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养分回收加剧了氮沉降背景下盐渍化草地优势植物内在氮磷的失衡

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Journal of Plant Ecology 2024年第1期17卷 111-120页

作者： Yuan Su Shuaikai Wu Jie Hao Huajie Diao Kuanhu Dong changhui wang Shanxi Key Laboratory of Grassland Ecological Protection and Native Grass Germplasm Innovation College of Grassland ScienceShanxi Agricultural UniversityTaigu 030801China Youyu Loess Plateau Grassland Ecosystem National Research Station Shanxi Agricultural UniversityTaigu 030801China

在落叶之前,从衰老组织中重新吸收养分被认为是植物适应养分缺乏的一种策略。然而,养分重吸收如何调节植物体内氮(N)和磷(P)的平衡仍不清楚,特别是在土壤氮有效性增加的情况下。本文研究了不同速率(0、1、2、4、8、16、24和32 g N m^(-2... 详细信息

在落叶之前,从衰老组织中重新吸收养分被认为是植物适应养分缺乏的一种策略。然而,养分重吸收如何调节植物体内氮(N)和磷(P)的平衡仍不清楚,特别是在土壤氮有效性增加的情况下。本文研究了不同速率(0、1、2、4、8、16、24和32 g N m^(-2)yr^(-1))氮添加对中国北方盐渍化草地优势植物赖草(Leymus secalinus)叶片和茎秆养分回收的影响,以及养分回收在调控植物内部氮磷平衡的作用。研究结果表明:氮添加6年后,随着施氮量的增加,绿色和衰老组织(叶和茎)的N浓度和氮磷比均呈上升趋势。随着施氮量的增加,绿色组织中P浓度降低,而衰老组织中P浓度无显著变化。N重吸收效率(NRE)、P重吸收效率(PRE)和NRE:PRE比值沿N添加梯度显著降低。此外,我们发现衰老组织(叶和茎)氮磷比比绿色组织(叶和茎)氮磷比对氮素添加的响应更敏感,植物内在氮磷失衡的加剧主要是由于不成比例的减少养分重吸收,尤其是NRE。总的来说,我们的研究表明,NRE和PRE的差异进一步加剧了植物凋落物内部氮磷的失衡。

关键词：生态化学计量学氮添加氮磷失衡重吸收效率重吸收能力重吸收比盐渍化草地

尿酸/高密度脂蛋白胆固醇比值与房颤射频消融术后复发的相关性

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安徽医科大学学报 2024年第7期59卷 1269-1274页

作者：王保龙王昌会安徽医科大学第一附属医院心血管内科合肥230022

目的探讨尿酸/高密度脂蛋白胆固醇比值(UHR)与非瓣膜性房颤患者射频消融术后晚期复发的相关性。方法选取2018年1月—2022年1月首次接受经导管心脏射频消融治疗的586例非瓣膜性房颤患者的临床资料,根据UHR值三分位法,把研究人群分为低值... 详细信息

目的探讨尿酸/高密度脂蛋白胆固醇比值(UHR)与非瓣膜性房颤患者射频消融术后晚期复发的相关性。方法选取2018年1月—2022年1月首次接受经导管心脏射频消融治疗的586例非瓣膜性房颤患者的临床资料,根据UHR值三分位法,把研究人群分为低值组(n=196)、中值组(n=195)和高值组(n=195),房颤晚期复发为随访终点事件。比较三组间一般资料和实验室检查指标,采用Kaplan-Meier法估计并绘制生存曲线,采用多因素COX回归分析评价UHR与消融术后房颤复发的独立相关性并进行亚组分析。结果随访时间内共记录了182例(31.1%)房颤患者的晚期复发。Kaplan-Meier生存曲线显示UHR低值组、中值组、高值组三组间窦性心律维持率逐渐降低(Log-rank检验,P<0.001)。在完全校正模型中,与低值组的患者比较,中值组和高值组消融术后房颤晚期复发的HR(95%CI,P)分别为1.56(0.99~2.42,P=0.057)和2.03(1.28~3.23,P=0.003)。亚组分析显示,在年龄≥60岁、体质量指数≥25 kg/m^(2)、持续性房颤、左心房内径≥4.3 cm、高血压病、无心力衰竭及无高脂血症的患者中,观察到UHR与消融术后房颤晚期复发的相关性显著。结论非瓣膜性房颤患者较高的UHR值与射频消融术后房颤晚期复发风险增加独立相关。

关键词：尿酸高密度脂蛋白胆固醇心房颤动射频消融术晚期复发

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“非课堂”:一种学生立场的职业教育教学新样态

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中国职业技术教育 2024年第11期 33-40,48页

作者：张国红李双彤王长辉金华市教育教学研究中心职教部浙江省兰溪市职业中等专业学校浙江省兰溪市教育局教研室

针对职业学校中普遍存在的学生学习投入度不足与教学效率偏低的问题,创新性地提出了一种全新的教学样态——“非课堂”。这一概念实现了从传统的时空视角到学生视角的根本转变,旨在为学生营造一种“无课堂感”的自然学习情境,从而激发... 详细信息

针对职业学校中普遍存在的学生学习投入度不足与教学效率偏低的问题,创新性地提出了一种全新的教学样态——“非课堂”。这一概念实现了从传统的时空视角到学生视角的根本转变,旨在为学生营造一种“无课堂感”的自然学习情境,从而激发其学习热情与主动性。在实施策略上,坚持自然性、真实性与情境性的原则,通过教学内容的项目化、教学方法的自然序、教学平台的支持性以及教学空间的场域化等四个维度的整体构建,为非课堂的实施提供有力的支撑。借助现代技术手段使得“非课堂”教学得以多维度协同进化和整体性优化。“非课堂”概念的提出对加速职业教育的自我革新有着重要意义,对整个教育体系改革具有普适性价值。

关键词：职业教育教学非课堂学生立场自然性

Comparison of different phosphate species adsorption by ferric and alum water treatment residuals

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Journal of Environmental Sciences 2013年第5期25卷 986-992页

作者： Sijia Gao changhui wang Yuansheng Pei The Key Laboratory of Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal University

As safe byproducts of drinking water treatment processes,ferric and alum water treatment residuals（FARs） have the potential to be new phosphate（P） immobilization *** this study,batch experiments were conducted to investigate and compare the adsorption characteristics of three P species by *** results showed that the kinetic processes of different P species＇ adsorption by FARs could be described by a pseudo second-order *** ranking list of the initial adsorption rates with respect to different phosphates was pyrophosphate,phytate,orthophosphate,hexametaphosphate and *** the six models considered,the two-site Langmuir model most effectively described the adsorption characteristics of the various P *** fitting the results,the maximum adsorption capacities were determined to be 40.24 mg/g for phytate,18.04 mg/g for pyrophosphate,17.14 mg/g for orthophosphate,15.86 mg/g for hexametaphosphate and 10.81 mg/g for *** addition,the adsorption processes of the different P species were spontaneous endothermic processes and were favored at lower pH *** pH dependency was found to be especially true for orthophosphate,where the adsorption capacity decreased by 1.22 mg/g with an increase in pH from 5 to *** of the adsorbed P species from the FARs demonstrated that Al-P and Fe-P were the dominating forms,constituting approximately 80%-90% of the total P fractions,which indicated that the adsorbed P species had a low leaching risk and could stably exist in the ***,the FARs could be effective in controlling pollution in water caused by different P species.

关键词： ferric and alum water treatment residuals different phosphate species adsorption phosphate fractions

Investigation on the eco-toxicity of lake sediments with the addition of drinking water treatment residuals

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Journal of Environmental Sciences 2016年第8期28卷 5-15页

作者： Nannan Yuan changhui wang Yuansheng Pei The Key Laboratory of Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

Drinking water treatment residuals（WTRs） have a potential to realize eutrophication control objectives by reducing the internal phosphorus（P） load of lake sediments. Information regarding the ecological risk of dewatered WTR reuse in aquatic environments is generally lacking, however. In this study, we analyzed the eco-toxicity of leachates from sediments with or without dewatered WTRs toward algae Chlorella vulgaris via algal growth inhibition testing with algal cell density, chlorophyll content, malondialdehyde content, antioxidant enzyme superoxide dismutase activity, and subcellular structure indices. The results suggested that leachates from sediments unanimously inhibited algal growth, with or without the addition of different WTR doses（10% or 50% of the sediment in dry weight） at different p H values（8–9）, as well as from sediments treated for different durations（10 or 180 days）. The inhibition was primarily the result of P deficiency in the leachates owing to WTR P adsorption, however, our results suggest that the dewatered WTRs were considered as a favorable potential material for internal P loading control in lake restoration projects, as it shows acceptably low risk toward aquatic plants.

关键词： Drinking water treatment residuals Lake restoration Sediment Eco-toxicity Algae

“高碳高湿”煤气化细渣特性分析及干燥动力学研究

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中国矿业 2024年第9期33卷 204-211页

作者：王常辉王奕博张瀚霖李睿张伊黎于伟中核华辰建筑工程有限公司陕西西安712000 西安交通大学能源与动力工程学院陕西西安710049

“高碳高湿”煤气化细渣固定碳含量高、干基高位发热量高,但由于其水分高达70%左右,导致收到基低位发热量低,严重影响其进一步综合利用。宁夏水煤浆炉气化细渣样品灰分为50.04%,干基高位发热量达到3809 cal/g,具有较高利用价值,但该煤... 详细信息

“高碳高湿”煤气化细渣固定碳含量高、干基高位发热量高,但由于其水分高达70%左右,导致收到基低位发热量低,严重影响其进一步综合利用。宁夏水煤浆炉气化细渣样品灰分为50.04%,干基高位发热量达到3809 cal/g,具有较高利用价值,但该煤气化细渣滤饼水分高达69.2%,收到基低位发热量仅为790 cal/g,进一步降低滤饼水分,是有效提高其综合利用效率的关键。该细渣含有SiO_(2)、Fe_(2)O_(3)、CaSi_(2)等矿物,微观形貌主要由絮状结构、独立球状颗粒、絮状球状混杂结构组成,且絮状结构表面的元素主要为C和O,球状颗粒表面的元素主要为O、C和Fe,同时,形貌观察可知该煤气化细渣孔隙发达,脱水困难。对细渣滤饼样品进行干燥脱水实验,在不同的干燥温度下,干燥速率呈现先增大后逐渐减小的变化规律。干燥动力学模型中,半经验模型相较于半理论模型更能准确描述该煤气化细渣的干燥脱水特性,其中,Page模型拟合效果最为突出,且形式最为简单,拟合得到干燥脱水的动力学方程。

关键词：煤气化细渣脱水微观形貌干燥速率动力学模型

Influence of the inherent properties of drinking water treatment residuals on their phosphorus adsorption capacities

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Journal of Environmental Sciences 2014年第12期26卷 2397-2405页

作者： Leilei Bai changhui wang Liansheng He Yuansheng Pei The Key Laboratory of Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University Water Environment System Project Laboratory Chinese Research Academy of Environmental Sciences

Batch experiments were conducted to investigate the phosphorus（P） adsorption and desorption on five drinking water treatment residuals（WTRs） collected from different regions in China. The physical and chemical characteristics of the five WTRs were determined. Combined with rotated principal component analysis, multiple regression analysis was used to analyze the relationship between the inherent properties of the WTRs and their P adsorption capacities. The results showed that the maximum P adsorption capacities of the five WTRs calculated using the Langmuir isotherm ranged from 4.17 to8.20 mg/g at a p H of 7 and further increased with a decrease in p H. The statistical analysis revealed that a factor related to Al and 200 mmol/L oxalate-extractable Al（Alox） accounted for 36.5% of the variations in the P adsorption. A similar portion（28.5%） was attributed to an integrated factor related to the p H, Fe, 200 mmol/L oxalate-extractable Fe（Feox）, surface area and organic matter（OM） of the WTRs. However, factors related to other properties（Ca,P and 5 mmol/L oxalate-extractable Fe and Al） were rejected. In addition, the quantity of P desorption was limited and had a significant negative correlation with the（Feox＋ Alox） of the WTRs（p 〈 0.05）. Overall, WTRs with high contents of Alox, Feoxand OM as well as large surface areas were proposed to be the best choice for P adsorption in practical applications.

关键词： Adsorption Desorption Drinking water treatment residuals Phosphorus Principal component analysis

Use of Fe/Al drinking water treatment residuals as amendments for enhancing the retention capacity of glyphosate in agricultural soils

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Journal of Environmental Sciences 2015年第8期27卷 133-142页

作者： Yuanyuan Zhao Laura A.Wendling changhui wang Yuansheng Pei The Key Laboratory of Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University School of Agriculture and Food Sciences University of Queensland State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

Fe/Al drinking water treatment residuals（WTRs）, ubiquitous and non-hazardous by-products of drinking water purification, are cost-effective adsorbents for glyphosate. Given that repeated glyphosate applications could significantly decrease glyphosate retention by soils and that the adsorbed glyphosate is potentially mobile, high sorption capacity and stability of glyphosate in agricultural soils are needed to prevent pollution of water by ***, we investigated the feasibility of reusing Fe/Al WTR as a soil amendment to enhance the retention capacity of glyphosate in two agricultural soils. The results of batch experiments showed that the Fe/Al WTR amendment significantly enhanced the glyphosate sorption capacity of both soils（p 〈 0.001）. Up to 30% of the previously adsorbed glyphosate desorbed from the non-amended soils, and the Fe/Al WTR amendment effectively decreased the proportion of glyphosate desorbed. Fractionation analyses further demonstrated that glyphosate adsorbed to non-amended soils was primarily retained in the readily labile fraction（Na HCO3-glyphosate）. The WTR amendment significantly increased the relative proportion of the moderately labile fraction（HCl-glyphosate） and concomitantly reduced that of the Na HCO3-glyphosate, hence reducing the potential for the release of soil-adsorbed glyphosate into the aqueous phase. Furthermore, Fe/Al WTR amendment minimized the inhibitory effect of increasing solution p H on glyphosate sorption by soils and mitigated the effects of increasing solution ionic strength. The present results indicate that Fe/Al WTR is suitable for use as a soil amendment to prevent glyphosate pollution of aquatic ecosystems by enhancing the glyphosate retention capacity in soils.

关键词： Glyphosate Soil amendment Fe/Al drinking water treatment residuals Sorption capacity Stability

Effects of nitrogen addition and mowing on nitrogen-and water-use efficiency oi Artemisia frigida in a grassland restored from an abandoned cropland

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Journal of Plant Ecology 2021年第3期14卷 515-526页

作者： Huajie Diao Paul Kardol Kuanhu Dong changhui wang College of Grassland Science Shanxi Agricultural UniversityTaigu 030801China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Youyu Loess Plateau Grassland Ecosystem Research Station Shanxi Agricultural UniversityTaigu 030801China Department of Forest Ecology and Management Swedish University of Agricultural Sciences901-83 UmcaSweden

Aims Competition among plants in a community usually depends on their nitrogen(N)-use efficiency(NUE)and water-use efficiency(WUE)in arid and semi-arid *** frigida is an indicator species in heavily degraded grassland,however,how its NUE and WUE respond to N addition in different successional stages is still unclear,especially with mowing,a common management practice in semi-arid *** Based on a long-term controlled experiment with N addition and mowing in an abandoned cropland from 2006 to 2013,we investigated the NUE and WUE oi *** in two patches(*** and herb patches)in 2013 which represented two potential successional stages from herb to grass *** coverage of *** was higher(about 50%)in the herb patch than in the grass patch(about 10%).Stable isotopic C(δ^(13)C)and N(δ^(15)N)as well as C and N pools were measured in plants and *** was calculated as leaf C/N,and leafδ^(13)C values were used as a proxy for *** Findings N addition did not affect WUE of ***,but significantly decreased NUE by 42.9%and 26.6%in grass and herb patches,*** response of NUE to N addition was related to altering utilization of different N sources(NH_(4)^(+)***_(3)^(-))by *** according to the changed relationship between leafδ^(15)N/soil 615N and *** had no effect on NUE regardless of N addition,but significantly increased WUE by 2.3%for *** without N addition in the grass *** addition of N reduced the positive effect of mowing on its WUE in grass *** results suggested that decreased NUE and/or WUE of *** under mowing and N addition could reduce its competition,and further accelerate restoration succession from the abandoned cropland to natural grassland in the semi-arid region.

关键词： mowing nitrogen addition nitrogen-use efficiency semi-arid grassland water-use efficiency