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Short-term methane emissions from two dairy farms in California estimated by different measurement techniques and US Environmental Protection Agency inventory methodology: A case study
Get PDFAtmospheric top-down measurements have attributed up to twice the methane (CH4) emissions of bottom-up (BU) inventories to dairy production. We explored this discrepancy by estimating CH4 emissions of two dairy facilities in California with U.S. Environmental Protection Agency (USEPA) methodology, which is used for BU inventories, and three independent measurement techniques: 1) open-path measurements with inverse dispersion modeling (hereafter “open-path”); 2) vehicle measurements with tracer flux ratio method; and 3) aircraft measurements with closed-path method. All three techniques estimated whole farm CH4 emissions during one week in the summer of 2016. In addition, open-path also estimated whole farm CH4 emissions during two months in the winter of 2017. The objectives of the present study were: 1) to compare the different techniques to measure whole farm CH4 emissions from dairies, 2) to estimate CH4 emissions from animal housing and liquid manure storage, and compare them to USEPA inventory estimates, and 3) to compare CH4 emissions between the two dairies. Whole farm CH4 estimates were similar among measurement techniques. No seasonality was detected for CH4 emissions from animal housing, but CH4 emissions from liquid manure storage were three to six times greater during the summer than during the winter. Open-path estimates for liquid manure storage emissions were similar to monthly USEPA estimates during the summer but not during the winter, and neither open-path estimates from summer nor winter were similar to the annual USEPA estimate. Thus, CH4 emissions need to be measured throughout the year to evaluate annual inventories. Methane yields from housing and liquid manure storage were used to compare emissions between the farms. While CH4 yields from animal housing were similar (on average 20.9 g CH4/kg dry matter intake), CH4 yields from liquid manure storage at one dairy were 1.7 and 3.5 times greater than at the other dairy during summer (234 vs. 137 g CH4/kg volatile solids [VS]) and winter (78 vs. 22 g CH4/kg VS), respectively. This greater CH4 yield was attributed to the greater proportion of manure stored in liquid form, which suggests that the promotion of manure management practices that reduce the amount of manure solids stored in liquid form, such as manure separators, could significantly reduce CH4 emissions from dairies. These results demonstrate that multiple techniques for monitoring emissions on these farms were comparable
Mineral fertilizer and manure effects on leached inorganic nitrogen, nitrate isotopic composition, phosphorus, and dissolved organic carbon under furrow irrigation
Get PDFTo improve nitrogen (N) use efficiency in irrigated agriculture, a better understanding is needed of mineral fertilizer and manure effects on nutrient leaching in a furrow irrigated silt loam in southern Idaho. In this 2003-to-2006 field study, we measured deep percolation fluxes at 1.2-m depth and associated nutrient concentrations and mass losses for dairy manure-N or mineral-N (urea, sodium nitrate [NaNO3]) amended soils (372 kg available N/ha in four years) and non-amended controls, and determined the 2H-H2O and 18O-H2O isotope ratios in the leached nitrate. Flow-weighted concentration means for individual irrigations varied widely, from near zero to as much as 250 mg/L for NO3-N, 480 µg/ L for dissolved reactive phosphorus (DRP), 43 mg/L for dissolved organic C (DOC), and 390 mg/L for chloride (Cl). Relative to other treatments, mineral fertilizer increased NO3-N (3.3x) and Cl (4.4x) concentrations in deep leachate, particularly when NaNO3 was applied in 2004, and produced maximum mean season-long NO3-N and Cl losses. Manure and control treatments produced similar leachate nutrient mass losses, and for some irrigation periods, mineral fertilizer produced 85% and 97% lesser DRP losses and 2x greater Cl losses compared to manure and control treatments. Four-year cumulative losses among treatments differed only for Cl. Isotopic composition of deep leached nitrate indicate that both transformation and biologic cycling of mineral and manure N are rapid in these soils, which, with percolation volume, influence the amounts of NO3-N and DOC leached. In light of the potential negative effects associated with either fertilizer type, and because even non-amended soils produced substantial amounts of leached NO3-N (69.5 kg ha-1 Yr-1), an important management key for limiting nutrient losses in these fertilized, furrow-irrigated soils is to minimize percolation water losses
Registration of FC1740 and FC1741 multigerm, rhizomania-resistant sugar beet germplasm with resistance to multiple diseases
Get PDFFC1740 (Reg No. GP-293, PI 681717) and FC1741 (Reg No.
GP-294, PI 681718) sugar beet germplasm (Beta vulgaris L.)
were developed by the USDA-ARS at Fort Collins, CO, Salinas,
CA, and Kimberly, ID, in cooperation with the Beet Sugar
Development Foundation, Denver, CO. These germplasm
are diploid, multigerm sugar beet populations in normal
cytoplasm, segregating for self-sterility (Sf:SsSs), genetic male sterility (A:aa), and hypocotyl color (R:rr). FC1740 and FC1741 have excellent resistance to rhizomania (Beet necrotic yellow vein virus). FC1740 was selected as homozygous resistant to markers linked to both Rz1 and Rz2 genes for rhizomania resistance. FC1741 was selected as homozygous to the marker linked to the Rz2 gene for resistance. Both germplasm also have resistance to beet curly top (Beet curly top virus) and Fusarium yellows (Fusarium oxysporum Schlechtend.:Fr. f. sp. betae (D. Stewart) W. C. Snyder & H. N. Hans. and other Fusarium spp.), as well as moderate resistance to Aphanomyces root
rot (Aphanomyces cochlioides Drechs.). Neither line exhibited resistance to Cercospora leaf spot (Cercospora beticola Sacc.), Rhizoctonia crown and root rot (Rhizoctonia solani Kuhn.) or sugar beet root aphid (Pemphigus spp.). These germplasm provide sources from which to select disease-resistant, multigerm pollinator parents with either or both of the Rz1 and Rz2 sources of rhizomania resistance. Because they are from the same population, they also are useful as controls of known genetic background in comparing entries screened for rhizomania resistance conditioned by Rz1 or Rz2
Wine grape cultivar influence on the performance of models that predict the lower threshold canopy temperature of a water stress index
Get PDFThe calculation of a thermal based Crop Water Stress Index (CWSI) requires an estimate of canopy temperature under non-water stressed conditions. The objective of this study was to assess the influence of different wine grape cultivars on the performance of models that predict canopy temperature non-water stressed wine vines. The canopy temperature of the wine grape cultivars Malbec, Syrah, Chardonnay and Cabernet franc were measured under well-watered conditions over multiple years and modeled as a function of climatic parameters solar radiation, air temperature, relative humidity and wind speed using multiple linear regression and neural network modeling. Despite differences among cultivars in non-water stressed canopy temperature, both models provided good prediction results when all cultivars were collectively modeled. All predictive models had an uncertainty of plus or minus 0.1 in calculation of the CWSI despite significantly different prediction error variance between models
Incidence, distribution, and pathogenicity of fungi causing root rot in Idaho long-term sugar beet storage piles
Get PDFFungal rots in sugar beet roots held in long-term storage can lead to considerable sucrose loss, but the incidence and distribution of fungal rots inside sugar beet piles and pathogenicity for some species is poorly understood. Thus, Idaho sugar beet held in five outdoor and two indoor piles in 2014 and 2015 were investigated. The root surface area covered by fungal growth, and discolored and healthy tissue was assessed in nine one-meter square areas per pile using a stratified random sampling design. Pathogenicity was evaluated indoors via plug inoculation in 2015 and 2016. Botrytis cinerea covered more (P <0.0001) of root surface area (6 to 22%) inside indoor piles than outdoor piles (0 to 3%). No trends were evident for the Athelia-like sp. (0 to 15%) and Penicillium-like spp. (0 to 8%). Penicillium-like isolates were comprised of the following species: 60% P. expansum, 34% P. cellarum, 3% P. polonicum, and 3% Talaromyces rugulosus. Trace levels (<1% of root surface) of other fungi including Cladosporium and Fusarium were evident on roots and in isolations. Based on sample location in a pile there were no trends or differences, but two outdoor piles (OVP1 and OVP2) had more (P <0.0001) healthy tissue (90-96%) than other piles (28-80%). When the pathogenicity tests were analyzed by species, all the species had significantly different (P <0.0001) levels of rot (in mm): B. cinerea (61), P. expansum (35), P. polonicum (31), P. cellarum (28), Athelia-like sp. (21), T. rugulosus (0), and non-inoculated check (0). The OVP1 and OVP2 piles had negligible fungal growth indicating proper storage can be achieved through tarped vent piles
Identifying challenges and opportunities for improved nutrient management through U.S.D.A's Dairy Agroecosystem Working Group
Get PDFNutrient management is a priority of U.S. dairy farms, although specific concerns vary across regions and management systems. To elucidate challenges and opportunities to improving nutrient use efficiencies, the USDA’s Dairy Agroecosystems Working Group investigated 10 case studies of confinement (including open lots and free stall housing) and grazing operations in the seven major
U.S. dairy producing states. Simulation modeling was carried out using the Integrated Farm Systems Model over 25 years of historic weather data. Dairies with a preference for importing feed and exporting manure, common for simulated dry lot dairies of the arid west, had lower nutrient use efficiencies at the farm gate than freestall and tie-stall dairies in humid climates. Phosphorus (P) use efficiencies ranged from 33 to 82% of imported P, while N use efficiencies were 25 to 50% of imported N. When viewed from a P budgeting perspective, environmental losses of P were generally negligible, especially from dry lot dairies. Opportunities for greater P use efficiency reside primarily in increasing on-farm feed production and reducing excess P in diets. In contrast with P, environmental losses of nitrogen (N) were 50 to 75% of annual farm N inputs. For dry lot dairies, the greatest potential for N conservation is associated with ammonia (NH3) control from housing, whereas for freestall and tie-stall operations, N conservation opportunities vary with soil and manure management system. Given that fertilizer expenses are equivalent to 2 to 6% of annual farm profits, cost incentives do exist to improve nutrient use efficiencies. However, augmenting on-farm feed production represents an even greater opportunity, especially on large operations with high animal unit densities
Furrow infiltration and erosion data 1998 to 2016
No full textThe data are derived from the field monitoring of irrigated furrows from 1998 to 2016 at the research farm of the USDA/ARS-NorthWest Irrigation and Soil Research Laboratory in Kimberly, Idaho, U.S. For each monitored furrow, irrigation inflow rates, outflow rates, and sediment concentrations were recorded periodically during the irrigation. The field data for each study or year were analyzed using the WASHOUT program (Lentz and Sojka, 1995). The WASHOUT program produces an output file (filename.out), which become components of this Ag Data Commons data set. Data from many years and irrigations, furrows were measured at one or more locations along the furrow, as well as at the end (bottom) of the furrow. For each furrow position the data represent the flow, infiltration, and runoff information for the length of furrow, which begins at its inflow end (top of the field) and ends at the defined furrow position. This length is listed in the field data file for each furrow and irrigation. An ‘Irrigation Data Summary’ is included as a tab in the data set spreadsheet. This is a summary list of the studies and irrigations that are included in the data set. Also included is a PAM-Application-Codes tab that lists description of the polyacrylamide (PAM) treatments that were employed in some of the included studies
Tracking antibiotic resistance genes in soil irrigated with dairy wastewater
Get PDFIn southern Idaho, the application of dairy wastewater to agricultural soils is a widely used practice to irrigate crops and recycle nutrients. In this study, small-scale field plots were irrigated monthly (6 times) with dairy wastewater (100%), wastewater diluted to 50% with irrigation (canal) water, and diluted wastewater spiked with copper sulfate (50 mg Cu/L), while control plots were irrigated with canal water. In addition, half of all plots were either planted with wheat or were left as bare soil. Biweekly soil samples were collected during this period and processed to determine the occurrence and abundance of antibiotic resistance genes [blaCTX-M-1, erm(B), sul1, tet(B), tet(M), and tet(X)] and a class 1 integron-integrase gene (intI1) via quantitative real-time PCR (qPCR). Only sul1 and tet(X) were detected in soil (3 out of 32 samples) before the wastewater treatments were applied. However, the occurrence and relative abundance (normalized to 16S rRNA gene copies) of most genes [erm(B), intI1, sul1, and tet(M)] increased dramatically after wastewater irrigation and levels were maintained during the entire study period. blaCTX-M-1 was the only gene not detected in wastewater-treated soils, which is likely related to its absence in the dairy wastewater. Relative gene levels in soil were found to be statistically similar among the treatments in most cases, regardless of percentage of wastewater applied, presence or absence of plants, and level of copper in the wastewater. The key result from this study is that dairy wastewater irrigation significantly enlarges the reservoir of ARGs and intI1 in soils, while detection of these genes rarely occurred in soil irrigated only with canal water
Yield production functions of irrigated sugarbeet in an arid climate
Get PDFIncreased water demands and drought have resulted in the need to provide data to guide deficit water management decisions in irrigated sugarbeet (Beta vulgaris L.) production. The objective of this study was to quantify the yield response of sugarbeet to water input and actual crop evapotranspiration (ETa) on a soil type (silt loam) common to sugarbeet production in the Northwest U.S. These relationships are valuable to understanding sugarbeet response over a range of water availability and in developing tools to assess future production under water shortages. This paper consolidates data from three studies consisting of ten site-years from 2009 to 2016. The studies were at the USDA-Agricultural Research Service facility in Kimberly, ID on a Portneuf silt loam soil. Treatments consisted of varying levels of cumulative seasonal Kimberly-Penman ET model estimated crop evapotranspiration (ETc) rates ranging from rain-fed to 125% of ETc. Irrigation methods consisted of surface drip irrigation (3 site-years), linear/pivot overhead sprinkler (6 site-years), and solid-set sprinkler (1 site-year). Irrigation frequency was consistent for all studies with applications occurring 2 to 3 times per week depending on ETc demand. Estimated recoverable sucrose (ERS) yield and root yield were measured, and soil water contents were measured. Across all site-years, quantitative relationships between both actual crop ET (ETa) and water input, and sugarbeet yield and quality variables were developed. Significant (0.05 probability level) positive linear relationships were found between ETa and sugarbeet ERS and root yields (r2 = 0.78). Estimated recoverable sucrose and root yields increased at rates of 19.4 kg/ha/mm ETa and 0.13 Mg/ha/mm ETa, respectively. When ETa depths of 719 and 729 mm were reached by the crop, root and ERS yields were maximized, respectively. When water input (irrigation + precipitation) depths of 598 and 605 mm were, applied root and ERS yields were maximized, respectively. The quantitative relationships between both ETa and water input, and sugarbeet yields can be used to quantify sugarbeet production under deficit irrigation conditions (data derived from pivot/linear, drip, and solid set irrigation types), which may arise due to water shortage scenarios, or when drought occurs in non-irrigated areas
Experimental sugar beet cultivars evaluated for rhizomania resistance and storability in Idaho, 2016
Get PDFRhizomania caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious sugar beet production problems. To identify sugar beet cultivars with resistance to BNYVV and evaluate storability, 31 experimental cultivars were screened by growing them in a sugar beet field infested with BNYVV in Kimberly, ID during the 2016 growing season in a randomized complete block design with 6 replications. At harvest on 4-5 October 2016, roots were dug and evaluated for symptoms of rhizomania and also placed in an indoor commercial sugar beet storage building. After 130 days in storage, samples were evaluated for surface rot, weight loss, and sucrose loss. Surface root rot ranged from 4 to 31%, weight loss ranged from 6.7 to 12.3%, sucrose losses ranged from 18 to 52%, and estimated recoverable sucrose ranged from 2,901 to 11,290 lb/A. Given these response ranges, selecting cultivars for rhizomania resistance and combining this resistance with storability will lead to considerable economic benefit for the sugar beet industry