共查询到19条相似文献，搜索用时 171 毫秒
1.
在2008、2009年向日葵需肥规律、播期、密度、抗旱性比较等单项试验的基础上,2010年在内蒙古农业大学科技园区对以上试验结论进行技术组装集成,并与传统农户种植模式进行比较试验,以进一步明确不同栽培模式下向日葵根系发育特性,并对根系特征差异进行分析.研究结果表明:不同种植模式产量存在显著差异,油葵、食葵集成模式下分别增产18.58％、23.28％;集成模式的根系干物质积累最大速率出现时间提前,速率增大,持续时间长,0～ 20 em土层根系分布90％左右,根系趋于下扎;集成模式的群体根体积、根长、根活跃吸收面积等均大于农户模式,且全生育期最大值大于农户模式. 相似文献
2.
新疆短合植物根系特征与立地条件的关系 总被引：11，自引：0，他引：11
对早春短命植物根系和立地条件的研究表明：早春短命植物的根系大都分布在土壤浅层;４月份是其根系发育的主要阶段。生境条件对短命植物根系的分布有明显影响;同种植物的根系类型会随生境条件的改变而变化。土壤类型和土壤水分条件是环境因子中影响根系发育及根系类型分布的主要因素。 相似文献
3.
新疆短命植物根系特征与立地条件的关系 总被引：6，自引：1，他引：5
对早春短命植物根系和立地条件的研究表明:早春短命植物的根系大都分布在土壤浅层;4月份是其根系发育的主要阶段.生境条件对短命植物根系的分布有明显影响;同种植物的根系类型会随生境条件的改变而变化.土壤类型和土壤水分条件是环境因子中影响根系发育及根系类型分布的主要因素. 相似文献
4.
玉米大豆条带间作根系分布模式 总被引：3，自引：0，他引：3
在土壤剖面上冲洗根系,观测玉米/大豆条带间作模式下根系的生长分布及动态变化规律;使用二次曲线和修正的Logistic函数拟合根系下扎深度和侧向伸展距离与播后天数(DAS)的关系;引入根系的相对侧向伸展距离(RLD)与相对深度(RD)两个概念,将根系下扎深度和侧向伸展距离归一化,利用高斯函数拟合RLD与RD的关系,建立根系分布函数.结果表明,该根系分布函数对玉米大豆间作模式下的根系生长分布状况有很好的模拟性. 相似文献
5.
极端干旱区胡杨根系分布对土壤水分的响应 总被引：3，自引：1，他引：2
依据2006和2007年6月至7月在极端干旱区额济纳的实测资料,利用分形和统计的方法对胡杨根系分布与根区土壤水分的关系进行了分析研究,建立了土壤含水率与根系分维值之间的函数关系。根系土壤水分的变化对胡杨根系分布有直接影响,当平均土壤含水率小于0.11 cm3/cm3时,根系分布的分形维数随土壤含水率的增加而增大;当土壤含水率期望值大于0.11 cm3/cm3时,根系分布的分形维数随土壤含水率的增加而减小。平均土壤含水率在0.06-0.3 cm3/cm3之间,是适宜胡杨根系生长的范围。 相似文献
6.
谷子根系生长发育规律及环境条件对其影响的研究 总被引：5，自引：0，他引：5
以大田挖根和挖坑用水冲根的方法研究了谷子根系生长发育规律，并以磷肥试验、地膜覆盖栽培，分期播种栽培等方法研究了环境条件对谷子根系生长发育的影响。结果表明：一株成熟的谷子有须根４０－８０条，６－８轮；谷子根系入土深达１５５ｃｍ，扩直径为９０ｃｍ，主要分布在６０ｃｍ土层中，占总根量的９７．５１％；根系发生，拔节前较慢，拔节抽穗发生快，抽穗后又慢，灌浆时停止发生。 相似文献
7.
毛乌素沙地沙柳与柠条根系分布特征对比 总被引：9，自引：2，他引：7
采用土柱法对毛乌素沙地沙柳与柠条的根系进行了研究。研究表明:沙柳与柠条均为主根型植物,沙柳的水平根更为发达。三年生沙柳根系水平分布在距树基160cm范围内的土层中,距树基0～40cm范围内根系分布最多,占总根量的78.73%;柠条根系水平分布在距树基60cm范围内的土层中,占总根量的78.58%。沙柳根系垂直分布在60cm土层以上,而柠条根系垂直分布在30cm至90cm土层之间。 相似文献
8.
局部灌水方式对冬小麦产量与水分利用的影响 总被引：2，自引：0，他引：2
以根系对土壤水分的吸收利用规律、土壤养分在土层中的分布规律和农田土壤蒸发特征为基础,研究局部不同节水高产灌水方式,是解决水肥异位问题和实现“浇作物”的新尝试。2000～2002年连续两年的试验结果表明,测坑内灌溉5水的处理与筒栽灌溉7水的处理有最高的产量和千粒重,适宜的灌水量是30mm。提高作物产量和水分利用效率的灌溉方式应该是灌水集中在作物主要根系分布层,实施高频局部灌溉。 相似文献
9.
浑善达克沙地榆树根系分布特征及生物量研究 总被引：20，自引：5，他引：20
本文采用挖掘法对浑善达克沙地榆树的根系进行了研究。研究表明 ,草被层的根系主要分布在土壤表层 ,榆树根系则占据了 2 0 cm以下的土层空间。根系的垂直分布在冠缘内主要集中在 2 m深范围内 ,冠缘外则集中分布在 1 m深的土层中 ,不同的根系剖面形成不同的根栖层 ;根系的水平分布呈近密远疏的趋势 ,其半径为 1 1 m左右。根量的垂直分布随土层深度增加呈先增加后降低的趋势 ;其水平分布随着距根基距离的增大而减少 ,以 3m内最为密集 ,冠缘内根量为冠缘外根量的 1 2倍。 相似文献
10.
《干旱区研究》2021,38(5):1420-1428
根系是植物吸收水分和养分的主要器官,发育及分布情况对植物生长具有极其重要的影响。本研究以甘肃省定西市安定区龙滩流域的人工白杨林、油松林以及山杏林为研究对象,分析了3种人工林总根及不同径级的根长、根面积、根生物量密度的垂直分布特征及其与土壤理化性质之间的关系,旨在从根系分布角度比较黄土丘陵区典型人工林之间的生长差异,为该区域植被恢复与评价提供一定的科学依据。研究结果表明:(1)不同径级的根系分布中3种人工林均以细根为主,细根与总根的根长及根面积密度均表现为白杨林油松林山杏林,根生物量密度表现为油松林白杨林山杏林,而中根与粗根的根长及根面积密度均以油松林为最高。(2)垂直土壤剖面上,3种人工林总根与细根的根长、根面积及根生物量密度整体上呈现出随土壤深度的增加而减少的趋势,而中根与粗根的垂直分布规律并不明显。(3)细根和总根的根长密度、根面积密度、根生物量密度与土壤全碳、全氮、有机碳及含水量均呈极显著正相关关系,中根的根长及根面积密度与土壤全碳、全氮、全磷及有机碳含量呈显著相关关系,粗根的根长及根面积密度与土壤全碳呈显著相关关系,土壤碳氮含量以及含水量的增加与林木根系的生长在一定程度上存在协同效应。 相似文献
11.
《干旱区科学》2016,(6)
Saline wetlands are rare ecosystems in Saharan areas,which are important for conservation of many endemic and rare plant species.In this study,we investigated five saline wetland sites of the Oued Righ region,located in the northeastern Algeria,to determine the environmental factors controlling the composition and distribution of plant communities.We established a total of 20 transects to measure the vegetation parameters(density and cover) and soil characteristics(electrical conductivity,moisture,pH,CaSO_4,CaCO_3,organic matter,Na~+,K~+,Mg~(2+),Ca~(2+),SO_4~(2–),Cl~–,NO_3~– and HCO_3~–).A total of 17 plant species belonging to seven families were identified.The natural vegetation was composed of halophytic and hydro-halophytic plant communities,presented specially by the species of Amaranthaceae family.Soils in the studied wetlands were moist,gypsiferous,alkaline,salty to very salty with dominance of chloride and calcium.Results of the Canonical Correspondence Analysis(CCA) showed that community structure and species distribution patterns of vegetation were mainly dependent on soil characteristics,mainly being soil salinity(CaSO_4,K~+,Ca~(2+) and Cl~–) and moisture.The distribution of plant species was found to follow a specific zonal pattern.Halocnemum strobilaceum was observed to grow in highly salt-affected soils,thus being the more salt-tolerant species.Phragmites communis plants were widely distributed in the study area with a high density at the edges of accumulated water body.Juncus maritimus,Tamarix gallica and Salicornia fructicosa grew in soils that are partially or completely flooded in winter.Suaeda fructicosa,Traganum nudatum,Arthrocnemum glaucum,Aeluropus littoralis,Cressa cretica and Cynodon dactylon were distributed in salty and moist soils away from the open water body.Plants of Zygophyllum album,Limonastrirum guyonianum,Cornulaca monacantha,Cistanche tinctoria,Mollugo nudicaulis and Sonchus maritimus were found in soils with less salty and moisture.They constituted the outermost belt of vegetation in the studied wetlands.This study will provide a reference on introducing the salt-tolerant plant species as a fodder resource in saline habitats and regenerating the degraded saline wetlands. 相似文献
12.
Vertical distribution of root damage caused by Rhizoctonia solani within a rhizoctonia patch was examined on five occasions during the growing season using a soil core technique. The effect of depth on root damage was assessed by determining root growth of wheat seedlings grown in cores of undisturbed soil taken at depths 0−2−5, 2−5−5−0, 5−0−7−5 and 7−5−10 cm from both inside and outside a patch. Within the patch most of the damage occurred in the top 5 0 cm of soil with less in the next 2−5 cm and least in the 7−5−10 cm zone. Outside the patch, soil depth had little or no effect on root growth. 相似文献
13.
FanJiang ZENG Cong SONG HaiFeng GUO Bo LIU WeiCheng LUO DongWei GUI Stefan ARNDT DaLi GUO 《干旱区科学》2013,(2):220-232
Alhagi sparsifolia Shap. (Fabaceae) is a spiny, perennial herb. The species grows in the salinized, arid regions in North China. This study investigated the response characteristics of the root growth and the distribution of one-year-old A. sparsifolia seedlings to different groundwater depths in controlled plots. The ecological adaptability of the root systems of A. sparsifolia seedlings was examined using the artificial digging method. Results showed that: (1) A. sparsifolia seedlings adapted to an increase in groundwater depth mainly through increasing the penetration depth and growth rate of vertical roots. The vertical roots grew rapidly when soil moisture content reached 3%-9%, but slowly when soil moisture content was 13%-20%. The vertical roots stopped growing when soil moisture content reached 30% (the critical soil moisture point). (2) The morphological plasticity of roots is an important strategy used by A. sparsifolia seedlings to obtain water and adapt to dry soil conditions. When the groundwater table was shallow, horizontal roots quickly expanded and tillering increased in order to compete for light resources, whereas when the groundwater table was deeper, vertical roots developed quickly to exploit space in the deeper soil layers. (3) The decrease in groundwater depth was probably responsible for the root distribution in the shallow soil layers. Root biomass and surface area both decreased with soil depth. One strategy of A. sparsifolia seedlings in dealing with the increase in groundwater depth is to increase root biomass in the deep soil layers. The relationship between the root growth/distribution of A. sparsifolia and the depth of groundwater table can be used as guidance for harvesting A. sparsifolia biomass and managing water resources for forage grasses. It is also of ecological significance as it reveals how desert plants adapt to arid environments. 相似文献
14.
不同生育阶段咸水滴灌对红枣根区土壤有机碳垂直分布特性的影响 总被引：2，自引：0，他引：2
为探索咸水滴灌对红枣根区土壤有机碳含量的影响,采用大田咸水滴灌试验,在不同的灌水定额和咸水矿化度条件下,对红枣不同生育阶段根区土壤有机碳的影响进行分析。结果表明：不同矿化度的咸水滴灌处理后,不同生育阶段红枣根区土壤有机碳,随着土层深度的增加呈“S”形变化,影响土壤有机碳的咸水矿化度依次为：3 g/L＞4 g/L＞淡水对照＞2 g/L,表层10～30 cm的土壤有机碳含量较30～50 cm处高,而30～40 cm土层的有机碳含量相对最小。当矿化度一定时,影响红枣根区土壤有机碳含量的灌水定额依次为：30 L＞20 L＞10 L,说明在利用咸水灌溉时,适度增加灌水量是弱化盐分对土壤有机碳产生影响的有效途径。相对于其他处理,灌水定额为30 L,矿化度为2 g/L的咸水滴灌在促进枣树根系对土壤有机碳利用方面的影响最显著。 相似文献
15.
Saline wetlands are rare ecosystems in Saharan areas, which are important for conservation of many endemic and rare plant species. In this study, we investigated five saline wetland sites of the Oued Righ region, located in the northeastern Algeria, to determine the environmental factors controlling the composition and distribution of plant communities. We established a total of 20 transects to measure the vegetation parameters (density and cover) and soil characteristics (electrical conductivity, moisture, pH, CaSO4, CaCO3, organic matter, Na+, K+, Mg2+, Ca2+, SO42–, Cl–, NO3– and HCO3–). A total of 17 plant species belonging to seven families were identified. The natural vegetation was composed of halophytic and hydro-halophytic plant communities, presented specially by the species of Amaranthaceae family. Soils in the studied wetlands were moist, gypsiferous, alkaline, salty to very salty with dominance of chloride and calcium. Results of the Canonical Correspondence Analysis (CCA) showed that community structure and species distribution patterns of vegetation were mainly dependent on soil characteristics, mainly being soil salinity (CaSO4, K+, Ca2+ and Cl–) and moisture. The distribution of plant species was found to follow a specific zonal pattern. Halocnemum strobilaceum was observed to grow in highly salt-affected soils, thus being the more salt-tolerant species. Phragmites communis plants were widely distributed in the study area with a high density at the edges of accumulated water body. Juncus maritimus, Tamarix gallica and Salicornia fructicosa grew in soils that are partially or completely flooded in winter. Suaeda fructicosa, Traganum nudatum, Arthrocnemum glaucum, Aeluropus littoralis, Cressa cretica and Cynodon dactylon were distributed in salty and moist soils away from the open water body. Plants of Zygophyllum album, Limonastrirum guyonianum, Cornulaca monacantha, Cistanche tinctoria, Mollugo nudicaulis and Sonchus maritimus were found in soils with less salty and moisture. They constituted the outermost belt of vegetation in the studied wetlands. This study will provide a reference on introducing the salt-tolerant plant species as a fodder resource in saline habitats and regenerating the degraded saline wetlands. 相似文献
16.
科尔沁差巴嘎蒿根系分布规律与土壤水分关系的研究 总被引：3，自引：0，他引：3
以生长在科尔沁大青沟两侧台面上的差巴嘎蒿为研究对象,采用整株挖掘的方法,研究差巴嘎蒿根系分布的规律。结果表明:差巴嘎蒿根系垂直分布深度为0～90㎝,其中0～30㎝的土层中根系分布最多,占根系总长度的85.74%,水平方向上表现为近密远疏的趋势;整体上根系呈主根型分布,形态上呈"伞"型分布。差巴嘎蒿根系分布与土壤水分密切相关。随着深度的增加,土壤含水量逐渐增大,但根系长度、生物量及密度均逐渐降低,两者呈负相关关系,其中根长平均变化率-12.61%、根生物量平均变化率-29.07%,均大于土壤含水量平均变化率7.92%,但比根长却与土壤含水量呈正相关关系,且比根长平均变化率7.58%与土壤含水量平均变化率7.92%相差不大。 相似文献
17.
CHEN Pengpeng 《干旱区科学》2021,13(9):947-961
Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid regions. Drought is the main factor limiting the local agricultural production in the Loess Plateau of China. In this study, we tried to select a suitable ridge-furrow mulching system to improve this situation. A two-year field experiment of summer maize (Zea mays L.) during the growing seasons of 2017 and 2018 was conducted to systematically analyze the effects of flat planting with no film mulching (CK), ridge-furrow with ridges mulching and furrows bare (RFM), and double ridges and furrows full mulching (DRFFM) on soil temperature, soil water storage (SWS), root growth, aboveground dry matter, water use efficiency (WUE), and grain yield. Both RFM and DRFFM significantly increased soil temperature in ridges, while soil temperature in furrows for RFM and DRFFM was similar to that for CK. The largest SWS was observed in DRFFM, followed by RFM and CK, with significant differences among them. SWS was lower in ridges than in furrows for RFM. DRFFM treatment kept soil water in ridges, resulting in higher SWS in ridges than in furrows after a period of no water input. Across the two growing seasons, compared with CK, RFM increased root mass by 10.2% and 19.3% at the jointing and filling stages, respectively, and DRFFM increased root mass by 7.9% at the jointing stage but decreased root mass by 6.0% at the filling stage. Over the two growing seasons, root length at the jointing and filling stages was respectively increased by 75.4% and 58.7% in DRFFM, and 20.6% and 30.2% in RFM. Relative to the jointing stage, the increased proportions of root mass and length at the filling stage were respectively 42.8% and 94.9% in DRFFM, 63.2% and 115.1% in CK, and 76.7% and 132.1% in RFM, over the two growing seasons, showing that DRFFM slowed down root growth while RFM promoted root growth at the later growth stages. DRFFM treatment increased root mass and root length in ridges and decreased them in 0-30 cm soil layer, while RFM increased them in 0-30 cm soil layer. Compared with CK, DRFFM decreased aboveground dry matter while RFM increased it. Evapotranspiration was reduced by 9.8% and 7.1% in DRFFM and RFM, respectively, across the two growing seasons. Grain yield was decreased by 14.3% in DRFFM and increased by 13.6% in RFM compared with CK over the two growing seasons. WUE in CK was non-significantly 6.8% higher than that in DRFFM and significantly 22.5% lower than that in RFM across the two growing seasons. Thus, RFM planting pattern is recommended as a viable water-saving option for summer maize in the Loess Plateau of China. 相似文献
18.
ABSTRACT The vertical distribution of Pratylenchus penetrans was monitored in four fields cropped with maize, black salsify, carrot, or potato. Soil samples were collected at 21-day intervals from May 2002 until April 2003 from five plots (2 x 5 m(2)) per field. Per plot, 15 cores were taken to a depth of 70 cm and split into seven segments of 10 cm each. Within the plots, segments from corresponding depths were pooled. After mixing, 200-g subsamples were taken and nematodes were extracted by zonal centrifugation from the root fraction and the mineral soil fraction separately. In most crops, the root fraction contained more than 50% of the total number of P. penetrans. Because the ratio between the numbers of nematodes in the root fraction and mineral soil fraction changes during the growing season, numbers of P. penetrans found in the mineral soil fraction cannot be used to estimate the total number in the soil. Therefore, both fractions have to be processed to obtain a reliable estimate of the density. No nematodes were recovered below 50 cm soil depth, except in the maize field where nematodes were found at 70 cm. The optimum sampling depth for maize, black salsify, carrot, and potato was 45, 25, 25, and 35 cm, respectively. The percentage of nematodes per soil layer was independent of the sampling date, indicating that a defined optimum sampling depth will be applicable throughout all seasons. The cumulative vertical distribution, modeled with a logistic equation, can be used to estimate the sampling error when samples are collected at different depths. 相似文献
19.
节水抗旱与喜水肥型小麦品种土壤水分消耗特性的比较研究 总被引：2，自引：0，他引：2
分别以节水抗旱型小麦品种邯5316和喜水肥型品种邯3475为供试材料,进行了不同品种类型冬小麦土壤水分消耗特性及根系生长规律的比较研究。结果表明:节水抗旱型小麦根系发达,灌浆后期,在只浇春季1水的情况下,抗旱型品种50～200cm土壤层根长密度占0～200cm总根长密度的56.3%,单株总根重0.33g,其中50～200cm根重占总根重的22%,而喜高水肥型品种在春季只浇1水的情形下各值分别为52.1%,0.25g,19.4%。根系发育与分布的结果是抗旱型小麦品种对土壤水分的利用率更高,是相同灌水处理喜高水肥品种的115%,是本品种春季灌3水处理的190%,其对土壤水分利用效率高可体现在0～200cm土体的各个层次上,特别是对100cm以下土壤层的水分利用率也较高。但结果同时表明,抗旱型小麦对土壤水分的充分利用在小麦、玉米两熟种植制度下,对夏玉米前期生长有一定的影响,应该注意对夏玉米前期的水分管理。 相似文献