利用 SPAD-502对高山杜鹃氮素营养的快速诊断研究

利用SPAD-502型叶绿素计测定了不同氮水平下高山杜鹃不同生长时期、不同叶位的SPAD 值,分析SPAD值与叶绿素含量和叶片总氮含量的关系。结果表明,不同生长期第1轮和第2轮叶片的SPAD值与叶绿素含量均呈显著线性正相关,其中新梢生长期第1轮叶片的SPAD值与叶绿素含量的相关性最强,而叶绿素各参数中对SPAD值影响最大的是叶绿素b的含量。在不同氮水平下, SPAD值及相对叶色差与单位干重的总氮含量具有显著线性正相关关系, SPAD值的变化能够反映60％的单位干重叶氮含量的变化。因此,可以利用SPAD-502型叶绿素计对高山杜鹃进行快速、无损的氮素营养诊断。     

SPAD叶绿素仪在评价树木叶片光环境和健康水平上的应用初探

树木叶片叶绿素含量的消长规律是反映叶片生理活性变化的重要指标之一。以健康白桦和受虫害加拿大杨为实验材料,利用SPAD-502叶绿素仪对其进行叶绿素相对含量测定,并结合相应的生长光照条件和病虫害程度进行分析,探索SPAD值在响应叶片光环境和健康水平方面的能力。研究结果表明,利用SPAD-502叶绿素仪对阔叶树种的光环境及叶片健康水平进行评价是可行的,如能同时结合其它检测手段和方法,则更能保证评价的准确度。     

云南咖啡主要种植区咖啡树SPAD值比较及气候相关分析

运用叶绿素仪(SPAD-502)在云南保山、德宏、临沧和普洱等4个主要咖啡产区进行叶绿素测定,并与当地气候因素进行相关分析。结果显示,保山和临沧SPAD值无显著差异(P0.05),其他各区域SPAD值均有极为显著的差异(P0.01),SPAD值最高为普洱(70.55),最低为德宏(60.77),云南地区SPAD值与气候因子无显著的相关性(P0.05)。本研究为叶绿素仪(SPAD-502)在咖啡树上的应用提供了一定的科学依据。     

杨树叶片SPAD值与叶绿素含量的相关性研究

采用SPAD-502叶绿素仪与分光光度法分别测定了杨树叶片的SPAD值与叶绿素含量,建立SPAD值与叶绿素a、叶绿素b和总叶绿素的线性函数、乘幂函数、指数函数及对数函数的拟合方程,并根据决定系数(R2)确定最佳拟合曲线,以探讨SPAD值与叶绿素含量之间的关系。结果表明:杨树叶片SPAD值与叶绿素a、叶绿素b及总叶绿素含量间均存在极显著正相关关系。SPAD值与叶绿素a含量的最优函数模型为y=0.004 219SPAD1.630 2(R2=0.918 7);SPAD值与叶绿素b含量最优函数模型为y=0.071 308e0.055 468SPAD(R2=0.927 9);SPAD值与叶绿素总量的最优函数模型为y=0.003 24SPAD1.792 1(R2=0.924 3)。通过对9个不同品种叶片SPAD值与叶绿素含量实测值与预测值的统计检验发现,叶绿素a与总叶绿素含量的实测值与预测值间不存在显著差异,可以通过回归方程来预测杨树叶片叶绿素的绝对含量。     

风吹楠与大叶风吹楠的叶绿素含量比较研究

以从云南省西双版纳州、德宏州和临沧市的5个县收集保存的风吹楠和大叶风吹楠为材料,采用便携式叶绿素仪(SPAD-502)和分光光度计测定风吹楠和大叶风吹楠叶片SPAD值与叶绿素含量并进行比较分析。结果表明,风吹楠6个家系90株1 350片叶的SPAD值变幅为51.00~82.00,总叶绿素含量在6个家系间的变幅为2.11~3.75 mg/g,家系间差异达到极显著水平(P0.01);大叶风吹楠4个家系60株900片叶的SPAD值变幅为48.00~72.00,总叶绿素含量在4个家系间的变幅为1.79~2.59 mg/g,家系间差异达到极显著水平(P0.01)。共10个家系150株的SPAD值与叶绿素a、叶绿素b和总叶绿素含量的相关性达到显著正相关(P0.05)或极显著正相关(P0.01),可用便携式叶绿素仪(SPAD-502)来估测叶绿素含量。风吹楠与大叶风吹楠的SPAD值和叶绿素含量存在明显的种间差异。     

灵石山米槠林优势种不同叶龄叶绿体色素沿海拔梯度的变化

对灵石山米槠林优势种不同叶龄叶绿体色素的差异以及优势种叶绿体色素沿海拔梯度的变化规律进行分析。结果表明:除少数优势种在某海拔梯度以外,不同叶龄叶绿素a、叶绿素b和叶绿素(a+b)存在显著或极显著差异,一般在中高海拔梯度差异最大,且2年生叶片含量高于1年生叶片;而不同叶龄间叶绿素a/b和类胡萝卜素的差异性表现复杂,表现了植物对环境的适应。不同优势种叶绿素[叶绿素a、叶绿素b和叶绿素(a+b)]在海拔梯度间存在显著差异,并且沿海拔梯度的变化呈现一定的规律性,米槠林优势种中有7种优势种不同叶龄叶绿素[叶绿素a、叶绿素b、叶绿素(a+b)]含量均随海拔的升高先升高,一般在A5(442m)或A6(531m)达到最大值,然后随海拔的升高逐渐降低,而叶绿素a/b随海拔升高变化趋势比较多样化。类胡萝卜素作为功能色素由于其功能比较复杂,对海拔的响应规律也不尽相同。海拔作为重要的环境因素对于植物叶绿体色素产生显著影响,不同的优势种沿海拔的变化规律存在差异,说明其对环境的适应对策不同。     

SPAD-502型叶绿素计在估测大面积区域叶绿素含量中的应用

在每株树木中摘取其上、中、下三部分的叶片,每部分选取5～10片叶子进行测定,对每片叶子的6处不同部位进行SPAD值测定,然后取其平均值作为此片叶子的最终SPAD值,再对所有叶片SPAD值取平均值作为树木的SPAD值。利用GPS技术使树木有了空间信息,并于遥感图像能够结合起来进行分析,为估测大面积区域叶绿素含量创造可能性。结果表明,SPAD-502型手持式测定仪携带方便,测定简单迅速,不损害植被,与GPS技术及遥感反演技术相结合,能简便估测大面积区域叶绿素含量。     

不同油茶无性系叶绿素相对含量及其分布

运用SPAD-502叶绿素仪,对来自江西、浙江和福建的9个不同油荼无性系的叶绿素相对含量进行测定.结果表明:不同油茶无性系的叶片叶绿素相对含量差异极显著,PN7的叶绿素相对含量最高,同为福建省当地无性系的△51-2和○65-7的值明显偏低.不同油茶无性系叶片多以叶基部的叶绿素相对含量最高,叶尖部最低.每个无性系不同节位叶片叶绿素相对含量大小顺序不统一,植株中部叶的叶中部位叶绿素相对含量的标准误相对较低,比较稳定,可作为叶绿素相对含量的最佳测定部位.     

10种园林树木叶绿素与SPAD值相关性研究

通过测定10种常见园林树木叶片的叶绿素含量及叶片的SPAD值,探讨了SPAD值与叶绿素含量之间的关系。试验表明,园林树木叶片中叶绿素含量与SPAD值显著相关,且各自表现为不同的相关函数模型。     

便携式测定仪在测定叶片衰老过程中氮和叶绿素含量上的应用

选取哈尔滨地区本地植物华北紫丁香和山槐,以及华北引进种紫穗槐为研究材料,于2003年秋季对3种植物叶片从夏末叶片盛期到秋末叶片脱水变干脱落全过程进行了连续测定.结果表明:1)2种仪器对于表征单位叶面积上叶绿素和N含量的有效性明显高于表征单位鲜质量上叶绿素和N含量.2)尽管PPW-3000和SPAD-502对于表征单位叶面积N含量和各种叶绿素含量具有一定的普适性(R2=0.51～0.65),但不能有效表征不同植物的种间差异性.因此,使用2种便携式测定仪准确估计N和叶绿素含量需要首先确定每种植物的标准校正曲线.3)当表征同一种植物不同生长时期叶绿素和N含量变化时,2种仪器都适用于表征本地种华北紫丁香和山槐叶片衰老过程的变化(R2＞0.82);而对于外地引进种紫穗槐,叶片衰老脱水过程中叶绿素并未同时分解,表征效果欠佳(R2＜0.66),甚至相关性不显著.可见,便携式仪器更适用于适应本地气候的正常衰老种的相关测定.4)2种仪器比较而言,PPW-3000对于表征叶片N含量变化,尤其是对于叶片衰老脱水过程叶绿素并未同时分解的叶片(如紫穗槐),效果较SPAD-502好;而对于叶片衰老过程中叶绿素同时降解的叶片(如华北紫丁香和山槐),2种仪器效果没有明显区别.     

3种木兰科植物叶片SPAD值的分布特征及其与叶绿素含量的关系

为探讨3种木兰科植物灰木莲Manglietia glauca、醉香含笑Michelia macclurei和乐昌含笑Michelia chapensis叶片SPAD值的分布特征及其与叶绿素含量之间的关系,采用SPAD叶绿素计和分光光度法分别测定了三者叶片SPAD值和叶绿素含量.结果表明:3种植物叶片SPAD值的差异主要...     

Evaluating Beech Tree Phenology in a Deciduous Broadleaf Forest in Northern Iran Using Ground Observation and MODIS Images

We selected 15 beech trees (Fagus orientalis) from the study area in a mountainous region from 520 to 1310 m above sea level. Ground observations of the beech tree growth process from January to December 2004 in 7- to 15-day intervals were performed both visually and by measuring leaf chlorophyll concentration (chlorophyll meter SPAD-502). Results for the regression analysis showed that the leaved period positively correlated with the air temperature (r?=?.894). Anthesis and SPAD measurements have a negative relationship with air temperature and as temperature increases they appear earlier in the year. Anthesis and SPAD measurements had correlation coefficients of r?=??.883 and r?=??.855, respectively. The anthesis and bud bursting and leaf tip appearance have a negative relationship with increasing altitude from sea level and as altitude increases they appear later in the year. To make phenological events in deciduous broadleaf forests recognizable, we used a seasonal 8-day composite Moderate Resolution Imaging Spectroradiometer/Normalized Difference Vegetation Index (MODIS/NDVI). Prior to leaf expansion, NDVI increased from the 109th day of the year or earlier. Existence of the evergreen plants (Ruscus hyrcanus) on the ground and snow-melting exert an influence on inconsistency of phenology monitoring of MODIS/NDVI images. Regression analysis showed that there is a positive relationship between NDVI and SPAD measurements (chlorophyll content) in beech trees.     

Evaluation of a portable chlorophyll meter to estimate chlorophyll and nitrogen contents in sugar maple (Acer saccharum Marsh.) leaves

Portable, non-destructive chlorophyll meters could be a valuable tool for forest managers and researchers. The ability of such meters to assess both chlorophyll and nitrogen content has been well established for many agricultural species, but not well-studied for North American forest tree species. The objective of this study was to evaluate the ability of a portable chlorophyll meter to estimate chlorophyll (CHL) and nitrogen (N) content in sugar maple (Acer saccharum Marsh.) leaves by testing correlations between chlorophyll content index values (CCI) and extractable CHL and N in large heterogeneous samples. Significant correlations were observed between CCI and CHL (P ≤ 0.001, r² = 76%) and CCI and N (P ≤ 0.001, r² = 64%). These data indicate that the meter tested can be an effective tool for estimating relative chlorophyll and nitrogen content in sugar maple leaves.     

葡萄叶片SPAD值与测定位置及光合色素含量的关系

为了实时、准确、无损地检测葡萄叶片中叶绿素的含量水平,以评价葡萄生长发育与营养状况,确保栽培的科学和施肥的合理,以‘夏黑’‘巨玫瑰’‘户太8号’‘阳光玫瑰’‘金手指’‘摩尔多瓦’这6个品种葡萄叶片为试验材料,采用叶绿素测定仪测定了6个葡萄品种叶片不同位置的SPAD值,使用分光光度计测定了葡萄叶片光合色素含量,探寻了葡萄叶片SPAD值的最适测量位点,分析了SPAD值与光合色素含量的关系,并建立了SPAD值与光合色素含量的线性函数拟合方程。结果表明:6个品种葡萄叶片的SPAD值,叶片顶部的均最高,中部的均次之,基部的均最小;其中,葡萄叶片中部的SPAD值最具有代表性。6个品种葡萄叶片的SPAD值与叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量均显著相关,其与叶绿素a含量的相关性最高;在不同品种葡萄叶片的SPAD值与叶绿素a、叶绿素总含量、类胡萝卜素含量的线性函数拟合方程中,‘户太8号’的拟合方程决定系数值最高,其叶绿素a、叶绿素总含量、类胡萝卜素含量的决定系数值分别为0.903 5、0.867 2、0.749 9;在叶绿素b与葡萄叶片SPAD值的拟合方程中,‘金手指’的拟合方程为y=0.034 7x-0.084 0,其决定系数R2值(0.773 4)最高。单一品种葡萄叶片的SPAD值与光合色素含量的回归模型的拟合准确率比6个葡萄品种汇总拟合回归模型的要高。     

松华坝水库天然林植物多样性调查研究

根据松华坝水库天然林群落的不同海拔梯度以及不同坡向设置36个典型样方进行调查。对松华坝水库物种组成、种子植物区系、群落各层次物种的重要值以及植物多样性进行分析。结果表明：调查到维管植物300种;乔木层云南松种群占绝对优势;水库天然林从乔木到灌木再到草本,植物多样性水平递增;随着海拔的上升,植物多样性水平先升高再降低;从阳坡到半阴坡再到阴坡,植被多样性水平先升高再降低。     

Can soil plant analysis development values predict chlorophyll and total Fe in hybrid poplar?

Iron chlorosis caused by an elevated soil pH remains an important selection criteria in evaluating hybrid Populus trials in northwest New Mexico. Compared to expensive extraction methods or visual ranking scales, the soil plant analysis development (SPAD) chlorophyll meter is a handheld tool that objectively indicates leaf color. SPAD calibration curves pertaining to Fe status in Populus leaves were developed for two clones: NM-6 (Populus nigra × Populus maximowiczii) and OP-367 (Populus deltoides × Populus nigra). Hybrids were grown in the greenhouse in a sandy loam soil of pH > 8 and the same soil amended with composted biosolids enriched with 420 mg kg⁻¹ Fe. SPAD measurements related to foliar Fe as follows: r ² = 0.72 for NM-6 and r ² = 0.58 for OP-367. SPAD measurements correlated with total chlorophyll as follows: r ² = 0.66 for NM-6 and r ² = 0.85 for OP-367. Based on the total chlorophyll content (supported with foliar element data), Fe sufficiency threshold values from SPAD measurements were estimated in these two clones.     

Growth and productivity of black spruce in even- and uneven-aged stands at the limit of the closed boreal forest

The increasing commercial interest and advancing exploitation of new remote territories of the boreal forest require deeper knowledge of the productivity of these ecosystems. Canadian boreal forests are commonly assumed to be evenly aged, but recent studies show that frequent small-scale disturbances can lead to uneven-aged class distributions. However, how age distribution affects tree growth and stand productivity at high latitudes remains an unanswered question. Dynamics of tree growth in even- and uneven-aged stands at the limit of the closed black spruce (Picea mariana) forest in Quebec (Canada) were assessed on 18 plots with ages ranging from 77 to 340 years. Height, diameter and age of all trees were measured. Stem analysis was performed on the 10 dominant trees of each plot by measuring tree-ring widths on discs collected each meter from the stem, and the growth dynamics in height, diameter and volume were estimated according to tree age. Although growth followed a sigmoid pattern with similar shapes and asymptotes in even- and uneven-aged stands, trees in the latter showed curves more flattened and with increases delayed in time. Growth rates in even-aged plots were at least twice those of uneven-aged plots. The vigorous growth rates occurred earlier in trees of even-aged plots with a culmination of the mean annual increment in height, diameter and volume estimated at 40–80 years, 90–110 years earlier than in uneven-aged plots. Stand volume ranged between 30 and 238 m³ ha⁻¹ with 75% of stands showing values lower than 120 m³ ha⁻¹ and higher volumes occurring at greater dominant heights and stand densities. Results demonstrated the different growth dynamics of black spruce in single- and multi-cohort stands and suggested the need for information on the stand structure when estimating the effective or potential growth performance for forest management of this species.