Category

Climate change

Jun 24
2

Australian alpine plants face bleak future from rapid climate change

By | Climate change, News, Plant Science

Some native plants do not appear to be adapting to warming conditions.

Native Australian alpine plants may not be able to adapt or migrate quickly enough to survive rapid changes in climate change, a UNSW study has found.

The study of 21 plants from Kosciuszko National Park, published in Ecology and Evolution, found that 20 were not responding to warming conditions.

Only one species – the Star Plantain (Plantago muelleri) – showed that it was adapting to warmer conditions by displaying an increase in plant size.

The second plant that showed evidence of a change in plant traits was the Cascade Everlasting (Ozothamnus secundiflorus), but it decreased in leaf thickness over a 125-year time period.

“We predicted leaves would become more thicker, as this would be advantageous if plants were facing longer growing seasons and increasing temperatures,” lead author Meena Sritharan said.

  • Alpine rice flower. Photo: Casey Gibson
  • PhD research scholar Meena Sritharan.
  • Star Plantain. Photo: Casey Gibson.

“Our findings suggest that native alpine plants may not be adapting to the substantial local climate change occurring in Australian alpine regions.

“Australian native alpine plants face a bleak future in the face of rapid climate change.”

Ms Sritharan is a PhD research scholar at ANU who participated in the study as an honours student in the Evolution & Ecology Research Centre at UNSW Science’s School of Biological, Earth and Environmental Sciences.

The point of the study was to gauge whether alpine plants in the southern hemisphere had changed in morphology, or their physical form, over time in response to recent climate warming.

Ms Sritharan said the 21 alpine plants exist in one of the ecosystems known to be least resistant to the effects of climate change.

“Alpine environments are facing higher-than-average increases in temperature in the last century,” Ms Sritharan said.

“But rapid changes in the environment can promote rapid changes in species.”

“Consequently, we expected that a rapid increase in temperature would result in a change in the plant traits we measured, such as size and leaf shape. These changes in plant traits would suggest that alpine plants may be changing in response to a changing climate.”

Previous studies have also shown that both native and invasive plants are capable of rapid changes in their morphology.

The researchers used herbarium (preserved) plant specimens collected between 1890 and 2016, and modern specimens collected in February, 2017.

Examples of the alpine plants they studied included Cushion Caraway (Oreomyrrhis pulvinifica), Alpine Rice flower (Pimelea alpine), Carpet Heath (Pentrachondra pumila) and Snow Aciphyll (Aciphylla glacialis).

The researchers measured five different plant traits: plant size, leaf shape, leaf area, leaf width and specific leaf area (the ratio of the leaf area to leaf dry mass).

Ms Sritharan said the study findings are surprising as the results were contrary to what they expected and what species in the northern hemisphere are facing.

She said plants in the northern hemisphere are changing substantially and adapting to changed environmental conditions brought by climate change.

“For instance, some British plant species (such as White Nettle (Lamium album) and Kenilworth ivy (Cymbalaria muralis) are flowering earlier than expected in the past decade compared to the previous four decades,” Ms Sritharan said.

“The plant height of species growing in tundra ecosystems (treeless regions in cold climates) have also increased with warming over the past three decades.”

Scientists also forecast that plant species will migrate to higher elevations to escape the effects of climate warming.

But Ms Sritharan said she was surprised to find that a shrub – Cascade Everlasting (Ozothamnus secundiflorus) – had moved downslope over time rather than to a higher elevation.

“This indicates that we should look into if, and where, other native Australian alpine species may be migrating to, in the face of climate change,” she said.

Ms Sritharan’s supervisor, the director of UNSW’s Evolution & Ecology Research Centre, Professor Angela Moles, is currently investigating whether Australian alpine plants are shifting their distributions uphill.

“This summer we will be doing heatwave experiments to measure how Australian alpine plants respond to an increased duration of heatwaves, which is what climate researchers forecast for the future,” Prof. Moles said.

Read the paper: Ecology and Evolution

Article source: University of New South Wales

Author: Diane Nazaroff

Image credit: allylester / Pixabay 

Jun 16
1

Global food security: Climate change adaptation requires new cultivars

By | Agriculture, Climate change, News

Climate change induced yield reductions can be compensated by cultivar adaptation and global production can even be increased.

Global agriculture both is one of the major drivers of climate change and strongly affected by it. Rising temperatures are among the main reasons for yield reductions. Therefore, the agricultural sector is faced with the major challenge of adapting to climate change in order to ensure food security in the future. According to a new study carried out by international researchers, the use of locally adapted cultivars can significantly contribute to achieve this goal. The study was led by LMU geographer Dr. Florian Zabel.

For four different climate scenarios, he and his colleagues simulated the impacts of climate change on the global production of maize, rice, soy and wheat and investigated how locally adapted cultivars would affect crop yields. Thereby, the scenarios represent different socio-economic pathways that result in temperature increases ranging between 1.4 and 3.9°C in global average.

Our results show that, at least under moderate warming, we could even increase global yields by almost 20% until the end of the century.

Florian Zabel

“Our results show that, at least under moderate warming, we could generally adapt well to climate change and even increase global yields by almost 20% until the end of the century. Thereby, the increase of atmospheric CO2 partly attributes to the yield increase for some crops, due to positive effects on the efficiency of photosynthesis.” says Zabel.

Strong warming threatens adaptation

If global warming can be restricted to below 1.5°C, as specified in the Paris Agreements, the simulations suggest that 85% of the global cropland area can be optimally cultivated with already available cultivars.

The stronger the warming, the more new cultivars will be needed and the higher the risk that a required locally adapted cultivars that can cope with the changed local conditions will not be available.

In the worst-case scenario, almost 40% of global cropland could require new cultivars.

Florian Zabel

“In the worst-case scenario, almost 40% of global cropland could require new cultivars, of which some would need to have traits that currently do not exist,” says Zabel. Thereby, a critical point is that this even affects globally important production regions, such as North America’s Corn Belt, the world’s most important region for maize production.

“In addition, there are some regions where cultivar adaptation will not be possible, for instance due to a change in future precipitation and possible droughts,” says Zabel. The simulations consider local and regional effects of climate change, and therefore allow identifying regions where locally adapted cultivars could be particularly beneficial for yields. These include large areas of Europe, China and Russia. However, in other parts of the world – including Turkey, Northeastern Brazil, Texas, Kenya and parts of India – adapted cultivars are predicted to have little or no effect on yields, due to a reduction of available water for crops.

Innovative and more efficient breeding methods offer a possible solution. “Conventional breeding approaches often take years,” Zabel points out. “New methods such as CRISPR-Cas could help to develop required cultivars that are specifically adapted to local conditions more quickly and in a more targeted way,” Zabel adds.

The study appears in the journal Global Change Biology. In addition to the authors based at LMU, researchers at the Potsdam Institute for Climate Impact Research, the Technical University of Munich (TUM), the Karlsruhe Institute of Technology, at Columbia University in the City of New York (USA), the University of Chicago (USA), the Université de Liège (Belgium), the International Institute for Applied Systems Analysis (Austria), China Agricultural University in Beijing, the University of Birmingham (UK) and Lund University (Sweden).

Read the paper: Global Change Biology

Article source: Ludwig- Maximilians-Universität München

Image credit: Ludwig- Maximilians-Universität München

Feb 18
1

World’s largest opinion survey on climate change: Majority call for wide-ranging action

By | Climate change, News, Science communication

The results of the Peoples’ Climate Vote, the world’s biggest ever survey of public opinion on climate change are published in January. Covering 50 countries with over half of the world’s population, the survey includes over half a million people under the age of 18, a key constituency on climate change that is typically unable to vote yet in regular elections. 

In high-income countries, belief in the climate emergency was led by the co-hosts of the UN Climate Conference (COP26), UK and Italy (both with 81%), followed by Japan (79%). High-income countries with the lowest numbers of citizens recognizing the climate emergency were the U.S. (65%) and Chile (66%), but these were still solid majorities. Most middle-income countries had high levels of support for the idea of a climate emergency – especially South Africa (76%), the Philippines (74%), Indonesia (69%), Georgia, and Morocco (both 68%). The lowest level of support was found in Moldova: just over 50%.

Detailed results broken down by age, gender, and education level will be shared with governments around the world by the United Nations Development Programme (UNDP), which organized the innovative poll with the University of Oxford. In many participating countries, it is the first time that large-scale polling of public opinion has ever been conducted on the topic of climate change. 2021 is a pivotal year for countries’ climate action commitments, with a key round of negotiations set to take place at the UN Climate Summit in November in Glasgow, UK.

In the survey, respondents were asked if climate change was a global emergency and whether they supported eighteen key climate policies across six action areas: economy, energy, transport, food & farms, nature and protecting people.

Results show that people often want broad climate policies beyond the current state of play. For example, in eight of the ten survey countries with the highest emissions from the power sector, majorities backed more renewable energy. In four out of the five countries with the highest emissions from land-use change and enough data on policy preferences, there was majority support for conserving forests and land. Nine out of ten of the countries with the most urbanized populations backed more use of clean electric cars and buses, or bicycles.

UNDP Administrator Achim Steiner said: “The results of the survey clearly illustrate that urgent climate action has broad support amongst people around the globe, across nationalities, age, gender and education level. But more than that, the poll reveals how people want their policymakers to tackle the crisis. From climate-friendly farming to protecting nature and investing in a green recovery from COVID-19, the survey brings the voice of the people to the forefront of the climate debate. It signals ways in which countries can move forward with public support as we work together to tackle this enormous challenge.”

The innovative survey was distributed across mobile gaming networks in order to include hard-to-reach audiences in traditional polling, like youth under the age of 18. Polling experts at the University of Oxford weighted the huge sample to make it representative of the age, gender, and education population profiles of the countries in the survey, resulting in small margins of error of +/- 2%.

Policies had wide-ranging support, with the most popular being conserving forests and land (54% public support), more solar, wind and renewable power (53%), adopting climate-friendly farming techniques (52%) and investing more in green businesses and jobs (50%).

Prof. Stephen Fisher, Department of Sociology, University of Oxford, said: “The survey – the biggest ever survey of public opinion on climate change – has shown us that mobile gaming networks can not only reach a lot of people, they can engage different kinds of people in a diverse group of countries. The Peoples’ Climate Vote has delivered a treasure trove of data on public opinion that we’ve never seen before. Recognition of the climate emergency is much more widespread than previously thought. We’ve also found that most people clearly want a strong and wide-raging policy response.”

Three climate policies emerged as the most popular of the 18 proposed to respondents: conserve forests and land (54%), use solar, wind and renewable power (53%), and climate-friendly farming techniques (52%). There was only a 24% difference between the most popular and least popular climate policy (promote plant-based diets). The results indicate a broad-based appetite for policy action in response to climate change, but there needs to be more outreach to explain how some of the policies can address it, and how they benefit citizens.

The survey shows a direct link between a person’s level of education and their desire for climate action. There was very high recognition of the climate emergency among those who had attended university or college in all countries, from lower-income countries such as Bhutan (82%) and Democratic Republic of the Congo (82%), to wealthy countries like France (87%) and Japan (82%).

Note:

The percentage of a population estimated to support a particular policy does not indicate that those who did not are against the same policy, since not endorsing a policy could also be due to indifference to it. The country results present what people think who are physically in a particular country. They are not representative of what nationals of a particular country think. So for example, they are representative not of what French people think, but of people in France.

Read the report: United Nations Development Programme

Article source: United Nations Development Programme via Eurekalert

Image credit: UNDP

Feb 10
4

Seeds transfer their microbes to the next generation

By | Climate change, News, Plant Science

Scientists have been pondering if the microbiome of plants is due to nature or nurture. Research at Stockholm University, published in Environmental Microbiology, showed that oak acorns contain a large diversity of microbes, and that oak seedlings inherit their microbiome from these acorns.

“The idea that seeds can be the link between the microbes in the mother tree and its offspring has frequently been discussed, but this is the first time someone proves the transmission route from the seed to the leaves and roots of emerging plants”, says Ahmed Abdelfattah, researcher at the Department of Ecology Environment and Plant Sciences (DEEP) at Stockholm University.

The microorganisms found on the seed are often valuable for the plant, promoting its growth and protecting it against certain diseases. Each plant species harbours a distinct microbial community, with some of the microbes living on its surface and others inside the plant’s tissues.

The finding also means that since the microorganisms from the seed are there first, they can constitute a barrier which influences subsequent colonization by other microbes from the environment. The experiment was done in oaks, since it’s one of the most abundant tree species in the Swedish and European forests.

“The microorganisms from the seed are also expected to be very important for plant health and functioning”, says Ahmed Abdelfattah.

The fossil record indicates that plants have been associated with fungi and bacteria – constituting the microbiome – for more than 400 million years. Several species the scientists found on the oak seeds are already shown by other studies to be involved in the protection against several plant pathogens, growth-promotion, nitrogen-fixing, and the detoxification or biodegradation of toxic environmental pollutants.

Demonstrating inheritance under natural conditions is challenging since seeds are exposed to and dependent on their surrounding environment when they sprout, especially the soil, which is a microbially rich environment. Therefore, it’s nearly impossible to differentiate between which microorganism actually come from the seed or from the soil. The research team therefore used a novel culturing device, to grow oak seedlings in a microbe-free condition and keep the leaves separated from the roots. This allowed them to be certain that the microorganisms came from the seed, and that they could demonstrate that some seed microorganisms migrate to the roots, and some others to the leaves.

“Plant leaves and roots are already known to harbor distinct microbial communities, as shown by several recent studies. In this study however, we were surprised to see that it is also true at an early stage of the plant development, and that the seed could, at least partially, be responsible for these differences”, Says Ahmed Abdelfattah.

“Several breeding companies are taking into consideration the seed microbiome in their programs hoping to have super plants with better genes and better microbes. One technique used, is to treat seeds with beneficial microorganism with the aim that those microbes will eventually colonize the plant and exert their effects throughout the plant’s life”, says Ahmed Abdelfattah.

The next step for the research team is now to discern which is the major source of the of the microbiome – the environment or the seed.

Read the paper: Environmental Microbiology

Article source: Stockholm University

Author: Amanda Gonzalez Bengtsson 

Image credit: Ирина Ирина / Pixabay