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California farmers who use reduced-disturbance tillage and winter cover cropping can boost production and improve soil health. However, some farmers are hesitant to try these conservation practices due to uncertainty about whether planting winter cover crops will deplete soil moisture in already drought-stricken regions. Our study addresses these concerns by looking at how long-term reduced-disturbance tillage and winter cover cropping, compared to fallowed soils with standard tillage, affected soil moisture. Although we found a statistical difference in total soil water content, the difference was only about 0.3 inches of water per foot of soil. On average, the soil water content of the top 0-96 inches was highest for the reduced-disturbance fields with winter cover crops. This was especially evident during our driest field season, from November 1, 2017, to March 15, 2018, when cumulative rainfall was only 1.9 inches. Our findings show that winter cover cropping and reduced-disturbance tillage can improve soil without depleting soil water levels in row crops. [ABSTRACT FROM AUTHOR]

The uncertainty of water resources availability is a growing problem in California as agricultural industrialization, population growth, and climate change affect water resources. The intense manipulation of the hydrological regime has led to the depletion of the water resources in the state and the subsequent use of various adaptive management strategies to cope with environmental conditions and social concerns. The historical imbalance between water pumping and replenishment in Pajaro Valley has led to overdrafted aquifers, seawater intrusion, and salinization. The objective of this study is to estimate the sustainable carrying capacity of agricultural land in Pajaro Valley while preventing groundwater overdraft. A groundwater box model was built and calibrated using historical data to represent current and future hydrology and water management strategies. An optimization model maximized the economic profit using the agricultural acreage as the decision variable with a set of constraints aimed at determining the sustainable carrying capacity of the groundwater basin. Model constraints include total land and water availability, crop acreage, agricultural water use, and historical demand. In the Pajaro Valley, agricultural operations must use less water more efficiently, which means changes in crop types, size of activities, and fallowing land in parts of the basin. Results of the optimal scenario over 25 years show a 15% reduction of total agricultural acreage, 8.5% reduction in food production, average profit loss of 4%, and a 79% reduction in aquifer depletion. This study provides an overall vision of what can be accomplished with coordinated land use planning using strategies that harmonize individual decisions and shared natural resources. [ABSTRACT FROM AUTHOR]

Management of agricultural irrigation water is extremely important as fresh water resources are being depleted on a global scale. In anticipation of regulatory restrictions, several greenhouse and nursery operations in New Jersey have implemented systems that disinfect and recycle their irrigation water. This study compared the disinfection methods at two greenhouses and three container nurseries, focusing on the qualitative and quantitative benefits of using chlorine gas, ultraviolet light, ozone, and copper for water disinfection. The data were collected during on-site visits where the growers were interviewed on camera. A cost analysis was performed, but the most efficient disinfection technique could not be determined due to the variability between businesses and various unquantifiable benefits of proactive water management recycling, such as improved plant health, decreased fungicide and fertilizer use, a cleaner operation, reduced runoff, reduced pressure on aquifers, and increased customer satisfaction. The investment and maintenance costs per hectare and 1000 L were calculated, which can be useful reference tools for growers. The net present value (NPV) of each disinfection system was calculated to analyze the profitability of the investments. All three container nurseries had positive NPV values and profitable investments, which improved with cost sharing from the National Resource Conservation Service. This information will be useful in the future as growers throughout the state, and country, may be required to deal with the stricter regulation of their irrigation runoff. [ABSTRACT FROM AUTHOR]

Winter cover crops could contribute to more sustainable agricultural production and increase resiliency to climate change; however, their adoption remains low in California. This paper seeks to understand barriers to winter cover crop adoption by monetizing their long-term economic and agronomic impacts on farm profitability in two of California's specialty crop systems: processing tomatoes and almonds. Our modeling effort provides a present, discounted valuation of the long-term use of winter cover crops through a cost-benefit analysis. A net present value model estimates the cumulative economic value of this practice. We then explore how the long-term trade-offs associated with winter cover crops can affect an operation's profits under a spectrum of hypothetical changes in California's agricultural landscape. Our analysis sheds light on the barriers to adoption by reporting benefit-cost ratios that indicate profitability across several scenarios; however, benefits and costs accrue differently over time and with long planning horizons. At the same time, a small portion of gained benefits are external to the grower. Findings from this study reveal that winter cover crops in California can be profitable in the long-term, but the extent of profit depends on the cropping system, extent of irrigation savings due to improved soil function, access to financial subsidies and climate change. Winter cover crops can return positive net benefits to growers who have flexible contractual obligations, can wait for the long-term return on investment and manage cover crops as closely as cash crops. This analysis contributes to the study of conservation agriculture practices by explaining possible reasons for low adoption through an economic valuation of the implications of soil management choices and policy counterfactuals. • Net present value models were used to understand winter cover crop adoption in California. • Winter cover cropping can increase baseline profits in specialty crop systems sometimes. • The value of winter cover crops accrues over many planting seasons. • Reduced irrigation and increased subsidies can increase adoption of cover crops. [ABSTRACT FROM AUTHOR]

Greenhouse growers find themselves under increasing pressure to respond to consumer preferences to use environmentally sustainable practices and materials while maintaining profitable operations. These consumer preferences reflect a mounting awareness of the environmental issues, such as climate change and their associated social costs. Ideally, sustainable horticultural production accounts for both traditional economic considerations and such social costs, some of which can be explained through the calculation of global warming potential (GWP). An obvious candidate for a sustainable intervention is the traditional plastic pot, which growers can replace with alternative biocontainers with varying degrees of GWP. This study calculates the variability of direct costs of production using alternative containers to offer a comparison of social and economic costs. We evaluated these direct costs of producing petunia (Petunia3hybrida) grown in pots made of traditional plastic, bioplastic, coir, manure, peat, bioplastic sleeve, slotted rice hull, solid rice hull, straw, wood fiber, and recycled reground plastic containers used in a previous assessment of GWP. Our analysis of the costs when using a traditional plastic pot showed that the highest contributors to GWP were different from the highest contributors to direct costs, revealing that the price does not reflect the environmental impact of several inputs. Electricity, the plastic shuttle tray, and the plastic pot contributed most to GWP, whereas labor, the plastic container, and paclobutrozol growth regulator contributed most to direct cost of production (COP). At 64% of total cost, labor was the most expensive input. Watering by hand added another $0.37-$0.54 per plant in labor. When we analyzed input costs of each alternative container separately, container type had the largest impact on total direct costs. Before adding container costs, the direct COP ranged from $0.56 to $0.61 per plant. After adding containers, costs ranged from $0.61 to $0.97 per plant. Wood fiber pots were the most expensive and recycled reground plastic pots were the least expensive in this study. Based on our assessment and the observed small variation in GWP between alternative containers, growers would benefit from selecting a container based on price and consumer demand. Some social costs that we are not aware of yet may be associated with some or all biocontainers. [ABSTRACT FROM AUTHOR]