东北农牧交错带啮齿动物群落结构组成及影响因素初探

啮齿动物（Rodentia）是农牧交错区的主要有害动物类群之一，能传播多种疾病，严重威胁当地农牧业发展和人民群众健康。为探究环境因子与啮齿动物群落结构组成的关系，分别于2020年和2021年7—8月，在东北农牧交错带利用铗夜法调查草地、草地—农田交错区和农田3种生境类型中啮齿动物的种类和数量，室内测定调查点土壤和啮齿动物肾脏内的重金属含量。结果表明：捕获的717只啮齿动物包含10个种，优势种为黑线姬鼠（Apodemus agrarius），占捕获总个体数的44.35%；草地生境中啮齿动物的捕获率（14.88%）和群落多样性指数最高。冗余分析（RDA）结果表明，海拔、植被指数影响啮齿动物群落的优势度指数与丰富度指数；黑线仓鼠（Cricetulus barabensis）和黑线姬鼠的铗捕率以及啮齿动物的物种数和均匀度均受土壤重金属污染的影响。黑线仓鼠肾脏器官内重金属富集水平与土壤中重金属浓度呈显著正相关，随着土壤重金属污染的增加，黑线仓鼠的种群密度降低

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^