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Animal-vehicle collisions (AVCs) cause animal death, human injury, and vehicle damage. Uncovering the general patterns and related ecological processes of AVCs is useful for developing mitigation strategies. We examined some previous patterns about AVCs from records in Alabama during 2001 to 2011. The results confirm that: (1) there was a seasonal pattern, with >50% of AVCs occurring in winter; (2) AVCs occurred most frequently at dawn and dusk in the diurnal pattern; and (3) most AVCs occurred on county highways. However, interstate and federal highways had higher numbers of AVCs per km of road. Counties within metropolitan areas had more AVCs. We analyzed 1,000 AVC cases selected at random from the all reported cases and found that 74% of AVCs had forested landscapes on both sides the road. At the county level, AVCs occurred more frequently in areas with greater human population density and less frequently in areas with few roads. The implications for mitigating human-wildlife conflict are provided based on a system view of vehicles, roads, and animals. [ABSTRACT FROM AUTHOR]

This paper makes an analysis on the international tourists of the 17 cities in Hubei Province from 2006 to 2011. The temporal dynamics of the inbound tourists of the cities is analyzed by using Inter-annual Concentration Index, the evolution of the spatial pattern of the inbound tourist scale of the cities in Hubei Province is analyzed by using the standard deviation, coefficient of variation, Gini coefficient, primacy ration, Herfindah Index and the rank-size rule And analyzes the influencing factors of the in-bound tourism development with spatial econometric model . The results indicate that: 1 ) the inter-annual variation of the international tourists remains stable in most cities in Hubei, with Qianjiang, Shennongjia and Suizhou as exceptions to fluctuate most over time; 2) the scale of international tourism in the cities appears to be the first-place dis-tribution, with the development of the primacy city faster than the small and medium-ranked cities and the medium-ranked cities developing fast and becoming more in num-bers, which makes the distribution of the inbound tourist scale become scattered and non-balanced; 3) tourism service facilities, location and traffic conditions, the develop-ment of tertiary industry development all have a significant role in promoting on inbound tourism development, but the economic development role in promoting inbound tourism has not effectively work out and also there is the "resource curse" phenomenon. [ABSTRACT FROM AUTHOR]

With ongoing economic and social development, natural habitats are becoming increasingly fragmented, blocking habitat connections and reducing landscape connectivity. The study of changes in ecological connectivity can provide valuable information for habitat and landscape restoration, which are necessary for sustainable regional development. Despite the growing interest in this issue, studies that reveal the change in ecological connectivity in the compounded areas of ecological vulnerability and deep poverty are still lacking. In this paper, one of the most underdeveloped and ecologically fragile southwestern ethnic regions of China, the Sanzhou region of Sichuan Province, was the study area. Based on a vector map of current land-use status and vector data on ecosystem factors and nature reserves in 2010 and 2015, the change in ecological connectivity was analyzed using the minimum cumulative resistance model using GIS spatial analysis method. Firstly, ecological sources were identified based on the distribution of ecological functional areas. Secondly, the ecological resistance surface based on ecosystem service value is revised by integrating the three dimensions of topography and hydrology, ecological environment and development, and utilization intensity. Finally, the ecological connectivity of ethnic areas in southwest China in 2010 and 2015 was compared and analyzed through the perspective of ecological resistance. The results show that: (1) From 2010 to 2015, the overall ecological connectivity decreased. (2) There were six areas of high ecological resistance featuring human activity and ecological degradation: the Anning River Valley in Liangshan Prefecture, Ganzi, Dege and Luho counties in Ganzi Prefecture, and Ruoergai and Hongyuan counties in Aba Prefecture. (3) Low ecological resistance areas were more numerous and widely distributed, forming an ecological protection barrier for the three autonomous prefectures, and regulating and protecting their natural environments. It is necessary to maintain and strengthen this protection; accordingly, measures are proposed to improve ecological connectivity. This study provides a reference for achieving ecological security and harmonious coexistence between humans and nature in this region.

At the beginning of the 21st century, ongoing climate change led to research into extreme streamflow phenomena. This study aimed to assess the patterns of low-flow changes in different hydrological regions of Lithuania using selected hydrological indices (the annual minimum 30-day flow (m3 s−1) of the warm period—30Q), its duration, and deficit volume (below the 80th and 95th percentile flow: 30Q80 and 30Q95). Differences in low-flow indices in separate hydrological regions and over different periods (1961–2020, 1961–1990, 1991–2020) were analyzed, applying the HydroOffice tool, the TREND software package, and mapping using the Kriging interpolation. The highest specific indices of 30Q were estimated in the Southeastern hydrological region (3.97 L/s·km2) and the lowest in the Central hydrological region (1.47 L/s·km2). In general, the 30Q values in the periods 1961–2020 and 1991–2020 had no trends. In 1961–1990, trends in 30Q data were significantly positive, and positive in most investigated rivers of the Western and Central hydrological regions. The average number of dry days at both thresholds decreased in the Western and Southeastern hydrological regions and increased in the Central hydrological region comparing two subperiods. [ABSTRACT FROM AUTHOR]

N -nitrosodimethylamine (NDMA) and N -nitrosomorpholine (NMOR) and their specific precursors (N , N -dimethylformamide [DMF] for NDMA and morpholine [MOR] for NMOR) were widely identified in runoff of urban area around the southern Lake Biwa basin, Japan. It was thought that this runoff might constitute a non-point source of the four compounds in rivers and sewage treatment plants (STPs) during heavy rainfall events. We investigated the spatiotemporal patterns of NDMA, NMOR, DMF and MOR in runoff and rivers in rainy days. NDMA and NMOR were detected in concentrations of up to 295 ng/L, while DMF and MOR were detected in concentrations of up to 33.7 µg/L. Continuous sequential sampling over periods of 24 or 48 h at the largest STP in the study area revealed that the four compounds in the primary effluent (PE) each had higher mass fluxes during heavy rainfall events than on dry days. This phenomenon might be contributed to non-point sources (e.g., runoff) from infiltration/inflow related to rainwater into sanitary sewers. Moreover, the four compounds were confirmed to have higher mass fluxes in the final effluent of the STP during periods of PE bypass (1.3–1.7 times for NDMA, NMOR, and MOR; over 200 times for DMF; on average) than that on dry days because of increasing inflow during heavy rain than during periods without PE bypass in dry weather. [Display omitted] • Runoff was identified as a non-point source of NDMA, NMOR, DMF, and MOR. • NDMA, NMOR, DMF, and MOR were investigated in urban rivers affected by heavy rain. • Heavy rain increased mass fluxes of these four compounds in STP primary effluent. • Sewage bypass increased mass fluxes of these four compounds in STP final effluent. [ABSTRACT FROM AUTHOR]

With climate warming and intensification of human activities, the eco-environmental problems of lakes in middle and high latitudes become increasingly prominent. Qinghai Lake, located in the northeastern of the Tibetan Plateau, is the largest inland saltwater lake in China. Recently, the problem of Cladophora blooms has been widely concerning. In this study, the area of floating Cladophora blooms (hereafter FCBs) in Qinghai Lake from 1986 to 2021 was extracted using Floating Algal Index (FAI) method based on Landsat TM/ETM+/OLI and Sentinel-2 MSI images, and then the intra- and inter-annual variation characteristics and spatial patterns of FCBs were analyzed. The results show that the general change trend of FCBs in Qinghai Lake featured starting in May, expanding rapidly from June to August, and increasing steadily from September to October. From 1986 to 2021, the area of FCBs in Qinghai Lake showed an overall increasing trend in all months, with the largest increase in July at 0.1 km2/a, followed by October at 0.096 km2/a. Spatially speaking, the FCBs area showed a significant increasing trend in the northern Buha River estuary (BRN) and southern Buha River estuary (BRS) regions, a slight increase in the Shaliu River estuary (SR) region, and a decreasing trend in the Quanji River estuary (QR) region and the Heima River estuary (HR) region. The correlation between the meteorological factors and the changes in FCBs was weak, but the increase in flooded pastures in the BRN region (Bird Island) due to rising water levels was definitely responsible for the large-scale increase in FCBs in this region. However, the QB, northeastern bay of Shaliu River estuary (SRB) and HR regions, which also have extensive inundated grassland, did not have the same increase in FCBs area, suggesting that the growth of Cladophora is caused by multiple factors. The complex relationships need to be verified by further research. The current control measures have a certain inhibitory effect on the Cladophora bloom in Qinghai Lake because the FCBs area was significantly smaller in 2017–2020 (5.22 km2, 3.32 km2, 4.55 km2 and 2.49 km2), when salvage work was performed, than in 2016 and 2021 (8.67 km2 and 9.14 km2), when no salvage work was performed. [ABSTRACT FROM AUTHOR]

Anthropogenic interferences to large river basins are triggering unprecedented changes to earth surface processes. The upper reach of the Yangtze River Basin (UYRB) is a typical example, where a large number of mega dams and reservoirs (storage capacity > 10 8 m3) have been, being, or will be constructed in clusters especially in the 21st Century. Limited studies have quantitatively demonstrated the impact of these reservoirs in trapping sediment; the spatial and temporal patterns of the responses of sediment flux and sedimentation have yet to be elucidated. We develop formulas to estimate basin-wide reservoir trapping efficiency typically for mega cascade reservoirs which better reflect the reality than traditional formulas. Results show that the sediment load at Yichang (downstream of the Three Gorges Reservoir or TGR) dropped below 1 × 10 8 t, smaller than the amount trapped in reservoirs upstream (1.6 × 10 8 t) for the first time in 2003, and it further decreased to 2% of the historical value since 2006. The overturn of sedimentation-flux relation also occurred at Pingshan (outlet of the Jinsha River Basin) at 2014, after the mega dams Xiluodu and Xiangjiaba were put into operation. The total annual sedimentation in UYRB increased from 3 × 10 8 t in 2001–2010 to 4.7 × 10 8 t in 2011–2015, meaning that 92% of the sediment was trapped; no considerable increase will be made in the future (after 2021) despite new reservoirs still being constructed. After 2016, the Jinsha River Basin became the most important trapper while the most unimportant contributor to the incoming sediment to the TGR where the annual sedimentation was apparently relieved (from 1.4 × 10 8 t before 2015 to 0.7 × 10 8 t after 2016). Serious channel erosion is expected to happen due to the unprecedented sediment shortage downstream of the cascade reservoirs, especially at Panzhihua, Pinsghan and Yichang. [ABSTRACT FROM AUTHOR]

Abstract: Identifying spatial and temporal patterns in fish movements can reveal the driving factors that govern the behavior of fish in their environment. In this study, we characterized the spatial and temporal occupation of 37 acoustically tagged bigeye scads (Selar crumenophthalmus) in an array of shallow Fish Aggregating Devices (FADs) to clarify the mechanism that leads fish to associate with FADs. A comparison of the number of visits and residence times exhibited by the fish at different FADs revealed a strong variability over the array of FADS, with the emergence of a leading FAD that recorded the majority of visits and retained the fish for a longer period of time. We found diel variability in the residence times, with fish associated at daytime and exploring the array of FADs at nighttime. We demonstrated that this diel temporal pattern was amplified in the leading FAD. We identified a 24-hour periodicity for a subset of individuals associated to the leading FAD, thus suggesting that those fish were able to find this FAD after night excursions. The modeling of fish movements based on a Monte Carlo sampling of inter-FAD transitions revealed that the observed spatial heterogeneity in the number of visits could not be explained through simple array-connectivity arguments. Similarly, we demonstrated that the high residence times recorded at the leading FAD were not due to the spatial arrangement of individual fish having different associative characters. We discussed the relationships between these patterns of association with the FADs, the exploration of the FAD array and the possible effects of social interactions and environmental factors. [Copyright &y& Elsevier]

Abstract: We examined the occurrence patterns of insect pests in paddy fields using a self-organizing map (SOM) and the influence of meteorological factors on these patterns. Data for nine insect pests and three meteorological factors were collected on the Korean nationwide scale from 1992 to 2008. The SOM analysis was based on annual mean densities of each pest species in eight regions. We classified the samples into five clusters (I–V) to display the spatial and temporal changes in the insect pests'' occurrences. Clusters I and II included samples collected before 2000; clusters III and IV included samples collected after 2000. The density of Scotinophara lurida was in the lowest range in clusters I and II, and Lissorhoptrus oryzophilus exhibited higher densities in clusters III and IV. Seasonal temperature, humidity, and precipitation were significantly different among clusters, indicating that these factors play a key role in population dynamics and the occurrence of insect pests. The occurrence area of the insect pests was expected to increase with elevated air temperature influenced by global warming based on the IPCC (Intergovernmental Panel on Climate Change) A1B scenario. This study suggests that gathering data on temporal and spatial variations in pest populations and changes in occurrence rate under the effects of global warming can provide insight into the factors governing the population-environment relationships, as well as the information needed for future pest management. [Copyright &y& Elsevier]

The climate system is a prototypical nonlinear complex system exhibiting nonstationary temporal variation and complicated spatial patterns. One of the ideal locations for studying climate systems is the Qinghai-Tibet Plateau (QTP), which is considered an amplifier of global climate change. In this study, recurrence quantification analysis (RQA) was used to analyze the annual temperature series of 17 stations in different climate zones of the QTP, based on station observation data of daily temperature (minimum, maximum and mean) from 1961 to 2008. Spatial patterns and variation of RQA indices of Determinism (DET) and Kolmogorov (K2) entropy suggested that there are marked differences in temperature pattern in the QTP. Correlation analysis between RQA indices of temperature series and environmental factors, such as topographical variation and Normalized Difference Vegetation Index suggest that both the source and effect of climate complexity are nonlinear. Results of this study indicate that RQA measurement was indeed an efficient approach to analyze the dynamics of a climate system. [ABSTRACT FROM AUTHOR]

Long-term monitoring studies are needed to understand changes in ecosystem status when restoration measures are implemented. A long-term data series (1996-2007) of the Tagus estuary (Portugal) intertidal and subtidal benthic communities was collected in a degraded area where mitigation measures were implemented. Multivariate analysis was used to analyze spatial and temporal patterns in benthic community composition and trends in five benthic community metrics (i.e., taxonomic richness, density, biomass, Shannon-Wiener diversity and the AMBI index) were also examined. The results revealed a clear separation between intertidal and subtidal assemblages, although they had 50% of taxa in common, including the most abundant. Significant positive trends were found for all metrics showing that both intertidal and subtidal communities responded to the restoration measures implemented. Nevertheless, biotic indices need some adaptation before being universally applied to intertidal and subtidal habitats. [ABSTRACT FROM AUTHOR]

Abstract: A Markov-chain transition model (FORSUM) and Monte Carlo simulations were used to simulate the succession patterns and predict a long-term impact of flood on the forest structure and growth in the floodplain of the Upper Mississippi River and Illinois River. Model variables, probabilities, functions, and parameters were derived from the analysis of two comprehensive field surveys conducted in this floodplain. This modeling approach describes the establishment, growth, competition, and death of individual trees for modeled species on a 10,000-ha landscape with spatial resolution of 1ha. The succession characteristics of each Monte Carlo simulation are summed up to describe forest development and dynamics on a landscape level. FORSUM simulated the impacts of flood intensity and frequency on species composition and dynamics in the Upper Mississippi River floodplain ecosystem. The model provides a useful tool for testing hypotheses about forest succession and enables ecologists and managers to evaluate the impacts of flood disturbances and ecosystem restoration on forest succession. The simulation results suggest that the Markov-chain Monte Carlo method is an efficient tool to help organize the existing data and knowledge of forest succession into a system of quantitative predictions for the Upper Mississippi River floodplain ecosystem. [Copyright &y& Elsevier]

Abstract: The widespread loss of oak-hickory forests and the impacts of flood have been major issues of ecological interest concerning forest succession in the Upper Mississippi River (UMR) floodplain. The data analysis from two comprehensive field surveys indicated that Quercus was one of the dominant genera in the UMR floodplain ecosystem prior to the 1993 flood and constituted 14% of the total number of trees and 28% of the total basal area. During the post-flood recovery period through 2006, Quercus demonstrated slower recovery rates in both the number of trees (4%) and basal area (17%). In the same period, Carya recovered greatly from the 1993 flood in terms of the number of trees (11%) and basal area (2%), compared to its minor status before the flood. Further analyses suggested that different species responded to the 1993 flood with varying tolerance and different succession strategies. In this study, the relation of flood-caused mortality rates and DBH, f m (d), can be expressed in negative exponential functions for each species. The results of this research also indicate that the growth functions are different for each species and might also be different between pre- and post-flood time periods. These functions indicate different survival strategies and emergent properties in responding to flood impacts. This research enhances our understanding of forest succession patterns in space and time in the UPR floodplain. And such understanding might be used to predict long-term impacts of floods on UMR floodplain forest dynamics in support of management and restoration. [Copyright &y& Elsevier]

The article discusses the study on the spatial and temporal patterns of break-up and ice-jam flooding in the Mackenzie Delta in Northwest territories. It states that the Mackenzie Delta provides habitat for a range of species but the current hydrology in the Delta lakes are dominated by cryospheric processes. It notes that the backwater levels and discharge at the Mackenzie Delta will determine the physical rationale of the resulting spatial and temporal patterns.

We suggest an ethno-biological approach to analyze the cultural and social drivers of hunting activities and assess sustainability in villages near Makokou, northeast Gabon, based on interviews with hunters, participatory mapping of hunting territories, and daily records of offtakes for 1 yr. Hunting in villages of northeast Gabon is practiced for both local consumption and cash income to cover basic family expenses. There appears to be no clear tendency to abandon subsistence hunting for commercial hunting as in other regions of Africa. Cultural and socioeconomic factors explain the temporal and spatial variation in hunting activities. Hunting increases in the dry season during circumcision ceremonies, when it is practiced mainly at > 10 km from villages, and decreases during the rainy season because most hunters are occupied by other economic activities. Degraded forest such as secondary regrowth supplies 20% of the animals killed and the greatest diversity of species at short distances from villages. Mature forest supplies the species with the greatest commercial value, e.g., red river hog (Potamochoerus porcus), and is the preferred source of meat for traditional ceremonies. In the last 15 yr, hunting patterns have changed rapidly, mainly because of the spread of gun hunting, which had serious implications for the nature of offtakes. Our results suggest that there is potential to allow hunting for resistant species such as blue duiker (Cephalophus monticola) and African brush-tailed porcupine (Atherurus africanus). Other species such as red river hog and small diurnal monkeys require more attention. Specific management systems could be discussed in participatory hunting management plans to identify possible solutions to maintain the population levels of the more critical species. [ABSTRACT FROM AUTHOR]

This study was designed to investigate seasonal changes on food available for benthic consumers in relation to tidal levels and sediment depth in an estuarine beach. The relationships between the biochemical characteristics of sedimentary organic matter and benthic macrofauna were analyzed quarterly over 2 years (from January 1997 to January 1999), in an estuanne soft intertidal zone from the NW coast of Spain (42°64′04″N, 8°88′36″W). Sediment samples were collected to provide a two-dimensional view of macroinfauna distribution in the intertidal zone and its relationship with the quantity and quality of the organic matter. The nutritional value of organic matter (i.e., lipid, protein, and carbohydrate) and the content of chlorophyll a of the sediment were measured. Macrofaunal assemblages and food availability in the sediment were studied at three tidal levels on the shore: two intertidal and one supratidal. Macroinfauna and biochemical compounds showed a clear vertical stratification with the highest macrofaunal abundance at the superficial layer of the sediment, where redox potential discontinuity was also observed. Crustaceans were found mainly inhabiting the supratidal level of the estuarine beach, while polychaetes and mollusks occupied the intertidal level. Food availability, measured as biopolymeric carbon, and also chlorophyll a from the sediment were better related to macroinfauna abundance, biomass, and abundance of main taxonomic groups. Macrofauna assemblages showed particular distribution in both vertical and horizontal ranges suggesting specific preferences to several abiotic factors. No clear seasonal pattern was found in macrofauna and sedimentary organic characteristics suggesting that macrofaunal assemblages are controlled by complex and unpredictable factors, including small-scale changes in substrate and hydrological characteristics. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we have monitored 12 stations to study the effects caused by natural, marine and anthropogenic activities on water quality in Daya Bay, China. Results show that the N:P ratios are 71.54, 41.29, 81.50 and 98.27 in winter, spring, summer and autumn, respectively. Compared with the data of the past 20 years, the atomic N:P ratios have increased, indicating increased potential for P limitation; the atomic Si:N ratios have decreased; the nutrient structure has substantially changed over a period of 20 years. These findings show that the nutrient structure may be related to anthropogenic influence. The data matrix has been built according to the results, which were analyzed by principal component analysis (PCA). This analysis extracted the first four principal components (PC), explaining 73.58% of the total variance of the raw data. PC1 (25.53% of the variance) is associated with temperature, salinity and nitrate. PC2 (21.64% of the variance) is characterized by dissolved oxygen and silicate. PC3 (15.91% of the variance) participates mainly by nitrite (NO2-N) and ammonia (NH4-N). PC4 explaining 10.50% of the variance is mainly contributed by parameters of organic pollution (dissolved oxygen, 5-day biochemical oxygen demand and chemical oxygen demand). PCA has found the important factors that can describe the natural, marine and anthropogenic influences. Temperature and salinity are important indicators of natural and marine characters in this bay. The northeast monsoons from October to April and southwest monsoons from May to September have important effects on the waters in Daya Bay. It has been demonstrated that anthropogenic activities have significant influence on nitrogen form character. In spatial pattern, a marine aquaculture area and a non-aquaculture area are widely identified by the scores of stations. In seasonal pattern, dry and wet season characters have been demonstrated. [Copyright &y& Elsevier]

Abstract: Sheep herd sustainability in Patagonia is limited by reproductive efficiency. As the herds graze on natural vegetation year round, efficiency is constrained by biophysical factors. Our aim was to characterize the environmental controls over effective lambing rate in northwest Patagonia. We related remotely sensed data [surface temperatures and Normal Difference Vegetation Index (NDVI), a surrogate for forage availability] and climatic information to lambing rates. A spatial model explained 63% of the variability in mean lambing rate, based on mean annual NDVI and mean spring surface temperature. The relative inter-annual variability in lambing rates was of similar magnitude to that of annual NDVI. Both lambing rate and NDVI were less variable than climatic factors. Two regional temporal models explained approximately 25% of the variability, based on NDVI values representative of ewes’ nutrition during late gestation and lambing. These models predicted, with 65% and 76% accuracy respectively, the occurrence of better-than-average and worse-than-average yearly lambing rates. These results provided insights into the factors limiting reproduction, and they form the basis for important decision tools for ranch managers. Prediction of lambing rates based on remotely sensed data will reduce the uncertainty and risk in sheep production, increasing the economic sustainability of sheep production. [Copyright &y& Elsevier]

'Greenhouse gases', especially carbon dioxide, are intimately connected to climate change. To understand the future evolution of the climate system and find ways to manage the concentration of atmospheric carbon dioxide, the processes and feedbacks that drive the carbon cycle must first be understood. However, our current knowledge of spatial and temporal patterns is uncertain, particularly over land and in regions of potentially high sensitivity to change like the boreal zone. The European Space Agency (ESA) GLOBCARBON project aims to generate fully calibrated estimates of at-land products quasi-independent of the original Earth Observation source for use primarily in Dynamic Global Vegetation Models, but also as a contribution to the Global Carbon Project, a cooperation between the International Geosphere Biosphere Programme, International Human Dimensions Programme and the World Climate Research Programme to aid understanding of global carbon cycling. The service will feature estimation of global burned area, the fraction of absorbed photosynthetically active radiation (∫APAR), leaf area index (LAI) and Vegetation Growth Cycle. The demonstrator will focus on ten complete years, from 1998 to 2007 when overlap exists between ESA Earth Observation sensors and others that are synergistic. However, the system will be flexible so that it is not dependent on any single satellite sensor and therefore can be retrospectively applied to existing archives and used with future satellite sensors. [ABSTRACT FROM AUTHOR]

Spatial and temporal aspects of recruitment play a central role in plant population and community dynamics and have important basic and applied implications. Here we summarize and discuss the results from studies of spatiotemporal dynamics of recruitment stages (seeds-seedlings-saplings) in Aleppo pine (Pinus halepensis) throughout the species' native range. Seed release is induced either by fire (pyriscence) or by drying atmospheric conditions (xeriscence), each generating a distinct temporal pattern. In both cases most seeds travel relatively short distances (<30 m). Pyriscence is not expected to promote long-distance seed dispersal, but xeriscence is associated with relatively strong winds that can transport seeds over 1 km and more, as predicted by a new mechanistic dispersal model. In the absence of fire, seed survival increases with distance from adults because of higher competition with adults and sibs and higher seed predation near the seed sources. New data provide further evidence for such distance-dependent seed predation and also show that predation rates vary among habitats and are lowest in times of high seed abundance. The resulting recruitment patterns in the absence of fire are characterized by rapid spread and complex spatiotemporal dynamics that are fairly unpredictable and give rise to variable age structure. In contrast, the spatial pattern of the first post-fire generation is highly predictable because it explicitly replicates the spatial pattern of the pre-fire population. Unlike fire-free regeneration in which multiple factors operating at various stages are likely to be important, post-fire regeneration is governed by a fairly specific set of factors (the chemical properties of ash) operating during a specific stage (saplings) and at a specific location (the canopy projection of large burned pines). Post-fire forests are therefore even-aged and have predictable spatiotemporal dynamics. Most studies of Aleppo pine recruitment have focused on the seedling and sapling stages and on post-fire regeneration; we call for greater attention to the seed stage and to more extensive sampling of all recruitment stages in both space and time. [ABSTRACT FROM AUTHOR]

This study aims at investigating the spatial and temporal variability of the seasonal rainfall over Sinai Peninsula, Egypt, relying on rainfall data taken from gridded data of four gauge stations for 35 years. Moreover, this study determines the teleconnection between the seasonal rainfall and equatorial Pacific sea surface temperature (El Niño SST) over El Arish and Wadi Watir. Due to non-stationary characteristics of Sinai rainfall, this study employs the Wavelet Principal Component Analysis (WPCA) technique. According to the spatial characteristics of January, February and March (JFM), and October, November and December (OND) rainfall seasons, Sinai Peninsula can be divided into two zones: northern zone along the coastal area of the Mediterranean, and central-southern zone. The WPC signals showed that the dominant frequency period of Sinai rainfall ranged 2–8 years. Using Wavelet Coherence (WC), the study found a strong teleconnection between the seasonal rainfall over El Arish and Wadi Watir as well and El Niño SST at a 3-month lead time. The study results will improve the forecasting skills of flash water events over Sinai Peninsula, particularly, the northern zone in order to take suitable precautions to eliminate their impacts. • Sinai Peninsula rainfall delineated into two zones; northern zone, and southern-central zone. • The dominant frequency cycle of Sinai rainfall ranges between 2 and 8 years. • Teleconnection to Sinai seasonal rainfall with El Niño SST at a 3-month lead time. [ABSTRACT FROM AUTHOR]

• Empirical models were applied to quantify solar radiation and photovoltaic power. • A large network of observations was used to provide forcing inputs. • The newly developed empirical model can accurately estimate global solar radiation. • The annual photovoltaic power exhibited a significantly declining trend. • Western China is an optimal location for solar photovoltaic power plants. Global solar radiation (R s) is a key parameter for determining the energy yields of solar photovoltaic (PV) systems. However, long-term R s data are not available in most regions of China, impeding the management and development of PV systems. In this study, a novel model for estimating R s was developed and coupled with a PV power model and inverse distance weighting model to generate high-resolution R s and PV power data over China. A large network of observations was used to provide forcing inputs (daily observations from 1961 to 2018, from 2123 meteorological stations). The spatiotemporal patterns of R s and PV power in China were further quantified. The results indicate that the newly developed R s model accurately represents the decadal variability of R s in China during 1961–2018. Annual potential PV power exhibited a significantly decreasing trend from 1961 to 2018, with a significant decrease from 1961 to 1991 (−0.35 ± 0.06 kWh m−2 yr−1, p < 0.01) and non-significant decrease from 1992 to 2018 (−0.14 ± 0.12 kWh m−2 yr−1, p > 0.05). Owing to air quality improvements in the future, the potential PV power may increase over China, leading to large economic benefits. Western China is favored for its abundant PV power, whereas central and eastern China are the least favorable for PV power generation. Thus, the western part of China, with its excellent geographical potential, is an optimal location for the installation of solar PV power plants. Our findings provide practical information to solar energy industries, and can help in energy structure transitions, meeting the energy demand and contributing to carbon neutrality. [ABSTRACT FROM AUTHOR]

We suggest an ethno-biological approach to analyze the cultural and social drivers of hunting activities and assess sustainability in villages near Makokou, northeast Gabon, based on interviews with hunters, participatory mapping of hunting territories, and daily records of offtakes for 1 yr. Hunting in villages of northeast Gabon is practiced for both local consumption and cash income to cover basic family expenses. There appears to be no clear tendency to abandon subsistence hunting for commercial hunting as in other regions of Africa. Cultural and socioeconomic factors explain the temporal and spatial variation in hunting activities. Hunting increases in the dry season during circumcision ceremonies, when it is practiced mainly at > 10 km from villages, and decreases during the rainy season because most hunters are occupied by other economic activities. Degraded forest such as secondary regrowth supplies 20% of the animals killed and the greatest diversity of species at short distances from villages. Mature forest supplies the species with the greatest commercial value, e.g., red river hog (Potamochoerus porcus), and is the preferred source of meat for traditional ceremonies. In the last 15 yr, hunting patterns have changed rapidly, mainly because of the spread of gun hunting, which had serious implications for the nature of offtakes. Our results suggest that there is potential to allow hunting for resistant species such as blue duiker (Cephalophus monticola) and African brush-tailed porcupine (Atherurus africanus). Other species such as red river hog and small diurnal monkeys require more attention. Specific management systems could be discussed in participatory hunting management plans to identify possible solutions to maintain the population levels of the more critical species.

Volunteered geographic information (VGI) has great potential to reveal spatial and temporal dynamics of geographic phenomena. However, a variety of potential biases in VGI are recognized, many of which root from volunteer data contribution activities. Examining patterns in volunteer data contribution activities helps understand the biases. Using eBird as a case study, this study investigates spatial and temporal patterns in data contribution activities of eBird contributors. eBird sampling efforts are biased in space and time. Most sampling efforts are concentrated in areas of denser populations and/or better accessibility, with the most intensively sampled areas being in proximity to big cities in developed regions of the world. Reported bird species are also spatially biased towards areas where more sampling efforts occur. Temporally, eBird sampling efforts and reported bird species are increasing over the years, with significant monthly fluctuations and notably more data reported on weekends. Such trends are driven by the expansion of eBird and characteristics of bird species and observers. The fitness of use of VGI should be assessed in the context of applications by examining spatial, temporal and other biases. Action may need to be taken to account for the biases so that robust inferences can be made from VGI observations. [ABSTRACT FROM AUTHOR]

The study determined water temperature trends of rivers in Poland in the period 1971–2015, and also their spatial and temporal patterns. The analysis covered daily water temperature of 53 rivers recorded at 94 water gauge stations and air temperature at 43 meteorological stations. Average monthly, annual, seasonal and maximum annual tendencies of temperature change were calculated using the Mann–Kendall (M–K) test. Regional patterns of water temperature change were determined on the basis of Ward's hierarchical grouping for 16 correlation coefficients of average annual water temperature in successive 30-year sub-periods of the multi-annual period of 1971–2015. Moreover, regularities in monthly temperature trends in the annual cycle were identified using 12 monthly values obtained from the M–K Z test. The majority of average annual air and water temperature series demonstrate statistically significant positive trends. In three seasons: spring, summer and autumn, upward tendencies of temperature were detected at 70%–90% of the investigated water gauges. In 82% of the analysed rivers, similarity to the tendencies of change of monthly air temperature was concluded, with the climatic factor being recognised as of decisive importance for the changes in water thermal characteristics of the majority of rivers in Poland. In the winter months, positive trends of temperature were considerably weaker and in general statistically insignificant. On a regional scale, rivers with a quasi-natural thermal regime experienced temperature increases from April to November. In the other cases, different directions of change in river water temperature (RWT) were attributed to various forms of human impact. It was also found that for the majority of rivers the average annual water temperature in the analysed 30-year sub-periods displayed upward trends, statistically significant or close to the significance threshold. Stronger trends were observed in the periods after 1980, while a different nature of water temperature change was detected only in a couple of mountainous rivers or rivers transformed by human impact. In the beginning of the analysed period (1971–2015), the average annual water temperature of these rivers displayed positive and statistically significant trends, while after 1980 the trends were negative. The detected regularities and spatial patterns of water temperature change in rivers with a quasi-natural regime revealed a strong influence of climate on the modification of their thermal regime features. Rivers characterised by a clearly different nature of temperature change, both in terms of the direction of the tendencies observed and their statistical significance, were distinguished by alterations of water thermal characteristics caused by human activity. The results obtained may be useful in optimising the management of aquatic ecosystems, for which water temperature is a significant indicator of the ongoing environmental changes. [ABSTRACT FROM AUTHOR]

• Artificial neural networks model simulated the effects of the precipitation and temperature on agricultural drought. • The patterns of precipitation and temperature distribution greatly affected agricultural drought, with the precipitation effect being more pronounced. • The precipitation thresholds were identified to detect agricultural drought in critical months of crop growth. • The modeling framework has a wide applicability for other regions in drought simulation. Agricultural drought is one of the most frequent and widespread natural disasters occurring in China. Drought is associated with hydrological and meteorological conditions that lead to water-deficient vegetation, which has a negative effect on agricultural activities. The monitoring of droughts, as well as early-warning and timely information, is significant for crop production and food security. However, the spatial and temporal patterns of precipitation and temperature have rarely been reported when monitoring the agricultural drought loss rate on a national scale. In this study, we analyzed the spatial and temporal patterns of drought based on model simulation. An artificial neural network (ANN) model for drought warning was developed using monthly temperature and precipitation data from 1949 to 2015. Our results demonstrated that the agricultural drought loss rate can be simulated in most agricultural areas of China. Our ANN model simulation revealed that the areal percentages of precipitation and temperature are strongly correlated with agricultural drought, with the agricultural drought loss rate exhibiting greater sensitivity to precipitation than temperature. We suggest that the spatial and temporal patterns of precipitation are useful for capturing drought warning signals. The precipitation thresholds play an important role in detecting agricultural drought in critical months or seasons of crop growth in different regions. This study presents a framework and reference for drought monitoring in the regions and countries facing frequent agricultural drought. [ABSTRACT FROM AUTHOR]

Information about factors that affect patterns of use by bike share members is needed to manage systems effectively and equitably. Recent research into the patterns of use by members across heterogeneous neighborhoods indicates that neighborhood characteristics as well as built environment characteristics may be associated with use. We use 2017 data on trips taken by 30-day and annual members of the Nice Ride Bike Share System in Minneapolis-St. Paul and examine the associations between user behavior and socio-demographic characteristics at the Census block group (CBG) level where members live. We estimate linear mixed-effects models and multinomial logistic models to analyze the associations of neighborhood socio-demographic characteristics with, respectively, (1) the frequency and duration of weekday and weekend trips by members and (2) the temporal and spatial patterns of their trips. Our results show that, after controlling for station accessibility, nearby bike infrastructure, the built environment, gender, and age, members who reside in minority-concentrated and lower socio-economic status (SES) neighborhoods use bike share more frequently, take trips at more varied times-of-day and across days-of-week, and have more frequently-used origin-destination pairs of stations. A limitation of our analysis is that patterns of use of casual users are not investigated. Our findings have implications for efforts to serve members in neighborhoods with higher concentrations of minorities and residents of lower SES and illustrate the need for more detailed surveys of members to obtain additional information about individual characteristics associated with behaviors of bike share users. • Explores temporal and spatial use patterns of BSS members (30-day, annual) in Twin Cities. • Examines the association between neighborhood socio-demographics and BSS members' use behaviors. • Reveals disparities in use behaviors of BSS members living in neighborhoods with different socio-demographics. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau is one of the most vulnerable areas to extreme precipitation. In recent decades, water cycles have accelerated, and the temporal and spatial characteristics of extreme precipitation have undergone dramatic changes across the Tibetan Plateau, especially in its various ecosystems. However, there are few studies that considered the variation of extreme precipitation in various ecosystems, and the impact of El Niño-Southern Oscillation (ENSO), and few researchers have made a quantitative analysis between them. In this study, we analyzed the spatial and temporal pattern of 10 extreme precipitation indices across the Tibetan Plateau (including its four main ecosystems: Forest, alpine meadow, alpine steppe, and desert steppe) based on daily precipitation from 76 meteorological stations over the past 30 years. We used the linear least squares method and Pearson correlation coefficient to examine variation magnitudes of 10 extreme precipitation indices and correlation. Temporal pattern indicated that consecutive wet days (CWD) had a slightly decreasing trend (slope = −0.006), consecutive dry days (CDD), simple daily intensity (SDII), and extreme wet day precipitation (R99) displayed significant increasing trends, while the trends of other indices were not significant. For spatial patterns, the increasing trends of nine extreme precipitation indices (excluding CDD) occurred in the southwestern, middle and northern regions of the Tibetan Plateau; decreasing trends were distributed in the southeastern region, while the spatial pattern of CDD showed the opposite distribution. As to the four different ecosystems, the number of moderate precipitation days (R10mm), number of heavy precipitation days (R20mm), wet day precipitation (PRCPTOT), and very wet day precipitation (R95) in forest ecosystems showed decreasing trends, but CDD exhibited a significant increasing trend (slope = 0.625, P < 0.05). In the other three ecosystems, all extreme precipitation indices generally exhibited increasing trends, except for CWD in alpine meadow (slope = −0.001) and desert steppe (slope = −0.005). Furthermore, the crossover wavelet transform indicated that the ENSO had a 4-year resonance cycle with R95, SDII, R20mm, and CWD. These results provided additional evidence that ENSO play an important remote driver for extreme precipitation variation in the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Spatial and temporal variations in colored dissolved organic matter (CDOM) are of great importance to understanding the dynamics of the biogeochemical properties of water bodies. This study proposed a remote sensing approach for estimating CDOM concentrations (CCDOM) based on in situ observations from the Bohai Sea (BS) and the North Yellow Sea (NYS). Cross-validation demonstrated that the accuracy of the CDOM algorithm is R2 = 0.78, APD = 15.9%, RMSE = 0.92 (ppb). The CDOM algorithm was applied to estimate the 14-year (2003–2016) sea surface CCDOM in the BS and NYS areas using Moderate Resolution Imaging Spectroradiometer (MODIS) monthly products. The results showed a significant fluctuation in CDOM variations on a long-term scale. The highest values of CDOM were observed in the BS, the middle values were observed in the Bohai Strait, and the lowest values were observed in the NYS. Seasonal variations were observed with long-lasting high CDOM values from June to August in coastal waters, while relatively low values were observed in the NYS in the summer. In the spring and fall, a distinct increase appeared in the NYS. High CDOM values in the nearshore coastal waters were mostly related to terrestrial inputs, while CDOM in the offshore regions was mainly due to autochthonous production. Furthermore, ocean currents played an important role in the variations in CDOM in the BS and NYS areas, especially for variations in CDOM in the Bohai Strait. [ABSTRACT FROM AUTHOR]