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Repetitive use of heavy farm machinery in cultivated agriculture may cause soil compaction that can adversely affect soil‐health‐related properties. Cover crops (CC) are well‐documented to alleviate problems associated with compaction and improve overall soil health in time. The objective of this field study was to evaluate the cumulative effects of CC treatment (i.e., with ≥ 6 years cereal rye [Secale cereale L.] CC and ≥ 4 years with no cover crop [NCC]) and sample/measurement placement (i.e., in the bed [B] and in the wheel‐track [WT] and no‐wheel‐track [NWT] furrow) on near‐surface soil physical‐, chemical‐, and infiltration‐related properties in an alluvial soil under cotton (Gossypium hirsutum L.) production in the Lower Mississippi River Valley. Samples were collected and in‐situ measurements were conducted in late May 2019 within a single field in eastern Arkansas. Overall‐infiltration rate was two times greater (p ≤ 0.01) in B compared to WT and NWT placement, which did not differ. Soil bulk density in WT was 1.1 times greater than the other two placements, while soil organic matter was greater in CC‐WT (30.7 Mg ha−1) than in all other treatment‐placement combinations, except for CC‐NWT, which did not differ. Similarly, water‐stable‐aggregate concentration was 2.3 and 1.6 times greater in the CC‐NWT and CC‐WT combinations, respectively, which did not differ, compared to under NCC. Results demonstrated that CC benefits extended beyond the bed to positively affect soil properties in adjacent WT and NWT furrows. Continued small‐scale, long‐term management studies using CC will extend insight into site‐specific, soil‐health improvements. Core Ideas: Cover crop use in cotton production reduced compaction and improved soil health in eastern Arkansas.Soil bulk density was greater in wheel‐track than in the bed and no‐wheel‐track placements.Soil organic matter was greatest in cover crop‐wheel and no‐wheel track treatment‐placement combinations.Wheel‐ and no‐wheel‐track water‐stable aggregation was greater in cover than no‐cover treatments. [ABSTRACT FROM AUTHOR]

Phosphorus (P) can be recovered from wastewater and used as an alternative fertilizer, namely, struvite [MgNH4PO4·6(H2O)]. However, the soil mobility of wastewater‐derived P and other nutrients needs to be evaluated. The objective of this study was to compare the vertical distribution of water‐soluble (WS) soil P and other nutrients from a synthetic‐wastewater‐derived electrochemically precipitated struvite (ECST) to that from a chemically precipitated struvite (CPST), triple superphosphate (TSP), monoammonium phosphate (MAP), and a control in six soils from Arkansas (AR; loam [L] and silt loam [SiL]), Missouri (MO; SiL 1 and SiL 2), and Nebraska (NE; sandy loam [SL] and SiL). A column‐leaching experiment was conducted with the six soils and five fertilizer‐P treatments. Water‐soluble (WS) P from the two struvite materials generally did not differ (p > 0.05) and was similar to that of MAP in the depths of 0–3, 3–6, and 6–10 cm, but was greater than that of TSP in the top 6 cm in four of the six soils. WS P from CPST in the MO‐SiL 2 and NE‐SL soils (6.6 and 12.7 mg kg−1, respectively) was larger than that from ECST, MAP, and TSP. In the AR‐L and MO‐SiL 1 soils, TSP was the only fertilizer‐P source that had increased WS P concentrations in the top 6 cm relative to the other fertilizer‐P sources. Results showed that ECST‐derived, WS P had similar soil profile distributions in the top 10 cm, suggesting that ECST will be equally protective of environmental health and leachate quality across multiple soil textures as other common fertilizer‐P sources. Core Ideas: Soil P from electrochemically precipitated struvite is not more mobile than that from other P fertilizers.Near‐surface soil pH and nutrient distributions are similar between struvite and other P fertilizers.Struvite appears to behave similar to other common fertilizer‐P sources across multiple soil textures. [ABSTRACT FROM AUTHOR]

Phosphate‐rich struvite (MgNH4PO4·6H2O) can be reclaimed from wastewater as a fertilizer material to help provide clean water and sustainable food production. The objective of this study was to evaluate the leaching characteristics of wastewater‐recovered electrochemically precipitated struvite (ECST) compared to other common fertilizer‐P sources in soils from Arkansas (AR loam and silt loam), Missouri (MO silt loam 1 and 2), and Nebraska (NE sandy loam and silt loam). A bench‐scale, soil‐column experiment was conducted using five fertilizer‐P sources (i.e., ECST, chemically precipitated struvite [CPST], monoammonium phosphate [MAP], triple superphosphate [TSP], and an unamended control [UC]) and leached six times over 15 weeks after fertilizer application. Leachate‐P concentration changes from the UC differed among soil–fertilizer combinations over time (p < 0.05) but only in the AR‐loam, where TSP (2.0–6.6 mg L−1) consistently had a larger leachate‐P change from the UC than ECST (−0.04 to 3.1 mg L−1) in weeks 1–3. Leachate‐NO3‐N concentration changes from the UC among soils occurred only in week 1, where three of the six soils had NO3‐N concentration increases >10.7 mg L−1 from their respective UC. Though inconsistent across the various soils evaluated, P‐leaching losses relative to respective UC treatments were often larger from MAP and TSP than ECST and CPST. Results showed that P, NH4‐N, NO3‐N, Ca, Mg, and Fe leaching potentials differed among soils depending on initial soil pH and texture and fertilizer‐P source; thus, soil characteristics and fertilizer‐P source should be considered to minimize potential nutrient leaching losses. Core Ideas: Phosphorus and nitrogen can be recovered from synthetic wastewater via electrochemical precipitation.Nutrient leaching from electrochemically precipitated struvite is comparable to other phosphorus fertilizers.Electrochemically precipitated struvite appears to be a viable alternative phosphorus fertilizer across textures. [ABSTRACT FROM AUTHOR]