The Influence Of Plateau Pika On The Vegetation Community And Soil Physical And Chemical Properties Of Alpine Meadow In Northwest Sichuan And Its Control Effect

Plateau Pika is a small mammal widely distributed in the ecosystem of the Qinghai Tibet Plateau.It is considered to be one of the important driving factors for the changes of the health status of the alpine meadow in the Qinghai Tibet Plateau.However,there are few reports about the interference of plateau pika on the vegetation and soil of the alpine meadow in Northwest Sichuan.In addition,for a long time,the prevention and control of plateau pika in most areas of Northwest Sichuan has been heavily dependent on a single rodenticide,and there is a huge risk of drug resistance and failure of rodenticide.On the one hand,through field investigation on Zoige grassland in the north of Northwest Sichuan,this study was devoted to explore the disturbance of plateau pika on alpine meadow;on the other hand,the palatability and control effect of four different rodenticides were evaluated and screened In order to provide scientific basis for rodent control and ecological restoration of rodent wasteland in Northwest Sichuan.The results show that:1.The disturbance of plateau pika significantly affected the vegetation community characteristics1)The results showed that the disturbance of plateau pika significantly reduced the vegetation coverage,height,species richness index,diversity index,and evenness index of alpine meadows(P<0.05),but had no significant effect on Simpson Index(P>0.05).With the increase of the interference intensity of plateau pikas,the aboveground vegetation coverage and height showed a significant downward trend(P<0.05),The change trend of richness index,Shannon index and evenness index was consistent,which initially increased and then later decreased with increasing the plateau pika disturbance intensity(P<0.05).2)The aboveground biomass of alpine meadow was significantly reduced by plateau pika disturbance,and with the increase of plateau pika disturbance intensity,the aboveground biomass showed a significant downward trend(P<0.05).3)From the analysis of different plant functional groups,it was found that plateau pika interference significantly reduced the diversity index and important value of functional groups of Gramineae and Leguminosae(P <0.05),but significantly increased the diversity index and important value of Weeds functional group(P < 0.05).The disturbance of plateau pika had the greatest impact on Leguminosae and Gramineae functional groups,followed by Leguminosae,and had the least impact on Cyperaceae functional groups,and with the increase of disturbance intensity of plateau pika,the diversity index of gramineous and leguminous functional groups decreased significantly(P < 0.05),while the diversity index of miscellaneous grass functional groups initially increased and then later decreased with increasing the plateau pika disturbance intensity(P < 0.05).2.Plateau pika significantly affects the physical and chemical properties of alpine meadow soil1)Plateau pika density was significantly negatively correlated with vegetation height,coverage,above-ground biomass,soil water content,soil total nitrogen and total phosphorus content(P < 0.05).2)The disturbance of plateau pika significantly reduced the content of total nitrogen and total phosphorus in the surface soil of alpine meadow(P < 0.05),and with the increase of plateau pika disturbance intensity,the content of total nitrogen and total phosphorus in the surface soil showed a significant downward trend(P < 0.05).3.The density of Plateau Pika and soil physical and chemical properties are closely related to the characteristics of plant community1)Plateau pika density was significantly negatively correlated with vegetation height,coverage,and above-ground biomass(P < 0.05),and negatively correlated with soil water content,soil total nitrogen and total phosphorus content.2)Plateau pika density was significantly positively correlated with diversity index(P < 0.05),and soil water content,soil total nitrogen and total phosphorus content were significantly positively correlated with vegetation coverage,height,and aboveground biomass(P < 0.05).4.Palatability and control effects of four types of rodenticide on plateau pika1)The intake rates(from high to low)were ranked as flucoumafen(92.5%)> Dtype kreotoxin(88.91%)>cholecalciferol(80.00%)>diphenoxylate barium sulfate(66.33%).2)After treatment for 5 days,the hole extermination rates(from high to low)were ranked as D-type kreotoxin(82.41%)> flucoumafen(38.53%)>cholecalciferol(53.67%)>diphenoxylate barium sulfate(56.57%).After treatment for 2 months,the hole extermination rates(from high to low)were ranked as flucoumafen(91.31%)>Dtype kreotoxin(85.79%)>cholecalciferol(70.47%)>diphenoxylate barium sulfate(56.57%).Based on comprehensive analysis,the proper density of plateau pikas not only contributes to the increase in the richness and diversity of the alpine meadow plant community,but also increases the soil water content to a certain extent,and it has positive significance in improving soil conditions.When the plateau pika density exceeds a certain limit,the growth of ground vegetation and underground soil conditions gradually deteriorate,accelerating the reverse succession of alpine meadows.In addition,lucoumafen prevailed over other three agents in palatability and control effect on plateau pika population density and are worthier of application and promotion.