冰川冻土, 2022, 44(2): 623-633 doi: 10.7522/j.issn.1000-0240.2022.0064

寒区工程与灾害

冻融循环作用下植被混凝土团聚结构变化对养分固持能力的影响

刘大翔,1,2, 刘德玉1,3, 童标1,3, 杨悦舒,1,3, 丁瑜1,4, 许文年1,4

1.三峡大学 水泥基生态修复技术湖北省工程研究中心,湖北 宜昌 443002

2.中国科学院 山地灾害与地表过程 重点实验室,四川 成都 610041

3.三峡大学 防灾减灾湖北省重点实验室,湖北 宜昌 443002

4.三峡大学 三峡库区地质灾害教育部重点实验室,湖北 宜昌 443002

Effect of aggregate structure change in vegetation concrete on nutrient retention ability under freeze-thaw cycles

LIU Daxiang,1,2, LIU Deyu1,3, TONG Biao1,3, YANG Yueshu,1,3, DING Yu1,4, XU Wennian1,4

1.Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials,China Three Gorges University,Yichang 443002,Hubei,China

2.Key Laboratory of Mountain Hazards and Surface Processes,Chinese Academy of Sciences,Chengdu 610041,China

3.Key Laboratory of Disaster Prevention and Mitigation of Hubei Province,China Three Gorges University,Yichang 443002,Hubei,China

4.Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education,China Three Gorges University,Yichang 443002,Hubei,China

通讯作者: 杨悦舒,副教授,主要从事边坡生态修复工程评价与调控研究. E-mail: michael_lewandowski@foxmail.com

收稿日期: 2021-01-11   修回日期: 2022-04-08  

基金资助: 国家重点研发计划项目.  2017YFC0504902-02
国家自然科学基金项目.  51708333
湖北省教育厅科学技术研究计划重点项目.  D2022120
长江水利委员会长江科学院开放基金项目.  CKWV2019753/KY
湖北省自然科学基金项目.  2020CFB317
三峡大学研究生学位论文培优基金项目.  2021SSPY018

Received: 2021-01-11   Revised: 2022-04-08  

作者简介 About authors

刘大翔,副教授,主要从事生态护坡基材改良理论与技术研究.E-mail:liudaxiang004@163.com , E-mail:liudaxiang004@163.com

摘要

植被混凝土生态修复技术是当前国内用于裸露陡边坡植被恢复的典型技术之一,具备肥力持续供给能力是植被混凝土有别于其他建筑材料的基本属性。冻融循环作用下物理结构剧变导致养分固持能力减弱是限制植被混凝土在高寒地区应用的关键因素,但养分固持能力变化的深层原因尚不清楚。通过控制性试验,以初始含水率和冻融循环频次为变量,测定了植被混凝土水稳性团聚体粒径分布、团聚特征参数、主要养分含量及其淋溶流失率的变化规律。结果表明:随初始含水率提高,植被混凝土中水稳性微团聚体向大团聚体转化,尤其以≥1~2 mm粒组增幅最多,团聚特征参数变化也反映出团聚体稳定性随之提高;冻融循环导致水稳性团聚体平均粒径不断减小,但会随冻融频次增长逐步趋于稳定。初始含水率的提高促使各养分含量略有增加;冻融循环作用下有机质、铵态氮、有效磷、速效钾含量仍有增长,但硝态氮含量不断降低。同时,冻融循环还会导致各养分淋溶流失率不断增大,最大增幅可超过90%,并随冻融频次增长趋于稳定。这说明冻融循环对养分固持能力的影响会逐步减弱,而且侧面反映出团聚结构与养分固持能力间存在紧密联系。Pearson相关性分析进一步表明,团聚特征参数与各养分淋溶流失率均达到显著相关水平,综合考虑显著性水平与相关性系数绝对值,认为团聚特征参数中几何平均直径与各养分淋失率相关程度最高,最适合用于表征植被混凝土的养分固持能力。上述研究结果证实,冻融循环作用下团聚效应减弱是导致植被混凝土养分固持能力降低的深层原因。

关键词: 冻融循环 ; 植被混凝土 ; 团聚结构 ; 淋溶流失率

Abstract

Vegetation concrete (VC) ecological protection technology is an effective solution for the vegetation recovery of bare steep slopes, which has been increasingly applied in cold regions in recent years. When the technology is implemented, the nutrient retention ability of VC substrate is essentially concerned. Under the actions of freeze-thaw cycles, fertility of the VC substrate as well as natural soil is thought to degrade gradually. It has been recognized that the nutrient retention ability of soil is significantly correlated with its physical structure. Similarly, the nutrient retention ability of VC substrate could be supposed to be physical structure-dependent. To enhance the comprehensive performance of VC substrate in cold regions, the investigation of nutrient retention ability is required, which nevertheless is still little identified. In this study, a series of freeze-thaw cycle experiments for VC substrate were conducted, and the effects of initial water contents and freeze-thaw cycles on characteristic parameters of water-stable aggregates and leaching loss rates of major nutrient substances were studied. A freeze-thaw cycle for specimen treatment, performed by a fast air freeze-thaw test machine, was defined as the freezing process of 12 hours at -20 ℃ in addition to the thawing process of 12 hours at +20 ℃. Except for the non-treatment, namely without freeze-thaw cycle, 7 treatments were considered to prepare the specimens, including 1 cycle, 2 cycles, 4 cycles, 8 cycles, 16 cycles, 32 cycles and 64 cycles. According to the field experience in practice, the lower and upper initial water contents of specimens were designated to be 18% and 24%, respectively. The results showed that the water-stable aggregates of the VC substrate were mainly composed of the particles with size ranging from 0.05 mm to 0.25 mm, which contained the proportions over 50% of total mass for all specimens. With increasing initial water content, the water-stable micro-aggregates transformed into the macro-aggregates, among which the particles of ≥1~2 mm were found to hold the maximum increase rate in proportion. Other parameters, which could quantitatively represent the characteristics of aggregate structure, also showed that the aggregate stability increased with initial water content. In addition, the contents of particles smaller than 0.25 mm were positively related to freeze-thaw cycles, while that of the particles larger than 0.25 mm showed the inverse trend. This indicated that the average value of aggregate particle sizes decreased with freeze-thaw cycles. It was noticed that the dispersion rates of aggregate increased with initial water content, which showed that destructive action to aggregate caused by freeze-thaw cycles was greater than the reinforcement provided by the increasing cement hydration products. Furthermore, the freeze-thaw cycles required for the aggregate characteristic parameters of VC to reach the stable state were more than that for natural soil. It may be due to that natural soil would go through the repetitive process of decomposition and aggregation, while destruction process of cement hydration products was irreversible. For the fertility, a high initial water content was associated with the increasing contents of major nutrient substances. Contents of organic matter, ammonium nitrogen (NH4+-N), available phosphorus (PO43--P) and potassium (K+) still increased with freeze-thaw cycles, while content of nitrate nitrogen (NO3--N) decreased. Moreover, the leaching losses of these nutrient substances increased with freeze-thaw cycles obviously. From the Pearson correlation analysis, the leaching loss rates of major nutrient substances were found to correlate closely with the aggregate characteristic parameters. In consideration of significance levels and absolute values of correlation coefficients, geometric mean diameter (GMD) could be suggested as the reasonable index to describe the nutrient retention ability of VC substrate. The results may contribute to illustrate the underlying reason for VC substrate fertility degradation under freeze-thaw cycles and provide theory basis for countermeasure.

Keywords: freeze-thaw cycles ; vegetation concrete ; aggregate structure ; leaching loss rate

PDF (997KB) 元数据 多维度评价 相关文章 导出 EndNote| Ris| Bibtex  收藏本文

本文引用格式

刘大翔, 刘德玉, 童标, 杨悦舒, 丁瑜, 许文年. 冻融循环作用下植被混凝土团聚结构变化对养分固持能力的影响[J]. 冰川冻土, 2022, 44(2): 623-633 doi:10.7522/j.issn.1000-0240.2022.0064

LIU Daxiang, LIU Deyu, TONG Biao, YANG Yueshu, DING Yu, XU Wennian. Effect of aggregate structure change in vegetation concrete on nutrient retention ability under freeze-thaw cycles[J]. Journal of Glaciology and Geocryology, 2022, 44(2): 623-633 doi:10.7522/j.issn.1000-0240.2022.0064

0 引言

植被混凝土生态修复技术是工程扰动裸露陡边坡植被恢复典型措施之一,已广泛应用于水利、交通、矿山边坡的植被恢复1-2。在工程应用中,需根据边坡岩土特性、坡度、坡高等来确定种植土、水泥、有机物料、活化添加剂和水的比例,并利用喷播设备将上述混合料喷播到坡面上,从而实现浅层防护与生态修复的有机结合3。当前,该技术应用范围正逐步由低纬度低海拔地区向高寒高海拔地区扩展,但冻融循环作用下因水分相变引发的材料冻胀与融沉过程,不仅导致植被混凝土物理结构疏松、力学性能降低4-5,还会使大量微生物细胞破裂死亡或进入休眠状态,导致微生物数量与活性降低,影响速效养分供给6。更重要的是,除养分含量外,降雨或径流条件下速效养分固持能力作为表征植被混凝土肥力可持续性的另一关键指标,也会显著降低。

团聚体是土壤结构的基本单元,不仅影响土壤强度,其团聚结构与孔隙形态分布等细微观结构特性还会直接影响养分元素及微生物代谢活动7。Huang等8发现土壤水稳性团聚体含量的增加会提高土壤肥力;Yan等9发现伴随团聚体破碎,土壤养分含量也随之下降;Liu等10指出不同土壤团聚体组成下,各养分物质含量差异显著;还有学者指出,不少地区土壤养分丰沛,经历冻融后的再降雨事件之后,养分会大量流失,既影响植被生长又造成环境污染11。因此,团聚体对养分的供给和维持能力体现了土壤肥力供给水平。有关冻土物理性质的研究则指出,冻融作用会显著改变土壤团聚结构,产生的膨胀力会破坏土壤颗粒间的联结,使粗颗粒中的大团聚体破碎为小团聚体,产生的挤压力使黏土颗粒中的小团聚体向中等大小团聚体聚集12-13,但对于大、中、小团聚体相互转化的界限粒径,不同研究者的结论不一,主要受到土质、含水率、冻融循环次数与模式等参数的影响14-15

基于上述土壤学领域有关团聚体与养分间联系的研究,可推测冻融循环作用下植被混凝土团聚特征发生显著变化,可能是导致养分固持能力降低的直接原因。然而,当前有关植被混凝土的研究,一方面较少涉及冻融循环对肥力指标的影响,另一方面鲜有关于细微观结构特性与养分固持能力间联系的研究报道。鉴于此,本文通过冻融循环模拟试验,探究植被混凝土团聚结构与养分固持能力的关系,有助于揭示冻融循环作用影响养分固持能力的深层原因,为植被混凝土生态修复技术在高寒地区的优化运用提供理论依据。

1 材料与方法

1.1 试验材料

本研究涉及的主要材料包括种植土、水泥、有机物料、活化添加剂和水。种植土取自宜昌周边常见黄棕壤土,经自然风干后过2 mm筛备用,其中<0.002 mm、≥0.002~0.02 mm、≥0.02~0.05 mm、≥0.05~0.25 mm、≥0.25~0.5 mm、≥0.5~1 mm、≥1~2 mm粒组含量分别为8.41%、11.55%、21.66%、38.86%、10.21%、8.98%、0.33%,pH值为6.6。水泥采用华新水泥(宜昌)有限公司生产的P.O 42.5普通硅酸盐水泥。有机物料采用湖北俏牛儿肥业有限公司提供的茶树木屑,经风干、粉碎后过1 mm筛保存备用。活化添加剂为三峡大学专利成果转化产品16,其功效为:一是在不显著影响水化过程的基础上,通过调节pH缓解碱性环境对植物的不利影响,改善功能微生物生存环境;二是富含大量固氮菌、解钾菌、解磷菌、纤维素分解菌等功能性微生物,有效提升基材活化水平。植被混凝土试样制备时,参照国家现行能源行业标准《水电工程陡边坡植被混凝土生态修复技术规范》17,各干料质量比为种植土∶水泥∶有机物料∶活化添加剂=100∶8∶4∶4。实际应用施工时,植被混凝土质量含水率通常介于18%~24%之间,因此初始含水率设计值分别取为下限值18%和上限值24%。

1.2 试样制备与试验方法

采用200 cm3容积环刀(Φ=70 mm、H=52 mm)制备试样。为保证各试样均一性,先按比例配制260 g干料,再按设计初始含水率加入定量水充分拌合后装填进环刀,可控制所有试样干密度在1.3 g·cm-3左右。试验变量设计有2种初始含水率(18%、24%)与8个冻融循环频次(0、1、2、4、8、16、32、64次)。每种初始含水率每个频次设置6个重复样,其中3个用于团聚特征与淋溶试验前养分含量测定,另外3个用于土柱淋溶试验测定养分固持能力。

试样制备完成后,立即用保鲜袋密封,再置于标准养护室[温度(20±2) ℃、湿度95%]中养护。一般认为,水泥水化反应主要在28 d内进行,反应完成度可达80%以上18,本研究设置养护周期稍大于该值。试样经30 d标准养护后,干密度为1.1~1.3 g·cm-3,渗透系数为1.1×10-3~1.3×10-3 cm·s-1,饱和含水率为62%~65%,黏聚力为42~45 kPa,内摩擦角为26°~28°,pH值为7.70~7.96。然后,将试样放入杭州雪中炭恒温技术有限公司生产的XT5405G-FSC型土工冻融循环试验箱中,采用“气冻-气融”方式,将冻结/融化温度分别设置为-20 ℃/+20 ℃,并定义冻结12 h、融化12 h为一次完整的冻融循环过程。分别在达到预定冻融循环频次时取出试样进行团聚特征、养分含量及其淋溶流失率测定。

关于实验设计,需作出以下两点说明:一是本研究主要关注含水率及冻融循环频次对植被混凝土性质的影响,为做好单因素分析和避免植物生长对实验结果的影响,未采用田间实验或盆栽实验,而采用了室内控制性实验;二是因条件所限,未能使用大型低温模拟实验室和采用“设置多个重复样方,且样方内重复取样”的方式,而是采用环刀制作重复样后放入冻融试验箱,所以本实验属于“假重复”设计。

1.3 分析测定及计算方法

植被混凝土水稳性团聚体组成参照土壤理化性质研究中常用的LB湿筛法测定19。先将试样完全风干后,置于0.075~60 mm土壤标准筛组中机械振筛20 min,然后按机械筛分后的比例重新配成50 g风干土样放在孔径分别为2 mm、1 mm、0.5 mm、0.25 mm的筛组,以30次每分钟的频率在水中上下震荡30 min,得到每个筛子上剩余各粒级水稳性团聚体含量。<0.25 mm各级微团聚体质量百分含量则采用吸管法测定20。选取平均重量直径、几何平均直径、团聚度、结构破坏率、分散率、特征微团聚体组成比例PCM与RMD、分形维数等参数表征植被混凝土团聚特征21-22。相关参数计算公式为

平均重量直径 = i=1nXiWii=1nWi
几何平均直径 = expi=1nlnXiWii=1nWi
结构破坏率 = DR0.25-WR0.25DR0.25×100%
团聚度 = n1-n2n1×100%
分散率 = n3n4×100%
PCM = n5n6×100%
RMD = n5n7×100%
分形维数=3-lgM(r<Xi)/MTlgXi/Xmax

式中:Xi 为某一粒级水稳性团聚体的平均直径(mm);Wi 为对应于Xi 的水稳性团聚体含量(%);DR0.25为>0.25 mm的机械稳定性团聚体含量(%);WR0.25为>0.25 mm的水稳性团聚体含量(%);n1为≥0.05 mm的团聚体含量(%);n2为≥0.05 mm的土颗粒含量(%);n3为<0.05 mm的团聚体含量(%);n4为<0.05 mm的土颗粒含量(%);n5为<0.02 mm的团聚体含量(%);n6为≥0.02~0.25 mm的团聚体含量(%);n7为≥0.02~2 mm的团聚体含量(%);Mr<Xi为粒径小于Xi 的团聚体质量(g);Xmax为团聚体的最大粒径(mm);MT为团聚体的总质量(g)。

对于淋溶前试样养分含量,利用机械筛分后剩余土壤测定。其中,有机质含量采用重铬酸钾容量法测定23,铵态氮、硝态氮、有效磷、速效钾含量采用荷兰产SKALAR San++连续流动分析仪测定。

对于养分淋溶流失率,采用垂直一维积水入渗法测定,环刀试样底部用纱布封住,顶部再放置一个同规格环刀,接缝处用透明胶带密封后注入双蒸水。待试样饱和下部滴水后,再用双蒸水注满环刀,同时开始用漏斗和锥形瓶收集淋溶液。当收集淋溶液达100 mL后,停止淋溶试验。测定淋溶液养分含量,按下式可计算各养分淋溶流失率。

Ii=Vkimni×100%

式中:m为完整试样干重(kg);ni 为淋洗前试样单位质量某养分指标含量(mg·kg-1);V为收集的淋洗液体积(L);ki 为收集的淋洗液中某养分指标浓度(mg·L-1)。

采用SPSS 24.0统计软件进行Waller-Duncan差异性分析,并对植被混凝土团聚体特征参数与各养分淋溶流失率进行Pearson相关性分析。

2 结果与分析

2.1 水稳性团聚体的粒径分布

含水率是影响土壤水稳性团聚体粒径分布的重要指标24。如表1所示,两种初始含水率植被混凝土试样中皆以≥0.05~0.25 mm粒组含量为主,所占比例均超过总量的50%。不论冻融前后,初始含水率高的试样中≥1~2 mm、≥0.02~0.05 mm、≥0.002~0.02 mm、<0.002 mm四个粒组含量均偏大,而≥0.5~1 mm、≥0.25~0.5 mm、≥0.05~0.25 mm三个粒组含量均偏低;其中≥1~2 mm与≥0.05~0.25 mm两粒组含量相差较大。总体上,初始含水率的提高促使试样中水稳性团聚体平均粒径增大。

表1   不同初始含水率与冻融循环次数下植被混凝土水稳性团聚体的粒径分布

Table 1  Water-stable aggregate particle size distribution in vegetation concrete under different initial water contents and freeze-thaw cycles

初始含水率/%冻融循环次数不同粒径的质量分数/%
≥1~2 mm≥0.5~1 mm≥0.25~0.5 mm≥0.05~0.25 mm≥0.02~0.05 mm≥0.002~0.02 mm<0.002 mm
1800.83±0.12a9.83±0.31a11.70±0.28a55.36±2.21a13.69±0.36a6.03±0.35a2.56±0.13a
10.65±0.03b8.24±0.23b10.87±0.29b56.11±1.23a14.21±0.25ab7.29±0.28b2.63±0.16a
20.53±0.05bc7.96±0.26b9.76±0.15c56.68±3.15a14.20±0.28ba8.26±0.27c2.61±0.21a
40.51±0.08bc7.54±0.14c8.79±0.34d57.68±2.36a14.35±0.14bc8.44±0.23cd2.69±0.09a
80.50±0.03bc6.42±0.08d8.43±0.19de58.72±4.20a14.34±0.26bc8.88±0.19de2.71±0.11a
160.48±0.14c5.87±0.14e8.13±0.13ef58.80±3.46a14.88±0.31c9.05±0.24e2.79±0.18a
320.47±0.04c5.35±0.15f7.94±0.16f59.05±2.65a14.76±0.23bc9.61±0.31f2.82±0.23a
640.47±0.05c5.12±0.16f7.85±0.12f59.20±2.78a14.66±0.41bc9.87±0.26f2.83±0.14a

对数拟合

y=alnx+b

a-0.0180-0.2050-0.18200.17500.04860.16920.0113
b0.55127.00137.001357.734014.39608.46182.7072
R20.89800.68130.68150.60440.70870.77930.5342
2406.41±0.18a9.25±0.26a11.65±0.26a51.41±2.63a14.16±0.16a6.41±0.26a2.71±0.19a
14.57±0.12b8.47±0.12b11.02±0.14b51.60±3.56ab14.49±0.32ab7.08±0.19b2.77±0.20ab
24.40±0.05b7.15±0.25c9.60±0.25c53.43±3.43abc14.03±0.18a8.56±0.24c2.83±0.12ab
43.17±0.03c6.48±0.14d8.76±0.13d54.44±2.15abc15.17±0.21dc9.01±0.34cd2.96±0.08abc
82.58±0.14d5.83±0.13e8.33±0.16e55.54±3.01abc15.48±0.24d9.17±0.25de3.07±0.13bc
162.27±0.02e5.03±0.39g7.46±0.13f57.71±1.65c14.95±0.22bc9.39±0.16def3.19±0.17c
322.17±0.09e5.59±0.10ef7.23±0.16f56.96±2.21bc15.21±0.31dc9.58±0.35ef3.26±0.22c
642.09±0.08e5.19±0.14fg6.57±0.18g57.99±1.26c15.09±0.19dc9.83±0.21f3.24±0.16c

对数拟合

y=alnx+b

a-0.2060-0.1910-0.21400.27600.04880.15760.0233
b3.41726.58658.785854.939014.83208.65953.0083
R20.77700.65160.59850.48590.36630.70400.4954

注:数值后不同的小写字母表示相同含水率条件下不同冻融次数间差异性显著(P<0.05)。

新窗口打开| 下载CSV


表1可见,随冻融循环次数增加,两种初始含水率植被混凝土≥1~2 mm、≥0.5~1 mm、≥0.25~0.5 mm粒组含量均呈降低趋势,且在冻融初期变化较显著,当冻融循环频次超过32次后才逐步趋于稳定,到64次循环时18%与24%含水率试样中≥0.25 mm团聚体质量分数相比冻融前降幅分别达到39.89%和49.28%。而≥0.05~0.25 mm、≥0.02~0.05 mm、≥0.002~0.02 mm、<0.002 mm粒组含量均呈增加趋势,且以≥0.05~0.25 mm与≥0.002~0.02 mm两个粒组含量变化较明显。可见,冻融循环促使植被混凝土水稳性团聚体平均粒径减小。

2.2 水稳性团聚体的特征参数

平均重量直径、几何平均直径、团聚度、破坏率、分散率、特征微团聚体组成比例(PCM、RMD)和分形维数被广泛作为反映团聚体稳定性特征的评定指标21-22。初始含水率与冻融循环对植被混凝土水稳性团聚体特征参数的影响见表2。由表可知,未经冻融时,随初始含水率提高,植被混凝土平均重量直径、几何平均直径与团聚度均略大,而分散率、<0.02 mm特征微团聚体组成比例与分形维数均偏小。随冻融循环次数增加,两种初始含水率植被混凝土平均重量直径、几何平均直径与团聚度呈降低趋势,破坏率、分散率、<0.02 mm特征微团聚体组成比例与分形维数均呈增加趋势。可见,冻融循环会破坏植被混凝土水稳性团聚体稳定性,且冻融初期的破坏效应更明显。

表2   不同初始含水率与冻融循环次数下植被混凝土水稳性团聚体的特征参数

Table 2  Water-stable aggregate characteristic parameters in vegetation concrete under different initial water contents and freeze-thaw cycles

初始含水率/%冻融循环次数平均重量 直径/mm几何平均 直径/mm团聚度/%破坏率/%分散率/%特征微团聚体组成比例分形维数
PCM/%RMD/%
1800.23±0.02a0.47±0.07a21.05±1.03a11.76±1.12a57.66±3.16a12.44±0.26a9.40±0.18a2.45±0.01a
10.21±0.01ab0.46±0.05a17.44±0.65b14.68±0.95ab64.59±2.34b14.11±0.15b11.01±0.05b2.47±0.01a
20.21±0.01ab0.45±0.11a16.70±0.48b17.19±1.03bcd66.71±1.57b15.34±0.18c12.20±0.16c2.47±0.02a
40.20±0.02ab0.45±0.05a16.28±0.56b15.63±0.87bc67.75±2.28bc15.45±0.09c12.52±0.22c2.47±0.01a
80.19±0.01b0.44±0.06a13.10±0.67c18.86±1.66cde72.78±2.61cd15.86±0.17d13.11±0.17d2.47±0.02a
160.19±0.02b0.44±0.04a11.49±1.04cd20.54±2.75de76.04±3.21de16.07±0.11d13.43±0.18d2.48±0.03a
320.18±0.03b0.44±0.07a9.93±0.95d18.52±1.56cde78.99±3.65e16.84±0.13e14.19±0.13e2.48±0.01a
640.18±0.01b0.44±0.05a10.23±1.27d21.65±2.64e78.64±2.19e17.19±0.16f14.55±0.12f2.48±0.02a

对数拟合

y=alnx+b

a-0.0020-0.0010-0.48300.40080.93580.20780.22460.0014
b0.19830.448514.433017.432070.578015.453012.59502.4715
R20.72960.74940.64440.66120.67070.79980.75730.8799
2400.30±0.02a0.49±0.08a21.70±1.08a12.17±0.96a55.47±1.72a10.86±0.14a7.67±0.07a2.31±0.01a
10.27±0.03ab0.48±0.06a17.35±1.73b14.53±1.32a64.96±2.21b14.90±0.15b10.93±0.11b2.47±0.02b
20.25±0.03bc0.47±0.09a16.22±0.35b12.66±0.93a67.75±3.04b16.88±0.19c12.85±0.14c2.48±0.01b
40.23±0.02bcd0.46±0.07a13.64±0.69c19.06±1.02b73.19±2.15c17.20±0.17cd13.60±0.19d2.49±0.01b
80.22±0.01cd0.45±0.12a10.68±1.12d19.71±0.75b78.22±2.37d17.23±0.15d13.95±0.16e2.49±0.02b
160.21±0.04cd0.45±0.04a9.91±0.73d20.98±1.65bc79.31±1.65d17.31±0.09d14.39±0.05f2.50±0.03b
320.21±0.02cd0.45±0.06a6.82±0.85e22.66±2.13c85.10±0.96e17.79±0.21e14.73±0.14g2.50±0.01b
640.20±0.01d0.44±0.02a5.97±0.64e21.55±1.64bc86.78±2.08e17.89±0.16e15.04±0.18h2.50±0.01b

对数拟合

y=alnx+b

a-0.0050-0.0020-0.66500.44301.34590.348960.35220.0098
b0.23540.460812.657018.002074.110016.326012.96402.4694
R20.74340.64920.64510.48890.68900.93850.87500.9934

注:数值后不同的小写字母表示相同含水率条件下不同冻融次数间差异性显著(P<0.05);团聚体特征参数的定义见1.3节。

新窗口打开| 下载CSV


2.3 养分含量及其淋溶流失率

初始含水率与冻融循环对植被混凝土养分含量的影响如表3所示。由表可知,初始含水率高的试样中有机质、铵态氮、硝态氮、有效磷、速效钾含量均略大。而随冻融循环次数增加,植被混凝土中铵态氮、有效磷、速效钾含量均呈增加趋势,有机质含量呈先增加后降低趋势,硝态氮含量呈降低趋势。冻融循环初期,有机质、有效磷、速效钾含量的增长与硝态氮含量的下降较快,而铵态氮含量增速较慢;后期铵态氮含量增速变快,而有效磷、速效钾含量增速与有机质、硝态氮含量降低速度变缓。

表3   不同初始含水率与冻融循环次数下植被混凝土的主要养分含量

Table 3  Contents of major nutrient substances in vegetation concrete under different initial water contents and freeze-thaw cycles

初始含水率/%冻融循环次数主要养分含量/(mg·kg-1
有机质铵态氮硝态氮有效磷速效钾
18014.99±0.85a22.37±1.43a16.89±1.12a170.93±2.53a189.82±1.61a
116.86±1.23ab23.26±1.65a14.75±0.52b187.86±2.92b213.24±2.27b
218.23±0.99b24.15±0.97ab14.23±0.36bc200.45±1.83c224.73±2.34c
418.69±1.31b26.47±1.37bc13.96±0.43bcd223.37±4.62d238.94±1.92d
818.31±0.88b29.23±1.96c13.65±0.61bcd241.31±3.16e256.71±3.04e
1618.09±0.91b33.41±1.31d13.38±0.26cde245.29±2.65ef260.54±2.65ef
3218.11±1.25b37.94±2.01e13.03±0.22de247.18±3.05ef263.15±1.46fg
6417.87±1.02b39.15±1.45e12.54±0.31e249.79±2.64f267.43±3.09g

对数拟合

y=alnx+b

a0.16430.6157-0.19203.67993.5675
b17.676029.61804.0160221.4900240.0200
R20.81770.37400.89420.62690.7075
24015.12±0.86a22.81±0.99a17.51±0.94a174.80±1.69a193.57±1.83a
117.26±1.09b23.47±1.09ab15.54±0.68b197.60±1.42b224.19±3.12b
218.73±1.17bc24.69±1.35ab14.50±0.59bc208.49±2.31c226.98±2.92b
419.48±0.56c26.31±1.63b14.32±0.57bcd225.46±2.53d247.83±2.65c
818.91±0.91bc29.54±0.92c13.65±0.67cde244.00±1.68e260.36±3.05d
1618.36±0.82bc33.76±1.76d13.37±0.34cde249.90±3.24f268.95±1.94e
3218.27±1.20bc38.21±1.53e13.21±0.51de250.16±2.37f270.14±2.68e
6418.09±1.04bc40.18±1.96e12.84±0.48e257.32±2.68g271.23±2.46e

对数拟合

y=alnx+b

a0.17550.6172-0.21503.72683.6792
b18.062029.992014.3250226.6900246.1200
R20.74150.35940.85340.67980.7410

注:数值后不同的小写字母表示相同含水率条件下不同冻融次数间差异性显著(P<0.05)。

新窗口打开| 下载CSV


淋溶流失率可直接反映土壤养分固持能力25。由表4可见,不论冻融循环前后,随初始含水率提高,植被混凝土各养分淋溶流失率均略有降低。随冻融循环次数增加,各养分淋溶流失率均呈增加趋势。其中,硝态氮与速效钾淋溶流失率绝对值始终较高,有机质则较低。但就增幅率而言,有机质和硝态氮最高,两种含水率条件下64次循环时的淋失率相比冻融前的增幅率均超过90%;铵态氮淋失率对应的增幅率最低,两种含水率条件下均低于50%。总体而言,冻融循环作用会显著弱化植被混凝土养分固持能力。

表4   不同初始含水率与冻融循环次数下植被混凝土的主要养分淋溶流失率

Table 4  Leaching loss rates of major nutrient substances in vegetation concrete under different initial water contents and freeze-thaw cycles

初始含水率/%冻融循环次数主要养分淋溶流失率/%
有机质铵态氮硝态氮有效磷速效钾
1808.94±0.18a14.53±0.13a13.47±0.16a14.67±0.21a15.29±0.13a
19.12±0.21a15.24±0.19b15.76±0.11b14.85±0.14a23.42±0.19b
210.11±0.16b15.98±0.11c16.92±0.23c15.76±0.17b23.56±0.20b
411.24±0.22c17.21±0.23d17.18±0.16c16.14±0.16c24.11±0.16c
813.85±0.23d18.14±0.12e18.37±0.17d16.69±0.14d24.73±0.24d
1615.36±0.14e19.32±0.24f21.26±0.21e17.73±0.11e25.22±0.15e
3216.93±0.16f19.78±0.32g22.53±0.13f18.29±0.22f25.81±0.13f
6417.08±0.31f20.47±0.18h25.94±0.42g20.07±0.18g25.63±0.14f

对数拟合

y=alnx+b

a0.32860.24130.43240.17730.5190
b12.893017.631019.013016.810023.5730
R20.40350.51930.49380.40330.9945
2407.94±0.19a13.63±0.14a12.51±0.16a12.64±0.20a13.31±0.17a
18.23±0.12a13.25±0.16a14.03±0.22b13.11±0.13b22.63±0.18c
29.06±0.13b14.34±0.11b15.52±0.18c15.39±0.17c20.90±0.27b
411.15±0.18c14.75±0.28c18.72±0.15d14.03±0.12c23.55±0.23d
812.27±0.23d15.57±0.24d17.29±0.16e13.87±0.26d26.00±0.17f
1613.02±0.17e15.76±0.16d20.12±0.23f16.05±0.17e26.25±0.14f
3216.04±0.16f17.35±0.17e21.50±0.17g17.93±0.11f25.92±0.11f
6416.42±0.21g19.89±0.25f25.78±0.34h19.50±0.14g24.53±0.25e

对数拟合

y=alnx+b

a0.32200.17790.45160.22060.6169
b11.829015.602018.272015.358023.0070
R20.41040.28900.47550.36290.8940

注:数值后不同的小写字母表示相同含水率条件下不同冻融次数间差异性显著(P<0.05)。

新窗口打开| 下载CSV


2.4 水稳性团聚体的特征参数与养分淋溶流失率间的相关性分析

利用表2表4数据,基于2种初始含水率与8种冻融循环频次条件下测试结果,开展植被混凝土水稳性团聚体特征参数与各养分淋溶流失率的相关性分析,结果如表5所示。其中,植被混凝土养分淋溶流失率与破坏率、分散率、<0.02 mm特征微团聚体组成比例和分形维数呈正相关,而与平均重量直径、几何平均直径和团聚度呈负相关,且均达到极显著水平(P<0.01)。从Pearson相关性系数绝对值大小来看,团聚结构参数与养分淋失率的相关性强弱排序为:几何平均直径>团聚度≈分散率>破坏率≈RMD≈平均重量直径>PCM>分形维数。因此可以推断,上述团聚体结构特征参数中,几何平均直径最适合用于反映植被混凝土养分固持能力,几何平均直径越大,养分固持能力越强。

表5   冻融循环作用下植被混凝土水稳性团聚体的特征参数与主要养分淋溶流失率的相关系数

Table 5  Pearson correlation coefficents between water-stable aggregate characteristic parameters in vegetation concrete and leaching loss rates of major nutrient substances under freeze-thaw cycles

平均重量直径几何平均直径团聚度破坏率分散率PCMRMD分形维数
有机质淋失率-0.771**-0.839**-0.890**0.866**0.876**0.694**0.811**0.492**
铵态氮淋失率-0.825**-0.845**-0.717**0.705**0.702**0.532**0.676**0.398**
硝态氮淋失率-0.738**-0.810**-0.888**0.864**0.881**0.752**0.845**0.550**
有效磷淋失率-0.783**-0.814**-0.739**0.686**0.726**0.597**0.714**0.484**
速效钾淋失率-0.752**-0.794**-0.805**0.812**0.822**0.866**0.893**0.818**

注:**表示在0.01水平上显著相关;n=16,包含2种含水率与8个冻融循环频次的对应数据;团聚体特征参数的定义见1.3节。

新窗口打开| 下载CSV


3 讨论

3.1 初始含水率与冻融循环次数对植被混凝土水稳性团聚体的粒径和特征参数的影响

所有试样团聚体粒径分布均以≥0.05~0.25 mm粒组含量为主,这与配制植被混凝土所用种植土粒径级配中≥0.05~0.25 mm粒组最多有关,且产生的水泥水化胶结物也促进了<0.05 mm团聚体向更大团聚体转化。但至于为何转化界限是0.05 mm,暂未找到明确解释,猜测可能与水泥用量有关。随着初始含水率提高,水稳性微团聚体进一步向大团聚体转化,且尤其以≥1~2 mm粒组的增多最明显。未经冻融时,高含水率试样平均重量直径、几何平均直径、破坏率和团聚度略大,分散率、<0.02 mm特征微团聚体组成比例、分形维数略低,原因可能为冻融前初始含水率越高,则水泥水化反应越完全,有助于形成更多大粒径团聚体。而冻融后,高含水率试样团聚度显著偏小、分散率显著偏大,在于高含水率会产生更强烈的相变效应,更大冻胀力造成团聚体破碎程度更明显26。因此,对于高含水率试样,水分相变对团聚体的削弱效应可能超出了水化产物增多带来的增强效应。

冻融循环初期对植被混凝土团聚结构的影响较明显,随冻融频次增长逐渐趋于稳定。有学者发现普通土壤也存在类似规律27,原因可能是初期团聚结构相对完整,经冻融作用时破碎效应更剧烈,会快速形成大量小粒径团聚体;而小粒径团聚体抵抗挤压与收缩能力较强,经过反复冻融作用也不易崩解破碎,因而冻融后期团聚结构趋于稳定。此外,团聚作用还与微生物数量与活性有关,因新陈代谢产生的分泌物有助于团聚体形成28。冻融初期,大量微生物死亡或进入休眠状态,分泌物的减少势必弱化土颗粒胶结作用,显著降低团聚体稳定性;但仍有部分低温耐受性强的微生物新陈代谢活动依旧进行,植被混凝土中微生物数量与活性逐步达到稳态,也促使团聚结构趋于稳定。

同等条件下,普通土壤团聚结构特征参数变幅和达到稳态所需冻融循环频次显著小于植被混凝土。如Zhang等29研究发现人工重塑黏土团聚体粒径在前6次冻融循环时变幅最显著,其中≥1~2 mm粒组含量在40次冻融循环后降幅在5%以内。而本研究中18%与24%含水率试样在32次冻融循环后≥1~2 mm粒组含量降幅便已分别达到43.37%和66.15%,之后逐步趋于稳定。原因在于,普通土壤团聚体在冻融时会经历“解聚—重聚—再解聚—再重聚”的反复过程30,这也是其冻融后期趋于稳态的主因;而植被混凝土成分类似水泥土,既有土壤又有水泥水化产物,由于水泥水化产物破坏过程不可逆,其团聚结构达到稳定的时刻是水化产物被破坏到无法再被进一步破坏的时刻(图1)。

图1

图1   冻融循环作用下普通土壤与植被混凝土结构变化过程示意图

Fig. 1   Sketches showing the structure destruction process of natural soil and vegetation concrete under freeze-thaw cycles


3.2 初始含水率与冻融循环次数对植被混凝土的养分和固持能力的影响

冻融循环前,初始含水率的提高促使试样养分含量增多和固持能力增强。究其原因,可能是:①高含水率条件下水泥水化更完全,试样pH值增大可能杀死更多微生物,导致其体内营养物质流出31;②部分养分元素被水化胶结物包裹与吸附,导致水溶性游离养分变少。冻融循环后,高含水率试样养分淋溶流失率依然偏小,与前文中提到的冻融时高含水率试样分散率、破坏率等参数偏大的现象看似矛盾,但实质上是由于高含水率会造成试样团聚体中≥1~2 mm粒组质量分数远高于低含水率试样,也侧面反映了大粒径团聚体对试样中养分的固持占主要贡献。

随着冻融循环频次增多,有机质、有效磷和速效钾含量仍逐步提升,原因在于,虽然冻融环境降低了微生物总量与活性6,抑制了难溶性养分向速效养分转化,但死亡微生物体内养分的析出32,以及低温耐受性微生物的不断繁殖,仍会使养分含量增长。至于铵态氮与硝态氮含量与冻融频次的关系,目前土壤学领域说法不一,有学者发现冻融循环显著增加了土壤中铵态氮含量,并降低了硝态氮含量33,但单博等34的研究结果却与之相反。本文研究结果与前者一致,原因可能是冻融循环在抑制有机元素矿化的同时促进了土壤反硝化作用35,且碱性环境也抑制了硝化细菌活性,减少了铵态氮向硝态氮转化。

随冻融循环频次增多,各养分淋溶流失率均显著增高,原因可能为:①包裹在团聚体内部的营养元素伴随着团聚体破碎大量析出36,因而养分淋溶流失率增大;②冻融循环致使团粒间空隙膨胀和收缩,使团聚体重新排列,结构孔隙率增大,淋溶阻力减小,影响营养元素附着能力,导致更多养分元素以游离状态存在于水相中,并随水分发生迁移37;③团聚体破碎过程中,材料比表面积增大,但吸附位点增速小于养分元素析出速度。

3.3 冻融循环作用下植被混凝土水稳性团聚体的特征参数与养分固持能力的关系

土壤学领域研究表明,土壤团聚结构与养分固持能力关系密切。但因团聚结构特征参数众多,究竟何种参数最适合表征养分固持能力仍未达成共识。如区晓琳等38研究表明团聚体平均粒径越大,养分固持能力越强;Guidi等39发现团聚体稳定性下降会导致养分固持能力下降;Cui等40发现土壤平均重量直径越大养分固持能力越强;而陈秋捷等41发现沙化土壤养分固持能力可由平均重量直径反映。本研究中发现植被混凝土中几何平均直径与各养分淋溶流失率的Pearson相关系数绝对值最大,且达到极显著水平(P<0.01),因此建议将几何平均直径作为评判植被混凝土养分固持能力的团聚特征指标。

4 结论

通过对冻融循环作用下植被混凝土水稳性团聚体粒径分布、特征参数、主要养分含量及其淋溶流失率开展研究,主要认识和结论如下:

(1)随初始含水率的提高,植被混凝土中水稳性微团聚体向水稳性大团聚体转化,且通过团聚体特征参数也反映出团聚体稳定性随之提高。冻融循环促使植被混凝土中水稳性团聚体平均粒径不断减小,但会随冻融频次增长逐步趋于稳定。

(2)初始含水率的提高促使植被混凝土中各养分含量略微增加。冻融循环作用下,有机质、铵态氮、有效磷、速效钾含量仍有增长,但硝态氮含量则不断降低。同时,冻融循环还会导致各养分固持能力不断降低,且也会随冻融频次增长逐步趋于稳定。

(3)综合考虑显著性水平与相关性系数绝对值,认为团聚体特征参数中几何平均直径与各养分淋失率相关程度最高,最适合用于表征植被混凝土养分固持能力。

参考文献

Zhao BingqinXia ZhenyaoXu Wennianet al.

Review on research of slope eco-restoration technique for engineering disturbed area

[J]. Water Resources and Hydropower Engineering, 2017482): 130-137.

[本文引用: 1]

赵冰琴夏振尧许文年.

工程扰动区边坡生态修复技术研究综述

[J]. 水利水电技术, 2017482): 130-137.

[本文引用: 1]

Zhao BingqinXia LuXia Donget al.

Effect of cement content in vegetation concrete on soil physico-chemical properties, enzyme activities and microbial biomass

[J]. Nature Environment and Pollution Technology, 2018174): 1065-1075.

[本文引用: 1]

Xu WennianXia DongZhao Bingqinet al. Research on vegetation ecological restoration technology in disturbed areas of hydropower projects[M]. BeijingScience Press2019108-113.

[本文引用: 1]

许文年夏栋赵冰琴. 水电工程扰动区植被生态修复技术研究[M]. 北京科学出版社2019108-113.

[本文引用: 1]

Zhou MingtaoYang PingHu Huanet al.

Experimental study on freezing and thawing actions of vegetation-growing concrete ecological base material

[J]. Research of Soil and Water Conservation, 2013202): 282-287.

[本文引用: 1]

周明涛杨平胡欢.

植被混凝土生态基材冻融效应试验研究

[J]. 水土保持研究, 2013202): 282-287.

[本文引用: 1]

Liang YongzheChen YiLiu Daxianget al.

Effect of additive plant fiber on shearing strength of vegetation-compatible concrete under freezing-thawing cycles

[J]. Bulletin of Soil and Water Conservation, 2016362): 136-139.

[本文引用: 1]

梁永哲陈毅刘大翔.

外掺植物纤维对冻融作用下植被混凝土抗剪强度的影响

[J]. 水土保持通报, 2016362): 136-139.

[本文引用: 1]

Zhang LinyaoLiu DaxiangXu Wennianet al.

A study on the change of three functional microorganism quantities in habitat substrate under freezing-thawing cycles

[J]. Journal of Glaciology and Geocryology, 2017395): 1122-1129.

[本文引用: 2]

张琳瑶刘大翔许文年.

冻融循环条件下生境基材中三种功能微生物数量变化规律研究

[J]. 冰川冻土, 2017395): 1122-1129.

[本文引用: 2]

Zhang XianfengZhu AnningZhang Jiabaoet al.

Research on relationship between soil nutrient fertility and aggregation of Fluvo-aquic soil under intensive cultivation

[J]. Soil, 2017491): 33-39.

[本文引用: 1]

张先凤朱安宁张佳宝.

集约化种植下潮土养分肥力与团聚体特征相互关系研究

[J]. 土壤, 2017491): 33-39.

[本文引用: 1]

Huang ShanPeng XianxianHuang Qianruet al.

Soil aggregation and organic carbon fractions affected by long-term fertilization in a red soil of subtropical China

[J]. Geoderma, 20101543/4): 364-369.

[本文引用: 1]

Yan YuchunWang XuGuo Zhenjieet al.

Influence of wind erosion on dry aggregate size distribution and nutrients in three steppe soils in northern China

[J]. Catena, 2018170159-168.

[本文引用: 1]

Liu XiaoliHe YuanqiuZhang Hailinet al.

Impact of land use and soil fertility on distributions of soil aggregate fractions and some nutrients

[J]. Pedosphere, 2010205): 666-673.

[本文引用: 1]

Li LiangyongLiu FengLi Fanet al.

Effects of different fertilizer ratio on nutrient leaching in tobacco fields of south China

[J]. Chinese Tobacco Science, 2009302): 47-52.

[本文引用: 1]

李良勇刘峰李帆.

不同肥料配比对南方烟田土壤养分淋溶的影响

[J]. 中国烟草科学, 2009302): 47-52.

[本文引用: 1]

Zhang ZeMa WeiFeng Wenjieet al.

Reconstruction of soil particle composition during freeze-thaw cycling: a review

[J]. Pedosphere, 2016262): 167-179.

[本文引用: 1]

Niu HaoLuo WanqingWang Jinfenget al.

Effects of freeze-thaw on the composition and stability of air-dried and water-stable aggregates of black soil in Northeast China

[J]. Chinese Journal of Soil Science, 2020514): 841-847.

[本文引用: 1]

牛浩罗万清王晋峰.

冻融对东北黑土风干团聚体与水稳性团聚体组成及稳定性的影响

[J]. 土壤通报, 2020514): 841-847.

[本文引用: 1]

Wang EnhengZhao YusenChen Xiangwei.

Effects of seasonal freeze-thaw cycle on soil aggregate characters in typical phaeozem region of Northeast China

[J]. Chinese Journal of Applied Ecology, 2010214): 889-894.

[本文引用: 1]

王恩姮赵雨森陈祥伟.

季节性冻融对典型黑土区土壤团聚体特征的影响

[J]. 应用生态学报, 2010214): 889-894.

[本文引用: 1]

Li GuiyuanFan Haoming.

Effect of freeze-thaw on water stability of aggregates in a black soil of Northeast China

[J]. Pedosphere, 2014242): 285-290.

[本文引用: 1]

Xu WennianWang Tieqiao.

Preparation method of green additive for vegetation concrete

01138343.7[P]. 2002-07-17.

[本文引用: 1]

许文年王铁桥.

混凝土绿化添加剂的制备方法

01138343.7[P]. 2002-07-17.

[本文引用: 1]

Technical code for eco-restoration of vegetation concrete on steep slope of hydropower projects: NB/T 35082—2016 [S]. BeijingChina Electric Power Press2016.

[本文引用: 1]

水电工程陡边坡植被混凝土生态修复技术规范: NB/T 35082—2016 [S]. 北京中国电力出版社2016.

[本文引用: 1]

Huang Zhengyu. Construction materials[M]. BeijingChina Architecture & Building Press201152-60.

[本文引用: 1]

黄政宇. 土木工程材料[M]. 北京中国建筑工业出版社201152-60.

[本文引用: 1]

Le Bissonnais Y.

Aggregate stability and assessment of soil crustability and erodibility: I. theory and methodology

[J]. European Journal of Soil Science, 2016671): 11-21.

[本文引用: 1]

Wang Da’anLiu GangWang Xiangyinget al.

Comparative study on particle size distribution of eroded sediment by laser method and pipette method in black soil region of Northeast China

[J]. Science of Soil and Water Conservation, 2016141): 114-122.

[本文引用: 1]

王大安刘刚王翔鹰.

用激光法和吸管法测定东北黑土区侵蚀泥沙颗粒组成的差异分析

[J]. 中国水土保持科学, 2016141): 114-122.

[本文引用: 1]

Guo LinghuiZhang WenxuGao Jiangboet al.

Stability features and evolution mechanism of soil water-stable aggregates in Pinus tabulaeformis plantation in Taihang Mountain

[J]. Research of Environmental Sciences, 20193211): 1861-1868.

[本文引用: 2]

郭灵辉张文旭高江波.

太行山油松人工林土壤水稳性团聚体稳定性及其演变机制

[J]. 环境科学研究, 20193211): 1861-1868.

[本文引用: 2]

Lin QingmeiLiao ChaolinDai Qiet al.

Effect of long-term fertilization and groundwater level on microaggregate distribution and its fractal feature in red paddy soil

[J]. Chinese Journal of Soil Science, 2018496): 1397-1404.

[本文引用: 2]

林清美廖超林戴齐.

长期施肥与地下水位对红壤性水稻土微团聚体及其分形特征的影响

[J]. 土壤通报, 2018496): 1397-1404.

[本文引用: 2]

Ye QinJiang XueqinLi Xicanet al.

Comparison on inversion model of soil organic matter content based on hyperspectral data

[J]. Transactions of the Chinese Society for Agricultural Machinery, 2017483): 164-172.

[本文引用: 1]

叶勤姜雪芹李西灿.

基于高光谱数据的土壤有机质含量反演模型比较

[J]. 农业机械学报, 2017483): 164-172.

[本文引用: 1]

Xu ChengGu FengWang Yaoet al.

Study on the relationships between soil aggregate and water dynamics under three vegetation cover

[J]. Journal of Soil and Water Conservation, 2019331): 68-74.

[本文引用: 1]

徐程谷峰王瑶.

土壤团聚体和水分动态在3种植被覆盖下的关系

[J]. 水土保持学报, 2019331): 68-74.

[本文引用: 1]

Tong BiaoLiu DaxiangXu Wennianet al.

Effects of freezing and thawing cycles on vegetation concrete nutrients and its retention ability

[J]. Yangtze River, 2018493): 87-92.

[本文引用: 1]

童标刘大翔许文年.

冻融循环对植被混凝土养分及其固持能力的影响

[J]. 人民长江, 2018493): 87-92.

[本文引用: 1]

Li XiaolinWang HongjianZou Shaojunet al.

Research state of deformation characteristics of frozen soil under cyclic loading and problems in frozen soil excavation

[J]. Journal of Glaciology and Geocryology, 2017391): 92-101.

[本文引用: 1]

栗晓林王红坚邹少军.

循环荷载下冻土变形特性研究现状及冻土开挖问题

[J]. 冰川冻土, 2017391): 92-101.

[本文引用: 1]

Wang HengxingYang Lin.

Experimental study on the reinforcement of herbaceous plant roots under freezing-thawing cycles

[J]. Journal of Glaciology and Geocryology, 2018404): 792-801.

[本文引用: 1]

王恒星杨林.

冻融作用下草本植物根系加固土体试验研究

[J]. 冰川冻土, 2018404): 792-801.

[本文引用: 1]

Miura MHill P WJones D L.

Impact of a single freeze-thaw and dry-wet event on soil solutes and microbial metabolites

[J/OL]. Applied Soil Ecology, 20201531036362021-10-10]. .

[本文引用: 1]

Zhang ZePendin V VFeng Wenjieet al.

The influence of freeze-thaw cycles on the granulometric composition of Moscow morainic clay

[J]. Sciences in Cold and Arid Regions, 201573): 199-205.

[本文引用: 1]

Jin WanpengFan HaomingLiu Boet al.

Effects of freeze-thaw cycles on aggregate stability of black soil

[J]. Chinese Journal of Applied Ecology, 20193012): 4195-4201.

[本文引用: 1]

金万鹏范昊明刘博.

冻融交替对黑土团聚体稳定性的影响

[J]. 应用生态学报, 20193012): 4195-4201.

[本文引用: 1]

Liu LeiWang YuboGai Zhijiaet al.

Responses of soil microorganisms and enzymatic activities to alkaline stress in sugar beet rhizosphere

[J]. Polish Journal of Environmental Studies, 2020291): 739-748.

[本文引用: 1]

Miura MJones T GHill P Wet al.

Freeze-thaw and dry-wet events reduce microbial extracellular enzyme activity, but not organic matter turnover in an agricultural grassland soil

[J]. Applied Soil Ecology, 2019144196-199.

[本文引用: 1]

Watanabe TTateno RImada Set al.

The effect of a freeze-thaw cycle on dissolved nitrogen dynamics and its relation to dissolved organic matter and soil microbial biomass in the soil of a northern hardwood forest

[J]. Biogeochemistry, 2019142319-338.

[本文引用: 1]

Shan BoZhuang HaiyanChen Xiangwei.

Nitrogen forms in plough layer of black soil under simulated freezing and thawing conditions

[J]. Journal of Northeast Forestry University, 2018466): 73-76.

[本文引用: 1]

单博庄海燕陈祥伟.

冻融时黑土耕层土壤氮素形态

[J]. 东北林业大学学报, 2018466): 73-76.

[本文引用: 1]

Song YangYu XiaofeiZou Yuanchunet al.

Progress of freeze-thaw effects on carbon, nitrogen and phosphorus cyclings in soils

[J]. Soils and Crops, 201652): 78-90.

[本文引用: 1]

宋阳于晓菲邹元春.

冻融作用对土壤碳、氮、磷循环的影响

[J]. 土壤与作物, 201652): 78-90.

[本文引用: 1]

Han LuWan ZhongmeiSun Heyang.

Research progress on the effects of freezing and thawing on soil physical, chemical and biological properties

[J]. Chinese Journal of Soil Science, 2018493): 736-742.

[本文引用: 1]

韩露万忠梅孙赫阳.

冻融作用对土壤物理、化学和生物学性质影响的研究进展

[J]. 土壤通报, 2018493): 736-742.

[本文引用: 1]

Fan JihuiCao YingziYan Yanet al.

Freezing-thawing cycles effect on the water soluble organic carbon, nitrogen and microbial biomass of alpine grassland soil in northern Tibet

[J]. African Journal of Microbiology Research, 201263): 562-567.

[本文引用: 1]

Xiaolin OuChen ZhibiaoJiang Chaoet al.

Effect of vegetation restoration on nutrient distribution within aggregate of subtropical eroded red soils

[J]. Journal of Soil and Water Conservation, 2016306): 230-238.

[本文引用: 1]

区晓琳陈志彪姜超.

植被恢复对亚热带侵蚀红壤团聚体养分分布的影响

[J]. 水土保持学报, 2016306): 230-238.

[本文引用: 1]

Guidi PAntisari L VMarè B Tet al.

Effects of alfalfa on aggregate stability, aggregate preserved-C and nutrients in region mountain agricultural soils 1 year after its planting

[J]. Land Degradation and Development, 2017288): 2408-2417.

[本文引用: 1]

Cui HuYang OuWang Lixiaet al.

Distribution and release of phosphorus fractions associated with soil aggregate structure in restored wetlands

[J]. Chemosphere, 2019223319-329.

[本文引用: 1]

Chen QiujieZhang NannanZhong Boet al.

Change of soil nutrient and aggregate structure during the desertification process of grassland in Zoige

[J]. Ecological Science, 2019384): 13-20.

[本文引用: 1]

陈秋捷张楠楠仲波.

若尔盖高寒草地退化沙化过程中土壤养分与团聚体结构的变化特征

[J]. 生态科学, 2019384): 13-20.

[本文引用: 1]

/