Soil Systems

8 pages, 210 KiB

Open AccessArticle

Short-Term Effects of Cover Crops and Tillage Management on Soil Physical Properties on Silt Loam Soil

by D. Scott Patton, V. Steven Green, D. Keith Morris and Calvin R. Shumway

Soil Syst. 2024, 8(4), 122; https://doi.org/10.3390/soilsystems8040122 - 26 Nov 2024

Silt loam soils in the mid-southern United States are prone to soil erosion, crusting, and general soil degradation. A field experiment was established at three field sites in northeast Arkansas to evaluate the effect of cover crop and tillage management on cash crop [...] Read more.

Silt loam soils in the mid-southern United States are prone to soil erosion, crusting, and general soil degradation. A field experiment was established at three field sites in northeast Arkansas to evaluate the effect of cover crop and tillage management on cash crop yield and the physical properties of soil health, specifically infiltration rate and aggregate stability. Cover crop management included cereal rye, wheat and crimson clover, and a winter fallow. Tillage management included tillage and no-tillage. During the two-year study, yield was not significantly influenced by different tillage treatments. The cover crop treatment had greater yield than the no-cover crop treatment (5091 vs. 4264 kg ha⁻¹) at one site in one of the years. Water infiltration was significantly improved with cover crops compared to with no-cover crops, with a 52% and 64% increase at Walcott and Magnolia, respectively. Soil aggregate stability was significantly improved with no-tillage as compared with tillage in both years at Walcott, with a 16% and 58% increase in 2015 and 2016, respectively. Both cover crop and tillage management can have significant impacts on soil physical properties in a short period of time. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

15 pages, 3560 KiB

Open AccessArticle

The Effects of the Long-Term Application of Different Nitrogen Fertilizers on Brown Earth Fertility Indices and Fungal Communities

by Hui Li, Zishu Cai, Jiubo Pei, Mengmeng Wang, Siyin Wang, Yao Zhang and Yuwei Liu

Soil Syst. 2024, 8(4), 121; https://doi.org/10.3390/soilsystems8040121 - 21 Nov 2024

Viewed by 521

Abstract

Soil fungi play a crucial role in soil microbes, the composition and variety of whose communities can be altered due to nitrogen constraints, thereby affecting the plant’s development. This study aimed to investigate the relationship between the composition of soil fungi communities, fertility [...] Read more.

Soil fungi play a crucial role in soil microbes, the composition and variety of whose communities can be altered due to nitrogen constraints, thereby affecting the plant’s development. This study aimed to investigate the relationship between the composition of soil fungi communities, fertility index, and the structure of soil fungal communities under varying nitrogen fertilizer conditions, using a long-term positioning test on the brown earth of Northeast China. It examined the impact of 31 years of applying of no fertilizer (CK, 0 kg N hm⁻² a⁻¹), the single application of inorganic fertilizer (N₂, urea 135 kg N hm⁻² a⁻¹; N₄, urea 270 kg N hm⁻²·a⁻¹), the single application of organic fertilizer (M₄, pig housing fertilizer 270 kg N hm⁻² a⁻¹), and mixed nitrogen fertilizer (M₂N₂, urea 135 N hm⁻² a⁻¹ + pig housing fertilizer 135 kg N hm⁻² a⁻¹) on the fertility index and fungal community structure of brown earth. The findings indicated the following: Long-term non-fertilization and the single application of chemical nitrogen fertilizer reduced the soil pH value and increased the soil bulk density. The application of organic fertilizer reduced soil bulk density and slowed down the reduction of soil fungal richness caused by nitrogen fertilizer application. The long-term application of different nitrogen fertilizers did not alter the dominant fungal phylum, showing that the dominant phylum in all treatments was Ascomycota. The pH, organic matter, total phosphorus, available phosphorus, total nitrogen, alkaline nitrogen, and available potassium were the main soil factors affecting the structural diversity of soil fungal communities. Total phosphorus explained the greatest differences in soil fungal communities. Full article

(This article belongs to the Special Issue Advances in Fertilizer Technologies and Use to Improve Nutrient Efficiency and Minimize Environmental Impacts)

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14 pages, 1995 KiB

Open AccessArticle

Landscape–Geochemical Assessment of Content of Potentially Toxic Trace Elements in Arctic Soils

by Evgeny Lodygin, Ivan Alekseev and Boris Nesterov

Soil Syst. 2024, 8(4), 120; https://doi.org/10.3390/soilsystems8040120 - 18 Nov 2024

Viewed by 388

Abstract

The importance of research to assess the impact of potentially toxic trace elements (PTEs) on the environment and the importance of environmental monitoring, taking into account the natural variability of soil properties, shaped the aim of our study: to determine the background concentrations [...] Read more.

The importance of research to assess the impact of potentially toxic trace elements (PTEs) on the environment and the importance of environmental monitoring, taking into account the natural variability of soil properties, shaped the aim of our study: to determine the background concentrations of PTEs in different soil profiles in the European Northeast, specifically in the Republic of Komi in Russia, taking into account the landscape and geochemical characteristics of the area. We analysed 173 soil samples from five main soil subtypes. The acid soluble forms of PTEs (Cu, Pb, Zn, Ni, Cd and Mn) were measured using an atomic emission spectrometer. We developed a database of PTE contents and created distribution maps for the Komi Republic using GIS technologies. The study found that PTE levels in soils from accumulative landscapes (such as depressions and floodplains) were generally higher than those in soils from eluvial landscapes (interfluves). We identified correlations between the levels of different PTEs and certain soil properties, providing insights into the biogeochemical migration patterns of these elements. The differentiation of PTEs in soil profiles was more pronounced in loamy automorphic soils and less so in sandy semi-hydromorphic and hydromorphic soils. Most soils, except floodplain soils, showed a clear eluvial–illuvial pattern of PTE distribution within the mineral soil profile, whereas floodplain soils showed a more uniform PTE distribution. The results of this study are useful for assessing the contamination levels of these soil types in high-latitude regions. Full article

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15 pages, 1906 KiB

Open AccessArticle

Bacterial Communities Nodulating Lupinus cosentinii Gus. and Their Inputs in the Worldwide Phylogeography of Lupine Endosymbionts

by Mokhtar Rejili, Mohamed Ali Benabderrahim and Mohamed Mars

Soil Syst. 2024, 8(4), 119; https://doi.org/10.3390/soilsystems8040119 - 17 Nov 2024

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Abstract

Genetic variability in bacterial populations that nodulate Lupinus cosentinii in Tunisia was investigated. Phylogenetic studies of 40 isolates using recA partial sequences categorized them into three clusters within the Bradyrhizobium genus. Twenty-three strains selected from the three clusters were thoroughly examined through housekeeping [...] Read more.

Genetic variability in bacterial populations that nodulate Lupinus cosentinii in Tunisia was investigated. Phylogenetic studies of 40 isolates using recA partial sequences categorized them into three clusters within the Bradyrhizobium genus. Twenty-three strains selected from the three clusters were thoroughly examined through housekeeping genes (recA, glnII and rpoB) multilocus sequence analysis (MLSA). Our results showed that 23 representative strains were distributed in five distinct clusters, with 13 strains belonging to Bradyrhizobium canariense BTA-1^T/Bradyrhizobium lupini USDA3051^T (10 strains) and Bradyrhizobium hipponense aSej3^T (three strains) lineages. Interestingly, eight strains occupied a separate position and could belong to two putative novel Bradyrhizobium species. The nodC phylogeny placed the 23 strains within three symbiovars: genistearum (19 strains), lupini (two strains) and, for the first time, the symbiovar cyanophyllae (two strains). Based on the worldwide phylogeography of rhizobial symbionts nodulating lupine (14 species), our results reported that eight species occurred in more than one continent, and six species were specific for one continent, e.g., Bradyrhizobium rifense, Bradyrhizobium diazoefficiens, Phyllobacterium sp. and Devosia sp. were specific to the African continent, the Bradyrhizobium iriomotense/Bradyrhizobium stylosanthis group to America, and Bradyrhizobium valentinum to the European continent. Full article

(This article belongs to the Special Issue Microbial Community Structure and Function in Soils)

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14 pages, 4518 KiB

Open AccessArticle

Influence of Soil Texture on Carbon Stocks in Deciduous and Coniferous Forest Biomass in the Forest-Steppe Zone of Oka–Don Plain

by Sergey Sheshnitsan, Gennadiy Odnoralov, Elena Tikhonova, Nadezhda Gorbunova, Tatiana Sheshnitsan, Otilia Cristina Murariu and Gianluca Caruso

Soil Syst. 2024, 8(4), 118; https://doi.org/10.3390/soilsystems8040118 - 17 Nov 2024

Viewed by 469

Abstract

Forests play a crucial role in climate change mitigation by acting as a carbon sink. Understanding the influence of soil properties on carbon stocks in forests is essential for developing effective forest management strategies. The aim of the study was to assess the [...] Read more.

Forests play a crucial role in climate change mitigation by acting as a carbon sink. Understanding the influence of soil properties on carbon stocks in forests is essential for developing effective forest management strategies. The aim of the study was to assess the impact of soil texture on carbon stocks in the biomass of deciduous and coniferous tree stands of a forest-steppe ecotone. Soil samples were collected from 55 soil pits, and forest inventory data were obtained from eight permanent sample plots. The results showed that the distribution of mechanical particles in soils, particularly the stocks of silt and clay, significantly influenced the accumulation of carbon in tree stands. The stock of silt and clay was shown to increase with an increase in the diversity of tree species in forests and carbon stocks in forest stands. While soil organic carbon stocks did not exhibit a clear relationship with tree stand carbon stocks, a strong positive correlation (r = 0.802, p < 0.05) was found between the stocks of fine particles in the 2 m root-inhabited soil layer and the carbon stocks in tree biomass. The study provides a classification of forest types based on soil texture, which can facilitate differentiated forest management strategies for enhancing the carbon sequestration potential of forest ecosystems in the forest-steppe zone. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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16 pages, 2702 KiB

Open AccessArticle

Immobilization of Heavy Metals in Biochar Derived from Biosolids: Effect of Temperature and Carrier Gas

by Shefali Aktar, Md Afzal Hossain, Kalpit Shah, Ana Mendez, Cícero Célio de Figueiredo, Gabriel Gasco and Jorge Paz-Ferreiro

Soil Syst. 2024, 8(4), 117; https://doi.org/10.3390/soilsystems8040117 - 15 Nov 2024

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Abstract

Slow pyrolysis was carried out in biosolids under three different temperatures (400, 500 and 600 °C) and two different carrier gases (CO₂ and N₂) on a fluidized bed reactor. The total concentration, chemical fractionation, and plant availability of the heavy [...] Read more.

Slow pyrolysis was carried out in biosolids under three different temperatures (400, 500 and 600 °C) and two different carrier gases (CO₂ and N₂) on a fluidized bed reactor. The total concentration, chemical fractionation, and plant availability of the heavy metals in biochar were assessed by standard methods. The total concentration of Fe, Zn, Cu, Mn, Cr, Ni and Pb increased with the conversion of biosolids to biochar and with increasing pyrolysis temperature. The community’s Bureau of Reference (BCR) sequential extraction identified the migration of metals from toxic and bioavailable to potentially stable available or non-available forms at higher pyrolysis temperatures. Diethylenetriamine penta-acetic acid (DTPA)-extractable metals (Cu, Zn, Cd, Cu, Fe and Pb) were significantly lower in biochar compared to biosolids. By replacing N₂ with CO₂, the total metal concentration of heavy metals was significantly different for Mn, Ni, Cd, Pb and As. There were larger amounts of metals in the residual and oxidizable fractions compared to when N₂ was used as a carrier gas. Consequently, the biochar produced at higher temperatures (500 and 600 °C) in the N₂ environment exhibited lower potential ecological risks than in CO₂ environments (69.94 and 52.16, respectively, compared to values from 75.95 to 151.38 for biochars prepared in N₂). Overall, the results suggest that the higher temperature biochar can support obtaining environmentally safe biochar and can be effective in attenuating the ecological risks of biosolids. Full article

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15 pages, 2868 KiB

Open AccessArticle

Adsorption of Arsenic and Cadmium on Biodegradable and Non-Biodegradable Microplastics in Soil: Comparison Based on Batch Experiment

by Zaw Min Han, Sartaj Ahmad Bhat, Shiamita Kusuma Dewi, Yongfen Wei and Fusheng Li

Soil Syst. 2024, 8(4), 116; https://doi.org/10.3390/soilsystems8040116 - 12 Nov 2024

Viewed by 748

Abstract

In the present study, the adsorption of arsenic(V) and cadmium(II) onto microplastics from poly(butylene succinate-co-butylene adipate) (PBSA) and low-density polyethylene (LDPE) plastic mulch films was investigated through batch experiment. The surface morphology and elemental composition of soil and microplastics were analyzed with scanning [...] Read more.

In the present study, the adsorption of arsenic(V) and cadmium(II) onto microplastics from poly(butylene succinate-co-butylene adipate) (PBSA) and low-density polyethylene (LDPE) plastic mulch films was investigated through batch experiment. The surface morphology and elemental composition of soil and microplastics were analyzed with scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX) and Fourier-transform infrared (FTIR) spectroscopy. The results show that the adsorption of As(V) and Cd(II) on microplastics led to surfaces with coarseness and more cracks, and many small particles. Under the conditions added with 100 pieces of microplastic, PBSA enhanced the adsorption capacity of As(V) (from 0.43 to 0.49 mg/g), and LDPE increased the adsorption of Cd(II) (from 0.174 to 0.176 mg/g) due to the “superimposed effect” caused by hydrogen bonds. Conversely, LDPE reduced the adsorption of As(V) (from 0.44 to 0.40 mg/g) due to a “dilution effect” of PE. Particularly, PBSA exhibited an insignificant effect on the adsorption of Cd(II) in soil during the present study. Overall, our findings provide new insights into the impacts of microplastics on the fate and behavior of heavy metals in the soil system. Full article

(This article belongs to the Special Issue Research on Heavy Metals in Soils and Sediments)

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17 pages, 2653 KiB

Open AccessArticle

Soil Dynamics in Carbon, Nitrogen, and Enzyme Activity Under Maize–Green Manure Cropping Sequences

by Cassio Hamilton Abreu-Junior, Wanderley José de Melo, Roberto Alves de Oliveira, Paulo Henrique Silveira Cardoso, Raíssa de Araujo Dantas, Rodrigo Nogueira de Sousa, Dalila Lopes da Silva, Thiago Assis Rodrigues Nogueira, Arun Dilipkumar Jani, Gian Franco Capra and Gabriel Maurício Peruca de Melo

Soil Syst. 2024, 8(4), 115; https://doi.org/10.3390/soilsystems8040115 - 12 Nov 2024

Viewed by 822

Abstract

The diversification of cropping sequences has a positive impact on soil organic carbon, while improving nutrient cycling and crop yields. The objective of this research was to assess amylase, cellulase, C and N dynamics, and maize yield on a low fertility oxisol in [...] Read more.

The diversification of cropping sequences has a positive impact on soil organic carbon, while improving nutrient cycling and crop yields. The objective of this research was to assess amylase, cellulase, C and N dynamics, and maize yield on a low fertility oxisol in the Brazilian Cerrado. The experiment was conducted under field conditions during three maize crop succession cycles. The treatments consisted of cultivating maize during the summer, after sorghum and lablab cropped as green manure and fallow during the winter. Higher maize yields were achieved by sorghum–maize succession compared to monocropping, due to higher N fertilizer and biomass inputs to topsoil. Sorghum–maize succession also provided a higher proportion of stable C and N compared to other successions. Maize yields declined as tropical soil fertility intrinsically decreased along three crops succession cycles. Cellulase activity decreased over time, whereas amylase activity increased as the plant residues were already in advanced stages of decomposition. The sorghum–maize crop succession stood out compared to lablab and fallow as it provided the highest maize yields, while maintaining higher C and N levels, and amylase activity. This better performance was likely due to larger amounts of incorporated biomass and better mineral N fertilizer management. Full article

(This article belongs to the Topic Carbon and Nitrogen Cycling in Agro-Ecosystems and Other Anthropogenically Maintained Ecosystems)

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30 pages, 3426 KiB

Open AccessArticle

Evaluation of Industrial Hemp Cultivar and Biochar Rate to Remediate Heavy-Metal-Contaminated Soil from the Tar Creek Superfund Site, USA

by Dietrich V. Thurston, Kristofor R. Brye, David M. Miller, Philip A. Moore, Jr., Donald M. Johnson and Mike Richardson

Soil Syst. 2024, 8(4), 114; https://doi.org/10.3390/soilsystems8040114 - 8 Nov 2024

Viewed by 560

Abstract

Soil contamination by cadmium (Cd), lead (Pb), and zinc (Zn) at the Tar Creek superfund site in northeast Oklahoma, United States, remains a threat to the environment and local ecosystem. Phytoremediation with industrial hemp (Cannabis sativa L.) and the use of biochar [...] Read more.

Soil contamination by cadmium (Cd), lead (Pb), and zinc (Zn) at the Tar Creek superfund site in northeast Oklahoma, United States, remains a threat to the environment and local ecosystem. Phytoremediation with industrial hemp (Cannabis sativa L.) and the use of biochar (BC) have been independently shown to be effective methods to remediate heavy-metal-contaminated soils. The objective of this greenhouse study was to evaluate the effects of industrial hemp cultivar (‘Carmagnola’ and ‘Jinma’), biochar rate (0, 2, 5, and 10% by volume), soil contamination level (low, medium, and high), and their interactions on above- (AG) and belowground dry matter (DM) and AG tissue concentrations, as well as uptakes of Cd, Pb, and Zn after 90 days of growth in naturally contaminated soils from the Tar Creek superfund site. Aboveground DM was the largest (p < 0.01) in the low- (0.06 g cm⁻²) and smallest in the high-contaminated soil (0.03 g cm⁻²), and was unaffected (p > 0.05) by cultivar or BC rate. Averaged across BC rates, AG tissue Pb and Zn concentrations from the high-’Carmagnola’ and -’Jinma’ combinations were at least 2.4 times greater than from the other four soil–cultivar combinations. Averaged across cultivars, AG tissue Pb uptake in the high-5 and high-10% BC combinations were at least 2.7 times greater than in the high-0 and high-5% BC combinations, which did not differ. The results indicated that both ‘Carmagnola’ and ‘Jinma’ may be suitable choices for phytoremediation of mixed Cd-, Pb-, and Zn-contaminated soil when grown in combination with 5 or 10% (v/v) BC. Full article

(This article belongs to the Special Issue Soil Bioremediation)

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28 pages, 10086 KiB

Open AccessArticle

Spatial Variability in the Speciation of Lead (Pb) and Other Metals Across Urban Lawns Is Linked to Post-Deposition Weathering Reactions

by Chukwudi E. Nwoko, David M. Singer, Allyson C. Tessin, Rachel Izworski and Chloe Heestand

Soil Syst. 2024, 8(4), 113; https://doi.org/10.3390/soilsystems8040113 - 6 Nov 2024

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Abstract

The historical use of lead (Pb) poses ongoing health risks via exposure to contaminated urban soils. However, there is limited information about heterogeneity in Pb speciation and distribution at the house lot scale. This study determined highly spatially resolved Pb and other metal [...] Read more.

The historical use of lead (Pb) poses ongoing health risks via exposure to contaminated urban soils. However, there is limited information about heterogeneity in Pb speciation and distribution at the house lot scale. This study determined highly spatially resolved Pb and other metal speciation along horizontal transects and vertical soil cores from three homes in the Akron, Ohio (USA) municipal. Solid phase characterization was coupled with a sequential extraction protocol to determine operationally defined speciation (exchangeable (M_EX), reducible (M_RED), oxidizable (M_OX), and residual (M_RES)). Lead and Zn were strongly correlated across all fractions (R² = 0.92). Total extractable Pb and Zn were found in low weight percent concentrations nearest to the homes, and speciation was dominated by M_EX and M_RED. High Pb in the M_EX fraction was correlated with the presence of Pb-bearing paint chips in the soil. Lead in the M_EX fraction in soils near the homes decreased with increasing time due to exterior renovations coupled with increases in Pb and Zn in the M_RED fraction. These results suggest that homes are the dominant source of Pb and Zn due to the weathering of exterior surfaces and highlight the acute risk of exposure to more labile Pb immediately following exterior renovations and damage to home exteriors in areas of older housing stock. Full article

(This article belongs to the Special Issue Research on Heavy Metals in Soils and Sediments)

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15 pages, 1210 KiB

Open AccessArticle

Cultivable Rhizosphere Microbial Community Structure in the Yaqui Valley’s Agroecosystems

by Valeria Valenzuela Ruiz, Edgar Cubedo-Ruiz, Maria Maldonado Vega, Jaime Garatuza Payan, Enrico Yépez González, Fannie Isela Parra Cota and Sergio de los Santos Villalobos

Soil Syst. 2024, 8(4), 112; https://doi.org/10.3390/soilsystems8040112 - 31 Oct 2024

Viewed by 546

Abstract

Agricultural practices affect the physical, chemical, and biological properties of soil in agroecosystems. This study evaluated the impact of food production strategies on the rhizosphere microbial communities in the Yaqui Valley, Mexico, on key crops (Medicago sativa, Brassica oleracea, Asparagus [...] Read more.

Agricultural practices affect the physical, chemical, and biological properties of soil in agroecosystems. This study evaluated the impact of food production strategies on the rhizosphere microbial communities in the Yaqui Valley, Mexico, on key crops (Medicago sativa, Brassica oleracea, Asparagus officinalis, Phaseolus vulgaris, Citrus sinensis, Zea mays, Solanum tuberosum, Triticum durum, and an undisturbed native ecosystem). Soil samples were collected from 30 cm depths across one-hectare fields and analyzed for bulk density, pH, organic matter content, and electrical conductivity. Standardized methods were used for these analyses, along with microbial isolation through culturing, PCR amplification, and DNA sequencing for microbial identification. The use of synthetic fertilizers in the region was linked to increased salinity and soil compaction. Organic matter content was notably low at ≤1.4%, which negatively impacted microbial diversity. A total of 317 microbial strains were isolated, with bacteria comprising 73% and fungi 27%. Bacillus was the most dominant bacterial genus (41% of isolates), while Aspergillus was the most abundant fungal genus (31% of isolates). Crop-specific microbial strains were identified. This study provides the first detailed insight into how agricultural practices shape microbial communities in the Yaqui Valley’s major crops, highlighting the link between soil properties and microbial diversity. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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17 pages, 7106 KiB

Open AccessArticle

Lowland Integrated Crop–Livestock Systems with Grass Crops Increases Pore Connectivity and Permeability, Without Requiring Soil Tillage

by Jordano Vaz Ambus, Amanda Romeiro Alves, Douglas Leandro Scheid, Antonio Celso Dantas Antonino and José Miguel Reichert

Soil Syst. 2024, 8(4), 111; https://doi.org/10.3390/soilsystems8040111 - 30 Oct 2024

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Abstract

Enhancing integrated crop–livestock systems (ICLSs) to improve land-use efficiency is a critical goal. Understanding the ICLS impacts on lowland soils is key to sustainable agricultural practices. Our objective was to test whether adopting ICLSs in lowlands improves soil structure, pore connectivity, and water [...] Read more.

Enhancing integrated crop–livestock systems (ICLSs) to improve land-use efficiency is a critical goal. Understanding the ICLS impacts on lowland soils is key to sustainable agricultural practices. Our objective was to test whether adopting ICLSs in lowlands improves soil structure, pore connectivity, and water and air permeability. This study was conducted in a long-term field trial, consisting of the following production systems with flood-irrigation rice: rice–fallow–rice, under conventional tillage and absence of grazing (RFR-ct); rice-grazed ryegrass–rice, under no-tillage and grazing (RGrR-nt); rice-grazed ryegrass–soybean-grazed ryegrass–rice, under no-tillage and grazing (RGrS/RGrR-nt); and a grazed pasture-consortium (winter) and succession field (summer), with no-till rice every 4 years (P4R-nt). Core samples were collected after grazing (October 2018), harvesting (March 2019), and grazing (October 2019). We analyzed soil air permeability, saturated hydraulic conductivity, pore connectivity by computed tomography. Soil tillage in a semi-direct system generated discontinuous porosity. Systems with intense trampling or less surface protection are affected by shearing on topsoil, reducing pore continuity. ICLSs are mainly composed of ryegrass–rice mitigated the harmful effects of trampling, and improved soil structure and functioning. Systems without soil tillage exhibited higher pore connectivity and pores with vertical orientation. Finally, soil tillage is not required to improve structural quality in ICLSs. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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27 pages, 6370 KiB

Open AccessArticle

Soil Physical Properties, Root Distribution, and “Ponkan” Tangerine Yield Across Different Rootstocks in a Deep Tillage Ultisol

by Pedro Antônio Namorato Benevenute, Laura Beatriz Batista Melo, Samara Martins Barbosa, Mariany Isabela Soares Domingues, Isabela Cristina Filardi Vasques, Everton Geraldo de Morais, Lucas Roberto de Castro, Geraldo César de Oliveira, Ester Alice Ferreira and Bruno Montoani Silva

Soil Syst. 2024, 8(4), 110; https://doi.org/10.3390/soilsystems8040110 - 25 Oct 2024

Viewed by 1479

Abstract

Deep soil tillage and proper rootstock selection mitigate the root development limitations in Ultisol’s Bt horizon, enhancing the citrus yield potential. This study evaluates the root spatial distribution of three Ponkan tangerine rootstocks in Ultisol under deep tillage alongside the physical-hydric attributes and [...] Read more.

Deep soil tillage and proper rootstock selection mitigate the root development limitations in Ultisol’s Bt horizon, enhancing the citrus yield potential. This study evaluates the root spatial distribution of three Ponkan tangerine rootstocks in Ultisol under deep tillage alongside the physical-hydric attributes and plant measurements. The experimental area underwent furrow creation, subsoiling, and hole opening for planting. The treatments included three rootstocks: “Cravo Santa Cruz” (CSC), “Sunki Tropical” (ST), and “Citrandarin Índio” (CI). Under the Ultisol preparation, these rootstocks were compared to a native forest area (FA). Three years post-initial tillage, soil samples were collected at depths of 0–0.05, 0.35–0.40, and 0.45–0.50 m from the pre-established positions. The evaluation encompassed soil dispersive clay, available water, crop water use, plant measurement, and crop yield. The root evaluation utilized the crop profile method and 2D images, with subsequent surface mapping of the root variables, number (NR), and diameter (RD) analyzed via kriging geostatistical analysis. The Ultisol showed significant changes in its physical-hydric attributes regarding structural change and more excellent clay dispersion, with a considerable contribution to the micropore volume. Deep tillage effectively improved the root spatial distribution, especially concerning the number and diameter of roots, and enhanced the water use, reflected in the vegetative growth and yield, with the rootstock CSC standing out. Full article

(This article belongs to the Special Issue Land Use and Management on Soil Properties and Processes)

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19 pages, 3213 KiB

Open AccessArticle

Processing Municipal Waste for Phytostabilization of Heavy Metal Contaminated Soils

by Shohnazar Hazratqulov, Georgina von Ahlefeldt, Rui Liu, Holger Bessler, Hernán Almuina-Villar, Alba Dieguez-Alonso and Christof Engels

Soil Syst. 2024, 8(4), 109; https://doi.org/10.3390/soilsystems8040109 - 24 Oct 2024

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Abstract

Background: Organic amendments are often used for the phytostabilization of heavy metal-contaminated soils. This study investigated the suitability of different municipal waste processing methods for phytostabilization. Methods: The two feedstocks, biowaste, and green waste, were tested without pretreatment after composting or after pyrolysis [...] Read more.

Background: Organic amendments are often used for the phytostabilization of heavy metal-contaminated soils. This study investigated the suitability of different municipal waste processing methods for phytostabilization. Methods: The two feedstocks, biowaste, and green waste, were tested without pretreatment after composting or after pyrolysis at different temperatures and atmosphere compositions. The suitability of the differently pretreated amendments for phytostabilization was tested on sewage farm soil contaminated with Cd, Cu, Ni, and Zn by measurement of maize growth, mineral content, and mobile heavy metal concentrations in the bulk and rhizosphere soil. Results: In contaminated soils, shoot and root growth increased markedly due to the soil amendments. Shoot concentrations of all four heavy metals were significantly higher in contaminated than non-contaminated soil, whereas Fe concentrations were lower in contaminated soil. The amendments increased shoot Cd concentrations and did not significantly affect the other elements. In contaminated soil, concentrations of heavy metals were generally lower in the rhizosphere than in the bulk soil. The soil amendments markedly lowered soil heavy metal concentrations, whereby the decrease was significantly influenced by feedstock and pretreatment. The differences in the amendments’ ability to reduce the soil mobile heavy metals were primarily, but not exclusively, determined by their effect on soil pH. Conclusion: The feedstock processing conditions significantly influenced the phytostabilization performance of green waste and biowaste. Optimal processing for phytostabilization depends on the heavy metal most important in the contamination of a specific site. Full article

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21 pages, 3976 KiB

Open AccessArticle

No-Till and Crop Rotation Are Promising Practices to Enhance Soil Health in Cotton-Producing Semiarid Regions: Insights from Citizen Science

by Tirhas A. Hailu, Pawan Devkota, Taiwo O. Osoko, Rakesh K. Singh, John C. Zak and Natasja van Gestel

Soil Syst. 2024, 8(4), 108; https://doi.org/10.3390/soilsystems8040108 - 21 Oct 2024

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Abstract

This on-farm study was conducted to assess the impact of six prevalent crop management practices adopted by growers in West Texas on various indicators of soil health. This study is a part of a citizen science project, where we collaborated with cotton growers [...] Read more.

This on-farm study was conducted to assess the impact of six prevalent crop management practices adopted by growers in West Texas on various indicators of soil health. This study is a part of a citizen science project, where we collaborated with cotton growers who helped with standardized sample and data collection from 2017 to 2022. This project aimed to identify soil management practices that increase carbon sequestration, enhance biological activities, and improve overall soil health. We monitored soil moisture, soil organic matter (SOM), inorganic nitrogen (NH₄⁺-N and NO₃⁻-N) and other exchangeable nutrients, and soil microbial abundances as obtained via fatty acid methyl ester (FAME) in 85 fields, incorporating different management practices during the cotton growing season. In our study, volumetric moisture content (VWC) was increased by no-till, irrigation, and crop rotation, but the addition of residue decreased VWC. No-till, irrigation, and crop rotation increased SOM, but a cover crop decreased SOM. No-till and residue retention also increased microbial biomass carbon (MBC). Tillage, irrigation, and crop rotation influenced the abundance of the main microbial groups, including bacterial, fungi, and arbuscular mycorrhizal fungi (AMF). Additionally, water content, SOM, and microbial abundances are correlated with clay percentage. Our results indicate that no-till and crop rotation are the two most crucial soil management approaches for sustainable soil health. As such, implementing both no-till and crop rotation in the cropping systems has the most promising potential to increase the soil resilience in dryland cotton production in semiarid regions, thereby helping growers to maintain cotton production. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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23 pages, 4101 KiB

Open AccessArticle

Use of Edaphic Bioindicators to Mitigate Environmental Impact and Improve Agricultural Research and Training

by Ana Cano-Ortiz, José Carlos Piñar Fuentes, Juan Peña-Martínez and Eusebio Cano

Soil Syst. 2024, 8(4), 107; https://doi.org/10.3390/soilsystems8040107 - 18 Oct 2024

Viewed by 1165

Abstract

The world is currently experiencing unsustainable development, which poses significant risks to global society. In response, there is a growing advocacy for sustainable development across all sectors, driven by social resilience. This shift is fostering substantial socio-environmental tensions. However, the combined power of [...] Read more.

The world is currently experiencing unsustainable development, which poses significant risks to global society. In response, there is a growing advocacy for sustainable development across all sectors, driven by social resilience. This shift is fostering substantial socio-environmental tensions. However, the combined power of scientific research and social education has the potential to reverse this trend. Transitioning from an unsustainable territorial model to a sustainable one is both feasible and economically profitable. This transition can be achieved through knowledge of soil bioindicators, which provide valuable information about soil nutrient content. By understanding these indicators, nutrient inputs can be tailored, reducing or eliminating pollutants such as excessive fertilizers, herbicides, and pesticides. Training experts and raising social awareness through education on new research are essential steps in this process. For decades, it has been recognized that globalization, industrialization, and population growth have driven unsustainable development, leading to degraded agroecosystems. To address this issue, government institutions are promoting sustainability through ecological agriculture and CO₂ reduction, both of which can be supported by the use of soil bioindicators. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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9 pages, 1802 KiB

Open AccessCommunication

The Past Is Never Dead: Soil Pollution from Mining in the Copiapó River Basin (Northern Chile)

by Luna Araceli Pérez, Tatiana Izquierdo, Manuel Abad, Manuel Caraballo, Sebastián Ureta and Francisco Ruiz

Soil Syst. 2024, 8(4), 106; https://doi.org/10.3390/soilsystems8040106 - 11 Oct 2024

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Abstract

This short paper analyses the concentrations of two major components (Fe, S) and eight trace elements (As, Au, Co, Cu, Hg, Ni, Mn, Zn) in soils and tailings from Tierra Amarilla (northern Chile) using ICP-Ms analysis. The levels of As, Au, Cu, Fe [...] Read more.

This short paper analyses the concentrations of two major components (Fe, S) and eight trace elements (As, Au, Co, Cu, Hg, Ni, Mn, Zn) in soils and tailings from Tierra Amarilla (northern Chile) using ICP-Ms analysis. The levels of As, Au, Cu, Fe and S are very high and come from polymetallic sulphides from nearby mines, together with minor contributions of Co, Ni and Mn. Hg has its origin in the extreme seasonal flows of the Copiapó River, which erodes the dumps of old precious metal mines. These high concentrations require further analysis of possible metal immobilisation techniques, bioavailability or analysis in cultivated plants. Full article

(This article belongs to the Special Issue Research on Heavy Metals in Soils and Sediments)

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22 pages, 3699 KiB

Open AccessReview

Lifting the Profile of Deep Forest Soil Carbon

by Loretta G. Garrett, Alexa K. Byers, Kathryn Wigley, Katherine A. Heckman, Jeff A. Hatten and Steve A. Wakelin

Soil Syst. 2024, 8(4), 105; https://doi.org/10.3390/soilsystems8040105 - 7 Oct 2024

Viewed by 1210

Abstract

Forests are the reservoir for a vast amount of terrestrial soil organic carbon (SOC) globally. With increasing soil depth, the age of SOC reportedly increases, implying resistance to change. However, we know little about the processes that underpin deep SOC persistence and what [...] Read more.

Forests are the reservoir for a vast amount of terrestrial soil organic carbon (SOC) globally. With increasing soil depth, the age of SOC reportedly increases, implying resistance to change. However, we know little about the processes that underpin deep SOC persistence and what deep SOC is vulnerable to climate change. This review summarizes the current knowledge of deep forest SOC, the processes regulating its cycling, and the impacts of climate change on the fate of deep forest SOC. Our understanding of the processes that influence deep SOC cycling and the extent of SOC stores is limited by available data. Accordingly, there is a large degree of uncertainty surrounding how much deep SOC there is, our understanding of the influencing factors of deep SOC cycling, and how these may be distinct from upper soil layers. To improve our ability to predict deep SOC change, we need to more accurately quantify the deep SOC pool and deepen our knowledge of how factors related to the tree root–soil–microbiome control deep SOC storage and cycling. Thereby, addressing the uncertainty of deep SOC contribution in the global C exchange with climate change and concomitant impacts on forest ecosystem function and resilience. Full article

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16 pages, 1282 KiB

Open AccessArticle

Omitting the Application of Nitrogen or Potassium Reduced the Growth of Young Chestnut (Castanea sativa) Trees, While a Lack of Boron Decreased Fruit Yield

by Margarida Arrobas, Soraia Raimundo, Carlos Manuel Correia and Manuel Ângelo Rodrigues

Soil Syst. 2024, 8(4), 104; https://doi.org/10.3390/soilsystems8040104 - 30 Sep 2024

Viewed by 700

Abstract

The chestnut tree (Castanea sativa Mill.) is gaining importance in the mountainous regions of southern Europe due to the high value of its fruits. It is essential to establish effective cultivation protocols, considering that this species is still relatively understudied. In this [...] Read more.

The chestnut tree (Castanea sativa Mill.) is gaining importance in the mountainous regions of southern Europe due to the high value of its fruits. It is essential to establish effective cultivation protocols, considering that this species is still relatively understudied. In this study, we present the outcomes of the initial establishment of a chestnut orchard conducted through a nutrient omission trial for four years. The treatments included a fertilization plan with nitrogen, phosphorus, potassium, and boron (NPKB), the control, and four other treatments corresponding to the omission of each nutrient (-NPKB, N-PKB, NP-KB, NPK-B). The -NPKB and NP-KB treatments showed significantly lower trunk circumferences and canopy volumes compared to the other treatments. The NPK-B treatment resulted in the lowest fruit production, with a total accumulated yield (2020–2022) of 0.56 kg tree^–1, a value significantly lower than that of NPKB (1.12 kg tree^–1) and N-PKB (1.19 kg tree^–1). The assessment of nutrient concentrations in the leaves revealed plants with deficient levels of B and K in treatments that did not receive these nutrients. Conversely, N levels in the leaves in the -NPKB treatment fell within the sufficiency range (20 to 28 g kg^–1). This suggests that the sufficiency range should be adjusted to higher values, given the treatment’s effect on tree growth. It was also observed that the -NPKB treatment led to lower soil organic matter compared to the other treatments, likely due to reduced herbaceous vegetation development under the canopy, leading to decreased organic substrate deposition in the soil. The main findings of this study are that N and K were crucial elements for the optimal growth of chestnut trees, while B played a significant role in fruit production. Full article

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17 pages, 4527 KiB

Open AccessArticle

An Integrated Approach to Remediate Saline Soils and Mining Waste Using Technosols and Pasture Development

by Antonio Aguilar-Garrido, Patrícia Vidigal, Ana Delaunay Caperta and Maria Manuela Abreu

Soil Syst. 2024, 8(4), 103; https://doi.org/10.3390/soilsystems8040103 - 27 Sep 2024

Viewed by 752

Abstract

Reclaiming marginal lands such as saline soils or mining waste for livestock grazing through Technosols and phytostabilisation can provide a solution to the growing food demand. This study evaluated the enhancement of soil properties by two Technosol constructions, along with pasture development. The [...] Read more.

Reclaiming marginal lands such as saline soils or mining waste for livestock grazing through Technosols and phytostabilisation can provide a solution to the growing food demand. This study evaluated the enhancement of soil properties by two Technosol constructions, along with pasture development. The experimental set-up consisted of gossan waste (G), Fluvisol (VF), Technosol/gossan (TG), and Technosol/Fluvisol (TVF), both Technosols consisting of G and VF, respectively, mixed with organic and inorganic amendments. These substrates were sown in pasture in pots (1.5 dm³) that was cut one and two months after sowing to simulate grazing. Both Technosols improved soils properties, with the acidity of G neutralising in TG. Yet, in TVF, a 65% reduction in salinity and a 60% drop in exchangeable Na occurred compared with VF. Nutrient pool, aggregate stability, and microbiological activity were also improved. Dehydrogenase activity was practically 0 in G, while in TG it was 15 times higher, and with pasture it increased 6-fold. In FV, some activity was already present, but in TVF it was six times higher and even increased with pasture. Finally, these improvements allowed the establishment of a healthy pasture, with twice the biomass and less accumulation of potentially hazardous elements in TG, and considerable growth in TVF. Thus, the co-application of Technosols and pasture may be effective in converting marginal lands into productive areas (grazing, foraging, biomass energy). Full article

(This article belongs to the Special Issue Crop Response to Soil and Water Salinity)

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18 pages, 3104 KiB

Open AccessFeature PaperArticle

Residue Addition Can Mitigate Soil Health Challenges with Climate Change in Drylands: Insights from a Field Warming Experiment in Semi-Arid Texas

by Pawan Devkota, Rakesh K. Singh, Nicholas G. Smith, Lindsey C. Slaughter and Natasja van Gestel

Soil Syst. 2024, 8(4), 102; https://doi.org/10.3390/soilsystems8040102 - 24 Sep 2024

Viewed by 795

Abstract

Texas cotton production is facing challenges from increased temperatures and extended droughts. We sought to determine whether applying a multi-species grass mulch on the surface of cotton fields in a semiarid region would mitigate some of the negative effects of climate change. We [...] Read more.

Texas cotton production is facing challenges from increased temperatures and extended droughts. We sought to determine whether applying a multi-species grass mulch on the surface of cotton fields in a semiarid region would mitigate some of the negative effects of climate change. We used open-top chambers (OTCs) to mimic climate warming and compared whether the effects of residue addition were similar between dryland and irrigated cotton fields located in the High Plains region of Texas during the summer of 2021. The OTCs raised the average air temperature by 2 °C. Under experimental warming, residue addition increased moisture content in non-irrigated (i.e., dryland) soils (+9.2%) and reduced the daily temperature range (by −1.4 °C) relative to uncovered soils. Furthermore, when pooled across irrigation and warming treatments, the addition of residue increased microbial biomass, soil respiration (+78.2%), and cotton yield (+15.2%) relative to uncovered soils. OTCs further enhanced the residue effects on microbial biomass by 34.9%. We also observed higher soil organic matter, microbial biomass, cotton biomass, and yield in irrigated fields compared to dryland, irrespective of residue addition. Our findings suggest that residue addition in dryland agriculture can mitigate the adverse effects of warming by stabilizing soil microclimates and promoting microbial growth and biomass by providing a more labile source of carbon, which, in turn, could boost the yield of cotton plants. Full article

(This article belongs to the Special Issue Research on Soil Management and Conservation: 2nd Edition)

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Soil Syst., Volume 8, Issue 4 (December 2024) – 21 articles

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