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In this paper, we estimated using the machine learning methodology the main wetting branch of the soil water retention curve based on the knowledge of the main drying branch and other, optional, basic soil characteristics (particle size distribution, bulk density, organic matter content, or soil specific surface). The support vector machine algorithm was used for the models' development. The data needed by this algorithm for model training and validation consisted of 104 different undisturbed soil core samples collected from the topsoil layer (A horizon) of different soil profiles in Poland. The main wetting and drying branches of SWRC, as well as other basic soil physical characteristics, were determined for all soil samples. Models relying on different sets of input parameters were developed and validated. The analysis showed that taking into account other input parameters (i.e., particle size distribution, bulk density, organic matter content, or soil specific surface) than information about the drying branch of the SWRC has essentially no impact on the models' estimations. Developed models are validated and compared with well-known models that can be used for the same purpose, such as the Mualem (1977) (M77) and Kool and Parker (1987) (KP87) models. The developed models estimate the main wetting SWRC branch with estimation errors (RMSE = 0.018 m3/m3) that are significantly lower than those for the M77 (RMSE = 0.025 m3/m3) or KP87 (RMSE = 0. 047 m3/m3) models.

This paper presents the results of a survey conducted electronically in the years 2020-2022 within the framework of the AGRICORE Horizon project. It concerned the Agri-Environment-Climate Measure M10 within the Rural Development Programme 2014-2020 and aimed to quantify the impact of its effects on environmental and climatic policy implementation at a national level according to the perceptions of Polish farmers. The representativeness of the scrutinized population was checked using general data from the Polish Statistics Office. The results of our study show a positive perception of M10 by the participating farmers. The majority of them observed the income progress of their activities despite the increased workload connected with programme implementation and the increased costs associated with some of the declared activities. The innovation activities of the M10 participants were directed mainly at sustainable agriculture and protecting the environment. The respondents who did not decide to participate in M10 most frequently explained themselves by noting a lack of information about the programme, bureaucratic limitations, or doubts concerning the profitability of participation. The results of the study suggest that during the implementation of future EU agri-environmental measures, more attention should be paid to administrative and legal activities at the national level which may improve the perception of the programme. [ABSTRACT FROM AUTHOR]

The soil water retention curve (SWRC) is a key soil property required for predicting basic hydrological processes. SWRC is often obtained in laboratory with non-harmonized methods. Moreover, procedures associated to each method are not standardized. This can induce a lack of reproducibility between laboratories using different methods and procedures or using the same methods with different procedures. The goal of this study was to estimate the inter/intralaboratory variability of the measurement of the wet part (from 10 to 300 hPa) of the SWRC. An interlaboratory comparison was conducted between 14 laboratories, using artificially constructed, porous and structured samples as references. The bulk densities of samples were different at the very beginning of the experiment. This resulted in a variability of retention properties between the samples, which was estimated by a linear mixed model with a 'sample' random effect. Our estimate of inter/intralaboratory variability was therefore not affected by intrinsic differences between samples. The greatest portion of the differences in the measurement of SWRCs was due to interlaboratory variability. The intralaboratory variability was highly variable depending on the laboratory. Some laboratories successfully reproduced the same SWRC on the same sample, while others did not. The mean intralaboratory variability over all laboratories was smaller than the mean interlaboratory variability. A possible explanation for these results is that all laboratories used slightly different methods and procedures. We believe that this result may be of great importance regarding the quality of SWRC databases built by pooling SWRCs obtained in different laboratories. The quality of pedotransfer functions or maps that might be derived is probably hampered by this inter-/intralaboratory variability. The way forward is that measurement procedures of the SWRC need to be harmonized and standardized. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the dynamics of fluid topology during drainage and evaporation of wetting and non-wetting fluids via evaluation of their Euler characteristic (EC) and Betti numbers from designed experiments. The results showed that the EC of the non-wetting fluid remained constant at a high wetting fluid saturation and then decreased nonlinearly. However, the EC of the wetting fluid exhibited more complex trends. In the 2-D micromodel, the number of loops decreased monotonously, reached zero, and remained constant for lower saturations, while the number of distinct components fluctuated because of the appearance and disappearance of disconnected clusters. In the 2-D model, the number of distinct components played a significant role; in the 3-D X-ray CT experiment, the number of loops of pendular rings dominated the EC. The findings suggest that the trends observed in the 2-D micromodel may not apply under 3-D conditions. [ABSTRACT FROM AUTHOR]

This paper analyses the effects of soil macropores, temperature and water content on soil carbon dioxide (CO2) efflux behaviour, which could help understand the mechanism of CO2 efflux as influenced by soil type and land use methods. The temporal dynamic changes of CO2 efflux from the soil surface using a closed chamber method (LI-COR LI-8100A Automated Soil CO2 Flux System) were measured. Soil CO2 efflux was investigated at a topsoil depth of 0-5 cm in (1) arable land under conventional tillage on Cambisol (CM), (2) grassland on Cambisol, (3) park on Cambisol, (4) arable land under conventional tillage on Retisol (RT), (5) grassland on Retisol and (6) forest on Retisol. CO2 emission was measured six times per growing season from May to September in 2017. Soil macropore network was researched by implementing an X-ray computed tomography and carried out at the laboratory of the Institute of Agrophysics, Polish Academy of Sciences in Lublin, Poland. Macropores resulting from soil pedogenesis and land use methods played an important role on soil water, temperature and gas transport. The type of soil vegetation cover and amount of soil macropores significantly influenced soil respiration rate. The efflux values were recorded ranging from 0.71 to 3.43 µmol CO2 m-2 s-1 (Cambisol) and from 0.70 to 3.05 µmol CO2 m-2 s-1 (Retisol) in the grassland, from 0.43 to 2.57 µmol CO2 m-2 s-1 (Cambisol) in the park, from 0.44 to 2.52 µmol CO2 m-2 s-1 (Retisol) in the forest, from 0.52 to 2.68 µmol CO2 m-2 s-1 (Retisol) and from 0.09 to1.57 µmol CO2 m-2 s-1 (Cambisol) in the conventional tillage. Computational tomography data revealed that the content of macropores amounted to 10.75% in the grassland site, 1.97% in the park and 1.21% in the conventional tillage within the soil depth of 3-8 cm of the Cambisol and 6.45% in the forest, 4.94% in the conventional tillage and 3.86% in the grassland at the same soil depth of the Retisol. Soil temperature, water content and macroporosity were the main factors exerting the influence on soil gas origination rate. The relationship between soil CO2 efflux and volumetric water content at a 5 cm depth can be described by a linear regression model y = 0.0943x - 0.7651, R² = 0.53 (valid for volumetric water content from 22.5 to 27.0 vol.% on Retisol and from 16.8 to 24.4 vol.% on Cambisol). Also, linear regression model y = 0.1167x - 0.8214, R² = 0.65 showed the relationship between soil CO2 efflux and soil macroporosity at the 3-8 cm depth. Soil CO2 efflux displayed a typical polynomial relationship with soil temperature at the 5 cm depth; however, the relationship was very weak. Both soil type and land use methods had a noticeable influence on macroporosity, surface area and macropore range of soil pore-size distribution. The amount of macropores in macropore geometry was an important factor when dealing with CO2 flow. Topsoil CO2 efflux under contrasting vegetation cover and management conditions on Cambisol and Retisol was directly related to soil macroporosity and volumetric water content. [ABSTRACT FROM AUTHOR]