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1.
毛乌素沙地沙柳、乌柳及旱柳蒸腾耗水变化规律的研究   总被引:3,自引:0,他引:3  
蒸腾是植物耗水特征的主要方式,在土壤-植物-大气连续体(SPAC)水热传输过程中占有极为重要的地位,一直是农学、林学、气象学、水文学、生态学等相关学科及领域共同关注的重要课题之一[1].随着水资源紧缺问题的日益严重化,蒸腾问题的研究业已受国际社会的愈加重视.揭示林木耗水规律及其影响机制对水资源紧缺地区林业建设战略规划、林种布局、树种选择、林分结构配置及林地水分管理等具有重要的理论指导意义[2].  相似文献   

2.
富营养化水中14种野生植物蒸腾和营养吸收的相关性   总被引:5,自引:0,他引:5  
研究了富营养化水栽培下14种野生植物蒸腾和营养吸收的关系,结果表明,植物的日蒸腾量大小顺序与植物对环境因子的响应一致,且高蒸腾量的6种植物对环境因子的响应显著大于其它低蒸腾量的植物(P<0.05);植物的日蒸腾量与营养元素的吸收也存在着显著正相关,因此,日蒸腾量可作为人工湿地净化工程植物选种的一个重要指标。本项结果表明,鸭芹、凤眼莲、芦苇、早熟禾、水芹共5种植物可选为人工湿地净化工程的植物。  相似文献   

3.
华北石质山区山茱萸人工林蒸腾特征及水分供求关系   总被引:8,自引:1,他引:8  
于2005年及2006年主要生长季节(4-9月),采用由热扩散植物液流技术测算得到的蒸腾速率数据,结合同步观测得到降雨量,分析华北石质山区15年生山茱萸人工林耗水规律及水分供求关系.结果表明:1)山茱萸人工林蒸腾量呈现出明显的日际变化或月变化特征.表现为4-5月逐渐升高、6月左右达到高峰值、7月以后逐渐降低.2005年及2006年4-9月蒸腾总量分别为265.3和194.9 mm,4-9月各月蒸腾总量占蒸腾总量的比例在2005年分别为10.7%、22.3%、21.6%、21.2%、12.9%和11.2%,在2006年分别为16.2%、20.2%、20.3%、17.9%、13.6%和11.2%;2)蒸腾与冠层太阳总辐射、空气温度、湿度及风速等微气象要素有很好的复相关性(α=0.01),偏相关系数表明,各月内影响蒸腾的最主要微气象因子都是冠层太阳总辐射;3)4-9月降雨总量与蒸腾总量的比值(R/Tr)>1.0,且除4月外,其他各月R/Tr也大于或接近于1.0,说明除4月外,降水可以满足山茱萸人工林蒸腾耗水的需要.  相似文献   

4.
TCP植物蒸腾抑制剂是山西省林业科学研究院研制的成果,该制剂通过缩小植物气孔开张度而抑制蒸腾,减少植物水分散失。同时增加叶绿素含量,促进根系生长,提高抗旱抗寒能力,减少树木运输及移植时失水,促使盆栽植物矮壮,提高块茎、球茎作物产量。选择日最低气温不低于-5℃的无风、晴朗的早晨或傍晚。  相似文献   

5.
科技信息     
TCP植物蒸腾抑制剂TCP植物蒸腾抑制剂是山西省林业科学研究院研制的成果,该制剂通过缩小植物气孔开张度来抑制蒸腾,减少植物水分散失。同时增加叶绿素含量,促进根系生长,提高抗旱抗寒能力,提高造林绿化成活率。选择无风、晴朗的早晨或傍晚,将本药剂稀释后均匀喷施于叶面、枝干(  相似文献   

6.
山西太岳山辽东栎夏季树干液流通量研究   总被引:21,自引:2,他引:21  
树干液流指蒸腾在植物体内引起的上升液流。土壤液态水进入根系后 ,由茎输导组织向上运送达冠层 ,经由气孔蒸腾 (包括角质层及皮孔蒸腾 )转化为气态水扩散到大气中去。根部吸收的水分有 99 8%以上消耗在蒸腾上 (王沙生等 ,1 991 )。通过精确测算茎流量 ,可以基本确定植株蒸腾失  相似文献   

7.
TCP植物蒸腾抑制剂是山西省林业科学研究院研制的成果。该制剂是以通过缩小植物气孔开张度来抑制蒸腾,减少水分散失,同时增加植物叶绿素含量来提高植物抗旱能力,提高造林绿化成活率,是一种广泛用于林业、农业,投资小、见效高的创新产品。1TCP植物蒸腾抑制剂适用范围水剂500ml/瓶,使用时稀释至所需浓度即可。粉剂每袋53.80g,使用时先用少量温水溶解,然后释至所需浓度。该剂适用于针叶树、阔叶树、荒山绿化苗、盆栽植物、果树等,有效期2年。2TCP植物蒸腾抑制剂的作用机理TCP植物蒸腾抑制剂主要是通过缩小植物气孔开张度抑制蒸腾,减少植物…  相似文献   

8.
《福建林业科技》2015,(4):37-41
在对漳州市绿化树种调查的基础上,选择13种常见的园林绿化植物,利用CIRAS-2便携式光合作用测定系统对植物光合及蒸腾等生态指标进行测定及量化分析。结果表明:13种植物的瞬时光合速率曲线多为单峰曲线,峰值多出现在10∶00—12∶00之间;而供试植物日间的瞬时蒸腾速率多呈现单峰曲线,峰值多出现在14∶00左右。金心榕、垂榕、樱花、红花檵木、三角梅、黄蝉、海桐的日间固碳释氧及蒸腾吸热能力较强,而杨桃、红背桂的日间固碳释氧及蒸腾吸热能力较弱。  相似文献   

9.
《山西林业科技》2014,(4):32-32
<正>TCP植物蒸腾抑制剂是山西省林业科学研究院研制的成果,该制剂通过缩小植物气孔开张度来抑制蒸腾,减少植物水分散失。同时增加叶绿素含量,促进根系生长,提高抗旱抗寒能力,提高造林绿化成活率。选择无风、晴朗的早晨或傍晚,将本药剂稀释后均匀喷施于叶面、枝干(滴水为度),连续喷施3次,间隔期为10 d~15 d.TCP植物蒸腾抑制剂研制成功以来,在山西省荒山绿化、通道绿化工程中进行了推广,针叶树造林成活率提  相似文献   

10.
正TCP植物蒸腾抑制剂是山西省林业科学研究院的研究成果,该制剂通过缩小植物气孔开张度来抑制蒸腾,减少植物水分散失。同时增加叶绿素含量,促进根系生长,提高抗旱抗寒能力,提高造林绿化成活率。选择无风、晴朗的早晨或傍晚,将本药剂稀释后均匀喷施于叶面、枝干(滴水为度),连续喷施3次,间隔期为10 d~15 d.TCP植物蒸腾抑制剂研制成功以来,在山西省荒山造林、通道绿化工程中进行了推广,针叶树造林成活率提  相似文献   

11.
雷州半岛尾叶桉人工林树液茎流特征的研究   总被引:20,自引:1,他引:20       下载免费PDF全文
应用热脉冲法对雷州半岛4年生尾叶桉单株树干液流时空的动态变化及与各环境因子的关系进行观测研究.研究结果表明(1)形成层以内木质部不同深度的茎流密度不同,其中靠近形成层部分液流速度较快,但各层都具有相同的日变化趋势,中午12点至1点达到最大;夜间因根压作用影响各层仍有微弱上升液流;各深度日平均茎流密度11.6 L·m-2·d-1,最大为15.3 L·m-2·d-1(晴天),最小仅为5.4 L·m-2·d-1(雨天);(2) 不同直径尾叶桉的日茎流密度具有相似日变化趋势,胸径与高度相近其茎流密度相同,大树较小树快,这主要与树木根系吸收土壤水分的能力有关;(3)热脉冲法与整树容器法对2年生幼树耗水量的同步测定结果相一致,误差仅为3.4%;(4)树干茎流量与饱和蒸气压差和太阳辐射相关性特别显著.  相似文献   

12.
[目的]以大兴安岭北部典型寒温带针叶林优势建群树种兴安落叶松为对象,分析不同分化等级林木树干液流对环境因子的综合响应,构建不同分化等级林木树干液流模型。[方法]利用热扩散式液流监测系统和通量塔的梯度气象系统连续监测树干液流及环境因子的变化。[结果]表明:1)观测期间,优势木具有较强的蒸腾能力,其平均液流密度分别为中等木和被压木的1.9倍、2.5倍。总体上,分化程度越高的林木日树干液流持续时间越长,液流密度峰值出现时间越早,液流密度的峰值也越高。2)利用主成分分析将降雨、净辐射、空气温度、空气湿度、风速、土壤温度、土壤含水量和水汽压亏缺降维为蒸发需求因子(EDI)、土壤水热因子和降水因子。EDI(与净辐射、温湿度、水汽压亏缺显著相关)是影响该地区林木树干液流的关键环境要素,其携带环境数据信息量的45%;土壤水热因子和降水因子分别携带20%和13%。3)各分化等级林木树干液流密度对EDI呈顺时针时滞,对净辐射和水汽压亏缺则分别呈逆时针、顺时针时滞,且EDI的时滞效应明显较小。不同分化等级林木液流密度对EDI和水汽压亏缺的时滞表现一致,对净辐射的时滞则以优势木最小。4)各分化等级林木树干液流密度对EDI的响应均符合"S"型模型,即液流升高到阈值后,不再随蒸发需求的增加而增大。模型中,中等木(0.458)和被压木(0.457)的过渡斜率略高于优势木(0.443),表明优势木树干液流对环境因子的敏感性略低。该模型对不同分化等级林木液流密度的模拟精度均在90%以上,考虑EDI的时滞效应或引入土壤水热因子、降水因子对模型精度的影响较小。[结论]兴安落叶松树干液流对综合环境因子存在较强的响应性,且在不同分化等级间存在差异;利用"S"模型和综合环境因子可有效估算不同分化等级兴安落叶松的树干液流。  相似文献   

13.
Recently, canopy transpiration (Ec) has been often estimated by xylem sap-flow measurements. However, there is a significant time lag between sap flow measured at the base of the stem and canopy transpiration due to the capacitive exchange between the transpiration stream and stem water storage. Significant errors will be introduced in canopy conductance (gc) and canopy transpiration estimation if the time lag is neglected. In this study, a cross-correlation analysis was used to quantify the time lag, and the sap flow-based transpiration was measured to parameterize Jarvis-type models of gc and thus to simulate Ec of Populus cathayana using the Penman–Monteith equation. The results indicate that solar radiation (Rs) and vapor pressure deficit (VPD) are not fully coincident with sap flow and have an obvious lag effect; the sap flow lags behind Rs and precedes VPD, and there is a 1-h time shift between Ec and sap flow in the 30-min interval data set. A parameterized Jarvis-type gc model is suitable to predict P. cathayana transpiration and explains more than 80% of the variation observed in gc, and the relative error was less than 25%, which shows a preferable simulation effect. The root mean square error (RMSEs) between the predicted and measured Ec were 1.91 × 10?3 (with the time lag) and 3.12 × 10?3 cm h?1 (without the time lag). More importantly, Ec simulation precision that incorporates time lag is improved by 6% compared to the results without the time lag, with the mean relative error (MRE) of only 8.32% and the mean absolute error (MAE) of 1.48 × 10?3 cm h?1.  相似文献   

14.
尤龙辉 《防护林科技》2013,(12):48-50,64
利用TDP径流计对福建沿海木麻黄南北方位的边材液流动态进行长期监测,并同步检测空气温湿度、太阳辐射等环境因子,分析南北方位液流速率的相互关系、对蒸腾耗水量测算的影响以及与环境因子的关系。结果显示,木麻黄南北2个方位测得的液流速率存在显著差异和线性相关。木麻黄生长季(5~10月)内单株蒸腾耗水量与日总太阳辐射和昼间平均空气水汽压亏缺的指数饱和曲线拟合效果较好。采用单方位树干液流速率测算的整株蒸腾耗水量与2个方位的测算值相差18.19%。  相似文献   

15.
本研究采用由热扩散植物液流技术测算得到的时间步长10 min的樟子松蒸腾速率数据,结合同步观测得到的冠层微气象要素值,分析了毛乌素沙区20年生樟子松主要生长季节蒸腾耗水规律及其冠层微气象的关系.结果表明:(1)樟子松蒸腾速率具有明显的时间变化特征.多云天气日,蒸腾速率日内变化总体呈多峰曲线趋势,单株蒸腾速率(Tr)在4-9月各月白天(6:00-19:00)的平均值为0.36~0.85 L·h-1;晴天日,除9月蒸腾速率日内变化呈多峰曲线趋势外,其余各月总体趋势呈单峰曲线,9月时Tr在10:00左右、13:00左右、15:00左右出现峰值,在14:00左右出现谷值.4-8月各月日内Tr在10:00左右出现峰值.4-9月各月Tr白天平均值为0.37~0.83 L·h-1;阴天天气日,蒸腾速率日内变化总体呈单峰曲线趋势,日内Tr最大值出现在10:00左右.4-9月各月Tr白天(6:00-19:00)平均值为0.29~0.63 L·h-1.在日际变化或季节变化方面,从4月份起,樟子松蒸腾耗水量逐渐增加,月耗水量在7月达到最高值,此后有所减小.4-9月总耗水量为1 143.7 mm,日平均为6.25 mm,7月份月耗水总量相对最大.4、5、6、7、8及9月耗水量分别占主要生长季节总量的10.76%、13.62%、14.05%、24.56%、19.47%、17.52%.(2)主要生长期内,Tr与冠层太阳总辐射(Ra),空气温度(Ta)、湿度(RH),风速(V)等气象要素有很好的复相关性,并通过显著性检验(a=0.01),且各月内影响樟子松蒸腾的最主要气象因子都是Ra.  相似文献   

16.
银杏树干茎流变化及其对抑制蒸腾措施的响应   总被引:13,自引:2,他引:13  
利用GREENSPAN茎流测定系统监测银杏树干茎流动态变化.结果表明:树干不同高度、不同深度和不同方位的茎流速率存在差异.上位的茎流速率高于中位和下位,但通过上中下位截面的累积茎流通量差异不显著;在不同深度上的茎流速率存在差别,10 mm位点的茎流速率最大,20mm位点最小;不同方位的茎流速率是树干南侧最大,西侧次之,北侧最小.使用HOBO气象站同步测定各种气象因子,分析树干茎流日变化、日际变化及其与气象因子的关系,逐步回归分析表明:太阳有效辐射、气温和风速是影响茎流的主要气象因子.通过干预处理研究不同的抑制蒸腾措施对树干茎流的影响,结果表明喷抗蒸腾剂、摘叶和遮荫处理能有效地降低蒸腾耗水,但摘叶和遮荫处理的效果较为明显.  相似文献   

17.
Assessing and using tree species (exotic or native) with superior tolerance to environmental stresses (such as drought and high temperature) play an important role in afforestation practices. In the present study, stem sap flow characteristics and responses to ambient meteorological factors of three tree species, Albizzia kalkora (native), Azadirachta indica (exotic), and Acacia auriculaeformis (exotic), in a dry-hot valley (Yuanmou, Yunnan Province, China) were investigated using thermal dissipation probes. The diurnal dynamics of sap flow in three studied species displayed an obvious circadian rhythm during the wet and dry seasons, with the exception of A. indica during the dry season. The sap flow velocity (SFV) in A. kalkora and A. auriculaeformis was significantly positively correlated with photosynthetically active radiation (PAR), air temperature, vapour pressure deficit (VPD) and wind speed, but negatively correlated with atmospheric relative humidity over the two seasons. The cross-correlation analysis also revealed that the SFV of the three species was significantly correlated with PAR and VPD (P < 0.001). Additionally, stem sap flow lagged behind PAR but ahead of VPD, and the diurnal sap flow was more dependent on PAR than on VPD. However, we found that the dominant climatic factor influencing the stem sap flow differed between daytime and nighttime. PAR was more influential than other meteorological factors during the daytime, while VPD or other factors were more influential overnight. When the nighttime refilling ability of the three tree species was compared, our results suggest that A. indica has higher drought resistance and better for afforestation of the studied region.  相似文献   

18.
In this paper, we studied the nocturnal stem water recharge of Acacia mangium. It is helpful to improve the precision of canopy transpiration estimation and canopy stomatal conductance, and to further understand the lag time of canopy transpiration to stem sap flow. In this study, the whole-tree sap flow in an A. mangium forest was measured by using Granier’s thermal dissipation probe for over two years in the hilly land of South China. The environmental factors, including relative humidity (RH), precipitation, vapor pressure deficit (VPD), photosynthetically active radiation (PAR), and air temperature (T a) were recorded simultaneously. The stem water recharge of A. mangium was analyzed on both daily and monthly scales. Sap flux density was lower at night than during the day. The time range of nighttime sap flux density was longer in the dry season than in the wet season. The water recharging mainly occurred from sunset to midnight. No significant differences were observed among inter-annual nighttime water recharges. Nighttime water recharge had no significant correlation with environmental factors, but was well correlated with the diameter at breast height, tree height, and crown size. In the dry season the contribution of nighttime water recharge to total transpiration had significant correlations with daytime transpiration, total transpiration, VPD, PAR and T a, while in the wet season it was significantly correlated with daily transpiration and total transpiration. __________ Translated from Chinese Journal of Ecology, 2007, 26(4): 476–482 [译自: 生态学杂志]  相似文献   

19.
Contrary to the conventional theory of optimal stomatal control, there is substantial transpiration at night in many tree species, but the functional significance of this phenomenon remains uncertain. To investigate the possible roles of nocturnal transpiration, we compared and contrasted the correlations of both nocturnal and diurnal sap flow with a range of traits in 21 temperate deciduous tree species. These traits included soil water affinity, shade tolerance, cold hardiness, nitrogen concentration of tissues, minimum transpiration rate of excised leaves, growth rate, photosynthetic capacity, stomatal length and density, and the water potential and relative water content of leaves at the wilting point. Nocturnal sap flow was higher in species with higher leaf nitrogen concentrations, higher rates of extension growth and lower shade tolerances. Diurnal sap flow was higher in species with higher leaf nitrogen concentrations and photosynthetic capacities on a leaf area basis. Because leaf metabolism and dark respiration, in particular, are strongly related to leaf nitrogen concentration, our findings suggest that nocturnal transpiration functions to sustain carbohydrate export and other processes driven by dark respiration, and that this function is most important in fast- growing shade-intolerant tree species.  相似文献   

20.
For this paper, GREENSPAN sap flow system was used to monitor the dynamics of trunk sap flow of Gingkgo biloba. Results indicate that sap flow velocity is significantly different among different heights, depths, and directions of the trunk. Sap flow velocity at the upper position of the trunk is higher than that of the middle and lower position, but cumulative flux is not significantly different among the upper, middle and lower sections. Sap flow velocity at 10 mm reached the most and that at 20 mm the least. However, sap flow velocity at 5 mm and 15 mm was similar and was second among the four depths. Results also showed that sap flow velocity of the south was the highest, and that of the west was next. An Automatic Weather Station of HOBO was synchronously applied to measure these meteorological parameters, and the relationship between these parameters and the changes of trunk sap flow velocity were analyzed. We found that the change of sap flow velocity was a single-crest curve on clear days and multi-crest curve on cloudy and rainy days. In addition, it is also revealed that by stepwise regression analyses photosynthetical active radiation (PAR), temperature and wind speed are the main environmental factors affecting sap flow velocity. The efficient methods of reducing water transpiration of trees, including leaf pruning, overshadowing and antitranspirant spraying, were found by investigating the effects on inhibiting transpiration, which indicated that spraying of antitranspirants, leaf pruning and overshadowing could significantly reduce transpiration but the effects of leaf pruning and overshadowing were far better than that of antitranspirant spraying. Translated from Scientia Silvae Sinicae, 2006, 42(5): 22–28 [译自: 林业科学]  相似文献   

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