气候变化对6种荒漠植物分布的潜在影响

分析气候变化对植物分布的影响,对保护生物多样性具有重要意义。利用CART(分类和回归树)模型及A2和B2情景,分析了气候变化对短叶假木贼(Anabasis brevifolia)、裸果木(Gymnocarpos przewalskii)、梭梭(Haloxylon ammoden-dron)、膜果麻黄(Ephedra przewalskii)、驼绒藜(Ceratoides latens)和喀什膜果麻黄(Ephedra przewalskii var.kaschgarica)分布范围及空间格局的影响。结果表明:气候变化下,这些植物目前适宜分布范围减小;从新适宜及总适宜分布范围而言,短叶假木贼和梭梭从1991-2020年到2051-2080年时段增加,之后减小,其它植物从1991-2020年到2081-2100年时段减小;喀什膜果麻黄和驼绒藜适宜分布范围减小并破碎化,其它植物向目前适宜分布的西部、西北部(或青海西南部)、昆仑山、阿尔金山和祁连山区扩展;除驼绒藜和喀什膜果麻黄与年均气温变化具显著相关性外,其它植物分布范围与年均气温和降水量变化的相关性较弱(P0.05),除驼绒藜、喀什膜果麻黄和裸果木目前分布范围与年均气温和降水量变化的回归关系较强外,其它植物分布范围与年均气温和年降水量变化多元线性回归关系较弱。上述研究结果表明,气候变化下,这些植物空间分布格局改变,目前分布范围减少,新适宜及总适宜分布范围近期增加,随着气候变化程度的增强,又逐渐减小。

Potential Effects of Climate Change on the Distribution of Six Desert Plants in China

Understanding the effects of climate change on the distribution of species is crucial for the conservation of biodiversity. The effects of climate change on the distribution patterns of Anabasis brevifolia, Gymnocarpos przewalskii, Haloxylon ammodendron, Ephedra przewalskii, Ceratoides latens and Ephedra przewalskii var. kaschgarica in China were analyzed by using the classification and regression tree (CART) niche model and climate change scenarios of A2 and B2. Climate change in China will decrease the current distribution of these plants greatly. A. brevifolia or H. ammodendron will show a new suitable distribution or total suitable distribution region that will increase from 1991–2020 to 2051–2080, then will decrease from 2051–2080 to 2081–2100, whereas the new suitable distribution or total suitable distribution region of the other plants will decrease from 1991–2020 to 2081–2100. In addition, the current distribution region of E. przewalskii var. kaschgarica or C. latens will be fragmented; the southwest, southeast or south region of the current distribution of the other plants will be reduced; and the new regions will expand towards west or northwest, north, northeast of the current distribution region, towards the southwest region of Qinghai province, Konglun mountains, A ErJin mountain or Qilian mountain. The change in the current distribution, new suitable distribution or total suitable distribution region of the plants is poorly related to the change in annual mean air temperature or precipitation in China, except for the correlation between the distribution region of C. latens or E. przewalskii var. kaschgarica and change in annual mean temperature in China. The linear regression relationship between the change in the distribution region of plants and annual mean temperature or annual mean precipitation in China was poor, except for the relationship between the change in the distribution region of C. latens or E. przewalskii var. kaschgarica or the current distribution region of G. przewalskii and change in annual mean air temperature or annual precipitation in China. Climate change in China will cause a change in spatial distribution pattern of plants and decrease the current distribution region and increase the new suitable distribution region of the plants in the near future. With the increasing extent of climate change, climate change in China will cause a decrease in expanding distribution region or total distribution region.