Tamarix chinensis Lour inhibits chronic ethanol-induced liver injury in mice

BACKGROUND Tamarix chinensis Lour(TCL)is a shrub that usually grows in arid or semiarid desert areas and saline-alkali fields.It is a traditional Chinese herbal medicine with hepatoprotective,antioxidant,antibacterial,and antitumor activities.AIM To investigate the possible protective effects of TCL against liver injury induced by chronic ethanol intake.METHODS C57BL/6J male mice were fed a Lieber-DeCarli lipid diet containing alcohol and received(by gavage)a water-alcohol extract(80%)of TCL(100 and 200 mg/kg BW)or distilled water for 4 wk.After euthanasia,liver tissues were observed histologically with hematoxylin and eosin staining and Oil red O staining,and the levels of alanine aminotransferase,aspartate transaminase,hepatic lipids,reactive oxygen species,malondialdehyde,and superoxide dismutase were measured.In addition,expression of the NOD-like receptor family,pyrin domain-containing 3(NLRP3)inflammasome and downstream proinflammatory cytokines were determined.RESULTS Compared with the ethanol group,mice in the TCL-treated group(200 mg/kg)had significantly lower serum levels of alanine aminotransferase(mean,34.1 IU/L vs 45.3 IU/L,P<0.01)and aspartate transaminase(mean,89.6 IU/L vs 115.7 IU/L,P<0.01),as well as marked reduction of hepatic tissue reactive oxygen species(decreased by 27.5%,P<0.01)and malondialdehyde(decreased by 76.6%,P<0.01)levels,with a significant increase of superoxide dismutase(Increased by 73.2%,P<0.01).Expression of the NLRP3 inflammasome and its downstream cytokines[interleukin(IL)-1β,tumor necrosis factor-α,and IL-6],and recruitment of natural killer T cells to the liver,were reduced in the TCLtreated incubation with a Lieber-DeCaril ethanol lipid diet group.CONCLUSION These findings suggest that a TCL extract(200 mg/kg)protects against chronic ethanol-induced liver injury,probably by inhibiting the NLRP3-caspase-1-IL-1βsignaling pathway and suppressing oxidative stress.

Effects of water and salt for groundwater-soil systems on root growth and architecture of Tamarix chinensis in the Yellow River Delta,China

To test the patterns of the root morphology and architecture indexes of Tamarix chinensis in response to water and salt changes in the two media of the groundwater and soil,three-year-old T.chinensis seedlings were chosen as the research object.Groundwater with four salinity levels was created,and three groundwater level(GL)were applied for each salinity treatment to measure the root growth and architecture indexes.In the fresh water and brackish water treatments,the topological index(TI)of the T.chinensis roots was close to 0.5,and the root architecture was close to a dichotomous branching pattern.In the saline water and saltwater treatments,the TI of the T.chinensis roots was large and close to 1.0,and the root architecture was close to a herringbone-like branching pattern.Under different GLs and salinities,the total root length was significantly greater than the internal link length,the external link length was greater than the internal link length,and the root system showed an outward expansion strategy.The treatment with fresh water and a GL of 1.5 m was the most suitable for T.chinensis root growth,while the root growth of T.chinensis was the worst in the treatment with saline water and a GL of 0.3 m.T.chinensis can adapt to the changes in soil water and salt by regulating the growth and morphological characteristics of the root system.T.chinensis can adapt to high-salt environments by reducing its root branching and to water deficiencies by expanding the distribution and absorption area of the root system.

埃及中国柽柳(Tamarix chinensis)解剖结构研究

中国柽柳(Tamarix chinensis)属于盐生植物。本文采用石蜡切片法对于分布于埃及红海岸的中国柽柳的茎、叶的解剖结构进行了观察和对比分析。结果表明:埃及中国柽柳具有显著的盐生植物结构特征,突出表现在:叶的表皮细胞外覆有发达的角质层,气孔下陷,形成气孔室;茎、叶的表皮上有盐腺;茎、叶的表皮内侧为栅栏组织细胞层,细胞内有较多的叶绿体。

Microbial diversity in the saline-alkali soil of a coastal Tamarix chinensis woodland at Bohai Bay, China

Soil salinization or alkalization is a form of soil desertification. Coastal saline-alkali soil represents a type of desert and a key system in the network of ecosystems at the continent-ocean interface. Tamarix chinensis is a drought-tolerant plant that is widely distributed in the coastal saline-alkali soil of Bohai Bay, China. In this study, we used 454 pyrosequencing techniques to investigate the characteristics and distribution of the microbial diversity in coastal saline-alkali soil of the T. chinensis woodland at Bohai Bay. A total of 20,315 sequences were obtained, representing 19 known bacterial phyla and a large proportion of unclassified bacteria at the phylum level. Proteobacteria, Acidobacteria and Actinobacteria were the predominant phyla. The coverage of T. chinensis affected the microbial composition. At the phylum level, the relative abundance of y-Proteobacteria and Bacteroidetes decreased whereas Actinobacteria increased with the increasing coverage of T. chinensis. At the genus level, the proportions of Steroidobacter, Lechevalieria, Gp3 and Gp4 decreased with the increase of the vegetation coverage whereas the proportion of Nocardioides increased. A cluster analysis showed that the existing T. chinensis changed the niches for the microorganisms in the coastal saline-alkali soil, which caused changes in the microbial community. The analysis also distinguished the microbial community structure of the marginal area from those of the dense area and sparse area. Furthermore, the results also indicated that the distance to the seashore line could also affect certain groups of soil bacteria in this coastal saline-alkali soil, such as the family Cryomorphaceae and class Flavobacteria, whose population decreased as the distance increased. In addition, the seawater and temperature could be the driving factors that affected the changes.

The anti-tubercular activity of Melia azedarach L. and Lobelia chinensis Lour. and their potential as effective anti-Mycobacterium tuberculosis candidate agents

Objective: To evaluate the anti-mycobacterial activity of Melia azedarach L.(M. azedarach) and Lobelia chinensis Lour.(L. chinensis) extracts against the growth of Mycobacterium tuberculosis(M. tuberculosis).Methods: The anti-M. tuberculosis activity of M. azedarach and L. chinensis extracts were evaluated using different indicator methods such as resazurin microtiter assay(REMA) and mycobacteria growth indicator tube(MGIT) 960 system assay. The M. tuberculosis was incubated with various concentrations(50–800 mg/m L) of the extracts for 5 days in the REMA, and for 4 weeks in MGIT 960 system assay.Results: M. azedarach and L. chinensis extracts showed their anti-M. tuberculosis activity by strongly inhibiting the growth of M. tuberculosis in a concentration-dependent manner in the REMA and the MGIT 960 system assay. Particularly, the methanol extract of M. azedarach and n-hexane extract of L. chinensis consistently exhibited their effects by effectively inhibiting the growth of M. tuberculosis in MGIT 960 system for 4 weeks with a single-treatment, indicating higher anti-M. tuberculosis activity than other extracts,and their minimum inhibitory concentrations were measured as 400 mg/m L and 800 mg/m L, respectively.Conclusions: These results demonstrate that M. azedarach and L. chinensis extracts not only have unique anti-M. tuberculosis activity, but also induce the selective antiM. tuberculosis effects by consistently inhibiting or blocking the growth of M. tuberculosis through a new pharmacological action. Therefore, this study suggests the potential of them as effective candidate agents of next-generation for developing a new anti-tuberculosis drug, as well as the advantage for utilizing traditional medicinal plants as one of effective strategies against tuberculosis.

Effects of 1-aminobenzotriazole on the growth and physiological characteristics of Tamarix chinensis cuttings under salt stress

vegetation restoration is a main ecological remediation technology for greening saline and alkaline soils.The objectives of this study were to determine the effect of1-aminobenzotriazole(ABT-1) on the growth and physiology of Tamarix chinensis under salt stress and to determine a suitable ABT-1 concentration and soil salinity(Sc) for propagating T.chihehsis-cuttings.Cuttings were soaked in water and ABT-1 solutions at three concentrations(50,100,and 200 mg L^(-1)) and propagated in pots containing four soil salinity levels,mild(0.3%),moderate(0.6%),and severe(0.9% and 1.2%),and compared with a control.The cuttings were measured to determine growth indices and physiological and biochemical indices(e.g.,chlorophyll content,superoxide dismutase activity,peroxidase activity,and malondialdehyde content).ABT-1 was effective in improving survival,growth,and physiological processes of cuttings under salt stress.However,there was a threshold effect when using ABT-1 to facilitate propagation under salt stress.ABT-1 effects were insignificant when applied at low concentrations(<100 mg L^(-1)).At a high concentration(> 100 mg L^(-1)),ABT-1 limited growth and physiological activities.Under a salt stress level(Sc ≤0.9%),ABT applied at a 100 mg L^(-1)concentration increased chlorophyll content and superoxide dismutase and peroxidase activities in the leaves and reduced malondialdehyde accumulation and membrane lipid peroxidation effects.As a result,ABT-1 enhanced the resistance of T.chinensis to salt stress.However,under high salt stress(>0.9%) and ABT-1 concentration(> 100 mg L^(-1)),the physiological regulatory ability of T.chinensis seedlings weakened.T.chinensis grew well at a salt stress ≤0.9% and ABT ≤100 mg L^(-1) and exhibited relatively high physiological regulatory ability and high salt adaptability.

Preliminary assessment of two non-destructive instrumental techniques for quality evaluation of Lobelia chinensis Lour.

Two non-destructive instrumental methods, infrared spectroscopy （IR） and X-ray diffraction （XRD）, were studied for qualiW evaluation of Lobelia chinensis Lour. （L chinensis）. We obtained the IR spectra and XRD patterns of L chinensis collected from different sources. The similarity of samples was analyzed by cal- culating the cosine coefficient. The cosine values were in the range of 0.83-0.90, indicating that the main components ofL chinensis samples are similar. Sample L1 and L6 showed a slightly lower similarity than that of L2, L3, L4, L5 detected by the two methods, which revealed that IR and XRD methods exhibited analogous detection ability for quality evaluation of L. chinensis. The two methods could be highly re- commended as simple and rapid detection means for quality evaluation of L. chinensis.

Simulating Potential Distribution of Tamarix chinensis in Yellow River Delta by Generalized Additive Models

There are typical ecosystems of littoral wetlands in the Yellow River Delta.In order to study the relationships between Tamarix chinensis and environmental variables and to predict T.chinensis potential distribution in the Yellow River Delta,641 vegetation samples and 964 soil samples were collected in the area in October of 2004,2005,2006 and 2007.The contents of soil organic matter,total phosphorus,salt,and soluble potassium were determined.Then,the analyzed data were interpolated into spatial raster data by Kriging interpolation method.Meanwhile,the digital elevation model,soil type map and landform unit map of the Yellow River Delta were also collected.Generalized Additive Models(GAMs) were employed to build species-environment model and then simulate the potential distribution of T.chinensis.The results indicated that the distribution of T.chinensis was mainly limited by soil salt content,total soil phosphorus content,soluble potassium content,soil type,landform unit,and elevation.The distribution probability of T.chinensis was produced with a lookup table generated by Grasp Module(based on GAMs) in software ArcView GIS 3.2.The AUC(Area Under Curve) value of validation and cross-validation of ROC(Receive Operating Characteristic) were both higher than 0.8,which suggested that the established model had a high precision for predicting species distribution.

Spatial Distribution of Heavy Metals in Sediments of Tamarix chinensis Wetland on the South Bank of Bohai Bay

In order to understand the spatial distribution of heavy metals in coastal wetlands,Tamarix chinensis wetlands on the south bank of Bohai Bay were selected as the research object.The content of Cr,Mn,Ni,Zn and Cu in soil was determined by sampling method in April 2018.The spatial distribution characteristics of heavy metals and causes were studied.The results showed that except for Cr,Ni and Zn,the content of other heavy metals in this area did not exceed the background value of soil environment in Shandong Province.The study area was slightly polluted by these three heavy metals.In the vertical direction,the content of Cr,Mn,Cu and Ni followed the law of surface layer>middle layer>bottom layer,while the content of Zn was higher in the bottom layer,which needed to be further studied.In the horizontal direction,the content of the five heavy metals was not significantly different according to the distance from the coastline.There was no significant difference in the content of heavy metals between rhizosphere soil and non-rhizosphere soil.There was a significant correlation between the content of heavy metal elements,except Mn,the content of heavy metals was significantly correlated with the content of soil organic matter.The content of some heavy metals was significantly correlated with the content of available phosphorus and ammonium nitrogen.

凋落物输入变化对黄河三角洲柽柳人工林土壤有机碳及其组分的影响

为探究凋落物输入变化对土壤有机碳库的影响,明确凋落物对森林生态系统土壤碳循环的作用,以黄河三角洲滨海盐碱地柽柳人工林为研究对象,通过设置添加凋落物(LA)、去除凋落物(LR)和对照(CK)3种处理方法,分析凋落物不同输入变化对土壤理化性质、土壤有机碳及其组分的影响。结果表明:凋落物添加和去除处理影响土壤理化性质的变化,与对照相比,添加凋落物降低了土壤密度和含盐量,增加了土壤含水量和养分(全氮、全磷、全钾),而去除凋落物则相反。3种处理对土壤有机碳(SOC)及其储量以及活性有机碳组分的影响一致,均表现为LA处理影响最大,LR处理影响最小,其中LA处理比CK增加了SOC质量分数及储量,但增加不显著;LR处理则显著降低了SOC质量分数及其储量,土层深度(d)0<d≤10 cm土层,LR处理比CK处理的SOC质量分数及其储量分别显著降低了34.93%、12.66%,10 cm<d≤20 cm土层,LR处理比CK处理的SOC质量分数及其储量分别显著降低了24.27%、16.13%。LA处理的土壤SOC及可溶性有机碳(DOC)、易氧化有机碳(EOC)、微生物量碳(MBC)质量分数均出现明显的表聚现象,而LR处理影响则不显著,且DOC和MBC则出现随土层深度增加而增大的趋势。土壤惰性有机碳(ROC)质量分数在不同土层间存在差异,0<d≤10 cm土层,各处理表现为LA>CK>LR,10 cm<d≤20 cm土层,各处理则表现为CK>LA>LR,而在CK和LR处理出现随土层增加而增加的趋势,偏于向土层下方积累。土壤密度(BD)与SOC及其各组分呈负相关,而土壤含水量(WC)、全氮、全磷与SOC及EOC、MBC、DOC质量分数呈极显著正相关(P<0.01)。因此,不同处理方式及不同土层深度的土壤密度、全氮质量分数和土壤含水量是影响SOC及组分变化的主要环境因子。

黄河三角洲柽柳人工林土壤微生物群落结构及多样性分析

【目的】探究黄河三角洲不同林龄柽柳人工林对土壤微生物群落结构特征及多样性的影响,对评价人工林土壤质量动态变化和后期栽培管理具有重要意义。【方法】以无林地(WLD)和3种不同林龄(TC3a、TC8a、TC12a)的柽柳人工林为研究对象,采用高通量测序技术,对土壤细菌和真菌群落结构及多样性变化进行分析。【结果】3种林龄及无林地土壤微生物数量均表现为细菌>真菌,随着林龄的增加,优势菌群未发生改变。林龄对土壤细菌和真菌群落α多样性的影响有限,其中细菌Chao1index、ACE index和Shannon指数表现为TC8a>TC3a>TC12a,而真菌Shannon指数和Simpson指数则表现为TC3a>TC8a>TC12a。细菌的群落组成数量在门、纲、目、科、属水平上与真菌存在显著差异,其中细菌的群落组成在各个分类水平上均表现为TC12a>TC8a>TC3a>WLD,而真菌则表现不规律,但均以TC3a数量最多。土壤微生物优势群落和主要群落组成基本一致,但在相对丰度上存在一定差异。其中细菌群落中变形菌门Proteobacteria和unidentified Bacteria相对丰度均超过10%,是优势菌门,而真菌群落中,子囊菌门Ascomycota的相对丰度均超过45%,是绝对优势菌门。林龄变化对土壤理化性质和微生物群落结构特征均存在一定影响,其中土壤有机碳、全氮、全磷、全钾、铵态氮、有效磷及速效钾含量随着林龄的增长而增加,且均高于WLD,而土壤含盐量则表现出相反的变化规律。冗余分析表明,不同林龄的微生物群落受养分影响明显,细菌群落中土壤全氮、铵态氮和真菌群落中盐分、有机碳、全氮、全磷,分别是影响细菌和真菌群落变化的主要环境因子。【结论】柽柳人工林调控了滨海盐碱地土壤微生物群落结构,提高了土壤微生物多样性,改善了土壤理化性质,但对林龄的响应变化不规律。

黄河三角洲湿地柽柳周边土壤的水盐耦合关系

为揭示滨海湿地植物对土壤水盐的影响机制,以黄河三角洲湿地柽柳(Tamarix chinensis Lour.)周边土壤水、盐为研究对象,分析柽柳周边土壤水盐相互影响的耦合关系。结果表明:距柽柳远近不同,土壤含水率的差异明显不同,冠下表层土壤含水率明显大于冠缘和裸地,呈现由冠下至裸地逐渐减小的趋势,尤其是柽柳西、南两侧的变化趋势最为明显;20 cm土层以上水分聚集率为冠下大于冠缘,呈现明显的“水岛”效应,而20 cm以下水分聚集率的变化则相反;土壤盐分表聚性显著,远离柽柳的裸地表层土壤含盐量较高,西、南两侧最为明显;土壤总盐与Cl^(-)、Na^(+)、Mg^(2+)3种离子相关性极显著,这些离子在近柽柳周围土壤的变化幅度及含量均较小,盐分富集率明显为冠下小于冠缘,呈现“盐谷”效应;土壤水盐耦合度在柽柳周边表现为西侧>南侧>北侧>东侧,水、盐呈显著负相关;西、南两侧较高的土壤含盐量出现在低含水率的条件下,呈现高含盐量+低含水率为高耦合度的特征,这种高耦合度情况还出现在柽柳周边的表层土壤与远离柽柳的裸地。在柽柳的影响下,水盐耦合度呈现距柽柳由近及远逐步增大、随着土层深度的增加而逐渐减小的趋势。

红柳黄酮提取工艺优化及其抗氧化、抑菌活性初探

以红柳黄酮得率为评价指标,通过单因素实验和响应面法对红柳黄酮的提取工艺进行了优化,通过测定红柳不同部位黄酮提取物对DPPH自由基的清除率评价了其抗氧化活性,并考察了其对金黄色葡萄球菌、大肠杆菌、白色念珠菌的抑菌活性。结果表明,红柳黄酮的最佳提取工艺为:提取温度79.7℃、乙醇体积分数71.0%、提取时间2.19 h,在此条件下,红柳黄酮得率为5.24 mg·g^(-1);红柳不同部位黄酮提取物对DPPH自由基均有较强的清除能力;红柳不同部位黄酮提取物对金黄色葡萄球菌、大肠杆菌和白色念珠菌均有一定的抑菌活性。

柽柳再生和转化体系的建立及瞬时转化TcSYP121基因功能分析

【目的】建立柽柳再生及遗传转化体系并分析瞬时转化柳树突触融合蛋白(TcSYP121)基因功能,为筛选柽柳分子抗性育种候选基因及盐碱土的改良和生态修复提供理论参考。【方法】通过单因素筛选最佳外植体、消毒处理、各阶段(初代、分化、增殖和生根)的培养基类型及激素浓度建立柽柳再生体系;通过正交试验分析影响转化体系的4个因素(预培养时间、侵染时间、共培养时间和农杆菌浓度);通过PCR扩增及电泳结果验证柽柳转化体系;瞬时转化TcSYP121基因获得过表达植株(OE)和病毒诱导的基因沉默植株(VI),进行表型观测、植物超氧阴离子染色液(NBT)和二氨基联苯胺法(DAB)染色并测定盐腺直径和盐腺密度、叶绿素含量、超氧化物酶(SOD)活性、过氧化物酶(POD)活性及TcSYP121基因相对表达量,分析TcSYP121基因的功能。【结果】最优外植体为柽柳嫩茎段,最适宜次氯酸钠(NaClO)消毒浓度为5%,最佳消毒时间为5 min,最适合的初代培养基为MS培养基,最佳分化培养基为MS+1.0mg/L6-BA+0.1mg/LNAA,最佳增殖培养基为MS+1.5mg/L6-BA+0.1mg/LIBA,最佳生根培养基是1/2MS+0.5mg/L IBA。转化体系中正交试验结果为最佳预培养时间是2 d,最佳侵染时间是5 min,最佳共培养时间是2 d,最佳农杆菌浓度OD600为0.8,抗生素头孢霉素(Cef)浓度为300 mg/L,卡那霉素(Kan)筛选压为30 mg/L。PCR扩增及电泳结果显示,利用该遗传转化体系可获得阳性转基因植株。瞬时转化TcSYP121基因柽柳的耐盐功能分析结果显示,在盐胁迫下,VI和对照(CK)柽柳中叶绿素含量显著下降(P<0.05),而OE下降不显著(P>0.05);OE柽柳SOD和POD活性均高于VI与CK,且OE中Tc SYP121基因的相对表达量高于CK和VI。【结论】建立了柽柳的再生体系和遗传转化体系,通过对柽柳进行瞬时转化获得过表达和沉默表达柽柳,证实TcSYP121基因能够提高柽柳耐盐性。

柽柳(Tamarix chinensis)气孔导度对环境因子的响应特征和模拟

进行叶片尺度气孔行为特征、对水分利用的影响及对环境因子的响应研究,并进行叶片气孔导度的模拟,对于理解区域植被和生态系统对环境的适应机制和进行水资源管理具有重要意义。采用LI-COR6400光合作用测定系统,对柽柳(Tamarix chinensis)各项光合生理特征进行野外观测,分析了柽柳叶片气孔导度(G_(s))对环境因子的响应特征。结果表明:(1)大气相对湿度(h_(s))、光合有效辐射(PAR)和空气温度(T_(a))对柽柳叶片G_(s)影响较大,与G_(s)的相关性h_(s)(0.662)>PAR(0.613)>T_(a)(0.601)。(2)柽柳叶片G_(s)日变化趋势为先升高后降低。06:00开始,随着PAR增强和T_(a)升高,G_(s)升高,随后PAR减弱和T_(a)降低,G_(s)降低。6、7月正午T_(a)过高引起叶片气孔闭合,G_(s)最大值出现在10:00左右;8、9月G_(s)最大值出现在14:00左右。(3)在生长季末期,柽柳能够通过G_(s)的调节,实现对水分的高效利用来适应干旱的环境。(4)用经验模型(Jarvis)、半经验模型(BWB)和气孔导度机理模型(USO)模拟G_(s),模拟结果的决定系数(R^(2))、修正效率系数(MEC)和均方根误差(RMSE)分别是(0.713、0.409、0.024)、(0.482、0.309、0.158)和(0.260、0.135、0.255)。在3个模型中,Jarvis模拟R^(2)和MEC值最大且RMSE值最小,说明其模拟精度最高。

复合植物美白面膜的制备研究

本研究分别从三百草中提取黄酮,从石榴中提取有机酸和多酚,从苦参根中提取苦参碱,黄酮和多酚具有抑制酪氨酸酶活性和抗氧化的功效,有机酸具有温和去角质和亮肤的作用,苦参碱具有抗炎的作用,在研究中将其制备为复合植物美白面膜,并进行了配方设计和功效评价。制成的植物复合美白面膜对酪氨酸酶活性的抑制率为87.56%,说明植物复合美白面膜对皮肤黑色素有一定的抑制效果,具有一定美白作用。

三白草地下部分化学成分研究

目的:研究三白草科三白草属植物三白草Saururus chinensis(Lour.) Baill.地下部分的化学成分。方法:采用MCI、硅胶、Sephadex LH-20葡聚糖凝胶等多种色谱技术对三白草地下部分的丙酮提取物进行分离纯化,根据波谱数据鉴定所得化合物的结构。结果:从三白草地下部分中分离得到13个化合物,分别鉴定为:ent-4β-hydroxy-10α-ethoxyaromadendrane(1)、ent-4α-hydroxy-10β-alloaromadendranediol-10-monomethylether(2)、4β-10α-香木兰烷二醇(3)、斯巴醇(4)、meicocarpin(5)、1,4-二(3,4-二甲氧基苯基)-2,3-二甲基-1,4-丁二酮(6)、乙酰樟叶素(7)、(-)-(7R,8R)-7-O-acetylraphidecursinol B(8)、赤式-2-(4-烯丙基-2,6-二甲氧基苯氧基)-1-(3,4,5-三甲氧基苯基)-丙烷-1-醇(9)、saururin C(10)、(-)-5-exo-acefoxybornyl acetate(11)、细辛醚(12)、榄香脂素(13)。结论:其中,化合物1~4、9、11为首次从该植物中分离得到。

两种典型防护林对查干淖尔干盐湖沙化地表土壤粒度特征的影响

[目的]探究查干淖尔干盐湖附近沙化土地防护林下的土壤机械组成与生态效应,为当地的防护林建设与沙化土地治理提供科技支持。[方法]以查干淖尔干盐湖南缘沙地柽柳和梭梭两种防护林的带间、根颈和冠幅下0—20 cm的土壤为研究对象,土壤样品的机械组成用激光粒度仪测定得出,计算并分析了平均粒径、标准偏差、偏度、峰态和分形维数等粒度参数。[结果](1)研究区土壤机械组成以砂粒为主,相较于裸沙地(CK),柽柳和梭梭(带间、根颈、冠幅下)黏粉粒总含量分别增加了5.19%,0.59%,20.44%和1.53%,3.93%,4.32%,其中在冠幅下表现最为明显。(2)防护林下的土壤分选性较差,偏度均为正偏,向着尖窄方向发展;分形维数介于2.13~2.70,两种防护林冠幅下的分形维数均高于带间与根颈,与对照相比,防护林下土壤粒径整体向细粒趋势发展。(3)土壤粒度频率显示防护林各位置斜率均偏低,表明两种防护林的颗粒径级丰富度优于对照。[结论]各粒度参数及分维值反映两防护林对于当地沙化土壤有改良作用,柽柳防护林下土壤细粒化趋势更为明显。

武威市柽柳引种、选育试验

以中国柽柳(Tamarix chinensis Lour.)为对照,选取2个本地品种和4个引进品种,共计7个品种展开扦插育苗试验和引种造林试验。结果表明,中国柽柳、东柽1号、东柽2号和甘蒙柽柳的育苗成活率均在90%以上;东柽1号、东柽2号、中国柽柳的造林成活率和移栽3年后的造林保存率较高。采用综合坐标法进行分析,综合性状表现为东柽1号>东柽2号>中国柽柳>甘蒙柽柳>多花柽柳>短穗柽柳>紫枝柽柳。栽种柽柳时应当优先考虑本土树种,其环境适应能力强,存活率较高,长势更好;如果为了增加物种多样性,必须引进新品种,优先选择甘蒙柽柳、多花柽柳,可以取得比较理想的栽种效益。

甘肃柽柳耐盐性高于中国柽柳的生理基础

柽柳属植物是木本盐生植物,耐盐性强,但不同品种间耐盐能力存在差异。本研究分别对甘肃柽柳(Tamarix gansuensis H.Z.Zhang)和中国柽柳(Tamarix chinensis Lour.)进行不同浓度NaCl(0、200、400、600、800和1000 mmol/L)处理4周后,对其生长和生理指标进行了测定。结果表明,和对照相比,低浓度NaCl(200 mmol/L)明显促进了两种柽柳幼苗的生长,而高浓度NaCl明显抑制了两种柽柳幼苗的生长。高浓度NaCl明显增加了植株Na^(+)、有机渗透调节物质和活性氧(ROS)含量,降低了叶绿素含量、净光合速率和抗氧化酶活性。在相同浓度NaCl处理下,甘肃柽柳生物量、脯氨酸和可溶性糖含量、PI_(ABS)和Fv/Fm均明显高于中国柽柳,而Na^(+)和MDA含量均明显低于中国柽柳。以上结果表明甘肃柽柳比中国柽柳具有更强的耐盐性,更适于重度盐碱地的修复和改良。