Study: 58 Million Trees at ‘Severe’ Risk
A new study published Monday in Proceedings of the National Academy of Sciences concludes that an estimated 58 million California forest trees are at “severe” risk due to water stress resulting from the ongoing drought.
Cumulatively, these trees cover 1 million hectares, or about 2.4 million acres. The study used aerial survey techniques, so it’s unclear how many trees are already dead.
The study was led by Gregory Asner of the Carnegie Instituttion for Science, refining work he published earlier this year, which estimated there are 120 million trees at risk. That represents about 20 percent of California’s total forest cover.
The new study is more nuanced. It estimates there are 888 million trees that show measurable water loss from 2011 to 2015. About half of these have lost 10 percent of their canopy water content.
Water losses greater than 30 percent are considered “severe,” according to the authors, and there are an estimated 58 million trees in this category.
Asner and his co-authors were careful to point out that these numbers do not indicate dead trees – yet.
“Although we emphasize that these statistics do not represent mortality,” the authors wrote, “they do point to rapid increases in the vulnerability of millions of trees that were physically and physiologically affected by drought and related factors.”
Nevertheless, many of these trees face a high risk of death, representing a potentially massive alteration of habitats. If not killed by the ongoing drought, the trees face a greater risk of death by beetle infestation, high winds, snow loads, wildfire and other common environmental threats.
Trees in the southern Sierra Nevada were most at risk, as well as those on hill crests and slopes.
“I think that the new science that we’re bringing to the table here presents a significant opportunity for advancing resource management and conservation in the current time and the future of climate change,” Asner told the Washington Post. “I think that’s really what we’re after.”
Language for New Water Bond Approved
The California Secretary of State on Monday approved language for a new proposition that could appear on the November 2016 ballot authorizing the sale of $6 billion in bonds for water storage projects. The move allows supporters to begin gathering signatures to place the measure on the ballot.
The measure is backed by Jerry Meral, former deputy secretary of the California Natural Resources Agency and now water director at the Natural Heritage Institute. The proposed title for the proposition is “The Water Supply Reliability and Drought Protection Act of 2016.”
Meral now has until June 27, 2016, to collect an estimated 365,880 signatures from registered voters in order to qualify the measure for the November 2016 ballot.
The approved language, in part, states: “Authorizes $6.02 billion in general obligation bonds for water supply infrastructure projects, including watershed improvement and water quality enhancement; capturing urban runoff; water recycling and desalination; flood management; water conservation; water for wildlife; groundwater sustainability and storage; and safe drinking water.”
The primary goals are to fund stormwater systems to catch rainfall, wastewater recycling facilities and efforts aimed at desalting groundwater and brackish water, according to a recent report by the Reuters news agency.
“We believe the voters understand the very serious nature of the drought and would be willing to invest in a water bond that produces actual water to help meet their needs,” Meral said.
Others are a bit more cautious. Meral’s move comes after a $7 billion water bond was approved by voters just last year. It remains to be seen whether voters are willing to plunge the state deeper into debt for more water projects, even amid the ongoing drought.
“Bond funding alone is not going to fix the staggering ongoing costs for deferred maintenance and operations of our state and local aging and deteriorating water systems,” said state Sen. Lois Wolk (D-Davis).
For a full copy of the ballot measure proposal submitted by Meral, click here.
Top image: An aerial view of the Canyon View Campground along the San Joaquin River in the central Sierra Nevada, and an example of the tree stress and death caused by the ongoing California drought. (The Fresno Bee)