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Full inversion tillage (FIT) at pasture renewal is a management option aiming to increase carbon stocks in long-term pasture, to achieve carbon neutrality. This study investigated the effects of FIT on carbon and nutrient distribution in the soil profile (0–7.5, 7.5–15, 15–22.5 and 22.5–30 cm depths) as well as nutrient uptake, and subsequent fodder crop and/or pasture yields across three pasture renewal trials (Trials 1 and 3: Alfisol; Trial 2: Andisol). These effects of FIT were assessed against standard tillage treatments (no till, shallow till), and non-renewed pasture within 8–18 months post-tillage. FIT changed soil carbon stratification, causing 16%–46% reduction in topsoil (0–7.5 cm) cation exchange capacity across the three trials. However, nutrient levels after FIT remained within recommended ranges for crop and/or pasture growth, avoiding any yield reductions. Topsoil fertility post-FIT depended on original degree of nutrient stratification in the soil profile. At Trial 1, temporary deficiencies caused by low subsoil P and K soil tests pre-FIT were anticipated and corrected with fertiliser nutrients for the following break crop and resown pasture. We conclude that soil testing the cultivation depth prior to FIT at pasture renewal provides the necessary soil test information to manage yield expectations. [ABSTRACT FROM AUTHOR]

The objective of this laboratory incubation study was to assess the effectiveness and longevity of urease inhibitor N-(2-nitrophenyl) phosphoric triamide (2-NPT), along with the commonly used N-(n-butyl) thiophosphoric triamide (nBTPT), in reducing ammonia (N[H.sub.3]) emissions from cattle urine applied to pasture soils. It was hypothesised that 2-NPT would be effective as a longer-lasting inhibitor to reduce emissions after the deposition of urine during multiple grazing events. Two dairy-grazed pasture soils (Fluvisol, Rangitikei loamy sand (RLS) and Andosol, Egmont black loam (EBL)) with contrasting organic carbon levels and urease activity were used. The following treatments were applied to the soils at the start of the experiment: no inhibitor, nBTPT-low, 2-NPT-low, 2-NPT-medium and 2-NPT-high. Urine-N was applied to all the treatments at four stages: immediately before inhibitor application (Stage A), 29 days after inhibitor application (Stage B), 56 days after inhibitor application (Stage C) and 29 days and again 60 days after inhibitor application (Stage D); N[H.sub.3] emissions were measured up to Day 31 after each urine application. The low, medium and high application rates of inhibitors were determined based on achieving 0.025%, 0.050% and 0.075% of quantity of urine-N applied in Stage A respectively. For the no inhibitor treatment, the proportion of total applied N in urine that was emitted as N[H.sub.3] for the different stages ranged from 35.8% to 50.5% for RLS soil and from 14.2% to 26.7% for EBL soil. For Stage A, both inhibitors equally reduced N[H.sub.3] emissions from applied urine in both soils (23.7-27.3% for the RLS and 20.6-27.2% for the EBL). For Stage B, significant reductions (4.2-13.4%) in N[H.sub.3] emitted was observed only from RLS soil, with there being a significantly greater reduction from 2-NPT than from nBTPT, and 2-NPT continued to reduce N[H.sub.3] emissions at Stage C (5.6-7.4%). There was no reduction in emissions during Stage D by either of the inhibitors. The results of this study suggest that 2-NPT can extend the longevity of urease inhibition and reduce N[H.sub.3] emissions compared with the more commonly used inhibitor nBTPT in dairy-grazed pasture soils. Additional keywords: dairy soils, environmental degradation, nitrogen loss, nitrogen use efficiency, soil pH, urea hydrolysis. Received 11 November 2018, accepted 31 May 2019, published online 23 July 2019, Introduction The intensification and expansion of dairy farming in New Zealand (NZ) over the past three decades has resulted in a significant rise in the amount of cattle urine being [...]

Micronutrients copper (Cu) and zinc (Zn) have the potential to inhibit soil urease activity (UA) and reduce ammonia (N[H.sub.3]) emissions over long duration (8-12 weeks) but have not been tested for reducing N[H.sub.3] losses from cattle urine deposited in dairy-grazed pasture soils. The objective of this study was to assess the effectiveness and longevity of Cu and Zn in reducing soil UA, for the use of these metals to reduce N[H.sub.3] emissions from deposited urine by grazing cattle. A series of experiments were conducted to (i) assess the relationship between inherent Cu and Zn status and soil UA of New Zealand dairy-grazed pasture soils, (ii) determine the impact of Cu and Zn addition to pasture soils on soil UA and (iii) investigate how soil organic carbon (C) and other C-related textural and mineralogical properties such as clay content and cation exchange capacity influence the effectiveness of added Cu and Zn in reducing urea hydrolysis. The results showed significant positive correlations of soil total C and total nitrogen (N) with soil UA. However, there were no significant negative correlations of soil UA with inherent Cu and Zn levels. Similarly, addition of Cu and Zn to soil did not significantly reduce soil UA. However, when Cu was added to two different soil supernatants there was a significant reduction in hydrolysis of urea applied at 120 and 600 mg urea-N [kg.sup.-1] soil. Additions of Zn achieved negligible or small reductions in urea hydrolysis after 120 and 600 mg urea-N [kg.sup.-1] soil applications to soil supernatants. This result suggests that Cu can inhibit soil UA and urea hydrolysis in soil supernatants with potentially low C, clay and cation exchangeable base contents. However, the interaction of bioavailable Cu with labile soil organic C and clay particles leads to its inactivation, resulting in ineffectiveness in organic C-rich pasture soils. Although most of the added Zn did not complex and remained bioavailable, the observed levels of bioavailable Zn had limited effect on soil UA. Additional keywords: ammonia emissions, clay content and cation exchange capacity, metal bioavailability, nitrogen loss, nitrogen use efficiency, soil organic carbon, urease inhibition., Introduction Intensification of dairy farming in New Zealand (NZ) over the last three decades has resulted in a substantial increase in the national dairy herd size from 2.3 million cows [...]

Plantain (Plantago lanceolata L.) is a forage that produces secondary metabolites with one, aucubin, known to inhibit soil nitrification. This study aimed to quantify the exudation of aucubin and catalpol by plantain root systems in a hydroponic experiment; evaluate the effect of aucubin on nitrogen (N) leaching and nitrous oxide (N2O) emissions from urine applied to plantain and ryegrass-white clover swards; and compare N losses from a ryegrass-white clover sward after urine from cows fed plantain and cows fed ryegrass-white clover was applied. Nitrate ( NO 3 − ) leaching and N2O losses were measured in a lysimeter experiment. Catalpol, but not aucubin, was exudated by plantain roots. N2O emissions were decreased by plantain swards and by ryegrass-white clover swards to which aucubin was also applied. Aucubin had no effect on NO 3 − leaching. Urine from cows grazing plantain had no effect on N2O emissions, and N leaching when compared to the urine from cows grazing ryegrass-white clover with the same N content. We conclude the plantain sward and the aucubin applied to the ryegrass-white clover sward decreased N2O emissions via mechanisms in the soil separate from the decreased emissions resulting from the lower N concentration of urine derived from cows grazing plantain. [ABSTRACT FROM AUTHOR]

Nitrification inhibitors can reduce nitrous oxide (N2O) emissions and nitrate leaching losses from agricultural soils. Technologies have been developed to detect and target urine patches for inhibitor application, thereby reducing the total amount of inhibitor used. However, in practice there will be a time delay between the urine deposition and inhibitor application, potentially leading to physical separation of the inhibitor and urine that could reduce the effectiveness of the inhibitor compared to when the inhibitor and urine are well mixed. In this study, 2L of cattle urine was applied on two soil types in New Zealand. Twenty-four hours later the inhibitor dicyandiamide (DCD) was applied. The soil was sampled within 18 h and again after a rainfall event. DCD concentrations were measured in the 0–20 mm, 20–50 mm, and 50–100 mm depth ranges. The movement of the urine in the soil was simulated using the HYDRUS model. Before the rain most of the DCD was within the top 20 mm and intercepted 21–29% of the urine. After the rainfall event the DCD concentration decreased in the 0–20 mm layer and increased in the 20–50 mm layer. 18–55% or 63-79% of the urine was intercepted by DCD at a concentration of >4 ppm using the measured and modelled DCD concentrations, respectively. However, only 0–27% or 0-53% of the urine was intercepted at a DCD concentration >10 ppm. [ABSTRACT FROM AUTHOR]

The annual quantities of nitrate-N (-N) and total N (TN) leached from mole and pipe drained dairy pastures on a Pallic soil, were reduced by an average of 52% and 42% (p < .05), respectively, by standing cows off pasture to ruminate and rest after grazing (Duration-controlled grazing, DC), compared to the standard grazing management (SG) of leaving cows at pasture between milkings. For the SG treatment, measured -N leached was 13, 8 and 21 kg N ha−1 and total N leached was 18, 13 and 26 kg N ha−1 in 2009, 2010 and 2011, respectively. Annual surface runoff contained <1 kg -N ha−1 y−1 and <3 kg TN ha−1 y−1. The deposition of urine in the autumn period had the greatest influence on the quantity of leached in winter drainage. DC grazing is a practical method to reduce N leaching from grazed dairy pastures. [ABSTRACT FROM AUTHOR]

Standing cows off pasture after 4 hours of grazing (duration-controlled (DC) grazing) was researched over 3 years (2008-2011) to compare the losses of nutrients in drainage and surface runoff water with losses under standard grazing (SG). Pasture growth rates, nutrient concentrations and apparent intake by cows were used to model nutrient removals from, and returns to, pasture. Pre- and post-grazing covers and apparent pasture intakes were similar for both treatments. Quantities of N, P and K returned to the DC plots in excreta and effluent were 34%, 0% and 45% less than those returned to SG plots. This reduction in nutrient returns was associated with a nil, 20% and 9% decrease in annual pasture growth on the DC plots in the three respective years. Reductions in annual pasture growth under DC grazing may be avoidable if nutrient removals are balanced with returns in effluent and fertiliser. [ABSTRACT FROM AUTHOR]

To assist the adoption of biochar production as a greenhouse gas mitigation technology, evidence is required that biochar can provide additional economic benefits covering its current cost of manufacture. Biochar has the potential to be used as sorbent for NH4+-N removal from wastewaters. Two batch studies were conducted to compare (i) sorption of NH4+-N on pine biochars with different particle sizes and (ii) sorption of NH4+-N on pine biochar in comparison to alternative sorbents, zeolite (clinoptilolite) and pine bark. Decreasing the particle size of the feedstock (pine chip), or the biochar by crushing after pyrolysis, did not affect its NH4+-N sorption properties. Sorption of NH4+-N on comparative sorbents, when added at a dose of 39 mg NH4+-N L−1, followed the order zeolite > biochar > bark. Zeolite proved to be the most efficient sorbent for NH4+-N g−1 removal followed by biochar and bark. Biochar has the potential to be used as a cost effective commercial sorbent for removing NH4+-N from waste streams. [ABSTRACT FROM AUTHOR]

We here analyze the factor loadings given by the CAPM, the Fama–French three (FF3), and the five-factor model (FF5), and test the performance and the validity of adding two more factors (volatility and dispersion of returns) to the FF5 factor model of European index-based ESG leaders' portfolios. Our ESG leaders' portfolios generated significant negative alphas during 2012–2022, corroborating the literature's negative argument. The negative abnormal returns of ESG leaders' portfolios are homogeneous across the three ESG pillars. We conclude that European ESG leaders' portfolios are biased toward large cap and value stocks with robust operating profitability and against aggressive investments. As robustness tests, we examine Global ESG leaders' index-based portfolios, producing the same results but with reduced importance in some loading factors like profitability and investment strategy. Furthermore, we deduced that European and Global ESG leaders' portfolios tilt towards volatility and herding bias. [ABSTRACT FROM AUTHOR]