不同草坪草冠层反射光谱特征的比较研究

选用高羊茅、多年生黑麦草、草地早熟禾、狗牙根、匍匐翦股颖5种草坪草的24个品种为试验对象,测定冠层反射光谱,比较可见光和近红外区域反射率的差异性,分析多种红边参数与草坪色泽目测评分值之间的相关性。结果表明,高羊茅8个品种在450～900 nm的反射率无显著性差异;草地早熟禾5个品种可见光450～650 nm的反射率存在差异显著性(P<0.05);多年生黑麦草8个品种在近红外750～900 nm的反射率存在差异显著性(P<0.01)。高羊茅美洲虎、多年生黑麦草威士、草地早熟禾蓝宝石、狗牙根太阳城、匍匐翦股颖普特在550、565、8008、50 nm处均表现出差异显著性(P<0.05),红边斜率与草坪色泽目测评分值之间存在显著相关关系。利用高光谱分析技术可以快速、准确地反演草坪冠层叶绿素含量,并且能够区分同一草坪草种品种间的反射率差异。

Comparison study on canopy reflection spectrum characters of different turfgrasses

Twenty four cultivars of five turfgrass species,which were commonly used to establish golf or sports field in southern China,were selected to study the reflection difference of visible light and near infrared by determining the canopy reflection spectrum in September,2009.Results showed that no significant difference in canopy reflectance between 8 tall fescue cultivars,but significant differences were detected between 5 Kentucky bluegrass cultivars（P〈0.05）and between 8 perennial ryegrass cultivars（P〈0.01）.There were significant differences in canopy reflectance between 5 turfgrass species in most parts of visible range and near infrared range,both perennial ryegrass（Whisk）and creeping bentgrass（Putter）had significantly higher canopy reflectance at 550 nm and 565 nm compared with Kentucky bluegrass（Sapphire）,bermuda grass（Sun City）,and tall fescue（Jaguar）.At 800 nm and 850 nm,creeping bentgrass（Putter）had the highest reflectance,and the differences between 5 turfgrass species reached significant（P〈0.05 or P〈0.01）.A close correlation relationship was detected between red-edge slope of 5 cultivars and their color visual rating.Hyperspectral analysis technology can be used to estimate the chlorophyll content of turf canopy as well as to detect the spectral differences between cultivars.