Node Document

人工调控大白刺构型及其防风固沙效果研究

Artificial Regulation on Configuration of Nitraria Roborowskii and Its Effects on Windbreak and Sand Fixation

To avoid encountering 504 error when downloading big files,please take CAJ download or PDF download by chapter as your first priority.

【Author in Chinese】 王祯仪

【Supervisor】 汪季党晓宏

【Author's Information】 内蒙古农业大学, 水土保持与荒漠化防治, 2020, 博士

【Abstract in Chinese】 土地荒漠化是全球严重的生态环境问题之一,也是区域社会经济发展的瓶颈。植被建设是遏制土地荒漠化发展的有效途径,然而可用水资源短缺是荒漠化地区植被建设的限制性因子。为了提高荒漠地区植被建设的林草成活率和保存率,并解决沙区植被建设和可用水资源短缺之间的矛盾,本文通过影响植株内源激素,增加灌丛根茎比,减弱植被蒸腾损失,促进地上部分的保水力,实现人工调控荒漠灌丛构型,改变植物空间形态,从根本上提高植物对水分的利用率,进而提高沙区植被盖度和防风固沙效果。针对植物生长调节剂的药液浓度、施药频次及作用时间展开全面研究,通过测定大白刺的形态、生理生化、营养物质、根系及残留等指标,培育出矮壮、分蘖多、根系发达的植株,并筛选出改善大白刺构型的最佳施用方法,这不仅为降低施用量和提高药剂的利用效率提供理论基础,并为干旱、半干旱地区抗逆苗木的定向培育提供技术支撑。为了继续探明人工调控后不同大白刺构型的固沙机制和抗风蚀效应,基于室内风洞模拟,对施用植物生长调节剂后大白刺的防风固沙效果展开研究,为干旱区风沙危害防治和防风固沙林设计提供参考,并为人工调控大白刺理想构型标准参数的建立提供参考依据。以下为主要研究结论:(1)该植物生长调节剂不仅能够降低植株的株高、冠长、叶长、叶宽、地上鲜重及干重,而且能促进基径、冠幅、叶片数、叶厚、根长、根系平均直径、根系表面积、根系体积、根系分支强度、根尖数、根鲜重及干重。但是高施药频次(4次)会使促进作用减弱。低于0.1mm径级的根系对该植物生长调节剂的反应最强烈。交叉数的变化幅度较分叉数相对平缓。通过利用隶属函数法和TOPSIS法对不同施药频次间植物生长状况的综合评判结果中得知,当施药频次为一次或两次时,宜采用较高浓度750mg/L施药;当施药频次为3次时,宜选用600mg/L的施药浓度;当施药频次为4次时,宜施用较低浓度300mg/L施药。(2)该植物生长调节剂对植株生理生化特性具有促进作用,但高浓度会减弱其促进作用,且各试验小区均呈现先上升后下降的变化趋势(除了试验一区蒸腾速率外)。当施药频次仅为1次时,蒸腾速率的最佳施药浓度为900mg/L,但是其它生理生化指标的处理浓度都不宜超过750mg/L。7月和8月的植物光合特性指标均高于9月,且8月的光合特性指标均达到峰值。综合评判结果显示,当施药频次为1次时,宜采用较高浓度750mg/L;当施药频次为2次或3次时,宜选用600mg/L的施药浓度;当施药频次为4次时,宜采用较低浓度450mg/L。(3)除试验四区外,该植物生长调节剂对其它试验小区内的植物全氮、全磷及全钾均具有明显促进作用。不同施药频次间的养分回收效率表明,该植物生长调节剂对各养分回收效率具有促进作用,但随着施药浓度的上升,养分回收效率会出现一定的负值,且高施药频次(4次)会降低植物养分的回收效率,同时各试验小区对照组的养分回收效率均为负值。隶属函数法综合评价结果显示,对于植物养分而言,当施药频次为1次或2次时,宜选用600mg/L的浓度处理;当施药频次为3次时,宜选用较高浓度750mg/L处理;当施药频次为4次时,宜采用较低浓度450mg/L处理。(4)植物中的残留浓度(量)远高于土壤,且施药浓度与土壤和植物中的残留浓度呈正比关系,即施药浓度越高,植物生长调节剂在土壤和植物中的残留浓度越高。随着施用时间的增加,各试验小区内土壤和植物中残留浓度逐渐下降,且原始附着量与施药浓度呈正比,即施药浓度越高,植物生长调节剂的原始残留浓度(原始附着量)就越高。高施药频次和高浓度条件下植物生长调节剂被完全降解的时间会滞后。由此证明该上述施用方法(高施药频次和浓度)的可行性和安全性。(5)纺锤形大白刺对风速的减弱效果最佳,且行距越大其效果越稳定,而半球形和扫帚形的作用效果相差不多。大白刺对风速的有效减弱高度在0.2cm~14cm内,且对风速的有效减弱距离主要集中在第一排前侧0.5H至最后一排后侧-0.5H处。不同大白刺构型对风速的减弱强度随着风速的增加而增大。风速和行距对不同大白刺构型的集沙粒度参数影响较小。不同集沙仪高度下各大白刺构型的粒级百分含量主要集中在粒径为500μm~250μm范围内的中砂,其次是250μm~100μm粒径范围内的细砂,黏粒含量最少。各大白刺构型的集沙量随着风速的增加呈上升趋势。不同风速下17.5cm ×17.5cm行距内纺锤形大白刺和17.5cm × 26.25cm行距内扫帚形大白刺的阻沙效果最好。8m/s风速下扫帚形大白刺的阻沙效果优于纺锤形和半球形;而12m/s和16m/s风速下17.5cm×35cm行距内不同大白刺构型间阻沙效果差异较小。

【Abstract】 Land desertification is one of the serious global ecological environmental problems and the bottleneck of regional socio-economic development.Vegetation construction is an effective way to control desertification but the shortage of available water resources is a limiting factor for vegetation construction in desert areas.In order to improve the survival and conservation rate of vegetation in desert areas,and to solve the contradiction between vegetation growth and the shortage of available water resources,in this paper,the configuration of Nitraria roborowskii was studied after the artificial regulated by effects of plant endogenous hormones on changing the spatial morphology,increasing the plant root-crown ratio,promoting the water retention capacity from the above ground,and reducing the transpiration loss.Furthermore,the vegetation coverage in the sandy area and the ability of wind protection and sand fixation were improved.Besides,the application concentration,application frequency,and action time of the plant growth regulator by artificially regulating the ecological configuration and changing the spatial morphology of desert shrubs based on reducing water consumption were studied.The morphology,physiology and biochemistry,nutrients,roots,residues and degradation characteristics of Nitraria roborowskii were measured in order to cultivate the plants of short,strong,and root-developed and select the best application methods for improving the configuration.This not only provides a theoretical basis for reducing the amount of application and improving efficiency but also provides technical support for the targeted cultivation of resistant seedlings in arid and semi-arid areas.In order to explore the structural parameters of high-efficiency shrubs with wind-proof and sand-fixing and well understand the influence mechanism of shrubs on wind-sand movement,the effects of regulated shrubs with the different configurations on wind-resistant and sand-fixation in a wind tunnel experiment was further studied.It also provides a reference for the establishment of standard parameters for the ideal configuration of artificially regulating sandy shrubs.The results show that:The plant growth regulator not only reduced plant height,crown length,leaf length,leaf width,fresh weight and dry weight with above-ground,and it could promote the base diameter,crown width,leaf number,leaf thickness,root length,root average diameter,root surface area,root volume,root branch strength,root tip number,fresh weight and dry weight with roots.However,the high frequency(four times)would weaken the promotion effect.Besides,root diameter levels below 0.1mm responded most strongly to plant growth regulator.The variation of the crossover number was relatively flat compared to the cross number.According to the results of the comprehensive evaluation of plant growth indexes between different application frequency by a membership function and TOPSIS method,it was found that when the application frequency was one or two times,the higher concentration of 750mg/L should be used;when application frequency was three times,the concentration of 600mg/L should be selected;when application frequency was four times,the lower concentration of 300mg/L should be used.The plant growth regulator promoted the physiological and biochemical characteristics,but the high concentration weakened the promotion effect.All the experimental plots showed the changing trend of rising first and then decreasing(except for the evaporation rate in the experimental plot 1).When the application frequency was one time,the highest application concentration of the transpiration rate was 900mg/L,and the other physiological and biochemical indexes should not exceed 750mg/L.Besides,the photosynthetic characteristics in July and August were higher than those in September,and it reached the maximum in August.The comprehensive evaluation results showed that the higher concentration with 750mg/L should be used when the application frequency was one time;when the application frequency was between two and three times,600mg/L could be used;when the application frequency was four times,it is advisable to use a lower concentration with 450mg/L.In addition to the experimental plot 4,the plant growth regulator had a significant effect on total nitrogen,total phosphorus,and total potassium.The nutrient recovery efficiency of different application frequencies indicated that the plant growth regulator could promote nutrient recovery efficiency.However,the nutrient recovery efficiency would be negative with the increase of application concentration.High application frequency(four times)could reduce the nutrient recovery efficiency and the nutrient recovery efficiency of control was negative.In addition,the comprehensive evaluation results of the membership function method showed that when the application frequency was one or two times,600mg/L could be used;the higher concentration with 750mg/L should be used when the application frequency was three times;when the application frequency was four times,it is advisable to use a lower concentration with 450mg/L.The residual concentration was much higher than that in soil,and the application concentration was proportional to the residual concentration in soil and plants.The higher the application concentration was,the higher the residual concentration of plant growth regulators in soil and plants was.As the application frequency increased,the residual concentration in soil and plants gradually decreased.And the original attachment was proportional to the application concentration,which the higher the application concentration,the higher the original residual concentration(original attachment)of plant growth regulator.Moreover,the time in which residual concentration was completely degraded under the high application frequency and concentration would be delayed.The feasibility and safety of the above application method(high frequency and concentration of application)were proved.Regulated shrub with spindle-shaped had the best effect on wind speed weakening,and the greater the row space,the more stable the effect.However,the effects of regulated shrub with hemisphere-shaped and broom-shaped were almost the same.The effective weakening height of regulated shrub with different configurations was within 0.2cm-14cm.And the effective weakening distance was mainly in the front of first row 0.5H to the back of the last row-0.5H.Moreover,the decrease of wind speed in regulated shrubs with different configurations increased with the increase of wind speed.And wind speed and row space had little effect on the grain-size parameters.The grain-size percentage content under different height with sand collector was mainly concentrated in the medium sand in the range of grain-size from 500μm to 250μm,followed by fine sand in the range of 250μm to 100μm,and the clay content was the least.Furthermore,the sediment deposition of different configurations with regulated shrubs increased with the improvement of wind speed.The average sediment deposition of spindle-shaped regulated shrub in 17.5cm×17.5cm and broom-shaped regulated shrub in 17.5cm×26.25cm under wind speeds reached the highest.And there was less variation with the different configurations of regulated shrubs in 17.5cm×35cm under 12m/s and 16m/s.However,the sand resistance effect of broom-shaped regulated shrubs at 8m/s was the best.The sand resistance effect of broom-shaped regulated shrubs at 8m/s was better than that of spindle-shaped and hemisphere-shaped,while the sand resistance effect of different configurations with regulated shrubs in 17.5cm×35cm at 12m/s and 16m/s was the almost same.

Snapshot search of full-text: 

Knowledge network:

Citation network of current document
网页聊天
live chat
在线营销
live chat