玛卡种植对云南会泽越冬斑头雁栖息地利用和选择的影响

Effects of Maca Lepidium meyenii planting on habitat utilization and selection of wintering Bar-headed Geese Anser indicus in Huize,Yunnan

玛卡(Lepidium meyenii)作为一种滋补药材在2012年引入我国西南地区,随后种植面积不断扩大,在2018年前后因市场价格回落,其种植规模迅速萎缩。云南会泽黑颈鹤国家级自然保护区念湖片区是斑头雁(Anser indicus)的重要越冬地,也是玛卡的主要产区之一,玛卡种植面积的剧烈变化也为研究农田候鸟对农耕环境的适应性提供了契机。于2015—2020年在使用卫星跟踪技术在会泽保护区对8只越冬斑头雁进行了长时跟踪,在个体水平上比较了玛卡种植期(2015—2018年)和传统作物种植期(2019—2021年)越冬斑头雁栖息地利用和选择的差异,结果表明:(1)在两个时期,斑头雁的栖息地利用模式发生了剧烈改变。在玛卡种植期斑头雁主要利用沼泽(71.29±3.54)%,其次为耕地(18.12±2.90)%和深水水域(10.59±5.97)%,而在传统作物种植期,主要的利用类型则转变为耕地(74.44±4.84)%,其次为沼泽(12.53±6.97)%和深水水域(12.25±2.44)%。(2)对于同一只斑头雁个体,在不同越冬年份,其栖息地利用模式较稳定。A5号斑头雁在2019年和2020年越冬季均表现为对耕地利用率较高,分别为76.95%和80.41%;A6号斑头雁在2019、2020和2021年越冬时,均偏好利用耕地,利用率分别为76.52%、80.61%和75.74%。(3)在栖息地选择方面,斑头雁对9个环境因子均具有选择性。根据随机森林模型评估结果,最重要的因子均为距夜栖地距离,表明斑头雁对夜栖水环境的依赖性。在其它因子上,两个时期则表现出一定的差异性。在玛卡种植期,斑头雁栖息地选择模式中各类因子的优先顺序为夜栖地>主要觅食地>回避类栖息地>人为干扰因子;在传统作物种植期则为夜栖地>回避类栖息地>人为干扰因子>主要觅食地。综合来看,玛卡种植会对斑头雁产生不利影响,不仅会直接减少斑头雁的优质栖息地面积,而且会直接改变斑头雁栖息地利用和选择模式。建议在保护区内或周边区域实施大规模农业耕种模式调整时,应充分考虑农田鸟类的栖息地需求,进行科学管理。

Maca(Lepidium meyenii)was introduced to southwest China as a tonic herb in 2012.Subsequently,the planting area expanded,however its plantation scale shrank rapidly around 2018 due to the price drop.The Nianhu zone of Yunnan′s Huize Black-necked Crane National Nature Reserve is an important wintering ground for the Bar-headed goose(Anser indicus).It is also one of the main production areas for maca.The drastic changes in the maca planting area provide an opportunity to study how migratory farmland birds adapt to changes in the farming environment.From 2015 to 2020,eight wintering Bar-headed geese were tracked in the Huize Nature Reserve over a long period using satellite tracking technology.Their habitat use and selection were compared at the individual level during the maca planting period(2015—2018)and the traditional crop planting period(2019—2021).Our results showed that:(1)The habitat use patterns of Bar-headed geese changed greatly between the two periods.During maca planting,Bar-headed geese mainly used marshes(71.29±3.54)%followed by cultivated land(18.12±2.90)%and deep water(10.59±5.97)%.In traditional crop planting,their main habitat use shifted to cultivated land(74.44±4.84)%,then marshes(12.53±6.97)%and deep water(12.25±2.44)%.(2)For the same Bar-headed goose individual,the habitat use pattern was more stable in different wintering years.In 2019 and 2020,the goose A5 showed a high utilization rate of farmland in winter,which was 76.95%and 80.41%,respectively.In 2019,2020 and 2021,the goose A6 preferred to use farmland and the utilization rates were 76.52%,80.61%and 75.74%,respectively.(3)In terms of habitat selection,the Bar-headed goose demonstrated selectivity for nine environmental factors.The evaluation results of the random forest model showed that the distance from nocturnal habitat was the most important factor.This highlights the Bar-headed goose′s dependence on the nocturnal water environment.Regarding other factors,there were some differences between the two time periods studied..During the maca planting season,the habitat selection priorities of bar-headed geese were:preferred nocturnal habitats,main foraging grounds,avoided habitats,and anthropogenic disturbance factors.In the traditional crop planting season,the priorities were:preferred nocturnal habitats,avoided habitats,anthropogenic disturbance factors,and main foraging grounds.Overall,maca planting negatively impacts Bar-headed geese.It directly reduces the area of high-quality habitats,and changes how geese use and select habitats.When implementing large-scale farming changes in or near reserves,the habitat needs of farmland birds should be fully considered and managed scientifically.