Spatial and temporal characteristics of harmful algal blooms in Zhejiang Province waters during 1933–2018

ABSTRACT

Harmful algal bloom (HAB) data included events caused by toxic species and non-toxic species, and was collected from red tide outbreaks in the Zhejiang Province coastal waters during 1933–2018. The geostatistical tools in Geographic Information System (GIS) were used to analyse the spatial and temporal distributions of these red tide events and map the distribution of these events in the study area. The results show that: (1) three areas had very-high frequency of red tide: Shengshan waters, Eastern waters of Zhujiajian and Nanji Islands waters. (2) The red tide occurrences exhibited significant seasonality: May is the most likely time for a red tide outbreak in Zhejiang waters. (3) Prorocentrum donghaiense occurred 182 times, Karenia mikimotoi occurred 64 times and Skeletonema costatum occurred 59 times in the total events. Prorocentrum donghaiense and Karenia mikimotoi are the algae species that are most prone to forming red tides in Zhejiang waters. This study utilized a visual approach to identify the scope, distribution and characteristics of red tide in the Zhejiang Province coastal waters over the past 85 years more fully, thus providing useful information to support the monitoring and management programme for HABs.

KEYWORDS:

• Spatial characteristics
• temporal characteristics
• harmful algal blooms (HABs)
• GIS
• Zhejiang Province waters

Acknowledgement

The authors would like to thank people from collaborating departments for assistance in data compilation, analysis and interpretation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Author contribution statement

WS and ST conceived the idea and designed the experiments. WS and LF performed the experiments. WZ, LF, LD, LN analysed the data. WS, LN wrote the manuscript; other authors provided editorial advice.

Declaration of interest statement

The authors declare that we have no financial and personal relationships with other people or organization that can inappropriately influence our work, there is no professional or other personal interests of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled.

Additional information

Funding

This research was supported by the National Key Research and Development Program of China (No.2017YFC1404300), the National Natural Science Foundation of China (No. 41371494).