Effects of soil moisture on cotton root length density and yield under drip irrigation with plastic mulch in Aksu Oasis farmland

Effects of soil moisture on cotton root length density (total root length per unit soil volume) and yield under drip irrigation with plastic mulch were studied through field experiments. The results indicate that spatial distributions of root length density of cotton under various water treatments were basically similar. Horizontally, both root length densities of cotton in wide and narrow rows were similar, and higher than that between mulches. Vertically, root length density of cotton decreased with increasing soil depth. The distribution of root length density is different under different irrigation treatments. In conditions of over-irrigation, the root length density of cotton between mulches would increase. However, it would decrease in both the wide rows and narrow rows. The mean root length density of cotton increased with increasing irrigation water. Water stress caused the root length density to increase in lower soil layers. There is a significant correlation between root length density and yields of cotton at the flower-boll and wadding stages. The regression between irrigation amount and yield of cotton can be expressed as y = -0.0026x2+18.015x-24845 (R2 = 0.959). It showed that the irrigation volume of 3,464.4 m3/hm2 led to op-timal root length density. The yield of cotton was 6,360 .8 kg/hm2 under that amount of irrigation.

Root length density distribution and associated soil water dynamics for tomato plants under furrow irrigation in a solar greenhouse

Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in water-limited regions. The objectives of this study are to analyze root length density distribution and to explore soil water dynamics by simulating soil water content using a HYDRUS-2D model with consideration of root water uptake for furrow irrigated tomato plants in a solar greenhouse in Northwest China. Soil water contents were also in-situ observed by the ECH_2O sensors from 4 June to 19 June and from 21 June to 4 July, 2012. Results showed that the root length density of tomato plants was concentrated in the 0–50 cm soil layers, and radiated 0–18 cm toward the furrow and 0–30 cm along the bed axis. Soil water content values simulated by the HYDRUS-2D model agreed well with those observed by the ECH_2O sensors, with regression coefficient of 0.988, coefficient of determination of 0.89, and index of agreement of 0.97. The HYDRUS-2D model with the calibrated parameters was then applied to explore the optimal irrigation scheduling. Infrequent irrigation with a large amount of water for each irrigation event could result in 10%–18% of the irrigation water losses. Thus we recommend high irrigation frequency with a low amount of water for each irrigation event in greenhouses for arid region. The maximum high irrigation amount and the suitable irrigation interval required to avoid plant water stress and drainage water were 34 mm and 6 days, respectively, for given daily average transpiration rate of 4.0 mm/d. To sum up, the HYDRUS-2D model with consideration of root water uptake can be used to improve irrigation scheduling for furrow irrigated tomato plants in greenhouses in arid regions.

Flavonoid scutellarin positively regulates root length through NUTCRACKER

Exploring approaches to regulate meristem is of special importance and broad interest.In this study,we found that the flavonoid scutellarin,which has a 6-hydroxyl and a 7-glucoside,increased root length through the transcription factor NUTCRACKER(NUC).This root lengthening disappeared in NUCknockout and reappeared in NUC-rescue plants.Scutellarin induced NUC expression and promoted the division of cortex/endodermal initials.In contrast,naringenin,which has same chemical backbone but without 6-hydroxyl and with 7-hydroxyl group,showed the opposite or no effects.Our results demonstrate that scutellarin promotes root length through NUC-mediated regulatory pathways and reveal that flavonoids with and without the 6-hydroxyl and 7-glucoside have positive and negative effects on meristem size,respectively。

Root Length Density in Maize/Cowpea Intercropping under a Basin Tillage System in a Semi-Arid Area of Zimbabwe

A study to assess the effect of intercropping maize (Zea mays L.) and cowpea (Vigna unguiculata L.) within the same basin or outside the basin on root length density (RLD) was conducted at the International Crop Research Institute for Semi-Arid Tropics (ICRISAT) Matopos Research Station from December 2009 to April 2010. The experiment was laid out in a Randomised Complete Block Design (RCBD) with four treatments replicated four times namely;sole maize, sole cowpea, maize-cowpea intercrop with cowpea and maize planted within the same basin and maize-cowpea intercrop with cowpea planted 20 cm outside the maize basin. There was significant difference (P < 0.001) in RLD, grain yield and stover yield. Maize-cowpea intercropped within the same basin achieved higher RLD, grain yield and stover yield than cowpea that was intercropped outside the basin and the sole crops. The land equivalent ratio (LER) in both intercrop designs showed that intercropping had better grain yield performance when compared to sole cropping. It can be concluded that intercropping maize and cowpeas within the same basin can result in an environment around the crop achieving higher RLD which translates to better grain yield compared to the sole cropping and intercropping cowpeas outside the basin.

Seasonal dynamics of fine root biomass, root length density, specific root length, and soil resource availability in a Larix gmelinii plantation

Fine root turnover is a major pathway for carbon and nutrient cycling in terrestrial ecosystems and is most likely sensitive to many global change factors.Despite the importance of fine root turnover in plant C allocation and nutrient cycling dynamics and the tremendous research efforts in the past,our understanding of it remains limited.This is because the dynamics processes associated with soil resources availability are still poorly understood.Soil moisture,temperature,and available nitrogen are the most important soil characteristics that impact fine root growth and mortality at both the individual root branch and at the ecosystem level.In temperate forest ecosystems,seasonal changes of soil resource availability will alter the pattern of carbon allocation to belowground.Therefore,fine root biomass,root length density(RLD)and specific root length(SRL)vary during the growing season.Studying seasonal changes of fine root biomass,RLD,and SRL associated with soil resource availability will help us understand the mechanistic controls of carbon to fine root longevity and turnover.The objective of this study was to understand whether seasonal variations of fine root biomass,RLD and SRL were associated with soil resource availability,such as moisture,temperature,and nitrogen,and to understand how these soil components impact fine root dynamics in Larix gmelinii plantation.We used a soil coring method to obtain fine root samples(≤2 mm in diameter)every month from May to October in 2002 from a 17-year-old L.gmelinii plantation in Maoershan Experiment Station,Northeast Forestry University,China.Seventy-two soil cores(inside diameter 60 mm;depth intervals:0-10 cm,10-20 cm,20-30 cm)were sampled randomly from three replicates 25 m×30 m plots to estimate fine root biomass(live and dead),and calculate RLD and SRL.Soil moisture,temperature,and nitrogen(ammonia and nitrates)at three depth intervals were also analyzed in these plots.Results showed that the average standing fine root biomass(live and dead)was 189.1 g·m^(-2)·a^(-1),50%(95.4 g·m^(-2)·a^(-1))in the surface soil layer(0-10 cm),33%(61.5 g·m^(-2)·a^(-1)),17%(32.2 g·m^(-2)·a^(-1))in the middle(10-20 cm)and deep layer(20-30cm),respectively.Live and dead fine root biomass was the highest from May to July and in September,but lower in August and October.The live fine root biomass decreased and dead biomass increased during the growing season.Mean RLD(7,411.56 m·m^(-3)·a^(-1))and SRL(10.83 m·g^(-1)·a^(-1))in the surface layer were higher than RLD(1474.68 m·m^(-3)·a^(-1))and SRL(8.56 m·g^(-1)·a^(-1))in the deep soil layer.RLD and SRL in May were the highest(10621.45 m·m^(-3) and 14.83m·g^(-1))compared with those in the other months,and RLD was the lowest in September(2198.20 m·m^(-3))and SRL in October(3.77 m·g^(-1)).Seasonal dynamics of fine root biomass,RLD,and SRL showed a close relationship with changes in soil moisture,temperature,and nitrogen availability.To a lesser extent,the temperature could be determined by regression analysis.Fine roots in the upper soil layer have a function of absorbing moisture and nutrients,while the main function of deeper soil may be moisture uptake rather than nutrient acquisition.Therefore,carbon allocation to roots in the upper soil layer and deeper soil layer was different.Multiple regression analysis showed that variation in soil resource availability could explain 71-73%of the seasonal variation of RLD and SRL and 58%of the variation in fine root biomass.These results suggested a greater metabolic activity of fine roots living in soil with higher resource availability,which resulted in an increased allocation of carbohydrate to these roots,but a lower allocation of carbohydrate to those in soil with lower resource availability.

Freeze-thaw process induced by increased precipitation affects root growth of alpine steppe on the Tibetan Plateau

The response of vegetation productivity to precipitation is becoming a worldwide concern.Most reports on responses of vegetation to precipitation trends are based on the growth season.In the soil freeze/thaw process,the soil water phase and heat transport change can affect root growth,especially during the thawing process in early spring.A field experiment with increased precipitation(control,increased 25%and increased 50%)was conducted to measure the effects of soil water in early spring on above-and below-ground productivity in an alpine steppe over two growing seasons from June 2017 to September 2018.The increased 50%treatment significantly increased the soil moisture at the 10 cm depth,there was no difference in soil moisture between the increased 25%treatment and the control in the growing season,which was not consistent in the freeze/thaw process.Increased soil moisture during the non-growing season retarded root growth.Increased precipitation in the freezing-thawing period can partially offset the difference between the control and increased precipitation plots in both above-and below-ground biomass.

Determination of the Root Canal Length of Teeth of Bantu Patients Attending the Teaching Hospital of Kinshasa University

Background: There is paucity of literature on the determination of the root canal length of Bantu subjects in dental professional practicing in Africa and Democratic Republic of Congo in particular. Aims: The aim of the present study was to determine the root canal length of teeth of Bantu patients extracts attending the Teaching Hospital of Kinshasa University. Methods and Material: Prospective cross-sectional study was carried out in the service of Conservative Dentistry. The patients suffering with pulpitis of permanent teeth which were selected for root canal treatment during the period of January 2014 to December 2016 were included. All patients whose main root canals were inaccessible, teeth carrying prosthesis, teeth with large coronal decay, teeth having periapical periodontitis, supernumerary teeth, wisdom and primary teeth were excluded. Results: The upper canines presented some significant longer canals compared to the lower canine (23.4 ± 2.3 mm and 21.6 ± 1.8 mm). Palatal canals of the first and second molar were respectively longer as compared to the superior teeth canals (21.5 ± 1 mm, 21.3 ± 2 mm). The distal canals of the first and second molar were the longest in the mandibular arch respectively measuring 20.7 ± 2.0 mm and 21.5 ± 1.7 mm. Conclusion: Data obtained from Bantu patients show slightly shorter roots compared to some European populations, but longer than some Asian populations.

Tooth anatomy risk factors influencing root canal working length accessibility

The aim of this study was to analyze the specific influence of root canal anatomy on the accessibility of working length during root canal therapy. Four hundred seventy-six root canal therapy cases （amounting to a total of 1 005 root canals） were examined. The anatomy risk factors assessed in each case included： tooth type （tooth location）, root canal curvature, and root canal calcification, as well as endodontic retreatment. The investigation examined the correlation between each of these anatomic factors and the working length, with statistical analysis consisting of Chi-square tests and multiple logistic regression analysis. In an independent factor analysis, tooth type （tooth iocation）, root canal curvature, canal calcification, and endodontic retreatment were determined to be the primary risk factors. In a multiple-factor regression model, root curvature and canal calcification were found to most significantly influence root canal working length accessibility （P〈0.05）. Root canal anatomy increases the difficulty of root canal preparation. Appropriate consideration of tooth anatomy will assist in accurate determination of preparation difficulty before instrumentation. This study alerts clinical therapists to anatomical factors influencing the working length accessibility, and allows for a direct estimate of success rate given in situ measurements of tooth factors during the root canal treatment procedure.

口腔临床诊疗中数字牙片影像技术的应用价值

目的探讨口腔临床诊疗中数字牙片影像技术的应用价值。方法选择2022年1月至2023年5月期间在本院口腔科就诊且需要拔牙治疗的50例正畸患者作为研究对象。患者在治疗前,完成数字化牙片摄影和传统牙片摄影。记录投照上、下颌牙齿X线倾斜的垂直平均角度,并统计牙齿根尖片的曝光时间,对比两种摄影技术对牙齿长度的测量结果。结果传统牙片摄影时,上颌和下颌切牙位、单尖牙、双尖牙位、第一磨牙位、第二及三磨牙位(足侧倾斜)选择投射角度低于数字化牙片摄影(P<0.05)。数字化牙片摄影投照上颌和下颌切牙位、单尖牙位、双尖牙位、第三磨牙位及第一、二磨牙位牙齿根尖片的曝光时间低于传统牙片摄影(P<0.05)。数字化牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果与游标卡尺测量结果相比,差异无统计学意义(P>0.05);传统牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果低于游标卡尺测量结果,差异具有统计学意义(P<0.05);以游标卡尺测量结果为依据,数字化牙片摄影和传统牙片摄影对待拔除牙齿单根、双根颊和双根腭测量结果相比,差异具有统计学意义(P<0.05)。结论数字牙片影像技术投照条件宽容度相对较大,投射时曝光时间短,对牙齿根尖的测量准确度较高,便于细致观察牙齿,应用于口腔临床诊疗的价值较高。

丁香酸对不同品种烟草苗期根系生长的影响

为探究最新发现的植物源生物硝化抑制剂丁香酸对烟草品种K326和云烟85苗期根系生长的影响,通过基质培养试验,设置0、10、25、50、100、200 μmol/L 6个丁香酸浓度,研究了不同浓度丁香酸在不同时间(3 d和5 d)对K326和云烟85主根伸长量和一级侧根发育的影响。结果表明:与对照(0 μmol/L)相比,25~100 μmol/L丁香酸能促进K326主根伸长,在3 d时促进率为13.33%~30.67%,在5 d时促进率降为8.54%~22.55%,最适浓度为50 μmol/L;10~50 μmol/L丁香酸促进云烟85主根伸长,在3 d时促进率为7.81%~18.75%,在5 d时促进率维持在4.10%~10.66%,最佳促进浓度25 μmol/L;丁香酸对两个烟草品种主根伸长的促进效果均为3 d优于5 d。在侧根发育方面,低浓度丁香酸能显著促进K326和云烟85一级侧根数,两个品种促进侧根发育的最适浓度均为25 μmol/L。相关性分析表明,丁香酸处理下两个烟草品种苗期的主根伸长变化率与侧根数变化率呈显著正相关。可见,适宜浓度的丁香酸对两个典型烟草品种苗期主根增长和侧根发育均为促进效应。生物硝化抑制剂丁香酸具有促进烟草根系生长的潜力,为研发烤烟新型专用肥提供了理论依据。

不同草本植物根系对土壤渗透性的影响

[目的]揭示当地排土场不同草本植物根系对土壤渗透性的影响,阐明预测草本植物根系提升土壤渗透性的最优指标,并得出草本植物根系提升土壤渗透性的最佳径级,为排土场生态修复植物选择提供重要依据。[方法]以海州露天矿排土场为研究地点,以轴根型紫花地丁、根蘖型苦荬菜和根茎型水麦冬为研究对象,采用图片像素换算法量化3种根系在不同土层深度范围内的根系分布特征;并结合渗透试验获取3种草本植物原状根土复合体的渗透参数,进而探究了根土复合体根系分布参数与渗透参数的关系。[结果]3种草本植物均能提升土壤的渗透性能,轴根型、根茎型和根蘖型根土复合体的初始入渗率、稳渗率、平均渗透速率、渗透总量相较于素土分别提升82.23%~254.99%,85.59%~307.63%,72.02%~325.91%,62.93%~246.98%。3种草本植物根系的根长密度和根表面积密度与根土复合体的渗透参数均呈现线性相关,根表面积密度的相关性强于根长密度。3种根系对土壤渗透性的增强作用主要归功于0.5 mm<D≤1.5 mm径级,它们均存在提升土壤渗透性的最佳径级。[结论]草本植物根系能够提升土壤渗透性,根表面积密度是最佳预测指标,且不同根系均存在最佳径级。

Root ZX和Raypex 5两种根管长度测量仪在老年人根管治疗中的应用

比较RootZX和Raypex5两种根管长度测量仪测量老年人后牙根管工作长度(root working length,RWL)的准确性;发现二者测量准确、简便,准确性差异没有显著性;不同牙髓状态时的测量结果差异亦无显著性。

Effects of plant roots on soil preferential pathways and soil matrix in forest ecosystems

To characterize effects of plant roots on preferential flow（PF）,we measured root length density（RLD）and root biomass（RB） in Jiufeng National Forest Park,Beijing,China.Comparisons were made for RLD and RB between soil preferential pathways and soil matrices.RLD and RB declined with the increasing soil depth（0–10,10–20,20–30,30–40,40–50,50–60 cm） in all experimental plots.RLD was greater in soil preferential pathways than in the surrounding soil matrix and was 69.5,75.0 and72.2 % for plant roots of diameter（d） ／1,1 ／ d ／ 3 and3 ／ d ／ 5 mm,respectively.Fine root systems had the most pivotal influence on soil preferential flow in this forest ecosystem.In all experimental plots,RB content was the sum of RB from soil preferential pathways and the soil matrix in each soil depth.With respect to 6 soil depth gradient（0–10,10–20,20–30,30–40,40–50,50–60 cm） in each plot,the number of soil depth gradient that RB content was greater in soil preferential pathways than in the soil matrix was characterized,and the proportion was68.2 % in all plots.

岷江上游干旱河谷地区油松和岷江柏细根生物量和根长密度

了解岷江上游干旱河谷地区12年生油松(Pinus tabulaeformis)和岷江柏(Cupressus chengiana)人工林细根(直径≤2 mm)生物量和根长密度在土层中的垂直分布状况,分析不同土层中细根系统的碳分配策略,为岷江上游干旱河谷地区植被恢复提供理论依据。以岷江上游干旱河谷地区的油松和岷江柏人工林为研究对象,采用土钻法进行取样,测定2种林分不同土层深度(h)(0 cm<h≤15 cm和15 cm<h≤30 cm)中吸收根(1~3级)和运输根(≥4级的细根)生物量和根长密度,以及吸收根占总细根生物量和根长密度比例。结果显示:油松和岷江柏吸收根生物量和根长密度在0 cm<h≤15 cm土层均显著高于15 cm<h≤30 cm土层,而运输根生物量和根长密度在土层间差异均不显著;油松和岷江柏吸收根占总细根生物量和根长密度比例在0 cm<h≤15 cm土层均显著高于15 cm<h≤30 cm土层(P<0.05);岷江柏吸收根占总细根生物量和根长密度比例在2个土层中均显著高于油松(P<0.05)。研究结果表明,在养分有效性最高的土壤表层,油松和岷江柏细根系统内将更多的碳分配到吸收根。

Root ZX根管测量仪与三联法对根管充填质量的比较研究

目的比较研究Root ZX根管长度测量仪与三联法对根管充填质量的影响。方法随机选择需行根管治疗术的单根管恒前牙、双尖牙320颗,分为两组,在根管预备前分别应用Root ZX根管测量仪与三联法测量根管长度,以此长度进行预备和充填,然后摄牙片,比较其准确率。结果两种方法充填根管X线片结果差异明显,电测组适充率为91.41%,三联法组适充率为68.71%。电测组明显优于三联法组(P<0.05)。结论Root ZX测量仪是一种安全可靠、准确率高的根管长度测量仪。

体内不同冲洗液对ROOT ZX电测仪准确性的影响

目的:体内评价不同冲洗液对Root ZX根尖电测仪测量结果的影响。方法:150颗需根管治疗的单根管牙随机分为5组,开髓,冠向敞开后同时去除根管内牙髓后分别以3%H2O2、17%EDTA、0.5%NaOCl、生理盐水冲洗根管3次,最后一次保留冲洗液,进行根管测量。空白组为0.5%次氯酸钠和生理盐水交替冲洗后的干燥根管。各组测量3次的平均值与X片确定的根管长度值以单因素方差分析(ANOVA)分析各组间差异。结果:各组根管长度测量值与实际根管长度无显著性差异,单因素方差分析显示各组间测量值无显著性差异。结论:ROOT ZX根尖定位仪能准确测量根管长度,且不受根管内冲洗液的影响。

Correlation of Leaf and Root Senescence During Ripening in Dry Seeded and Transplanted Rice

Dry seeding is a resource-saving rice establishment method. With an equivalent yield, dry seeded flooded rice （DSR） has been considered as a replacement for traditional transplanted flooded rice （TFR）. However, the differences in leaf and root senescence during grain filling between DSR and TFR were seldom identified. In this study, the root length, root tip number and leaf senescence of rice varieties Huanghuazhan and Yangliangyou 6 during ripening were compared between DSR and TFR. Results showed that top three leaves in DSR had the characteristics of relatively lower SPAD value, lower N content and premature leaf senescence. In addition, both the total root length and total root tip number of DSR were significantly lower than those of TFR. In conclusion, premature and quick leaf senescence was related with inadequate root length and root tip number during ripening, which might result from the deficiency of nitrogen supply in DSR. Techniques on improving leaf nitrogen status and delaying the leaf senescence during grain-filling in DSR should be developed in future researches.

Response of root traits of Reaumuria soongorica and Salsola passerina to facilitation

C3 plant Reaumuria soongorica and C4 plant Salsola passerina are super xerophytes and coexist in a mixed community in either isolated or associated growth, and interspecific facilitation occurs in associated growth. In the present study, the root traits including root distribution, root length（RL）, root surface area（RSA）, root weight（RW） and specific root length（SRL） of both species in two growth forms were investigated to clarify their response to facilitation in associated growth. Six isolated plants of each species, as well as six associated plants similar in size and development were selected during the plant growing season, and their roots were excavated at 0–10, 10–20, 20–30, 30–40 and 40–50 cm soil depths at the end of the growing season. All the roots of each plant were separated into the two categories of fine roots（2 mm diameter） and coarse roots（≥2 mm diameter）. Root traits such as RL and RSA in the fine and coarse roots were obtained by the root analyzing system WinRHIZO. Most of the coarse roots in R. soongorica and S. passerina were distributed in the top 10 cm of the soil in both growth forms, whereas the fine roots of the two plant species were found mainly in the 10–20 and 20–30 cm soil depths in isolated growth, respectively. However, the fine roots of both species were mostly overlapped in 10–20 cm soil depth in associated growth. The root/canopy ratios of both species reduced, whereas the ratios of their fine roots to coarse roots in RL increased, and both species had an increased SRL in the fine roots in associated growth. In addition, there was the increase in RL of fine roots and content of root N for S. passerina in associated growth. Taken together, the root growth of S. passerina was facilitated for water and nutrient exploration under the interaction of the overlapped roots in both species in associated growth, and higher SRL allowed both species to more effectively adapt to the infertile soil in the desert ecosystem.

Analysis of root fractal characteristics in remote areas of the Taklimakan desert,China

Fractal geometry is a potential new approach to analyze the root architecture, which may offer improved ways to quantify and summarize root system complexity as well as yield ecological and physiological insights into the functional relevance of specific architectural patterns. Fractal analysis is a sensitive measure of root branching intensity and fractal dimension expresses the ＂space filling＂ properties of a structure. The objective of this study was to find out the fractal characteristics of root systems in a remote area of the Taklimakan desert in China. The entire root system of two naturally occurring species were excavated and exposed with shov- els in 2007. The species were Tamarix taklamakanensis and Calligonum roborovskii. A one-factorial ANOVA with species as factor showed statistically a highly significant difference in fractal dimensions, indicating differences in their pattern of root branching. There was no relationship between root diameter and two parameters of fractal root models a and q, representing general characteris- tics of root systems, for either species （a： the ratio of the sum of root cross-sectional areas after a branching to the cross-sectional area before root division; q： the distribution of the cross-sectional areas after branching）. We have found significant linear relation- ships between the diameter after branching and root length and biomass respectively, because of the self-similarity of root branching. Branching rules are the same for roots of all sizes and lengths. Root biomass for the root systems of entire trees can be estimated by measuring the diameter of each root at the base of the trunk or the diameter after branching. We have shown that the diameter of each root at the base of the trunk and the diameter after branching are effective indices that can be measured easily in order to estimate the root lengths, biomass and other parameters of root architecture.

基于微根管技术的不同耕作方式下玉米根系生长动态监测

为探究东北黑土区从传统耕作转变为保护性耕作后玉米根系的变化特征,评价保护性耕作的适宜性及微根管技术的可靠性,采用微根管技术对免耕(NT)、旋耕(RT)和条耕(ST)等3种耕作方式下玉米根系进行原位监测,并与传统土钻法进行比较。结果表明,耕作方式对根系形态指标的影响随生育期进行逐渐由表层向深层土壤延伸,影响指标也由少到多。不同耕作方式下超过65%的玉米根系集中分布在0~30 cm土层。苗期以后,ST处理总根长、根长密度明显高于其他处理,但仅在成熟期时差异显著(P<0.05)。耕作方式对根系构型与分布的调控主要通过影响土壤剖面含水量和穿透阻力等来实现。整个土壤剖面ST处理平均含水量最高。0~15 cm土层NT处理土壤穿透阻力显著高于ST和RT处理,最高为1558.20 kPa,15~45 cm土层各处理土壤穿透阻力较为接近。微根管法与土钻法测得的根长密度相对误差基本在10.0%以内。本试验条件下,耕作方式转变可以显著影响根表面积、体积、直径、根长密度等根系特征,土壤水分状况和穿透阻力对作物根系生长具有较大影响。利用微根管法获得的根长密度与土钻法所得结果具有较好的相关性,2种方法相结合在今后作物根系生长动态监测中具有重要推广应用价值。