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661.
662.
冷季型草坪草品种(系)的耐盐性筛选 总被引:1,自引:1,他引:0
用水培法在300 mmol.L-1 NaCl胁迫条件下对22个高羊茅、5个多年生黑麦草和26个草地早熟禾品种(系)进行了耐盐性筛选。结果表明:高羊茅品种‘Reward’、‘Micro’、‘Picasso’、‘WranglerⅡ’、‘Avenger’和品系‘T4’、‘T5’、‘T6’、‘T3’、多年生黑麦草品种‘Charismatic’和‘Eveningshade’、草地早熟禾品种‘Champlain’在生物量指标上的耐盐指数均在95%以上,表现较好;高羊茅品种‘Reward’、‘Masterpiece’、‘Avenger’和品系‘T4’、‘T6’、‘T5’、草地早熟禾品种‘Absolute’、‘Baron’和品系‘KB2’在植株绿叶数指标上的耐盐指数都在70%以上,表现较好;高羊茅品种‘TripleA’、‘Amigo’、‘Titanium’、‘Reward’和品系‘T5’、‘T6’、多年生黑麦草品种‘Impulse’在光化学效率指标上的耐盐指数都在87%以上,表现明显高于其他参试品种或品系。对3个性状为指标的耐盐指数综合聚类分析结果显示:在53个筛选的品种(系)中,均属于高羊茅的品种‘Reward’、‘TripleA’、‘Amigo’、‘Titanium’和品系‘T6’、‘T5’的耐盐性最强,可望在盐土的草坪绿化中应用。 相似文献
663.
Shuwen Zhao Luyao Qin Lifu Wang Xiaoyi Sun Lei Yu Meng Wang Shibao Chen 《Soil Use and Management》2022,38(3):1459-1469
Ecological restoration refers to the gradual recovery of damaged ecosystems by utilizing their self-recovery capacity and artificial measures. It is considered as an effective technique to alleviate heavy metal pollution in open-pit mining soils. However, little is known about the stability of heavy metals and soil bacterial responses in artificially restored soil-plant systems. In this study, different vegetation restoration strategies were established in the Dabaoshan mining area, China, and the accumulation and transfer of Cd/Pb in the soil-plant system and the responses of the soil bacterial community were investigated. Results showed that ecological restoration with a combination of trees, shrubs and grasses/herbs could increase soil cation-exchange capacity and organic matter content, but not soil pH. The mixture of trees, shrubs and grasses/herbs was most effective for reducing the available Pb content to 33.7% of the content in the control, and the mixture of trees and grasses/herbs was beneficial in reducing Cd to 60.4% of the content in the control. Data showed that ecological restoration could change the quantity, composition and community structure of soil microorganisms. The soils in which a mixture of trees, shrubs and grasses/herbs were grown had the greatest abundance and diversity of bacteria; the abundances of Proteobacteria increased by 12% and Actinobacteria by 5% from those of the control. Plant coverage, soil available Cd content, and organic matter emerged as major determinants of bacterial community composition. This study demonstrates a promising remediation strategy for limiting Cd/Pb mobility in mining areas. 相似文献
664.
长穗偃麦草是一种耐盐碱、耐旱、耐涝的多年生冷季型牧草,已在美国、加拿大、澳大利亚等国大面积种植。自1954年起,作为小麦遗传改良的重要资源,在我国长期被用作小麦远缘杂交的亲本。尽管1980-1990年代我国曾引进长穗偃麦草用于防风固沙和牧草生产,但鲜有大面积种植的报道。全世界已审定推广了10个以上的长穗偃麦草品种,而我国目前还没有自主选育的长穗偃麦草品种。2012年起中国科学院遗传与发育生物学研究所李振声组先后在北京、曹妃甸、南皮、海兴、东营等地进行多年多点种植试验,再次证实其耐盐碱高产特性。于是,2020年1月李振声提出了利用环渤海盐碱荒地种植耐盐碱牧草(如长穗偃麦草)建立“滨海草带”的设想。为此,需建立适合长穗偃麦草大面积种植的栽培技术、选育耐盐高产新品种。本研究综述了国内外有关长穗偃麦草耐盐碱、耐涝、耐旱等特点及牧草品质、品种选育、栽培技术与长穗偃麦草“滨海草带”方面的研究进展,以期为长穗偃麦草研究利用与示范推广提供参考。 相似文献
665.
Establishment of roadside plantings is often limited by adverse site conditions, particularly poor soil physical and chemical properties. We compared plant establishment of shrubs, herbaceous perennials, and grasses in response to addition of compost and/or tillage before planting in replicated plots at two locations along an interstate highway near Detroit, MI, USA. Plots at each location received one of four site preparation treatments: control (no treatment), compost only (top-dressed with 8 cm of municipal compost), tillage only (soil tilled to 20 cm) or compost + tillage (8 cm of compost added and tilled to 20 cm). Within each site preparation plot, we established sub-plots of 16 selections of shrubs, perennials, and ornamental grasses. Compost addition, plant selection, and location affected (P ≤ 0.05) plant survival, height growth, and % plant cover two years after planting. Tillage did not affect (P > 0.05) plant establishment. Similarly, the interaction of tillage × compost was not significant, indicating that surface application of compost was as effective as tilling compost into the soil. Improved plant establishment with the addition of compost was associated with improved soil and plant nutrition and reduced soil pH and soil bulk density. Within each plant group (i.e., shrubs, perennials, grasses) plant establishment varied widely. Overall, the results indicate that compost addition can improve establishment of diverse roadside plantings, which was associated with improved soil fertility. In contrast, tillage provided comparatively little benefit to plant performance in this trial. 相似文献
666.
频繁的灌溉,使人工草地的高羊茅生长在盐渍化或潜在盐渍化环境中。硅可以抑制植物对Na+的吸收,增加对N、P和K+的吸收,从而提高植物的耐盐性,且这种影响因植物种类和品种的不同而不同。本研究采用盆栽试验,研究了不同程度盐生境下施硅对两个高羊茅品种(抗性弱的K31和抗性强的XD)生物量和植株N、P、K+、Na+含量的影响。结果表明,随着盐浓度的增加,两个高羊茅品种地上和地下生物量、N、P、K+含量降低,Na+含量增加。施硅对地上和地下生物量、N、P、K+、Na+含量的影响与盐浓度有关,在中低盐浓度下,施硅增加了高羊茅的地上、地下生物量、根冠比、N、P、K+ 含量、K+/ Na+ 值,降低了Na+含量。高盐浓度时,施硅对高羊茅的生物量和N、P、K+、Na+含量没有影响。施硅对两个高羊茅品种地上和地下生物量、Na+、P含量的影响相似,对K+、N含量的影响不同,硅对耐盐性较强的XD地上部K+及N含量的有利影响优于耐盐性较弱的K31。结果表明,在低中盐浓度条件下,施硅可以促进高羊茅的生长,并且对耐盐性较强的高羊茅品种XD更为有利。 相似文献
667.
为研究探讨苇状羊茅原料的青贮特性,青贮饲料发酵品质、营养物质含量,以结实期的新鲜或晾晒苇状羊茅为原料,分别设计对照、添加甲酸(6 mL/kg)或蔗糖(2%)处理,袋装密封青贮360 d后取样分析其发酵品质与养分含量。结果表明,晾晒可以显著降低苇状羊茅青贮饲料的pH和乳酸含量(P0.05),极显著降低氨态氮含量(P0.01)。添加甲酸和蔗糖都能够显著降低苇状羊茅青贮饲料的pH(P0.05),极显著降低乙酸和氨态氮含量(P0.01),极显著提高乳酸含量(P0.01)。晾晒或添加剂处理对苇状羊茅青贮饲料常规养分的影响不明显,青贮之后硝酸盐含量显著降低。苇状羊茅在单独青贮时具有调制为优质青贮饲料的特征。 相似文献
668.
Lui Yuxin Nanjing Architetural Civil Engineering InstituteFeng Yiran Chongqing Institute of Architecture Engineering 《保鲜与加工》1988,(1)
This paper investigates the dynamic response of tall buildings subject toalongwind loading.According to the assumptions of the fundamental parame-ters,the function of the first vibration mode and that of the mass model,thecomputer program AWCTS is compiled.The availability of the procedure in thispaper is verified through practical calculations and comparison of results. 相似文献
669.
在大气边界层风洞中模拟了C,D两类地貌的风场,对某市区办公楼进行了风洞试验,分析了不同风场下高层建筑风压分布特性、风荷载及风致响应特性.结果表明:C类风场下平均风压系数、总体弯矩系数、最大基底剪力和最大基底弯矩均大于D类风场的对应值;C类风场下办公楼风荷载大于D类风场下办公楼风荷载;C类风场下各测点风压谱峰值对应频率均小于D类风场下各测点风压谱峰值对应频率;C类风场下结构顶部峰值加速度大于D类风场下结构顶部峰值加速度. 相似文献
670.