global sustainability depends on the recycling of organic wastes, containing carbon and plant nutrients, back into food production. Biosolids are capable of building total soil organic matter, but their ability to build stable organic C and n fractions is less well understood. The sequestration of stable soil C and replacement of energy-requiring commercial fertilizers both have implications for greenhouse gas mitigation. Our aim was to assess the effectiveness of biosolids amendments to store labile and stable soil C and n fractions while supplying crop n needs. Three rates of anaerobically digested biosolids were incorporated following wheat harvest every 4 yr in a wheat-fallow system over 20 yr, and compared to a no-fertilizer check and a standard commercial fertilizer treatment. Increases in total soil C and n correlated to cumulative application rates of total and acid-resistant, non-hydrolyzable (nH) C and n, with 91% of added biosolids C efficiently retained in soil. The soil accumulated light fraction (LF) C and n in biosolids treated plots, whereas the LF pools of the control plots decreased and LF pools in the commercial fertilizer plots stayed relatively constant. Total soil n correlated with cumulative biosolids n, with 35% of added biosolids n retained in the soil of which only 4% was stored in the soil nH n fraction. Anhydrous ammonia increased wheat yields by 27% over the 0-fertilizer check, without increasing soil n. Biosolids markedly elevated total, stable and LF soil C and n pools in semiarid conditions, while maintaining comparable wheat productivity to commercially fertilized wheat-fallow.

Climate-friendly best management practices for mitigating and adapting to climate change (cfBMPs) include changes in crop rotation, soil management and resource use. Determined largely by precipitation gradients, specific agroecological systems in the inland Pacific Northwestern U.S. (iPNW) feature different practices across the region. Historically, these farming systems have been economically productive, but at the cost of high soil erosion rates and organic matter depletion, making them win-lose situations. Agronomic, sociological, political and economic drivers all influence cropping system innovations. Integrated, holistic conservation systems also need to be identified to address climate change by integrating cfBMPs that provide win-win benefits for farmer and environment. We conclude that systems featuring short-term improvements in farm economics, market diversification, resource efficiency and soil health will be most readily adopted by farmers, thereby simultaneously addressing longer term challenges including climate change. Specific "win-win scenarios" are designed for different iPNW production zones delineated by water availability. The cfBMPs include reduced tillage and residue management, organic carbon (C) recycling, precision nitrogen (N) management and crop rotation diversification and intensification. Current plant breeding technologies have provided new cultivars of canola and pea that can diversify system agronomics Pan et al.Win-Win Scenarios for Farm and Climate and markets. These agronomic improvements require associated shifts in prescriptive, precision N and weed management. The integrated cfBMP systems we describe have the potential for reducing system-wide greenhouse gas (GHG) emissions by increasing soil C storage, N use efficiency (NUE) and by production of biofuels. Novel systems, even if they are economically competitive, can come with increased financial risk to producers, necessitating government support (e.g., subsidized crop insurance) to promote adoption. Other conservation-and climate change-targeted farm policies can also improve adoption. Ultimately, farmers must meet their economic and legacy goals to assure longer-term adoption of mature cfBMP for iPNW production systems.

Core Ideas Use of a stripper header to leave tall stubble for high‐residue no‐till. Winter triticale outperforms winter wheat in low rainfall dryland production. Tall crop residue reduces wind speeds at the soil surface. The low‐rainfall wheat production zone of eastern Washington is subject to wind erosion because of fine‐textured soils, low soil organic matter content, and tillage‐based winter wheat–summer fallow practices. Annual no‐till spring cropping systems to replace the low‐residue, erosive summer‐fallow period have not been economical. We conducted a 4‐year study at Ralston, WA to evaluate winter triticale (× Triticosecale) and non‐semi‐dwarf winter wheat (Triticum aestivum) biomass production, yield, nutrient use efficiency, and seed‐zone soil moisture during no‐till fallow and establishment of fall‐seeded canola. Treatments included winter triticale and winter wheat, both harvested with either a stripper header or conventional cutter‐bar header. Winter triticale produced more grain per pound of N fertilizer and per inch of soil water available than winter wheat, and overall yield was 30–80% greater than that of winter wheat. Full‐height cereals produced 20–90% more biomass than semi‐dwarf winter wheat. Stripper‐header triticale stubble maintained with no‐till chemical fallow (NTCF) reduced average wind speed at the soil surface to less than one‐half of the average wind speed recorded over reduced‐tillage winter wheat fallow. Soil moisture in the 0‐ to 3‐inch seed zone was greater and more uniform in stripper‐header no‐till fallow than in reduced‐tillage fallow. Maintenance of soil moisture by stripper‐header standing stubble was conducive to timely planting and establishment of fall‐seeded canola and led to greater crop establishment in no‐till fallow. Growing a high‐biomass cereal crop such as winter triticale or standard‐height winter wheat and harvesting with a stripper header produces a high‐residue, no‐till fallow that is a viable alternative to the traditional winter wheat–fallow cropping system.

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