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Alonso A, Boyero L, Solla A, Ferreira V. Dieback and Replacement of Riparian Trees May Impact Stream Ecosystem Functioning. MICROBIAL ECOLOGY 2024; 87:32. [PMID: 38228918 DOI: 10.1007/s00248-024-02343-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 01/03/2024] [Indexed: 01/18/2024]
Abstract
Alders are nitrogen (N)-fixing riparian trees that promote leaf litter decomposition in streams through their high-nutrient leaf litter inputs. While alders are widespread across Europe, their populations are at risk due to infection by the oomycete Phytophthora ×alni, which causes alder dieback. Moreover, alder death opens a space for the establishment of an aggressive N-fixing invasive species, the black locust (Robinia pseudoacacia). Shifts from riparian vegetation containing healthy to infected alder and, eventually, alder loss and replacement with black locust may alter the key process of leaf litter decomposition and associated microbial decomposer assemblages. We examined this question in a microcosm experiment comparing three types of leaf litter mixtures: one representing an original riparian forest composed of healthy alder (Alnus lusitanica), ash (Fraxinus angustifolia), and poplar (Populus nigra); one with the same species composition where alder had been infected by P. ×alni; and one where alder had been replaced with black locust. The experiment lasted six weeks, and every two weeks, microbially driven decomposition, fungal biomass, reproduction, and assemblage structure were measured. Decomposition was highest in mixtures with infected alder and lowest in mixtures with black locust, reflecting differences in leaf nutrient concentrations. Mixtures with alder showed distinct fungal assemblages and higher sporulation rates than mixtures with black locust. Our results indicate that alder loss and its replacement with black locust may alter key stream ecosystem processes and assemblages, with important changes already occurring during alder infection. This highlights the importance of maintaining heathy riparian forests to preserve proper stream ecosystem functioning.
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Affiliation(s)
- Alberto Alonso
- Department of Plant Biology and Ecology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain.
| | - Luz Boyero
- Department of Plant Biology and Ecology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
- Basque Foundation for Science, IKERBASQUE, Bilbao, Spain
| | - Alejandro Solla
- Faculty of Forestry, Institute for Dehesa Research (INDEHESA), Universidad de Extremadura, Avenida Virgen del Puerto 2, 10600, Plasencia, Spain
| | - Verónica Ferreira
- Marine and Environmental Sciences Centre (MARE), Aquatic Research Network (ARNET), Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
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2
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Wang MQ, Wen Z, Ke J, Chesters D, Li Y, Chen JT, Luo A, Shi X, Zhou QS, Liu XJ, Ma K, Bruelheide H, Schuldt A, Zhu CD. Tree communities and functional traits determine herbivore compositional turnover. Oecologia 2023; 203:205-218. [PMID: 37831151 DOI: 10.1007/s00442-023-05463-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 09/26/2023] [Indexed: 10/14/2023]
Abstract
There are many factors known to drive species turnover, although the mechanisms by which these operate are less clear. Based on comprehensive datasets from the largest tree diversity experiment worldwide (BEF-China), we used shared herbivore species (zeta diversity) and multi-site generalized dissimilarity modelling to investigate the patterns and determinants of species turnover of Lepidoptera herbivores among study plots across a gradient in tree species richness. We found that zeta diversity declined sharply with an increasing number of study plots, with complete changes in caterpillar species composition observed even at the fine spatial scale of our study. Plant community characteristics rather than abiotic factors were found to play key roles in driving caterpillar compositional turnover, although these effects varied with an increasing number of study plots considered, due to the varying contributions of rare and common species to compositional turnover. Our study reveals details of the impact of phylogeny- and trait-mediated processes of trees on herbivore compositional turnover, which has implications for forest management and conservation and shows potential avenues for maintenance of heterogeneity in herbivore communities.
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Affiliation(s)
- Ming-Qiang Wang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 4 Renmin South Road, Wuhou District, Chengdu, 610041, China
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
- Forest Nature Conservation, University of Göttingen, Buesgenweg 3, 37077, Göttingen, Germany
| | - Zhixin Wen
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Jinzhao Ke
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 4 Renmin South Road, Wuhou District, Chengdu, 610041, China
- College of Biological Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Douglas Chesters
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Yi Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Jing-Ting Chen
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
- College of Biological Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Arong Luo
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Xiaoyu Shi
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Qing-Song Zhou
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - Xiao-Juan Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Keping Ma
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093, China
- School of Resources and Environmental Sciences, University of Chinese Academy of Sciences, Beijing, 101314, China
| | - Helge Bruelheide
- Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Am Kirchtor 1, 06108, Halle, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Puschstr. 4, 04103, Leipzig, Germany
| | - Andreas Schuldt
- Forest Nature Conservation, University of Göttingen, Buesgenweg 3, 37077, Göttingen, Germany.
| | - Chao-Dong Zhu
- CAS Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.
- College of Biological Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing, 100049, China.
- State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China.
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Rideout NK, Compson ZG, Monk WA, Bruce MR, Hajibabaei M, Porter TM, Wright MTG, Baird DJ. Environmental filtering of macroinvertebrate traits influences ecosystem functioning in a large river floodplain. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Natalie K. Rideout
- Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
| | - Zacchaeus G. Compson
- Environment and Climate Change Canada @ Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
- Department of Biological Sciences, Advanced Environmental Research Institute University of North Texas Denton TX USA
| | - Wendy A. Monk
- Environment and Climate Change Canada @ Canadian Rivers Institute, Faculty of Forestry and Environmental Management University of New Brunswick Fredericton NB Canada
| | - Meghann R. Bruce
- Canadian Rivers Institute @ University of New Brunswick Fredericton NB Canada
| | - Mehrdad Hajibabaei
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Teresita M. Porter
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Michael T. G. Wright
- Centre for Biodiversity Genomics and Department of Integrative Biology University of Guelph ON Canada
| | - Donald J. Baird
- Environment and Climate Change Canada @ Canadian Rivers Institute, Department of Biology University of New Brunswick Fredericton NB Canada
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Growth-defense trade-offs shape population genetic composition in an iconic forest tree species. Proc Natl Acad Sci U S A 2021; 118:2103162118. [PMID: 34507992 DOI: 10.1073/pnas.2103162118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/09/2021] [Indexed: 12/30/2022] Open
Abstract
All organisms experience fundamental conflicts between divergent metabolic processes. In plants, a pivotal conflict occurs between allocation to growth, which accelerates resource acquisition, and to defense, which protects existing tissue against herbivory. Trade-offs between growth and defense traits are not universally observed, and a central prediction of plant evolutionary ecology is that context-dependence of these trade-offs contributes to the maintenance of intraspecific variation in defense [Züst and Agrawal, Annu. Rev. Plant Biol., 68, 513-534 (2017)]. This prediction has rarely been tested, however, and the evolutionary consequences of growth-defense trade-offs in different environments are poorly understood, especially in long-lived species [Cipollini et al., Annual Plant Reviews (Wiley, 2014), pp. 263-307]. Here we show that intraspecific trait trade-offs, even when fixed across divergent environments, interact with competition to drive natural selection of tree genotypes corresponding to their growth-defense phenotypes. Our results show that a functional trait trade-off, when coupled with environmental variation, causes real-time divergence in the genetic architecture of tree populations in an experimental setting. Specifically, competitive selection for faster growth resulted in dominance by fast-growing tree genotypes that were poorly defended against natural enemies. This outcome is a signature example of eco-evolutionary dynamics: Competitive interactions affected microevolutionary trajectories on a timescale relevant to subsequent ecological interactions [Brunner et al., Funct. Ecol. 33, 7-12 (2019)]. Eco-evolutionary drivers of tree growth and defense are thus critical to stand-level trait variation, which structures communities and ecosystems over expansive spatiotemporal scales.
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Jeplawy JR, Cooper HF, Marks J, Lindroth RL, Andrews MI, Compson ZG, Gehring C, Hultine KR, Grady K, Whitham TG, Allan GJ, Best RJ. Plastic responses to hot temperatures homogenize riparian leaf litter, speed decomposition, and reduce detritivores. Ecology 2021; 102:e03461. [PMID: 34236702 DOI: 10.1002/ecy.3461] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/12/2021] [Accepted: 05/13/2021] [Indexed: 01/10/2023]
Abstract
Efforts to maintain the function of critical ecosystems under climate change often begin with foundation species. In the southwestern United States, cottonwood trees support diverse communities in riparian ecosystems that are threatened by rising temperatures. Genetic variation within cottonwoods shapes communities and ecosystems, but these effects may be modified by phenotypic plasticity, where genotype traits change in response to environmental conditions. Here, we investigated plasticity in Fremont cottonwood (Populus fremontii) leaf litter traits as well as the consequences of plasticity for riparian ecosystems. We used three common gardens each planted with genotypes from six genetically divergent populations spanning a 12°C temperature gradient, and a decomposition experiment in a common stream environment. We found that leaf litter area, specific leaf area, and carbon to nitrogen ratio (C:N) were determined by interactions between genetics and growing environment, as was the subsequent rate of litter decomposition. Most of the genetic variation in leaf litter traits appeared among rather than within source populations with distinct climate histories. Source populations from hotter climates generally produced litter that decomposed more quickly, but plasticity varied the magnitude of this effect. We also found that hotter growing conditions reduced the variation in litter traits produced across genotypes, homogenizing the litter inputs to riparian ecosystems. All genotypes in the hottest garden produced comparatively small leaves that decomposed quickly and supported lower abundances of aquatic invertebrates, whereas the same genotypes in the coldest garden produced litter with distinct morphologies and decomposition rates. Our results suggest that plastic responses to climate stress may constrict the expression of genetic variation in predictable ways that impact communities and ecosystems. Understanding these interactions between genetic and environmental variation is critical to our ability to plan for the role of foundation species when managing and restoring riparian ecosystems in a warming world.
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Affiliation(s)
- Joann R Jeplawy
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Tetra Tech, Inc., Denver, Colorado, 80202, USA
| | - Hillary F Cooper
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Jane Marks
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Richard L Lindroth
- Department of Entomology, University of Wisconsin-Madison, Madison, Wisconsin, 53706, USA
| | - Morgan I Andrews
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Zacchaeus G Compson
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, Denton, Texas, 76203, USA
| | - Catherine Gehring
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Kevin R Hultine
- Department of Research, Conservation and Collections, Desert Botanical Garden, Phoenix, Arizona, 85008, USA
| | - Kevin Grady
- Department of Forestry, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Thomas G Whitham
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Gerard J Allan
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, 86011, USA.,Center for Adaptable Western Landscapes, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Rebecca J Best
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA
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7
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The Influence of Leaf Type on Carbon and Nitrogen Assimilation by Aquatic Invertebrate Communities: A New Perspective on Trophic Efficiency. Ecosystems 2020. [DOI: 10.1007/s10021-020-00550-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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8
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Marks JC. Revisiting the Fates of Dead Leaves That Fall into Streams. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019. [DOI: 10.1146/annurev-ecolsys-110218-024755] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As terrestrial leaf litter decomposes in rivers, its constituent elements follow multiple pathways. Carbon leached as dissolved organic matter can be quickly taken up by microbes, then respired before it can be transferred to the macroscopic food web. Alternatively, this detrital carbon can be ingested and assimilated by aquatic invertebrates, so it is retained longer in the stream and transferred to higher trophic levels. Microbial growth on litter can affect invertebrates through three pathways, which are not mutually exclusive. First, microbes can facilitate invertebrate feeding, improving food quality by conditioning leaves and making them more palatable for invertebrates. Second, microbes can be prey for invertebrates. Third, microbes can compete with invertebrates for resources bound within litter and may produce compounds that retard carbon and nitrogen fluxes to invertebrates. As litter is broken down into smaller particles, there are many opportunities for its elements to reenter the stream food web. Here, I describe a conceptual framework for evaluating how traits of leaf litter will affect its fate in food webs and ecosystems that is useful for predicting how global change will alter carbon fluxes into and out of streams.
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Affiliation(s)
- Jane C. Marks
- Department of Biological Sciences and Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona 86011, USA
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Selmants PC, Schweitzer JA, Adair KL, Holeski LM, Lindroth RL, Hart SC, Whitham TG. Genetic variation in tree leaf chemistry predicts the abundance and activity of autotrophic soil microorganisms. Ecosphere 2019. [DOI: 10.1002/ecs2.2795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Paul C. Selmants
- U.S. Geological Survey Western Geographic Science Center Menlo Park California USA
| | - Jennifer A. Schweitzer
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee USA
| | - Karen L. Adair
- Institute of Ecology and Evolution University of Oregon Eugene Oregon USA
| | - Liza M. Holeski
- Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
| | - Richard L. Lindroth
- Department of Entomology University of Wisconsin‐Madison Madison Wisconsin USA
| | - Stephen C. Hart
- Department of Life & Environmental Sciences Sierra Nevada Research Institute University of California Merced California USA
| | - Thomas G. Whitham
- Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
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Reznick DN, Losos J, Travis J. From low to high gear: there has been a paradigm shift in our understanding of evolution. Ecol Lett 2018; 22:233-244. [PMID: 30478871 DOI: 10.1111/ele.13189] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 10/10/2018] [Accepted: 10/25/2018] [Indexed: 01/08/2023]
Abstract
Experimental studies of evolution performed in nature and the associated demonstration of rapid evolution, observable on a time scale of months to years, were an acclaimed novelty in the 1980-1990s. Contemporary evolution is now considered ordinary and is an integrated feature of many areas of research. This shift from extraordinary to ordinary reflects a change in the perception of evolution. It was formerly thought of as a historical process, perceived through the footprints left in the fossil record or living organisms. It is now seen as a contemporary process that acts in real time. Here we review how this shift occurred and its consequences for fields as diverse as wildlife management, conservation biology, and ecosystems ecology. Incorporating contemporary evolution in these fields has caused old questions to be recast, changed the answers, caused new and previously inconceivable questions to be addressed, and inspired the development of new subdisciplines. We argue further that the potential of contemporary evolution has yet to be fulfilled. Incorporating evolutionary dynamics in any research program can provide a better assessment of how and why organisms and communities came to be as they are than is attainable without an explicit treatment of these dynamics.
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Affiliation(s)
- David N Reznick
- Department of Evolution, Ecology and Organismal Biology, University of California, Riverside, CA, 92521
| | - Jonathan Losos
- Department of Biology, Washington University, St. Louis, MO, 63130
| | - Joseph Travis
- Department of Biological Science, Florida State University, Tallahassee, FL, 32306-4340
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Siders AC, Compson ZG, Hungate BA, Dijkstra P, Koch GW, Wymore AS, Grandy AS, Marks JC. Litter identity affects assimilation of carbon and nitrogen by a shredding caddisfly. Ecosphere 2018. [DOI: 10.1002/ecs2.2340] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Adam C. Siders
- Center for Ecosystem Science and Society; Northern Arizona University; Flagstaff Arizona 86001 USA
- Department of Biological Sciences; Northern Arizona University; Flagstaff Arizona 86011 USA
| | - Zacchaeus G. Compson
- Canadian Rivers Institute; Department of Biology; University of New Brunswick; Fredericton NB E3B 5A3 Canada
- Environment and Climate Change Canada at Canadian Rivers Institute; Department of Biology; University of New Brunswick; Fredericton E3B 5A3 Canada
| | - Bruce A. Hungate
- Center for Ecosystem Science and Society; Northern Arizona University; Flagstaff Arizona 86001 USA
- Department of Biological Sciences; Northern Arizona University; Flagstaff Arizona 86011 USA
| | - Paul Dijkstra
- Center for Ecosystem Science and Society; Northern Arizona University; Flagstaff Arizona 86001 USA
- Department of Biological Sciences; Northern Arizona University; Flagstaff Arizona 86011 USA
| | - George W. Koch
- Center for Ecosystem Science and Society; Northern Arizona University; Flagstaff Arizona 86001 USA
- Department of Biological Sciences; Northern Arizona University; Flagstaff Arizona 86011 USA
| | - Adam S. Wymore
- Department of Natural Resources and the Environment; University of New Hampshire; Durham New Hampshire 03824 USA
| | - A. Stuart Grandy
- Department of Natural Resources and the Environment; University of New Hampshire; Durham New Hampshire 03824 USA
| | - Jane C. Marks
- Center for Ecosystem Science and Society; Northern Arizona University; Flagstaff Arizona 86001 USA
- Department of Biological Sciences; Northern Arizona University; Flagstaff Arizona 86011 USA
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