Scientists call for soil mapping program to help Indian agriculture

Delegates to the University's agriculture workshop at Kharagpur

Scientists attending an agriculture workshop in India organised by the University of Sydney have called for a detailed soil mapping program to help policy makers and farmers draw up effective land management proposals.

The Soil and Water National Networking Workshop, organised jointly with the Indian Institute of Technology at Kharagpur, involved 40 scientists from India and Australia.

They discussed key issues including soil security, digital soil mapping, India's participation in the Global Soil Map project, national level spectral libraries, soil data requirement in crop simulations, soil health mapping, hydrological model behaviour, and using soil digital and satellite data for hydrologic models.

A number of speakers urged India to participate in the Global Soil Map and accelerate the provision of fine scale information on soil fertility and conditions in India. The information could also be used to monitor and understand the change over time in soil nutrients.

The workshop's soil group was led by Professor Budiman Minasny, Professor Bhabani Das and Dr Kanika Singh from the University of Sydney. The hydrology group was led by A/Professor Willem Vervoort from Sydney, Dr Rajib Maity and Mr Dipangkar Kundu.

The workshop was launched with a welcome video by Professor Alex McBratney, the Dokuchaev award winner in Soil Science, who is actively involved with the Global Soil Map.

Dr Singh said: "The workshop was a great success; the Indian scientists showcased high quality research and are open to future collaboration in the Global Soil Map effort.

"The director of IIT Kharagpur in his speech talked about a joint collaboration between India and Australia for a comprehensive digitisation of soil information contributing to soil security and sustainable productivity. The Assistant Director General of the Indian Council of Agricultural Research is also keen to developIndian collaboration in the Global Soil Map effort.

"We look forward to long-term collaboration with IIT Kharagpur and other such organisations in India to achieve collaborative research."

The workshop was sponsored by the Australia-India Council.

Contact: Richard North
Phone: 02 9351 3191
Email: richard.north@sydney.edu.au

 Source: THE UNIVERSITY OF SYDNEY

For tiger populations, a new threat

This is an Amur tiger photographed by camera trap. Credit: WCS Russia Program

Along with the pressures of habitat loss, poaching and depletion of prey species, a new threat to tiger populations in the wild has surfaced in the form of disease, specifically, canine distemper virus (CDV). According to a new study from the Wildlife Conservation Society (WCS) and its partners, CDV has the potential to be a significant driver in pushing the animals toward extinction.

While CDV has recently been shown to lead to the deaths of individual tigers, its long-term impacts on tiger populations had never before been studied.

The authors evaluated these impacts on the Amur tiger population in Russia's Sikhote-Alin Biosphere Zapovednik (SABZ), where tiger numbers declined from 38 individuals to 9 in the years 2007 to 2012. In 2009 and 2010, six adult tigers died or disappeared from the reserve, and CDV was confirmed in two dead tigers -- leading scientists to believe that CDV likely played a role in the overall decline of the population. Joint investigations of CDV have been an ongoing focus of WCS and Russian scientists at Sikhote-Alin Zapovednik and veterinarians at the regional Primorye Agricultural College since its first appearance in tigers in 2003.

A key finding of this study: Modeling shows that smaller populations of tigers were found to be more vulnerable to extinction by CDV. Populations consisting of 25 individuals were 1.65 times more likely to decline in the next 50 years when CDV was present. The results are profoundly disturbing for global wild tigers given that in most sites where wild tigers persist they are limited to populations of less than 25 adult breeding individuals.

The scientists used computer modeling to simulate the effects of CDV infection on isolated tiger populations of various sizes and through a series of transmission scenarios. These included tiger-to-tiger transmission and transmission through predation on CDV-infected domestic dogs and/or infected wild carnivores (such as foxes, raccoon dogs and badgers). High and low-risk scenarios for the model were created based on variation in the prevalence of CDV and the tigers' contact with sources of exposure.

Results showed that CDV infection increased the 50-year extinction probability of tigers in SABZ as much as 55.8 percent compared to CDV-free populations of equivalent size.

"Although we knew that individual tigers had died from CDV in the wild, we wanted to understand the risk the virus presents to whole populations," said WCS veterinarian Martin Gilbert. "Tigers are elusive, however, and studying the long-term impact of risk factors is very challenging. Our model, based on tiger ecology data collected over 20 years in SABZ, explored the different ways that tigers might be exposed to the virus and how these impact the extinction risk to tiger populations over the long term."

WCS Russia Program Director Dale Miquelle said, "Tigers face an array of threats throughout their range, from poaching to competition with humans for space and for food. 

Consequently, many tiger populations have become smaller and more fragmented, making them much more susceptible to diseases such as CDV. While we must continue to focus on the primary threats of poaching and habitat destruction, we now must also be prepared to deal with the appearance of such diseases in the future."

Priorities for future research, according to the authors, include identifying the domestic and wild carnivore species that contribute to the CDV reservoir, and those that are the most likely sources of infection for tigers. Tigers are too rare to sustain the virus in the long term, so CDV must rely on more abundant carnivore species to persist in the environment. 

Understanding the structure of the CDV reservoir will be a critical first step in identifying measures that might prevent or control future outbreaks. In addition, since we now know that small tiger populations are at greater risk to diseases such as CDV than larger populations, conservation strategies focusing on connectedness between populations become all the more important. "Estimating the potential impact of canine distemper virus on the Amur tiger population (Panthera tigris altaica) in Russia," appears in the current online edition of PloSONE. Authors include: Martin Gilbert of WCS and Boyd Orr Centre for Population and Ecosystem Health at the University of Glasgow; Dale G. Miquelle of WCS; John M. Goodrich of Panthera; Richard Reeve, Sarah Cleaveland and Louise Matthews of Boyd Orr Centre for Population and Ecosystem Health at the University of Glasgow; and Damien Joly of WCS and Metabiota.

This study was made possible through generous support from Morris Animal Foundation, Zoo Boise Conservation Fund, AZA Tiger Species Survival Plan Tiger Conservation Campaign, and the Biotechnology and Biological Sciences Research Council.

"Morris Animal Foundation is thankful to Dr. Miquelle and his team for helping protect the Amur Tigers," said Diane Brown, DVM, PhD, DACVP and Chief Scientific Officer for Morris Animal Foundation. "Our Foundation values their hard work and dedication to this study and we look forward to many more partnerships with the Wildlife Conservation Society."

Source: Wildlife Conservation Society

Camera trap images help wildlife managers ID problem tigers in India

Researchers with WCS and other partners in India are camera traps to ID individual tigers in conflict and relocate them out of harm's way for the benefit of both tigers and people. Credit: WCS

Researchers with the Wildlife Conservation Society and other partners in India are using high-tech solutions to zero in on individual tigers in conflict and relocate them out of harm's way for the benefit of both tigers and people.

In recent tiger-conflict cases involving both a human fatality and the predation of livestock, both occurring near two of India's national parks, WCS scientists helped to identify problem tigers using stripe pattern-matching software and additional information to make the connections. Both tigers have been captured and relocated to a nearby zoo.

Reducing human-wildlife conflict while promoting human welfare and conservation in important wildlife habitats is one of many topics under discussion of the World Parks Congress, a once-in-a-decade event focusing on the management and expansion of the world's protected area networks and the wildlife they contain. The congress, which took place in Sydney, Australia concluded today.

A new paper titled "Photographic Database Informs Management of Conflict Tigers" appears in the latest version of the journal Oryx. The authors are: Ullas Karanth, N. Samba Kumar, and Divya Vasudev of WCS's India Program.

"The vast majority of tigers generally avoid humans and focus only on natural prey species," said Dr. Ullas Karanth, WCS's Director for Science-Asia and lead author on the paper. 

"Using scientific methods to locate individuals involved in conflict with humans and livestock helps us to mitigate threats to people and prevent the capture of the wrong tigers, especially wherever tigers may venture beyond protected area borders."

While tigers struggle to survive in other landscapes across their range through Asia, the big cats in the Malenad Tiger Landscape of southwest India have thrived, becoming one of the largest tiger populations in the world with an estimated 400 animals.

Part of this conservation success has been due to a WCS research program focused on the identification of individual tigers. The system uses unique stripe patterns to identify and track individual animals, and software programs have greatly improved the speed and accuracy of the process. Since the initiation of the research protocol, more than 750 tigers have been identified from six protected areas in the Malanad Tiger Landscape in the Western Ghats across India. The system also enables researchers to keep track of other data such as home range locations, age and ex of individual animals, activity patterns. Over the longer term it even enables estimation of survival and recruitment rates and changes in numbers, all of which can be used to inform management decisions on wild tigers.

The tiger database has become a key factor in finding and capturing problem tigers. One of the recently captured animals was involved in the loss of human life near Bandipur National Park in late December of 2013. Scientists managed to get pictures of the animal from camera traps set up near the area of conflict and discovered a match with an animal photographed over a 5-year period and probably past its prime. Old tigers unable to catch natural prey animals can sometimes resort to hunting livestock, bringing them in conflict with people.

Another tiger, involved in the killing of cattle in a village next to Nagarahole National Park, was by contrast a 2-3 year old youngster some 35 kilometers from locations in which it was previously photographed. Scientists concluded this young tiger was likely searching for a territory, beyond protected areas.

Once ranging across Asia from Turkey to Indonesia, the tiger has been decimated by a combination of habitat destruction, overhunting of prey animal, poaching for the illegal trade and retaliatory killing by humans. The total wild population has been reduced in numbers from perhaps 100,000 at the turn of the 20th Century to a current estimate of fewer than 3,500 animals remaining in only 6 percent of the species' historic range.

Source: Wildlife Conservation Society

A New, tighter timeline confirms ancient volcanism aligned with dinosaurs' extinction

A definitive geological timeline from Princeton University researchers shows that a series of massive eruptions 66 million years ago in a primeval volcanic range in western India known as the Deccan Traps played a role in the extinction event that claimed Earth's non-avian dinosaurs, and challenges the dominant theory that a meteorite impact was the sole cause of the extinction. Pictured above are the Deccan Traps near Mahabaleshwar, India.
Credit: Image courtesy of Gerta Keller, Department of Geosciences

A definitive geological timeline shows that a series of massive volcanic explosions 66 million years ago spewed enormous amounts of climate-altering gases into the atmosphere immediately before and during the extinction event that claimed Earth's non-avian dinosaurs, according to new research from Princeton University.

A primeval volcanic range in western India known as the Deccan Traps, which were once three times larger than France, began its main phase of eruptions roughly 250,000 years before the Cretaceous-Paleogene, or K-Pg, extinction event, the researchers report in the journal Science. For the next 750,000 years, the volcanoes unleashed more than 1.1 million cubic kilometers (264,000 cubic miles) of lava. The main phase of eruptions comprised about 80-90 percent of the total volume of the Deccan Traps' lava flow and followed a substantially weaker first phase that began about 1 million years earlier.

The results support the idea that the Deccan Traps played a role in the K-Pg extinction, and challenge the dominant theory that a meteorite impact near present-day Chicxulub, Mexico, was the sole cause of the extinction. The researchers suggest that the Deccan Traps eruptions and the Chicxulub impact need to be considered together when studying and modeling the K-Pg extinction event.

The Deccan Traps' part in the K-Pg extinction is consistent with the rest of Earth history, explained lead author Blair Schoene, a Princeton assistant professor of geosciences who specializes in geochronology. Four of the five largest extinction events in the last 500 million years coincided with large volcanic eruptions similar to the Deccan Traps. The K-Pg extinction is the only one that coincides with an asteroid impact, he said.

"The precedent is there in Earth history that significant climate change and biotic turnover can result from massive volcanic eruptions, and therefore the effect of the Deccan Traps on late-Cretaceous ecosystems should be considered," Schoene said.

The researchers used a precise rock-dating technique to narrow significantly the timeline for the start of the main eruption, which until now was only known to have occurred within 1 million years of the K-Pg extinction, Schoene said. The Princeton group will return to India in January to collect more samples with the purpose of further constraining eruption rates during the 750,000-year volcanic episode.

Schoene and his co-authors gauged the age of petrified lava flows known as basalt by comparing the existing ratio of uranium to lead given the known rate at which uranium decays over time. The uranium and lead were found in tiny grains -- less than a half-millimeter in size -- of the mineral zircon. Zircon is widely considered Earth's best "time capsule" because it contains a lot of uranium and no lead when it crystallizes, but it is scarce in basalts that cooled quickly. The researchers took the unusual approach of looking for zircon in volcanic ash that had been trapped between lava flows, as well as within thick basalt flows where lava would have cooled more slowly.

The zircon dated from these layers showed that 80-90 percent of the Deccan Traps eruptions occurred in less than a million years, and began very shortly -- in geological terms -- before the K-Pg extinction. To produce useful models for events such as the K-Pg extinction, scientists want to know the sequence of events to within tens of thousands of years or better, not millions, Schoene said. Margins of millions of years are akin to "a history book with events that have no dates and are not written in chronological order," he said.
"We need to know which events happened first and how long before other events, such as when did the Deccan eruptions happen in relation to the K-Pg extinction," Schoene said. "We're now able to place a higher resolution timeframe on these eruptions and are one step closer to finding out what the individual effects of the Deccan Traps eruptions were relative to the Chicxulub meteorite."

Vincent Courtillot, a geophysicist and professor at Paris University Diderot, said that the paper is important and "provides a significant improvement on the absolute dating of the Deccan Traps." Courtillot, who is familiar with the Princeton work but had no role in it, led a team that reported in the Journal of Geophysical Research in 2009 that Deccan volcanism occurred in three phases, the second and largest of which coincides with the K-Pg mass extinction. Numerous other papers from his research groups are considered essential to the development of the Deccan Traps hypothesis. (The Princeton researchers also plan to test the three-phases hypothesis, Schoene said. Their data already suggests that the second and third phase might be a single period of eruptions bridged by smaller, "pulse" eruptions, he said.)

The latest work builds on the long-time work by co-author Gerta Keller, a Princeton professor of geosciences, to establish the Deccan Traps as a main cause of the K-Pg extinction. Virginia Tech geologist Dewey McLean first championed the theory 30 years ago and Keller has since become a prominent voice among a large group of scientists who advocate the idea. In 2011, Keller published two papers that together proposed a one-two punch of Deccan volcanism and meteorite strikes that ended life for more than half of Earth's plants and animals.

Existing models of the environmental effects of the Deccan eruptions used timelines two to three times longer than what the researchers found, which underestimated the eruptions' ecological fallout, Keller explained. The amount of carbon dioxide and sulfur dioxide the volcanoes poured out would have produced, respectively, a long-term warming and short-term cooling of the oceans and land, and resulted in highly acidic bodies of water, she said.
Because these gases dissipate somewhat quickly, however, a timeline of millions of years understates the volcanoes' environmental repercussions, while a timeframe of hundreds of thousands of years -- particularly if the eruptions never truly stopped -- provides a stronger correlation. The new work confirms past work by placing the largest Deccan eruptions nearer the K-Pg extinction, but shows a much shorter time frame of just 250,000 years, Keller said.

"These results have significantly strengthened the case for volcanism as the primary cause for the mass extinction, as well as for the observed rapid climate changes and ocean acidification," Keller said.

"The Deccan Traps mass extinction hypothesis has already enjoyed wide acceptance based on our earlier work and a number of studies have independently confirmed the global effects of Deccan volcanism just prior to the mass extinction," she said. "The current results will go a long way to strengthen the earlier results as well as further challenge the dominance of the Chicxulub hypothesis."

Source:  Princeton University