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Rise of the planet of the grapes: climate change through rosé-tinted glasses?

Posted on by Eleanor Davis

 

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Source: French Country Wines

Chardonnay, Ortega, Pinot Noir…the UK produces over 5 million bottles of wine a year (English Wine Producers, 2015). But given the changes in climate occurring across the globe, this production is said to be on the up.

An increasingly hot topic in the media, the numerous negative consequences of global warming such as extreme weather events and rising sea levels are oftendiscussed. However, the resultant increases in average annual temperature and atmospheric CO2 concentrations have opened a window of opportunity for the UK wine industry. This increased wine production in England and Wales is now touted as the unexpected silver lining to climate change’s storm cloud.

With a predicted temperature increase of 2.2 degrees Celsius in the UK by 2100 (MetOffice, 2011), the success of grape varieties in Britain is a perfect example of the ways in which global environmental change can impact plant function.

Climate is a critical factor in viticulture (the growing of wine grapes) and increased levels of atmospheric CO2 have been shown to increase plant growth (Jakobsen et al. 2016). Bindi et al (2001) found that elevated atmospheric CO2 levels had a significant effect on the grapevine Vitis vinifera total fruit weight, leading to an increase in biomass of up to 45%. This is also the case for many other crop and wild plant species with 79 species reviewed by Jablonski et al (2002) producing more flowers, more seeds and a greater total mass.

This increased growth in response to elevated atmospheric CO2 can be attributed to plants fixing the CO2 through photosynthesis – the process through which plants produce glucose from carbon dioxide and water. Increased abundance of CO2 in the atmosphere leads to increased carbon fixation and hence more growth (Drake et al. 1997). As global warming trends continue, it is expected that many crops will exhibit increased growth rates as CO2 conditions become increasingly favourable.

However, whilst viticulture in the UK are experiencing a boom, vineyards elsewhere are struggling. For example, many grape varieties in Australia are no longer able to grow due to ongoing environmental change (Mozell & Thach, 2014). This is partly because whilst the atmospheric CO2 increase occurring is favourable for many crops, other factors such as temperature increase are not.

Temperature is a major determinant of plant development and can lead to reduced yield in crops by shortening the plants’ development stages (Craufurd &Wheeler, 2009). Increased temperatures can also vastly reduce the land area suitable for the growth of certain crops (Hannah et al, 2013). This reflects the reality of Australian viticulture at present and represents a threat to the future of many other crop species.

Ultimately, “wine grape production provides a good test case for measuring indirect impacts […] because viticulture is sensitive to climate” (Hannah et al, 2013). As such, it is important to continue investigating the impacts of environmental change on plants as it is possible that the success of viticulture in the UK represents the rise before the fall.

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References:

Bindi, M., Fibbi, L. and Miglietta, F., 2001. Free Air CO 2 Enrichment (FACE) of grapevine (Vitis vinifera L.): II. Growth and quality of grape and wine in response to elevated CO 2 concentrations. European Journal of Agronomy, 14(2), pp.145-155.

Craufurd, P.Q. and Wheeler, T.R., 2009. Climate change and the flowering time of annual crops. Journal of Experimental Botany, 60(9), pp.2529-2539.

Drake, B.G., Gonzàlez-Meler, M.A. and Long, S.P., 1997. More efficient plants: a consequence of rising atmospheric CO2?. Annual review of plant biology, 48(1), pp.609-639.

English Wine Producers, 2015. English Wine Industry: Statistics, Facts and Figures. Available online at http://www.englishwineproducers.co.uk/background/stats/ [Accessed 17th March 2017]

Hannah, L., Roehrdanz, P.R., Ikegami, M., Shepard, A.V., Shaw, M.R., Tabor, G., Zhi, L., Marquet, P.A. and Hijmans, R.J., 2013. Climate change, wine, and conservation. Proceedings of the National Academy of Sciences, 110(17), pp.6907-6912.

Jablonski, L.M., Wang, X. and Curtis, P.S., 2002. Plant reproduction under elevated CO2 conditions: a meta‐analysis of reports on 79 crop and wild species. New Phytologist, 156(1), pp.9-26.

Jakobsen, I., Smith, S.E., Smith, F.A., Watts-Williams, S.J., Clausen, S.S. and Grønlund, M., 2016. Plant growth responses to elevated atmospheric CO2 are increased by phosphorus sufficiency but not by arbuscular mycorrhizas. Journal of experimental botany, 67(21), pp.6173-6186.

MetOffice, 2011. Climate: Observations, projections and impacts. United Kingdom [PDF]. Available online at http://www.metoffice.gov.uk/media/pdf/t/r/UK.pdf [Accessed 17th March 2017]

Mozell, M.R. and Thach, L., 2014. The impact of climate change on the global wine industry: Challenges & solutions. Wine Economics and Policy, 3(2), pp.81-89.



Climate change even sets plants up to compete

Posted on by Selina Carlhoff

It is well known that plants photosynthesize and use carbon dioxide to produce energy and oxygen. But did you know that different photosynthetic pathways might have a huge impact on how plants will react to climate change? Continue reading “Climate change even sets plants up to compete” →



A perfect invader for the perfect invasion

Posted on by Aaron Shakides

Elegant yet destructive, subtle yet menacing. The Lionfish colonization of the Caribbean was a perfect invasion. fishnew

Red Lionfish (Pterois volitans) are a beautiful, elegant fish, yet as the saying goes, “never judge a book by its cover”. Lionfish have invaded and colonized most parts of the Caribbean with the species spreading so fast that researchers and marine biologists are worried about the future of the Caribbean ecosystem.

 

What are invasive species?

Invasive species are known to cause extinctions of species and reduction in ecosystem biodiversity as they often outcompete other species in their newly invaded ecosystems². An invasive species is a species not originally from an ecosystem causing economic or environmental harm with potential harm to human health³. Invasive species are often unintended hitchhikers on cargo ships being carried around the world in ballast water and in shipped goods. Over the past few years, lionfish have become the poster child for invasive species in the Atlantic Ocean, receiving as much attention as zebra mussels and Asian carp⁴.

 

Why are lionfish in the Caribbean?

Native to the Pacific and Indian ocean, the red lionfish were first seen in the Caribbean in the late 1980s and now have spread all throughout the Caribbean as seen in the image below. These bewitchingly beautiful fish come armed with highly venomous spines, having very few natural predators, a perfect facilitator for a successful invasion. Lionfish continue to spread through the Caribbean (as seen in figure 2⁵) due to very fortunate characteristics of being very resilient to large temperature variations and biologically resistant to most diseases and parasites⁶.

maps

How are invasive species affecting ecosystems?

Coral reefs are amongst the most diverse ecosystems on earth with all parts of this ecosystem dependent on one another from life cycles of organisms to biological structure and function of organisms. Invasive species often disturb functioning habitats by eating juvenile fish⁹, reducing fish populations and disturbing the balances of reef ecosystems and essentially modifying the ecosystems¹⁰. This is what happened with the lionfish resulting in concern from researchers and marine biologists to the long-term future of the reefs with a change in the ecosystem structure and function.

 

Invasive species often can carry disease with them having massive effects on organisms living in the ecosystem. Organisms living within the ecosystem may be vulnerable to new disease, reducing the organisms chance of survival. An example of this is the Dutch Elm disease being introduced into America and Europe resulting in the rotting of tree roots and starving the tree of nutrition.

 

Why are lionfish damaging?

Lionfish feast upon juvenile fish and small crustaceans around coral reefs, with research identifying that a single lionfish residing on a patch of coral reef can reduce recruitment of juvenile fish by 79%, greatly reducing fish biodiversity⁴ ⁷. The lionfish’s’ prey is essential in reducing toxic algae that poison and suffocate the coral reefs, which without reduce the growth of corals⁴. The expansion of lionfish put additional stress on coral reefs already stressed by climate change, pollution, acidification, disease and overfishing⁸.

 

 

 

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References

 

1 – Clark, C., 2015. Lionfish study explores idea of eating an ecological problem. Available at: https://phys.org/news/2015-11-lionfish-explores-idea-ecological-problem.html. Last accessed on 12th March 2017.

 

2 – Clavero Pineda, M. and García-Berthou, E., 2005. Invasive species are a leading cause of animal extinctions. Trends in Ecology and Evolution.

 

3 – Mooney, H.A. and Hobbs, R.J. eds., 2000. Invasive species in a changing world (Vol. 23). Washington, DC: Island Press.

 

4 – NOAA., 2014. Invasive Lionfish Threaten Coral Reefs and Fisheries. NOAA Fisheries. Available at: http://www.nmfs.noaa.gov/stories/2014/12/12_01_14impacts_of_invasive_lionfish.html. Last accessed on 14th March 2017.

 

5 – USGS., 2017. Nonindigenous Aquatic Species. Available at: https://nas.er.usgs.gov/queries/SpeciesAnimatedMap.aspx?speciesID=963. Last accessed on 20th March 2017.

 

6 – Morris Jr, J.A. and Whitfield, P.E., 2009. Biology, ecology, control and management of the invasive Indo-Pacific lionfish: an updated integrated assessment.

 

7 – Albins, M.A. and Hixon, M.A., 2008. Invasive Indo-Pacific lionfish Pterois volitans reduce recruitment of Atlantic coral-reef fishes. Marine Ecology Progress Series, 367, pp.233-238.

 

8 – Goldberg, J. and Wilkinson, C., 2004. Global threats to coral reefs: coral bleaching, global climate change, disease, predator plagues and invasive species. Status of coral reefs of the world, 2004, pp.67-92.

 

9 – Guy, A., 2016. Facing a Plague of Invasive Lionfish, Caribbean and Gulf Communities Get Creative. Oceana. Available at: http://oceana.org/blog/facing-plague-invasive-lionfish-caribbean-and-gulf-communities-get-creative. Last accessed on 19th March 2017.

 

10 – Green, S.J., Akins, J.L., Maljković, A. and Côté, I.M., 2012. Invasive lionfish drive Atlantic coral reef fish declines. PloS one, 7(3).

 

 

 

 



Shedding light on urbanisation: how will our nocturnal species respond to artificial night lighting?

Posted on by Luke Vassor

Moving to Mars, floating cities and building upwards – all suggested solutions for our exploding human population, and with this population comes all of our infrastructure, including artificial lighting.

BUT while we remain on ground-level and on-land here on Earth, how will the species which exist in the dark respond to the one thing which keeps us moving at night, artificial lighting?

Earth's night lighting, as seen from space (source: NASA)
Earth’s night lighting, as seen from space (source: NASA)

 

Species which are active at night, nocturnal species, have evolved to exist at a time when others, like humans, don’t (until recently). However, since the invention of electric lighting 100 years ago, human beings have slowly transformed the global night time environment. This has not only led to a reduction in visible stars in the night sky, but has also had profound ecological effects on our nocturnal communities (Longcore and Rich, 2004).

The reason light can have such a profound impact lies in its use as a cue for nocturnal activities. All organisms have specific “rhythms” as a result of an internal “body clock” synchronising with daily cycles. This circadian rhythm relies on an internal light-controlled timer (Bradshaw and Holzapfel, 2010). Over 60% invertebrate and 30% vertebrate animals exhibit nocturnal rhythms, using the rising and setting of the sun as their cue to emerge from their day-time roosts or shelters (Hölker et al., 2010). Our human artificial lighting can confuse organisms in determining when it is day or night and interfere with these rhythms (Longcore et al., 2015).

Long-exposure photograph of insects attracted to a municipal street light
Long-exposure photograph of insects attracted to a municipal street light

However, it is actually much more complicated a picture than nocturnal organisms becoming disoriented by artificial lighting. This is due to a “trophic cascade” which is the knock-on effect along the food chain of an event occurring with one organism at one link in the chain. By disrupting the rhythm of one organism, the consequences can carry across the whole community. This is well documented in one of the most charismatic nocturnal animals, bats. In the UK, all bats use echolocation to navigate in the dark (Speakman, 1995). Among UK bats are fast- and slow-fliers, adapted to different environments. As many of the bat insect prey are attracted to street lights, the fast-fliers can fly underneath the lights to feed on the insects (Matthews et al., 2015). However, slow-fliers tend not to be seen doing this as they are not fast enough to escape predators, to whom they are exposed when beneath the light.

A bat foraging under a street light in Thailand (video screenshot)

This means that whilst it may be argued artificial lights have a positive effect on bats by concentrating their food, only fast-flying species can take advantage, passing through this new environmental filter imposed by artificial light. This may result in fast-fliers out-competing slow-fliers (Arlettaz et al., 2000). In this instance, only certain aerial insect species will survive the enhanced predation from fast-flying bats and move through this new “biotic” filter. As more and more artificial lighting continues to be installed, we may witness a change in the composition of certain nocturnal communities triggered by a shift in the functional traits within certain groups.

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References

Arlettaz, R. et al. (2000) Competition for food by expanding pipistrelle bat populations (Pipistrellus pipistrellus)      might contribute to the decline of lesser horseshoe bats (Rhinolophus hipposideros). Biological Conservation. 93(1),  pp. 55–60.

Bradshaw, W.E. and Holzapfel, C.M. (2010) What Season Is It Anyway? Circadian Tracking vs. Photoperiodic  Anticipation in Insects. Journal of Biological Rhythms. 25(3), pp. 155–165.

Hölker, F. et al. (2010) Light pollution as a biodiversity threat. Trends in Ecology and Evolution. 25(12), pp. 681–682.

Longcore, T. and Rich, C. (2004) Ecological light pollution. Frontiers in Ecology and the Environment. 2(4), pp. 191–  198.

Longcore, T. et al. (2015) Tuning the white light spectrum of light emitting diode lamps to reduce attraction of  nocturnal arthropods. Philosophical Transactions of the Royal Society B: Biological Sciences. 370(1667), 20140125

Mathews, F. et al. (2015) Barriers and benefits: implications of artificial night-lighting for the distribution of  common  bats in Britain and Ireland. Philosophical Transactions of the Royal Society B. Biological Sciences 370,  20140124.

Speakman, J.R. (1995) Chiropteran nocturnality. Symposium of the Zoological Society of London 67(67), pp. 187–  201.

 



Help! We’re Sinking: The Drowning Atoll Island Communities

Posted on by Kayra Salih
Figure 1. A typical atoll island, source: http://www.ventanasvoyage.com/images/coral%20atoll.jpg
Figure 1. A typical atoll island, source: http://www.ventanasvoyage.com/images/coral%20atoll.jpg

What is sea level rise (SLR)?

The term is pretty self-explanatory in the sense that sea level is rising globally; it has risen by ~3.1mm yr-1 since the 1990s (Goelzer et al., 2015). This is due to the complex interactions of many drivers under recent climate change (Figure 2). This SLR is having global consequences including the loss of low-lying land, of which atoll islands are of the most vulnerable and threatened (Nicholls et al., 2007).

Figure 2. Diagram illustrating the causes of SLR, source: https://deq.nc.gov/about/divisions/coastal-management/coastal-management-hot-topics/sea-level-rise
Figure 2. Diagram illustrating the causes of SLR, source: https://deq.nc.gov/about/divisions/coastal-management/coastal-management-hot-topics/sea-level-rise

Atoll Island Communities

Atolls are mid-ocean annular reefs surrounding a central lagoon (Figure 1) (Woodroffe, 2008). Atoll islands are notoriously vulnerable to the effects of SLR for three main reasons (see Figure 3 below) (Woodroffe, 2008):

Figure 3. The three main impacts of SLR on atoll islands.
Figure 3. The three main impacts of SLR on atoll islands.

Impacts on Humans

These environmental changes inevitably have impacts on the surrounding ecosystem; affecting the terrestrial, aquatic and marine communities, including human populations. The world is now experiencing a wave of ‘climate change refugees’ (Farbotko & Lazarus, 2012) who have been forced to seek asylum in other countries, for example the islanders of Tuvalu.

Tuvalu is a country in the South Pacific solely consisting of low-lying coral and atoll islands (Figure 4) (Farbotko & Lazrus, 2012). Residents have already been forced to evacuate their homes due to flooding, in addition to saltwater incursion rendering their groundwater drinking source unsuitable (Connell, 2016). Sea level around Tuvalu is currently rising by ~5.1mm yr-1 (Connell, 2016). This is a common tale throughout Earth’s atoll islands, and one which is likely to become more common in the future.

Figure 4. Map of Tuvalu showing its many atoll islands, source: http://www.nanumea.net/Photos%20page/Tuvalu%20Map%20with%20arrow%20and%20ack%20-%20from%20Smithsonian%20(a).jpg
Figure 4. Map of Tuvalu showing its many atoll islands, source: http://www.nanumea.net/Photos%20page/Tuvalu%20Map%20with%20arrow%20and%20ack%20-%20from %20Smithsonian%20(a).jpg

Effects on Marine Organisms

The marine ecosystem surrounding islands is also experiencing adverse and damaging impacts from sea level rise. For example, the health of coral reefs is already being degraded by warming oceans contributing to coral bleaching (Figure 5).

Figure 5. Infographic explaining coral bleaching and its causes, source: http://oceanservice.noaa.gov/facts/coralbleaching-large.jpg
Figure 5. Infographic explaining coral bleaching and its causes, source: http://oceanservice.noaa.gov/facts/coralbleaching-large.jpg

It can be argued that rising sea levels may in fact protect corals from overexposure to sunlight as they are deeper (Woodroffe & Webster, 2014). However, this will mostly mean that corals are too deep to allow their symbiotic algae to survive, which will ultimately lead to coral death (Woodroffe & Webster, 2014).

These impacts lead to wider community impacts on marine organisms; coral-dependent fish will either migrate or die (Andréfouët et al., 2015). The decline in fish stocks will also affect human populations which depend on this resource. Furthermore, the whole community will be affected by changes in food resources and suitable habitat, possibly leading to the collapse of the ecosystem (Andréfouët at al., 2015).

The future…

More areas are predicted to be underwater in the future according to SLR projections (Goelzer et al., 2015). This will not only have an impact on the animal populations dependent on fragile atoll ecosystems; but also on human populations- with an increasing number of environmental asylum seekers. The future will likely see increasing numbers of atoll island communities drowning!

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References

Andréfouët, S., Dutheil, C., Menkes, C.E., Bador, M. & Lengaigne, M. (2015). Mass mortality events in atoll lagoons: environmental control and increased future vulnerability. Global Change Biology. 21:195-205.

Connell, J. (2016). Last days in the Carteret Islands? Climate change, livelihoods and migration on coral atolls. Asia Pacific Viewpoint. 57:3-15.

Farbotko, C. & Lazrus, H. (2012). The first climate refugees? Contesting global narratives of climate change in Tuvalu. Global Environmental Change. 22:382-390.

Goelzer, H., Huybrechts, P., Loutre, M.F. & Fichefet, T. (2015). Future rates of sea-level rise from long-term coupled climate-ice sheet projections. In: EGU General Assembly Conference Abstracts. 17:15590.

Nicholls, R.J., Wong, P.P., Burkett, V.R., Codignotto, J.O., Hay, J.E., McLean, R.F., Ragoonaden, S. & Woodroffe, C.D. (2007). Coastal systems and low-lying areas. In: Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J. & Hanson, C.E. (Eds.). Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press: UK. pp. 315-356.

Woodroffe, C.D. (2008). Reef-island topography and the vulnerability of atolls to sea-level rise. Global and Planetary Change. 62:77-96.

Woodroffe, C.D. & Webster, J.M. (2014). Coral reefs and sea-level change. Marine Geology. 352:248-267.



Climate Change IS happening, and it’s set to starve the planet… (The opposite of FAKE NEWS!)

Posted on by Anonymous

With the large scale funding cuts of the Environmental Protection Agency in the USA, the current rapid rates of climate change and CO2 release show no hope of stopping.

But seeing as though plants breathe using CO2 (through the process of photosynthesis), and use carbon in their growth, surely the increased amounts of CO2 being pumped into our atmosphere is a good thing for plants?  As studies have shown; perhaps not…

Plants require very specific environmental conditions to function efficiently, and any changes in these conditions can be detrimental.  Although it has been shown that increased CO2 initially causes an increase in the rate of photosynthesis and growth of leaves and roots (Taylor et al 1994), generally, in the long-term, the stimulation of photosynthesis is actually suppressed!

This is mainly due to negative effects on the plants function, such as the build-up of excess starch (sugars) in leaves via increased photosynthesis, hindering breathing of CO2 via pores; called the stomata (Makino & Mae 1999), and increased CO2 also causes the stomata to partially close (Singh 2009), resulting in an inability to respire efficiently (Ryan 1991).

The mechanism for respiration in a plant leaf, through the stomata.
The mechanism for gas exchange in a plant leaf, through the stomata.  Source: Understanding Evolution

The failure to respire efficiently can cause the death of many food crops globally that are vital to feeding our populations!

Increased environmental CO2 also results in global warming due to increased reflection of the Sun’s radiation back to the Earth’s surface; and a temperature increase of 2-3⁰C over the next 30-50 years (IPCC 2007) is predicted to cause problems for our crops.  For example, warmer temperatures affect plants mainly when they are developing, and this has been shown to reduce the numbers of our food crop plants by 80%-90% (Hatfield & Prueger 2015), having dire consequences for our food supplies!

The global change in surface temperature from 1901-2012. A worrying trend that is set to worsen... Source: National Snow & Ice Data Center
The global change in surface temperature from 1901-2012. A worrying trend that is set to worsen… Source: National Snow & Ice Data Center

Climate change is also set to increase the frequency of extreme weather events (Rosenzweig et al 2001). With increased storms and flooding drowning plants in some areas, and in other areas increased drought, resulting in a lack of water for plants to function with, which they rely heavily on for processes such as photosynthesis, vital for growth and survival.  The equation for photosynthesis is shown below, in case you have forgotten…

 

The equation for photosynthesis, showing how carbon dioxide and water are transformed into oxygen and sugars through the light energy from the sun hitting the chlorophyll pigments in the plants cells.
The equation for photosynthesis, showing how carbon dioxide and water are transformed into oxygen and sugars through the light energy from the sun interacting with the chlorophyll pigments in the plants cells.

 

With increasing global temperatures, drought affected areas will increase from 15.4% to 44.0% by 2100 (Li et al 2009) – resulting in less land to grow crops, which will be disastrous for our food security, along with the fact that the number of suitable growing days per year for our crops will decrease by 11% by the year 2100 (Mora et al 2015)!

A sunny day on a Californian beach? Not exactly… This is Californian farmland suffering from a severe drought – completely unusable!
A sunny day on a Californian beach? Not exactly… This is Californian farmland suffering from a severe drought – completely unusable! Source:  New York Times

 

With the saying “Feed the World” becoming more and more poignant, our future looks bleak, as we are set to have less food security per person than ever before due to the detrimental effects that climate change will have on plant function. Also, plants not only provide food, but are also at the heart of our medicines and resources! So maybe Donald Trump ought to reconsider his views on climate change before threatening his new healthcare system before it has begun.

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References:

Hatfield, J. and Prueger, J. (2015). Temperature extremes: Effect on plant growth and development. Weather and Climate Extremes, 10, pp.4-10.

IPCC, (2007). Climate Change 2007: Impacts, Adaptation and Vulnerability. New York: Cambridge University Press, p.17.

Li, Y., Ye, W., Wang, M. and Yan, X. (2009). Climate change and drought: a risk assessment of crop-yield impacts. Climate Research, 39, pp.31-46.

Makino, A. and Mae, T. (1999). Photosynthesis and Plant Growth at Elevated Levels of CO2. Plant and Cell Physiology, 40(10), pp.999-1006.

Mora, C., Caldwell, I., Caldwell, J., Fisher, M., Genco, B. and Running, S. (2015). Suitable Days for Plant Growth Disappear under Projected Climate Change: Potential Human and Biotic Vulnerability. PLOS Biology, 13(6), p.e1002167.

Rosenzweig, C., Iglesius, A., Yang, X., Epstein, P. and Chivian, E. (2001). Climate change and extreme weather events – Implications for food production, plant diseases, and pests. Global Change & Human Health, 2(2), pp.90-104.

Ryan, M. (1991). Effects of Climate Change on Plant Respiration. Ecological Applications, 1(2), pp.157-167.

Singh, S. (2009). Climate change and crops. 1st ed. Berlin: Springer, pp.5-6.

Taylor, G., Ranasinghe, S., Bosac, C., Gardner, S.D.L. and Ferris, R. (1994). Elevated CO2 and plant growth: cellular mechanisms and responses of whole plants. Journal of Experimental Botany, 45, pp.1761-1774.



Too Close To Home – The Effect Of Urbanisation on Global Wildlife

Posted on by Alexis Alders
Urban fox
Hobson (2015)

 

With increasing urbanisation of once wild landscapes, nature is forced to live right on our doorstep. With reports of vicious seagulls, giant rats, and foxes attacking babies, how is wildlife coping with living in the city?

 

Cities currently comprise around 3% of land globally (Faeth et al., 2011) and as this increases, more research is focusing on the animals we share our cities with. Urban development causes habitat fragmentation, enables the invasion of non-native species, and changes regional climates, which leads to a loss of wildlife. But what effect does the change in the environment have on the remaining flora and fauna?

 

In Mexico City, the number of bird species has decreased, but the number of birds overall has increased (Ortega-Alvarez and MacGregor-Fors, 2009). This was also found in butterflies in Mexico (Ramirez-Restrepo et al. 2015). Another pattern found in cities is a decrease in the number of species in more developed areas (Faeth et al. 2011). Decreases in the number of species towards the city centre is due to the avoidance of increased pollution, noise and light in these areas (Ortega-Alvarez and MacGregor-Fors, 2009). Artificial lighting affects the behaviour of bats (Hale et al 2015) and many species are sensitive to high human disturbance (Ortega-Alvarez and MacGregor-Fors, 2009). Few species can survive in cities, as they are inhospitable environments. Known as generalists, these species can eat food from more than one source and can survive in several habitats. Food is more available in the form of human rubbish (Ortega-Alvarez and MacGregor-Fors, 2009) which supports a larger abundance of animals. However, this increase in numbers is only seen in generalists, which can make use of this resource.

 

Which species can survive in a city is determined by hierarchical theoretical filters based on the environment (Aronson et al., 2016). A diagram of this can be seen below.

Urban hierarchical filters
Fig. 1 (Aronson et al., 2016, pg. 2954)

 

Generalists are more likely to meet these criteria due to flexibility within their characteristics. The structure of cities greatly impacts the species that live within them (Aronson et al. 2016). Management intensity in gardens is the main factor affecting spider communities, while bird communities are significantly affected by the abundance of woody plants (Sattler et al. 2010). Butterfly communities are structured by distance to city centre, and distance to well-preserved habitat both of which are linked to the overall structure of the city (Ramirez-Restrepo et al. 2015), as shown below:

City structure mosaic
Fig 1. (Nilon, 2011, pg.47)

So cities have massive effects on communities of wildlife. Therefore, is it inevitable that there will be human-wildlife conflicts? Not necessarily – urban wildlife can teach children living in urban environments about the natural world (Faeth et al., 2011). Additionally, increased biodiversity is linked to sustainable development and a reduction in poverty (Nilon, 2011). So although urban wildlife may be viewed as savage scroungers surviving at the fringes of our society, they actually represent a valuable resource.

 

References

Aronson, M.F., Nilon, C.H., Lepczyk, C.A., Parker, T.S., Warren, P.S., Cilliers, S.S., Goddard, M.A., Hahs, A.K., Herzog, C., Katti, M. and La Sorte, F.A., (2016) Hierarchical filters determine community assembly of urban species pools. Ecology, 97(11), pp.2952-2963.

Faeth, S.H., Bang, C. and Saari, S., (2011) Urban biodiversity: patterns and mechanisms. Annals of the New York Academy of Sciences, 1223(1), pp.69-81.

Hobson, S. (2015) How to photograph urban wildlife, available from: http://www.discoverwildlife.com/wildlife-nature-photography/how-photograph-urban-wildlife [accessed: 15/03/17]

Nilon, C.H., (2011) Urban biodiversity and the importance of management and conservation. Landscape and ecological engineering, 7(1), pp.45-52.

Ortega-Álvarez, R. and MacGregor-Fors, I., (2009) Living in the big city: Effects of urban land-use on bird community structure, diversity, and composition. Landscape and Urban Planning, 90(3), pp.189-195.

Ramírez-Restrepo, L., Cultid-Medina, C.A. and MacGregor-Fors, I., (2015) How many butterflies are there in a city of circa half a million people?. Sustainability, 7(7), pp.8587-8597.

Sattler, T., Borcard, D., Arlettaz, R., Bontadina, F., Legendre, P., Obrist, M.K. and Moretti, M., (2010) Spider, bee, and bird communities in cities are shaped by environmental control and high stochasticity. Ecology, 91(11), pp.3343-3353.

 

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Honey, I can’t bee-lieve what I’m seeing!

Posted on by Luke Donovan
Why does it keep getting hotter ... and where has my home gone?!
Why does it keep getting hotter … and where has my home gone?!

Enjoying that tangerine? That glass of cranberry juice this morning? Waking up in those 100% cotton bed sheets? Well, you can thank the bees. They are the major pollinators of plants and crops in ecosystems and are invaluable to us (Brown and Paxton, 2009; Costanza et al., 1997). Unfortunately, bees are declining, mainly through human causes (boo!). Habitat loss, fragmentation, invasive species and climate change are all factors that are harming the bee populations.

Homes under the hammer – no, not the TV show

The human population is set to reach ~9 billion by 2050 (United Nations, 2004), seeing an increase in resources to feed all these mouths. Habitats need to be converted into farmland to provide crops (which ironically will be pollinated by bees!). It is known that human disturbance can negatively impact bee numbers (Winfree et al., 2009). It could also cause populations to inbreed, meaning they are susceptible to nasty diseases causing death (Brown and Paxton, 2009). The more we harm bee habitats, we are causing detriment to their numbers and are also causing a negative effect on our lives – how counterproductive.

More food and less destruction! (pintrest.com)
More food and less destruction!

How did you get here?!

Sometimes you get an unfamiliar, ugly head pop up in a population which is causing harm to the original species that live there – otherwise known as an invasive species. The process is usually:

  • Introduction
  • Colonisation
  • Naturalisation
  • Spread
  • Impact

 

This can be seen in the Africanized honeybee in South America, largely replacing the European honeybee by outcompeting it (Schweiger et al., 2009).

Left: Africanized Honey bee - Right: European Honey Bee
Left: Africanized Honey bee – Right: European Honey Bee.

Nature has no air-conditioning: Get used to the warm!

Despite belief from certain world leaders, climate change is happening. Climate change brings many problems to bee populations, such as a change in the relationship between plants and the bees and an increase in disease and parasites (Le Conte and Navajas, 2008).

In snowy environments, climate change is causing snow to melt earlier, meaning flowers are emerging earlier, causing bees to be out of sync (phenology), thus causing changes in what’s called their ‘functional traits’ which are traits that typically relate to changes in the environment.

Bees must build up sufficient honey stores so that they can survive over the winter periods, however climate change is causing a change in flower development (and pollen production) whereby drought is responsible for the decline in flower numbers (La Conte and Navajas, 2008). This means that the bees cannot build the right amount of honey stores and starve over the winter period.

The future of the bees

There are conservation efforts to try and help bees (woo!) such as (Brown and Paxton, 2009):

  • Minimising habitat loss
  • Making agricultural habitats bee-friendly
  • Training scientists and the public

 

If bees were to go extinct tomorrow, we would have to self-pollinate EVERYTHING, as bees do all this hard work for us, for nothing. If we lose bees, we lose the planet, we must ensure bees do not leave us otherwise the future will look very bleak (with no hint of yellow and black).

Thanks for reading, lets hope we see these guys buzzing around for a long time
Thanks for reading, lets hope we see these guys buzzing around for a long time.

[498 words]

References

Brown, M. and Paxton, R. (2009). The conservation of bees: a global perspective. Apidologie, 40(3), pp.410-416.

Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’Neill, R., Paruelo, J., Raskin, R., Sutton, P. and van den Belt, M. (1997). The value of the world’s ecosystem services and natural capital. Nature, 387, pp.253-260.

Le Conte, Y. and Navajas, M. (2008). Climate change: impact on honey bee populations and diseases. Rev. sci. tech. Of. int. Epiz, 27(2), pp.499-510.

Schweiger, O., Biesmeijer, J., Bommarco, R., Hickler, T., Hulme, P., Klotz, S., Kühn, I., Moora, M., Nielsen, A., Ohlemüller, R., Petanidou, T., Potts, S., Pyšek, P., Stout, J., Sykes, M., Tscheulin, T., Vilà, M., Walther, G., Westphal, C., Winter, M., Zobel, M. and Settele, J. (2010). Multiple stressors on biotic interactions: how climate change and alien species interact to affect pollination. Biological Reviews, 85, pp.777-795.

United Nations (2004) World Population to 2300, New York. [online] http://www.un.org/esa/population/ publications/longrange2/WorldPop2300final.pdf

Winfree, R., Aguilar, R., Vázquez, D., LeBuhn, G. and Aizen, M. (2009). A meta-analysis of bees’ responses to anthropogenic disturbance. Ecology, 90(8), pp.2068-2076.



Do rising temperatures spell the end of our fruit salads?

Posted on by Anonymous

There is nothing I like more than a fresh fruit salad in the summer heat, especially as its bikini season and those sweet, juicy fruits curb my chocolate cravings. But those fruits that we’ve all come to take for granted could become so much harder to get hold of – that or they’ll cost an arm and a leg to buy – because of climate change (Miller-Rushing & Primack, 2008).

The blackberries and strawberries from this enticing fruit salad could become much harder to get hold of due to their battle with global warming
The blackberries and strawberries from this enticing fruit salad could become much harder to get hold of due to their battle with global warming

We associate all our typical summer fruits (strawberries, peaches, raspberries, blackberries – I’d go on but it’s making me hungry) with warm, sunny weather – so how could global warming possibly be bad for them when they love the heat?! Well, all the fruits mentioned above are from the Rosaceae family and, in order to flower and produce that delicious fruit that we all love, they need to be exposed to cold weather (between -3oC & +13oC, depending on the species) for a matter of weeks (Larcher, 2003; Anderson, 2015; Kurokura et al, 2013). This chilling requirement is called vernalisation, which is needed to keep the seeds dormant. During their dormancy period, seeds take up and store energy which they will need when it’s time for them to flower properly. The chilling time keeps them dormant for long enough that they have plenty of energy stored up for flowering (Khan, 1981).

spring
If seeds do not enter dormancy triggered by cold temperatures, they may germinate and flower too early, leaving their vulnerable parts – leaves and flowers – exposed to fatal freezing (Khan, 1981), as well as being out-of-sync with other members of their own species and their important pollinator pals, the bees and butterflies (Bernier et al, 1993). This makes the flowers job of reproducing difficult. (I know it’s not a plant but you get the idea!)

If this period of chilling doesn’t occur, if it is too short or is interrupted by warming, flowering may be late or early and fruits will not grow properly in response to warm spring temperatures, leading to lower quality produce (Prasad-Gotame, 2014; Larcher, 2003; Anderson, 2015) as they haven’t had enough time to gather energy stores.
In the UK, the winter of 2015 was the warmest on record, just ahead of 2014 and predicted to be beaten by the winter of 2016 (Met Office, 2017). Global temperatures are expected to keep rising as a result of global change, as well as unpredictable weather events such as heatwaves, droughts and storms appearing with it. These factors combined lead to uncertainty for fruit farmers, particularly the warmer winters. They need winters to be cold to make sure their seeds flower properly at the end of dormancy when spring or summer arrive.

 

As temperatures are expected to carry on rising over the foreseeable future, it doesn’t bode well for our summer fruit salads. But not to worry! Scientists across the globe are researching ways to breed resistant plants – that is to say, plants which don’t need a chilling time to produce high quality fruit (Anderson, 2015; Randoux et al, 2012; Anderson, 2007; Kurokura et al, 2013).

 

 

Word count: 428

 

 

References

Anderson, J. (2015). Advances in Plant Dormancy. 1st ed. Cham: Springer International Publishing.

Anderson, N. (2007). Flower breeding and genetics. 1st ed. Palo Alto, Calif.: Ebrary.

Bernier, G., Havelange, A., Houssa, C., Petitjean, A. and Lejeune, P. (1993). Physiological Signals that lnduce Flowering. The Plant Cell, 5, pp.1147-1155.

Khan, A. (1977). The Physiology and biochemistry of seed dormancy and germination. 1st ed. Amsterdam: North-Holland Pub. Co.

Kurokura, T., Mimida, N., Battey, N. and Hytonen, T. (2013). The regulation of seasonal flowering in the Rosaceae. Journal of Experimental Botany, 64(14), pp.4131-4141.

Lange, O. (1981). Physiological plant ecology. 4th ed. Berlin [etc.]: Springer.

Met Office. (2017). UK climate. [online] Available at: http://www.metoffice.gov.uk/climate [Accessed 20 Mar. 2017].

Miller-Rushing, A. and Primack, R. (2008). Global warming and flowering times in thoreau’s concord: a community perspective. Ecology, 89(2), pp.332-341.

Prasad Gotame, T. (2014). Understanding the effect s of temperature on raspberry physiology and gene expression profiles. University of Aarhus.

Randoux, M., Jeauffre, J., Thouroude, T., Vasseur, F., Hamama, L., Juchaux, M., Sakr, S. and Foucher, F. (2012). Gibberellins regulate the transcription of the continuous flowering regulator, RoKSN, a rose TFL1 homologue. Journal of Experimental Botany, 63(18), pp.6543-6554.

 

 



Global Warming: It’s Getting Hot In Here

Posted on by Rosie Chubbock

Warmer summer days, heat waves and mild winters- global warming must be a blessing in disguise, right? Wrong. A global temperature increase of only a few degrees could spell disaster for ecosystems and communities across the world.

warming-map-jpg
Temperatures changes across the globe between 1951 and 2005. (Hansen et al, 2006)

Global warming may be a controversial topic, but the bottom line is the planet IS getting warmer: an average of 0.8oC warmer over the past 40 years to be precise (Hansen et al, 2006). But who’s responsible? Unfortunately it seems we’re the culprits, with increasing carbon emissions from human activity blamed for recent temperature rise. Ice melt and sea level rise are both well-known consequences of global warming, but it’s also causing countless other impacts on species around the globe, from changes in migration and distribution to extinction (Hansen et al, 2006).

Polar ecosystems are perhaps the most vulnerable to warming: Arctic sea ice is disappearing at an alarming rate. For seals and walruses this means a loss of breeding and pupping grounds (Stroeve et al, 2008), causing population declines.

sea-ice
Change in Arctic sea ice over time: over 2 million square kilometers of sea ice has been lost in the past 40 years. (Post et al, 2013 & Perovich and Richter-Menge, 2009)

But the bad news doesn’t end there: sea ice is becoming less accessible and more fragmented, resulting in declining abundance and body condition of polar bears as they struggle to hunt seals (Post et al, 2013). The extreme food shortage has caused our beloved polar bear to start showing rather sinister behaviour: polar bear cannibalism is on the rise. The hunters have become the hunted with mothers eating their cubs and males attacking smaller females (Galligan et al, 2016).

Polar bears: iconic and lovable animals or viscous cannibals?
Polar bears: iconic and lovable animals or vicious cannibals? (Galligan et al, 2016)
Accessing sea ice hunting grounds is becoming more and more challenging for polar bears (Dell'Amore, 2014)
Accessing sea ice hunting grounds is becoming more and more challenging for polar bears as Arctic temperatures increase. (Dell’Amore, 2014)

Surprisingly, the most significant impact of decreasing sea ice in the Arctic ecosystem could be declining algae abundance. Despite its small size, ice algae is absolutely fundamental to the Arctic food web and cannot grow without the presence of sea ice (EPA, 2016).

The complex Arctic food web, displaying how a loss of sea ice can eventually have consequences for the largest mammals in the ecosystem (EPA, 2016).
The complex Arctic food web, displaying how a loss of sea ice can lead to a significant decrease in algae, which can eventually have consequences for even the largest mammals in the ecosystem (EPA, 2016).

Global warming impacts are not confined to the poles: numerous communities are experiencing distribution and migration changes. Multiple alpine plant communities have displayed an average upward shift in elevation of 29 meters per decade as they seek cooler temperatures (Lenoir et al, 2008). This consequently affects the distribution of other species within the ecosystem which rely on the plants for food and shelter.

Warming temperatures mean migratory bird communities in the US are returning up to 13 days earlier than a century ago, and numerous butterfly species in California are arriving earlier than previous years (EPA, 2016). Indirectly, changes in migration can impact other species within the ecosystem: e.g., an earlier increase in food availability for species such as birds which prey on these butterflies.

However some communities are not able to cope with warming, resulting in irreversible consequences. Amphibians are particularly vulnerable to warm/dry conditions, and suggestions have been made that abnormally high temperatures in 1987 caused by global warming were to blame for the extinction of the golden toad (Pounds and Crump, 1994). This isn’t a one off event: warm ocean temperatures in 1988 resulted in the disappearance of the orange-spotted filefish from Japanese waters (Dell’Amore, 2014), and extinctions are only expected to increase as temperatures continue to rise.

The Golden Toad: the first species extinction to be blamed on global warming triggered by human activity. The first of many? (Pounds and Crump, 1994 & Extinct Animals, 2016)
The Golden Toad: endemic to Costa Rica, and the first species extinction to be blamed on global warming triggered by human activity. But is it the first of many? (Pounds and Crump, 1994 & Extinct Animals, 2016)

[500 Words]

References

Dell’Amore, C. (2014) 7 Species Hit Hard by Climate Change- Including One That’s Already Extinct. Available at: http://news.nationalgeographic.com/news/2014/03/140331-global-warming-climate-change-ipcc-animals-science-environment/ [Accessed 10 March 2017]

EPA (2016) Climate Impacts on Ecosystems. Available at: https://www.epa.gov/climate-impacts/climate-impacts-ecosystems [Accessed 2 March 2017]

Extinct Animals (2015) Golden Toad. Available at: http://www.extinctanimals.org/golden-toad.htm [Accessed 12 March 2017]

Galligan, J., Smith, O., and Tran, K. (2016) Does Climate Change Pose a Significant Threat to Polar Bears? Available at: https://blogs.umass.edu/natsci397a-eross/does-climate-change-pose-a-significant-threat-to-polar-bears/ [Accessed 9 March 2017]

Hansen, J., Sato, M., Ruedy, R., Lo, K., Lea, D. W. and Medina-Elizade, M. (2006) Global temperature change. Proc natl Acad Sci USA. 103 (39) pp. 14288-14293

Lenoir, J., Gegout, J. C., Marquet, P. A., Ruffray, P., and Brisse, H. (2008) A significant upward shift in plant species optimum elevation during the 20th century. Science. 320 (5884) pp. 1768-1771

Perovich, D. K., and Richter-Menge, J. A. (2009) Loss of sea ice in the Arctic. Annual Review of Marine Science. 1 pp. 417-441

Post, E., Bhatt, U. S., Bitz, C. M., Brodie, J. F., Fulton, T. L., Hebblewhite, M., Kerby, J., Kutz, S. J., Stirling, I., and Walker, D. A. (2013) Ecological consequences of sea-ice decline. Science. 341 (6145) pp. 519-524

Pounds, J. A., and Crump, M. L. (1994) Amphibian declines and climate disturbance: the case of the golden toad and the harlequin frog. Conservation Biology. 8 pp. 72-85

Stroeve, J., Serreze, M., Drobot, S., Gearheard, S., Holland, M., Maslanik, J., Meier, W., and Scambos, T. (2008) Arctic sea ice extent plummets in 2007. Eos. 89 (2) pp. 13-14