the sediment nearby the platforms. Also, there was evidence of some samples enriched by barium. Although As, Cd and Ba concentrations were higher than TEL, they most likely corresponded to background levels. The obtained results indicated that activities of the PCM-9 and PGA-1 platforms may not be affecting the quality of nearby sediment. [Copyright &y& Elsevier]

Trace metals play an important role in marine biogeochemistry. However, the detailed distribution of trace metals in the Seas of Japan and Okhotsk remain unknown. Herein, we report the full-depth and section distributions of the dissolved (d), total dissolvable (td), and labile particulate (lp) phases of Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb in seawater samples collected from the Seas of Japan and Okhotsk during the GEOTRACES-Japan program. High lpM/tdM ratios suggest active scavenging in the Seas of Japan and Okhotsk. The lpAl and lpFe species were dominant in tdAl and tdFe, showing a strong positive correlation to each other in the both the Seas of Japan and Okhotsk. The maximum lpAl, lpFe, lpMn, and lpCo concentrations were observed at σ 0 = 26.8–27.0 for dense shelf water (DSW) in the Sea of Okhotsk, implying that a metal source is laterally transported to the western subarctic North Pacific. The high enrichment factors of dMn, dCo, dNi, dCu, dZn, dCd, and dPb in the surface water of the Sea of Japan were attributed to anthropogenic emissions of these metals. In addition, temporal variations of the trace metals were examined in the Sea of Japan. The distribution of dCd did not change significantly during 1984–2010; however, data suggest that lpMn and lpFe exhibited dynamic temporal and spatial variations. • Trace element distribution and stoichiometry in the Seas of Japan and Okhotsk studied. • Al and Fe are dominated by labile particulate species with a strong correlation. • Shelf water of the Sea of Okhotsk is a source of Mn, Fe, and Co to the Pacific Ocean. • Anthropogenic metals are enriched in surface water of the Sea of Japan. • Dissolved Cd profiles are consistent between 1984 and 2010 in the Sea of Japan. [ABSTRACT FROM AUTHOR]

In monomictic lakes, hypolimnetic anoxia is becoming severe in extent and duration over the past few decades. Understanding historical trends in hypolimnetic dissolved oxygen (DO) levels and the factors controlling them is crucial for effective protection and management of monomictic lakes everywhere, but the issue remains little studied in China. Here, our study elucidated the variation of hypolimnion DO and organic matter (OM) input in Lake Erhai (a typical monomictic lake in South-Western China) during the past 200 years, by using the geochemical profiles of elements (C, N, P, S, Mo, Ca, and Al) and aliphatic hydrocarbons in a dated sediment core. The values of element proxies (S concentrations, S/Al ratios, Mo enrichment factor, and total organic carbon/total P ratios) and pristane/phytane (Pr/Ph) ratios reflect relatively limited development of anoxia in the lake hypolimnion before 1990. Meanwhile, the n -alkane proxies (short-chain, middle-chain, and long-chain n -alkane abundances, n -C 17 / n -C 16 alkane ratios, and Paq) indicate relatively scant inputs of OM from phytoplankton and relatively high inputs of OM from terrestrial plants or from submerged macrophytes. Taken together the results show that OM supplied in this period did not deteriorate hypolimnion DO in Lake Erhai. The element proxies and Pr/Ph ratios point to that the lake had experienced a pronounced intensification of hypolimnetic anoxia after 1990, and the n -alkane proxies indicate that the lake was susceptible to severe eutrophication and phytoplankton blooms in this period. The synchronous sharp variation implies the decay of massive phytoplankton OM had severely consumed oxygen in the lake hypolimnion. The large surface area/depth ratio in Lake Erhai is conducive for an overturn of the water column during wind disturbance, which allowed the water column stratification and relating effects (e.g., hypolimnetic anoxia) less vulnerable to some aspects of climate change. [Display omitted] • We elucidated the dynamics of hypolimnion DO and OM input in Lake Erhai. • Increased hypolimnetic anoxia in Lake Erhai was driven by massive input of phytoplankton OM. • Dominant input from terrestrial plants correspond to weak hypolimnetic anoxia. • Increased input of submerged macrophytes cannot deteriorate hypolimnion DO. • The high surface area/depth ratio in Lake Erhai counteracts the climate warming effects. [ABSTRACT FROM AUTHOR]

Abstract: Marine pathogens of the genus Labyrinthula have been identified as the cause of wasting disease in seagrass systems in both temperate and subtropical regions. An understanding of the association between environmental factors and the prevalence of wasting disease in seagrass meadows is important for elucidating plant–pathogen interactions in coastal environments. We conducted a survey of 7 turtle grass-dominated beds within the Florida Keys National Marine Sanctuary to assess the relationship between environmental and biological parameters on seagrass health. All sites contained Labyrinthula spp.; the most pathogenic strain was obtained from an anthropogenically impacted site. Leaf and total biomass, in addition to root/rhizome carbon content, canopy light and % light transmitted, all displayed strong negative correlations with a wasting index (WI). It was noted that many of the same environmental measurements that showed negative correlations with WI also displayed strong positive correlations with canopy light levels. These data suggest that light availability may be an important factor that has previously been understated in the seagrass disease literature yet warrants more attention with respect to turtle grass susceptibility to infection. Studies such as this are important because they identify gaps in our understanding of plant–pathogen interactions in subtropical marine ecosystems. Furthermore, the relationships identified in this study may offer insight into which factors are most useful in identifying “at-risk” meadows prior to the onset of larger scale die-off events. [Copyright &y& Elsevier]

Abstract: The river Glerá in Northern-Iceland presents a convenient model for the evaluation of anthropogenic effects on sub-Arctic river microbiota. The river originates in a pristine valley, flows past a landfill site where leachate merges into the river, and subsequently through a small urban area. Our aim was to characterize the river microbiota in both its pristine and anthropogenically impacted state, particularly focusing on prospective surfactant degraders whose activity in the river water might contribute to the river's self-purification capacity. We sampled river water and riverbed sediment at 10 sampling sites that spanned the river from its pristine source to the estuary for culturable bacteria and extractable DNA. A few other biotopes in the catchment area were also sampled. A confirmed pure and viable culture collection of 170 isolates was generated and partially analyzed for identification by 16S rRNA gene sequencing, and for biodegradation of selected surfactants as well as glycans, protein and triglyceride. Protein-degrading pseudomonads are strongly represented in the culture collection, many of whom can also degrade selected surfactants. The collection also contains other members of the Gammaproteobacteria as well as the Alphaproteobacteria, Betaproteobacteria, Bacilli, Actinobacteria, Flavobacteria, and Sphingobacteria. Several isolates of all classes, except the Betaproteobacteria, displayed biodegradative activity. [Copyright &y& Elsevier]

Summary: This article evaluates the spatial and temporal changes in streamflow flashiness in 122 mountain catchments in Slovakia and Austria. The flashiness is quantified by the Richards–Baker flashiness index (FI), which is the ratio of absolute day-to-day fluctuations of streamflow relative to total flow in a year. The analysis is based on daily streamflow data from the period 1976 to 2005. The results show that the average day-to-day fluctuations of streamflow vary from 6% to 43%, depending on the catchment. The spatial pattern of the FI reflects the variations in the main geological units and generally shows a trend of decreasing flashiness with increasing size of the catchment. Statistically significant temporal trends in flashiness are found in 7 Slovak and 22 Austrian catchments. Most of these trends are related to anthropogenic effects, while, in a few catchments, the change in annual flashiness appears to be caused by changes in precipitation seasonality. A multivariate statistical analysis of FI indicates negative correlations with catchment area, mean catchment elevation, percents of forest cover, agricultural land and Quaternary geology. Positive correlations are found between FI and Tertiary and Calcareous geologies. Extrapolating the regression models beyond the observed range of catchment attributes used in the estimation leads to significant prediction errors. In order to better interpret the FI values, a statistically significant relationship was found between the FI and the frequency of peak flows exceeding the long-term mean as well as between the FI and the 5% quantile of daily streamflow. [Copyright &y& Elsevier]

Abstract: Multi-year (~7years) observations of aerosol optical and microphysical properties were conducted at a tropical urban location in Bangalore, India. As a consequence of rapid urbanization, Bangalore presents high local atmospheric emissions, which makes it an interesting site to study the effect of anthropogenic activities on aerosol properties. It has been found that both column (aerosol optical depth, AOD) and ground-level measurements (black carbon (BC) and composite aerosol mass) exhibit a weekly cycle with low aerosol concentrations on weekends. In comparison to the weekdays, the weekend reductions of aerosol optical depth, black carbon and composite aerosol mass concentrations were ~15%, 25% and 24%, respectively. The magnitude of weekend reduction of black carbon is as much as ~1μgm−3. The similarity in the weekly cycle between the column and surface measurements suggests that the aerosol column loading at this location is governed by local anthropogenic emissions. The strongest weekly cycle in composite aerosol mass concentration was observed in the super micron mass range (>1μm). The weekly cycle of composite aerosol mass in the sub micron mass range (<1μm) was weak in comparison to the super micron aerosol mass. [Copyright &y& Elsevier]

Abstract: Across North and South America, the final millennia of the Pleistocene saw dramatic changes in climate, vegetation, fauna, fire regime, and other local and regional paleo-environmental characteristics. Rapid climate shifts following the Last Glacial Maximum (LGM) exerted a first-order influence, but abrupt post-glacial shifts in vegetation composition, vegetation structure, and fire regime also coincided with human arrival and transformative faunal extinctions in the Americas. We propose a model of post-glacial vegetation change in response to climatic drivers, punctuated by local fire regime shifts in response to megaherbivore-driven fuel changes and anthropogenic ignitions. The abrupt appearance of humans, disappearance of megaherbivores, and resulting changes in New World fire systems were transformative events that should not be dismissed in favor of climate-only interpretations of post-glacial paleo-environmental shifts in the Americas. Fire is a mechanism by which small human populations can have broad impacts, and growing evidence suggests that early anthropogenic influences on regional, even global, paleo-environments should be tested alongside other potential causal mechanisms. [Copyright &y& Elsevier]

Abstract: As part of Integrated Campaign for Aerosols, gases and Radiation Budget (ICARB), cruise-based measurements of near-surface CO were carried out over Bay of Bengal (BoB) covering the latitude–longitude sector 3.5°N–21.0°N and 76.0°E–98.0°E, during winter months of December 2008 to January 2009. These in-situ measured CO mixing ratio varied in the range of 80–480ppbv over this marine environment with the distinct spatial pattern. The highest mixing ratios were measured over southeast-BoB with mean value of 379±58ppbv. CO mixing ratios were high over north-BoB compared to southern BoB. These in-situ measurements were compared with the satellite-measured surface CO obtained from Measurements of Pollution in the Troposphere (MOPITT) onboard TERRA and found to be in good agreement over most of the regions, except at southeast-BoB. Surface CO and column CO from MOPITT data showed a similar spatial pattern. Based on the analysis of airmass back-trajectories, satellite-based spatial map of CO distribution over Asian region and Potential Source Contribution Function analysis, different pathways of transport of CO were identified. Transport from northern landmass as well as from south-east Asia has a significant influence in the spatial variation of CO over BoB. Winter-time mixing ratio of CO was found to be higher compared to those measured during other campaigns conducted during February–March 1999, 2001 (pre-monsoon) and September–October, 2002 (post-monsoon). [ABSTRACT FROM AUTHOR]

Abstract: There is substantial interest in how mortality rates affect animal populations, but mechanisms explaining when and under what circumstances particular causes of death incur demographic responses are far from clear. In theory, small or expanding populations should experience additive mortality from anthropogenic causes of death, but whether such effects are homogenous across a population or expressed only in certain high-risk individuals is open for debate. We used competing risks models to analyze mortality patterns among radio-collared wolves (Canis lupus, n =711) from three populations in northwestern United States (1982–2004), and evaluated the degree to which anthropogenic mortality was additive vs. compensatory to natural demographic processes. Almost 80% (n =320) of wolves dying of known fates were killed by anthropogenic causes (legal control, illegal killing, harvest in Canada, vehicle collision), and additive effects of anthropogenic mortality were most pronounced in northwestern Montana where wolf exposure to humans and livestock was high compared to either the Greater Yellowstone Area or central Idaho, where anthropogenic risk was lower. In contrast, risk from natural hazards was lower in northwestern Montana than in the other areas, implying some degree of compensatory mortality from anthropogenic risk. Animals recruited to the study following human–wolf conflict had markedly higher anthropogenic risk than those recruited for standard monitoring purposes, and juvenile wolves as well as dispersers, succumbed to higher anthropogenic risk. Multivariate models revealed that increasing wolf population density promoted higher anthropogenic risk and reduced natural risk, indicating that partially-compensatory effects of anthropogenic mortality actually became increasingly additive with population density. The observed compensatory mortality and hazard heterogeneity in our study implies that demographic responses to mortality risk may be complex and more subtle than previously thought; the density-dependent effect of anthropogenic mortality portends a stabilizing influence of humans on recovering wolf populations. We conclude that future assessment of the role of anthropogenic mortality should include individual-based hazard estimation as a complement to traditional population-level approaches. [Copyright &y& Elsevier]

Abstract: This paper focuses on identifying changes in the tidal range and the duration of the flood tide in the Pearl River Delta region, China. Mann–Kendall test and regression methods are employed to verify the existence of trends in the annual tidal range and duration series (from the 1950s to 2005) at 17 stations in the 3 major tributaries of the delta. The research results indicate that generally there is an increasing trend in the tidal range and flood tide duration at most of the stations in the channel network. Moreover, the more upstream the location of the station, the more obvious the change in trend is, and these increasing trends are all significant at the stations in the upper part of the delta. Specifically, the tidal range at Shilong station in the East River has increased abruptly since the middle of the 1980s such that the mean level of post-1990 data is approximately three times that for pre-1985. Most stations near the mouth of the estuary show significant downward trends in the tidal range and flood tide duration. Results of the intersection point of the Mann–Kendall test curves for these Pearl River Delta stations appear mostly in 1980s–1990s, indicating that a noticeable change point occurs during this period. Human activities in the Pearl River Delta reached their peak during the 1980s. Among these, large-scale and long-term sand excavation modified the hydrodynamic regime dramatically in a way that increased the water depth and lowered the level of the riverbed, leading to an increased tidal prism and upstream movement of the tidal limit. Land reclamation is also likely to have had a relatively large effect on the tidal range and flood tide duration at stations near to the estuary mouth. Changes in other factors, such as freshwater flow and sea-level rise, seem to be of relatively minor importance. It is noteworthy that in a dry season the tidal dynamics are greatly enhanced and has resulted in strong saltwater intrusion into the estuary in recent years. [Copyright &y& Elsevier]

Abstract: Sedimentation along the central Adriatic coastline of Italy results from a series of small, distributed fluvial sources (i.e., a line source), draining the Apennine Mountains. These rivers deliver ∼3×107 t y−1 of sediment, contributing to the formation of a shore-parallel shelf clinoform that has developed throughout the Holocene. Across-shelf sediment accumulation rates, calculated from 210Pb (half-life 22.3 years) measurements, are greatest on the clinoform foreset (∼1 cm y−1), which is characterized by seafloor crenulations in a few areas. However, for some cross-sections of the clinoform, accumulation rates are not significantly higher on the foreset than on the topset and bottomset, indicating that the clinoform may not be actively prograding in those areas today. Accumulation rates increase southward along the shelf and are greatest near the Gargano Peninsula (∼1.7 cm y−1). Between Ravenna and the Gargano Peninsula, 3.1×107 t y−1 of sediment accumulate on the Apennine shelf. Although the amounts of sediment supply and accumulation are about the same, additional Po River sediment is thought to enter the system from the north and some sediment is transported beyond the Gargano Peninsula to the south. Anthropogenic activities, particularly dam construction following World War II, have significantly impacted sedimentation in this region. Changes in 210Pb profiles document reduction in sediment accumulation. However, observations during winter 2002–2003 using the short-lived radioisotope 7Be (half-life 53.3 d) have indicated that some new sediment is delivered to the shelf during periods of elevated discharge, so dam entrapment is not complete. [Copyright &y& Elsevier]

Summary: Empirical relationships coupled with the field measurements were used to assess water discharge and sediment load from an anthropogenically-altered drainage basin into Sepetiba Bay in southeastern Brazil. Discharge into Sepetiba Bay is modified by large-scale water diversion from the Paraíba do Sul River, which is one of the more important and impacted rivers in Brazil. The discharge into Sepetiba Bay has increased threefold, from 41 to 129m3/s on average, since the water redistribution began. Sediment budget calculations indicate retention of a large fraction of the sediment load by five reservoirs within the drainage system but with highly variable infilling rates. As a consequence the water diversion scheme has lead to a 28% increase in sediment delivery to Sepetiba Bay or 270×103 t/yr. The Paraíba do Sul River contributes most of the freshwater input into Sepetiba Bay, whereas the sediment load to the bay is mainly contributed by the local drainage basins. [Copyright &y& Elsevier]

Abstract: Results of various authors on long-term trends in foF2, which is equivalent to the maximum electron density in the ionosphere, and their interpretation do not reveal a consistent pattern. Therefore, a joint analysis of one carefully selected dataset was performed by six teams, which used different approaches to trend determination. High-quality data of station Juliusruh (54.6°N, 13.4°E) for noon (average from 10 to 14UT) were used for the period of two solar cycles from minimum to minimum (1976–1996). Juliusruh is relatively sensitive to geomagnetic activity as an almost subauroral station, which might play some role in interpretation of trend results. Various methods provide results, which differ to some extent, even when one co-author applies different methods. Another source of differences is application of various ways of removal (or at least large suppression) of the effect of solar (and geomagnetic) activity. Nevertheless finally most teams obtained quite comparable results. Interpretation of the observed trends is not unique—co-authors consider either the long-term change in geomagnetic activity, or anthropogenic effects to be predominantly responsible for trends. There is some generally accepted output from the joint analysis. All trends are either negative or insignificant. Data corrections with sunspot number (R), F10.7 adjusted to the Sun–Earth distance, observed F10.7, adjusted E10.7 and observed E10.7 result in somewhat different trends; the observed F10.7 and E10.7 appear to be the best correcting factor. The trends in foF2 are very small, of the order of −0.01MHz/year, much smaller than the solar cycle effect and, therefore, sensitive to the solar activity correction. The Juliusruh dip angle increased very little over the period 1976–1996 and the possible impact of that increase on trends is negligibly small. [Copyright &y& Elsevier]

Abstract: This study investigates how subsurface flowpaths are altered by forest roads and how these changes influence shallow landsliding susceptibility in steep, forested landscape. A simple conceptual model of the effect of forest roads on hillslope subsurface flow is developed. The model is incorporated into a hydro-geomechanical, threshold-based model for slope instability. In the model, the occurrence of shallow landsliding is evaluated in terms of drainage areas, ground slope and soil properties (i.e., hydraulic conductivity, bulk density, and friction angle). Model results allow to quantify the influence of roads on shallow landsliding hazard across a landscape and to generate hypotheses about the broader geomorphic effect of roads. Modelling results are compared with field data collected in four sites located in north-eastern Italy. Observed landslide patterns are broadly consistent with model estimates, a finding that underscores the utility of this simple approach for predicting the geomorphic effects of forest roads constructed on steep slopes. The approach used in this study may be useful for defining criteria for road design that reduce the effects of roads on geomorphic processes. [Copyright &y& Elsevier]

The Guadalquivir River is the major water source of the south of Spain. In this work, we have selected an area, about 115 km long, from Alcalá del Río to the mouth of the river, to study the effects caused by human activities on water quality. The area under study includes several sensible points as the town of Seville, the Guadiamar River (where an important mine spill took place on April 1998) and the Doñana National Park.We measured several physico-chemical variables in the 26 sampling stations located along the river, and in three different campaigns from 2001 to 2002. With the results we built the data matrix, which was analysed by factor analysis/principal components analysis (FA/PCA) and cluster analysis (CA). This analysis allowed the identification of four different zones in the river, with different water quality. The first zone (zone 1A) comprised from Alcalá del Río to Seville. The second zone (zone 1B) was the city of Seville, and as a consequence, presented higher concentrations of several variables such as nitrite, ammonium or manganese. The third zone (zone 2) included from Seville to the Guadiamar River. In this area, agriculture is the main activity, and then, higher concentrations of suspended solids and phosphate were measured. In terms of water quality, this zone was partially similar to zone 1A, and partially similar to the fourth zone, starting in the Guadiamar River and finishing in the mouth of the Guadalquivir River. The water in this last zone (zone 3) is mainly estuarine water. Thus, its quality is influenced by seawater input, and also by the inputs from the Guadiamar River (coming from a mining area), and presented higher copper concentration.Three principal components were extracted, explaining the 79.1% of the data variance. PC1 (46.9% variance) was mainly associated with nitrite, ammonium and manganese. PC2 (22.5% variance) was mainly associated with suspended solids and phosphates. PC3 (9.7% variance) was mainly correlated to nitrate and copper concentration. [Copyright &y& Elsevier]

We have studied growth and estimated recruitment of massive coral colonies at three sites, Kaledupa, Hoga and Sampela, separated by about 1.5 km in the Wakatobi Marine National Park, S.E. Sulawesi, Indonesia. There was significantly higher species richness (P<0.05), coral cover (P<0.05) and rugosity (P<0.01) at Kaledupa than at Sampela. A model for coral reef growth has been developed based on a rational polynomial function:dx/dt=a1W+a2W2+a3W3+…anWn/1+b1W+b2W2+b3W3+…bmWmwhere dx/dt is an index of coral growth with time; W is the variable (for example, coral weight, coral length or coral area), up to the power of n in the numerator and m in the denominator; a1……an and b1…bm are constants. The values for n and m represent the degree of the polynomial, and can relate to the morphology of the coral. The model was used to simulate typical coral growth curves, and tested using published data obtained by weighing coral colonies underwater in reefs on the south-west coast of Curac¸ao [‘Neth. J. Sea Res. 10 (1976) 285’]. The model proved an accurate fit to the data, and parameters were obtained for a number of coral species. Surface area data was obtained on over 1200 massive corals at three different sites in the Wakatobi Marine National Park, S.E. Sulawesi, Indonesia. The year of an individual's recruitment was calculated from knowledge of the growth rate modified by application of the rational polynomial model. The estimated pattern of recruitment was variable, with little numbers of massive corals settling and growing before 1950 at the heavily used site, Sampela, relative to the reef site with little or no human use, Kaledupa, and the intermediate site, Hoga. There was a significantly greater sedimentation rate at Sampela than at either Kaledupa (P<0.0001) or Hoga (P<0.0005). The relative mean abundance of fish families present at the reef crests at the three sites, determined using digital video photography, did not correlate with sedimentation rates, underwater visibility or lack of large non-branching coral colonies. Radial growth rates of three genera of non-branching corals were significantly lower at Sampela than at Kaledupa or at Hoga, and there was a high correlation (r=0.89) between radial growth rates and underwater visibility. Porites spp. was the most abundant coral over all the sites and at all depths followed by Favites (P<0.04) and Favia spp. (P<0.03). Colony ages of Porites corals were significantly lower at the 5 m reef flat on the Sampela reef than at the same depth on both other reefs (P<0.005). At Sampela, only 2.8% of corals on the 5 m reef crest are of a size to have survived from before 1950. The Scleractinian coral community of Sampela is severely impacted by depositing sediments which can lead to the suffocation of corals, whilst also decreasing light penetration resulting in decreased growth and calcification rates. The net loss of material from Sampela, if not checked, could result in the loss of this protective barrier which would be to the detriment of the sublittoral sand flats and hence the Sampela village. [Copyright &y& Elsevier]

We investigated the effects of hydroelectric development on the movements and space-use of caribou (Rangifer tarandus caribou) in west-central Newfoundland, Canada. We compared patterns of range use, site fidelity, and timing of migration before, during, and after project construction. Coincidental with the first year of project construction, caribou were less likely to be found within 3 km of the site; this persisted at least 2 years after construction was completed. Relative timing of migration was individual-specific; the rank order of spring arrival on, and autumn departure from, the calving and summer grounds tended to be consistent year-to-year. This is the first report of such individual-specific consistency in migration for a non-avian species. This predictability disappeared during development: the year-to-year consistency of fall and spring migration among individuals was apparent before and after construction, but not during construction. Variation in calving site fidelity was correlated to year-to-year differences in snowfall. We conclude that the development caused a disruption of migrational timing during construction and longer-term diminished use of the range surrounding the project site. Long-term studies of individually marked animals can aid in environmental assessments for migratory animals. [Copyright &y& Elsevier]

The modern hydrological regime of the Dead Sea is strongly affected by anthropogenic activity. The natural fresh water budget has changed mainly due to the drastic reduction of runoff. Since 1977, the surface level of the Dead Sea has been lowered by an average rate of about 60 cm/year and for the period from 1998 to 2000, the lowering rate has reached about 100 cm/year. As a result of the runoff reduction, the upper layer salinity of the Dead Sea has increased and the gravitational stability of the water body was diminished. Eventually, during the winter of 1978–1979, the lake waters overturned, bringing to an end the long-term stable meromictic11Meromictic lake—a lake that undergoes incomplete mixing of its waters during periods of circulation. Holomictic lake—a lake that undergoes a complete mixing of its waters during periods of circulation or overturn. hydrological regime. The lake entered a new phase in which its hydrological regime switches between holomictic and meromictic regimes, depending on the size of the runoff into the lake (i.e. the amount of precipitation in the lake''s watershed). The first holomictic period, 1979–1980, lasted for 2 months only. It was succeeded by a 4-year meromictic period (1980–1983). The second holomictic period lasted for 9 years (1983–1991). The rainy winter of 1991–1992 resulted in an almost 2-m sea level rise. The upper layer with a relatively low salinity was restored and a new meromictic period persisted for 4 years, until winter 1995–1996. During the last meromictic period, the hydrological regime of the Dead Sea was characterized by following long-term trends: the depth of the summer thermocline increased from 12–15 to 25–30 m; the quasi-salinity of the upper layer, initially of about 164 kg/m3, increased rapidly at a rate of about 16–18 kg/m3/year; the quasi-salinity of the deep water, initially of about 235 kg/m3, decreased slowly at a rate of about 0.08–0.10 kg/m3/year (for the sake of comparison, a quasi salinity of 235 kg/m3 is the equivalent of 280‰ “usual” salinity); and the winter minimal temperature of the upper layer, initially of about 16 °C, increased rapidly at a rate of about 2 °C/year. In November 1995, the latest meromictic period of the Dead Sea came to an end. During the present holomictic period, 1996–2000, the hydrological regime of the Dead Sea is also characterized by long-term trends: the quasi-salinity of the entire Dead Sea increased at a rate of about 0.5 kg/m3/year, with practically no decrease during the winters; the temperature of the deep water mass increased with a rate of about 0.25 °C/year; and the period of vertical convection of the entire water column, initially about 3 months, increased at a rate of about 1 week/year. Moreover, we observed that the temperature and salinity of the bottom layer in the deepest part of the Dead Sea raised by about 0.5–0.6 °C and 0.15–0.25 kg/m3 during each holomictic summer. [Copyright &y& Elsevier]

In this study, distributed lag nonlinear models (DLNM) were built to characterize the non-linear exposure-lag-response relationship between the concentration of PM 2.5 and O 3 and multiple influencing factors, including basic meteorological elements and precursors. Then, a stratified analysis of different years, seasons, pollution levels, and wind direction was conducted. DLNMs and coupled Weather Research and Forecasting Model-Community Multi-scale Air Quality Model (WRF-CMAQ) were used to evaluate PM 2.5 and O 3 changes attributed to meteorological conditions and anthropogenic emissions comparing 2020 with 2016. As DLNMs showed, PM 2.5 pollution was promoted by low wind speed, high temperature, low humidity, and high concentrations of SO 2 , NO 2 , and O 3 , among which NO 2 tended to be the dominant influencing factor. O 3 pollution was promoted by low wind speed, high temperature, low humidity, high concentration of PM 2.5 and low concentration of NO 2 , among which temperature tended to be the dominant influencing factor. Moreover, north-south and easterly winds showed the greatest contribution to PM 2.5 and O 3 , respectively. Both DLNMs and CMAQ showed that anthropogenic factors alleviated PM 2.5 pollution but aggravated O 3 pollution in 2020 in comparison with 2016, so did meteorological factors, but with smaller impacts. And anthropogenic influences were more evident in heavily polluted seasons for both PM 2.5 and O 3. This research may help understand the influencing factors of PM 2.5 and O 3 and provide scientific guide for abatement policies. Moreover, the good consistency in the results obtained from DLNMs and CMAQ indicated the reliability of the two models. [Display omitted] • Meteorology and precursors have nonlinear and lagged effects on PM 2.5 and O 3. • NO 2 and temperature are the dominant factors influencing PM 2.5 and O 3 respectively. • Meteorological and anthropological change both alleviated PM 2.5 but aggravated O 3. • Anthropologically-driven change were more evident in heavy polluted seasons. Based on results obtained from DLNMs and CMAQ, meteorological change and anthropogenic change both alleviated PM 2.5 pollution but aggravated O 3 pollution in 2020 in comparison with 2016. [ABSTRACT FROM AUTHOR]

• In Bologna (Northern Italy) water withdrawals were significantly reduced in 2010. • Piezometric, CGNSS and rainfall time series have been compared. • Several piezometers undergo a clear increase in the water level after 2010. • Thanks to PCA we spotted the effect of withdrawals reduction in the CGNSS data. • Rainfall-related hydrological response strongly depends on the geological setting. Like other sedimentary plains, the Po Plain in Northern Italy has largely subsided due to natural processes and human activities. Displacements of the Earth surface of hydrological origin are caused by groundwater changes, which in turn, are expected to be related to rainfall changes. In the Bologna metropolitan area (located in the Southeastern border of Po Plain), the 2010 politic decision of dismissing civil water supply from the groundwater withdrawal has provided us the opportunity to test a methodology for the retrieval of an anthropic effect in two different data sets: vertical displacements measured by continuous GNSS sites and piezometric water table fluctuations. The data sets have been analyzed by means of the Principal Component Analysis (PCA) and compared to rainfall time series from the Po Plain rain gauges. Several piezometers undergo a clear increase in the water level following the withdrawal decrease. Differently, the anthropic induced surface displacements are significantly smaller than the ones induced by rainfall. Accordingly, without a multivariate analysis such an effect on vertical displacements would have remained hidden in the raw time series. Only looking at the spatial distribution of the principal components we have highlighted that anthropic effects are local and present even in GNSS data, entailing for the 2010 case a decrease of about 4 mm/y of vertical velocity in some sites closest the withdrawal wells. Moreover, the multivariate analysis allowed us to assess that, on time scales larger than months, the rainfall-related hydrological response of vertical displacement depends on the geological setting. In the Apennines chain a water level increase causes subsidence, in agreement with the predictions of elastic models, whereas in the Po Plain it causes uplift, suggesting a dominant poro-elastic response, in agreement with the guess that the subsidence of the Po Plain is related to soil compaction. Our results suggest that in cases of the aquifers over-exploitation, a PCA analyses and the combined use of different observables such as GNSS, piezometers time series, rainfall data, geological setting allow getting a correct identification of the anthropic and natural signals. [ABSTRACT FROM AUTHOR]

• Cyclotella meneghiniana predominates over Cyclotella gamma along the river. • Variation of river's algal diversity accords with intermediate disturbance hypothesis. • DO and organics positively affect algae in source and anthropic area, respectively. • Human disturbance more clearly affects abundant taxa rather than rare taxa. Phytoplankton, as an important primary producer in rivers, greatly affects an aquatic ecosystem's function and biodiversity. However, the effect of human activities on phytoplankton community composition remains largely unstudied in rivers. Herein a typical temperate river, Xiaoqing River in the north of China, was the target to investigate the phytoplankton distribution and regime along stretches subject to different human disturbances. Other than in the wetland located in a tributary of the river, which had Cyanophyta as the dominant phylum, Bacillariophyta overwhelmingly predominated across the sampling sites. Notably, the main genus was Fragilaria in the source region of the river, while Cyclotella dominated along the trunk of the river, and the main species shifted from Cyclotella gamma Sovereign to Cyclotella meneghiniana Kützing when the river entered the sea. Phytoplankton community structures in the source region were affected to some extent by DO and pH, and in the human activity areas were mainly influenced by nitrogen, phosphorus, and COD Mn. Human interference led to a decrease in diatom density by increasing the concentration of nutrients and organic matter. Furthermore, algal diversity was higher and density was lower in the disturbed areas than in the catchment areas, in accordance with the intermediate disturbance hypothesis. It was also found that human activities more obviously affected the abundant than rare phytoplankton communities. [ABSTRACT FROM AUTHOR]

Nitrogen mineralization is a critical biogeochemical process that transfers organic nitrogen into inorganic forms using heterotrophic microorganisms. However, few studies have focused on this potential nutrient supplier. In this study, the composition of sediment organic nitrogen (SON) was studied, and nitrogen mineralization flux entering the water column was quantified. The results indicate that acid-hydrolyzable nitrogen (AHN) accounts for more than 40% of the SON, especially in the riverine input and marine aquaculture areas, which had significantly higher concentrations than the bay mouth area. Similar results were found for the ammonium nitrogen (AN), amino-sugar nitrogen (ASN), the total hydrolyzable amino acid (THAA), and unidentified hydrolyzable nitrogen (HUN). The mineralization rate in the marine aquaculture area was as high as 9.03 ± 1.33 mg·kg−1·d−1, while those of the riverine input (4.77 ± 1.55 mg·kg−1·d−1) and bay mouth (5.12 ± 1.42 mg·kg−1·d−1) areas were lower. The SON fractions, including the AHN, AN, ASN, and AAN, could obviously affect the mineralization of the SON. However, the extracellular enzymes, including proteinase and urease, are the predominant factors controlling the SON mineralization process. Anthropogenic activities, including riverine input and marine aquaculture, exert significant influences on the fractions and mineralization of the SON, and thus, they may increase the amount of dissolved inorganic nitrogen in the bottom of the water column in Daya Bay. • SON fractions was higher in the aquaculture area. • The mineralization potential was higher in the aquaculture area than the other two areas and bay mouth. • The extracellular enzymes are the predominant factors controlling the SON mineralization process. [ABSTRACT FROM AUTHOR]

• Human activities may have a hidden impact on animal populations. • We analyzed the butterflies' physiology according to forest cover and tourists. • Markers of immune response and oxidative stress increased as forest cover decreased. • Survival decreased as forest cover decreased and tourist number increased. • It is important to establish a regular monitory program of the monarchs' physiology. The deleterious anthropogenic impact on animals is often hidden and not revealed in indexes of mortality in populations. Hence, animal monitoring should not only involve population numbers and survival, but also the individual physiological condition. Here we analyzed the physiological condition of the monarch butterfly Danaus plexippus in terms of protein content, immune response (proPhenoloxidase [proPO], phenoloxidase [PO] and lytic activity [LA]) and antioxidant defense (total antioxidant capacity [TAC] and superoxide dismutase [SOD]). We also evaluated survival rates after injecting Staphylococcus aureus. These parameters were compared between 5 different winter aggregations in Mexico (Chincua, Rosario, Malacatepec, Xoconusco and Albarranes). Chincua had the lowest forest cover (43.7%) and it is open for tourism, while Albarranes had the highest forest cover (78%) and had no tourist activities. We found no differences in the wing size, PO nor LA between sites. Albarranes showed the highest protein content. The proPO and TAC measurements were highest at Chincua. In addition, Chincua showed the lowest survival when injected with the bacteria. This suggests that the higher values of immune response and oxidative defense are not indicators of butterfly condition at the overwintering sites. However, forest cover seems to be more important for their survival and physiological condition. We highlight the importance to establish a regular monitoring program of the butterflies condition to detect potential hidden cost on its physiology, which may impact not only their survival during the overwintering season, but also during their north migration to their reproductive sites. [ABSTRACT FROM AUTHOR]

Anchor pipe vibration embedment operations during the construction of seed mussel collectors were performed in the Wadden Sea, a designated World Heritage Site by UNESCO in 2009. We recorded 200 min of underwater noise during the construction of seven anchor pipes. Underwater noise was recorded simultaneously at three positions with a water depth of 9 m with increasing distance to the construction site to assess the disturbance potential to the marine fauna. The recorded vibration embedment noise was a continuous sound with durations of 2–55 s, with most energy below 1 kHz and peak frequencies around 900 Hz. Background noise level at a distance of approximately 1 km increased around 13 dB at frequencies between 800 and 1000 Hz. We estimated the sound propagation by a non-linear logarithmic regression by means of the intercept, slope and attenuation factor, which allowed us to evaluate the received sound levels that reach an animal in certain distances from the construction site. The estimated sound exposure level (SEL) of the source was 148.2 dB re 1 μPa2s and the median SEL ranged from 120 to 99 dB re 1 μPa2s at distances between 394 and 2288 m, respectively. Behavioural thresholds for indigenous species of marine mammals in the Wadden Sea as well as representative fish species were used to determine effect radii of vibration embedment noise. Our study showed that the detected anchor pipe vibration embedment noise might exert a behavioural reaction on a local scale. Marine mammals could be affected by the construction operations up to a distance of 375 m and fish up to a distance of 766 m. These zones of responsiveness for vibration embedment operations are relatively small, compared to pile driving, which is regularly used during construction operations. Our study shows that it is important to monitor and assess any kind of noise introduction to verify, whether a sustainable human use with respect to the complied guidelines is ensured without affecting the marine fauna. That is the first step to maintain a good environmental status as implemented in the MSFD. • Source level of the vibration embedment noise was 148.2 dB re 1 μPa2s. • Median sound exposure levels ranged from 120 to 99 dB re 1 μPa2s at distances between 394 and 2288 m. • Vibration embedment noise might exert a behavioural reaction on a local scale. • Marine mammals and fish may be affected to distances of 375 and 766 m, respectively. [ABSTRACT FROM AUTHOR]