Researchers from the National University of Singapore (NUS) have discovered a salt adaptation mechanism in plants that facilitates chloride removal from the roots and enhances salinity tolerance. The work was published in the journal Nature Communications.

Soil salinity is one of the most deleterious environmental stress factors and increased salinity poses a growing challenge for crop production and adversely affects crop yields worldwide. The excess accumulation of soluble salts, especially sodium chloride (NaCl), in the root zone severely impedes plant growth, reducing crop productivity. Although chloride ions (Cl^–) are essential nutrients for plants at low concentrations, their excessive accumulation is toxic to the plant cells.

Plants have evolved various strategies to cope with such environmental stresses by employing various channels and transporters for maintaining ion balance (ion homeostasis) in their cells. While there is a better understanding of the sodium ion homeostasis under salt stress, removal of chloride ions is not well understood.

To address this, a research team led by Professor Prakash Kumar from the Department of Biological Sciences, NUS has uncovered a novel mechanism of plant adaptation to salt stress involving the NaCl-induced translocation of a specific chloride channel protein, AtCLCf.

Their work revealed that the AtCLCf protein is made and stored in the endomembrane system (the Golgi apparatus) under normal growth conditions. When the root cells are treated with salt, AtCLCf translocates to the plasma membrane (PM), where it helps to remove the excess chloride ions. This represents a novel mechanism to increase the plant’s salinity tolerance.

The research is a collaboration with Dr. Jiří Friml from the Institute of Science and Technology, Austria and Professor Xu Jian from Radboud University, The Netherlands.

The study also identified a transcription factor, AtWRKY9, that directly regulates the expression of the AtCLCf gene when the plant is under salt stress.

NaCl causes the AtCLCf protein to move from inside the cell (the Golgi) to the cell surface with the help of another protein called AtRABA1b/BEX5. If this movement is blocked by an inhibitor (brefeldin-A) or by modifying the BEX5 gene, it results in high salt sensitivity in plants.

Transgenic plants designed to produce additional AtCLCf gene showed increased salt tolerance in mutant forms of Arabidopsis plants lacking the CLCf gene. Collectively, these findings proved that AtCLCf is involved in the removal of excess chloride ions from root tissues to increase the salt tolerance of plants.

In order to understand how AtCLCf functions in plant cells, the researchers used several techniques such as fluorimetric measurement of liposomes incorporated with recombinant AtCLCf protein and chloride ion sensitive dye, as well as electrophysiological studies (patch clamp). These studies showed that AtCLCf works like a pump that swaps chloride ions with hydrogen ions, helping to remove excess chloride ions from the cells.

Prof Kumar said, “This represents an essential and previously unknown salt tolerance mechanism in Arabidopsis plants. This knowledge could be used to improve the salinity tolerance of crop plants in the future.”

There is a common belief that prescribed burning, thinning trees, and clearing underbrush reduce risks of the severity of future fires. But is that true? Sometimes anecdotal evidence or limited observations can create doubt.

Researchers from the USDA Forest Service Rocky Mountain Research Station, The Nature Conservancy, and the University of Montana dug deep into the scientific literature for a closer look. Spoiler alert: the answer is “yes”—proactive ecological forest management can change how fires behave and reduce wildfire severity, under a wide range of conditions and forest types.

Researchers found overwhelming evidence that in seasonally dry mixed conifer forests in the western U.S., reducing surface and ladder fuels and tree density through thinning, coupled with prescribed burning or pile burning, could reduce future wildfire severity by more than 60% relative to untreated areas.

The study results were published in Forest Ecology and Management. “Burning Questions Answered: New review examines 30 years of fuel treatment effects on wildfire severity” includes an overview of the research methods, key findings, management considerations, and links to related publications.

Fire is an essential component of many western forests. Yet historic fire suppression and climate change are contributing to increased fire activity and more severe wildfires, where overstory trees are killed. Treatments prepare a landscape, priming the next wildfire to burn at lower intensity, burning underbrush and smaller trees. This preserves more mature trees and helps foster a fire level that is more in balance with the landscape.

Kimberley Davis is a Forest Service Research Ecologist and led the project analyzing 40 studies where wildfire burned into different vegetation treatments, spanning 11 western states. The last review of this kind was over a decade ago, with many new case studies and scientific advances since then. Researchers examined effects of various treatments in different forest types, ranging from ponderosa pine forests in Arizona and New Mexico up to the subalpine zones of the northern Rocky Mountains.

The review hands natural resource professionals and communities the evidence needed to support continued investments in managing vegetation and fuels. “These treatments are very effective and the science clearly shows that they can reduce fire severity,” said Davis.

While responses varied, generally the combination of thinning and prescribed burning showed the greatest impact on reducing future fire severity. Areas that were only thinned had less benefit in reducing wildfire severity. Prior low or moderate severity wildfire also reduced fire severity in subsequent wildfires, although to a lesser extent than thinning with prescribed burning.

Time also matters. “As treatments get older, they’re less effective,” said Davis. After 10 years treatments were less than half as effective as younger treatments, underscoring the importance of repeated or “maintenance” treatments.

In the long run, forest fuel reduction projects can improve conditions for fire fighters responding to wildfires. They mitigate long-term losses of carbon and wildlife habitat and protect watersheds from more severe wildfire. Treatments also create more options for determining appropriate responses to lightning and other unplanned ignitions.

When designed to meet the unique needs of the forest type and nearby communities, these tools can support the longevity of clean water resources, wildlife habitat, and outdoor places to work and recreate.

“This review shows that treatments can reduce future wildfire severity, which is key to protecting important forest habitats,” said Kerry L. Metlen, forest ecologist with The Nature Conservancy and a contributing author of the review.

“This gives us hope that by accelerating the use of these tools, in conjunction with work to promote fire adapted communities, we can address the wildfire crisis together.”

The diversity of forms of living organisms is enormous. But how the individual cells together coordinate the formation of organs and tissues in complex organisms is still an open question.

Researchers at the Max Planck Institute for Plant Breeding Research in Cologne, Germany, have discovered a genetic mechanism that changes the direction of growth of plant cells during leaf development and thus determines the shape of a leaf.

Miltos Tsiantis and his group from the Max Planck Institute for Plant Breeding Research want to find out how biological forms develop and the basis for their diversity. The researchers are using thale cress (Arabidopsis thaliana), as the genome and development of this small garden weed have been studied intensively for many years.

By comparing it with its close relative, the hairy bittercress (Cardamine hirsuta), which has leaves formed of individual leaflets rather than the simple spoon-shaped leaves of Arabidopsis, the researchers want to find out how different leaf shapes develop.

The findings are published in the Proceedings of the National Academy of Sciences.

Leaf growth is controlled by the hormone auxin: Leaves, leaflets or flowers develop in areas with a high auxin concentration. Where the hormone accumulates is determined by the activity of the PIN1 protein, which transports auxin out of the cells. The PIN1 transporters are not evenly distributed over the surface of a cell, but can be concentrated on the upper or lower side, for example. This asymmetry is decisive for where auxin acts.

PIN1 distribution can also be altered to create an on/off growth pattern, for example in the arrangement of leaves along a stem. This ability of PIN1 and auxin to organize plant growth has been known for some time.

“However, we know very little about how different distributions of the PIN1 transporter are controlled, and how different growth patterns are triggered in cells, which then ultimately determine the shape of a leaf,” explains Tsiantis.

The researchers used state-of-the-art microscopes to visualize individual cells in plants and created time-lapse images of leaf development that allow them to measure the growth of every cell on the leaf surface. By using fluorescent proteins to tag the products of the genes they are interested in, they can also observe which genes are active, when and where in the cells.

Working together with Adam Runions from the University of Calgary, the researchers then use this biological data to generate computer models that allow them to simulate the genetic interactions that ultimately control growth patterns in leaves.

Genetic switch controls where auxin will accumulate

During their investigations of their two model plants, the team discovered a genetic switch involving a gene called CUC1. When activated, this switch can influence where in a cell the transporter PIN1, and subsequently the growth hormone auxin, will accumulate.

CUC1 is not active in the simple leaves of Arabidopsis. In hairy bittercress, however, CUC1 leads to the formation of leaflets. “We found that this CUC1-dependent switch instructs cell growth to take place in a specific pattern, which in the hairy bittercress allows its complex leaf shape to develop,” explain researchers Ziliang Hu and David Wilson-Sánchez, the lead authors of the study. “When we activate CUC1 in Arabidopsis thaliana, it also forms more complex leaves.”

Their experiments not only help explain the different leaves of the two plant species studied, they also demonstrate how a genetic switch can affect the polarity and growth of individual cells in a coordinated manner, and thus lead to the formation of complex shapes.

“With this work, we now have a much clearer picture of the fundamental mechanisms that operate in cells to generate the forms of plants and their diversity,” says Tsiantis.

Non-Indigenous scientists increasingly realize that Indigenous data are key to solving today’s environmental challenges.

Indigenous Peoples have generated and cared for data for millennia, passing down knowledge through traditions like storytelling, art and language. This knowledge is crucial to Indigenous ways of life, including the sustainable stewardship of ecosystems.

With partnerships between non-Indigenous scientists and Indigenous knowledge holders proliferating, incorporating Indigenous data sovereignty (IDS)—the right of Indigenous Peoples to govern the collection, ownership and application of their data—is vital for successful collaborations and conservation.

Science and Indigenous data

Non-Indigenous scientists have a troubling track record of unethical research practices.

Examples of treating Indigenous knowledge holders as research subjects are common and often lead to exploitation, mistrust and ongoing power imbalances that persist today. For instance, Indigenous data—which includes information about an Indigenous Nation and its land, resources, demographic data, education levels, sacred land maps, songs, social media, and beyond—may be used without proper acknowledgement constituting the theft and exploitation of Indigenous knowledge and resources.

Transparent collaborations between external researchers and Indigenous Peoples are a positive development. However, collaborations can also place pressures on Indigenous knowledge holders and communities. These pressures can compound stresses upon communities who are at the same time also dealing with the legacies of violent colonial dispossession and navigating environmental harms and injustices largely not of their own making.

Indigenous rights to data sovereignty are recognized by the United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP). UNDRIP is further affirmed as federal law through Canada’s United Nations Declaration on the Rights of Indigenous Peoples Act and encoded as provincial law in B.C. through the Declaration on the Rights of Indigenous Peoples Act.

Growing recognition that Indigenous data can inform environmental stewardship has only added to pressures on Indigenous knowledge holders and communities to publicize their data. Meanwhile, the open data and big data movements—which aim to make data widely accessible and combine data from various sources to address societal issues—is simultaneously pressuring Nations to release control.

While open data offers benefits like accountability and broader analyses, it also puts Indigenous Peoples’ control over their data at risk.

Exclusion of Indigenous data from data-sets marginalizes Indigenous communities, while inclusion without proper guidance perpetuates biases and removes data from their cultural contexts. Initiatives like the First Nations Principles of OCAP and the CARE Principles integrate Indigenous perspectives into data governance and offer a path toward aligning open data practices with Indigenous sovereignty.

IDS in British Columbia

Efforts to protect wild Pacific salmon populations in B.C. demonstrate the importance of IDS for conservation.

Pacific salmon are essential for healthy ecosystems and hold deep cultural significance for Indigenous Peoples across Western Canada. Threats to salmon, spanning freshwater and marine habitats, are complex and diverse.

For millennia before colonization, many First Nations in B.C. utilized data to manage salmon fisheries sustainably. Today, the reliance on industry data by government regulators like Fisheries and Oceans Canada poses risks to salmon populations and undermines Indigenous stewardship.

In June 2022, we were a part of an online webinar hosted by the Watershed Futures Initiative at Simon Fraser University that brought together First Nations knowledge holders and technical staff to discuss these challenges in the context of wild Pacific salmon in B.C.

The findings of this event were recently published in Facets and include potential steps for First Nations governments to take in asserting sovereignty over their data. Additionally, there are also recommendations that external researchers can follow to ensure they respect IDS and maintain ethical data management.

For example, First Nations may want to create steps or policies for external researchers or neighboring Nations to follow when requesting access to their data or territories. Nations may also want to create tools supporting data collection, management and dissemination, or consider using outside tools to help manage data.

Meanwhile, non-Indigenous researchers must educate themselves about IDS, engage with First Nations before planning research or monitoring, and avoid making assumptions about ownership and data management. They can also find ways to direct funding and resources to Nations and advocate for changing policies within and beyond their organizations or institutions.

To support these efforts, we created an Indigenous Data Sovereignty toolkit with links for further reading, third-party tools for data management, template data agreements and more.

Moving forward

Indigenous Peoples are global leaders in environmental justice and conservation, yet discussions about collaborative research often overlooks the importance of IDS. Meanwhile, the push for open data policies may disregard Indigenous rights and undermine efforts to protect Indigenous data.

We call for greater consideration of IDS in research, conservation and governance arrangements. Scientists must integrate IDS into research partnerships to support Indigenous sovereignty and facilitate more successful conservation outcomes. At the same time, Crown decision-makers must establish governance agreements with Nations that respect and value Indigenous data sovereignty.

IDS is imperative for equitable and sustainable conservation efforts, paving the way for a future where ecosystems flourish, wildlife thrives and communities prosper.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

A new peer-reviewed study from researchers at The University of Texas at Arlington; the University of Nevada, Reno; Mokwon University in Daejeon, Korea; and Texas A&M University at Corpus Christi shows the Deepwater Horizon (DWH) oil spill of 2010 affected wildlife and their habitat much more than previously understood.

The work is published in the journal Marine Pollution Bulletin.

“Overall, we found the area of deep-sea floor affected by the DWH spill was significantly larger than previously thought,” said Masoud Rostami, an author of the study and assistant professor of instruction in UTA’s Division of Data Science.

In recent decades, deep-water ecosystems in lakes, oceans, and seas around the world have faced pressures from offshore oil and gas production, including frequent contamination from oil and other pollutants. The DWH oil spill in the Gulf of Mexico that started on April 20, 2010, was the largest marine oil spill in U.S. history, releasing nearly 5 million barrels of crude oil and hydrocarbon gases over 87 days, with 3.2 million barrels of oil remaining in the water after cleanup efforts.

This spill greatly exceeded the amount of natural discharge of oil that seeps in the Gulf each year, and up to 35% of the pollutants were trapped below the surface, severely impacting the lives and habitats of the plants, animals, and microorganisms (like bacteria and fungi) that live deep in the ocean. For this study, the researchers focused on the harpacticoid copepods, a type of crustacean that lives near the bottom of the ocean, to better understand the DWH spill’s effects on the deep-sea ecosystem in the Gulf of Mexico. Copepods are good for this type of study because they live in several different deep-sea habitats and are known to be sensitive to pollution.

Researchers found that the spill affected biodiversity over an area of 1,100 square miles—a area nearly nine times larger than earlier studies on DWH. Using advanced methodologies, including remote sensing, multivariate statistical analysis, and machine-learning approaches, the team detected subtle changes in the deep-sea copepod community composition.

“This study demonstrates that harpacticoid copepod diversity dramatically declined because of DWH oil pollution,” said Rostami.