Posts Tagged: Water
I have the privilege of engaging California's communities with the aspiration of safeguarding the sustenance and well-being that its oak-woodland watersheds and the people that are a part of them provide. This millennia-long integrated relationship of humans and land has parallel histories in other Mediterranean parts of the world. The following blog is the first of occasional installments about working Mediterranean landscapes in California and around the globe. Combined they will explore the concepts of watershed functions, working landscapes and Mediterranean climate, vegetation and management. Join me in experiencing these settings, growing our appreciation for the integrated nature of these landscapes and people, and gaining understanding and tools for our tenure as stewards. - David Lewis, director, UC Cooperative Extension, Marin County
I am standing where stream flow begins, in a nameless tributary of the Russian River to the east of Hopland, Calif. This particular spot and location has been a grazing livestock ranch, primarily sheep, going back more than 100 years (learn more). This is one of thousands of spots in a watershed where water comes to the surface, joins in a channel and starts its path downstream. Many of us have stood at a confluence of two rivers or an estuary where a watershed's outfall meets an ocean. These locations are the stream's or river's end, their terminus. Where I am standing, is the headwaters of a stream system, where water is initially released and visible as a thin, shallow bouncing band.
Watersheds collect, store, and transport water. The transport function is performed by streams and rivers. These are dynamic, pervious channel networks each with a beginning and an end. At any part of the network, the channel is that lowest point in the landscape, stretching from one stream bank to the other, and generally widening in the downstream direction, until the stream mouth empties into another water body.
At the other end of a network is the channel head, where the channel begins. This is where I am standing. Channel heads are found in small, intimate folds in the landscape. These depressions are referred to by many names — draws, bowls, hollows — the place in hills where the slopes become shallow and coalesce.
Like an amphitheater, the surrounding hillslopes rise around me. Reaching out at shoulder height, I can almost touch these slopes. The mixed oak woodland and interspersed grasslands are in attendance across these slopes. Ghost pines, live oaks, black oaks and madrones, among other trees, make their stand interspersed with annual and perennial grasses blanketing the ground. This mosaic of vegetation is hosted and sustained by the complex mix of marine sediments that have been pushed up, forming these hills, and erosion carving the stream channel. Below the surface are soils one to three feet deep that have developed from the underlying geology.
It's March 3, 2019, and on the cusp of spring. Between the light breezes, the stream water sings its way downstream. I think back to the intense storms that moved across this part of California the week before and the resulting floods in the lower portion of the Russian River. Those and earlier winter storms soaked into the soil until the soil reached its capacity to hold water. Once the soils were primed, water was released to the channel network. That water is still being released now, days later, and will be for several more months into May or even June. Rainfall for this area and most of California has been substantial, matching amounts not seen since 1983, and definitively ending the nearly five-year drought. This contrast in extremes is the norm for California, meaning the next drought or next flood is only a year away.
Downstream the Russian River is perennial, flowing year-round. But here at the channel head, flow is intermittent on an annual cycle. Rains begin in the fall, with headwater surface flows starting in late fall or early winter, once soils are saturated. This wetting up process reverses in the spring, until the channel head is dry.
At some point this year flow in the headwaters will stop. Saturated soils releasing water laterally below the ground surface, will gradually release less and less water to the channel. Trees and grasses will demand more and more water as they leaf out and grow. As soils pores empty of free water, the remaining moisture is held more tightly to soil particles and plant root surfaces through a physical tension. Eventually the channel head will run dry.
While you may not have the opportunity to visit a channel head and experience the place where stream flow starts and stops each year, you are often closer to one than you think. Driving a rural road or hiking in a favorite park or open space will invariably find you crossing one of these unnamed headwater streams. As you do, give a look upstream, from where the water going past you has come. Up the channel into the bowl is one of the channel heads and headwaters for the watershed you are in.
I don't know when I will get to this channel head again. However, this place where surface flow is initiated will be close in my mind, particularly, as I visit the confluences and estuary of the Russian River, during the wet and dry periods and high and low rainfall years to come.
To learn more about these specific watersheds and research conducted in them this article is suggested. If interested in learning how stream flow is generated in California oak woodland watersheds you may want to read this article./span>/span>
Pledging to work together to solve water scarcity issues, Israel's Agricultural Research Organization signed a memorandum of understanding with UC Division of Agriculture and Natural Resources and UC Davis on July 16. The signing ceremony kicked off the 2018 Future of Water for Irrigation in California and Israel Workshop at the UC ANR building in Davis.
“Israel and California agriculture face similar challenges, including drought and climate change,” said Doug Parker, director of UC ANR's California Institute for Water Resources. “In the memorandum of understanding, Israel's Agricultural Research Organization, UC Davis and UC ANR pledge to work together more on research involving water, irrigation, technology and related topics that are important to both water-deficit countries.”
The agreement will enhance collaboration on research and extension for natural resources management in agriculture, with an emphasis on soil, irrigation and water resources, horticulture, food security and food safety.
“It's a huge pleasure for us to sign an MOU with the world leaders in agricultural research like UC Davis and UC ANR,” said Eli Feinerman, director of Agricultural Research Organization of Israel. “When good people, smart people collaborate the sky is the limit.”
Feinerman, Mark Bell, UC ANR vice provost, and Ermias Kebreab, UC Davis professor and associate vice provost of academic programs and global affairs, represented their respective institutions for the signing. Karen Ross, California Department of Food and Agriculture secretary, and Shlomi Kofman, Israel's consul general to the Pacific Northwest, joined in celebrating the partnership.
“The important thing is to keep working together and develop additional frameworks that can bring the people of California and Israel together as researchers,” Kofman said. “But also to work together to make the world a better place.”
Ross said, “It's so important for us to find ways and create forums to work together because water is the issue in this century and will continue to be.”
She noted that earlier this year the World Bank and United Nations reported that 40 percent of the world population is living with water scarcity. “Over 700,000 people are at risk of relocation due to water scarcity,” Ross said. “We're already seeing the refugee issues that are starting to happen because of drought, food insecurity and the lack of water.”
Ross touted the progress stemming from CDFA's Healthy Soils Program to promote healthy soils on California's farmlands and ranchlands and SWEEP, the State Water Efficiency and Enhancement Program, which has provided California farmers $62.7 million in grants for irrigation systems that reduce greenhouse gases and save water on agricultural operations.
“We need the answers of best practices that come from academia, through demonstration projects so that our farmers know what will really work,” Ross said.
As Parker opened the water workshop, sponsored by the U.S./Israel Binational Agricultural Research and Development (BARD) Program, Israel Agricultural Research Organization and UC ANR, he told the scientists, “The goal of this workshop is really to be creating new partnerships, meeting new people, networking, and finding ways to work together in California with Israel, in Israel, with other parts of the world as well.”
Drawing on current events, Bell told the attendees, “If you look at the World Cup, it's about effort, it's about teamwork, it's about diversity of skills, and I think that's what this event does. It brings together those things.”
Not more than three months on the job and Konrad Mathesius is hard at work bringing farmers together to discuss the unique challenges that Sacramento Valley farmers face. As the new UCCE agronomy advisor for Sacramento, Solano and Yolo counties, his role is designed specifically to help growers with their crop issues – pests, disease and fertility – but with a strong background in soil science, Mathesius hopes to shed light on the diversity of soils in the region and the unique management considerations that each necessitates.
In hopes of highlighting this diversity of soils and encouraging growers to dig a little deeper to better inform their management practices, Konrad enlisted the help of UCCE soil resource specialist Toby O'Geen to lead a field tour of three major soils in the southern Sacramento Valley. The event included three pit stops on two Yolo County farms and brought out a diversity of participants from USDA Natural Resources Conservation Service agents, to resource conservationists, to farmers and crop advisors.
Kicking things off at Rominger Brother's Ranch -- a diversified family farm in Winters that grows everything from wine grapes to processing tomatoes to rice, wheat, corn, onions, alfalfa and hay -- O'Geen took the audience on a journey back in time, describing the rich natural history of the former floodplain that has given rise to the rich, productive soils that support California agriculture today. After introducing himself as a pedologist, or a scientist who studies the nature and properties of soil, he went on to introduce the five soil forming factors and their role in molding initial (1) parent material (i.e. rocks), under the influence of (2) climate, (3) topography and (4) organisms and over a given period of (5) time into soils.
Proving that soil scientists take the term “pit stop” literally, Mathesius shifted the conversation to a 1.5-meter deep hole in the ground, dug out the day before with a back hoe. Step by step, he walked participants through the process of analyzing a soil pit – cleaning the face, identifying horizons or individual layers and using the senses to assess soil properties and determine function. As he struck the face of the pit with a rock hammer, an audible difference was detected between the surface layers and the subsurface.
Working backwards from the sound, he explained that the subsurface was significantly harder, which he attributed to a finer texture and ultimately identified as a clay pan, a restrictive layer that prevents roots from penetrating deeply and has the capacity to waterlog soils, due to poor drainage. O'Geen offered some tangible advice as to how to manage these soils, quipping that a deep rip would be no better than cutting butter with a knife (eventually it all just settles back into place) while likening a slip plow to a giant shank that just inverts the soil, mixing things to about a depth of 6 feet and permanently eliminating the problem.
From there, Mathesius segued into a hands-on exercise to determine the soil texture, or percent distribution of various size particles, allowing participants to work on their pottery skills making balls and ribbons with the clay-rich soils. Discussing the many functions that soil texture controls, led the conversation down a rabbit-hole around water holding capacity and how to calculate the range of plant available water for your soil.
With the demos out of the way, they voyaged to the next pre-dug pit, bringing participants face to face with the harsh reality of soil heterogeneity. Just 300 feet away and it was as if we had ventured into another environment altogether, yet these soils formed in the same place, under the same climate and similar vegetation, but in a completely different time with slightly different starting material.
By changing just a couple of the ingredients in the special sauce of soil formation the results are completely different featuring a clay dominant surface soil and entirely different water management challenges. And these aren't just any clays, but a special class that swell and shrink as they wet and dry, oftentimes shearing roots under the pressure and creating a hospitable environment for disease to thrive. O'Geen suggested trying to keep them in the sweet spot where they are consistently moist, but not wet, and never allowed to dry out. Unfortunately, there is no precise measurement to that formula, “you just have to be almost like an artist. It's a lot of feel to it and the numbers sometimes just don't work out. It just comes with years of experience. Its one of those native intelligence things that you just have to feel your way through,” he noted.
Caravanning 20 miles back towards Davis, the tour arrived at the third and final pit, located at Triad Farms, a tomato operation in Dixon. Well-drained, young and fertile, Yolo loam soils are the poster children of agriculture, owing in large part to regular deposits of silts from past flood events. With not many management challenges to speak of, conversation immediately shifted towards an undocumented challenge that farmers on the eastern side of the Sacramento Valley are all too familiar with – the unavailability of potassium, even under intensive fertilization regimes. While the jury is still out on the cause and while it contradicts what soil scientists expect to find in those regions, possible explanations were tossed around and O'Geen used the opportunity to stress the importance of speaking up about things growers or advisors see going on in their area. Turns out the USDA-NRCS is working on updating its inventory of soil surveys, documenting soils across the nation and is currently seeking input on what's working for growers and where things are differing on the ground.
Ultimately, in closing, Mathesius called for more engagement between the university, extension and growers. O'Geen reminded everyone that “You can really learn a lot by digging a hole, looking at stuff, and developing theories. Sometimes you're wrong, but they're kind of fun to talk about."
University of California students are taking a long journey through California to trace the state's complicated and critical water supply. The recent graduates and upper-division co-eds from UC Merced, UC Santa Cruz, UC Berkeley and UC Davis are part of the UC Water Academy, a course that combines online training with a two-week field trip for first-hand knowledge about California water.
The tour began June 18 at Lake Shasta, the state's largest reservoir, and followed the water's course to the Sacramento Valley, through the Sacramento-San Joaquin Delta and south along the Delta-Mendota Canal. Since a key water destination is agriculture, the UC Water Academy toured the UC Kearney Agricultural Research and Extension June 23, where research is underway to determine how the state's water supply can be most efficiently transformed into a food supply for Americans.
“You're visiting a place ideal for growing high-quality fruits and vegetables, because of the Mediterranean climate and low insect and disease pressure,” said Jeff Dahlberg, director of the UC KREC.
UC Cooperative Extension water management specialist Khaled Bali joined the students next to his alfalfa research plot, where different irrigation regimens are compared to determine the maximum yield that can be harvested with the minimum amount of water.
“It used to be that the No. 1 objective was to maximize yield,” Bali said. “But with the limited supplies and the cost of water, now the No. 1 objective is to get the maximum economic return. Growers might be better off selling some of their water to other jurisdictions.”
A water tour wouldn't be complete without an introduction to drought research. A recently planted sorghum trial provided the backdrop.
“California is a great place to study drought tolerance,” Dahlberg said, “because you can induce a drought by withholding irrigation.”
The sizable field contains 1,800 plots with 600 sorghum cultivars under three irrigation schemes: one irrigated as usual, one in which water is cut off before the plants flower, and the final one where water is cut off after the plants flower.
“Every week, a drone flies over to collect data on the leaf area, plant height and biomass,” Dalberg said. “Hopefully we will get associations with gene expression and this phenotype data."
Dahlberg and his collaborating researchers believe identifying the genes responsible for drought tolerance in sorghum will help scientists find drought-tolerant genes in other cereal crops – such as wheat, corn, rice and millet. “This will go a long way to feeding the people of the world,” he said.
There is still much to learn about sorghum drought tolerance – is it conferred by the plant's waxy leaves, the way stomata are controlled, accumulation of sugar in the leaves, or a mechanism in the roots?
“These are all questions you will have to answer to feed the world,” Dahlberg said. “That's why I would encourage you to continue studying water. There's a lot for you to get into.”
A third-year earth science student at UC Santa Cruz and a member of the academy, Denise Payan, said the sense of responsibility for the future is not daunting, but encouraging.
“It makes me feel like I can make a difference,” she said. The tour through California is shaping her plans for the future, which may include a career at the intersection of geology and biology.
“This has opened my eyes to a lot of issues,” she said.
The next stop for the UC Water Academy is the vast Tulare Lake basin to learn about groundwater recharge before heading east to the Owens Valley and the shores of Mono Lake. From there the academy turns to the Sierra Nevada to visit San Francisco's water supply, which is collected by Hetch Hetchy Dam. The field trip ends with a two-day rafting trip on the American River.
The UC Water Academy is offered through UC Water and led by UC Merced professor Joshua Viers and UC Cooperative Extension water management specialist Ted Grantham. In addition to the two-week tour, students participated in weekly online meetings and complete a project on communicating California water issues to public stakeholders. Students receive 1 unit of academic credit.
The UC California Institute for Water Resources (CIWR) has announced the recipients of six grants to address the most critical water issues in the state. For this program, the Institute leverages funds it receives from the Water Resources Research Act of 1964 through the Department of Interior.
CIWR, which is part of UC Agriculture and Natural Resources, facilitates collaborative research and outreach on water issues across California's academic institutions and with international, federal, state, regional, nonprofit, and campus communities.
Small grants to support initial work will be dispersed to the following projects (click the headline for more information):
Suitability of alfalfa for winter groundwater recharge
Helen Dahlke, professor in the Department of Land, Air and Water Resources, UC Davis
One proposed solution for recharging overdrawn aquifers is flooding farmland during the rainy season. Optimizing agricultural groundwater banking for specific crops can be challenging. The goal of this project is to better understand how alfalfa, which is grown year-round, responds to winter flooding.
Fish habitat response to streamflow augmentation
Ted Grantham, UC Cooperative Extension specialist in the Department of Environmental Science Policy and Management, UC Berkeley
Declining water levels can degrade or eliminate fish habitat during California's summer season. Storing water off-channel during the rainy season can improve flow during the summer. The study is designed to gain a better understanding of the relationship between stream flow and habitat.
Remote sensing of turfgrass response to irrigation
Amir Haghverdi, UC Cooperative Extension specialist in the Department of Environmental Science, UC Riverside
Turfgrass is common in urban landscapes and provides valuable recreation areas and ecosystem services. This project will help determine the best irrigation strategies for common turfgrass species.
Habitat restoration impacts on water management
Eric Palkovacs, professor in the Department of Ecology and Evolutionary Biology, UC Santa Cruz
The natural conditions of the Sacramento-San Joaquin Delta have been changed by habitat alteration and non-native predacious fish introduction. This project will examine the interplay between altered habitat and predatory fish, and how they impact native salmon populations.
Evaluating water conservation policy in California
Leah Stokes, professor in the Department of Political Science, UC Santa Barbara
During the recent drought, California required that on-average urban water districts conserve 25 percent of their water. While some districts were successful, others failed to meet their target. This project will examine how variation in policy – pricing, messaging and penalties – and drought severity affected water conservation.
Groundwater dynamics after California drought
Amelia Vankeuren, professor in the Department of Geology, Sacramento State University
As part of California's groundwater management act, some basins were designated as high management priorities. This project will characterize groundwater using age, location and temperature. This information will be valuable for stakeholders creating a groundwater sustainability plan.