Based on the land use data in Suzhou in 2010,2015 and 2020,combined with socio-economic factors,PLUS model was used to predict the changes of land use types in Suzhou in 2025 and 2030,and InVEST model was used to calculate the habitat quality in Suzhou in 2015,2020,2025 and 2030,respectively.The re-sults showed that compared with 2020,the water area in Suzhou would decrease the most in 2030,from 35.96%to 32.87%,while the construction land area would increase the most,from 28.32%to 31.60%.From the per-spective of spatial distribution,the habitat quality was the best in Taihu and Yangtze River,the second in coastal areas,and relatively poor in urban center areas.From the perspective of time distribution,compared with 2015,the overall habitat quality index in 2030 would decrease from 0.560 to 0.528,showing a downward trend.
A reagent formula and reaction module were designed,and total residual chlorine in water was determined by acid cleaning partition continuous flow analysis.By optimizing the test conditions,the method had good linearity in the range of 0 mg/L to 2.00 mg/L,with the correlation coefficient>0.999.The method detec-tion limit was 0.014 mg/L.The RSD of actual wastewater samples measured 6 times were from 2.2%to 7.3%,and the recoveries were from 96.8%to 106%.Using this method and the national standard method to simultane-ously determine actual wastewater samples and standard solution,the relative deviation of the results by the two methods was 1.2%～7.7%.
Taking Tiande Lake in Zhengzhou as the research area,the optimal band combination for retrie-ving total nitrogen concentration was obtained by using the measured total nitrogen data and spectral reflectance data,and a support vector machine regression(SVR)model was established.Particle swarm optimization(PSO)was used to optimize SVR model,and PSO-SVR model was created,and the accuracy and applicability of the model were verified by using Zhuhai-1 hyperspectral(OHS)data.The results showed that the determination coef-ficient(R2)of the PSO-SVR model was 0.923 6,the root mean square error(RMSE)was 0.103 3 mg/L,and the average relative error(MRE)was 3.656%.The R2,RMSE and MRE of SVR model were 0.808 0,0.203 2 mg/L and 6.583%,respectively.The results of PSO-SVR inversion were better than those of SVR model.The optimization of SVR model by particle swarm was helpful to improve the inversion accuracy of total nitrogen concentration in Tiande Lake,that is,it was feasible to invert total nitrogen concentration by combining measured spectral data with satellite image data.
Due to the limitation of current cultural thinking and development level,there was a significantly difference in the effect of rural garbage collection and transportation between developed and underdeveloped areas in China.Taking typical villages in Jiangsu and Guizhou Provinces as examples,this paper discussed the differ-ences in policy standards,implementation status and public participation awareness of rural garbage collection and transportation between developed and underdeveloped areas.The results showed that compared with developed areas,the regulations of rural garbage collection and treatment were not yet clear in underdeveloped areas,the treatment methods were extensive,and public participation awareness was weak.
By remote sensing interpretation and inversion of the pollution area at sewage outfalls into envi-ronmental water bodies,and combining the monitoring data of emissions from pollutant discharging units,a"fac-tory-river"relationship model between pollution discharge,swage outlet diffusion and receiving water pollution was constructed.Taking sewage outfalls into Qiantang River as an example,a regression equation between wastewater discharge and pollution range was established using remote sensing technology.The discharge at sew-age outlets and the pollution of the river were verified and analyzed by examples.The results showed that there was a positive correlation between the monitoring results at the sewage outfalls into rivers and the discharge of pollutants.The"factory-river"relationship model could be used to monitor the discharge of pollutants from pol-lution sources and the environmental quality of surface water.
