Spatial distribution prediction and benefits assessment of green manure in the Pinggu District,Beijing,based on the CLUE-S model

Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways（i.e.,intercropping green manure in orchards or rotating green manure in cropland） to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent（CLUE-S） model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics（mainly croplands and orchards） were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011：The promotion of green manure planting in orchards（scenario 1） and the promotion of simultaneous green manure planting in orchards and croplands（scenario 2）.The predictions were generally accurate based on the receiver operating characteristic（ROC） and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways.

Assessment of spatial and seasonal water quality variation of Oum Er Rbia River(Morocco)using multivariate statistical techniques

The aim of this study is to assess the spatial and temporal water quality variation and to determine the main contamination sources in the Oum Er Rbia River and its main tributary,El Abid River.The water quality data were collected during 2000-2012 from fourteen sampling stations distributed along the river.The water quality indicators used were TEMP,pH,EC,turbidity,TSS,DO,NH_(4)^(+),NH_(3)^(-),TP,BOD5,COD and F.coli.The water quality data was analyzed using multivariate statistical methods including Pearson's correlation,PCA,and CA.The results showed that in some stations the water quality parameters were over Moroccan water standards.PCA applied to compare the compositional patterns among the analyzed water samples,identified and four factors accounting for almost 63% of the total variation in the data.This suggests that the variations in water compounds’concentration are mainly related to point source contamination(domestic and industrial wastewater),non-point source contamination(agriculture activities),as well as natural processes(weathering of soil and rock).CA showed relatively spatial and seasonal changes in surface water quality,which are usually indicators of contamination with rainfalls or other sources.Overall,this study showed that the water was potentially hazardous to health of the consumers and highlighted the need to treat industrial and municipal wastewater and to encourage sustainable agricultural practices to prevent adverse health effects.We therefore suggest wise management of anthropogenic activities in the catchment of Oum Er Bia River and their tributaries.

Spatial distribution and pollution assessment of heavy metals in urban soils from southwest China

To identify the concentrations and sources of heavy metals, and to assess soil environmental quality, 63 soil samples were collected in Yibin City, Sichuan Province, China. Mean concentrations of As, Pb, Zn, and Cu were 10.55, 61.23, 138.88 and 56.35 mg/kg, respectively. As concentrations were comparable to background values, while Pb, Zn, and Cu concentrations were higher than their corresponding background values. Industrial areas exhibited the highest concentrations of As, Pb, Zn, and Cu, while the lowest concentrations occurred in parks. Statistical analysis was performed and two cluster groups of metals were identified with Pb, Zn, and Cu in one group and As in the other. Spatial distribution maps indicated that Pb, Zn, and Cu were mainly controlled by anthropogenic activities, whereas As could be mainly accounted for by soil parent materials. Pollution index values of As, Pb, Zn, and Cu varied in the range of 0.24-1.93, 0.66-7.24, 0.42-4.19, and 0.62-5.25, with mean values of 0.86, 1.98, 1.61, and 1.78, respectively. The integrated pollution index （IPI） values of these metals varied from 0.82 to 3.54, with a mean of 1.6 and more than 90% of soil samples were moderately or highly contaminated with heavy metals. The spatial distribution of IPI showed that newer urban areas displayed relatively lower heavy metal contamination in comparison with older urban areas.

Spatial distribution and pollution assessment of mercury in sediments of Lake Taihu,China

Spatial distribution patterns of total mercury （THg） in 36 surficial sediment samples representing five regions of Lake Taihu were assessed using the ArcGis geostatistical analyst module. The pollution levels of THg were also evaluated from the same five lake regions. Concentrations of THg were in a ranged of 23-168 ng/g （mean 55 ng/g） in surfical sediments, which was significantly higher than those established baseline levels of the lake. Results of THg indicated that the northern region exhibited notably higher values, the bay regions showed elevated values relative to open areas, and the lakeside regions were higher than those observed in the central area. Lake Taihu suffered moderate to high Hg pollution, and expressed clear Hg enrichment status according to monomial pollution index I geo and human activity factors. The concentrations of THg in the surficial sediments of Lake Taihu showed moderate-strong variation （coefficient of variation 52%）. Geostatistical analysis indicated a weak spatial self-correlation, suggesting the contamination of Hg in Lake Taihu is primarily the result of anthropogenic activities.

A new tool for monitoring brain function: eye tracking goes beyond assessing attention to measuring central nervous system physiology

Concussion and other forms of brain injury are not always detectable with conventional means such as radiographic imaging.The lack of accurate diagnostics,biomarkers,and outcome measures has a devastating impact.Individual patients may suffer in obscurity,self-medicate into an addictive spiral,have impaired professional activity,and develop failed interpersonal relationships.

评估全球自然对人类的贡献

自然对人类的贡献(nature’s contributions to people,NCP)是指大自然对人类生活质量的一切积极贡献和消极影响,分为10个调节型NCP、4个物质型NCP和4个非物质型NCP.但目前这些NCP的全球时空分布及其相互作用规律尚不清楚,直接制约了加强自然界多种有益贡献的生态系统管理实践.本研究构建基于指标体系的评价方法,结合生态系统演变、气候变化与人类活动全球尺度多源空间数据集,在全球范围内对1990~2018年所有18个NCPs进行空间制图,在15,204个流域单元上识别主导了NCP组合,并基于NCPs时空特征识别了全球景观变化的功能权衡关系和景观多功能性.结果表明,全球大部分NCPs的高值仅在局地出现.1992~2018年,6个调节型NCP、3个物质型NCP和2个非物质型NCP下降.29种调节型和物质型NCP组合(总共有54种组合)的主导流域占全球76%的陆地面积,而无NCP主导的流域占全球陆地面积的22%.NCPs变化的协同关系比权衡关系更为常见,但调节型和物质型NCP之间的关系普遍处于权衡状态.过渡气候地区的NCP相对少,并具有强烈的权衡关系;而低纬度地区NCPs之间的高度协同关系可能受到未来气候变化的影响.研究结果提供了对全球NCP空间变化规律的总体认知,可用于科学支撑区域景观功能的关系调控和景观多功能性提升,以增强全球人类福祉.