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Winemaking in Chile is a long tradition that is recognized around the world. It is especially important in the Maule region where more than 40% of the total wine in the country is produced. However, there is a lack of studies related to soil erosion in vineyards in Chile, especially considering the extreme rainfall events that occur in the country. This research estimates soil erosion mobilization rates before and after a rainy season between April 2020 and May 2020 using the "improved stock unearthing method" on two inter‐row plots in a vineyard located in the Maule region of Chile. This method relies on the graft union as a bioindicator for assessing soil surface‐level changes. Maps of the soil surface were obtained to show how soil depletion and accumulation points within the inter‐row areas could be detected. It has been estimated that a total soil mobilization of 85.7 and 130 Mg ha yr−1 had occurred in the inter‐row areas 1 and 2, respectively, since the establishment of the plantation. However, a single rain event mobilized soil at rates of 5.5 and 3.5 Mg ha yr−1, respectively, in the inter‐row areas 1 and 2. We have demonstrated that erosive processes present in the study area exceed the rates of soil formation and the tolerable rates of erosion on a global scale. The results allow re‐thinking of agricultural practices and management of soil systems to improve the sustainability of conventional Chilean vineyards and their soils. [ABSTRACT FROM AUTHOR]

The intensification of specific land management operations (tillage, herbicide, etc.) is increasing land degradation and contributing to ecosystem pollution. Mulches can be a sustainable tool to counter these processes. This is particularly relevant for rural areas in low-income countries where agriculture is a vital sector. In this research, the environmental impact of different rates of wheat residues (no residues, 25, 50, 75, and 100%) in corn silage cultivation was evaluated using the life cycle assessment (LCA) method under conventional tillage (CT) and no-tillage (NT) systems in a semi-arid region in Karaj, Iran. Results showed that in both tillage systems, marine aquatic ecotoxicity (ME) and global warming potential (GWP) had the highest levels of pollution among the environmental impact indicators. In CT systems, the minimum (17,730.70 kg 1,4-dichlorobenzene (DB) eq.) and maximum (33,683.97 kg 1,4-DB eq.) amounts of ME were related to 0 and 100% wheat residue rates, respectively. Also, in the CT system, 0 and 100% wheat residue rates resulted in minimum (176.72 kg CO2 eq.) and maximum (324.95 kg CO2 eq.) amounts of GWP, respectively. However, in the NT system, the 100% wheat residue rate showed the minimum amounts of ME (11,442.39 kg 1,4-DB eq.) and GWP (120.21 kg CO2 eq.). Also, in the NT system, maximum amounts of ME (17,174 kg 1,4-DB eq.) and GWP (175.60 kg CO2 eq.) were observed with a zero wheat residue rate. On-farm emissions and nitrogen fertilizers were the two factors with the highest contribution to the degradation related to environmental parameters at all rates of wheat residues. Moreover, in the CT system, the number of environmental pollutants increased with the addition of a higher wheat residue rate, while in the NT system, increasing residue rates decreased the amount of environmental pollutants. In conclusion, this LCA demonstrates that the NT system with the full retention of wheat residues (100%) is a more environmentally sustainable practice for corn silage production. Therefore, it may be considered one of the most adequate management strategies in this region and similar semi-arid conditions. Further long-term research and considering more environmental impact categories are required to assess the real potential of crop residues and tillage management for sustainable corn silage production. [ABSTRACT FROM AUTHOR]

• Design and build heat-pulse probe based on transient state technology to measure λ. • Positive correlations between λ and estimates from a pedotransfer function. • Conventional tillage increases temperature flow in soils because of decreasing ρb. • The proposed HPP is a low-cost and energy-efficient device with wide applicability. Accurate soil thermal conductivity (λ) measurements are needed in experimental agri-environmental research. This study design and build of new heat-pulse probe (HPP) based on transient state technology to measure λ. The HPP consists of three main components: an electronic control system, a measurement chamber, and sample rings. The performance of the new HPP for in-situ λ measurements is compared to estimates from measurable soil physical properties (pedotransfer function). Tests were conducted in clay loam and loam soils at three depths. λ measurements by the HPP were affected by tillage practice, fertilizer treatment, soil depth, and soil type. No significant differences in λ measurements by the HPP and estimates from a pedotransfer function were found between tillage practices. There were positive correlations between their values at three soil depths: R 2 = 0.92 at 0–5 cm depth, and R 2 = 0.88 at both 5–10 and 10–15 cm depths. The standard deviation from the HPP measurements were 0.061, 0.077, and 0.080 W·m−1·K−1 at 0–5, 5–10, and 10–15 cm depths, respectively. In contrast, the pedotransfer function estimates had standard deviations of 0.085, 0.660, and 0.083 W·m−1·K−1, respectively. It was found that conventional tillage increases temperature flow in soils compared to no-tillage because of decreasing soil bulk density (ρb) and consequently higher porosity. The proposed HPP is a low-cost and energy-efficient device, with wide applicability under a range of conditions. It is highly recommended for measuring λ clay loam and loam soils; however, more research is needed to determine its value with other soil types. [ABSTRACT FROM AUTHOR]

Appropriate management of crop residue plays a key role in mitigating greenhouse gas emissions. However, it has been inadequately implemented in general agricultural management practices. In a field investigation using static chambers, we evaluated the effects of crop residue at three different rates - 100 % (R 100), 50 % (R 50), and residue removal (R 0) - on carbon dioxide (CO 2) efflux. The field study was conducted in corn-wheat rotation under conventional (CT) and no-tillage (NT) systems in a semi-arid region. The main results showed that CO 2 efflux was positively correlated with higher soil temperature (0.43–0.79) and microbial biomass carbon (0.66–0.89). The crop residue treatments affected these traits. A strong positive relationship between CO 2 efflux and the crop residue (R2 = 0.96, CT and R2 = 0.9 for NT) was observed. In the CT system, significant increases were detected among residue rates on cumulative CO 2 efflux, where R 100 and R 50 resulted in 36 % and 25 % higher cumulative CO 2 efflux, respectively, than R 0. In contrast, there was no significant difference in cumulative CO 2 efflux among the crop residue retention (R 100 and R 50) and removal (R 0) treatments under the NT system. Our study revealed that crop residue retention led to increased CO 2 efflux under the CT system in semi-arid conditions during the first year of application, while under the NT system, CO 2 efflux was not impacted by crop residue. Our results indicate that there is considerable potential for improving soil management practices in the context of soil degradation, climate change, increasing crop productivity, and carbon (C) sequestration. • CO 2 emissions are correlated with soil temperature and microbial biomass carbon as well as with crop residue. The crop residue treatments affect these traits. • Full retention of crop residue mitigates CO 2 emissions under the no-tillage system. • The implementation of the results improves the conservation of soils' productivity, and fights climate change. [ABSTRACT FROM AUTHOR]