Engineering Study on the Treatment of Multi-soil-layering System on the Rural Domestic Wastewater in Taihu Basin

By combining with the actual situation in the rural area,the practical technology of domestic wastewater treatment which had the wide popularization value was developed in the rural area of Taihu Basin.Moreover,the multi-soil-layering system was used to treat the concentrated rural domestic wastewater,and the demonstration project was established in Fenshui Village,Yixing,Jiangsu.The result showed that the infrastructure and operating cost of system was low,and the treatment effect was good.The average removal ratios of COD,NH+4-N,TN,TP and SS were respectively 70%,83%,59%,76% and 94%.The quality of yielding water could reach Grade A standard of Pollutant Emission Standards in Urban Wastewater Treatment Plant.

Dynamic Mechanisms for Evolution of Mountain Rural Settlements and Soil Conservation in Upper Yangtze River Basin

This paper presents the logic relationship between rural settlement reconstruction and soil conservation in the Upper Yangtze River. Firstly, by introducing the concepts of ＂flow＂ and ＂intercepted flow＂, we probe into the dynamic mechanism on interaction between ecological and environmental system, and then point out that the ＂intercepting sites＂ are physical conditions for establishment of human settlements in mountains. Secondly, by using ecological theories, ＂flow＂, ＂source＂, and ＂sink＂, material cycle and energy flow in mountains have been discussed. Thirdly, according to dissipative structure theory and thermodynamic laws, a hypothesis has been proposed that ＂entropy flow＂ is a dynamic force for settlement evolution. Finally, it is argued that a project for soil conservation is set to control and utilize flows so rural settlements can be supported and farmers＇ life improved.

Evaluation on Heavy Metal Content in Soil of Rural Landfill in Chongqing

To understand heavy metal content in soil of rural landfill in Chongqing, samples were collected at 10 sampling sites of different counties. Zn, Cr, Cu, Cd and Pb contents were analyzed, and their pollution degrees were evaluated by single-factor evaluation and index of geoaccumulation. Results displayed that there was no Cr pollution in soil of rural landfill in Chongqing, but Cd pollution was very serious. Pb, Zn and Cu showed spatial difference in different counties. Dispersion degrees of Zn and Pb pollution were lower, and their pollution degrees were also relatively lower. Dispersion degree of Cu pollution was higher, and its pollution degree was also relatively higher.

Soil quality and sustainable land use in urban-rural marginal area: a case study of Kaifeng

By using the basic theories of physical geography, land resources and ecology, this article analyzes the soil quality of the rural-urban marginal area in Kaifeng. Computer techniques, based on soil samples analysis, are used to study soil quality changes in the Kaifeng’s rural-urban marginal area. While focusing on nutrient circle key links of input and output in soil, relying on numerous practical survey data, this article reveals clearly the impact of land use change on soil quality.

Effects of land use change on the spatiotemporal variability of soil organic carbon in an urban-rural ecotone of Beijing,China

Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon （SOC） can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District -- an urban-rural ecotone of Beijing, China, the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed. Results showed that from 1982 to 2009 in Pinggu District, the following land use change mainly occurred： Grain cropland converted to orchard or vegetable land, and grassland converted to forestland. The SOC content decreased in region where the land use type changed to grain cropland （e.g., vegetable land to grain cropland decreased by 0.7 g kg-1; orchard to grain cropland decreased by 0.2 g kg-l）. In contrast, the SOC content increased in region where the land use type changed to either orchard （excluding forestland） or forestland （e.g., grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1, respectively; grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1, respectively）. The organic carbon accumulation capacity per unit mass of the soil increased in the following order： grain cropland soil〈vegetable land/grassland soil〈orchard soil〈forestland soil. Therefore, to both secure supply of agricultural products and develop low carbon agriculture in a modern city, orchard has proven to be a good choice for land using.

Impact of Soil Erosion on Rural Poverty

This article gives an overview of the general situation and regional differences of rural poverty in China, and points out that in the rural areas of central and western regions with serious soil erosion, the poverty is particularly prominent. Based on previous studies, we take agricultural GDP as the dependent variable, farmland area, agricultural labor, agricultural capital stock, irrigation area, and consumption of chemical fertilizer as the independent variables, to establish the C-D production function reflecting impact of soil erosion on rural poverty for regression analysis. The results show that farmland, labor, capital, irrigation, chemical fertilizer and other production factors have a positive effect on agricultural GDP; soil erosion has a significant negative effect on agricultural production; in western China, the total factor productivity is the lowest and soil erosion is the most serious. In order to resolve the dilemma of soil erosion and rural poverty, it is necessary to change the extensive mode of agricultural development, protect the ecological environment, and take the road of intensive development of agroecology.

Contribution of Asian dust to soils in Southeast China estimated with Nd and Pb isotopic compositions

Asian dust has been identified in subtropical soils of China.Neodymium(Nd)and lead(Pb)elemental and isotopic geochemistry of soils in Southeast China were used to assess the significance of local versus extraneous sources.The εNd(0)values were close to the parent rocks(+2.9)in the young soils(NSJ);while their values were always negative(〜—3.7)in the old soils(OMJ),implying dust deposition.The young soils contained less Asian dust contribution(<8%)while the old soils contained more than 50%Asian dust contribution.This implied that dust contributions were gradually increasing with the soil development stage and Asian dust input had become the principal Nd source for the old soils in this area.On the other hand,Pb excesses and low 207Pb/206Pb values(〜0.8503)in near-surface soils indicated a significant anthropogenic Pb addition onto surface soils.The close relationship between the Pb content and isotopic ratios in the soil profile indicated that the excessive lead in the surface soil was exogenous.These results suggested that Asian dust made up a significant fraction in the old soils,but that local sources(i.e.,basalt and anthropogenic)were not trivial in Southeast China.

涉农高校助推土壤保护工作路径新探究——以扬州大学土壤医院为例

乡村振兴战略是新发展阶段实现我国农业农村现代化的重大决策部署。虽然乡村振兴已经取得明显成效,但仍有一些方面的问题有待创新性解决。由于人为管理土壤肥力方式不当,导致次生盐渍化、土壤酸化、连作障碍等退化问题频发,给耕地土壤质量、农产品安全与质量保障造成严重威胁。但土壤问题综合性强、复杂多样,农民、农技人员专业素质不够、土壤修复成本过高,很大程度上限制着耕地保护计划实施。土壤医院以高校师生团队为平台,对障碍土壤开展调查与采样分析,综合立定土壤地力质量等级,确定土壤地力质量定量提升方法,结合目标作物产量推荐土壤-作物养分管理实施方案,并开展实验室模拟试验、校验和田间试验示范。该模式将农教学、产学研深度结合,把知识播撒在大地,把技术教给农民,可有效地促进各地农民增收、乡村振兴,值得涉农高校在全国范围内推广、应用。

Rural Idyll in Vernacular Landscape

The so-called “rural idyll” is considered the most poetic part of the traditional vernacular landscape.Although mostly appreciated by men of letters in their writings,rural idyll is a love song deeply rooted in local soil.It is local soil that is the ultimate producer of rural idyll.For a rural society,rural idyll also seems to be associated with “primitive.” There are significant cognitive differences in this regard between China and the West.Traditional Chinese rural society,full of soil fragrance and vitality,interacts with life and seasons to compose a harmonious man-earth symphony.

东北黑土区农村宅基地功能转型特征与机制研究——以海伦市长华村为例

研究目的:揭示东北黑土区村域尺度农村宅基地功能转型特征与驱动机制,探寻“三权分置”制度框架下宅基地的活化利用与有效管理对策。研究方法:实地调查法和案例研究法。研究结果:(1)东北黑土区内农村宅基地的居住功能弱化,农业生产功能增强,宅基地功能由居住功能主导向居住、生产二元复合功能或农业生产功能为主导转变;(2)村域尺度内,农村宅基地功能转型的阶段特征明显,空间上表现为与中心村的距离越远,宅基地功能转型程度越剧烈;(3)在城镇化等外缘要素的影响下,乡村地域系统内人口和产业的变化共同驱动农村宅基地功能转型;(4)农村宅基地“三权分置”的制度框架下,结合农村宅基地功能组合和利用状态,引导农户选择适宜的宅基地利用方式,有利于促进宅基地利用效率提升。研究结论:东北黑土区农村宅基地功能正在经历转型过程,应根据宅基地功能转型阶段特征,深化农村宅基地“三权分置”改革,筛选适宜的宅基地利用与管理方式。

乡村水泥路面拼接窄长加宽板受力特性分析

福建省农村公路水泥路面多为4.5m×5m的单板单车道,随着交通量的增加,多加宽2m成为双车道。建立有限元模型,研究新旧板缝间摩擦系数、拉杆间距、土基模量等参数下水泥板加宽2m前后的受力变化,发现新旧路基模量差对板底拉应力影响最大,拉杆间距影响不大,但对板缝两侧弯沉差影响最大。

农村土壤污染修复基金机制建构研究

在经济高速发展背景下,生态环境问题不断涌现,其中农村土壤污染问题在“三农”发展中亟须解决。在概述农村土壤污染类型的基础上,结合美国、日本这两个国家的土壤污染社会化救济经验,提出了我国农村土壤污染修复基金建构路径,为农村地区长久发展提供制度建设,实现乡村振兴伟大战略。

Persistence of Dioxin TCDD in Southern Vietnam Soil and Water Environments and Maternal Exposure Pathways with Potential Consequences on Congenital Heart Disease Prevalence in Vietnam

Waterlogged soils and submerged sediments in wetlands and agricultural lands used for rice paddies and aquaculture have anaerobic conditions that slow and prevent the photo and microbial degradation of dioxin TCDD (2,3,7,8-tetracholorodibenzo-p-dioxin), enabling it to persist in environments for long periods. Over 1.6 million ha of land in southern Vietnam were sprayed with 2,4,5-T herbicides (e.g. Agent Orange) contaminated with dioxin TCDD during the Vietnam War (1961-1971);45% of these ha received four or more spray flight missions. Dioxins are endocrine disrupters and may induce cardiovascular disease, growth, and developmental defects, diabetes, hormonal dysfunctions and disruptions, certain cancers, and chloracne. Outpatient screening clinic 2020 data on Vietnamese children suspected of congenital heart disease (CHD) showed the childhood CHD prevalence rate in Vietnam of 13.356/1000, significantly elevated compared to the Asian CHD prevalence rate of 3.531/1000. CHD prevalence rate differences between North Vietnam (2.541/1000) and south of the 17th parallel (10.809/1000) were significant. Vietnamese farmers, especially pregnant women whose occupations involve daily contact with soil and sediments where dioxin TCDD persists in the environment may be at risk of dioxin accumulation from dermal exposure and bioaccumulation via diet. There is an urgent need for funded longitudinal genetic and clinical studies to assess CHD and other organ system childhood malformations due to in utero TCDD exposure. We recommend an integrated research design involving 1) site-specific locations that received high volumes and multiple spray loads of herbicides during the Vietnam War;2) soil sampling of submerged and waterlogged soils and sediments where TCDD may not have degraded;3) production areas of agriculture, fisheries, and other aquatic products;4) risk assessment dioxin levels in foods where TCDD is likely to bioaccumulate;5) child-bearing age and pregnant women with potentially high sensitivity to long-term low dose exposure, and 6) men and women in occupations that are in daily contact with contaminated soil and sediments as part of their job routines.

城乡梯度3种林分类型土壤酶活性及影响因素

以广州市城区、近郊和乡村森林土壤为研究对象,探讨马尾松林、针阔混交林和常绿阔叶林土壤酶活性特征及其与理化性质和重金属之间的关系。结果表明:马尾松林土壤酸性磷酸酶(AP)、脲酶(URE)活性以及针阔混交林土壤过氧化氢酶(CAT)、URE、脱氢酶(DH)活性均为近郊>乡村>城区,而常绿阔叶林土壤AP、URE、DH活性为近郊>城区>乡村。城区、近郊针阔混交林土壤pH值、砂粒含量均显著高于马尾松林和常绿阔叶林(P<0.05);土壤有机质(SOM)、总氮(TN)、总磷(TP)含量均为马尾松林<针阔混交林<常绿阔叶林;乡村针阔混交林土壤SOM含量、阳离子交换量(CEC)、黏粒含量、粉粒含量、含水率在3种林分中均最低。城区马尾松林土壤重金属铜(Cu)、锌(Zn)、铅(Pb)含量在3种林分间均最低,而镉(Cd)含量在3种林分间相同;近郊、乡村常绿阔叶林土壤重金属Zn、Pb含量在3种林分中均最高。土壤含水率、SOM含量、pH值、CEC、Cu含量、黏粒含量、TN含量是土壤酶活性的主要影响因子。相关性分析表明,土壤SOM、TN含量与土壤CAT、AP活性呈显著正相关(P<0.05);土壤TP含量与土壤AP、URE活性呈显著正相关(P<0.05);土壤含水率与土壤DH活性呈显著正相关(P<0.05);而土壤Cu含量与URE活性呈显著负相关(P<0.05)。

“双碳”目标及乡村振兴背景下我国耕地土壤固碳减排的实现路径

通过构建新形势下实现耕地土壤固碳减排的理论分析框架,解析了限制我国耕地土壤固碳减排发展的问题,提出了耕地土壤固碳减排的实现路径。新形势下推进耕地土壤固碳减排,必须坚持保障粮食安全的底线,找准“双碳”工作中农业农村的减排固碳定位,重点是降低单位农产品排放强度,提升固碳能力,推动形成低碳绿色的生产生活方式。推进耕地固碳减排的基本方向是:以推进乡村产业振兴和生态振兴为重要实现路径,推动耕地土壤固碳减排与乡村生态低碳产业发展深度融合,以高标准农田建设、黑土地保护、有机质提升等作为质量支撑保障,以有机循环农业、农业废弃物资源化利用等作为低碳产业支撑保障,健全绿色生态补偿和碳排放市场交易,推动耕地土壤碳汇价值实现,实现粮食保供、农业农村固碳减排、耕地资源可持续利用、农民增收等多目标共赢。

2017-2020年抚顺市农村土壤卫生监测结果分析及评价

目的了解2017-2020年抚顺市农村土壤卫生状况,为制定相关政策和评估土壤风险,提供具体的数据。方法监测分析2017年至2020年抚顺市农村土壤卫生的具体数据。随机选择20个监测点进行土壤监测,测定土壤中寄生虫、重金属等相关指标的含量。结果大窝棚村2020年铅含量达到645 mg/kg;中心屯村铅含量达到2035 mg/kg,镉含量达到1.22 mg/kg,其余各项指标均未超标。结论2017-2020年抚顺市农村土壤卫生状况整体良好,但是个别年份个别区域也有超标情况,须持续加强监测,防患于未然。

打造文化兴盛沃土背景下宁夏乡村文化发展路径研究

宁夏回族自治区第十三次党代会提出“打造文化兴盛沃土”的重要部署,乡村成为其中的重中之重,如何激发宁夏乡村文化发展活力,促进宁夏乡村文化更好发展是亟须回答的问题。文章从乡村文化的内涵入手,分析宁夏乡村文化的基本情况,研究宁夏乡村文化发展存在的问题与挑战,提出了具有针对性的对策路径,以期助力宁夏打造文化兴盛沃土,建设新时代文化强区。

农村土地污染及土壤环境保护方式探讨

随着社会经济的发展,人们的生活水平逐渐提高,物质条件越来越丰富,但由于环保意识的缺乏,污染问题日益严峻,再加上我国农村环境相关环保部门治理措施不当,我国农村环境受到了严重影响。农村土地密切关系着人们的生活起居,农村土地污染是政府部门首要治理问题。基于此,调查农村土地污染相关问题,并根据科学手段对土壤保护提出切实可行的保护措施。

通州区马驹桥镇非道路用地条件下农村等外公路提升建设的新思路

随着通州区马驹桥镇社会经济的高速发展,道路交通出行的需求日益增加,然而现有道路不能满足交通需求,亟须对道路交通进行改造升级。论文对通州区马驹桥镇农村等外公路提升建设项目进行详细阐述,通过固化土路面的建设,有效解决了在非道路用地条件下对农村等外公路的提升改造。

新农科背景下土壤肥料学课程教学体系探索与改革

乡村振兴战略的提出对园艺专业的人才培养目标提出更高的要求。在新农科背景下,土壤肥料学课程必须紧紧围绕立德树人的根本任务开展相关教学。该文旨在分析当前该课程存在的问题,并基于OBE教学理念积极对其教学体系进行探索与改革,培养园艺专业学生成为以强农兴农为己任,具有“懂农业、爱农村、爱农民”的“三农”情怀的新时代创新型人才。