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科学家发现草原和森林节肢动物减少的原因
2019-10-31 16:25

草原和森林节肢动物的减少与地貌水平的驱动因素有关,这一成果由德国慕尼黑工业大学Sebastian Seibold等研究人员取得。相关论文10月30日在线发表于国际学术期刊《自然》。

研究人员分析了超过100万个节肢动物的数据(约2700种),这些数据来自于2008年至2017年在德国3个地区的150个草地和140个森林站点进行的标准化调查。草地和森林的总体伽马多样性随着时间的推移而下降,这表明跨地点和区域的物种流失。在每年采样的草地中,生物量、丰度和物种数量分别下降了67%、78%和34%。营养水平的下降是一致的,并且主要影响稀有物种;其规模与当地土地利用强度无关。然而,埋藏在具有较高农业土地覆盖率的地貌中的站点显示出较强的时间下降。在拥有年度清单的30个林地中,生物量和物种数量(而不是丰度)分别下降了41%和36%。对每三年进行一次采样的所有森林场址的分析都支持了这一点。下降影响了稀有和丰富的物种,并且在营养级别上趋势也不同。

这些研究结果表明,节肢动物的生物量、丰富度和营养级物种数量普遍下降。森林中节肢动物的数量减少表明损失不仅限于开放的栖息地。这些结果也表明,节肢动物衰退的主要驱动因素是在较大的空间尺度上起作用,并且(至少对于草原而言)与地貌规模的农业有关。这意味着政策需要解决地貌规模问题,以减轻土地使用的负面影响。

研究人员介绍,关于节肢动物物种的局部灭绝以及节肢动物生物量大量减少的最新报道表明,土地利用集约化是生物多样性减少的主要驱动因素。然而,据研究人员所知,在跨土地利用强度的梯度上,没有节肢动物发生的多地点时间序列可用来确定因果关系。此外,还不清楚哪些土地利用类型和节肢动物群体受到影响,以及观察到的生物量和多样性下降是否相互关联。

附:英文原文

Title: Arthropod decline in grasslands and forests is associated with landscape-level drivers

Author: Sebastian Seibold, Martin M. Gossner, Nadja K. Simons, Nico Blthgen, Jrg Mller, Didem Ambarl, Christian Ammer, Jrgen Bauhus, Markus Fischer, Jan C. Habel, Karl Eduard Linsenmair, Thomas Nauss, Caterina Penone, Daniel Prati, Peter Schall, Ernst-Detlef Schulze, Juliane Vogt, Stephan Wllauer, Wolfgang W. Weisser

Issue&Volume: 2019-10-30

Abstract: Recent reports of local extinctions of arthropod species1, and of massive declines in arthropod biomass2, point to land-use intensification as a major driver of decreasing biodiversity. However, to our knowledge, there are no multisite time series of arthropod occurrences across gradients of land-use intensity with which to confirm causal relationships. Moreover, it remains unclear which land-use types and arthropod groups are affected, and whether the observed declines in biomass and diversity are linked to one another. Here we analyse data from more than 1 million individual arthropods (about 2,700 species), from standardized inventories taken between 2008 and 2017 at 150 grassland and 140 forest sites in 3 regions of Germany. Overall gamma diversity in grasslands and forests decreased over time, indicating loss of species across sites and regions. In annually sampled grasslands, biomass, abundance and number of species declined by 67%, 78% and 34%, respectively. The decline was consistent across trophic levels and mainly affected rare species; its magnitude was independent of local land-use intensity. However, sites embedded in landscapes with a higher cover of agricultural land showed a stronger temporal decline. In 30 forest sites with annual inventories, biomass and species numberbut not abundancedecreased by 41% and 36%, respectively. This was supported by analyses of all forest sites sampled in three-year intervals. The decline affected rare and abundant species, and trends differed across trophic levels. Our results show that there are widespread declines in arthropod biomass, abundance and the number of species across trophic levels. Arthropod declines in forests demonstrate that loss is not restricted to open habitats. Our results suggest that major drivers of arthropod decline act at larger spatial scales, and are (at least for grasslands) associated with agriculture at the landscape level. This implies that policies need to address the landscape scale to mitigate the negative effects of land-use practices. Analyses of a dataset of arthropod biomass, abundance and diversity in grassland and forest habitats in Germany for the period 20082017 reveal that drivers of arthropod declines act at the landscape level.

DOI: 10.1038/s41586-019-1684-3

Source: https://www.nature.com/articles/s41586-019-1684-3

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:43.07
官方网址:http://www.nature.com/
投稿链接:http://www.nature.com/authors/submit_manuscript.html


本期文章:《自然》:Online/在线发表

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