Monitoring Method And Application Of Reclamation Process Based On Long Time Series Remote Sensing Observations

At present,reclamation—changing ocean areas into inland land cover types for human usage—is one of the major methods for expanding land areas around the world to alleviate the problem of land shortage.Thus,reclamation activities play an important role in land area extension.In recent years,reclamation projects have been active in China.However,research on how to determine the initiation of reclamation activity remains very limited.At present,the supervision of the area of reclamation activities can only stay for a long period of regional monitoring within five to ten years,while the monitoring of the time of reclamation activities is extremely scarce.Also,the relevant departments of ocean management have released several documents to strengthen the control of reclamation activities in recent years.In this situation,this paper summarizes the main problem of reclamation activities tracking: First,the accuracy of existing monitoring of reclamation activities is insufficient.Second,a small number of existing researches on reclamation activities are carried out only based on land cover changes in a long period of time,and remote sensing satellite images of long time series are not used.As a result,the monitoring accuracy of existing reclamation activities in the temporal dimension is limited to the monitoring of reclamation areas within 5 or even 10 years.Last,existing research on reclamation activities cannot successfully and effectively monitor the specific beginning time and end time of reclamation activities,and specific monitoring and analysis of the progress of reclamation projects cannot be realized only through the active areas of reclamation activities in a long period of time.In this situation,this paper uses Landsat remote sensing observations to construct a reclamation activity tracker.This research results include effective monitoring of reclamation area,high precision monitoring of reclamation period,validation of generalization and robustness of reclamation tracker in large scale area,and analysis of influential factors of tidal research in Chinese coastal reclamation area with multi-tidal properties.The details are listed as follow:(1)Monitoring of various types of reclamation activities.Detailed analysis of the representation of reclamation activities on remote sensing observations.Combined supervised and unsupervised classification methods to classify the remote sensing observations in high efficiency and high precision way.The multi-level detection method and eight-neighborhood boundary extraction method are separately used for different types of reclamation activities.Successfully monitored the two types of reclamation activities.(2)Construction of high-precision tracker for whole-process of reclamation activities.Based on the location and monitoring results of the reclamation activity area,combined with the features of remote sensing observation of long time series,analyze the signal of the reclamation activities.For the sea enclosure reclamation,the end time of the activity is tracked by using the method of water boundary comparison in long-time series.For the sea fill reclamation,the frequency transformation method is proposed to quantify the signal of reclamation activities.Based on the quantified signal,this paper established a logical framework to track the beginning and end time of reclamation activities.Merge two tracking methods for two types of reclamation activities,construct the reclamation period tracker.Track the reclamation activities successfully in pixel level with high temporal resolution.(3)Large-scales area application of reclamation activity tracker and multi-angle analysis of reclamation activity process.Hangzhou Bay and Shenzhen Port,two large-scale areas were selected to track and monitor the reclamation activities using the constructed reclamation tracker to verify the generalization and robustness of the tracker.Reclamation activities have been successfully monitored with 99% and 96% accuracy and with high time accuracy of over65%.For the selected typical reclamation areas in two large-scale areas,conclude the advantages and disadvantages by comparing with the result of the traditional reclamation monitor method.Analyze the reclamation tracker result of the typical areas in multi-angle,demonstrate the application value of the reclamation tracker.(4)Analyze the influence of multi-tidal areas on the reclamation activities.Based on the four tidal types of the location,this study respectively chose four typical cases of reclamation to analyze the correlation with tidal factors.By comparing and analyzing the tracking results of reclamation activities in different tidal properties,it is verified that the reclamation activity tracker proposed in this paper is not seriously affected by the interference of various tidal properties.And the tidal type will affect the reclamation activities.There are more long-term reclamation activities in semi-diurnal areas,and there are more rapid reclamation activities in regular semi-diurnal tides and regular diurnal tides area.