Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

The upside-down water collection system of Syntrichia caninervis

Nature Plants volume 2, Article number: 16076 (2016) Cite this article

Subjects

Abstract

Desert plants possess highly evolved water conservation and transport systems, from the root structures that maximize absorption of scarce ground water1–5, to the minimization of leaf surface area6 to enhance water retention. Recent attention has focused on leaf structures that are adapted to collect water and promote nucleation from humid air7–9. Syntrichia caninervis Mitt. (Pottiaceae) is one of the most abundant desert mosses in the world and thrives in an extreme environment with multiple but limited water resources (such as dew, fog, snow and rain), yet the mechanisms for water collection and transport have never been completely revealed. S. caninervis has a unique adaptation: it uses a tiny hair (awn) on the end of each leaf to collect water, in addition to that collected by the leaves themselves. Here we show that the unique multiscale structures of the hair are equipped to collect and transport water in four modes: nucleation of water droplets and films on the leaf hair from humid atmospheres; collection of fog droplets on leaf hairs; collection of splash water from raindrops; and transportation of the acquired water to the leaf itself. Fluid nucleation is accomplished in nanostructures, whereas fog droplets are gathered in areas where a high density of small barbs are present and then quickly transported to the leaf at the base of the hair. Our observations reveal nature's optimization of water collection by coupling relevant multiscale physical plant structures with multiscale sources of water.

Climatic variation has driven the evolution of unique plant structures that provide competitive advantages for survival in hostile environments1–3,13,14. For example, common survival strategies include: the minimization of the leaf surface area to reduce water loss6, hydrophobic leaf surfaces to maximize throughfall to the root system15, leaf structures designed to collect water7–9, energy gradients generated by the conical plant geometry and chemical characteristics of the surfaces to externally transport water droplets to advantageous places on the plant7, and extensive root systems for maximal collection of scarce ground water4,5. However, desert mosses have no true roots or ‘conventional’ water transport systems such as vascular bundles. Instead, rhizoids (root-like structures) anchor the plants to the ground and rely on their above-ground structures for water collection, transportation and storage. The moss species found in arid areas such as S. caninervis have adapted to the scarcity of water by developing other unique structures.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Morphology of S. caninervis and the associated awns.
Figure 2: Nucleation of dew on a moss awn surface.
Figure 3: Fog collection on an awn of S. caninervis.
Figure 4: Multifunctional hierarchical water harvest mechanisms of the moss awn.

References

  1. Nørgaard, T. & Dacke, M. Fog-basking behaviour and water collection efficiency in Namib desert darkling beetles. Front. Zool. 7, 23 (2010).

    Article  Google Scholar 

  2. Nørgaard, T., Ebner, M. & Dacke, M. Animal or plant: which is the better fog water collector? PloS ONE 7, e34603 (2012).

    Article  Google Scholar 

  3. Gutterman, Y. Environmental factors and survival strategies of annual plant species in the Negev Desert, Israel. Plant Species Biol. 15, 113–125 (2000).

    Article  Google Scholar 

  4. Gibbens, R. P. & Lenz, J. M. Root systems of some Chihuahuan Desert plants. J. Arid Environ. 49, 221–263 (2001).

    Article  Google Scholar 

  5. Markle, M. S. Root systems of certain desert plants. Bot. Gaz. 177–205 (1917).

    Article  Google Scholar 

  6. Beadle, N. C. W. Soil phosphate and its role in molding segments of the Australian flora and vegetation, with special reference to xeromorphy and sclerophylly. Ecology 47, 992–1007 (1966).

    Article  Google Scholar 

  7. Ju, J. et al. A multi-structural and multi-functional integrated fog collection system in cactus. Nature Commun. 3, 1247 (2012).

    Article  Google Scholar 

  8. Roth-Nebelsick, A. et al. Leaf surface structures enable the endemic Namib Desert grass Stipagrostis sabulicola to irrigate itself with fog water. J. R. Soc. Interface 9, 1965–1974 (2012).

    Article  CAS  Google Scholar 

  9. Andrews, H., Eccles, E., Schofield, W. & Badyal, J. Three-dimensional hierarchical structures for fog harvesting. Langmuir 27, 3798–3802 (2011).

    Article  CAS  Google Scholar 

  10. Zheng, Y. et al. Morphological adaptations to drought and reproductive strategy of the moss Syntrichia caninervis in the Gurbantunggut Desert, China. Arid Land Res. Manage. 25, 116–127 (2011).

    Article  Google Scholar 

  11. Bowker, M. A., Stark, L. R., McLetchie, D. N. & Mishler, B. D. Sex expression, skewed sex ratios, and microhabitat distribution in the dioecious desert moss Syntrichia caninervis (Pottiaceae). Am. J. Bot. 87, 517–526 (2000).

    Article  CAS  Google Scholar 

  12. Tao, Y. & Zhang, Y. M. Effects of leaf hair points of a desert moss on water retention and dew formation: implications for desiccation tolerance. J. Plant Res. 125, 351–360 (2012).

    Article  Google Scholar 

  13. Proctor, M. C. & Tuba, Z. Poikilohydry and homoihydry: antithesis or spectrum of possibilities? New Phytol. 156, 327–349 (2002).

    Article  Google Scholar 

  14. Proctor, M. in Bryophyte Systematics 479–509 (Academic, 1979).

    Google Scholar 

  15. Holder, C. D. The relationship between leaf hydrophobicity, water droplet retention, and leaf angle of common species in a semi-arid region of the western United States. Agric. Forest Meteorol. 152, 11–16 (2012).

    Article  Google Scholar 

  16. Glime, J. M. Bryophyte Ecology, Vol. 1: Physiological Ecology (Michigan Technological University and the International Association of Bryologists, 2007).

  17. Zheng, Y. et al. Directional water collection on wetted spider silk. Nature 463, 640–643 (2010).

    Article  CAS  Google Scholar 

  18. Martorell, C. & Ezcurra, E. The narrow-leaf syndrome: a functional and evolutionary approach to the form of fog-harvesting rosette plants. Oecologia 151, 561–573 (2007).

    Article  Google Scholar 

  19. Park, K.-C., Chhatre, S. S., Srinivasan, S., Cohen, R. E. & McKinley, G. H. Optimal design of permeable fiber network structures for fog harvesting. Langmuir 29, 13269–13277 (2013).

    Article  CAS  Google Scholar 

  20. Garland, J. Some fog droplet size distributions obtained by an impaction method. Q. J. R. Meteorol. Soc. 97, 483–494 (1971).

    Article  Google Scholar 

  21. Lorenceau, É. & Quéré, D. Drops on a conical wire. J. Fluid Mech. 510, 29–45 (2004).

    Article  Google Scholar 

  22. Li, E. Q. & Thoroddsen, S. T. The fastest drop climbing on a wet conical fibre. Phys. Fluids 25, 052105 (2013).

    Article  Google Scholar 

  23. Tokay, A., Petersen, W. A., Gatlin, P. & Wingo, M. Comparison of raindrop size distribution measurements by collocated disdrometers. J. Atmos. Ocean. Technol. 30, 1672–1690 (2013).

    Article  Google Scholar 

  24. Johansson, E., Bolton, K. & Ahlström, P. Simulations of vapor water clusters at vapor–liquid equilibrium. J. Chem. Phys. 123, 024504 (2005).

    Article  Google Scholar 

  25. Proctor, M. C. et al. Desiccation-tolerance in bryophytes a review. Bryologist 110, 595–621 (2007).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We want to thank M. Standing for providing SEM/ESEM support, L. Allphin-Rapier for providing ideas and discussions, Z. Aanderud and his students for providing samples, A. Downing for proof reading and BYU internal support for Z.P. and the SEM/ESEM experiments. The work of Y.Z., N.W. and Y.T. were funded by the National Basic Research Program of China (2014CB954202).

Author information

Authors and Affiliations

  1. Department of Mechanical Engineering, Brigham Young University, 435 CTB, Provo, 84602, Utah, USA

    Zhao Pan

  2. Department of Chemical Engineering, Brigham Young University, Clyde Building, Room 350, Provo, 84602, Utah, USA

    William G. Pitt

  3. Key Laboratory of Biogeography and Bioresources, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Road, Urumqi, 830011, Xinjiang, People's Republic of China

    Yuanming Zhang, Nan Wu & Ye Tao

  4. Department of Mechanical and Aerospace Engineering, Utah State University, 419J 4130 Old Main Road, Logan, 84322, Utah, USA

    Tadd T. Truscott

Authors
  1. Zhao Pan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. William G. Pitt
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yuanming Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Nan Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ye Tao
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Tadd T. Truscott
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

N.W. and Y.Z. originated the research on S. caninervis and provided anatomical studies, both macro and microscopic. Z.P., T.T.T. and W.G.P. designed the experiments, and Z.P. and T.T.T. performed the experiments and analysed the data. Z.P and W.G.P. proposed the mechanisms of nucleation on the moss awn. W.G.P., Z.P. and T.T.T. wrote the text.

Corresponding author

Correspondence to Tadd T. Truscott.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Section ‘Dew nucleation and fog droplet collection in a groove’, Supplementary References, Supplementary Figs 1–3 and captions for Supplementary Videos 1–5. (PDF 1448 kb)

Supplementary Video

Supplementary Video 1 (MP4 383 kb)

Supplementary Video

Supplementary Video 2 (MP4 480 kb)

Supplementary Video

Supplementary Video 3 (MP4 22053 kb)

Supplementary Video

Supplementary Video 4 (MP4 2722 kb)

Supplementary Video

Supplementary Video 5 (MP4 1309 kb)

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Pan, Z., Pitt, W., Zhang, Y. et al. The upside-down water collection system of Syntrichia caninervis. Nature Plants 2, 16076 (2016). https://doi.org/10.1038/nplants.2016.76

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1038/nplants.2016.76

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing