Abstract

One basic task of environmental activities under the conditions of rapid climate changes is to determine the degree of species vulnerability to a certain vector of climate changes. Using Maxent 3.4.1 software, this study has modeled the climatic niche of Daurian pika based on 273 points of its contemporary habitat and attempted to determine the pattern of changes in the spatial location of this niche under extreme scenarios of climate development in 2070. It is shown that the best models in terms of statistical validation unsatisfactorily predict the range of the species niche in areas that were not used during the construction of the model and can serve as a climate surrogate at other time periods. A model for the future projection was selected so that it could provide the statistically best projections of the niche range in other areas. The largest contribution to the model construction was made by two variables: annual mean temperature and coefficient of precipitation variation. The constructed model was validated by the direct check of its projections in two ways. (1) A check for the presence of pika in three previously unexplored localities, where the climatic conditions are suitable for the habitation of Daurian pika according to the model, recorded the species only in one locality. It was then found that other abiotic factors in the other two localities proved to be inconsistent with the requirements of the species. (2) A comparison of the projections of the range to the time periods of 140 000–120 000, 21 000, and 6000 years ago with the fossils of the species in the respective periods shows that all currently known localities are within the ranges projected by the model. The expected climate changes do not lead to critical changes in the spread of living conditions for Ochotona dauurica; however, they may lead to noticeable changes in their area pattern, which is particularly pronounced under the RCP 8.5 development scenario (which projects the highest deviation from the existing distribution, a lower suitability of their contemporary habitats, and an increase in their fragmentation).

中文翻译：

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达里安皮卡气候生态位的空间评估

摘要

在快速的气候变化条件下环境活动的一项基本任务是确定物种对某种气候变化媒介的脆弱程度。这项研究使用Maxent 3.4.1软件，根据Daurian皮卡当代栖息地的273个点对气候生态位进行了建模，并试图确定2070年气候发展极端情景下该生态位的空间位置的变化模式。结果表明，就统计验证而言，最好的模型不能令人满意地预测在模型构建过程中未使用的区域中物种生态位的范围，并且可以在其他时间段充当气候替代指标。选择了一个未来预测模型，以便可以提供其他领域利基范围的统计上最好的预测。对模型构建的最大贡献来自两个变量：年平均温度和降水变化系数。通过以两种方式直接检查其投影来验证构造的模型。（1）根据模型检查了三个以前未曾探索过的地区是否存在皮卡，这些地区的气候条件适合于Daurian皮卡的栖息地，只记录了一个地区的物种。然后发现在其他两个地方的其他非生物因素被证明与该物种的要求不一致。（2）将14万至12万，21000和6000年前的时间范围预测与各个时期的化石进行比较，结果表明所有当前已知的地区都在预测范围内由模型。欧丘子; 但是，它们可能会导致其面积格局发生明显变化，这在RCP 8.5开发方案下尤为突出（该方案预测与现有分布的偏差最大，其当代栖息地的适应性较低，并且其破碎程度增加）。