Review of wastewater treatment technologies,soil and water conservation measures in nuclear power plants,and inspirations to Fukushima accident

[Background]The previous studies suggest that radioactive elements like Cs and Sr may adversely affect marine ecosystems and the fishing industry.Traditional treatment systems for radioactive wastewater like the Advanced Liquid Processing System(ALPS)and Kurion have faced challenges in limiting concentration and achieving safety criteria.Studies suggest potential long-term impacts on benthic organisms and seafood networks due to radioactive elements like Cs and Sr from the discharged radioactive wastewater,which may hinder post-disaster recovery and provoke economic losses in the fishing industry both domestically and internationally.A series of studies indicate that there are issues of Cs and Sr pollution migration in soil and water conservation in Fukushima.[Methods]To provide feasible solutions,the main article includes five nuclear wastewater treatment technologies,and soil and water conservation measures for different media(water and soil)were evaluated through reviewing the previous fifteen years'articles.To provide feasible solutions,the main articles,the phytoextraction technologies in Cs and Sr treatment within different land use areas were wildly analyzed(Camellia japonica,Arabidopsis halleri and other local species).[Results]1)A 99.9%removal rate for Cs^(+)and 99.5%for Sr^(2+)was achieved by the KFe[Fe(CN)_(6)]and BaSO_(4)co-precipitation method.2)For membrane filtration,Sr^(2+)and Cs^(+)were removed using metal-organic framework(MOF/graphene oxide)and ion exchange techniques using inorganic materials like titanosilicates.The absorption efficiency of membrane filtration for Sr^(2+)and Cs^(+)was at least 92%and 94%,respectively.The study analyzed soil and water conservation technologies in different land uses,river basins and catchments.3)The underground water treatment mainly were completed via the membrance technologies like reverse osmosis and Permeable Reactive Barriers(PRB)technologies.The ^(90) Sr concentration decreased 77%-91%compared to the initial concentration by PRB technology.These diverse methods offered effective strategies for radioactive wastewater treatment,especially the co-precipitation method may be feasible remediation measures to ensure ecological safety surrounding nuclear power utilizing areas.Soil and water conservation measures for soil pollution treatment mainly focused on the use of stabilizers to hinder the migration of Cs and Sr in the soil and the effects of wind erosion such as interpolyelectrolyte complexes.[Conclusions]We evaluated the pollution of Cs and Sr in the Fukushima nuclear radiation soil and water to provide solutions for the treatment of nuclear wastewater and to prevent radionuclide pollutants from migrating into the soil and water.

Study on the Forest Vegetation and Its Water and Soil Conservation Value in Fuxian Lake Drainage Area in Yunnan Province

By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a.

Study on Relative Soil and Water Conservation Benefits of Ridge Tillage in Different Terrain Conditions in the Black Soil Area of Northeast China

Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures.

SOIL EROSION AND THE WATER & SOIL CONSERVATION IN THE LOESSIAL HILLY AREA OF SOUTHERN NINGXIA

1. General Situation of Soil Erosion The loessial hilly area of southern Ningxia, Situated at the south of Ningxia Hui Au-tonomous Region, middle-upper reaches of the Yellow River, part of Chinese Loess Pla-teau, covers an area of 1500 square kilometers with an annual mean temperature of 5-8℃,a precipitation of 300-500mm of which 70% taking place concentratively during the peri-od between June and September in form of rainstorm, The annual evaporation

Gully Erosion Regionalization of Black Soil Area in Northeastern China

Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fertile farmland there. Regionalization of gully erosion can reveal the spatial distribution and regularity of the development of gully erosion. Based on the eco-geographical regional background features of the black soil area, this study combined the regionalization with influencing factors of the development of gully erosion. GIS spatial analysis, geostatistical analysis, spatial statistics, reclassification, debris polygon processing and map algebra methods were employed. As a result, the black soil area was divided into 12 subregions. The field survey data on type, length, volume and other characteristics indicators of gully erosion were used to calibrate the results. Then the features of every subregion, such as where the gully erosion is, how serious it is, and why it happens and develops, were expounded. The result is not only an essential prerequisite for gully erosion surveys and monitoring, but also an important basis for gully erosion prevention.

Changes in sediment discharge in a sediment-rich region of the Yellow River from 1955 to 2010: implications for further soil erosion control

The well-documented decrease in the discharge of sediment into the Yellow River has attracted considerable attention in recent years. The present study analyzed the spatial and temporal variation of sediment yield based on data from 46 hydrological stations in the sediment-rich region of the Yellow River from 1955 to 2010. The results showed that since 1970 sediment yield in the region has clearly decreased at different rates in the 45 sub-areas controlled by hydrological stations. The decrease in sediment yield was closely related to the intensity and extent of soil erosion control measures and rainstorms that occurred in different periods and sub-areas. The average sediment delivery modulus（SDM） in the study area decreased from 7,767.4 t/（km^2·a） in 1951–1969 to 980.5 t/（km^2·a） in 2000–2010. Our study suggested that 65.5% of the study area with the SDM below 1,000 t/（km^2·a） is still necessary to control soil deterioration caused by erosion, and soil erosion control measures should be further strengthened in the areas with the SDM above 1,000 t/（km^2·a）.

砒砂岩区生态治理-生态衍生产业协同发展关键技术与模式

探索生态治理与生态衍生产业协同发展的关键技术与途径,是促进水土保持生态治理高质量发展的重要课题。为此,以生态治理难度极大的黄河流域砒砂岩区为研究对象,基于生态经济学、生态产业技术的理论与方法,提出了生态治理-生态衍生产业协同发展的基本原理和应遵循的原则,探索了生态治理与生态衍生产业协同发展的关键技术与模式,并开展了示范应用。1)生态治理-生态衍生产业协同发展的原理是行为互驱动、效应互补偿,应遵循的原则是“双律适应、适地适生、三方意愿”;2)鉴于砒砂岩覆土区、覆沙区、裸露区生态环境有明显差异,分别构建了小流域生态治理-生态衍生产业协同发展的综合治理措施体系和模式,以坡顶、坡面和沟道为水土保持措施配置的3个地貌单元,选择兼具水土保持功能和饲用、药用、食用等经济开发价值的作物进行生物措施配置,配合注浆固结、抗蚀促生、砒砂岩改性等新的工程技术措施进行生态治理;3)研发了物理-化学-生物综合改良砒砂岩土壤、砒砂岩复配风沙土+生物改良提质、灌草优化平茬及饲料加工、煤矸石改性资源化利用、高陡边坡抗蚀+控渗+植生固稳、生态果园建植等关键技术;4)基于砒砂岩覆沙区“土壤改良固沙+”(如土壤改良固沙+经济林种植、土壤改良固沙+梭梭草套种甘草等)生态治理模式的实践与示范,探索实施了“政府支持,科技支撑,企业产业化+公益性投资,农牧民市场化参与”的多元投资、多方参与、共同受益运行机制与模式。通过灌草平茬饲料加工、土壤改良、经济作物种植等产业化中试,以及矿区回填区生态恢复、小流域生态治理-生态衍生产业协同发展示范性实践,表明脆弱生态区治理中发展生态衍生产业具有广阔的前景。

以确保“一泓清水永续北上” 引领南水北调中线水源区水土保持高质量发展

丹江口库区及上游是南水北调中线水源区(以下简称“水源区”),其水土保持高质量发展是保障“一泓清水永续北上”的重要支撑。文章针对水源区水土流失现状和特点,总结了丹江口库区及上游水土保持重点防治工程(以下简称“丹治”工程)实施以来的水土保持成效,分析了水土保持面临的新形势和新要求,梳理了水土保持存在的短板和不足,研究提出了引领丹江口库区及上游水土保持高质量发展的对策举措,为各级政府加强南水北调中线水源区水土保持治理管理提供参考。

夏县红沙河片区生态清洁小流域综合治理

红沙河片区存在河源区保护力度弱、沟道水系连通状况差、水资源和土地资源利用率低、农村基础设施差等问题。通过在预防保护区进行封禁治理,综合治理区布置坡改梯工程、保土耕作、林草工程、泉水利用工程等水保工程,同步推进面源污染防治、人居环境整治和文旅工程建设,生态修复区对赤峪河、吴家峪沟进行沟槽整治、边坡治理、岸边绿化等措施,将片区建设成为生态旅游型生态清洁小流域,可完善区内农业灌溉设施,提高了区内泉水利用率、土地生产力及沟道行洪能力,可有力促进当地特色产业、特色旅游业的发展,实现山青、水净、村美、民富的目标。工程建设亦可为同类工程建设提供借鉴和参考。

湖北省全口径水土流失治理现状调查及对策研究

当前,湖北省水土流失防治取得了显著成效,但成效仍不稳固,防治任务仍然繁重。建立规划实施监测评估机制,统筹区域全口径水土流失治理情况、跟踪规划实施情况,有利于切实提升区域水土流失治理效益,切实改善区域水土流失情况。收集整理了湖北省8个三级水土保持功能区内的典型县全口径水土流失治理措施实施相关情况以及各类项目图斑、竣工验收图和评估年卫星影像等资料,结合GF-1卫星遥感影像分析及无人机摄影测量等手段踏查治理图斑现场并矢量化治理图斑信息,完成了图斑现场信息化复核校验工作,基本摸清了2020年全口径新增水土流失治理任务分部门、分工程、分措施、分图斑分解落实情况。发现湖北省全口径水土流失治理措施图斑坐标准确率为96.13%、图斑有效率为93.22%、图斑完成率为97.37%,但部分项目进度存在一定滞后、田间配套设施配置不太完善、人为扰动风险仍居高位等实际困难。据此,提出了强化目标责任考核、健全监督检查和监理工作机制、推动防治工作统筹的对策建议,可为湖北省水土流失治理满足《全国水土保持规划(2015~2030年)》中制定的目标任务提供决策依据。

基于SOFM与随机森林的大别山区水土保持空间管控分区

水土保持是国家生态文明建设的重要内容,水土保持空间管控分区是水土流失区域科学治理的前提与关键。然而,目前水土保持管控区域划分研究还未形成成熟的空间划定方法,且以小流域为单元的水土保持空间管控研究较少。为探索水土保持空间管控分区的方法,落实差别化保护治理措施,该研究利用通用土壤流失方程(universal soil loss equation,USLE)计算研究区潜在土壤侵蚀模数与实际土壤侵蚀模数,并通过随机森林确定了土壤侵蚀的主要影响因子,基于小流域单元的土壤侵蚀及其影响因子利用自组织映射神经网络(self-organizing feature map,SOFM)确定了大别山区的水土保持空间管控分区。结果显示:1)大别山区的平均潜在土壤侵蚀为84 415.7 t/(km^(2)·a),平均实际土壤侵蚀为210.25 t/(km^(2)·a)。小流域的实际土壤侵蚀主要分布于0~300 t/(km^(2)·a),小流域尺度上潜在土壤侵蚀与实际土壤侵蚀空间分布格局基本一致,高值区主要分布于研究区中部与东部海拔较高的山区腹地;2)植被覆盖度、坡度分别为小流域尺度上潜在土壤侵蚀与实际土壤侵蚀的主要影响因子,植被覆盖度、坡度与土壤侵蚀呈显著正相关(P<0.01)。高植被覆盖区主要分布于林地占比较高的大别山区腹地,坡度较大的区域沿大别山山脊线自西向东分布。3)SOFM结果显示,小流域尺度上的大别山水土保持空间管控区域划分为重点预防区、一般预防区与其他区域,其中重点预防区涉及小流域710个,面积15 287.4 km^(2)。一般预防区共890个小流域,面积18 874.4 km^(2)。两个预防区面积共占研究区61.2%。各区域间的实际土壤侵蚀、潜在土壤侵蚀与坡度差异明显,可作为大别山水土保持空间管控各区域的主要划分指标。研究结果为水土保持空间管控分区提供了思路,为分区域进行水土保持空间管控提供了理论支持与决策依据。

沿黄丘陵沟壑区水土保持生态空间分布特征及时空演化——以山西省柳林县为例

黄河中游是黄土高原地区土壤侵蚀的核心区域,水土流失问题严重,加强中游水土保持工作对于推动黄河流域生态保护和实现高质量发展至关重要。本文选择沿黄河中游丘陵沟壑区典型县域——山西省柳林县为研究区,基于水源涵养空间、土壤保持空间及水土流失敏感性识别和分级,对水土保持生态空间进行划定分区,并采用冷热点分析、标准差椭圆的方法揭示研究区水土保持生态空间的分布特征,并分析其2000—2020年时空演化特征。结果表明:1)柳林县水源涵养空间的功能等级总体呈由北向南逐渐降低的趋势,高等级面积占研究区总面积的35.2%;土壤保持强度以低等级为主,集中分布在研究区的西部及中部。2)2000—2020年柳林县水土流失高度敏感区占比一直在40%以上且面积持续增加,不敏感区、轻度敏感区及中度敏感区面积持续减少。3)柳林县水土保持生态空间分布整体呈南—北走向,无成片连续分布,主要集中在丘陵沟壑区的沟间区域,其中重点区与核心区交错分布在沟道陡坡区,一般区主要分布在河流或沟道沿岸坡度较缓的区域。4)2000—2020年,核心区面积一直呈减小趋势,一般区、重点区及核心区的标准差椭圆重心均向西南方向移动,以向南移动为主。柳林县的水土保持生态空间识别与时空演变趋势研究结果可为其水土保持的差别化治理提供参考,有效保持水土资源,推动黄河流域生态保护与高质量发展。

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。

平原水网地区开发区水土保持评估报告编制探讨

探讨平原水网地区开发区水土保持区域评估报告编制的重点内容和存在的难点,并结合已批复的开发区水土保持区域评估报告,分析评估报告编制应注意的方面:①开发区水土保持评估报告编制大纲应参照国标并可做章节简化,体现整体性、全局性和指导性;②水土流失防治目标要结合个性指标并相应提出区域性控制指标;③土石方量可参考区内典型已验收生产建设项目的土石方挖填模数进行计算,土石方平衡遵循表土应剥尽剥,区内综合利用的原则;④要突出开发区水土保持总体布局和防治体系的完整性,明确单个防治分区的防治措施体系、防治标准和任务;⑤开发区管理机构应有明确的职责,实施负面清单制度。

城市平原区水土保持监测内容与指标研究

以北京市为例,通过研究北京市城市平原区水土保持功能定位和水土流失特征,结合海绵城市建设要求,试探性地提出了以城市水土保持、河岸带水土保持、农村水土保持、施工临时水土保持4类措施为主要监测内容,径流量、泥沙含量、植被覆盖率、COD、SS、氨氮共6项监测指标的城市平原区水土保持监测指标体系。该体系还属于探索阶段,需不断优化完善,以期为全国城市平原区水土保持监测提供借鉴。

辽西低山丘陵区坡面暴雨产流产沙过程及水保效益

基于辽西低山丘陵区二道岭小流域坡面径流和泥沙现场观测,研究暴雨条件下(7·28暴雨)6种不同水土保持措施的坡面产流产沙过程及水土保持效益。结果表明,在暴雨过程中,与裸地相比,耕作措施中的顺垄耕作缩短了初始产流时间,工程措施和林草措施延长了初始产流时间。不同措施的产流产沙过程和雨强变化趋势相似,横垄耕作的径流和含沙量与雨强存在延后现象。在暴雨条件下,以裸地作为对照,林草措施具有良好的减流减沙效果,而农业措施的顺垄耕作则增大了产流产沙作用,加剧了水土流失。

坝上地区典型防护林水源涵养功能对林分结构的响应

【目的】坝上是京津冀地区重要的生态屏障和水源涵养地,探究典型防护林林分结构对枯落物层和土壤层水源涵养功能的影响,为该地区防护林的抚育管理与林分优化提供科学依据。【方法】选取坝上地区御道口林场3种典型防护林(樟子松林、华北落叶松林、樟子松华北落叶松混交林)为研究对象,调查胸径、树高、林龄、密度、郁闭度和叶面积指数等林分结构指标,通过室内浸水法和环刀法进行枯落物层和土壤层持水性能的测定,运用冗余分析探究防护林结构对枯落物层和土壤层持水性能的影响机制。【结果】(1)樟子松华北落叶松混交林的枯落物层厚度、蓄积量、枯落物最大持水量和有效拦蓄量均大于纯林,其中总枯落物厚度差异显著(P<0.05)。(2)土壤总孔隙度、含水量和最大持水量都随着土层的增加而减小。其中土壤总孔隙度和最大持水量在0~30 cm土层表现为华北落叶松林>樟子松华北落叶松混交林>樟子松林,在30~60 cm土层表现为华北落叶松林>樟子松林>樟子松华北落叶松混交林。(3)冗余分析表明,林分结构与水源涵养功能密切相关,林分密度和树高对不同防护林枯落物层水源涵养能力影响显著,而树高和林龄对不同防护林土壤层水源涵养能力影响显著(P<0.05)。【结论】3种防护林中枯落物层和土壤层水源涵养能力最好的分别是樟子松华北落叶松混交林和华北落叶松林,林分密度、树高和林龄可以较好地解释水源涵养功能的变化。本研究对坝上地区生态平衡维护与可持续发展具有积极意义。

陕西省水土保持率远期目标值与分阶段目标值的确定与探讨

[目的]探讨和明确陕西省水土保持率远期目标值与分阶段目标值,为准确评价该区水土保持工作成效和科学推进水土流失综合防治工作提供科学支撑。[方法]综合考虑陕西省社会经济条件与自然条件,分析对应年度水土流失面积变化情况及水土保持率变化情况,结合各年度水利年鉴和全国水土保持规划实施情况考核评估结果,结合土壤侵蚀分类分级、土地利用、海拔地形、植被覆盖、地理空间数据,研判现状条件下陕西省水土流失治理形势,确定陕西省2050年水土保持率远期目标值,及2025,2030和2035年分阶段目标值,并结合目标责任考核,提出陕西省水土保持率的实现途径。[结果]①自2011年以来陕西省水土流失面积年均减少量不断降低,治理难度不断加大,陕西省水土流失面积由72686.00 km^(2)降低至2022年的62637.02 km^(2);②至2050年,水土流失治理措施全部实施后,预计削减水土流失面积21607.05 km^(2),水土保持率远期目标值为79.02%;③2025,2030和2035年分阶段目标值分别为71.42%,73.97%和75.62%。[结论]科学合理地确定陕西省水土保持率目标值,可以满足陕西省落实生态文明建设目标评价考核与水土保持目标责任考核等工作的需求。

岩溶库区不同植被类型土壤碳、氮及其组分特征-以贵阳市花溪水库为例

在贵阳市花溪水库附近选择3种植被类型(草地、灌丛、竹林)作为研究对象,探究3种植被类型下不同土层中土壤碳、氮含量及其不同活性组分的特征。结果表明:植被对碳、氮及其组分(除铵态氮外)影响显著,随植被类型变化(草地→灌丛→竹林)有机碳及其各活性组分含量逐渐增加,A层>B层;竹林中有机碳含量为36.16 g·kg^(-1)、29.68 g·kg^(-1),明显高于草地中的20.48 g·kg^(-1)、18.24 g·kg^(-1);草地中微生物碳含量仅占竹林的54%及49%,水溶性碳在有机碳中的比例最小(0.04%~0.11%),其次是微生物量碳;微生物量氮所占比例最少,仅占全氮中的0.02%~0.20%,随植被变化(草地→灌丛→竹林)微生物量氮含量逐渐增加,硝态氮含量逐渐降低,铵态氮的含量远高于硝态氮的含量,微生物量氮与碱解氮的含量随土层加深含量降低,全氮含量增加。土壤的C/N在8.49~21.52之间,在A层中表现为草地<灌丛<竹林,A层>B层。因此,植被类型对岩溶地区的土壤质量及附近水域均会产生影响,在岩溶水源涵养区,竹林及灌丛更有利于保持水土及附近水域的水质,草地不适合作为岩溶地区生态修复的植被类型。

西气东输三线七标段项目秦岭段生态环境保护实践

西气东输三线七标段项目穿越秦岭环境敏感区,该区域生物多样性丰富,植被覆盖率高,是重要的水源地,因此对项目施工作业过程中环境保护的要求非常高。文章根据项目施工作业特点和周边环境情况,从专项方案制定、防止水土流失、防止水污染、防止设备设施污染、防止有毒有害固体废物污染等方面着手,提出了切实可行的保护生态环境的组织、管理、技术手段。在最大程度上减少了项目施工作业对周边环境的影响,使项目绿色环保工作平稳有序进行。同时分析了当前工作存在的不足,指出下一步在施工方案优化、植被恢复、节能减排、技术创新、宣传培训等方面需要加强。