To grasp the characteristics of Pb, Cd, Cu and Zn in mulberry garden soil in Longchuan County, Yunnan Province, the single-factor pollution index method and multi-factor pollution index method were used to analyze the...To grasp the characteristics of Pb, Cd, Cu and Zn in mulberry garden soil in Longchuan County, Yunnan Province, the single-factor pollution index method and multi-factor pollution index method were used to analyze the environmental quality of mulberry garden soil. The results showed that the Zn content in mulberry soils did not exceed normal water based on the soil pollution risk control standards for agricultural land, but the Cd content was high. The single factor pollution index of Pb and Cu did not exceed 2, and the exceedance rate of points was 16% and 24% respectively, while the single factor pollution index of Cd exceeded 3. The pollution of heavy metal Cd existed in the soil of mulberry garden. The average Pi values of soil heavy metals were ranked as Cd > Cu > Zn > Pb. Heavy metal combined pollution index of 6.58, pollution level of heavy pollution. Principal component analysis (PCA) of the four heavy metals showed that the two elements, Pb and Cu, were strongly correlated in their spatial distribution. Longchuan County mulberry soil heavy metal environmental quality evaluation, for the safe use of soil to provide a scientific reference basis.展开更多
The Longchuan River basin lies within the China Sichuan-Yunnan rhomboid block.The NS-trending Yuanmou-Lvzhi River Fault(YLF),NW-trending Chuxiong-Nanhua Fault(CNF)and Shiyang-Huoshaotun Fault(HSF)are found within the ...The Longchuan River basin lies within the China Sichuan-Yunnan rhomboid block.The NS-trending Yuanmou-Lvzhi River Fault(YLF),NW-trending Chuxiong-Nanhua Fault(CNF)and Shiyang-Huoshaotun Fault(HSF)are found within the basin.The nature of the faults is complex,and the tectonic activity distribution characteristics require further clarification.By extraction from a digital elevation model,the measured longitudinal profile and the geomorphic indices of the Longchuan River,basin showed a stream-length gradient index(SL)of 49–650,hypsometric integral(HI)of 0.27–0.58,drainage basin asymmetry factor(AF)of 3.29–27.47,basin shape index(BS)of 0.87–2.75,valley floor width-to-height ratio(VF)of 0.06–5.40,and evaluation of relative tectonic activity(Iat)of 1.6–2.6.Results showed that river morphology and geomorphological indices in the Longchuan River basin were influenced by tectonic activity,bedrock lithology,climatic conditions,and development time,with tectonic activity playing a dominant role.The relative tectonic activity of the Longchuan River basin was zoned,with a gradual increase in relative tectonic activity from the south to the north.That the slip fault zone primarily controls the tectonic deformation of the Longchuan River basin in central Yunnan and the dynamics of the central Yunnan massif are consistent with the“rigid block lateral extrusion”1model.展开更多
文摘To grasp the characteristics of Pb, Cd, Cu and Zn in mulberry garden soil in Longchuan County, Yunnan Province, the single-factor pollution index method and multi-factor pollution index method were used to analyze the environmental quality of mulberry garden soil. The results showed that the Zn content in mulberry soils did not exceed normal water based on the soil pollution risk control standards for agricultural land, but the Cd content was high. The single factor pollution index of Pb and Cu did not exceed 2, and the exceedance rate of points was 16% and 24% respectively, while the single factor pollution index of Cd exceeded 3. The pollution of heavy metal Cd existed in the soil of mulberry garden. The average Pi values of soil heavy metals were ranked as Cd > Cu > Zn > Pb. Heavy metal combined pollution index of 6.58, pollution level of heavy pollution. Principal component analysis (PCA) of the four heavy metals showed that the two elements, Pb and Cu, were strongly correlated in their spatial distribution. Longchuan County mulberry soil heavy metal environmental quality evaluation, for the safe use of soil to provide a scientific reference basis.
基金central Yunnan Province(1:50,000)Chuxiong City,central Yunnan Province(Grant/Award Numbers:DD20220987)the National Natural Science Foundation of China(Grant/Award Numbers:41972118).
文摘The Longchuan River basin lies within the China Sichuan-Yunnan rhomboid block.The NS-trending Yuanmou-Lvzhi River Fault(YLF),NW-trending Chuxiong-Nanhua Fault(CNF)and Shiyang-Huoshaotun Fault(HSF)are found within the basin.The nature of the faults is complex,and the tectonic activity distribution characteristics require further clarification.By extraction from a digital elevation model,the measured longitudinal profile and the geomorphic indices of the Longchuan River,basin showed a stream-length gradient index(SL)of 49–650,hypsometric integral(HI)of 0.27–0.58,drainage basin asymmetry factor(AF)of 3.29–27.47,basin shape index(BS)of 0.87–2.75,valley floor width-to-height ratio(VF)of 0.06–5.40,and evaluation of relative tectonic activity(Iat)of 1.6–2.6.Results showed that river morphology and geomorphological indices in the Longchuan River basin were influenced by tectonic activity,bedrock lithology,climatic conditions,and development time,with tectonic activity playing a dominant role.The relative tectonic activity of the Longchuan River basin was zoned,with a gradual increase in relative tectonic activity from the south to the north.That the slip fault zone primarily controls the tectonic deformation of the Longchuan River basin in central Yunnan and the dynamics of the central Yunnan massif are consistent with the“rigid block lateral extrusion”1model.
