Design of a Web Crawler for Water Quality Monitoring Data and Data Visualization

Many countries are paying more and more attention to the protection of water resources at present,and how to protect water resources has received extensive attention from society.Water quality monitoring is the key work to water resources protection.How to efficiently collect and analyze water quality monitoring data is an important aspect of water resources protection.In this paper,python programming tools and regular expressions were used to design a web crawler for the acquisition of water quality monitoring data from Global Freshwater Quality Database(GEMStat)sites,and the multi-thread parallelism was added to improve the efficiency in the process of downloading and parsing.In order to analyze and process the crawled water quality data,Pandas and Pyecharts are used to visualize the water quality data to show the intrinsic correlation and spatiotemporal relationship of the data.

Evidence of return of chum salmon released from Tangwang River by strontium marking method

In order to assess the effect of enhancement release of chum salmon(Oncorhynchus keta),otolith strontium(Sr)marking method was used to tag chum salmon released in Tangwang River in 2016.The homing chum salmon were detected and the samples were collected in Tangwang River,Ussuri River and Suifen River in the autumn of2018.The samples were analyzed by examining Sr and calcium(Ca)fingerprints in the otolith using electron probe microanalysis.The results suggested that two samples collected in Tangwang River had the marking ring near the core of otolith where the Sr concentration and Sr/Ca ratio were significantly higher than comparative samples.Proving that the two fish belonged to the released population in Tangwang River in 2016.This article indicated the success of the enhancement release of chum salmon from the Tangwang River for the first time and also confirmed the validity of Sr marking in enhancement release of fishes.

The Geographical Rotation of Local Officials and Enterprise Cross-city Mergers and Acquisitions in China

The economic impact of the geographical rotation of local officials is important in China's official management system.This study used a zero-inflated Poisson regression model and found that the geographical rotation of local officials significantly increased cross-city mergers and acquisitions(M&As)of enterprises.The impact of local officials'geographical rotation on M&As was more pronounced under certain conditions.These conditions included:(i)when officials were transferred from cities with a higher development level to cities with a lower development level;(ii)when the outflow cities were municipalities directly governed by the central government,provincial capitals,or separately listed cities;(iii)when the transfers of officials occurred within the same province;(iv)when the transfers took place before 2012;and(v)when the transfers happened in the years following significant central government conferences,which provided strong political incentives for M&As.