Back to Search Start Over

Novel indicator for assessing wetland degradation based on the index of hydrological connectivity and its correlation with the root-soil interface.

Authors :
Zhang, Yinghu
Chen, Jinhong
Zhang, Jinchi
Zhang, Zhenming
Zhang, Mingxiang
Source :
Ecological Indicators. Dec2021, Vol. 133, pN.PAG-N.PAG. 1p.
Publication Year :
2021

Abstract

• The index of hydrological connectivity (IHC) changed both spatially and temporally. • The spatial distribution of high IHC has been extremely fragmented since 2010. • IHC could be treated as a novel indicator of the status of wetland degradation. • Soil property had larger influences on IHC than roots systems at root-soil interface. In this study, an innovative method was used to assess the spatial and temporal patterns of the hydrological connectivity in soil profiles in the Yellow River Delta wetland. In this method, field dye-tracing experiments conducted in the study area (i.e., large [LWa] and small communities [LWb] of Phragmites australis and Suaeda glauca [JP]) were considered, and the root-soil interface in the region and the status of the wetland degradation were analyzed. The results revealed that the index of hydrological connectivity (IHC) significantly changed both spatially and temporally. The high IHC values reaching a 0.392 ± 0.209 gradient were concentrated in the middle and western parts of the study areas. The spatial distribution of the high hydrological connectivity has been extremely fragmented since 2010. The LWb (severely degraded wetland) and JP (extremely degraded wetland) were found to be more seriously degraded than the LWa (moderately degraded wetland) in the study area. The changes in the IHC were positively correlated with the principal component (PC) values of the wetland degradation. The IHC is a novel indicator of the status of wetland degradation. Furthermore, the soil holding capacity, soil non-capacity porosity, and soil ventilation were relatively important for the changes in the IHC. Compared with the soil properties, the hydrological responses of the roots systems can be neglected at the root-soil interface. Based on our results, we propose an alternative wetland restoration solution for the Yellow River Delta wetland: 1) a seepage layer in the surface soils (0–10 cm), shallow ploughing treatment, and litter or straw return to the soil surface should be conducted to increase the hydrological connectivity of the soil surface; 2) reeds should not be reaped every year to remove the nutrients from this area; and 3) appropriate freshwater inputs should be strengthened. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
1470160X
Volume :
133
Database :
Academic Search Index
Journal :
Ecological Indicators
Publication Type :
Academic Journal
Accession number :
154243686
Full Text :
https://doi.org/10.1016/j.ecolind.2021.108392