为了鄱阳湖湿地的生态安全,通过土壤盆栽实验,研究了不同Cu浓度(0、50、100、150、200和300 mg/kg)下灰化苔草(Carex cinerascens)在整个生长发育期内叶片光谱参数和叶绿素的变化过程。结果表明,灰化苔草对Cu的耐性上限浓度不超过300 mg/kg;随着添加Cu浓度的升高,叶片Cu含量和土壤有效态Cu含量均逐渐升高,叶片SPAD值渐次降低;叶片Cu含量与红谷深度、红边峰值、红边斜率、R750-1250 nm等光谱特征值之间均呈现显著的负相关关系;灰化苔草最佳监测生育期为生长期。由此,为鄱阳湖湿地生态健康变化进行快速诊断提供了科学依据。
Carex cinerascens( C. cinerascens),a dominant plant,is widely distributed in the Poyang Lake area. Through planting with pots experiment,the change of chlorophyll and spectral parameters of C. cinerascens leaves was studied under the different levels of copper( 0,50,100,150,200 and 300 mg / kg) during its whole growing period. The results showed that the tolerance limit of C. cinerascens for Cu concentration was not more than 300 mg / kg. With the increase of adding Cu concentration,Cu content in the leaf of C. cinerascens and in the soil( available content) inereased,conversely,the SPAD value,whose on behalf of the chlorophyll content,reduced gradually. There were some significant negative correlations between the Cu content in the leaf and the depth of Red Valley,the peak value of Red Edge,the Red Edge Slope,the R750- 1250 nm. Meanwhile,the spectral parameters in growing stage was found more sensitive than those in two other periods,seeding stage and flowering stage. So growing season was the best monitoring growth period. Based on those results,the article could offer a scientific basis for rapid diagnosis on changes in Poyang Lake wetland ecological health.