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Given the rapid urbanization, the spatial patterns of green spaces in urban environments have undergone significant changes. This study aims to assess the quantitative changes and spatial patterns of green spaces in the city of Salmas using a landscape ecology approach. To achieve this, green space maps of Salmas from Google Earth Engine imagery for the years 2008, 2015, and 2022 were extracted. The urban development of Salmas over the 15-year period was then evaluated. Landscape metrics for structural connectivity were calculated using Fragstats 4.2.1, and functional connectivity indices using Confer Sensinode 2.6 at distances of 100, 250, 500, 750, 1000, 1500, 2000, and 2500 m in all study periods. The results indicated that in Salmas, the green spaces experienced a relatively unfavorable trend in terms of composition, distribution, and spatial arrangement. Over the study period, green space patches underwent a process of degradation concerning their extent, connectivity, and spatial distribution. Moreover, the urban green space per capita in 2008 in Salmas was 8.09 m2/capita, which did not significantly differ from the national standard (12 m2/capita). However, by 2022, with the population and area increase in Salmas, the urban green space per capita decreased to 5.78 m2. Structural connectivity results revealed insufficient connectivity between urban green space patches in Salmas. Functional connectivity analysis demonstrated a decreasing trend in most of the examined indices. Only the dBC_PC index showed a fluctuating trend from 2008 (4.73) to 2022 (5.22), indicating the stability of significant green space patches in Salmas. The overall analysis of urban green spaces in Salmas indicated a decreasing trend in patch density. The reduced creation of green space patches in recent periods implies a decline in the spatial relationships of urban green spaces. Given the shortage of green spaces in studied small size city, planning to increase the area and urban green space per capita is essential. [ABSTRACT FROM AUTHOR]

Our study aimed to assess the impacts of varying forest gap sizes on the density, growth, and spatial patterns of seedlings and saplings in spruce (Picea asperata) forests in the Saihanba region, Hebei Province, China. Twenty-four forest gaps were surveyed and categorized into six classes based on the gap size. A one-way ANOVA was used to compare differences in the density, height, and ground diameter of seedlings and saplings among six gap classes. Ripley's K function was used to explore the spatial patterns of regeneration establishment in each class. The findings of our study indicated that the forest gap size did not significantly influence the density of seedlings or the ground diameter growth of saplings, whereas it significantly influenced the height growth of saplings. In smaller gaps, natural regeneration occurred primarily in the gap edges. As the gap size increased, the natural generation began to shift from the edge areas to the gap centers. Large forest gaps had the highest percentages of random distribution patterns across all spatial scales. Aggregated distributions were observed at distances less than 1 m in all gap size classes, whereas uniform distributions tended to occur in the small gaps at distances of 2–4 m. Our findings indicated that larger forest gaps, ranging from 60 to 120 m2, were more conducive to spruce regeneration. The results can inform the development of targeted strategies for understory afforestation and the artificial promotion of natural regeneration in spruce forests. [ABSTRACT FROM AUTHOR]

This work focused on Chiang Mai Province, Thailand, had 2 targets which were 1) to analyse spatial distribution patterns of hotspot and 2) to analyse a relationship between hotspot and vegetation indices in the area. The hotspots data of 2016 - 2020 which had a significant level > 70% were gathered from MODIS satellite images, was provided by Fire Information for Resource Management System (FIRMS). An analyse method was performed by Nearest Neighbour Index (NNI) with Moran’ s I to present spatial distribution patterns and density of hotspot. Analysis of Getis - Ord Gi* statistic was for identify heat of hotspot comparing with surrounding area. Moreover, vegetation indices values (Normalized Difference Vegetation Index: NDVI, Soil Adjustment Vegetation Index: SAVI and Normalized Difference Water Index: NDWI) was examined by satellite images of the same period from Landsat 8 OLI to analyse a relationship between hotspot and each vegetation index. The results illustrated that there were different number of hotspots over 5 studying years, especially in 2016 which had the most hotspot. The spatial distribution of hotspot patterns was classified as clustered type (Getis - Ord Gi* statistic with Z-Score > 1.96) with different hotspot density in each year. The area which had high heat was found in upper and west area with medium to high hotspots density. The hotspot and NDVI had relationship in contrast by a correlation coefficient value at -.887 (r = -.887) with a significant level at .05. However, SAVI and NDWI had no relationship with hotspot.

Trees on agricultural fields can have a positive or negative impact on weed seedbank (WSB) due to diverse environmental and soil characteristics. Therefore, soil samples were drawn in six cropping systems [two agroforest systems (AFS): guava, mango; three horticulture systems (HCS): guava, mango, Indian gooseberry; and annual crop system (ACS)] at two landscape positions (lowland and upland) and two soil depths (0-15 cm and 15-30 cm) using factorial randomised block design each replicated three times. Results showed that guava-AFS had the highest WSB of different categories in general and individual weed species in particular, except for Eragrostis pilosa and Dactyloctenium aegyptium. Simultaneously, guava-AFS also showed the maximum Shannon-Weaver, species richness and Simpson index and was low in Whittaker statistics (βW). The species evenness varied non-significantly with the cropping systems. Similarly, the landscape position had no discernible effect on any weed diversity indices; however lowland landscape position was dominated by Cyperus spp. and E. pilosa, while the upland by Phyllanthus niruri. Furthermore, with the exception of βW, the WSB and diversity indices were found to be higher on the topsoil (0-15 cm). Our study establishes that the AFS system in the semi-arid sub-tropics has a more diverse WSB indicating a healthy system, as opposed to HCS, which has a dominance of certain weed species, opening the door for more severe infestation of invasive weed species.

The spatial allocation of medical resources is closely related to population health outcomes. Health workforce shortage and maldistribution represent significant challenges for health systems functioning in many countries. Romania registers the lowest physicians per patient ratio in the European Union (EU). Despite the increasing number of medical graduates, shortages have become more critical over the past two decades with both out-migration of health professionals and intra-country disparities between large cities and rural areas or between primary and speciality care. Considering these variances in health workforce supply, it is crucial to identify areas with particularly low human resources. This paper focuses on a critical determinant of geographic access to healthcare, namely the availability of health professionals. We identified and analysed the patterns of physicians' geographic distribution at the lowest spatial level, pointing out their imbalances and factors interrelated with territorial disparities. Gini coefficient calculation and Moran's I index provided strong evidence for increasing divergences in this distribution. Furthermore, the analysis of the physician/population ratio spatial patterns revealed two areas of opposite clusters on the west-east axis: one of positive spatial aggregation in the west and one negative in the east. Geographical imbalances in the health workforce distribution have adverse effects, particularly on the public healthcare sector. To address the issue of territorial imbalances, we considered that the maldistribution of physicians is contextually created and might cause several dysfunctions in the healthcare system: normative (the dilemma of dual practising in the public and private sector simultaneously), educational (specialized training, enrolment, and logistics), and social (emigration of physicians and retention policies). Therefore, for the effective functioning of its healthcare system, Romania still needs to implement policies to retain medical graduates and reduce physician outflows. Also, specific strategies regarding the size, structure and distribution of the physician workforce are required to alleviate issues related to access to care. [ABSTRACT FROM AUTHOR]

Brick kilns constitute one of the major sources of environmental degradation in Pakistan. The present study was conducted to determine the soil quality and total suspended particulates (TSPs) around the brick kilns and assess the health effects on brick kiln workers. Four brick kilns were selected, two each at Sheikhupura and Pattoki city. The soil quality was assessed by analyzing pH, electrical conductivity, moisture content, nitrogen, phosphorus, potassium content, and heavy metal concentration while TSPs were measured by hand-held Microdust Pro Real time monitor. Average TSP concentration around brick kilns at Sheikhupura and Pattoki ranged between 1100 and 1200 µg/m3 and between 550 and 600 µg/m3 respectively which exceeded the Punjab Ambient Air Standards. The soil was slightly acidic (Sheikhupura: average pH = 6.41; Pattoki: average pH = 6.6) while all other analyzed parameters, except heavy metals, were lower than the required FAO Standards for good quality agriculture soil. Heavy metal accumulation in soil samples followed the general order zinc (Zn) > chromium (Cr) > nickel (Ni) > manganese (Mn) > cadmium (Cd) > copper (Cu). For assessment of occupational health and safety issues, all 440 brick kiln workers from the study areas were interviewed. Mostly, brick kiln workers suffered from chronic back pain (84%), skin issues (80.5%), dry cough (72.9%), common cold (46.1%), and shortness of breath (17.1%). The vulnerability risk varied with the nature of the work as workers engaged in brick baking were more vulnerable to respiratory issues than were those in molding task. The study concludes that brick kilns are a source of increased TSP, deteriorated surrounding soil quality, and impaired worker health. It is necessary to regulate these activities and implement requisite health and safety measures. [ABSTRACT FROM AUTHOR]

Our study aimed to assess the impacts of varying forest gap sizes on the density, growth, and spatial patterns of seedlings and saplings in spruce (Picea asperata) forests in the Saihanba region, Hebei Province, China. Twenty-four forest gaps were surveyed and categorized into six classes based on the gap size. A one-way ANOVA was used to compare differences in the density, height, and ground diameter of seedlings and saplings among six gap classes. Ripley’s K function was used to explore the spatial patterns of regeneration establishment in each class. The findings of our study indicated that the forest gap size did not significantly influence the density of seedlings or the ground diameter growth of saplings, whereas it significantly influenced the height growth of saplings. In smaller gaps, natural regeneration occurred primarily in the gap edges. As the gap size increased, the natural generation began to shift from the edge areas to the gap centers. Large forest gaps had the highest percentages of random distribution patterns across all spatial scales. Aggregated distributions were observed at distances less than 1 m in all gap size classes, whereas uniform distributions tended to occur in the small gaps at distances of 2–4 m. Our findings indicated that larger forest gaps, ranging from 60 to 120 m2, were more conducive to spruce regeneration. The results can inform the development of targeted strategies for understory afforestation and the artificial promotion of natural regeneration in spruce forests.

Trees on agricultural fields can have a positive or negative impact on weed seedbank (WSB) due to diverse environmental and soil characteristics. Therefore, soil samples were drawn in six cropping systems [two agroforest systems (AFS): guava, mango; three horticulture systems (HCS): guava, mango, Indian gooseberry; and annual crop system (ACS)] at two landscape positions (lowland and upland) and two soil depths (0-15 cm and 15-30 cm) using factorial randomised block design each replicated three times. Results showed that guava-AFS had the highest WSB of different categories in general and individual weed species in particular, except for Eragrostis pilosa and Dactyloctenium aegyptium. Simultaneously, guava-AFS also showed the maximum Shannon-Weaver, species richness and Simpson index and was low in Whittaker statistics (ßW). The species evenness varied non-significantly with the cropping systems. Similarly, the landscape position had no discernible effect on any weed diversity indices; however lowland landscape position was dominated by Cyperus spp. and E. pilosa, while the upland by Phyllanthus niruri. Furthermore, with the exception of ßW, the WSB and diversity indices were found to be higher on the topsoil (0-15 cm). Our study establishes that the AFS system in the semi-arid sub-tropics has a more diverse WSB indicating a healthy system, as opposed to HCS, which has a dominance of certain weed species, opening the door for more severe infestation of invasive weed species. [ABSTRACT FROM AUTHOR]

Aim: Mangrove forests are important coastal wetlands for the blue carbon budget and play a significant role in mitigating global climate change. However, spatial patterns of carbon stocks in mangrove forests on an island scale have not been quantified owing to methodological limitations and lack of understanding of controlling factors. We took the entire Hainan Island as a case study and aimed to carry out a comprehensive investigation of the spatial patterns and driving factors of carbon stocks in mangrove forests. Location: Southern China. Time period: 2017–2020. Major taxa studied: Mangrove forest. Methods: The upscaling method combined with field surveys and Sentinel‐2 imagery analysis were used to compare different models for optimization of mangrove ecosystem carbon stock estimations. We also used structural equation modelling (SEM) to evaluate the factors driving the distributional patterns of mangrove carbon stocks on an island scale. Results: The current total mangrove carbon stock of the entire Hainan Island was estimated to be 703,181 Mg C (with a mean density of 192 Mg C/ha), with the above‐ and below‐ground carbon stocks averaging at 44.7 and 147.3 Mg C/ha, respectively. The mangrove carbon storage in the north‐eastern region of the island was the highest and in the west region the lowest. Sediment nitrogen content and plant species diversity had the most positive driving effects on the distribution of total carbon stock for Hainan Island mangroves. Main conclusions: The combination of field surveys and Sentinel‐2 imagery analysis can be applied to regional‐scale estimations of carbon stocks for mangrove forests. Spatial pattens of mangrove carbon stocks vary among locations on Hainan Island, and soil nutrient (especially nitrogen) availability is the dominant factor regulating carbon stock variations along the land‐to‐sea gradient. Our findings have significant implications for better understanding the distribution of mangrove carbon stocks and quantification of the global blue carbon budget. [ABSTRACT FROM AUTHOR]

As a critical transportation infrastructure, high-speed rail (HSR) greatly enhances accessibility and shortens the spatial-temporal distance among cities. It is well documented that HSR significantly impacts regions and cities’ economic development and spatial structure. The proportion and frequency of business passenger trips are increasing yearly, and the demand for “station as the final destination” is becoming more and more prominent. Given the pivotal role of the design and construction of HSR station areas in achieving “station as the final destination,” the study of their development characteristics and patterns has important implications for urban planning. Previous studies have focused extensively on the macro impact of the HSR operation on regional economies, urban industries, and tourism development, whereas only a few were conducted at the station level. Furthermore, the business-commercial agglomeration effects of the HSR operation on the development and construction of station areas have neither been studied nor accurately measured. To fill this gap, we first constructed a panel data set consisting of the point of interest (POI) data, China City Statistical Yearbook data, and the HSR station operation data from 2012 to 2017. Next, we developed difference-in-differences (DID) models to decipher the impact of the HSR operation on the station-level business and commercial agglomeration. The results show that the HSR operation has increased the business-commercial agglomeration index (BCAI), the commercial agglomeration index (BAI), and the business agglomeration index (CAI) by 28.3%, 29%, and 21.3%, respectively. In other words, the HSR operation has significant business-commercial agglomeration effects in the station area, and the agglomeration effect size of business is more extensive than that of commerce. Interestingly, the BCAI grew slowly in the first 3 years after the HSR operation but started to rise much faster from the fourth year, which HSR’s catalytic effects can explain. The results also reveal that the business-commercial agglomeration effects have a clear spatial threshold as the BCAI tends to decrease from 1500 m to 3000 m away from HSR stations. The plausibility of the results has been confirmed by the parallel trend, placebo, and robustness tests.

Background: The previous attempts for pT2 substaging of prostate cancer (PCa) were insufficient in providing prognostic subgroups and the search for new prognostic parameters to subcategorize pT2 PCa is, therefore, needed. Therefore, the current study investigated the association between tumor distribution patterns and the biochemical recurrence (BCR)-free survival rate in pT2pN0R0 PCa. Methods: Following radical prostatectomy, the anatomical distribution of PCa in 743 men with pT1-pT3pN0 disease was analyzed to determine 20 types of PCa distribution patterns. Then, 245 men with pT2pN0R0 PCa was considered for prognostic evaluation with a mean follow-up period of 60 months. The spatial distribution patterns of PCa were evaluated using a cMDX©-based map model of the prostate. An analysis including 552,049 comparison operations was performed to assist in the evaluation of the similarity levels of the distribution patterns. A k-mean cluster analysis was applied to determine groups with similar distribution patterns. A decision-tree analysis was performed to divide these groups according to frequency of BCR. The BCR-free survival rate was analyzed using Kaplan–Meier curves. Predictors of progression were investigated using a Cox proportional hazards model. Results: BCR occurred in 8.2% of the 245 men with pT2pN0R0 PCa. The median time of recurrence was 60 months (interquartile range [IQR]: 42–77). In univariate and multivariate analyses, the prostate volume and the distribution patterns were independent predictors for BCR, whereas the sub-staging of pT2 tumors, Gleason grading, prostate-specific antigen (PSA) level, and relative tumor volume were not. In the patients with pT2pN0R0 disease, PCa distribution patterns with the apical involvement were significantly associated with the risk of BCR (P = 0.001). Conclusion: The spread tumor patterns with the apical involvement are associated with a high-risk of BCR in the pT2 tumor stage. The vertical tumor spread could be considered in developing improved prognostic pT2 sub-categories. [ABSTRACT FROM AUTHOR]

The availability of safe drinking water is imperative for healthy life but access to safe drinking water has become a major problem around the world, especially in developing countries such as Pakistan. The present study aimed to: assess the suitability of groundwater for potable use in Gujranwala district, Pakistan; examine the spatial distribution patterns of water quality parameters; and to identify the prevalence of waterborne diseases among locals and health risks to humans due to the consumption of groundwater. Eighty drinking water samples were collected from different areas of Gujranwala and analyzed following Standard American Public Health Association methods. A questionnaire survey related to the incidence of waterborne diseases in the area was also carried out. The averaged water quality index (AWQI) was computed using ArcGIS 10.3 model builder. The AWQI map indicated that the water quality was generally suitable for potable use with regard to its physiochemical parameters. However, 97.5% water samples were found to be bacteriologically contaminated. The mean concentration of metals in drinking water showed a decreasing trend in the order Cr > Cu > Zn > As > Co > Ni > Cd. Health risk index (HRI) was also calculated for exposure to metal concentration. For Cd, one sample showed an HRI value > 1 i.e. 1.59 and 1.36 for child and adult, respectively, while HRI for As showed values > 1 varying between 0.5 and 11 for child, and 0.4 and 9.6 for adults. For other metals HRIs was less than 1 (considered to be safe for the consumers). The study concludes that groundwater quality of study areas of Gujranwala has mostly deteriorated. [ABSTRACT FROM AUTHOR]

How microbes respond to substantial and increasing anthropogenic disturbance remains an open question in river systems. We tested the hypothesis that the source and distribution of anthropogenic organic matter (OM) were significant factors affecting the spatial variation of the microbial community composition of the Yangtze River sediments. Bulk geochemical proxies and lignin phenols suggested a general decrease of terrestrial C3 plants or soil OM input from the middle to the lower reaches. Fecal sterols inferred higher sewage contamination levels in the middle reaches. Polycyclic aromatic hydrocarbons (PAHs) distribution indicated a dominant biomass and coal combustion signal in the middle reaches, whereas a mixed source including petroleum combustion in the lower reaches. Phylogenetic analysis revealed a large portion of Methanobacteria and Verrucomicrobia enriched in the middle reaches, whereas OM-degrading bacteria, including Flavobacteria, Acidobacteria, and Alphaproteobacteria were dominant in the lower reaches. Quantitative PCR analyses and multivariate analysis further demonstrated that sources and distribution of OM had combined effects in shaping alpha and beta-diversity of sediment microbial communities. Sewage discharge and incomplete OM combustion, respectively, were associated with Methylococcaceae, Chloroflexi, and Bacteroidetes groups. This study provides a foundation for further understanding of the river sediment microbial composition, considering the continued increase of anthropogenic influences. [ABSTRACT FROM AUTHOR]

Because nematodes are an important component of soil ecosystems, patterns of soil nematode community structure along geographic gradients have received considerable attention. However, little is known about the multidimensional spatial patterns of soil nematode communities under specific plants. Here, we examined soil nematode communities associated with roots of tallow tree (Triadica sebifera) along a latitudinal gradient spanning from 19.44° to 33.56° N in China. On Tianzhu mountain in central China (30.69° N), we also examined the distribution patterns of soil nematode communities associated with roots of T. sebifera along an altitudinal gradient spanning from 100 to 1000 m a.s.l. Through the integration of latitudinal and altitudinal gradients, our results show that latitudinal patterns of soil nematode community structure are mainly quadratic (low nematode abundance at mid-latitude), whereas altitudinal patterns are mainly linear (low nematode abundance at high altitude). Along with the differences in distribution pattern between latitudinal and altitudinal gradients, the relationship of factors to soil nematode community structure was also quite different in the two surveys. These results suggest that multidimensional and multifactorial studies are essential for revealing spatial distribution patterns, as well as the driving mechanisms, of soil nematode community structure. [ABSTRACT FROM AUTHOR]

• The distribution of age structure of P. yunnanensis showed an inverted J structure, which was in the transitional stage between growth type and stable type. • The aggregation degree of P. yunnanensis decreased gradually, the distribution pattern tended to be random, showed the density restriction effect. • The smaller the DBH difference, the stronger the positive correlation of survival among individuals in different stages. • Intra-specific competition leads to lodging or death, which encourage seedling growth in the new open space. The Sloping Land Conversion Program is also known as the 'Returning Farmland to Forest Program' intent to gradually recreate farmlands back to the original forested state. Providing cognition on the effects of the policy on the distribution of dominant species is important to better understand plant community structures, development dynamics, regeneration conditions, and possible underlying ecological mechanisms. The purport of this study is to inspect the population structure of Pinus yunnanensis in a 2500 m2 area of abandoned farmland where restituted to forest in 2004. The results showed that the population structure of P. yunnanensis settled on tree age formed an inverted J - distribution (20.1% seedlings, 34.2% young trees, 38.5% middle-aged trees, and 7.1% adult trees) since 2009, whereas seedlings, young trees, and middle-aged trees showed clustered distribution. Seedlings showed the highest aggregation degree (g(r) = 6.4), followed by young trees (g(r) = 2.3) and middle-aged trees (g(r) = 1.7), but a random distribution showed in adults throughout the research area. The spatial relationships among seedlings, young trees, middle-aged trees, and adults indicated that the aggregation consequences increased with the decreasing difference in the diameter at breast height. Furthermore, the correlation of canopy height and diameter at breast height decreased with the increasing competition among the individuals signified that seedlings and young trees growing in the same area might use fewer resources than needed. Generally, the study illustrated that intra-specific competition due to environmental resources is a rarely occurring event. [ABSTRACT FROM AUTHOR]

Microplastic pollution within the marine environment is of pressing concern globally. Accordingly, spatial monitoring of microplastic concentrations, composition and size distribution may help to identify sources and entry pathways, and hence allow initiating focused mitigation. Spatial distribution patterns of microplastics were investigated in two compartments of the southern North Sea by collecting sublittoral sediment and surface water samples from 24 stations. Large microplastics (500−5000 μm) were detected visually and identified using attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy. The remaining sample was digested enzymatically, concentrated onto filters and analyzed for small microplastics (11−500 μm) using Focal Plane Array (FPA) FTIR imaging. Microplastics were detected in all samples with concentrations ranging between 2.8 and 1188.8 particles kg−1 for sediments and 0.1–245.4 particles m−3 for surface waters. On average 98% of microplastics were <100 μm in sediments and 86% in surface waters. The most prevalent polymer types in both compartments were polypropylene, acrylates/polyurethane/varnish, and polyamide. However, polymer composition differed significantly between sediment and surface water samples as well as between the Frisian Islands and the English Channel sites. These results show that microplastics are not evenly distributed, in neither location nor size, which is illuminating regarding the development of monitoring protocols. Image 1 • All 46 analyzed sediment and surface water samples contained microplastics. • Microplastic concentrations were higher in sediment than surface water samples. • Polymer composition differed significantly between surface waters and sediments. • Microplastics <500 μm were more abundant and divers in polymer type than large ones. • Particles smaller 100 μm dominated clearly in both environmental compartments. Capsule: Microplastic concentrations and compositions differ significantly between environmental compartments. Geographic distribution patterns are revealed by a statistical approach. Microplastics <500 μm are more abundant and diverse than >500 μm ones, rendering the exclusive analysis of later ones insufficient for environmental risk assessment. [ABSTRACT FROM AUTHOR]

Abstract Many precious air-dried soil samples are currently stored by institutions across the world, and they have been proved useful in retrieving historical information of soil microbial ecology, such as the shifts of microbial populations and the effects of agricultural managements on soil microbial communities. However, most of those retrospective studies on microorganisms in archived soils were mainly conducted through PCR-DGGE or T-RFLP analysis, which was less sensitive to low-abundance species. In order to assess whether archived soils could reveal the spatial distribution of microbial communities at large spatial scale, especially the rare microbial taxa, a total of 117 serial time-historical samples from eight long-term field experimental stations of the Chinese Ecosystem Research Network were analyzed using high-throughput sequencing. The non-metric multidimensional scaling (NMDS) analyses showed that both the total bacterial communities and the rare bacterial subcommunities were distinctly clustered into different groups corresponding to each experimental station, and that analogous distribution patterns of bacterial communities existed between each two sampling years for both the total and the rare taxa, though the microbial community composition changed over time. The corresponding hierarchical clustering analyses demonstrated that soil bacterial communities for both the total and the rare taxa could be clustered into five groups for all samples and for the sub-samples of each sampling year, which corresponded to five eco-geographic regions in the Eco-Geographic Regional System of China. The results from this investigation highlighted the great value of serial time-archived soils in revealing the spatial distribution patterns of bacterial communities for both the total and the rare taxa at large spatial scale. Highlights • Consistent spatial patterns of bacteria revealed by serial time-archived soils. • The rare taxa mimicked the distribution patterns of the total taxa. • Soil bacterial distribution pattern in line with eco-geographic regions of China. [ABSTRACT FROM AUTHOR]

Abstract Three different empirical models based on Landsat, MERIS, and MODIS sensors were used to retrieve TSM concentrations and construct long-term TSM image datasets during the period from 2003 to 2011. These datasets were utilized to evaluate the suitability of Landsat, MERIS, and MODIS for identifying spatial distribution patterns of TSM concentration based on a self-organizing map (SOM) algorithm in the Pearl River Estuary (PRE). 12 spatial distribution patterns of TSM in the PRE were identified from long-term TSM data of each sensor based on a 4 × 3 SOM array. The expected frequency of occurrence of any given pattern and relative frequency of occurrence of each pattern were calculated and analyzed. The factors that influence the variability of TSM and the spatial distribution patterns of TSM were explained by the contribution of human activities, precipitation, and characteristics of satellite sensors. Our results showed that similar spatial distribution patterns of TSM were extracted from three different TSM image datasets. Each pattern presented a strip distribution from northeast to southwest, and the values of TSM decreased regularly from northwest to southeast. However, patterns identified from Landsat and MODIS TSM images presented some anomalous patterns, which were inconsistent with local circumstances and previous studies. High (low) level spatial distribution patterns of TSM in the SOM array were associated with a variety of high (low) values of TSM concentration in the PRE. Frequency analyses of each pattern demonstrated that notable differences of TSM concentration existed in the PRE from 2003 to 2011. These findings can assist us to better understand the dynamics of TSM concentration and the performance of different empirical models established by Landsat, MERIS, and MODIS for identifying spatial distribution patterns of TSM concentration using the SOM algorithm. Highlights • Long-term TSM of PRE was mapped using three models from Landsat, MERIS and MODIS. • 12 spatial patterns of TSM were identified using self-organizing map (SOM) algorithm. • The patterns were controlled by human activities, precipitation and satellite sensors. [ABSTRACT FROM AUTHOR]

Spatial analysis of forest tree distribution is a powerful tool to respond to basic ecological questions, and represent a useful support to strategies of genetic conservation and sustainable management practices of forest resources. Spatial analysis techniques combined with the use of Geographical Information Systems have been commonly applied to the study of stochastic processes in order to determine the existence of clusters to be related to microenviromental conditions and/or genetic factors. The present study focused on the distribution patterns of individuals of Mezilaurus itauba in a seasonal forest of the southern Amazon, with the aim of providing information about the spatial arrangement of these species at the juvenile and adult stages. Ripley’s K function with radius of 10, 20 and 30 m was used to describe spatial distribution patterns. The hypothesis of complete spatial randomness (CSR) of individuals was tested by constructing confidence envelopes for the Ripley’s K function through Monte Carlo simulations using a Poisson homogeneous process. The results obtained suggest a general random distribution of individuals, though a tendency to clustering at close distances was detected for individuals classified as adults (DBH > 50 cm). Contrastingly, a completely randomized spatial pattern was found for juveniles trees (DBH < 50 cm). Our results provide a useful baseline for the development of sustainable management plans and conservation of Mezilaurus itauba, as well as for other economically-exploited, native tree species in the southern Amazon forest.

ABSTRACT : Trees can modify the weed seed bank composition and distribution in the cropped area of an agroforestry system. This study aimed at analyzing the eucalyptus (Eucalyptus dunnii) effect on spatial distribution, functional traits abundance and weed seed bank botanic composition in an agroforestry system under no-tillage in Subtropical Brazil. The experiment was conducted in a randomized block design with five replications, and five positions between 4.5-year-old eucalyptus double rows [(4x3) x 20 m] as treatments. Soil sampling was performed at 0-20 cm and the method to quantify and identify seeds was the seedling emergence in trays, inside a greenhouse. Weed phytosociological indices (relative density, frequency and importance), functional traits abundance (life cycle, shade tolerance, reproduction, spread and seed form) and seed densities (m-2) of families and species were evaluated; 17 weed families and 49 species were found. The indices that contributed to the relative importance of families and species differed among the positions between rows. Eucalyptus grown as an intercrop changed the composition and size of the weed seed bank, in a different way for functional traits, families and species depeding on the distance from trees.

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Spatial distribution patterns of microzooplankton (0.055–0.3 mm) biomass and abundance were studied in relation to the hydrographic situation and the local flow field in the waters off Ampère and Senghor, two shallow seamounts in the subtropical and tropical NE Atlantic, in comparison with unaffected open ocean reference sites. Ampère was sampled during November/December 2010 and Senghor during December 2011 and February 2013. The study includes taxonomic composition, abundance of meroplanktonic larvae and an estimation of the respiratory carbon demand. Biomass (dry weight) standing stocks of microzooplankton in the upper 100 m ranged between 30–120 mg m−2 over Ampère and 140–260 mg m−2 over Senghor Seamount, corresponding to 33 and 24% of the total zooplankton (0.055–20 mm). Highest total abundance was always found in the upper 50 m with numbers of 1070–5060 Ind m−3 at Ampère and 5050–20,000 Ind m−3 at Senghor with microzooplankton contributing 70–95%. Zooplankton accumulated mainly at the thermocline coincident with the deep fluorescence maximum and was ascertained by food supply rather than by oxygen limitation. The microzooplankton contribution to the total respiratory carbon demand was ~50% in the subtropical waters off Ampère and ~30% at Senghor, reflecting the important role of microzooplankton in the waters of the NE Atlantic subtropical gyre. Clear evidence of local seamount effects resulting in enhanced microzooplankton biomass compared with the unaffected reference sites were not detected. However, we confirmed Senghor as a hotspot for meroplanktonic larvae, suggesting a retention potential that results in significantly enhanced larval abundance in the seamount waters as compared with the open ocean. [ABSTRACT FROM PUBLISHER]

Post-fire field measurements of sediment and run off yield were undertaken in natural rainfall event-basis during five rainy months in Korea on a total of 15 small plots: four replica burned unseeded plots, six replica burned seeded plots, and five replica unburned plots. The main aim was to evaluate the effects of vegetation recovery and spatial distribution patterns on sediment and runoff response between and within the treatment replica erosion plots. Six-years after the wildfire, total sediment and runoff yield in the burned unseeded plots with 20%-30% vegetation cover was still 120.8 and 20.6 times higher than in the unburned treatment plots with 100% ground cover, 8.3 and 6.7 times higher than in the burned seeded plots with 70%-80% vegetation cover, while only 1.6 and 2.0 times higher than in the burned seeded plots with 50%-60% vegetation cover, respectively. The differences in sediment and runoff yield between the treatment plots was proportional to total vegetation cover, distance of bare soil to vegetation cover, magnitude of rainfall characteristics and changes in soil properties, but not slope gradient. Three out of the six within-treatment pairs of two replica plots showed large differences in sediment and runoff yield of up to 6.0 and 4.2 times and mean CV of up to 99.1% and 62.2%, respectively. This was due to differences in the spatial distribution patterns of surface cover features, including aggregation of vegetation and litter covers, the distance of bare soil exposed to vegetation cover closer to the plot sediment collector and micro topographic mounds and sinks between pairs of replica plots. Small differences in sediment and runoff of only 0.9-1.4 folds and mean CV of 8.6%-25% were observed where the within-treatment pairs of replica plots had similar slope, total surface cover components and comparable spatial distribution pattern of vegetation and bare soil exposed surface covers. The results indicated that post-fire hillslopes undergoing effective vegetation recovery have the potential to reduce sediment and runoff production nearer to unburned levels within 6-years after burning while wildfire impacts could last more than 6-years on burned unseeded ridge slopes undergoing slow vegetation recovery. [ABSTRACT FROM AUTHOR]

Abstract The tree species composition of seasonally dry tropical forests (SDTF) in north‐eastern and central Brazil is analyzed to address the following hypotheses: (1) variations in species composition are related to both environment (climate and substrate) and spatial proximity; (2) SDTF floristic units may be recognized based on peculiar composition and environment; and (3) the Arboreal Caatinga, a deciduous forest occurring along the hinterland borders of the Caatinga Domain, is one of these units and its flora is more strongly related to the caatinga vegetation than to outlying forests. The study region is framed by the Brazilian coastline, 50th meridian west and 21st parallel south, including the Caatinga Domain and extensions into the Atlantic Forest and Cerrado Domains. Multivariate and geostatistic analyses were performed on a database containing 16,226 occurrence records of 1332 tree species in 187 georeferenced SDTF areas and respective environmental variables. Tree species composition varied significantly with both environmental variables and spatial proximity. Eight SDTF floristic units were recognized in the region, including the Arboreal Caatinga. In terms of species composition, its tree flora showed a stronger link with that of the Cerrado Dry Forest Enclaves. On the other hand, in terms of species frequency across sample areas, the links were stronger with two other units: Rock Outcrops Caatinga and Agreste and Brejo Dry Forests. There is a role for niche‐based control of tree species composition across the SDTFs of the region determined primarily by the availability of ground water across time and secondarily by the amount of soil mineral nutrients. Spatial proximity also contributes significantly to the floristic cohesion of SDTF units suggesting a highly dispersal‐limited tree flora. These units should be given the status of eco‐regions to help driving the conservation policy regarding the protection of their biodiversity.

The algorithm to generate spatial distribution patterns was developed and presented in this study. Three typical spatial distribution patterns, i.e., Poisson distribution, binomial distribution, and negative binomial distribution were included in the algorithm. The Java program was also provided. The algorithm can be used to generate initial distribution in cell automata modeling.

New energy vehicles (NEVs) have been recognized as a sustainable eco-innovation to address China's energy and environment problems. As a strategically emerging industry, China's NEV manufacturing industry has been prioritized by governments and manufacturers, significantly impacting its spatial distribution pattern and stimulating the goals of carbon peaking and carbon neutralization. China, the largest NEV producer and consumer and with distinctive regional diversity, has experienced a new round of capacity expansion. Therefore, the literature on the spatial distribution patterns and influencing factors of NEV industry in provincial level is vital for the transformation of manufacturing industry and transportation sector, while to date, the related studies is few. In this paper, considering the number and location of key enterprises/production bases, the spatial distribution and influencing factors of China's NEV industry were discussed by an empirical study. The results are gained from a spatial perspective. Firstly, in general, China's NEV industry presents a "T" spatial distribution pattern. Secondly, a point-axle spatial exploration pattern is proposed, which includes "four points and one axle" namely Bohai rim, Yangtze River Delta (YRD), Pearl River Delta (PRD), Hubei-Chongqing clusters and Eastern Coastal NEV industrial belt. Thirdly, different types of NEV enterprises show various location preferences and spatial distribution characteristics. Fourthly, the influencing factors on China's NEV spatial distribution are concluded from five aspects of supporting policy, infrastructure condition, economic drivers, technical capacity, and industrial foundation, and the degree of factors is different considering varying enterprise classification and industrial development stage. The findings of this paper provide a reference for rational layout in China's NEV industry, and are expected to stimulate the sustainable development of NEVs. [ABSTRACT FROM AUTHOR]

Grass coverage and its spatial distribution patterns have crucial influences on erosion. The laboratory scouring experiments were conducted to research the influence of grass cover on runoff, erosion rates, and overland flow hydraulic characteristics in the plots with differing grass coverage rates (30, 50, 70, and 90 %), grass distribution patterns (where US, MS, and DS stand for the grass laid on up-slope, middle-slope and down-slope, respectively) and with a bare soil plot (CK) at a slope gradient of 20. The results illustrate that the grassplots had a 2.06-10.94 % runoff reduction and 28.57-75.4 % sediment decreases, respectively, as compared with CK plot. There was no significant difference in the runoff rate among the three grass distribution patterns for the same grass coverage, while DS had the lowest sediment yield rate and greatest sediment yield reduction in comparison with US and MS. The sediment yield rates were found to have a significantly negative exponential relationship with the grass coverage ( p < 0.01), while the sediment concentration had a significantly negative linear relationship with the grass coverage ( p < 0.01). The overland flow velocity ( V) increased with increasing inflow discharges and deceased with increasing grass cover, and it was negatively correlated with the grass coverage following a linear trend ( p < 0.01). The mean Froude number ( Fr) holds to a similar variation law with the changes in the V. There was no significant relationship found to exist between the grass coverage and Reynolds number ( Re). The average Darcy-Weisbach resistance coefficient ( f) of the whole slope for grass plots was 2.2-25.6 times of that for CK plot, and f was found to be an exponent correlated with the coverage rate ( p < 0.01). In addition, f was negatively correlated with the erosion rate following a power function ( p < 0.01); however V, Fr, and Re were positively correlated with the erosion rate ( p < 0.01). The sediment yield rate itself was a function of the runoff rate for each treatment, and their relationships could be well described by the linear equation ( p < 0.01). These results indicate that both grass coverage rates and distribution patterns have significant effects on hydrological characteristics of overland flow. [ABSTRACT FROM AUTHOR]

Spatial distribution patterns and their relations with environmental factors at different scales were identified in ca. 100-ha grassland under cattle and sheep grazing, in Eldorado do Sul, RS, Brazil (30º05'S, 51º40'W). The field survey used 138 0.5 x 0.5 m quadrats located systematically on transects along relief gradients. The quadrats were arranged in groups of 3 contiguous quadrats, which were pooled for the analysis, thus forming 46 quadrats 1.5 x 0.5 m, in this way defining two observation scales. Vegetation description involved recording the presence and the visual estimation of cover-abundance of species in each quadrat. A total of 148 species belonging to 30 families was detected. The environmental conditions at each site were described by 30 variables related to soil chemical and physical properties, slope, exposure and relief position. Data analysis used cluster analysis, evaluation of group partition sharpness, ordination, significance of ordination axes, evaluation of environmental congruence and randomization testing. The results of the analysis with 46 quadrats supported those found with 138 quadrats. The vegetation patterns in the study area are associated to relief position and other related factors such as soil moisture. Two clearly defined grassland community types were detected, one occurring on the slopes and another on the wet lowlands.

• The reliability of the stress wave non-destructive testing technique in the trunk defects diagnosis of Populus euphratica riparian forest in extreme arid desert conditions was verified. • The trunk internal decay of P. euphratica was negatively correlated with tree vitality. • There was a significant positive correlation between tree trunk decay and groundwater depth. • The trunk decay occurrence in the lower reaches was much higher than that in the middle reaches of the Tarim River. Trunk internal decay is a common phenomenon in forest ecosystems, causing the loss of forest resources. Euphrates poplar (Populus euphratica Oliv.) is the only constructive tree species of the desert riparian forests along the Tarim River in northwestern China. The ecosystem stability of these forests has been damaged due to widespread internal decay or hollow rot in many tree trunks. However, forest resource conservation is difficult due to the unclear spatial patterns of P. euphratica trunk decay under different water conditions and tree morphology in the middle (MTR) and lower reaches (LTR) of the Tarim River. We conducted a field experiment and lab analysis to assess the reliability of the ARBOTOM® 2D stress wave Non-Destructive Testing (NDT) technique on P. euphratica populations. We explored the quantitative characterization method and the spatial distribution patterns of P. euphratica trunk internal decay in the MTR and LTR. Our study found that (1) the accuracy of the stress wave NDT technique in detecting trunk decay of P. euphratica in the arid desert area was more than 80%; The severity of internal trunk decays can be quantitatively characterized by the combination of the Matlab Image Processing Toolbox, (2) the trunk decay proportion of P. euphratica showed an increasing trend with the tree height in the MTR. The LTR first increased, then decreased. The degree of decay was highest when the tree height was 6–7 m. The trunk decay proportion of individual trees positively correlated with the diameter at breast height and crown loss (p < 0.001) and negatively correlated with the crown diameter (p < 0.001). The higher the decay occurrence, the worse the individual size was, and vice versa, and (3) the decay proportion of the P. euphratica showed an overall increasing trend with an increase in groundwater depth. The trunk decay was significantly higher in the LTR compared to the MTR at the same distance of 300–1050 m from the river channel. Our findings suggested that the trunk decay in P. euphratica had a higher difference among different tree morphology, and the occurrence of decay in the LTR was much higher than in the MTR. The water stress at the site is one of the leading factors in internal defects in the riparian forests along the Tarim River. The results provide a theoretical basis and scientific support for desert riparian forest ecosystems' conservation and sustainable management. [ABSTRACT FROM AUTHOR]

Qinglong County in Guizhou, China is a typical karst canyon area. Using quadrat methods and a land use transfer matrix we studied the carbon storage spatial distribution pattern and evolution process over three independent periods (1988, 1999 and 2009) in this area. Based on the results we estimated the carbon pool capacity of the entire karst canyon area in Guizhou and contribution ratios. Carbon storage and average carbon density of the karst area in Qinglong decreased at first, and then increased over the sampling period. The actual carbon storage of the karst canyon area in Guizhou was estimated to be 42.55 Tg. The average carbon intensity of the karst canyon area in Guizhou is far higher than that of national terrestrial ecosystems, especially in vegetation areas. Through cross comparison, we found that karst canyon areas have great carbon sequestration potential and we suggest that it is necessary to control and prevent rocky desertification in karst areas in China. [ABSTRACT FROM AUTHOR]

• Soil nematode communities in subtropical evergreen broad-leaved forests differed from those in other climate zones. • Abundances and diversity showed hump-shaped patterns among altitudinal climate zones. • Relative abundances declined for fungivores and increased for omnivores-predators among climate zones. • Changes in the relative abundances of fungivores and omnivores-predators shifted the trophic structure among climate zones. • The distribution of soil nematodes was affected by vegetation type and soil properties. Revealing the distribution patterns of soil nematode communities among climate zones helps uncover the spatial distribution patterns of belowground biodiversity. The aims of this study were to reveal the spatial distribution patterns of the taxonomic composition, diversity and trophic structure of soil nematode communities among continuous climate zones. Investigations were conducted for five altitudinal vegetation types, i.e., subtropical evergreen broad-leaved forest (SEB), subtropical evergreen and deciduous broad-leaved mixed forest (SEDB), warm temperate deciduous broad-leaved forest (WTDB), mid-temperate coniferous and broad-leaved mixed forest (MTC) and cold temperate coniferous forest (CTC), on the eastern slope of Gongga Mountain from 2014 to 2017. The taxonomic compositions of the soil nematode communities in the SEDB, WTDB, MTC and CTC were similar but differed markedly from that in the SED, with patterns varying among sampling years. Abundances and diversity showed unimodal distribution patterns, with maximum values occurring in the WTDB. The abundances of the four trophic groups varied significantly among the vegetation types. Relative abundances stabilized for bacterivores and plant parasites but declined for fungivores and increased for omnivores-predators from the SEB to the CTC. The ratio of fungivores to bacterivores in the SEB was significantly higher than those in the other vegetation types, implying that the trophic structure and material cycling channels differed among forest types. The spatial distribution of the soil nematode communities was mainly influenced by pH, total K, total P and soil temperature. These findings suggested that the taxonomic composition, abundance, diversity and trophic structure of soil nematode communities vary among climate zones, but the changes in the soil nematode communities among climate zones did not keep pace with those in aboveground plant communities. [ABSTRACT FROM AUTHOR]

Coastal wetlands in north Jiangsu Province are the most typical mudflat in China, and they lie between estuaries of the Yangtze River and the abandoned Yellow River. This paper primarily aims to examine the evolution features and spatial distribution patterns between 1980 and 2008 in this region by using remote sensing with Landsat TM images and ALOS images in 1980 and 2008, respectively. Results indicate that the total coastal wetland area has decreased by 1273.11 km, that is, by 45.47 km every year, whereas erosion/sedimentation area expanded to approximately 965.14 km with a loss of only about 307.97 km. The study area is subdivided into six coastal sections from north to south and three units from the inland to the sea. The three units, namely, overlap unit (boundary fixed coastal wetland area between 1980 and 2008), changed unit (boundary changed coastal wetland area between 1980 and 2008), and mudflat unit. The area change of pattern change, wetland loss, and habitat evolution account for 38.39 %, 14.97 %, and 20.51 % of the total studied area, respectively. This finding suggested that most pattern change and wetland loss occurred in the overlap unit, whereas habitat evolution mainly occurred in the changed unit. The natural wetlands area was reduced by 354.1 km, whereas the constructed wetlands and non-wetlands expanded by 1061.45 and 253.09 km, respectively. Vegetation communities in the studied area also have distinct regional succession features and spatial patterns. The new integrated model that is based on spatial segmentation and transfer matrix and applied in this paper is proven effective in characterizing the spatial-temporal features of wetlands. [ABSTRACT FROM AUTHOR]

• Dryland soil organic carbon (SOC) storage to a depth of 40 cm was 1922.38 Tg. • SOC density and storage increased from southwest to northeast at different depths. • SOC density variation was mainly controlled by mean annual temperature and bulk density. • The total effect of soil management on SOC density decreased with increasing depth. The knowledge of the spatial distribution of soil organic carbon (SOC) and of its influencing factors is crucial for understanding the global carbon cycle. Although the influence of climate, soil properties, and soil management on the SOC content has been extensively explored, their relative importance remains unclear, especially under dryland farming. Herein, we investigated the SOC density (SOCD) at different depths (0–10, 10–20, 20–30, and 30–40 cm) across an area of 37.79 × 104 km2 (420 sites) located in the dryland farming regions of Northeast and North China. The total SOC storage (SOCS) was estimated to be 1922.38 Tg, with a mean density of 5.78 kg C m−2 for the entire area. The three soil groups with the largest SOCS were Fluvo-aquic, Black, and Chernozem soils, accounting for 63.34% of the total SOCS in the study area. Overall, both the SOCD and SOCS increased from southwest to northeast at all investigated depths. A structural equation model was used to distinguish direct from indirect effects of different factors on SOCD. Soil properties (e.g., bulk density and pH) and natural conditions (e.g., mean annual temperature and mean annual precipitation) were found to be the main factors controlling the SOCD variation at depths of 10–20, 20–30, and 30–40 cm. However, the total (direct and indirect) effect of soil management on SOCD at a 0–10 cm depth was greater than that of natural conditions, and smaller than that of soil properties. With increasing soil depth, the total effect of natural conditions on SOCD changed from –0.33 to –0.58, whereas the indirect effect of soil management decreased from 0.47 to 0. These results indicate that compared with environmental factors, soil management practices such as tillage and fertilization had a greater influence on SOCD in the surface soil of dryland. Our study provides a valuable reference for future research on the long-term evolution of SOC in dryland farming regions. [ABSTRACT FROM AUTHOR]

Abstract: Afforestation of native-tree species is often recommended for ecological restoration, but the understanding of ecological processes of restored vegetation is limited. We investigated the population structure and spatial distribution patterns of restored forest in mine spoil of Pingshuo opencast mine, Shanxi Province, China. After 17 years’ development, three planted species (ROPS, ULPU and AIAL) showed significant aggregation although they were regularly distributed at plantation and characterized with great variability in abundance (from 570 to 1817) although they had equal density at plantation. ROPS became the dominant species, especially in the naturally regenerated medium individuals with 3

To identify the sapling species that can be planted in spruce-fir forest in the Changbai Mountains, China, we analyzed the associations among saplings and between saplings and adult trees of 4 tree species (spruce [Picea koraiensis Nakai], fir [Abies nephrolepis (Trautv.) Maxim.], Korean pine [Pinus koraiensis Sieb. et Zucc.], and lime [Tilia amurensis Rupr.]), and the spatial distribution of saplings under the adult trees. We observed positive associations between the saplings and adult trees of spruce, fir, Korean pine, and lime. In addition, the numbers of saplings of spruce, fir, Korean pine, and lime with distance from adult trees exhibited a positively skewed distribution. We conclude that saplings of any one or several of these 4 species can be planted in the mixed forests and the optimum distance between saplings and adults trees of the coniferous species is 2-3 m, whereas the corresponding optimal distance from the broadleaved lime is 4-5 m. Our results provide new insights into the development of reforestation techniques in spruce-fir forests in the Changbai Mountains. [ABSTRACT FROM AUTHOR]

The article presents information on a study which examined and contrasted the spatial pattern of herds in a population of capybara, Hydrochoerus hydrochaeris, in the eastern savannas of Colombia. Background on the distribution of capybara, a social rodent from the lowlands of South America, is presented. Herd spatial location was utilized for the construction of point pattern plots for each of the seasons investigated and point pattern analysis (PPA) methodology was also used to determine whether the observed point pattern plot can be considered to have a regular, random or aggregated pattern. It discusses the findings of the study.

Recently, populations of Castanopsis cuspidata have often expanded into secondary forests in western Japan. To determine the establishment processes of this species, we analyzed its spatial distribution in a secondary forest dominated by Quercus variabilis and Quercus serrata that is located adjacent to a stand dominated by C. cuspidata. Saplings, defined as ≥30 cm stem length (SL) and <5 cm diameter at breast height (DBH), were abundant and their size distribution was inversely J-shaped, indicating continuous recruitment. Although seedlings (SL < 30 cm) and small saplings (30 ≤ SL < 50 cm) of C. cuspidata were aggregated near flowering trees of this species, some were found ≥40 m from the nearest adults, suggesting that there is animal-aided dispersal of acorns. The distribution of larger-sized individuals (≥100 cm SL) of C. cuspidata was unrelated to distance from the nearest flowering C. cuspidata or dominant Quercus species (≥5 cm DBH), but was associated with dead Pinus densiflora trees, which were abundant at the site. Thus, the establishment of C. cuspidata in this forest is controlled mainly by two factors, viz. patterns of acorn dispersal by animals, and forest disturbance regime (i.e., deaths of pine trees). [ABSTRACT FROM AUTHOR]

The article presents a study that determines the status of subtidal accumulations of rocky benthic in three marine protected areas (MPAs) of Canary Islands such as La Graciosa, Mar de Las Calmas, and La Palma. Populations of Diadema aff. antillarum (sea urchins) and non-crustose macroalgal cover were surveyed, which are then used as indicators of the conservation status in the three areas, as well as in an highly-fished area (HFA). A comparison between the characteristics of MPAs and the HFA is also presented. It also discusses the significance of the differences to the grazing activity of the sea urchin being the key herbivore of the whole area.

The main objective of this study was to fit and recognize spatial distribution patterns of grassland insects using various neural networks, and to analyze the feasibility of neural networks for detecting spatial distribution patterns of grassland insects. BP neural network, Learning vector quantization (LVQ) neural network, linear neural network and Fisher’s linear discriminant analysis were used to fit and recognize spatial distribution patterns at different ecological scales. Various comparisons and analysis were conducted. The results showed that BP, LVQ and linear neural networks were better algorithms for recognizing spatial distribution patterns of grassland insects. BP neural network was the best algorithm to fit spatial distribution patterns. BP network may be used to recognize the spatial details of distribution patterns, and the recognition performance of BP network became better as the increase of the number of hidden layers and neurons. Performance of linear neural network for pattern recognition was similar to linear discrimination method. Linear neural network would yield better performance in finding the general trends of distribution patterns. Recognition performance of LVQ network was just between BP network and linear network. It was found that recognition performance of neural networks depended upon not only the ecological scale but also the criterion for classification. Under the uniform criterion, recognition efficiency of linear methods tended to be weak as ecological scale became to be coarser. A joint use of neural networks was suggested in order to achieve both overall and detailed understanding on spatial distribution patterns. [ABSTRACT FROM AUTHOR]

Abstract: The concentrations of platinum group elements (PGE; platinum, palladium, rhodium) and 17 other elements in mosses growing at 32 sampling sites along 12 roads in Austria were analysed. The study included passive monitoring of naturally growing mosses with an experimental design using mosses samples exposed in a tunnel experiment. PGEs (Pt, Pd, Rh) were analysed by ICP-MS (ELAN DRC II, Perkin Elmer SCIEX) according to EN ISO 17294-2 Tl.29. Mean concentrations of PGEs in five moss species were: Pt 7.07±9.97, Pd 2.8±5.2 und Rh 0.6±0.8ngg−1 dry weight. This is comparable to data derived from measurements of gasoline autocatalyst emissions or airborne particles (<10μm). Compared to soils and road dust along highways, concentrations in mosses were lower by a factor of ten, compared to grasses they were comparable or somewhat higher. The ratios between the various PGEs were calculated as follows (mean values): Pt/Pd 7.9±10.2, Pt/Rh 12.6±8.3 and Pd/Rh 3.7±2.2. The number of light duty vehicles (<3.5t) and the distance from the road were the main influential factors for PGE concentrations. Especially strong correlations could be found between Pt and Sb, Cu, Zn, and Cd (in decreasing order), which are all elements derived mainly from road traffic emissions. Cluster analysis (Partioning Around Medoids Method) separated elements derived mainly from soil dust (Ca, Al). An analysis of spatial deposition patterns of PGEs showed a reciprocal decrease of concentrations with increasing distance from the road, reaching background values at distances between 10 and 200m, sometimes even more, but outside the spatial range of our investigation. [Copyright &y& Elsevier]

This article presents a computer program, Micro3D, designed for 3-D reconstruction, visualization, and analysis of coordinate-data (points and lines) recorded from serial sections. The software has primarily been used for studying shapes and dimension of brain regions (contour line data) and distributions of cellular elements such as neuronal cell bodies or axonal terminal fields labeled with tract-tracing techniques (point data). The tissue elements recorded could equally well be labeled with use of other techniques, the only requirement being that the data collected are saved as x,y,z coordinates. Data are typically imported from image-combining computerized microscopy systems or image analysis systems, such as Neurolucida (MicroBrightField, Colchester, VT) or analySIS (Soft Imaging System, GmbH, Münster, Germany). System requirements are a PC running LINUX. Reconstructions in Micro3D may be rotated and zoomed in real-time, and submitted to perspective viewing and stereoimaging. Surfaces are re-synthesized on the basis of stacks of contour lines. Clipping is used for defining section-independent subdivisions of the reconstruction. Flattening of curved sheets of points layers (e.g., neurons in a layer) facilitates inspection of complicated distribution patterns. Micro3D computes color-coded density maps. Opportunities for translation of data from different reconstructions into common coordinate systems are also provided. This article demonstrates the use of Micro3D for visualization of complex neuronal distribution patterns in somatosensory and auditory systems. The software is available for download on conditions posted at the NeSys home pages ( http://www.nesys.uio.no/ ) and at The Rodent Brain Workbench ( http://www.rbwb.org/ ). [ABSTRACT FROM AUTHOR]

The spatial distributions of canopy and subcanopy species (≥50 cm stem length) were investigated within a plot extending from the top of a ridge to the valley bottom in a cool-temperate old-growth mixed forest, dominated by Cryptomeria japonica and Fagus crenata , in the snowy region of Japan. Based on the longitudinal profile of the slope, the study slope was divided into the relatively gentle upper slope position (US), the steep lower slope position (LS), the flat valley bottom (VB) and the boundary zone between the upper and lower slopes (BS). Spatial dispersal and the association patterns of species were analyzed in upperstory (≥10 cm d.b.h) and understory (<10 cm d.b.h) layers. Dominant species in the upperstory layer abruptly changed from Cryptomeria to Fagus at the BS site. In contrast, the understory trees of many species, including shade-intolerant and evergreen species, were independent of the location of conspecific upperstory trees or canopy gaps and extended their distributions on and around the BS site. Significant, diverse canopy and subcanopy species occurred at this site in both upperstory and understory layers. On the BS site, which is the lower margin of Cryptomeria -dominated vegetation, there were many medium-sized C. japonica that were killed by uprooting or breaking of the stems as a result of heavy snow pressure. It is suggested that the snow pressure gradient along a slope has a strong influence on community structure and the maintenance of diverse canopy and subcanopy species in this snowy mixed forest. [ABSTRACT FROM AUTHOR]

[Display omitted] • One new collaborative verification strategy was used for verifying soil map. • The hyperspectral and time series multispectral images were used for soil mapping. • The semivariogram and percentage errors were used for collaborative verification. • The time series multispectral images were important for agricultural soil mapping. High-precision digital soil organic carbon (SOC) stocks mapping is very important for agricultural production management and global carbon cycle. The spatial heterogeneity of farmland SOC is not only influence by the environmental factors of soil formation but also the management practices of tillage, fertilization, and irrigation. However, the traditional modeling covariates of digital soil mapping, such as terrain factors, land use types and climate factors have weak spatial variations in low-relief agricultural areas, and they cannot reflect the large spatial variation of SOC. Thus the time-series multispectral remote sensing images will be used for mapping soil properties in low relief regions in this study, meanwhile a new collaborative verification strategy was put forward to evaluate the spatial distribution characteristics of soil maps. The current study was performed in a nearly flat agricultural region southeast of Iowa (with an area of approximately 385.45 ha), where 195 surface soil samples (0–15 cm) were collected. A hyperspectral image (Headwall-Hyperspec, 380–1700 nm) and the time-series multispectral remote sensing images of Sentinel 2 and Landsat 8 were used to construct the prediction models of SOC stock and its relevant soil properties of SOC and soil bulk density (SBD) through partial least square regression (PLSR) and extreme learning machine (ELM) models. The collected soil samples and evaluation indexes of root mean square error (RMSE), R2, and ratio of performance to interquartile range (RPIQ) were used to evaluate the model performance. Results are as follows: (1) hyperspectral images were successfully used to predict the SOC stock, SOC, and SBD through PLSR and ELM, while ELM (RPIQ = 2.03, 1.97, 1.64) outperformed PLSR (RPIQ = 1.83, 1.97, 1.53); (2) the time-series multispectral remote sensing images of Sentinel 2 and Landsat 8 can reflect the spatial distribution characteristics of the SOC stock, SOC and SBD by PLSR and ELM, but the combination of Sentinel 2 images and ELM obtained the best prediction results (RPIQ = 1.45, 1.25, 1.26); and (3) the differences of the soil maps predicted by the hyperspectral image and time-series multispectral remote sensing images were small, and the largest percentage errors nearly appeared on the edges of the farmland patches owing to mixed pixels. This study further confirmed the good prediction abilities of the time-series multispectral remote sensing images in low relief farmland regions. Lastly, this mapping strategy can provide additional valuable information for agricultural management and carbon cycle. [ABSTRACT FROM AUTHOR]