Trade-offs between seed dispersal and dormancy in an amphi-basicarpic cold desert annual

Abstract Many studies have been done on the relationship between variation in morphology, dispersal ability and degree of dormancy of heterocarpic species with dimorphic diaspores. However, there are far fewer such studies on species that produce trimorphic diaspores. Our aim was to compare dormancy and germination of achenes from peripheral, intermediate and central positions in the capitulum of the diaspore-trimorphic cold desert annual Asteraceae species Heteracia szovitsii, an important component of plant communities in the cold deserts of NW China. Dormancy breaking/germination responses of the three achene morphs and of seeds isolated from the pericarp were tested in the laboratory using standard procedures, and seedling emergence phenology of the achene morphs was monitored under natural cold desert temperature conditions in an experimental garden with and without supplemental watering. Depth of dormancy of the three achene morphs was peripheral > intermediate > central. Seedlings from the three morphs emerged in spring and in autumn. Cumulative seedling emergence percentage from achenes during 47 months of burial was central > intermediate > peripheral. Central achene morphs emerged over a period of ~12 months after sowing, while intermediate and peripheral achene morphs did so for ~40 and 47 months, respectively. Thus, H. szovitsii exhibits a temporal dispersal strategy. No viable central or intermediate achene morphs were present after 16 and 40 months, respectively, but ~60 % of the non-emerged peripheral achenes morphs were viable after 47 months. Based on our results on diaspore dormancy and those of a previous study of diaspore spatial dispersal of H. szovitsii, we conclude that this species has a high–intermediate–low risk diaspore dispersal/dormancy strategy that likely increases the chances for population persistence over time and space.

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Seed dispersal as a search strategy: dynamic and fragmented landscapes select for multi-scale movement strategies in plants

Movement Ecology ◽

10.1186/s40462-020-00239-1 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Jelle Treep ◽

Monique de Jager ◽

Frederic Bartumeus ◽

Merel B. Soons

Keyword(s):

Seed Dispersal ◽

Plant Species ◽

Suitable Habitat ◽

Dispersal Strategy ◽

Plant Dispersal ◽

Multi Scale ◽

Reference Framework ◽

Trade Offs ◽

Movement Strategies ◽

Wide Range

Abstract Background Plant dispersal is a critical factor driving ecological responses to global changes. Knowledge on the mechanisms of dispersal is rapidly advancing, but selective pressures responsible for the evolution of dispersal strategies remain elusive. Recent advances in animal movement ecology identified general strategies that may optimize efficiency in animal searches for food or habitat. Here we explore the potential for evolution of similar general movement strategies for plants. Methods We propose that seed dispersal in plants can be viewed as a strategic search for suitable habitat, where the probability of finding such locations has been optimized through evolution of appropriate dispersal kernels. Using model simulations, we demonstrate how dispersal strategies can optimize key dispersal trade-offs between finding habitat, avoiding kin competition, and colonizing new patches. These trade-offs depend strongly on the landscape, resulting in a tight link between optimal dispersal strategy and spatiotemporal habitat distribution. Results Our findings reveal that multi-scale seed dispersal strategies that combine a broad range of dispersal scales, including Lévy-like dispersal, are optimal across a wide range of dynamic and patchy landscapes. At the extremes, static and patchy landscapes select for dispersal strategies dominated by short distances, while uniform and highly unpredictable landscapes both select for dispersal strategies dominated by long distances. Conclusions By viewing plant seed dispersal as a strategic search for suitable habitat, we provide a reference framework for the analysis of plant dispersal data. Consideration of the entire dispersal kernel, including distances across the full range of scales, is key. This reference framework helps identify plant species’ dispersal strategies, the evolutionary forces determining these strategies and their ecological consequences, such as a potential mismatch between plant dispersal strategy and altered spatiotemporal habitat dynamics due to land use change. Our perspective opens up directions for future studies, including exploration of composite search behaviour and ‘informed searches’ in plant species with directed dispersal.

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Nutlet dimorphism in individual flowers of two cold desert annual Lappula species (Boraginaceae): implications for escape by offspring in time and space

Plant Ecology ◽

10.1007/s11258-010-9772-3 ◽

2010 ◽

Vol 209 (2) ◽

pp. 361-374 ◽

Cited By ~ 11

Author(s):

W. B. Ma ◽

X. J. Zhao ◽

D. Y. Tan ◽

C. C. Baskin ◽

J. M. Baskin ◽

...

Keyword(s):

Time And Space ◽

Cold Desert ◽

Desert Annual

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Defaunation effects on plant recruitment depend on size matching and size trade-offs in seed-dispersal networks

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.2664 ◽

2017 ◽

Vol 284 (1855) ◽

pp. 20162664 ◽

Cited By ~ 24

Author(s):

Isabel Donoso ◽

Matthias Schleuning ◽

Daniel García ◽

Jochen Fründ

Keyword(s):

Seed Dispersal ◽

Seed Size ◽

Ecosystem Functioning ◽

Seedling Recruitment ◽

Species Abundance ◽

Ecosystem Functions ◽

Integrated Network ◽

Trade Offs ◽

Functional Consequences ◽

Large Animals

Defaunation by humans causes a loss of large animals in many ecosystems globally. Recent work has emphasized the consequences of downsizing in animal communities for ecosystem functioning. However, no study so far has integrated network theory and life-history trade-offs to mechanistically evaluate the functional consequences of defaunation in plant–animal networks. Here, we simulated an avian seed-dispersal network and its derived ecosystem function seedling recruitment to assess the relative importance of different size-related mechanisms. Specifically, we considered size matching (between bird size and seed size) and size trade-offs, which are driven by differences in plant or animal species abundance (negative size–quantity relationship) as well as in recruitment probability and disperser quality (positive size–quality relationship). Defaunation led to impoverished seedling communities in terms of diversity and seed size, but only if models accounted for size matching. In addition, size trade-off in plants, in concert with size matching, provoked rapid decays in seedling abundance in response to defaunation. These results underscore a disproportional importance of large animals for ecosystem functions. Downsizing in ecological networks will have severe consequences for ecosystem functioning, especially in interaction networks that are structured by size matching between plants and animals.

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Effects of germination season on life history traits and on transgenerational plasticity in seed dormancy in a cold desert annual

Scientific Reports ◽

10.1038/srep25076 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 21

Author(s):

Juan J. Lu ◽

Dun Y. Tan ◽

Carol C. Baskin ◽

Jerry M. Baskin

Keyword(s):

Life History ◽

Seed Dormancy ◽

Life History Traits ◽

Cold Desert ◽

Transgenerational Plasticity ◽

Desert Annual

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Seed Dispersal as a Search Strategy: Dynamic and Fragmented Landscapes Select for Multi-scale Movement Strategies in Plants

10.21203/rs.3.rs-112681/v1 ◽

2020 ◽

Author(s):

Jelle Treep ◽

Monique de Jager ◽

Frederic Bartumeus ◽

Merel B. Soons

Keyword(s):

Seed Dispersal ◽

Plant Species ◽

Suitable Habitat ◽

Dispersal Strategy ◽

Plant Dispersal ◽

Multi Scale ◽

Reference Framework ◽

Trade Offs ◽

Movement Strategies ◽

Wide Range

Abstract Background – Plant dispersal is a critical factor driving ecological responses to global changes. Knowledge on the mechanisms of dispersal is rapidly advancing, but selective pressures responsible for the evolution of dispersal strategies remain elusive. Recent advances in animal movement ecology identified general strategies that may optimize efficiency in animal searches for food or habitat. Here we explore the potential for evolution of similar general movement strategies for plants.Methods – We propose that seed dispersal in plants can be viewed as a strategic search for suitable habitat, where the probability of finding such locations has been optimized through evolution of appropriate dispersal kernels. Using model simulations, we demonstrate how dispersal strategies can optimize key dispersal trade-offs between finding habitat, avoiding kin competition, and colonizing new patches. These trade-offs depend strongly on the landscape, resulting in a tight link between optimal dispersal strategy and spatiotemporal habitat distribution.Results – Our findings reveal that multi-scale seed dispersal strategies that combine a broad range of dispersal scales, including Lévy-like dispersal, are optimal across a wide range of dynamic and patchy landscapes. At the extremes, static and patchy landscapes select for dispersal strategies dominated by short distances, while uniform and highly unpredictable landscapes both select for dispersal strategies dominated by long distances.Conclusions – By viewing plant seed dispersal as a strategic search for suitable habitat, we provide a reference framework for the analysis of plant dispersal data. Consideration of the entire dispersal kernel, including distances across the full range of scales, is key. This reference framework helps identify plant species’ dispersal strategies, the evolutionary forces determining these strategies and their ecological consequences, such as a potential mismatch between plant dispersal strategy and altered spatiotemporal habitat dynamics due to land use change. Our perspective opens up directions for future studies, including exploration of composite search behaviour and ‘informed searches’ in plant species with directed dispersal.

Download Full-text