Fungi Regulate Rainforest Diversity

January 2014

Fungi Regulate Rainforest Diversity 

Link: http://www.sciencedaily.com/releases/2014/01/140122133827.htm

     Oxford University led research that found that fungi control diversity in rainforests by making dominant species victims of their own success. Fungi spread quickly between tightly bunched plants of the same species, preventing them from dominating and allowing a wider range of species to thrive.

     Dr. Owen Lewis of Oxford University's Department of Zoology, the man who led the study, reported, "Seedlings growing near plants of the same species are more likely to die and we now know why. It has long been suspected that something in the soil is responsible, and we've now shown that fungi play a crucial role. It's astonishing to see microscopic fungi having such a profound effect on entire rainforests. Fungi prevent any single species from dominating rainforests as they spread more easily between plants and seedlings of the same species. If lots of plants from one species grow in the same place, fungi quickly cut their population down to size, leveling the playing field to give rarer species a fighting chance. Plots sprayed with fungicide soon become dominated by a few species at the expense of many others, leading to a marked drop in diversity."

     The study looked at seedling plots across 36 sampling stations in the Chiquibul Forest Reserve, Belize, and was published in Nature. It was carried out by scientists at Oxford University and Sheffield University and funded by the Natural Environment Research Council (NERC).

     Every week for 17 months, researchers sprayed plots with water, insecticide, or fungicide. They found that the fungicide 'Amistar' hindered diversity, reducing the effective number of species by 16%. Although the insecticide changed the arrangement of surviving species, it did not have an overall impact on diversity.

     Scientists believed that fungus-like microorganisms called oomycetes may also play a part in regulating rainforest diversity, but after the study, this theory proves to be unlikely. "Oomycetes are potent pathogens that can cause seeds and seedlings to rot, and were responsible for the 1840s potato famine," said Professor Sarah Gurr, formerly of Oxford University.

     The findings show that fungi play a vital role in maintaining the biodiversity of rainforests, preventing a few highly competitive species from dominating. This helps explain why tropical rainforests are more diverse than forests in temperate countries.

Drug trafficking leads to deforestation in Central America

January 2014

"Drug trafficking leads to deforestation in Central America"

Link: http://www.sciencedaily.com/releases/2014/01/140130141217.htm

     An article in the journal Science describes seven researchers who worked in Central America on growing evidence that drug trafficking threatens forests in remote areas of Honduras, Guatemala, Nicaragua and nearby countries. These traffickers are slashing down forests, usually within protected areas, in order to make way for secret landing strips and roads to move drugs. Additionally, they are converting forests into agribusinesses to launder their drug profits. Kendra McSweeney, the lead author of the Science article and an associate professor of geography at The Ohio State University, says that this trafficking is a response to U.S.-led anti-trafficking efforts, especially in Mexico.

     The researchers found that the amount of new deforestation per year more than quadrupled in Honduras between 2007 and 2011, the same period when cocaine movements in the country also spiked. In the Science article, McSweeney and her co-authors write that deforestation starts with the covert roads and landing strips that traffickers create in the remote forests. The mixing of drug cash into these areas helps encourage resident ranchers, land speculators and timber traffickers to move forward with their efforts, even at the expense of the indigenous people who are often important forest protectors.

     The drug traffickers also convert the forest areas to agriculture as a way to launder their money. Although this land conversion occurs within protected areas and is therefore illegal, drug traffickers use their profits to sway government leaders to their side.

"McSweeney said more research is needed to examine the links between drug trafficking and conservation issues. But there is already enough evidence to show that U.S. drug policy has a much wider effect than is often realized."

Food Production in Africa Limited Due to Fertilizer Imbalance

January 2014

Fertilizer nutrient imbalance to limit food production in Africa

Link: http://www.sciencedaily.com/releases/2014/01/140128094718.htm

            According to a new study published in the journal Global Change Biology, an increasing inequity between phosphorus and nitrogen fertilizer use in Africa may result in crop yield reductions of nearly 30% by 2050. The underuse of phosphorus - based fertilizers in Africa currently contributes to this growing yield gap. The phosphorus - specific yield gap currently lies at around 10% for subsistence farmers, but will grow to 27% by 2050 if the recent trends continue.

            "As farmers use fertilizers for their crops, nutrients such as nitrogen and phosphorus build up in the soil, providing a reserve of nutrients that plants need to grow." Although this is true, fertilizer use in Africa remains very low, and in order to increase crop production, farmers must increase their fertilizer use. Though nitrogen-based fertilizer usage has started to increase in Africa in the last 10 years, the application of phosphorus to cropland has increased at the same rate, producing a "growing imbalance" between nitrogen and phosphorus levels in the soil.

            The study used data from Food and Agriculture Organization (FAO) crop trials along with a recognized EPIC large-scale crop model to approximate how the imbalance affects present and future crop yields.

Caterpillars Adapting to Climate Change

December 2013

Caterpillars Adapting to Climate Change

Link: http://www.sciencedaily.com/releases/2013/12/131219093558.htm

      In Colorado and California, two species of caterpillars have evolved to feed quickly at higher temperatures and at a wider range of temperatures over the past 40 years, suggesting that they are evolving rapidly to survive a hotter, more variable climate.

     Joel Kingsolver at UNC-Chapel Hill began work that represents an unusual instance of how recent climate change affects physiological traits, such as how the body regulates feeding behavior. Jessica Higgins, a graduate student in Kingsolver's lab led the study, working with fellow graduate student Heidi MacLean, Lauren Buckley, and Kingsolver to compare modern caterpillars to their ancestors from 40 years ago.

     Kingsolver said that this is so far the first instance that has shown changes in physiological traits in response to climate change. He also explains that Caterpillars can eat and grow only when it's not too cold and not too hot, but when temperatures are so ideal, caterpillars eat in unrestrained manner and can gain up to 20 percent of their body weight in an hour. That growth determines their ability to survive, how quickly they become adult butterflies, and their eventual reproductive success.

     Results show that the two related species of Colias (sulphur) butterflies have adapted in two ways. First, they extended the range of their ideal feeding temperatures. Second, they shifted their optimal feeding temperature to one that is higher.

     The researchers measured changes in climate at the two study sites and then examined changes in how fast caterpillars ate using current and historical data from the 1970s. Even though little change in the average air temperature at both study sites was discovered, it was noticed that the frequency of hot temperatures (exceed 82 degrees Fahrenheit) increased two-fold in Colorado and four-fold in California over the past 40 years. In response to these temperature fluctuations, today’s caterpillars in Colorado ate faster at higher temperatures than their 1970s counterparts. In California, the modern caterpillars ate faster at both high and low temperatures, but their optimal feeding temperatures did not change.

Lower Rio Grande Basin Water Supply

December 2013

Lower Rio Grande Basin Water Supply

Link: http://www.sciencedaily.com/releases/2013/12/131217171000.htm

     “Bureau of Reclamation Commissioner Michael L. Connor released the Lower Rio Grande Basin Study that evaluated the impacts of climate change on water demand and supply imbalances along the Rio Grande along the United States/Mexico border from Fort Quitman, Tex., to the Gulf of Mexico.”

     According to Commissioner Connor, this study will provide water managers with science-based tools to make important future decisions as they work to meet the region's diverse water needs. It will also help update water management discussions between the U.S. and Mexico through the International Boundary Water Commission.

     The study concludes that climate change is likely to result in increased temperatures, decreased precipitation and increased evapotranspiration. “As a result of climate change, a projected 86,438 acre-feet of water per year will need to be added to the 592,084 acre-feet per year of supply shortfall predicted in the existing regional planning process in 2060, for a total shortfall of 678,522.”

     Water supply disparities made worse by climate change will significantly reduce the dependability of distributions to all who are dependent on the Rio Grande’s water via irrigation deliveries.

     Seawater desalination, brackish groundwater desalination, reuse and fresh groundwater development were studied as alternatives to meet the future water demands. It was found that the brackish groundwater development was most suitable. “Next, an appraisal-level plan formulation and evaluation process was conducted to determine potential locations of each regional brackish groundwater desalination system.”

     The Lower Rio Grande Basin Study was established by Reclamation and the Rio Grande Regional Water Authority and its 53 member individuals. It was directed in association with the Texas Region M Planning Group, Texas Water Development Board, Texas Commission on Environmental Quality and International Boundary and Water Commission. It covered a total pf 122,400 square miles and cost $412,798 with the RGWRA paying for 52%.

Solar Activity and Climate Change

December 2013

Solar Activity and Climate Change

Link: http://www.sciencedaily.com/releases/2013/12/131222161813.htm

     A new scientific study shows the climate change has not been strongly influenced by variations in heat from the sun contrary to popular belief. This new discovery discounts the thought that lengthy periods of warm and cold weather in the past might have been caused by intermittent fluctuations in solar activity.

     Research investigating the causes of climate change in the northern hemisphere over the past 1000 years has shown that until the year 1800, the leader of periodic changes in climate was volcanic eruptions. Volcanic eruptions have a tendency to prevent sunlight from reaching Earth, causing cool, drier weather. But since 1900, greenhouse gases have been the primary cause of climate change. These findings prove that periods of low sun activity should not be expected to have a large impact on temperatures on Earth and should additionally help climate forecasting.

     

Scientists at the University of Edinburgh continued the study using records of past temperatures. They compared this data record with computer-based models of past climate, highlighting all changes in the sun. “They found that their model of weak changes in the sun gave the best correlation with temperature records, indicating that solar activity has had a minimal impact on temperature in the past millennium.”

How to Save Fiji's Coral Reefs

December 2013

How to Save Fiji's Coral Reefs

Link: http://www.sciencedaily.com/releases/2013/12/131217155329.htm

     “Thinking about the connections between the land and sea is rarely done when designing protected areas – Fiji is leading the way globally," said Dr. Carissa Klein, one of the many authors of the online edition of Marine Policy.

     Although many "managers" realize how downstream ecosystems such as coral reefs can be negatively affected by land-based activities, there have been few ‘on-the-ground’ cases where protected area networks have been designed using integrated planning to minimize external threats that cause increases in runoff and associated sediments, nutrients, and chemicals.

     The small island and developing state Fiji is just one example where selection of the locations of terrestrial protected areas have been based more on the cultural or timber value of forests than on protecting biodiversity. Fiji's current terrestrial protected areas cover less than 3 percent of land area in the country. However, these protected areas do not protect Fiji's sensitive island habitats and species or help minimize runoff to adjacent coral reefs.

     In 2008, a national Protected Area Committee was created by the Fiji government to achieve the goals of protecting 20 percent of the country's land and 30 percent of its coastal waters by the year 2020. The study authors contributed by systematically analyzing six scenarios for expanding Fiji's network of terrestrial protected area networks, with the aim to expose how well each approach would protect different forest types and minimize land-based runoff to downstream coral reefs. The study authors also recommended that some additional forests be added to their national register of priority places for protection.

     The committee took this advice and added additional forest areas to the final register of priority places for management endorsed by the Fiji government National Environment Council in October 2013.

     Dr. Caleb McClennen, director of the WCS Marine Program stated, "Their decision to take action and link land to sea conservation helps to ensure the long term security of their globally important coral reef ecosystems while supporting the livelihoods and resilience of coastal communities."