Kunwar Ripu M, Khadka Dipak, Thapa-Magar Khum, Adhikari Binaya, Kutal Durga H, Ghimire Rama, Kafle Komal R, Baral Sony, Thapa Gokarna J, Bhandari Ananta
Research Centre for Applied Science and Technology Tribhuvan University Kirtipur Nepal.
South China Agricultural University Guangzhou China.
Ecol Evol. 2025 Mar 30;15(4):e71179. doi: 10.1002/ece3.71179. eCollection 2025 Apr.
By studying the population structure and spatial characteristics, the relationship between tree-ferns and the environment can be reflected, which has high practical significance. In this study, we employed an ensemble distribution model to evaluate the relative contribution of various environmental variables and predict suitable habitats for tree-fern across past, present, and future periods. Fieldwork was carried out between May-June 2019 and September 2022 in 11 districts of Nepal for population sampling and collecting the geocoordinates. Additional geocoordinates were collected from secondary sources such as previous literature, herbarium records, and online resources. We reported the occurrence of tree-ferns from 28 districts within the altitudinal range of 300-2500 m. Longitudinally, the species is distributed only in central and eastern Nepal, with maximum density in central Nepal's Kaski and Lamjung districts. The central mid-hills of Koshi and Gandaki provinces, particularly with the moist habitats and maximum rainfall, are suitable for the distribution of tree-ferns. The projected distribution is influenced mainly by the mean temperature of the coldest quarter-Bio11 (34.9%), precipitation in dry months-Bio14 (34.5%), and mean annual temperature-Bio1 (33.9%). Climate extreme variables (maximum temperature in warmest months-Bio5, minimum temperature in coldest months-Bio6, precipitation in wettest months-Bio13, precipitation in wettest quarter-Bio16) contract the future distribution of species. The result portrays an expansion of suitable habitat for tree-ferns while minor contractions are predicted in four districts of Bagmati province. As the Gandaki province receives the highest rainfall and the Koshi province has rich soil moisture, and precipitation plays a significant role in distribution, humid riverine places of Koshi and Gandaki support tree-fern populations. Tree-ferns could be an indicator species of the moist and humid climate. Given the extensive distribution in Nepal, India, and China, sustainable conservation of tree-ferns through a species conservation action plan holds broader implications.
通过研究种群结构和空间特征，可以反映树蕨与环境之间的关系，这具有很高的实际意义。在本研究中，我们采用了集合分布模型来评估各种环境变量的相对贡献，并预测树蕨在过去、现在和未来时期的适宜栖息地。2019年5月至6月以及2022年9月期间，在尼泊尔的11个地区进行了实地调查，以进行种群采样并收集地理坐标。还从以前的文献、植物标本记录和在线资源等二手来源收集了额外的地理坐标。我们报告了在海拔300 - 2500米范围内28个地区有树蕨出现。从纵向来看，该物种仅分布在尼泊尔中部和东部，在尼泊尔中部的卡斯基和拉姆琼地区密度最大。科希和甘达基省的中部中山地区，特别是有湿润栖息地和最大降雨量的地方，适合树蕨分布。预测的分布主要受最冷月平均温度 - Bio11（34.9%）、干燥月份降水量 - Bio14（34.5%）和年平均温度 - Bio1（33.9%）的影响。气候极端变量（最暖月最高温度 - Bio5、最冷月最低温度 - Bio6、最湿月降水量 - Bio13、最湿季降水量 - Bio16）使该物种未来的分布范围缩小。结果显示树蕨适宜栖息地有所扩大，而预计巴格马蒂省的四个地区会有小幅收缩。由于甘达基省降雨量最高，科希省土壤湿度丰富，且降水在分布中起重要作用，科希和甘达基的湿润河流区域支持树蕨种群生长。树蕨可能是湿润气候的指示物种。鉴于其在尼泊尔、印度和中国的广泛分布，通过物种保护行动计划对树蕨进行可持续保护具有更广泛的意义。
