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Purpose: Using river sediments as a soil amendment has hundreds to a thousand years of history in the river plain network region of southern China. This study aimed to investigate the pollution conditions of heavy metals in cultivated soils consistently amended with river sediments for a long term. Materials and methods: Soil samples were collected in agricultural fields which were amended with river sediments for a long term. Soil heavy metals (Cr, Ni, Cu, Zn, Pb, Hg, As, and Cd) were determined and then assessed using Nemerow's comprehensive pollution (NCP) and potential ecological risk (PER) indices. A combination of correlation, principal components, and hierarchical cluster analysis was employed to analyze the source of soil heavy metals. Results and discussion: Soil Cu, Zn, Ni, Cd, and Cr exceeded the Chinese criterion with excessive Ni levels (719.0 %) in paddy soils and Cu levels (367.8 %) in dryland soils. Soil Cd and Hg had moderate levels of ecological risk. The contamination of soils with heavy metals was graded as heavy by the NCP index or high (paddy soils) and moderate (dryland soils) by the PER index. That is, the soils have accumulated serious levels of heavy metals according to the Chinese assessment criterion. The source of heavy metals in the studied soils is shown to be mainly attributed to anthropogenic activities and environmental effects (e.g., river sediment application, atmospheric deposition). Conclusions: Therefore, as a traditional practice for soil amendment, the use of localized river sediments in this region should cease until the quality of the sediments has been assessed. [ABSTRACT FROM AUTHOR]

Purpose: Biochar can be used to amend acidic soils, and the effectiveness of this amendment may be varied under different ventilation conditions. This study aimed to clarify the effect the incubation method (either ventilation or sealed conditions) had on the capacity of biochar to amend acidity of a typically acidic agricultural soil in hilly red soil region of southern China. Materials and methods: Biochars pyrolyzed from the bark (PB) and the trunk (PT) of Pinus massoniana, a widely distributed tree species in the region, were prepared. Sealed treatments consisted of 100 g soil + 2 g PB (PBS), 100 g soil + 2 g PT (PTS), and 100 g soil only (CKS). Ventilated treatments were conducted correspondingly (PBV, PTV, and CKV). During the 68-day incubation, soil pH was measured periodically. Results and discussion: Both biochars, PB and PT, amended the soil acidity significantly, e.g., increased soil pH and exchangeable cations, and decreased soil exchangeable acidity and exchangeable aluminum. After incubation, soil pH in PBS and PTS increased by 0.30 and 0.16 units, respectively, while soil pH in PBV and PTV increased by 0.25 and 0.11 units, respectively. Moreover, more positive effects on soil exchangeable acidity and nitrate nitrogen were also observed in sealed rather than in ventilated treatments. Conclusions: The results suggested that waste of P. massoniana can be pyrolyzed for soil acidity amendment in this region. While the effectiveness of biochar on acidity amendment of the soil can be influenced by the aeration conditions, other local environmental conditions may be involved and should also be considered when assessing soil amendments. [ABSTRACT FROM AUTHOR]

Integrated coastal management (ICM) has been introduced and promoted globally for nearly half a century. About 12% of China’s coastline has now come under the ICM governance framework to address the environmental and management challenges. To test the effectiveness of ICM in China, three coastal cities that adopted the ICM framework were selected as case studies. The ICM indicators in terms of governance, environment and socioeconomic aspects were designed for quantitatively evaluating the ICM performance over a 9-year period from 2004 to 2012.The results showed that ICM performance based on governance, coastal environment and socioeconomic aspects in the three improved, indicating that the ICM approach can be effective in promoting the overall sustainability of China’s coastal cities. [ABSTRACT FROM AUTHOR]

Sediments are considered to be important sinks of microplastics, but the enrichment process of microplastics by blue carbon ecosystems is poorly studied. This study analyzed the spatial distribution and temporal changes, assessed the polymer types and morphological characteristics of microplastics in sediments of five ecosystems, i.e. forests, paddy fields, mangroves, saltmarshes and bare beaches on Ximen Island, Yueqing Bay, China. The trapping effect of blue carbon (mangrove and saltmarsh) sediments on microplastic was further explored. Temporal trends in microplastic abundance showed a significant increase over the last 20 years, with the enrichment of microplastics in mangrove and saltmarsh sediments being 1.7 times as high as that in bare beach, exhibiting blue carbon vegetations have strong enrichment effect on microplastics. The dominant color, shape, size, and polymer type of microplastics in sediments were transparent, fibers and fragments, <1 mm, and polyethylene, respectively. Significant differences in the abundance and characteristics of microplastics between intertidal sediments and terrestrial soils reveal that runoff input is the main source of microplastics. This study provided the evidence of blue carbon habitats as traps of microplastics. • The main source of microplastics in the study area is the input of runoff. • The microplastic abundance increases significantly over the last 20 years. • Microplastics enrichment in blue carbon sediment is 1.7 times as high as that in bare beach. • The types of microplastics with the largest content were PE (27.2 %) and PVC (22.8 %). • Dominance of fibers and fragments, as well as microplastic smaller than 1 mm [ABSTRACT FROM AUTHOR]

This paper evaluates the quality characteristics of existing versions of 3-arc-second SRTM and 1-arc-second GDEM over Anji County, Zhejiang, China using reference elevations from a high-quality 1:10 k topographic map. Results show that SRTM has higher accuracy (RMSE =12.44 m) than GDEM (RMSE=14.20 m for Version 1, 12.76 m for Version 2); however, unsatisfactory void filling and an overall 1/2 pixel shift exits in SRTM version 4.1. Although spurious elevations over omitted water bodies still persist, GDEM Version 2 demonstrated significant improvement over Version 1. Accuracies of both SRTM and GDEM decrease on steeper slopes. Aspect also influences both the magnitude and the sign of errors. DEM accuracy in non-forested areas is considerably higher than that in forested areas. SRTM version 4.1 and GDEM version 2 possessed actual spatial resolutions of 90 m, despite both of them failed to match their nominal accuracies. SRTM Version 4.1 could be the first choice, while ASTER GDEM Version 2 would be a good alternative for areas where extensive voids exist in SRTM. [ABSTRACT FROM PUBLISHER]

Thyroid cancer (TC) incidence has significantly increased worldwide in recent decades, with large differences between urban and rural areas. However, studies on Chinese TC incidence are limited. Research on the relationship between TC incidence and industry activities is also rare. In this work, data from 31 cancer registry cities in China between 2005 and 2009 were used to reveal the trend of TC incidence, compare the incidence among different cities, and analyze the relationship of TC incidence with socioeconomic factors. During the five-year period, TC incidence in China increased by 49.5 % from 3.21/100,000 to 4.80/100,000, with a female-male ratio of 3 and an urban-rural ratio of 2.5. The increase of TC incidence in more developed cities was significant, but it was not in less developed cities. People living in cities with higher secondary industry output had a higher risk of developing TC. The government and scientific community should pay sufficient attention to the rapidly increasing incidence of TC and to industry activities. [ABSTRACT FROM AUTHOR]

Wang, L.; Coles, N.; Wu, C., and Wu, J., 2014. Effect of long-term reclamation on soil properties on a coastal plain, southeast China. The coastal plain of Cixi City, in southeast China, has experienced more than a thousand years of land reclamation history. Since 1047, 11 dikes have been built, dividing our study region into 11 zones. The main aim of this study was to evaluate the effects of long-term reclamation on the variability of soil properties. Using an integrated transect and nested sampling approach, a total of 329 surface soil samples were collected. Soil pH, organic matter, electrical conductivity, and particle size distribution were measured. Data were evaluated using classical statistics and geostatistics methods. Results indicate that reclamation exerted quantifiable effects on various soil attributes. There were significant differences in soil properties among the zones. The ranges in semivariograms were approximately equal to or twice the average zone span, suggesting that there was usually a break in continuity of soil properties at the boundary of reclamation zones. As illustrated by the lower nugget effect or larger range distance in semivariograms, soil pH, electrical conductivity, and organic matter similarly showed more continuous patterns in space compared with particle size distribution. With the increase of time since reclamation, salt content, alkalinity, and particle size tended to decrease, while organic matter content tended to increase. Most properties varied greatly in the initial reclamation stages. A relatively steady state was reached within 10 years following the reclamation for pH, about 30 years for organic matter, and 60 years for electrical conductivity, respectively. Further, similar land uses and parent materials produced similar inherent soil properties. These findings can be applied to broader spatial scales in other coastal regions to assist in transitioning from a coastal tidal plain to productive agricultural land, through reclamation, and targeted land management practices. [ABSTRACT FROM AUTHOR]

This article investigates the dynamic relationship between economic development and the identification of ethnic minorities and argues that identification of China's ethnic minorities manifests itself at various levels. At the national level, the introduction of market mechanisms and economic growth initiatives have been concentrated predominantly in the coastal areas and metropolises, and are thus increasingly distant from ethnic minorities, a disproportionate majority of which reside in the western parts of the country. This growing regional disparity has placed ethnic regions and populations in a distinctly unfavourable position in terms of economic engagement and development. Regional development in the ethnic-minority homelands has been characterized by the representation and reinvention of ethnic cultural traditions and the production of cultural economies. Unequal economic growth has resulted in a massive migration of ethnic minorities to the cities. Simultaneously, urban development has reinforced ethnic identity, particularly through urban labour-market development. Urban and regional development has, in turn, led to the production, activation and magnification of ethnic identity at individual and group levels. [ABSTRACT FROM AUTHOR]

Spatial patterns of phytoplankton across the southern Taihu basin of China were examined through five aspects: abundance, composition, richness, evenness and diversity. Data were collected from 33 sites in the 2010 dry (April) and wet (July) seasons. Global Moran's I statistics and Local Indicators of Spatial Association were used to characterize the spatial autocorrelation for phytoplankton patterns. The phytoplankton pattern was found to have significant spatial autocorrelation in both seasons. Specifically, the wet season showed more local patterns of richness and more regional evenness patterns. Spatial regression models were carried out to identify environmental factors that would control phytoplankton patterns. Results showed that diversity and composition of phytoplankton were significantly related to nutrients. Also, phytoplankton richness could be predicted by potassium permanganate. No significant relationships were identified between environmental factors and phytoplankton evenness in both seasons. Our study highlighted the importance of incorporating spatial dependence when identifying the explanatory environmental factors for phytoplankton patterns. [ABSTRACT FROM AUTHOR]

This study employed spatial regression to analyze the determinants of dissolved oxygen (DO) and nutrients in the Qiantang River, China. Determinants of their spatial patterns in 1996 and 2003 as well as their dynamics during this time period were characterized at sub-basin and 500-m riparian buffer scales. Results indicated that the determinants differed by variable and by scale. Built-ups, farmland, water body, population density and gross domestic product were positive indicators for nutrient pollution and hypoxia, while distance to river source and forest were negative indicators. Higher slope variability indicates more DO and nutrients. In addition, built-up increases that were accelerated by population growth and economic development accounted for DO and nutrients dynamics to a large extent. This study highlighted that incorporation of spatial autocorrelation into regression was not only a methodological advantage but also a promising management tool. [ABSTRACT FROM AUTHOR]

DEMs as important input parameters of environmental risk assessment models are notable sources of uncertainties. To illustrate the effect of DEM grid size and source on model outputs, a widely used watershed management model, the Soil and Water Assessment Tool (SWAT), was applied with two newly available DEMs as inputs (i.e. ASTER GDEM Version 1, and SRTM Version 4.1). A DEM derived from 1:10,000 high resolution digital line graph (DLG) was used as a baseline for comparisons. Eleven resample resolutions, from 5 to 140 m, were considered to evaluate the impact of DEM resolution on SWAT outputs. Results from a case study in South-eastern China indicate that the SWAT predictions of total phosphorus and total nitrogen decreased substantially with coarser resample resolution. A slightly decreasing trend was found in the SWAT predicted sediment when DEMs were resampled to coarser resolutions. The SWAT predicted runoff was not sensitive to resample resolution. For different data sources, ASTER GDEM did not perform better than SRTM in SWAT simulations even it was provided with a smaller grid size and higher vertical accuracy. The predicted outputs based on ASTER GDEM and SRTM were similar, and much lower than the ones based on DLG. This study presents potential uncertainties introduced by DEM resolutions and data sources, and recommends strategies choosing DEMs based on research objects and maximum acceptable errors. [ABSTRACT FROM AUTHOR]

Abstract: Real time and spatially distributed T a (air temperature) data are desired for many applications. T s (land surface temperature) derived from remote sensors has been used to estimate T a in previous studies. Exploring MODIS Aqua T s and station measured daily maximum and minimum T a over east Africa, we found that T s did not agree well with T a during the day (MAE (Mean Absolute Error)=6.9±5.0°C) but had better agreement during the night (MAE=1.9±1.7°C). A stepwise linear regression method was applied to construct possible models to predict T a based on MODIS data. Our results showed that, only considering elevation, high spatial resolution T a could be obtained by simple linear models, with MAE=1.9°C, agreement index=0.79 for daily maximum T a, and MAE=1.9°C, agreement index=0.92 for daily minimum T a. MODIS T s data could provide temporal variation information and slightly improve the accuracy of model predictions (by 0.2°C of MAE). However, considering (i) major absences (about 2/3 of days) of T s data due to cloud cover and (ii) small T a variations in time (σ =2.1°C) over east Africa, models without T s might be more practical in particular applications such as tsetse fly distribution models. Other variables including solar zenith angle, low level precipitable water content, and vegetation index (NDVI and EVI) were insignificant in the daily maximum and minimum T a estimation models after elevation and T s had already been considered as predictors. [Copyright &y& Elsevier]

Soil erosion, as a serious environmental problem worldwide, poses a great threat to human sustainability. Spatiotemporal information on soil erosion is of vital importance to finding a solution for this problem. A case study was conducted to characterize the dynamics of soil erosion risk in 1985, 1994, 2003 and 2008 for Anji County, China, a region with seemingly high ecological quality. Remote sensing and geographic information systems were integrated to parameterize soil erosion-controlling factors. By using the Revised Universal Soil Loss Equation, we estimated annual soil loss, and generated categorical maps of soil erosion risk in the County for the 4 years. Results showed that, while appearing to improve in some areas, soil erosion risk increased and eroded area expanded from 1985 to 2008. Spatial analysis revealed that the most vulnerable hotspots were erosion-free forests, where newly eroded areas were most likely to occur. These results implied that, similar to findings in many parts of the world, soil erosion is an important issue in the study area, which could be closely associated with local eutrophication and algal blooms. Our research indicated that there should be more focus on this issue. From a methodological point of view, we believe that the approach used to estimate soil loss in the study area has the potential to be applied in other similar regions. [ABSTRACT FROM AUTHOR]

Assessing agroecosystem health at landscape scale has been rarely reported. A geospatial assessment framework, by integrating remote sensing, geographical information systems, landscape metrics, geostatistics and catastrophe theory, was proposed and applied to characterize the spatial variations of agroecosystem health for a typical region in the eastern coastal agricultural plain, China. After appropriate pretreatments, eleven hierarchically structured indicators, subject to catastrophe models, were aggregated into an integrated index for each 30 m grid cell across the study area. Great spatial variations in agroecosystem health were identified. Areas covered by water bodies and impervious surfaces, under which soils can not function, generally presented low values. Larger slope or higher heavy metal polluted areas and those near roads showed low or moderate values of agroecosystem health index. Concerning the spatial variations of agroecosystems health, patches of approximately 4 km in diameter were identified, within which more homogenous patterns would be expected. Specifically, the spatial variations of agroecosystems health should be resulted from the location-specific coupled influences of the underlying indicators. The integrated agroecosystem health index is believed to be helpful for managers to promote environmental management. The geospatial assessment framework reported in this paper was simple and operational, and has potential to be applicable to other areas with similar conditions at landscape scale. [ABSTRACT FROM AUTHOR]

Aims Related transcription enhancer factor-1 (RTEF-1) has previously been demonstrated to play an important role in both endothelial cells and cardiomyocytes. However, the function of RTEF-1 in the communication between these two adjacent cell types has not been elucidated. Methods and results We have found that endothelium-specific RTEF-1 transgenic mice (VE-Cad/RTEF-1) developed significant cardiac hypertrophy after transverse aortic constriction surgery, as evidenced by an increased ratio of heart weight to tibia length, enlarged cardiomyocyte size, thickened left ventricular wall and elevated expression of hypertrophic gene markers, with up-regulation of vascular endothelial growth factor B (VEGF-B). Additionally, VEGF-B was increased in endothelial cells from VE-Cad/RTEF-1 mice, as well as in endothelial cells with forced RTEF-1 expression (HMEC-1/RTEF-1), and coincidentally decreased when RTEF-1 was deficient in HMEC-1. Using chromatin immunoprecipitation and luciferase assays, we found that RTEF-1 increased VEGF-B promoter activity through a direct interaction. Hypertrophy-associated genes and protein synthesis were up-regulated in cardiomyocytes that were incubated with conditioned medium from HMEC-1/RTEF-1 and the endothelial cells of VE-Cad/RTEF-1 mice. This effect could be abrogated by treating the myocytes with VEGF-B small interfering RNA and extracellular signal-regulated kinase 1/2 inhibitor. Conclusion Our data demonstrated that increased RTEF-1 in endothelial cells upregulates VEGF-B, which is able to stimulate hypertrophic genes in cardiomyocytes. These results suggest that the RTEF-1-driven increase of VEGF-B plays an important role in communication between the endothelium and myocardium. [ABSTRACT FROM PUBLISHER]

This study compared the ability of Sargassum fusiforme to accumulate As, Cd, Cr, Cu, Ni, Pb and Zn in its five tissues (main branch, lateral branch, leaf, receptacles and pneumathode). The concentrations of these trace elements in seawater, surface sediments and different tissues of S. fusiforme were analyzed in different areas in Dongtong County (Wenzhou City, China). The presence of receptacle at all sites indicated that S. fusiforme had entered the mature stage. However, the proportion of each tissue in S. fusiforme in different sites was varied, indicating subtle differences in growth. S. fusiforme has a great capacity to accumulate trace elements, showing relatively high levels of As (28.2–64.2 mg kg−1) and Zn (19.9–80.8 mg kg−1). The elements are mainly stored in leaf, receptacles and pneumathode. Compared to element concentrations in the surrounding environment, the seaweed exhibited stronger bioconcentration capacity for As and Cd than for other elements. According to our health risk assessment results, the hazard index and carcinogenic risk were below the limit, suggesting that the S. fusiforme ingestion would not pose any health risk and the potential risk of intake branches was even lower than that of other tissues. • S. fusiforme showed high levels of As and Zn. Elements were mainly accumulated in receptacles, leaf and pneumathode. • S. fusiforme can accumulate high levels of trace elements from surrounding environment, especially As and Cd. • Potential health risks of consuming branches are lower than that of other tissues. [ABSTRACT FROM AUTHOR]

Spartina alterniflora has extensively invaded the coastline of China, including in Maoyan Island of Zhejiang Province. Ecological restoration has been conducted using non-native mangrove Kandelia obovata to replace S. alterniflora in an attempt to restore the impacted intertidal zones. To illustrate the ecological effectiveness of the restoration projects, macrobenthos communities were studied among different habitats within the restored areas, including one non-restored S. alterniflora marsh (SA) and three differently-aged restored K. obovata stands planted in 2003, 2009, and 2011 respectively (KF14, KF8, and KF6). Besides, one unvegetated mudflat (MF) adjacent to the non-restored S. alterniflora marsh and one K. obovata forest transplanted in 2006 (RKF) at a previously barren mudflat without invasion history of S. alterniflora were set as reference sites. A total of 69 species of macrobenthos were collected from Maoyan Island, and the species richness was dominated by gastropoda (23 species), polychaeta (18 species), and malacostraca (16 species). There was no significant difference between the six sites in terms of the abundance of macrobenthos, with the average values of abundance peaking in KF6 (734.7 ind m−2) and being lowest in RKF (341.3 ind m−2). The six sites had significant differences in terms of the biomass of macrobenthos. The KF8 site contained the highest average biomass (168.3 g m−2), whereas the MF site had the lowest (54.3 g m−2). The Shannon-Wiener diversity index and Pielou's evenness index of the macrobenthos did not exhibit significant differences among the six sites. However, the results of permutational multivariate analysis of variance (PERMANOVA) revealed significant spatial differences in the macrobenthos community structure between the sites. Since KF14 shared a similar macrobenthos community structure with RKF, while representing a strikingly different structure from SA, we infer that ecological restoration using K. obovata can restore the macrobenthos community to resemble to a normally planted K. obovata forest about 15 years after restoration. [ABSTRACT FROM AUTHOR]