Posts Tagged: Nutrition
Las comidas universales aumentan la participación y reducen el estigma
La pandemia, con sus enormes desafíos puso en riesgo la alimentación y nutrición de los estadounidenses. Al inició de la crisis muchas familias perdieron el acceso a los alimentos saludables. Los niños no tuvieron acceso a las comidas escolares que recibían en sus escuelas o guarderías y el precio de los alimentos aumentaba al tiempo que millones perdían sus empleos. La seguridad alimentaria se tambaleaba. Fue entonces cuando a nivel, federal y estatal, se implementaron medidas de emergencia para proporcionar alimentos y dinero en efectivo para mitigar el golpe a la seguridad alimentaria.
Investigadores del Instituto de Políticas sobre Nutrición,(NPI) un centro de investigación de la División de Agricultura y Recursos Naturales de California, UCANR que vela por la salud y nutrición de las familias, evaluaron las medidas implementadas, durante COVID-19, que ayudaron a brindar apoyo a las familias de bajos ingresos. El resultado es importante porque demuestra como ciertos programas sociales como: las comidas escolares universales, el EITC y WIC, representan un enfoque integral para promover que los alimentos saludables sean accesibles para todos.
He aquí sus observaciones:
Las comidas escolares universales y sus beneficios
El Programa Nacional de Almuerzos Escolares y el Programa de Desayunos Escolares satisfacen cada día las necesidades de alimentación y nutrición de 30 millones de estudiantes de primaria y secundaria en todo el país. Normalmente, los estudiantes de familias que cumplen los criterios de elegibilidad de ingresos reciben comidas escolares gratis o a precio reducido, mientras que otros pagan precio completo.
Las investigadoras de NPI, Wendi Gosliner, científica del proyecto, y Lorrene Ritchie, directora y especialista de Extensión Cooperativa de la UC, codirigen estudios sobre las comidas escolares en California en colaboración con investigadores del laboratorio para la nutrición y la inclusión NOURISH quienes también investigan sobre las comidas escolares en Maine y otros estados.
Durante COVID-19 y debido el cierre de las escuelas, en marzo 2020, el Congreso autorizó que el programa de comidas escolares gratuitas se ampliara a todos los estudiantes con el propósito de detener el aumento de la inseguridad alimentaria en las familias con niños en edad escolar. Esa disposición federal, se terminó en el año escolar 2021-2022. Sin embargo, debido a la importancia, que tienen las comidas escolares universales en la salud y el éxito académico de los estudiantes, algunos estados continúan proporcionándolas con fondos estatales.
California fue el primer estado en adoptar el Programa Estatal de Comidas Universales, en el año escolar 2022-23.Con una inversión de 650 millones de dólares para el desarrollo de infraestructura de las cocinas escolares, entrenamiento de personal, y asistencia técnica en las escuelas. Esa inversión incluye además, a los programas de la Granja a la Escuela y otros mecanismos de las comidas escolares. Maine y otros estados también adoptaron las comidas escolares universales hasta el año escolar 2022-23.
“Los estados actúan a menudo como incubadoras, si las cosas funcionan bien a nivel estatal, esos programas, se convierten, a veces en política federal”, dijo Gosliner. Así es como, la identificación del éxito de los programas -así como sus retos- podría ayudar a que los legisladores reconsideren en las políticas, a nivel estatal y nacional, la importancia de las comidas escolares universales en la salud y el éxito académico de los estudiantes.
Por lo pronto, dos investigaciones realizadas en California y Maine , entre el personal responsable de la alimentación escolar, ya han permitido documentar los beneficios de las comidas escolares universales. En California, de un total de 581 líderes de servicios alimentarios escolares encuestados, alrededor de la mitad (45.7 por ciento) reportaron que hubo una reducción en el estigma estudiantil gracias a que las comidas escolares se ampliaron a todos los estudiantes. Algo similar sucedió en Maine, entre los 43 participantes, más de la mitad (51 por ciento) también reportaron una disminución en el estigma. Ambos estudios encontraron un aumento en la participación estudiantil. Lo que sugiere que las comidas escolares universales están cumpliendo con el propósito de incrementar la participación y ofrecer comidas nutricionalmente balanceadas para todos.
Sin embargo;cuando el niño sale de la escuela, la responsabilidad de servir una comida nutritiva a la hora de la cena recae en quien lo cuida.
“Las comidas escolares universales ofrecen alimentos y son un apoyo al presupuesto familiar ya que muchas familias no tienen el ingreso, ni tiempo, ni los recursos adecuados para adquirir suficientes alimentos y bebidas saludables”, señaló Gosliner.
Hay otros programas públicos que son cruciales para el bienestar de las familias y niños. Un ejemplo, es el Crédito Tributario por Ingreso de Trabajo o EITC, por sus siglas en inglés.
Muchas familias elegibles no reclaman, el reembolso de impuestos
El Crédito Tributario por Ingreso del Trabajo es el programa más importante en la lucha contra la pobreza. Es un ingreso suplementario importante que puede aportar hasta 7 mil dólares por año para una familia. Sin embargo; a pesar que se conoce bien este beneficio en la calidad de vida de las familias de bajos ingresos, los estudios indican que muchas familias elegibles NO participan. Tan solo en 2018, California perdió 2 mil millones de dólares en impuestos no reclamados.
Gosliner dirigió un estudiopara documentar los niveles de concientización, barreras y beneficios en la participación del EITC que encontró que un número importante de las familias jóvenes, en donde se habla otro idioma que no es inglés, hay menos conocimiento del reembolso y por lo tanto, tienen menos posibilidades de recibirlo. Razón por lo que las autoras de la investigación presentan las siguientes recomendaciones:
- Simplificar el proceso para obtener el reembolso y ofrecer mayor seguridad para aumentar la participación,
- Proporcionar más información a las familias que cumplen con los requisitos para obtener el EITC.
- A largo plazo, estas estrategias pueden reducir la pobreza y mejorar la salud de los niños.
El aumento del monto para la compra de frutas y verduras es un beneficio para la salud
Además de las comidas escolares universales y el EITC, las familias de bajos ingresos pueden ser elegibles para recibir WIC o Programa Especial Suplementario de Nutrición para Mujeres, Infantes y Niños, un suplemento, que ofrece a mujeres con niños, de hasta cinco años, ayuda para la alimentación, educación de nutrición y acceso a otros servicios sociales y de salud.
Uno de los beneficios de los paquetes de alimentos del WIC, es la prestación en efectivo, Cash Value Benefit, que proporciona una cantidad fija en dólares para la adquisición de frutas y verduras. Durante la pandemia, el Departamento de Agricultura de los Estados Unidos aumentó esta prestación de 9 a 35 dólares al mes, cantidad que se modificó, posteriormente, a 24 dólares al mes por niño en octubre de 2021.
Ritchie indica que todos estos cambios han ayudado a recopilar más pruebas sobre la importancia de WIC en la salud infantil.
“Nueve dólares solo compran la cuarta parte del tipo de alimentos que un niño debe comer diariamente”, manifestó Ritchie. “El incremento en el Cash Value Benefit durante la pandemia fue una medida ideal para investigar su impacto”.
En colaboración con Shannon Whaley y su equipo en el Public Health Foundation Enterprises-WIC, NPI ejecutó un estudio, entre casi dos mil participantes de WIC en California, que demostró que el incremento en el Cash Value Benefit ayudó a las familias a adquirir más frutas y verduras.
“El incremento de Cash Value Benefit a las familias de WIC amplia el acceso a las frutas y verduras y permite que los niños puedan probar nuevos alimentos. Probar todo tipo de alimentos es crucial para establecer hábitos saludables para toda la vida”, señaló Ritchie.
Los investigadores descubrieron que el incremento en WIC ayudó a reducir la inseguridad alimentaria y se espera que el aumento en la satisfacción del programa se traduzca también en la inscripción de más familias elegibles. En noviembre del 2022, el Departamento de Agricultura de Estados Unidos propuso que el incremento en el Cash Value Benefit sea algo permanente en WIC.
En el 2021, todas las agencias estatales de WIC participaron en una encuesta de satisfacción de WIC que mostró que el consumo de frutas y verduras en los niños en el programa WIC aumentó en promedio en un tercio de taza, es un aumento importante, tomando en cuenta el beneficio en toda la población que recibe WIC.
La investigación del NPI sobre las comidas escolares universales, el EITC y WIC conforman una pequeña parte de un enfoque integral para promover que los alimentos saludables sean accesibles para todos.
NPI realiza una amplia variedad de investigaciones en torno a la salud y nutrición y otros aspectos de la alimentación saludable como el acceso al agua potable segura, el cuidado infantil y la educación sobre nutrición. Para más información visite el sitio web del Instituto de Políticas sobre Nutrición.
Adaptado al español por Leticia Irigoyen del artículo en inglés
Editado para su publicación por Norma De la Vega
Winter atmospheric rivers gave pathogens, diseases path to infect crops
Outbreaks similar to El Niño-influenced issues of the 1990s
The wave of atmospheric rivers that swept across the state this winter has created the right conditions for plant pathogens that haven't been seen for decades in California. University of California, Davis, plant pathologist Florent “Flo” Trouillas is getting more calls from growers and farm advisors concerned about potential crop damage.
“Generally, whenever you have rain events, you're going to have problems,” said Trouillas, a Cooperative Extension specialist who is based at the Kearney Agricultural Research and Extension Center in Parlier. “In wet years we get really busy because most pathogens need and like water.”
Trouillas is like a disease detective. He splits his time between the field and the lab, working to diagnose pathogens, diseases and other ailments that strike fruit and nut crops such as almonds, cherries, olives and pistachios.
On a recent visit to an almond orchard near Fresno, Trouillas joined Mae Culumber, a nut crops farm advisor for UC Cooperative Extension Fresno County. A few weeks earlier, the two had walked the orchard, taking note of the base of some trees that had gumming — a thick, jelly-looking substance indicating a pathogen had taken hold.
“A lot of what Florent is doing is trying to assess patterns on a landscape,” Culumber said. “Sometimes things may look like they are one thing, but it could be another problem.”
When the two returned weeks later, the amber-colored gumming had moved into the canopy, looking like gumballs stuck to branches, some of which were already dead. “It's getting out of control from before,” Trouillas says. “This branch was killed. This is widespread.”
From the field to the lab
Lab testing confirmed what Trouillas believed was the culprit: Phytophthora syringae, a pathogen that can affect almond crops but is rarely seen in California. If it is found, generally the site of infection are wounds caused by pruning, but that is not the case here, where the infection began in the canopy at twigs, or small branches.
It is a threat to a key crop, which according to the California Department of Food and Agriculture, generates $5 billion annually. The last time Phytophthora syringae hit California was in the 1990s after a series of El Niño-influenced storms. Trouillas, who has a photographic memory, remembered reading about it in an old manual.
“It's rare for California and one that we see mostly following atmospheric rivers,” he says.
“The disease will only happen following these extremely wet winters.”
Phytophthora is soilborne, mostly found in tree roots, and doesn't generally spread up into branches. But the intense storms created the right conditions for the pathogen to “swim” up trunks as winds blew spores into the air and rain dropped them back down into the canopy, Trouillas said.
Some of the trees in this orchard will die; others can be saved by pruning infected branches and applying a recommended fungicide, he said.
Identification, diagnosis, education
Trouillas is one of more than 50 Cooperative Extension specialists at UC Davis and each is charged with identifying problems and developing solutions for those issues in support of agriculture, the ecosystem and communities throughout the state.
In his role, Trouillas focuses not only on pathology and research but also on educating growers, nursery staff, pest control advisers and others in agriculture about ways to manage potential threats and how to prevent crop damage.
“His role is very crucial,” said Mohammad Yaghmour, an orchard systems advisor for UC Cooperative Extension Kern County. “He's not only on this mission to educate growers but he's also a source of education for us.”
Trouillas typically conducts one or two site visits a week, usually after a farm advisor reaches out about a problem they can't solve on their own.
“This allows us to be at the forefront of disease detections in California,” he said.
He likens these visits to house calls a doctor would make, only to fields instead. And one of those calls recently took him to a cherry orchard in Lodi.
“These guys help me quite a bit,” said Andrew Vignolo, a pest control adviser with Wilbur-Ellis who asked for a consult. “I bug them a lot.”
The visit starts like any consult in a doctor's office, only the questions come fast as they walk around the Lodi orchard where branches are dying, there is gumming and the trees appear stressed. Some look to be sunburned from exposure. Old pruning wounds show cankers, indicating that past disease treatments didn't get rid of whatever was affecting the trees.
Trouillas asks about the cultivar of the trees because some varieties are more susceptible to pests or diseases. He focuses on stress because that opens the door to disease.
Do they prune in the dormant winter months or in summer when pathogens are more prevalent? Does the soil get tested? How old are the trees? What about nutrition?
“I'm trying to figure out how they got infected so bad,” Trouillas said, walking the orchard. “Bacterial canker is a very mysterious disease.”
He thinks it might be a bacterial canker disease and shaves some bark to take to the lab for testing. He wants to come back next winter to take some samples to see where the pathogen is overwintering.
“We'll know in a few weeks if we have a fighting chance,” Vignolo said.
Be it Lodi, Fresno or elsewhere in the state, Trouillas focuses on local conditions. But what is learned in one field can be passed on to others, providing early warnings or advice for those in similar situations. “All these efforts at collaboration, from the field, to the lab, going through research projects, there's only one goal here — to help the farmers of California.”/h3>/h3>/h3>
Indigenous science key to adapting to climate change
UC Berkeley and Karuk Tribe use Indigenous and western science to cultivate resilient food systems under changing climate conditions.
To adapt to climate change, Karuk Tribe members identified the importance of monitoring climate stress on plant species and actively managing and restoring healthy ecosystem processes to increase the consistency and quality of their food harvests, according to a new report. The Karuk Tribe's Aboriginal Territory encompasses over a million acres in the Klamath Basin in Northern California and Southern Oregon.
The Karuk Tribe-UC Berkeley Collaborative has released findings from its four-year collaborative research in their report “Karuk Agroecosystem Resilience and Cultural Foods and Fibers Revitalization Initiative: xúus nu'éethti – we are caring for it.”
To assess climate-change impacts on cultural-use plants and their habitats and to develop strategies and tools for long-term monitoring, this project integrated Indigenous and western science perspectives.
“Understanding the breadth and intensity of climate change with regard to our cultural resources is key to developing adequate response plans,” said Karuk cultural practitioner and project co-lead Lisa Morehead-Hillman. “Without healthy stands (of trees), our cultural practices suffer. We all suffer.”
The report authors lay out specific place-based management and monitoring actions that will enhance the resilience of cultural focal species and habitats to climate change, climate variability and management threats.
To support the resilience of Indigenous cultural agroecosystems and cultural food and fiber species, as well as strengthening Indigenous food sovereignty now and into the future, the authors recommend the following management, policy, research and institutional actions:
• Supporting Karuk Tribal natural resource, data and knowledge sovereignty through appropriate engagement and Tribal oversight.
• Investing in Tribal management infrastructure and workforce development to support culturally appropriate, place-based job opportunities for Tribal members and descendants.
• Supporting co-management and family-based stewardship of cultural use plants and habitats on Karuk Aboriginal lands.
• Investing in and supporting the re-acquisition of Karuk Aboriginal lands to build back the Tribal land base and restore habitats and ecosystems.
• Funding research, monitoring, and educational opportunities that can support youth leadership development, job creation, agroecosystem resilience, and food sovereignty in Karuk Aboriginal Territory.
This research builds on the findings from a five-year Karuk Tribe-UC Berkeley Collaborative food security project (2012-2018), which found that 92% of all Tribal households in the Klamath River Basin experienced some level of food insecurity, and that having access to cultural foods was a strong predictor of food security, yet only 7% of all Tribal households had access to good quality cultural foods at all times.
“This project applies what we learned from tribal members about food insecurity and climate and land management threats to cultural foods to the landscape level, co-creating methods and tools with our Karuk colleagues to assess and restore the health, quality and abundance of cultural foods and fibers to promote food security and eco-cultural resilience,” said Jennifer Sowerwine, lead UC Berkeley collaborator and associate professor of Cooperative Extension.
Research objectives centered around the “Agroecosystem Condition Assessment,” in which UC Berkeley and Karuk researchers and cultural practitioners assessed the health, quality and yield of 20 cultural-use focal plants prioritized by the Karuk Tribe, such as tanoak acorns, evergreen huckleberry, bear grass and hazel, as well as the condition of their habitats.
“This project demonstrates the benefits of working with a diverse research partnership in the co-production of climate science using blended Indigenous and Western research and monitoring methods,” said project collaborator Frank Lake, research ecologist and USDA Forest Service Pacific Southwest tribal liaison. “This project exemplifies recent federal directives and initiatives to support tribes for climate adaptation, forest restoration and eco-cultural revitalization.”
The overall quality and condition of most of the focal species found in the research plots and patches reflect both the devastating impact of colonial land-management practices – including timber harvest, fire exclusion and mining – as well as clear evidence of climate stress such as aborted fruit, early die back and poor-quality product. Forced exclusion of cultural management is reflected in encroachment of invasive species, inappropriate canopy cover and poor-quality harvests impacting both human and animal access to these important plant resources.
“This work done among Indigenous knowledge holders and academia is paramount to developing and sustaining a well-trained workforce for the future,” said Bill Tripp, director of the Karuk Tribe Department of Natural Resources and project co-lead. “We have a long way to go in realizing cultural relevancy in addressing the systemic injustices that plague our people, accelerate climate change, and work against ecosystem process and function.”
Based on research findings informed by the deep insights of Karuk natural resources managers, Karuk elders and cultural practitioners, the report outlines recommendations for restoring key habitats and revitalizing culturally significant species to enhance agroecological resilience in Karuk Aboriginal lands, which are concurrently administered, managed and occupied by U.S. Forest Service and private landowners.
Kathy McCovey, a Karuk cultural practitioner, archaeologist, forest ecologist and project collaborator, explained the cultural significance of the project:
“Through this project, we are learning how to reconnect with place,” McCovey said. “In learning about and tending these areas, we are tending our family gardens. It's all about people in place. Working on this project, we are working to bring these places back to life. We're rediscovering their Karuk names and how those names signal traditional uses of plants in those places. That way we can reconnect with the places our families come from”.
“The whole river system is full of knowledge,” she elaborated. “It's a crucial time for the Karuk people to tend these areas and learn how to take care of them. This community has knowledge that's developed and evolved with these lands and we have a responsibility to support the plants in these areas. We had our land stolen out from under us, but we still live here, we still know how to tend and gather plants, we still have our knowledge and our ceremonies. We still have the ability to go out and gather from the land. We still know how to take care of this place. We take care of the land and it takes care of us.”
This project serves as an example of how university and federal agency researchers can partner with California tribes to lift up Indigenous knowledge, which can help all involved to better understand and develop solutions to the climate crisis and its effects on California's landscapes and biodiversity, especially on species of cultural significance to Indigenous communities.
Funding for the project was provided by a grant from the USDA NIFA Agriculture and Food Research Initiative Resilient Agroecosystems under Changing Climate Challenge Area.
Download the free report at the Karuk-Berkeley Collaborative website: https://nature.berkeley.edu/karuk-collaborative/wp-content/uploads/2023/03/Karuk-Resilience-Report_Smallest-file-size.pdf/h3>
Lambs grazing on pastures after wildfire show no significant adverse effects
Hopland REC turns 2018 River Fire devastation into research opportunity
The destructiveness of wildfire flames is easy to see, but dangers may lurk in the ashes they leave behind. A group of UC Davis scientists studied lambs at the UC Hopland Research and Extension Center, investigating whether pastures regrown after a wildfire cause toxic metal residues in grazing animals. The results, published in California Agriculture journal, showed that grazing on regrown pastures did not significantly alter the metal content of the lambs' meat and wool. That's good news for ranchers and consumers from a food safety perspective.
In 2018, the River Fire burned six miles north of Hopland, scorching two-thirds of the land at Hopland REC, including areas in its sheep station. Since Hopland REC conducts ecological and agricultural research, they had data and some meat samples from the sheep flock that lived on site before the River Fire occurred.
“A bunch of researchers came together to brainstorm how we could take advantage of this unfortunate event,” said Sarah Depenbrock, assistant professor and agronomist in the Medicine and Epidemiology department of UC Davis School of Veterinary Medicine.
Burning has played a role in agricultural processes for many years, but wildfires in California are creating a new fire landscape that interests researchers like Depenbrock. “The problem, now, is that these big wildfires probably interact with agricultural land differently than routine prescribed burns,” she said.
Large, older plants on lands that have not recently burned may contain high concentrations of metals, sequestered over years of growth. Mercury is an example of a potentially dangerous metal that can be sequestered in living things over time. These metals may be distributed in ash after the vegetation burns so the scientists examined lambs that had grazed on Hopland REC's recently burned pastures, during the first plant regrowth.
Uncertain results raise more questions
The researchers compared meat from lambs that grazed on regrown pastures in 2019, after the River Fire, to frozen meat samples that were collected the year before the fire. Lead, mercury, arsenic, molybdenum, cadmium, beryllium, cobalt and nickel were not detected in any animal samples. There were, however, a few (3 out of 26) samples that tested positive for the non-essential (potentially toxic heavy metals) chromium and thallium in the group grazing after the fire.
Due to the small number of samples testing positive, researchers could not determine statistically if this contamination was associated with grazing the burn regrowth. The concentrations of chromium and thallium found may or may not be potentially toxic, depending on the specific forms and how much meat a person consumes.
Another aspect of the study included testing lambs' wool to determine if it is a good method of judging the mineral content of its meat. “In general, we learned that it wasn't well-correlated with most meat metal content of interest, which is worth knowing. However, because we did not identify many of the non-essential metals of particular toxologic concern, such as lead or mercury, in any animal samples we could not determine if testing wool would be useful for those metals, as they are in other species,” said Depenbrock. She also notes that the wool from animals whose meat tested positive for chromium and thallium, did not test positive for these metals in their wool.
As the challenges in managing wildfires persist, so does the risk of contamination of food products stemming from grazing livestock.
“We didn't get striking evidence that tells us, when there's a fire, it means everything is contaminated with heavy metals,” said Depenbrock. “But it does raise the question that maybe we should be doing a little bit of surveillance to see if this is spurious or common. And we should be finding a way to screen grazing herds.”
Recommendations to manage copper concerns
“It's a very small study, but it was quite interesting to find that copper was actually lower in the postfire grazing group, which makes me wonder,” Depenbrock said.
Diseases associated with copper deficiency are a major concern in sheep. For example, congenital swayback can result in stillbirth or an animal's inability to stand on its own due to incurable changes to the spinal cord. Other adverse effects include reduced growth rate, anemia, wool defects and fiber depigmentation, and osteoporosis with higher risk of spontaneous fractures. Copper excess can also cause serious and sometimes fatal disease.
Many of the forage sources, grazing areas and rangelands in California are copper deficient, while some feed sources have excess copper. Screening and monitoring livestock herds for trace minerals including copper is crucial.
To test for copper, she advises livestock owners to obtain mineral concentrations from the organs of euthanized or dead animals. Samples from the liver and kidney are the most valuable organs to identify a potential problem in the herd. UC Davis Veterinary Medicine's California Animal Health and Food Safety (CAHFS) labs do this testing routinely.
Second, monitor and record mineral supplementation and, third, maintain updated health records to make informed decisions regarding supplementation based on a herd or flock's known problems. For example, if a producer is not accustomed to supplementing copper, Depenbrock highly recommends working with a veterinarian to start out (as there are numerous copper supplement products of varying concentration on the market), to determine a testing or screening plan, and review health records for problems potentially associated with copper.
To read the full text of the study, visit https://calag.ucanr.edu/Archive/?article=ca.2022a0016.
Key climate data added to enhance grower decision-support tool
Free CalAgroClimate tool helps growers protect crops from frost and extreme heat
California farmers can see how climatic conditions that may affect agriculture are changing in their regions by using CalAgroClimate so they can make strategic changes. Nine new agriculturally important climate indicatorshave been added to the decision-support tool created by UC Cooperative Extension and U.S. Department of Agriculture scientists.
These new tools use a high-resolution climate dataset called PRISM to provide location-specific or county-aggregated long-term trends in agroclimatic indicators from 1980 to last year. These new agroclimate indicators include Frost Days, Last Spring Freeze, First Fall Freeze, Freeze-Free Season, Tropical Nights, Hot Days, Extreme Heat Days, Heatwaves and Diurnal Temperature Range (see definitions below). These indicators were derived from a study published in the journal Agronomy.
All of the new tools are free and available on CalAgroClimate for anyone to access.
“Frost-related tools such as Frost Days, Last Spring Freeze, First Fall Freeze, and Freeze-Free Season can help farmers and agricultural clientele make informed long-term choices,” said Tapan B. Pathak, UC Cooperative Extension specialist in climate adaptation in agriculture based at UC Merced, who is leading the CalAgroClimate project.
“For instance, if you are planning to invest in a frost sensitive crop in your region, these indicators can provide valuable information on whether frost risk has changed over time and whether it is less risky to make such an investment,” he said. “Wine grapes, for instance, are very sensitive to frost. Although not all frost events are damaging, understanding long-term trends in frost can help in making long-term strategic decisions such as whether to invest in frost protections.”
Another set of new agroclimatic indicators, on CalAgroClimate – Tropical Nights, Hot Days, Extreme Heat Days, Heatwaves and Diurnal Temperature Range – are based on higher maximum and minimum temperatures. Tropical Nights, for instance, calculates total number of nights when overnight temperatures exceed 68 F. More frequent tropical nights can increase crop respiration rates and can be detrimental for fruit quality and quantity, increase the risk of damage from pathogens, and potentially impact fruit set and yield.
Knowing how trends are evolving over time can assist growers in managing their crops to reduce risks. Similarly, growers can easily look at trends related to heat – hot days, extreme heat and heatwaves – on CalAgroClimate to assess their options on what they need to do to be adaptive. In the short term, growers may put up shade or for longer term, choose varieties that are more heat-tolerant.
“In recently published work, one of the farmers in the Central Valley told us, ‘When you really see so much difference in a short amount of time in your immediate area…we would have to look at that and say, well, we're going to have to adapt varieties because this is a 20- or 25-year planting and we're going to have to find crops or varieties that will adapt to that,'” Pathak said.
Another farmer told us, “Knowing what's going to happen or at least having a good idea, if you know something's going to be become or won't be viable, then obviously you're going to try to phase that out, and phase in something that's better suited.”
Pathak added, “The new agroclimatic indicators on CalAgroClimate provide a reality check on how conditions are changing in short and long-term, what it means for farmers and to assist them on deciding what they need to do to be adaptive. These tools will greatly benefit farmers and agricultural clientele in assessing risks and making informed decisions.”
Other collaborators include StevenOstoja and Lauren Parker of theUSDA California Climate Hub,PrakashKumarJha of UC Agriculture and Natural Resources and Robert Johnson and ShaneFeirer of UC Agriculture and Natural Resources' Informatics and Geographic Information Systems.
Definitions of AgroClimatic Indicators:
Frost Days are days in a year with minimum temperature below or equal to 32F.
Last Spring Freeze is the latest day in spring when minimum temperature is below or equal to 32F.
First Fall Freeze is the earliest day in fall when minimum temperature falls to 32F or below.
Freeze-Free Season is the time between the last spring and first fall freeze, represented by the number of consecutive days in a year without freezing temperatures.
Tropical Nights are number of nights when temperatures exceed 68F.
Hot Days are the days per year with maximum temperature exceeding 100 °F.
Extreme Heat Days are the number of days per year with maximum temperatures warmer than the 98th percentile of historical summer maximum temperature for the selected location.
Heatwaves are events that occur when extreme heat lasts for at least three consecutive days.
Diurnal Temperature Range is the difference between daily maximum and minimum temperatures./h3>/h2>