Salt ions accumulation and distribution characteristics of pioneer plant species at a bauxite residue disposal area, China

Bauxite residue disposal areas(BRDAs)are physically degraded and hostile to plant growth.Nevertheless,natural plant colonization was observed in an abandoned BRDA in Central China.The pioneer plant species at the disposal area were identified,whilst distribution characteristics of salt ions such as Na^+,K^+,and Ca^2+in plant tissues and rhizosphere residues were investigated.The mean concentration of exchangeable Na^+in the rhizosphere soils was 19.5 cmol/kg,which suggested that these pioneer plants had relatively high salinity resistance.Sodium content varied from 0.84 cmol/kg(Digitaria sanguinalis)to 39.7 cmol/kg(Kochia scoparia),whilst K to Na ratio varied from 0.71(Myricaria bracteata)to 32.39(Digitaria sanguinalis)in the shoots,which demonstrated that the salinity tolerance mechanisms of these pioneer species differed significantly.Accumulation factors of Na^+in local plant species ranged from 0.04(D.sanguinalis)to 3.29(M.bracteata),whilst the translocation factor varied from 0.13(D.sanguinalis)to 2.92(M.bracteata).The results suggested that four pioneer plant species including K.scoparia,M.bracteate,Cynodon dactylon and D.sanguinalis could be suitable for revegetation at other disposal areas.

Regional-scale investigation of salt ions distribution characteristics in bauxite residue: A case study in a disposal area

Revegetation on bauxite residue disposal areas is the most promising strategy to reduce its potential ecological risk during stacking or disposing.Migration of salt ions in bauxite residue is one of the major issues to stimulate soil formation to support plant growth.21 residue samples were collected and the related parameters including exchangeable cations,soluble ions,total salt,pH,electrical conductivity(EC)and exchangeable sodium percentage(ESP)were selected to evaluate alkalization and salinization of bauxite residue.High levels of ions,cation exchange capacity(TOC),total salt,exchangeable sodium percentage(ESP)and cation exchange capacity(CEC)in bauxite residue were detected with greater coefficient of variation(CV),which indicated that distribution characteristics of salt ions varied significantly.The percentage of sulfate-chloride-soda type in the residues accounted for 71.43%.The mean value of pH was 10.10,whilst mean value of ESP was 52.05%.It indicated that the residues in this case study belonged to sulfate-chloride-soda saline and alkaline soil.The research results could provide theoretical basis for soil formation in bauxite residue.

Dynamic change and diagnosis of physical, chemical and biological properties in bauxite residue disposal areas

Vegetation encroachment occurred in bauxite residue disposal area(BRDA)following natural weathering processes,whilst the typical indicators of soil formation are still uncertain.Residue samples were collected from the BRDA in Central China,and related physical,chemical and biological indicators of bauxite residue with different storage years were determined.The indicators of soil formation in bauxite residue were selected using principal component analysis,factor analysis,and comprehensive evaluation to establish soil quality diagnostic index model on disposal areas.Following natural weathering processes,the texture of bauxite residue changed from silty loam to sandy loam.The pH and EC decreased,whilst porosity,nutrient element content and microbial biomass increased.The identified minimum data set(MDS)included available phosphorus(AP),moisture content(MC),C/N,sand content,total nitrogen(TN),microbial biomass carbon(MBC),and pH.The soil quality index of bauxite residue increased,and the relative soil quality index decreased from 1.89 to 0.15,which indicated that natural weathering had a significant effect on improveing the quality of bauxite residue and forming a new soil-like matrix.The diagnostic model of bauxite residue was established to provide data support for the regeneration on disposal area.

On area-specific underground research laboratory for geological disposal of high-level radioactive waste in China

Underground research laboratories （URLs）, including ＂generic URLs＂ and ＂site-specific URLs＂, are un- derground facilities in which characterisation, testing, technology development, and/or demonstration activities are carried out in support of the development of geological repositories for high-level radioactive waste （HLW） disposal. In addition to the generic URL and site-specific URL, a concept of ＂areaspecific URL＂, or the third type of URL, is proposed in this paper. It is referred to as the facility that is built at a site within an area that is considered as a potential area for HLW repository or built at a place near the future repository site, and may be regarded as a precursor to the development of a repository at the site. It acts as a ＂generic URL＂, but also acts as a ＂site-specific URL＂ to some extent. Considering the current situation in China, the most suitable option is to build an ＂area-specific URL＂ in Beishan area, the first priority region for China＇s high-level waste repository. With this strategy, the goal to build China＇s URL by 2020 mav be achieved, but the time left is limited.

基于AI的多模态融合感知综合决策系统设计实现

针对传统军事要地安防系统智能化程度较低,各自独立互不关联,缺少顶层数据综合治理等问题,选取外围周界、重要卡口、无人巡更和区域高点四种典型安防业务场景开展建模,通过数据标准化接入、智能研判分析、安防态势显示三个处理环节,构建基于AI的多模态融合感知综合决策系统,实现前端感知多维化、中台研判智能化、后端处置多样化,有效支撑了重要军事目标安全防卫,系统后续也具有良好的可扩展性与可维护性。

Estimation of Fracture Geometry Parameters and Characterization of Rock Mass Structure for the Beishan Area,China

The accurate estimation of fracture geometry parameters and the characterization of rock mass structure are two important topics in the geological disposal system of high-level radioactive waste(HLW).The Beishan area,as the current preselected area for China’s HLW disposal,has three subareas considered to be the key survey area at the stage of site selection.In this paper,a comprehensive survey method conducted on the outcrop is developed to estimate fracture geometry parameters.Results show that fracture occurrence obeys a Fisher distribution,fracture trace length obeys a normal distribution,and the distribution of spacing obeys a negative exponential distribution.An evaluation index,Rock Mass Structure Rating(RMSR),is proposed to characterize rock mass structure for the three subareas.The results show that the Xinchang area is more suitable to act as China’s HLW disposal repository site.At the same time,the index can also be applied to characterize surface rock mass structure and rock mass integrity at the site selection phase of HLW disposal.

乡村产业振兴的农民农村共同富裕效应

实现农民农村共同富裕面临着农民增收渠道少和持续性差等现实问题,以及城乡收入差距、区域收入差距和农村内部收入差距三大挑战,乡村产业振兴为解决这些问题提供了新思路。使用2011—2020年中国30个省份的面板数据,采用FGLS和PCSE回归方法实证检验了乡村产业振兴对农民农村共同富裕的影响。研究结果表明,加快乡村产业振兴有助于实现农民可支配收入增长和农民三大收入差距缩小兼得的共同富裕效应,这一结论在经过内生性和稳健性检验后依然成立。进一步研究发现,乡村产业振兴对农民工资性收入和经营净收入的促进作用明显大于对转移性收入和财产性收入的促进作用,对缩小城乡收入差距的作用大于对缩小区域收入差距和农村内部收入差距的作用。异质性分析发现,在乡村产业振兴高水平地区,乡村产业振兴可以促进农民可支配收入增长和缩小三大收入差距,即可实现富裕效应和共同效应;在乡村产业振兴低水平地区,乡村产业振兴仅对农民可支配收入增长和城乡收入差距产生显著影响。

低温菌剂在农村粪污及污水处理中的研究进展

农村厕所粪污与污水的有效处理是农村厕所改造的关键,也是推动中国乡村振兴的重要内容。中国北方地区冬季气候寒冷,为粪污与污水妥善处置带来极大挑战。生物法是农村厕所粪污、污水处理的主要方法和手段,黑龙江地处寒温带,年平均气温4℃,低温条件抑制生物活性,导致污染物去除效能大幅降低。低温菌剂是由低温驯化或定向筛选得到的具有特定功能的耐低温微生物复配体,为寒冷地区粪污处置和污水处理提供了有效、绿色、经济的解决思路和方法。文章系统介绍了耐低温微生物对寒冷环境的耐受机制,阐述了在寒冷条件下,低温菌剂在粪污处置与污水处理中的研究现状和工程应用,总结了低温菌剂在提高污染物处理效率、促进污染物降解和资源转化利用方面的进展,并对未来低温菌剂在粪污及污水处理领域的发展进行了展望。

弃土场原位与弃土斜坡水分运动特征对比分析

降雨入渗会改变斜坡原有的平衡状态,为探究弃土场原位与弃土斜坡降雨入渗过程的水分运动特征。以某弃土场为研究对象重复开展染色示踪试验,对比分析原位与弃土斜坡垂直方向上土壤剖面的染色面积比和渗流前后水分运动特征的差异。结果表明(1)原位斜坡水分入渗以基质流为主,少量优先流动由生物通道引发;0~50 cm深度水分垂直均匀入渗程度高,随深度增大,表现出沿容重小一侧非均匀流动;50 cm深度以下,平均染色面积比与深度呈负相关;(2)无植被发育弃土斜坡无优先流动,沿斜坡土体表层水平扩散流动程度高,平均染色面积比在20 cm深度以下保持为0,无染色特征;植被发育弃土斜坡水分沿植物根茎优先入渗,垂直入渗较活跃;(3)染色面积比及湿润带特征能很好的捕捉斜坡水分渗流的非均匀信息;同时,根系会改变土体的孔隙发育程度,形成内部交织的网状结构,降低土壤容重,增加水分入渗,有利于增强表层土壤含水率,降低水分深层渗流,增强斜坡稳定性;加强弃土场植被生态恢复有利于增加斜坡的固土保水能力及稳定性。

弃渣扰动对藏东山地草甸坡面产流产沙的影响

[目的]明晰铁路修建中弃渣工程扰动引起的水土流失响应,揭示弃渣堆积前后及其植被恢复对藏东生态脆弱的山地草甸区坡面尺度水土流失的影响。[方法]选取未扰动、轻度扰动、重度扰动、覆土恢复4个类型的坡面,建立原位径流小区,通过人工模拟降雨试验,开展了坡面产流产沙过程的研究。[结果](1)坡面的溅蚀量随扰动强度的增大而增加,下坡向的溅蚀量为上坡溅蚀量的1.14~2.67倍。(2)轻度扰动坡面、重度扰动坡面和覆土恢复坡面的初始产流时间分别缩短为未扰动坡面的53.8%~66.7%,34.6%~46.7%,86.7%~92.9%。(3)未扰动坡面、轻度扰动坡面、重度扰动坡面和覆土恢复坡面的产流速率分别为44~86,104~147,200~373,46~95 ml/(min·m^(2)),产沙速率分别为0.026~0.055,0.05~0.098,1.034~2.189,0.047~0.077 g/(min·m^(2))。[结论]覆土恢复坡面的水土保持能力较轻度扰动和重度扰动坡面有显著提高,但距未扰动坡面仍有差距,需采取其他植被或工程措施对工程扰动坡面加以恢复。

火力发电厂贮灰场封场与再利用国内外现状

燃煤发电厂每年排放数量巨大的粉煤灰,需要建设贮灰场加以贮放。随着我国粉煤灰贮存量的增加,及在国家“十四五”规划能源结构调整和倡导生态环保发展的大背景下,越来越多的贮灰场面临封场与再利用。本文在搜集整理的资料基础上,对我国贮灰场封场与再利用的现状及国内外相关标准等进行分析,并对我国贮灰场封场与再利用面临的主要问题进行了探讨。最后结合我国贮灰场封场与再利用的实际情况,并借鉴相近行业和国外贮灰场封场标准,建议建立我国的贮灰场封场与再利用标准,加强封场贮灰场固碳可行性论证。

电子商务促进了农民农村共同富裕吗?——基于收入增长与差距缩小的双重视角

电子商务促进了农民与市场的有效连接,带动了农民就业创业增长,并弱化了低收入农民的信息劣势,可以同时提高农民收入水平和缩小农民收入差距,赋能农民农村共同富裕。利用我国1 996个区县2014—2020年的面板数据以及CHIP 2018的农户数据,基于人均可支配收入和基尼系数综合评价农民农村共同富裕程度,以淘宝村数量衡量农村电商发展水平,运用双向固定效应模型和RIF回归分析发现:淘宝村数量增加提高了农民的人均可支配收入,并降低了农民的基尼系数,显著促进了农民农村共同富裕;电子商务主要通过促进农民创业和经营性收入增长的路径来增加农民收入,而对农民就业及其工资性收入的影响不显著;农村电商发展对农民收入增长的促进作用在收入水平较低区县、国家级贫困县、离中心城市较远区县、中西部区县更强。因此,应当加快欠发达地区及偏远地区的农村电商发展,加强对低收入农民的扶持和帮助,提高电子商务的益贫性和普惠性,有效促进农民农村共同富裕。

Utilization of recycled solid waste as ecological reclamation materials based on plant growth experiments and soil quality analysis

During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally utilized.Besides,the vegetation recovery is slow in the spoil areas due to the soil depletion.Aiming at recycling the solid waste,the sieved engineering waste slag with local red clay and corn straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and soil.In addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha fruticosa L.combined with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil areas.The results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar content.The improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag content,especially when the soil-slag ratio is less than 3,and the promotion of plants is limited.On the contrary,the improvement effect is proportional to the biochar content(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit corresponding to the Nemero soil pollution index level when the biochar content is 8%.Therefore,it is recommended that the soil-slag ratio should be≥3,and the biochar content should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas.

岩溶区排泥库泥浆泄漏应急处置管理经验探讨

岩溶区排泥库具有尾矿粒度细和地质条件复杂两大特点,致使近年来泥浆泄漏事故频发。泥浆通过岩溶通道外泄至周边水系,污染下游河道、水塘、泉眼等,对库区周边生态环境及居民生产、生活造成极坏的负面影响和极大的经济损失。如何有效应对甚至避免该类事故,成为工程技术人员、厂矿企业及地方政府密切关心的问题,也给排泥库设计、建设及管理人员提出极大的挑战。针对排泥库的泄漏特点和应急处置难点,系统分析排泥库从选址、设计、施工至运行全寿命周期过程中所应关注的重点,包括地质勘察、岩溶治理、应急管理体系、泄漏点处置及应急池建设等。结合近年来排泥库建设、管理过程中总结、积累的相关经验,同时借鉴行业专家针对尾矿库突发事件的应急处置经验,提出了排泥库泄漏应急处置管理应具备的全新理念。并通过工程案例,明确排泥库泥浆泄漏应急处置管理的重点、难点,以及具体实践过程中可参考的思路和方法,对提高排泥库应急处置管理水平和化解泥浆泄漏风险具有较大的现实意义。

拉林铁路弃渣场水土保持型生态恢复技术探讨

为研究高寒高海拔地区铁路建设项目弃渣场的生态恢复措施,该文以拉(拉萨)林(林芝)铁路工程为依托,结合青藏高原的地域条件探讨弃渣场的水土保持型生态恢复技术。研究得到以下结论,根据恢复区立地条件,系统阐明弃渣场的选址原则及水土保持型生态恢复理论;基于物种选择原则和防护措施设计建立适应于青藏高原地区的水土保持型生态恢复技术。研究成果可为该地区铁路工程建设项目的弃渣治理提供一定的借鉴意义。

竖向扩建飞灰填埋库区的中间衬垫系统优化设计

填埋场竖向扩建飞灰填埋库区面临因整体沉降、不均匀沉降带来的中间衬垫系统设计难题。通过梳理沉降计算方法,提出一种具有12层结构的中间衬垫系统优化结构,该结构能够同时起到防渗隔离、抵抗不均匀沉降和导排底部填埋气的作用,与浙江省某填埋场的中间衬垫系统相比具有优越性。

双碳目标约束下现代煤化工企业绿色低碳发展路径浅析

我国现代煤化工产业规模不断扩大,政策导向作用愈加明显,产业布局结构逐步优化,煤炭清洁高效利用水平不断提升。与此同时,在“双碳”目标约束下,如何做到降碳、减污、扩绿、增长,实现经济高质量发展,成为整个行业面临的重要问题。现代煤化工企业要探索多端降碳路径,从源头、工艺过程及末端“三箭齐发”;坚持清洁利用,持续探索“三废”的处置与利用途径;开辟碳中和扩绿路径,增加林草碳汇,发展富碳农业,实施生物质资源化利用;坚持多元化发展,积极拓展低碳循环增长路径,推动行业耦合发展和产业链延伸,开发高端减碳新产品。由此形成可复制可推广的现代煤化工四位一体的协同发展模式,最终实现我国现代煤化工产业发展与降碳的双赢。

某高速公路弃渣场设计与稳定性分析

基于西南地区某高速公路新建沟道型、2级防护、堆放高度35.00 m的弃渣场,设计并验算弃渣场的排水系统,论证弃渣场建成后河道排洪的合理性及安全性,并进行整体稳定性分析。结果表明:弃渣场排水沟尺寸能满足100年一遇洪水过流要求,且至少有0.66 m安全超高;弃渣场边坡整体处于稳定状态;在地震工况下边坡处于欠稳定-基本稳定状态,弃渣体前缘临空面高6.00 m,最大剩余推力848.6kN/m,设计采用抗滑桩进行支挡防护。

中国海油溢油处置能力的建设现状及挑战

中国海油高度重视海上油气生产安全,为了有效应对海上溢油事故,中国海洋石油集团有限公司建立了一套海上溢油应急体系,随着中国海油勘探开发的规模逐渐增大,海上油气开发生产方式及油气种类日益增多,特殊区域溢油特殊种类原油泄漏处置方法与一般溢油事故有所不同。文章结合中国海油海上油气开发前沿和中国海油现有海上溢油处置能力建设现状,探讨特殊环境特殊种类原油溢油事故的特点及处置难点,并与现有溢油处置能力对比,分析两者差距,以期为中国海油海上溢油事故处置能力建设提供参考和支持。

多种堆载方式对弃渣场稳定性的探究

为了研究弃渣场边坡在不同堆载方式下的稳定情况,以某高原铁路弃渣场边坡作为研究对象,通过现场调研、Midas GTX NX数值模拟等方式,研究了弃渣场边坡在多种堆载方式下的应力、应变和安全系数变化情况,探明了弃渣场在堆载完成后只受重力的作用下的稳定性状况。结果表明:顺排压坡脚(现场布置平滑)方式具有最好的稳定性;覆盖式稳定性较差;堆载完的渣场在自身重力情况下即可处于稳定状态。