May 2011

Field & Berry Groups

May 2: Jennifer Johnson talked about a project she’s been working on for the last year related to modeling nitrogen isotope fractionation. She explained how the nitrogen (N) isotope ratio of a particular plant depends (1) on the N source (organic vs inorganic) and (2) fractionation uptake, metabolism, exchange with the atmosphere, & photorespiration. Her project is to sort out these various pathways in order to devise realistic models.
Tasting: Jen continued her mission to tout the delectability of native, wild plants by creating a delicious salad of miner's lettuce, dandelion & mint leaves toped with toyon berries (also called Christmas berry) and avocado & lemon juice dressing. The berries were a pleasant surprise.
May 9: Rebecca Hernandez covered her previous research on biological soil crusts (BSC) and why they matter. In arid or semi-arid lands, this thin crustal layer is composed initially of cyanobacteria colonies which can be invaded first by bryophytes and later by higher plants. Becca's study showed that BSC favor the growth of native plants, but if destroyed or disturbed, exotic non-natives may get the upper hand. Because approx. one-third of the earth's land surface is arid, this complex ecosystem deserves further study.
Tasting: Becca brought delicious watercress, cream-cheese sandwiches and apple slices. She purchased the watercress at Whole Foods Market and hoped it was a native variety because that which one may find in local streams is likely to be contaminated with pathogens.
May 16: Robert Heilmayer & Steve Klosterman are PhD students beginning their dissertation research. Today, Robert described his on-going studies of the Drives & Impacts of Chilean Forest Transitions. He gave us a broad description of both the native forests and tree plantations in different parts of Chili. The latter are composed mostly of fast-growing eucalyptus and monterey pine which are harvested frequently for wood export. And he hopes to learn what are the drivers for the regrowth of native forests.
Tasting: Steve tossed the organic ingredients for a unique & delicious carrot salad. Besides several varieties of carrots, it contained cilantro, cumin and a lemon juice & oil dressing plus raisins to add on the side.
May 27: Matt Colgan brought us up to date on his dissertation research based in Kruger Nat'l Park, South Africa. He called it "Climate, landscape, and disturbance controls over savanna woody plant biomass using airborne remote sensing." Using a transect just outside the Park that's part of a mining operation allows him to cut some trees and otherwise disturb the landscape. He's comparing the plants growing in basaltic soils with those in granite soil. The former provides more nitrogen and other minerals and thus more growth.
Tasting: Kelly McManus brought two home-baked, deep-dish pizzas containing several native plants including fennel, miner's lettuce & mint. Delicious!!

News from Jasper Ridge

May 2: The current Spring Harvest at the Jasper Ridge Global Change Experiment (JRGCE) began under the supervision of Todd Tobeck who reported: "There are currently four of us full time and several part timers working on harvest this time of year. Bill Gomez is a docent who has been donating time every year for as long as I have been on the project, a real trooper. Please give him honorable mention for his continued work on our project." Todd also said that digging the cores to measure root growth & carbon storage is harder this year - perhaps because of the unusually wet Spring.
The May 10 issue of the Stanford Report online featured an article with the title: Stanford faculty committee appointed to study Searsville Dam, Reservoir. This Committee includes Chris Field and is to develop a Habitat Conservation Plan (HCP) to establish a conservation strategy for the next 50 years. Information about the Plan can be found at HCP Highlights Brochure (PDF, 580 KB)


Jan Brown, Editor, Email:
Click on Photos to Enlarge


Kelly picks a raffle winner.










Seminar Speakers

May 3: Prof. Allen Goldstein, Dept of Environmental Science, Policy, and Management & Department of Civil and Environmental Engineering, Univ. California, Berkeley. spoke about Known and Unexplored Organic Constituents in the Earth’s Atmosphere. He talked mainly about biogenic aerosols that are produced by trees (e.g. terpenes) which are 10X greater than those produced anthropogenically. They also react together but most of the carbon in aerosols is biogenic.

May 10: Dr. Anna Sala, Professor, Division Biological Sciences, Univ. Montana, spoke to the title: The carbon-balance approach to tree growth and survival: helpful or misleading? She discussed the limitations which trees & shrubs have for carbon storage, one of which is height. Go to her Website for more info. <>

May 26: Jason Keller, Earth & Environmental Sciences, Chapman Univ. spoke to the title — Humic substances as key regulators of decomposition in wetland ecosystems. He has been measuring the amounts of stored carbon and methane as well as the ratio of CO2/CH4 in different peats and bogs. The results show a peatland gradient with this ratio being the greatest in bogs.


DGE In House Seminars

April 25: The DGE internal 45-minute dual seminar series started with Ken Caldeira giving us an overview of his Lab's activities. Mike Mastrandrea was the second speaker talking about what he and Kate Mach are doing with the IPCC. Jen Johnson has kindly volunteered to help coordinate speakers for this series which are planned to occur every two weeks and include all students & post-docs.
May 9: Bill Anderegg summarized his current research on Widespread forest die-off. Mainly he is working on Sudden Aspen Decline (SAD) to try to determine how climate change may affect it and similar forest species. Julia Pongratz followed with a discussion of Land use and climate - from Genghis Khan to geoengineering. She has been analyzing how humans influencing land-use as well as the Industrial Revolution have all contributed to global climate change. Other topics such as geoengineering and extreme events were also mentioned.
May 23: Rumi Asano described her work as both Lab and IT Manager for DPB & DGE. For computer related problems at DGE, she is aided by Rob & Patrick. Chris Field then filled us in on the latest results from Global Change Experiments at Jasper Ridge. These grasslands serve as an excellent model system in part because they sit on earthquake fault lines with various micro climates and soil types. The harvest this past month yielded some unusual results in that two species of thistle dominated the plots and their growth was greatly stimulated by both CO2 & nitrogen.

May 27: Becca Hernandez & Kelly McManus organized The 1st Annual DGE Women's Luncheon 2011, TO FOSTER SOLIDARITY AND SUPPORT, WELCOMES STAFF, FACULTY, AND STUDENTS OF THE DGE 12:00 to 1:30 p.m. WITH A SPECIAL ADDRESS (short talks) BY Nona Chiariello and Jan Brown, AND SPONSORED BY Starbucks & California Pizza Kitchen WITH DOOR PRIZES INCLUDING GIFT CERTIFICATES TO FRAICHE FROZEN YOGURT, BE YOGA, and THE CHEESECAKE FACTORY, Location:  Plant Bio Seminar Room, Food and Beverages Provided. All are welcome!
This info had been distributed as an email flyer, and about a dozen women came to enjoy the food (on decorated tables) and conversation. Jan described some of her experiences working as a woman scientist (part time) when she joined the much smaller DPB about 50 years ago. Nona followed by noting the many improvements in the working conditions of women in science both at Stanford & Carnegie since then. Nona also gave us a most welcome introductory bio of Anna Michalak who arrives next month to be our first DGE woman faculty member. Let’s hope this type of get-together becomes a tradition. Any volunteers?