气候变化领域集成服务门户(CCPortal): Trout and invertebrate assemblages in stream pools through wildfire and drought

CCPortal

DOI	10.1111/fwb.14212
	Trout and invertebrate assemblages in stream pools through wildfire and drought
	Cooper, Scott D.; Wiseman, Sheila W.; DiFiore, Bartholomew P.; Klose, Kristie
发表日期	2024
ISSN	0046-5070
EISSN	1365-2427
起始页码	69
结束页码	2
卷号	69 期号:2
英文摘要	Climate change is increasing the frequency, severity, and extent of wildfires and drought in many parts of the world, with numerous repercussions for the physical, chemical, and biological characteristics of streams. However, information on how these perturbations affect top predators and their impacts on lower trophic levels in streams is limited.The top aquatic predator in southern California streams is native Oncorhynchus mykiss, the endangered southern California steelhead trout (trout). To examine relationships among the distribution of trout, environmental factors, and stream invertebrate resources and assemblages, we sampled pools in 25 stream reaches that differed in the presence (nine reaches) or absence (16 reaches) of trout over 12 years, including eight reaches where trout were extirpated during the study period by drought or post-fire flood disturbances.Trout were present in deep pools with high water and habitat quality. Invertebrate communities in trout pools were dominated by a variety of medium-sized collector-gatherer and shredder invertebrate taxa with non-seasonal life cycles, whereas tadpoles and large, predatory invertebrates (Odonata, Coleoptera, Hemiptera [OCH]), often with atmospheric breather traits, were more abundant in troutless than trout pools.Structural equation modelling of the algal-based food web indicated a trophic cascade from trout to predatory invertebrates to collector-gatherer taxa and weaker direct negative trout effects on grazers; however, both grazers and collector-gatherers also were positively related to macroalgal biomass. Structural equation modelling also suggested that bottom-up interactions and abiotic factors drove the detritus-based food web, with shredder abundance being positively related to leaf litter (coarse particulate organic matter) levels, which, in turn, were positively related to canopy cover and negatively related to flow. These results emphasise the context dependency of trout effects on prey communities and of the relative importance of top-down versus bottom-up interactions on food webs, contingent on environmental conditions (flow, light, nutrients, disturbances) and the abundances and traits of component taxa.Invertebrate assemblage structure changed from a trout to a troutless configuration within a year or two after trout were lost owing to post-fire scouring flows or drought. Increases in OCH abundance after trout were lost were much more variable after drought than after fire. The reappearance of trout in one stream resulted in quick, severe reductions in OCH abundance.These results indicate that climate-change induced disturbances can result in the extirpation of a top predator, with cascading repercussions for stream communities and food webs. This study also emphasises the importance of preserving or restoring refuge habitats, such as deep, shaded, perennial, cool stream pools with high habitat and water quality, to prevent the extirpation of sensitive species and preserve native biodiversity during a time of climate change.
英文关键词	climate change; predators; trophic interactions
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Marine & Freshwater Biology
WOS类目	Ecology ; Marine & Freshwater Biology
WOS记录号	WOS:001136169400001
来源期刊	FRESHWATER BIOLOGY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/309943
作者单位	University of California System; University of California Santa Barbara; University of California System; University of California Santa Barbara; United States Department of Agriculture (USDA); United States Forest Service
推荐引用方式 GB/T 7714	Cooper, Scott D.,Wiseman, Sheila W.,DiFiore, Bartholomew P.,et al. Trout and invertebrate assemblages in stream pools through wildfire and drought[J],2024,69(2).
APA	Cooper, Scott D.,Wiseman, Sheila W.,DiFiore, Bartholomew P.,&Klose, Kristie.(2024).Trout and invertebrate assemblages in stream pools through wildfire and drought.FRESHWATER BIOLOGY,69(2).
MLA	Cooper, Scott D.,et al."Trout and invertebrate assemblages in stream pools through wildfire and drought".FRESHWATER BIOLOGY 69.2(2024).