Research On The Impact Of Wind Power Projects On The Marine Ecological Environmen

In recent years,with China ’s vigorous promotion of wind energy resource development,wind power installed capacity has grown rapidly.Compared with onshore wind power,offshore wind power has obvious advantages in terms of resources and power generation efficiency,and its development prospects are broader.However,the development of large-scale and dense offshore wind resources will inevitably affect the marine ecological environment.Therefore,it is necessary to carry out research on the environmental effects of offshore wind power projects,aiming to provide reference for the realization of regional ecological,economic and social sustainable development and ’ double carbon ’ strategy.Based on the framework of scenario analysis,combined with geographic information technology(GIS)and mathematical model,this paper studies the impact of an offshore wind farm in Rudong,Jiangsu Province on the marine ecological environment before,during and after the construction of the station.The specific conclusions are as follows :(1)The change of water quality in the study area is obvious.The concentrations of chemical oxygen demand(COD),petroleum,copper,cadmium,mercury,zinc and arsenic in seawater were in accordance with the first class of ’ Seawater Quality Standard ’(GB3097-1997)from the beginning of the station to the operation period.However,inorganic nitrogen,phosphate and lead exceeded the standard,among which inorganic nitrogen exceeded the standard most seriously.In most stations,inorganic nitrogen exceeded the fourth standard,while other exceeding factors met the second and third standards.Before the station was built,the concentrations of COD,copper and arsenic were the highest.During the project period,the concentrations of petroleum,inorganic nitrogen,phosphate,cadmium and mercury were the highest.During the operation period,the concentrations of zinc and lead were the highest.The water quality evaluation results show that the water quality is relatively clean before the construction of the station and during the operation period,while there is mild pollution during the construction period.The study of water eutrophication found that the seawater was in a state of mild eutrophication in each period.From the perspective of heavy metal pollution level,the pollution level before the construction and operation period is in a state of alert,and there is mild pollution during the construction period.(2)The sediment quality in the study area changed little.From the establishment of the station to the operation period,the indicators of seawater are in line with the first category of the ’ Sediment Quality Standard ’(GB18668-2002).Before the construction of the station,the contents of total organic carbon,mercury and arsenic were the highest.During the project period,the contents of petroleum and cadmium were the highest.During the operation period,the contents of zinc,copper and lead were the highest.From the results of sediment evaluation,the sedimentary environment of each period is in a clean state.From the perspective of heavy metal pollution level,the pollution level in each period is relatively slight.(3)The change of biological quality in the study area is obvious.Phytoplankton is dominated by diatoms,and zooplankton is dominated by copepods.During the project period,the species and biomass of plankton increased.From the perspective of dominant species,the impact of wind power projects on dominant species of phytoplankton is higher than that of zooplankton.The evaluation results showed that the phytoplankton diversity was medium-high level,medium-low level and medium-low level from the establishment to the operation period.The richness is low level,medium low level and medium low level respectively.The evenness is medium level,low level and medium-low level respectively.From the pre-station to the operation period,the diversity of zooplankton was medium-low level,the richness was low level,and the evenness was medium-high level,low level and medium-low level,respectively.(4)By constructing a comprehensive evaluation model for comprehensive analysis,the results show that from the pre-construction period to the operation period,the average comprehensive evaluation indexes of the study area are 0.519,0.475 and 0.558,respectively,and the environmental evaluation grades are general,poor and general,respectively.In addition,through Kriging interpolation and area statistics,it is found that from the pre-station to the project period,the grade I and II areas with excellent environmental grades decreased by18.97 %,while the grade IV and V areas with pollution increased by 32.47 %.From the construction of the station to the operation period,the grade I and II areas with excellent environmental grade increased by 18.42 %,while the grade IV and V areas with pollution decreased by 32.26 %.In summary,the adverse effects of wind power projects on the marine ecological environment mainly occur during the project period,and these adverse effects will gradually weaken or disappear after the construction.However,the obvious fragmentation of marine habitats during the operation period also highlights the importance of marine habitat fragmentation research.