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Giving local communities in Nepal the opportunity to manage their forests has simultaneously reduced deforestation and poverty in the region, new research has shown.

In the largest study of its kind, an international team of experts led by The University of Manchester has found that community-forest management led to a 37% relative reduction in deforestation and a 4.3% relative reduction in poverty.

This is particularly significant in a low income country, where more than a third of the country’s forests are managed by a quarter of the country’s population.

The findings, published in Nature Sustainability, is the largest study on community-based forest management. It estimates the impacts of more than 18,000 community forest initiatives across Nepal, where community-forest management has actively been promoted for several decades.

Forests are critical to sustainable development: they regulate the world’s climate, sequester carbon from the atmosphere, harbour biodiversity, and contribute to the local livelihoods of millions of people worldwide.

Over the past four decades, governments and international organisations have actively promoted community-based forest initiatives as a way to merge natural resource conservation with human development. Local communities now legally manage approximately 13% of the world’s forests.

But evidence of the impact of community-based forest management has been largely limited to small-scale evaluations, or narrowly focused studies until now.

Lead author Dr Johan Oldekop, The University of Manchester said, “Our study demonstrates that community forest management has achieved a clear win-win for people and the environment across an entire country. Nepal proves that with secure rights to land, local communities can conserve resources and prevent environmental degradation.”

“Our study demonstrates that community forest management has achieved a clear win-win for people and the environment across an entire country. Nepal proves that with secure rights to land, local communities can conserve resources and prevent environmental degradation” Dr Johan Oldekop says.

Reductions in deforestation did not occur at a cost to local wellbeing. The study found that areas with community forest management were 51% more likely to witness simultaneous reductions in deforestation and poverty.

Co-author Professor Mark Whittingham, University of Manchester said, “It’s not easy to balance sustainable management of the environment against the needs, or wants, of mankind. These findings highlight one positive solution.”

The research, authored by an interdisciplinary team of ecologists, economists and political scientists, overcomes previous data limitations by using rigorous techniques to analyse publically available data on forests, people, and institutions. The team combined satellite image-based estimates of deforestation with data from Nepal’s national census of 1.36 million households, and information on more than 18,000 community forests.

Co-author author Professor Arun Agrawal, The University of Michigan said, “Identifying a mechanism – community forestry – that can credibly reduce carbon emissions at the same time as improving wellbeing of the poor is an important step forward in global efforts to combat climate change and protect the vulnerable.”

Mexico, Madagascar, and Tanzania have similar community-forest management programmes, with Indonesia and others developing them.

Co-author Katharine Sims, Amherst College, said, “We sought to learn from Nepal’s experience implementing an innovative conservation policy. We hope our methods will be useful for future study of community forestry in different contexts and compared to alternate governance structures.”

If other areas are able to replicate Nepal’s success, community-forest management could play an even greater role in achieving multiple Sustainable Development Goals.

Read the paper: Nature Sustainability

Article source: University of Manchester

Image: Pixabay

University of Cordoba research analyzes how changes in the structure of soil microbiota affect holm oak decline

Holm oak decline, which threatens dehesa sustainability, has got governments, farmers, civilians and the research community to join forces in protecting this ecosystem. Though the pseudofungus oomycete Phytophthora cinnamomisería is thought to be the main cause of holm oak decline, climate conditions have been shown to influence as well. Even so, this puzzle has yet to be solved.

In search of the last few pieces to help understand how the disease develops, University of Cordoba Forest Engineering researchers Francisco Ruiz and Rafael Mª Navarro, in collaboration with researcher Alejandro Pérez de Luque from IFAPA(Agricultural and Fishing Training Research Institute of Andalusia, Alameda del Obispo center), and international researchers, carried out a study on microorganism biodiversity in soil by means of using molecular techniques, in order to analyze if and how interactions among soil microorganisms influence the seriousness of the disease.

The study focused on fungi and oomycetes that live in soil, and the interactions that occur among them. In addition, it confirms that changes in microbiota structure and biodiversity are fundamental for woodland health in two ways: on the one hand, interactions among soil microorganisms directly influence pathogens that affect holm oak and on the other, the presence of some beneficial microorganisms helps to improve the trees’ health.

A well-known biocontrol agent, Trichoderma, appeared to be related to the absence or scarcity of oomycete pathogens. What is more, an abundance of mycorrhizae resulted in less defoliation of the woodland. These microorganisms are able to establish antagonistic relationships with the pathogens, increase a tree’s ability to absorb and stimulate an autoimmune response. In other words, a structure conducive to the fungi community and the presence of key beneficial species provide the oak with more resources to defend itself from the pathogen and improve the health of a woodland, even when root rot is present.

Turning the focus underground also unravels other mysteries. All of the lands that were studied had root rot (decline), and nevertheless, the pathogens that are considered to be the main causes of the disease were not relevant on many plots of land, despite them being teeming with dying holm oaks. The key to this mystery was the presence of a mixture of less aggressive individual species such as Alternaria and Fusarium among others. When these kinds of species synergize, they can cause the same symptomatology as do more aggressive species, even to the point that they cause the tree to die. So, UCO and IFAPA researchers concluded that a diagnosis of oak decline should not only be limited to the presence of one single pathogen, but rather a complete analysis of the present communities and the relationships among them is required in order to detect danger in a more precise way.

Advances in technology is what has allowed for solving the complexity of this study. The research group applied plant biotechnology methods to the study of forest pathology, which along with being able to access data from the Environmental Damage Tracking Network, part of the Andalusian Regional Government, allowed for understanding the role of soil microorganisms in the decline of Andalusian dehesas. The diversity and structure of microbiota is a key piece to this puzzle. Considering the soil microbiome within the comprehensive management of holm oak and cork oak root rot on the dehesa is bringing the research community closer to finding the solution that will most effectively protect this ecosystem.

Read the paper: Scientific Reports

Article source: University of Cordoba

Image: University of Cordoba

While the fate of most human cells is determined by their lineage—for example, renal stem cells go on to form the kidney while cardiac progenitor cells form the heart—plant cells are a little more flexible. Research shows that although they undergo orderly division during growth, the fate of plant cells is often determined by their location in the growing plant rather than how they started out. Intriguingly, this suggests that plant cells recognize where they are and can alter gene activity in response to their location.

To investigate position-dependent gene expression in plants, Hiroyuki Iida, Ayaka Yoshida, and Shinobu Takada from the Department of Biological Sciences at Japan’s Osaka University studied the differentiation of shoot epidermal cells in model plant Arabidopsis thaliana. Publishing in a recent issue of Development, the researchers showed that in plants, location really is everything.

“Many land plants have a single layer of epidermal cells to protect themselves from dehydration. However, it is not known how only the outermost cells are differentiated into the epidermis,” explains lead author Iida. To examine the differentiation process, the researchers focused on a protein called ATML1, which helps determine epidermal cell identity in the shoots of plants.

“We found that although the ATML1 gene was expressed in subepidermal cells, there was a much greater accumulation of ATML1 protein in the outermost cell layer, suggesting that protein accumulation was inhibited in the internal cell layers,” says Iida.

By tagging the proteins with a fluorescent dye, the researchers could also examine where ATML1 was located inside the cells. Interestingly, while the fluorescent protein was most frequently found in the nucleus of the outermost cells, nuclear accumulation of ATML1 was weak in the inner cells, meaning that it could not interact with genes necessary for epidermal cell differentiation.

Going one step further, the researchers were even able to show that a section of the ATML1 protein called the ZLZ domain was necessary, but not entirely responsible for, the reduced nuclear accumulation and activity of ATML1 in the inner cells.

“Our study shows that post-transcriptional regulation of ATML1 based on the location of the cells is likely to be responsible for the formation of the single epidermal layer seen in many seed plants,” says senior author of the study Dr Shinobu Takada. “These findings provide greater insight into plant morphogenesis and help us to understand the evolutionary processes by which land plants have acquired the epidermis.”

Read the paper: Development

Article source: Osaka University

Image: Osaka University

Scientists at Lobachevsky University have proved the possibility of using yellow-green light pulses to measure the photochemical reflectance index and to estimate the amount of light stress in agricultural plants

Precision farming, which relies on spatially heterogeneous application of fertilizers, biologically active compounds, pesticides, etc., is one of the leading trends in modern agricultural science.

A necessary condition for such farming is a quick and remote analysis of the state of plants in the fields and greenhouses. To solve this problem, various spectral indices based on measurements of reflected light in narrow spectral bands are widely used. One of these indices, currently in the focus of attention of Lobachevsky University researchers, is the photochemical reflectance index – PRI.

The photochemical reflectance index is determined by measuring reflected light at two wavelengths in the yellow-green spectral range, at 531 and 570 nm, which is carried out using special detectors or multispectral cameras.

“A unique feature of the photochemical reflectance index is its sensitivity even to weak stress-related changes in the state of the photosynthetic apparatus. This opens up the potential possibility of using the photochemical reflectance index for early and remote diagnosis of how adverse factors may affect plants. However, the use of PRI has a number of serious limitations, one of them being the high sensitivity of the index to the lighting conditions, which is especially important if the measurements take place under solar lighting conditions,” says Vladimir Sukhov, head of the UNN plant electrophysiology laboratory.

This problem is addressed in the research project carried out by Ekaterina Sukhova, graduate student at the Department of Biophysics Lobachevsky University. The project was supported by the Russian Science Foundation (project No. 17-76-20032, supervisor Vladimir Sukhov). Research results were published in one of the leading scientific journals in the field of remote monitoring – Remote Sensing, 2019, 11 (7): 810.

For this purpose, Lobachevsky University scientists proposed an idea that could potentially reduce the sensitivity of the photochemical reflectance index to lighting conditions. It is based on the use of periodic illumination of the plant by pulses of yellow-green measuring light from a source with known spectral characteristics.

The intensity of the reflected light is calculated as the difference between the reflected light during each pulse of yellow-green light and before such a pulse (Fig. 1), which allows one to eliminate the influence of other light sources on the measurement results. Ekaterina Sukhova’s research has proved that the use of yellow-green light pulses eliminates the distorting effects of other light sources on the measurement of the photochemical reflectance index, and therefore improves the accuracy of determining the PRI.

Further, the photochemical reflectance index was determined under conditions of stress-inducing light intensities in a number of agricultural plants and was compared with the generally accepted indicator of photosynthetic stress — non-photochemical quenching of chlorophyll fluorescence (Fig. 2).

“It appears that both indicators are closely related, which is confirmed by the use of the photochemical reflection index that was measured using yellow-green light pulses to assess the severity of photosynthetic stress of agricultural plants. The magnitude of the change in the photochemical reflectance index, which is linearly related to the intensity of stress on the plants under study, is a particularly effective indicator,” Ekaterina Sukhova comments.

On the whole, Lobachevsky University researchers obtained two significant results. First, it was shown that the use of periodic pulses of yellow-green light reduces the error in measuring the photochemical reflectance index and, secondly, scientists have found that the change of the PRI in the light is a more reliable indicator of the severity of photosynthetic stress in a plant than its absolute magnitude.

“These results provide the basis for a new approach to measuring the photochemical reflectance index, which involves pulsed illumination of the plant objects under study. The implementation of this approach opens up new prospects in remote monitoring of the state of agricultural plants. It means that this method will become an important tool in precision farming,” continues Ekaterina Sukhova.

Currently, scientists at Ekaterina Sukhova and their colleagues from the Institute of Applied Physics of the Russian Academy of Sciences are working to further develop the proposed method and to adapt it for measuring the spatial distribution of the photochemical reflectance index.

“In particular, a PRI imaging system based on the illumination of objects under study with pulses of yellow-green light has already been developed and is being tested. It is expected that the prototype already developed will become the basis for a commercial system for assessing the state of plants based on measuring the spatial distribution of the photochemical reflectance index,” Ekaterina Sukhova concludes.

Read the paper: Remote sensing

Article source: Lobachevsky University

Image: Lobachevsky University

Abortion of seeds with extra genomes is caused by the enzyme RNA Pol IV

In flowering plants, the embryo is surrounded by the endosperm. Endosperm tissue mediates nutrient transferbetween the growing embryo and the mother. The endosperm is distinct from the rest of the plant because it has onlyonecopy of the father’s genome and two copies of the mother’s. The ratio of maternal to paternal genomes is remarkable because of its importance to seed viability and development. Seeds with extra genomes that alter this critical ratio undergo a process known as interploidy seed abortion due to defective endosperm development. RNA Pol IV isan enzyme specific to plant genomes thatgeneratessmall RNA molecules thatsilence gene expression from transposons and repetitive DNA, playing a major role in defending the genome against viruses and transposable elements. The new work shows that RNA Pol IVplays akeyrole ininterploidy seed abortion.

This research, coauthored by P.R.V. Satyaki and Mary Gehring of the Whitehead Institute for Biomedical Research, focused on the following questions: How does the lack of RNA Pol IV prevent interploidy seed abortion? Where does RNA Pol IV act,in the endosperm or in the father,to influence gene expression in the endosperm? In what genetic pathway does RNA Pol IV function to cause seed abortion?Arabidopsis plants going to seed.

In this article, Satyaki and Gehring demonstratethat RNA Pol IV targetsgenes in the fatherviathe “canonical” RNA-directed DNA methylation pathway, a major gene-silencing pathway in Arabidopsis plants, resulting in interploidy seed abortion. The researchers compared gene transcription in the endosperm of aborted interploidy seeds with that of seedsthat were viable due tothe loss of paternal RNA Pol IV. The researchers found that transposons and thousands of genes, even imprinted ones, were misregulated in both living and dying seeds. Theresearchers learned that misregulation of a relatively small number of genes setsliving seeds apart from aborting ones.

This study is also important because it identified atranscriptional buffering system in the endosperm. This system counteractsthe effects of a higher dose of the paternal genome byreducingthe expression of the paternal copiesof some genes and increasingthe expression of maternal copies ofother genes.

First author P.R.V. Satyaki said: “The next steps are to unravel the mechanism underlying the transcriptional buffering system and to identify the genes responsible for interploidy seed abortion using the shortlist of candidate genes generated from our transcriptional studies.”

Read the paper: The Plant Cell

Article source: ASPB

Image: Conor Gearin/Whitehead Institute

Researchers from Australia, Germany, Switzerland and the US have quantified the effect of climate extremes, such as droughts or heatwaves, on the yield variability of staple crops around the world.

Overall, year-to-year changes in climate factors during the growing season of maize, rice, soy and spring wheat accounted for 20%-49% of yield fluctuations, according to research published in Environmental Research Letters.

Climate extremes, such as hot and cold temperature extremes, drought and heavy precipitation, by themselves accounted for 18%-43% of these interannual variations in crop yield.

To get to the bottom of the impacts of climate extremes on agricultural yields, the researchers used a global agricultural database at high spatial resolution, and near-global coverage climate and climate extremes datasets. They applied a machine-learning algorithm, Random Forests, to tease out which climate factors played the greatest role in influencing crop yields.

“Interestingly, we found that the most important climate factors for yield anomalies were related to temperature, not precipitation, as one could expect, with the average growing season temperature and temperature extremes playing a dominant role in predicting crop yields,” said lead author Dr. Elisabeth Vogel from the Centre of Excellence for Climate Extremes and Climate & Energy College at the University of Melbourne.

The research also revealed global hotspots – areas that produce a large proportion of the world’s crop production, yet are most susceptible to climate variability and extremes.

“We found that most of these hotspots – regions that are critical for overall production and at the same time strongly influenced by climate variability and climate extremes – appear to be in industrialised crop production regions, such as North America and Europe.”

For climate extremes specifically, the researchers identified North America for soy and spring wheat production, Europe for spring wheat and Asia for rice and maize production as hotspots.

But, as the researchers point out, global markets are not the only concern. Outside of these major regions, in regions where communities are highly dependent on agriculture for their livelihoods, the failure of these staple crops can be devastating.

“In our study, we found that maize yields in Africa showed one of the strongest relationships with growing season climate variability. In fact, it was the second highest explained variance for crop yields of any crop/continent combination, suggesting that it is highly dependent on climate conditions,” Dr Vogel said.

“While Africa’s share of global maize production may be small, the largest part of that production goes to human consumption – compared to just 3% in North America – making it critical for food security in the region.”

“With climate change predicted to change the variability of climate and increasing the likelihood and severity of climate extremes in most regions, our research highlights the importance of adapting food production to these changes,” Dr Vogel said.

“Increasing the resilience to climate extremes requires a concerted effort at local, regional and international levels to reduce negative impacts for farmers and communities depending on agriculture for their living.”

Read the paper: Environmental Research Letters

Article source: University of New South Wales

Image: Hans Braxmeier / Pixabay

For the very first time, researchers from the University of Bristol have measured farmland nectar supplies throughout the whole year and revealed hungry gaps when food supply is not meeting pollinator demand. This novel finding reveals new ways of making farmland better for pollinators, benefitting the many crop plants and wildflowers that depend on them.

Planting wildflower strips is a common strategy for providing pollinators with more food on farmland. These can provide plenty of pollen and nectar for bees to feed on, but most of this food supply is limited to the late spring and early summer when there is already plenty to eat. A new study published in the Journal of Applied Ecology found that early spring (March) and late summer (August-September) are periods of great nectar deficit on UK farmland.

Jane Memmott, Professor of Ecology from Bristol’s School of Biological Sciences and principal investigator, explained: “It’s not just how much nectar there is that matters, but what time of year that nectar is available.

“If a bumblebee queen comes out of hibernation in March and finds nothing to eat, it doesn’t matter how much nectar there is in summer, because she won’t be alive.”

Pollinators such as bees, flies and wasps require a constant supply of nectar throughout the year to stay alive, fly around and pollinate important crops and wild plants.

Tom Timberlake, PhD researcher at the University of Bristol and lead author, added: “By identifying these hungry gaps and finding plants to fill them, we could create a more consistent supply of pollen and nectar, allowing more pollinators to survive through the year.

“Early-flowering plants like willows and dandelions, or late-flowering red clover and ivy could all help to fill the hungry gaps, if we allow them to survive and flower on farmland.”

Pollinators such as bees are critical for the reproduction of most crop plants, including many of our favourites such as strawberries and coffee. Their services are worth up to $500 billion US each year but are under increasing threat as pollinators face worldwide declines. Providing more pollen and nectar rich flowers on farmland is certainly part of the solution. But this new research shows that if we want to be most effective, we must consider the timing of both food supply and pollinator demand.

Read the paper: Journal of Applied Ecology

Article source: University of Bristol

Image: Tom Timberlake

In an unusual new study, scientists say they have detected the fingerprint of human-driven global warming on patterns of drought and moisture across the world as far back as 1900. Rising temperatures are well documented back at least that far, but this is the first time researchers have identified resulting long-term global effects on the water supplies that feed crops and cities. Among the observations, the researchers documented drying of soils across much of populous North America, central America, Eurasia and the Mediterranean. Other areas, including the Indian subcontinent, have become wetter. They say the trends will continue, with severe consequences for humans. The study appears in the leading journal Nature.

In general, scientists agree that as global warming progresses, many now dry regions will become drier, and wet ones will become wetter. Some recent studies suggest that human-induced warming has intensified droughts in particular regions, including a now near 20-year ongoing drought in the southwestern United States. However, the last report by the Intergovernmental Panel on Climate Change says confidence in attributing specific ongoing events directly to humans is still chancy.

The new study combines computer models with long-term observations to suggest that systemic changes in what scientists call the hydroclimate are already underway across the world, and have been for some time. The researchers looked not simply at precipitation, but rather soil moisture, a more subtle measure that balances precipitation against evaporation, and is the quality most directly relevant to farming and forestry. They used tree rings going back 600 to 900 years to estimate soil moisture trends before human-produced greenhouse gases started rising, then compared this data with 20th-century tree rings and modern instrumental observations, to see if they could pick out drought patterns matching those predicted by computer models, amid the noise of natural yearly or decadal regional weather variations.

“We asked, does the real world look like what the models tell us to expect?” said study coauthor Benjamin Cook of the NASA Goddard Institute for Space Studies and Columbia University’s Lamont-Doherty Earth Observatory. “The answer is yes. The big thing we learned is that climate change started affecting global patterns of drought in the early 20th century. We expect this pattern to keep emerging as climate change continues.”

Lead author Kate Marvel, a climate modeler at Goddard and Columbia University, said, “It’s mind boggling. There is a really clear signal of the effects of human greenhouse gases on the hydroclimate.”

Soil moisture is a complex issue, because precipitation and evaporation can work with each other, or against each other. Warmer air can carry more moisture, and thus more rain or snow. But warmer air can also evaporate more moisture from soil and carry it away, outweighing precipitation. That is probably the factor now at work in the drying western United States, and possibly other locations that have seen recent big droughts. “Precipitation is just the supply side,” said study coauthor Jason Smerdon, a Lamont-Doherty paleoclimatologist. “Temperature is on the demand side, the part that dries things out.” Which part predominates depends on complex factors including wind patterns, seasons, clouds, topography and proximity to the moisture-giving oceans.

The scientists identified three distinct periods in their study. The first was 1900 to 1949, when they say the global-warming fingerprint was the most obvious. During this time, as predicted by models, drying was seen in Australia, much of central America and North America, Europe, the Mediterranean, western Russia and southeast Asia. At the same time, it got wetter in western China, much of central Asia, the Indian subcontinent, Indonesia and central Canada.

From 1950 to 1975, the pattern scattered into seemingly random events. The scientists believe this might be related to enormous amounts of industrial aerosols then being poured into the air without modern pollution controls. These can affect regional cloud formation, rainfall and temperature, by, among other things, blocking solar radiation and providing nuclei for moisture droplets. The researchers believe that the complex effects of aerosols probably threw a monkey wrench into the weather in many places, masking the effects of greenhouse gases, even though those gases continued to rise.

Then, starting in the 1970s, many industrial countries including the United States started instituting progressively stricter clean-air laws. Even though industrial activities continued to grow, aerosols quickly leveled off or slightly declined in many places. But at the same time, greenhouse-gas emissions continued spiraling up, along with temperatures. As a result, the researchers say, the global-warming signature on hydroclimate began re-emerging around 1981. The signal is not yet as obvious as it was in the early 20th century, but it continues to rise, especially since around 2000.

“If we don’t see it coming in stronger in, say, the next 10 years, we might have to wonder whether we are right,” said Kate Marvel. “But all the models are projecting that you should see unprecedented drying soon, in a lot of places.”

Many of the areas expected to dry out are centers of agricultural production, and could become permanently arid. “The human consequences of this, particularly drying over large parts of North America and Eurasia, will likely be severe,” says the study.

Precipitation over much of central America, Mexico the central and western United States and Europe is projected to stay about the same, or even increase. But, according to both the new study and a separate 2018 paper, rising temperatures and resulting evaporation of moisture from soils in those regions will probably predominate. The Mediterranean region is expected to be hit with a double whammy of both less rainfall and more heat-driven evaporation. Adding to the drought dynamics of all the affected areas: populations are expected to continue increasing, adding to water demand. According to an earlier Lamont-Doherty study, a 2006-2010 drought leading up to the disastrous Syrian civil war was probably made more likely by warming climate, and the drought may have helped create the social and economic conditions that sparked the initial rebellion.

Some areas are expected to get wetter, but this may not necessarily be good. India and some surrounding nations are expected to get more rain, because they sit squarely in the path of monsoon winds that pick up moisture from the Pacific and Indian oceans, and those oceans are getting warmer. But the rain may come perhaps more often in overwhelming storms, and not necessarily at times when it is needed.

The new study was made possible in part by recently published atlases of tree-ring chronologies from thousands of sites around the world, going back as far as 2,000 years. These gave the researchers a baseline of how weather varied before humans started heavily affecting it. The atlases are largely the work of Lamont-Doherty scientist Edward Cook, father of study coauthor Benjamin Cook. The North American drought atlas came out in 2004, followed by a Monsoon Asia atlas in 2010, and compilations for Europe and the Mediterranean, Mexico and Australia/New Zealand in 2015. (One for South America is on the way; much of Africa still remains uncovered.)

“This important paper offers new insights into the link between increasing atmospheric greenhouse gases and regional droughts, both in the past and increasingly in the future,” said Peter Gleick, cofounder of California’s Pacific Institute, and expert on climate and water issues. “It also confirms the growing sophistication of our climate models and improves the tools available to detect and identify the fingerprint of human impacts on extreme hydrologic events.”

The study was coauthored also by Céline Bonfils and Paul Durack of Lawrence Livermore National Laboratory, and A. Park Williams of Lamont-Doherty.

Read the paper: Nature

Article source: Columbia University

Image: Kevin Krajick/Earth Institute