Planned versus Actual Outcomes As a Result of Animal Feeding Operation Decisions for Managing Phosphorus

Abstract

The paper explores how decisions made on animal feeding operations (AFOs) influence the management of manure and phosphorus. Variability among these decisions from operation to operation and from field to field can influence the validity of nutrient loss risk assessments. These assessments are based on assumptions that the decision outcomes regarding manure distribution will occur as they are planned. The discrepancy between planned versus actual outcomes in phosphorus management was explored on nine AFOs managing a contiguous set of 210 fields in south-central Wisconsin. A total of 2611 soil samples were collected and multiple interviews conducted to assign phosphorus index (PI) ratings to the fields. Spearman's rank correlation coefficients (r(S)) indicated that PI ratings were less sensitive to soil test phosphorus (STP) levels (r(S) = 0.378), universal soil loss equation (USLE) (r(S) = 0.261), ratings for chemical fertilizer application (r(S) = 0.185), and runoff class (r(S) = -0.089), and more sensitive to ratings for manure application (r(S) = 0.854). One-way ANOVA indicated that mean field STP levels were more homogenous than field PI ratings between AFOs. Kolmogorov-Smirnov (K-S) tests displayed several nonsignificant comparisons for cumulative distribution functions, S(x), of mean STP levels on AFO fields. On the other hand, the K-S tests of S(x) for PI ratings indicated that the majority of these S(x) functions were significantly different between AFOs at or greater than the 0.05 significance level. Interviews suggested multiple reasons for divergence between planned and actual outcomes in managing phosphorus, and that this divergence arises at the strategic, tactical, and operational levels of decision-making.

Factors Affecting Manure Applications as Directed by Nutrient Management Plans at Four Connecticut Dairy Farms

“…The differences were mainly a result of better knowledge about the nutrient status of the fields obtained by creation of the first individual field records containing detailed information about the fields including: soil type, slope, nearness to water bodies, previous fertilizer and manure applications, the soil test status of the fields, etc. Whether farmers implement the recommendations is a matter of choice that can be affected by many factors (Beegle et al, 2000; Cabot and Nowak, 2005) and can be analyzed using econometric techniques. Probit models for panel data were used to calculate the probability of excess application of manure P compared with recommended amounts of manure P in the NMP.…”

“…Studies have shown that implementing NMPs requires farmers to change their management of the farm at the strategic, tactical, and operational levels (Beegle et al, 2000; Cabot and Nowak, 2005; Tao et al, 2010). The factors that contribute to the likelihood of implementation by farmers include: (i) farm characteristics such as farm size and farm type (Halstead et al, 1990; Paudel et al, 2008); (ii) farmer characteristics such as age, education, attitude toward environmental concerns, contact with extension, and attitude toward new programs (Horan and Ribaudo, 1999; Nkamleu and Adesina, 2000); (iii) farm business characteristics and socioeconomic factors such as tenure and farm income, credit, and debt (Kim et al, 2005; Nkamleu and Adesina, 2000; Rahelizatovo and Gillespie, 2004; Smit and Smithers, 1992); and (iv) applicability of the NMPs to a given farm (Bosch et al, 1995; Diep and Beaulieu, 2005; Fuglie and Kascak, 2001; Hidsley, 2002; Paudel et al, 2008).…”

Disproportionality as a Framework for Linking Social and Biophysical Systems

“…Nine of the 10 commercial farms in the watershed study area allowed researchers on their fields to obtain soil samples based on a 1-ha sampling grid (Cabot and Nowak 2005). In total, 3410 environmental soil samples (i.e., 5-cm samples using Bray 1 protocols) were taken across the 217 fields (1267 ha) managed by these farms in the watershed.…”

Nutrient Applications Reported by Farmers Compared with Performance‐Based Nutrient Management Plans

“…Application of recommended amounts of nutrients from manure is difficult for farmers. Numerous tactical and operational factors, such as weather, machinery constraints, and the cultural preferences of farmers can substantially change the amount of nutrients applied from the amount recommended in the NMP (Cabot and Nowak, 2005). In the absence of penalties, farmers tend to distribute manure to the nearby fields at rates that provide excess nutrients, mainly N and P, to crops (Innes, 2000).…”