Bermudagrass Seasonal Responses to Nitrogen Fertilization and Irrigation Detected Using Optical Sensing
Bermudagrass Seasonal Responses to Nitrogen Fertilization and Irrigation Detected Using Optical Sensing
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使用光学传感检测狗牙根对氮肥和灌溉的季节性反应
DOI：
10.2135/cropsci2006.06.0400
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
B. Martin
中科院分区：
文献类型：
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作者：
X. Xiong;G. E. Bell;J. Solie;M. W. Smith;B. Martin
本研究的目的是评估狗牙根响应氮肥和灌溉的季节性差异，通过使用光学传感。第二个目标是确定当草坪对N的响应被水分状况的差异所混淆时，光学传感是否可以测量N状况。狗牙根（Cynodon dactylon L.）“里维拉”和“育空地区”在2003年和2004年的生长季节进行了管理下的三个灌溉处理和六个N处理。测定了草坪质量、归一化植被指数（NDVI）、绿色归一化植被指数（GNDVI）、红光反射率与近红外反射率的关系（R/NIR）和绿色光反射率与近红外反射率的关系（G/NIR）。供氮和灌水处理对稗草生长的影响呈现明显的三次多项式季节变化趋势，表现为早、盛、中、晚四季响应。归一化植被指数和GNDVI比R/NIR和G/NIR更能反映草坪质量和氮素状况。四个指数之间的比较表明，植被指数与灌溉，氮肥和草坪质量更密切相关。最低可接受的和目标的植被指数的基础上制定的视觉草坪质量评估的季节性。研究还发现，NDVI响应氮肥灌溉处理的影响并不强烈，可以作为一个指标的N的状态和需要，无论灌溉处理。
The objective of this study was to evaluate seasonal differences in bermudagrass response to N fertilization and irrigation by using optical sensing. A second objective was to determine if optical sensing could measure N status when the turf response to N was confounded by differences in moisture status. Bermudagrasses (Cynodon dactylon L.) 'Rivera' and 'Yukon' were managed under three irrigation treatments and six N treatments during the growing seasons in 2003 and 2004. Turf quality, normalized difference vegetation index (NDVI), green normalized difference vegetation index (GNDVI), red light reflectance in relation to near infrared reflectance (R/NIR), and green light reflectance in relation to near infrared reflectance (G/NIR) were measured. Bermudagrass demonstrated a noticeable third-order polynomial seasonal trend in response to N and irrigation treatment, and this trend was characterized as early-, peak-, mid- and late-season responses. Normalized difference vegetation index and GNDVI demonstrated a better relationship with turf quality and N status than R/NIR and G/NIR. A comparison among the four indices showed NDVI to be more closely correlated with irrigation, N fertilization, and turf quality. Minimum acceptable and target NDVI were developed by seasonal period based on visual turf quality assessment. It was also found that NDVI response to N fertilization was not strongly affected by irrigation treatment and could be used as an indicator of N status and need regardless of irrigation treatment.