Studies On Gansu Grassland Rodent Pest Division And Accurate Sustainable Control Technology Of Plateau Pika

(1) The grassland rodent faunal composition of Gansu province was composed of sixty-eight species, accounting for 75.6% of total rodent species of the province, thereinto, most species had determinate ecological value and their population densities were below than EIL. There were about 18～26 species whose population densities maintained above EIL regular in many regions, and they were dominant rodent species of different steppes.(2) Used the disciplinarian of grassland distribution, grassland rodent faunal composition, adaption of grassland rodent to different steppes and universality, protracted, ponderance of grassland rodent pest as the fundamental of grassland rodent pest division, followed history development, zoology adaptability and production practice principle, firstly, the grassland rodent pests of Gansu province were compartmentalized five regions according to indicators of grassland rodent faunal composition, zonation biology climate, zonation vegetation and then thirteen subregions according to indicators of preponderant zonation grassland type, representative rodent distribution and dominant rodent species.(3) A sampling survey had been conducted and the result showed that there was a positive correlation between plateau pika population quantity and plants loss and economy loss which were caused by plateau pika, and the correlation coefficient was 0.9765. The linear regression equation between active burrows(X) of plateau pika and plants loss (M) was M = -16.9603 + 0.9180X. The large area control had been carried out in 1330 hm2 scope and unit area control cost was 25.05 yuan/hm2. Based on calculation, the EIL of plateau pika of alpine meadow and steppe was 130 active burrows per hectare in Dacha township, Sunan country in April, 2008, and the corresponding ratio of economic allowed loss was 7.5%. The theoretical control indexs were put forward on different economic allowed loss rates.(4) The results of orthogonal test L₉(3⁴) for rodenticide, rodenticide concentration, bait collecting volume and bait species showed as follows:â‘ The first three factors had extremely significantly difference, and different factors had different primary-secondary effects to the eliminating mousehole rate, showed as rodenticideï¹¥rodenticide concentrationï¹¥bait collecting volumeï¹¥bait species.â‘¡Because of the different degree significantly between different levels, the eliminating mousehole rate was also influenced with different degree. Thereinto, the average eliminating mousehole rate of Botulin type D was 82.6%, the Botulin type C was 75.0%, the Null was 68.9%. The average eliminating mousehole rate of three rodenticide concentrations between 69.0 and 82.4%. That of three bait collecting volumes were 69.4%, 80.8% and 76.2%, respectively. And that of three baits were 75.3%, 72.7% and 78.4%, respectively.â‘¢The optimal combination was A₂B₃C₂D₃, namely, with 0.15% Botulin type D, used wheat as bait, threw 25 grain poison baits every active burrow would have the best control efficiency.(5) The results of orthogonal test L₉(3⁴) for concentration, bait collecting volume and bait species of Talon showed as follows:â‘ There was no significant difference between test replication, factors and levels of different factors. The average eliminating mousehole rates of all treatment combinations also had little difference, between 81.6% and 86.8%.â‘¡The R value and schematic diagram of relationship between control effect and different factors on different levels showed that the optimal combination was A2B1C1, namely, with 0.01% Talon, used highland barley as bait, threw 5 grams poison bait every active burrow would have the best control efficiency. This combination had not appeared in the nine experimental combinations, but it should be better than A₁B₁C₁ which was the best combination of nine.(6) The results of orthogonal test L₉(3⁴) for concentration, bait collecting volume and bait species of Bromadiolone showed as follows:â‘ There was different degree significant difference between test replication, factors and levels of different factors, therefore, the eliminating mousehole rate was also dissimilar. The eliminating mousehole rate of three rodenticide concentrations (0.005%, 0.010%, 0.015%) were 72.6%, 85.3% and 80.4%, respectively. That of three bait amounts(1g, 2g,3g) were 80.6%, 75.7% and 82.1%, respectively. And that of three baits (highland barley, oat, wheat) were 76.7%, 80.6% and 81.3%, respectively. â‘¡The optimal combination was A₂B₃C₃, namely, with 0.01% Bromadiolone, used wheat as bait, threw 3 grams poison bait every active burrow would have the best control efficiency.