Paper Info
Title
Monitoring the Invasion of Spartina alterniflora Using Multi-source High-resolution Imagery in the Zhangjiang Estuary, China.
Abstract
Spartina alterniflora (S. alterniflora) is one of the most harmful invasive plants in China. Google Earth (GE), as a free software, hosts high-resolution imagery for many areas of the world. To explore the use of GE imagery for monitoring S. alterniflora invasion and developing an understanding of the invasion process of S. alterniflora in the Zhangjiang Estuary, the object-oriented method and visual interpretation were applied to GE, SPOT-5, and Gaofen-1 (GF-1) images. In addition, landscape metrics of S. alterniflora patches adjacent to mangrove forests were calculated and mangrove gaps were recorded by checking whether S. alterniflora exists. The results showed that from 2003-2015, the areal extent of S. alterniflora in the Zhangjiang Estuary increased from 57.94 ha to 116.11 ha, which was mainly converted from mudflats and moved seaward significantly. Analyses of the S. alterniflora expansion patterns in the six subzones indicated that the expansion trends varied with different environmental circumstances and human activities. Land reclamation, mangrove replantation, and mudflat aquaculture caused significant losses of S. alterniflora. The number of invaded gaps increased and S. alterniflora patches adjacent to mangrove forests became much larger and more aggregated during 2003-2015 (the class area increased from 12.13 ha to 49.76 ha and the aggregation index increased from 91.15 to 94.65). We thus concluded that S. alterniflora invasion in the Zhangjiang Estuary had seriously increased and that measures should be taken considering the characteristics shown in different subzones. This study provides an example of applying GE imagery to monitor invasive plants and illustrates that this approach can aid in the development of governmental policies employed to control S. alterniflora invasion.
Year
DOI
Venue
2017
10.3390/rs9060539
REMOTE SENSING
Keywords
Field
DocType
remote sensing,Google Earth,invasive species,smooth cordgrass,object-oriented method,landscape metrics
Aquaculture,Ecology,Invasive species,Mangrove,Visual interpretation,Spartina alterniflora,Estuary,Land reclamation,Geology
Journal
Volume
Issue
ISSN
9
6
2072-4292
Citations 
PageRank 
References 
3
0.42
6
Authors
7
Name
Order
Citations
PageRank
Mingyue Liu141.87
Huiying Li252.46
Lin Li34911.35
Weidong Man431.78
Mingming Jia536641.64
Zongming Wang67219.71
Chunyan Lu731.44