Geoderma Regional最新文献

{"title":"Rodent burrows in chernozems as a paleoarchive of vegetation dynamics: A case study from the central chernozem region of Russia","authors":"Valerii E. Pimenov ,&nbsp;Elena V. Ponomarenko ,&nbsp;Yury G. Chendev ,&nbsp;Ekaterina G. Ershova ,&nbsp;Maria I. Dergacheva ,&nbsp;Maria A. Smirnova","doi":"10.1016/j.geodrs.2025.e00969","DOIUrl":"10.1016/j.geodrs.2025.e00969","url":null,"abstract":"<div><div>Northern сhernozems are formed at the interface of the steppe zone with broadleaved forests. Boundaries between these ecosystems were shifting in the Holocene, following changes in climate and land use practices. It is expected that modern chernozemic soils went through multiple stages of development under various plant formations that altered soil properties, but reconstruction of vegetation dynamics in the steppe region is limited by a scarcity of paleoecological archives, such as peatlands and lakes. Zooturbation is the hallmark of arid regions; it results in the formation of infilled burrows — <em>krotovinas</em>, that are numerous and ubiquitous in chernozems. In northern steppes most krotovinas are created by the greater mole-rat (<em>Spalax microphthalmus</em>). Infill of vertical shafts of krotovinas varies in color and humus content within one soil profile, suggesting that they have been formed over a considerable timespan. We analyzed pollen composition of the vertical krotovinas and compared it to pollen spectra of surficial horizons in chernozems of northern steppes. All krotovinas contained pollen of the quantity and preservation degree that enabled vegetation reconstruction. Surface pollen spectra reflected disturbed meadow-steppe vegetation, whereas pollen spectra of krotovinas varied from those of forested to dry steppe communities. Ordination of pollen spectra from krotovinas according to their humus content suggests major successions in vegetation cover from <em>Artemisia</em>-dominated xerophytic ecosystems to wet, warm-climate meadow-steppes affected by fires and pastoralism, and further to more forested landscapes. The results show that infilled vertical burrow shafts of steppe rodents can be used as a paleoecological archive similar to paleosols.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00969"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Examining farmers' perceptions of soil fertility and its use in field practices in Northern Ghana","authors":"Yoshie Yageta ,&nbsp;Joseph Agebase Awuni ,&nbsp;Vincent Kodjo Avornyo ,&nbsp;Junji Koide ,&nbsp;Satoru Muranaka ,&nbsp;Satoshi Nakamura","doi":"10.1016/j.geodrs.2025.e00972","DOIUrl":"10.1016/j.geodrs.2025.e00972","url":null,"abstract":"<div><div>Expanding sustainable soil fertility management is essential for sustainable agricultural production in Sub-Saharan Africa. This case study was conducted to understand local perceptions of soil fertility and strategies farmers use for field management in Northern Ghana. The study objectives were to 1) identify the indicators of farmers' perceptions of soil fertility and 2) assess the impacts of local knowledge of soil fertility on field management, particularly crop selection, in Northern Ghana. Soil sampling for physicochemical analysis and interviews with farmers regarding their perceptions of soil fertility, cultivated crops, and organic amendments were conducted in 300 farm fields in 60 communities. Soils perceived as fertile by farmers had significantly higher values of pH (H₂O), pH (KCl), electrical conductivity, total nitrogen, total carbon, Ca, K, Mg, and cation exchange capacity, followed by normal, less fertile, and infertile soils. A comparison of the crops cultivated in 2019 and 2020 at each farm revealed that cash crops (groundnuts, soybeans, and yams) were not cultivated in soils perceived as infertile by farmers. The use of organic amendments was relatively low; however, they were often applied to fields perceived as infertile to improve fertility. Our findings can be useful for recommending suitable crop allocation for specific local conditions.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00972"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human-induced transformation of chernozems in the Central Russian Upland: a role of benchmark and nearly-benchmark soils in assessing","authors":"Yu.G. Chendev ,&nbsp;M.A. Smirnova ,&nbsp;A.N. Gennadiev","doi":"10.1016/j.geodrs.2025.e00971","DOIUrl":"10.1016/j.geodrs.2025.e00971","url":null,"abstract":"<div><div>Evaluating the human-induced transformation of chernozems — the most fertile soils in the world — requires the presence of undisturbed benchmark soils for comparison. Traditionally, such benchmarks are found within protected areas. However, given the near-total agricultural development of the chernozem zone, including the Central Russian Upland, protected areas with chernozems are scarce and cover limited extents. In this context, near-benchmark chernozems — those that have never been ploughed but are located in hayfields and pastures — can serve as valuable references. These soils, though subject to minimal agricultural use (e.g., mowing and grazing), retain properties closely resembling those of benchmark chernozems.</div><div>This study presents a comparative analysis of the morphological, physical, and chemical properties of: a) chernozems in protected areas (benchmark chernozems); b) never-ploughed chernozems in hayfields and pastures (near-benchmark chernozems); and c) ploughed chernozems. The findings reveal the extent and direction of human-induced transformation in chernozem soils. Ploughing leads to soil compaction at depths of 20–30 cm, reduced organic carbon stocks (especially in the upper 50 cm), and upward movement of soil carbonates. In hayfields and pastures, grazing and periodic mowing cause compaction to a depth of 50 cm and similar upward migration of soil carbonates.</div><div>Soils under hayfields and pastures show no significant differences from protected chernozems in terms of organic carbon stocks (0–20 cm, 0–50 cm, 1 m, and 2 m layers) and morphological properties. Thus, chernozems under hayfields and pastures, despite minor anthropogenic impacts, retain many properties similar to those of protected soils. They are valuable for reconstructing the natural characteristics of pre-industrial chernozems and can serve as benchmarks for assessing the transformation of arable chernozems.</div><div>These findings underscore the need to preserve and expand protected areas with never-ploughed chernozems and highlight the importance of developing sustainable land-use strategies to prevent soil degradation.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00971"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of phosphorus pools, sorption capacity and supply potential of agricultural soils of Tigray, Northern Ethiopia","authors":"Gidena T. Reda ,&nbsp;Mirjam S. Breure ,&nbsp;David P. Wall ,&nbsp;Abbadi G. Reda ,&nbsp;Rachel E. Creamer","doi":"10.1016/j.geodrs.2025.e00970","DOIUrl":"10.1016/j.geodrs.2025.e00970","url":null,"abstract":"<div><div>Phosphorus (P) is a major limiting nutrient for food production in Ethiopian agricultural soils, primarily due to low P fertilizer application and strong P fixation caused by inherent soil properties. Understanding the supply potential and distribution of soil P pools is essential for optimising P fertilizer recommendations, particularly in Northern Ethiopian soils, where strong P fixation occurs due to highly weathered soil minerals, and associated soil properties, which affect P availability. The objectives of this study were to: (i) investigate the distribution of P across different soil P pools and (ii) examine the P sorption capacity and supply potential of agricultural soils in relation to P availability as controlled by Ca/P and Al/P ratios. Soil samples were collected from forty-three locations across three districts in northern Ethiopia: Endamekhoni (ED), Laelay-Maichew (LM) and Atsbi-Wenberta (AW). Availability and distribution of P across different soil P pools were assessed using Mehlich3 (M3) extraction and Hedley sequential extraction scheme, respectively. Soil total P was highly variable across sites, ranging between 348 and 3108 mg kg⁻¹. The availability of P was plotted against ratios of Ca and Al over P to identify change points, indicative of P supply potential to crops. Results showed that the change points for P supply potential were different across the three districts, likely reflecting differences in soil parent materials. The Ca/P ratio change points that determine the availability of P in soils were 696:1, 1926:1 and 401:1, for the districts of ED, LM and AW, respectively. Similarly, the change points of Al/P ratio for the ED, LM and AW were 97:1, 284:1, and 30:1, respectively. The accessibility of P for plant uptake increased when the ratios of Ca/P and Al/P were below the change points and vice versa. In conclusion P fertilizer recommendations should consider the change points of Ca/P and Al/P ratios, as these ratios control the bioavailability of soil P and elucidate the P sorption capacity and supply potential of the Ethiopian agricultural soils.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00970"},"PeriodicalIF":3.1,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144212335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the effect of land use and manure management on soil carbon sequestration in tropical mixed crop-livestock systems: A case study in Guadeloupe (Caribbean)","authors":"Jorge Sierra ,&nbsp;Fabien Stark ,&nbsp;Audrey Fanchone","doi":"10.1016/j.geodrs.2025.e00968","DOIUrl":"10.1016/j.geodrs.2025.e00968","url":null,"abstract":"<div><div>In tropical regions, mixed crop-livestock systems (MCLS) afford opportunities to achieve sustainable agriculture by supplying several ecosystem services, including soil C sequestration. The aim of this study was to assess soil C sequestration in representative tropical (Caribbean) MCLS in the Guadeloupe Archipelago. We designed a modeling approach at the scale of the farm and cropping system, based on a data-driven model of soil organic C (SOC) balance coupled to three databases. The variables included soil properties, manure properties (fresh and stored-composted), and farm characteristics of the eight MCLS. The results indicated that land use (i.e., relative area occupied by perennial crops) was the main factor controlling soil C sequestration at the farm scale and that pasture and sugarcane systems were crucial for maintaining or increasing SOC stocks. Under the current MCLS management, only 16 % of manure production is used to fertilize croplands. This mode of fertilization was found to be ineffective at the farm scale, given that it resulted in low (average + 0.03 % yr⁻¹) or negative (up to −0.3 % yr⁻¹) soil C sequestration; manure C inputs did not compensate for SOC outputs by mineralization in annual systems. It is estimated that increasing manure use to near 100 % would increase the level of soil C sequestration 3.5-fold (average + 0.11 % yr⁻¹) and could compensate for up to 20 % of the reduction in C inputs from crop residues used as animal feed. These effects were 50 % higher for fresh manure than for stored-composted manure because of mass and C losses during storage, which reduced the level of manure C inputs to the soil. Overall, the results indicate that increasing manure use and shortening the storage period through, for example, more frequent split applications would be suitable to boost soil C sequestration and sustainability in tropical MCLS by decreasing soil C losses and increasing C retention in soil. However, trade-offs must be made between managing the frequency of applications, the cost and degree of manual labor required, and optimizing the overall health of the MCLS.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00968"},"PeriodicalIF":3.1,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144131135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genesis, paleoenvironmental history and landscape interplays of Holocene buried soils in Minas Gerais, Southeastern Brazil","authors":"Athos Alves Vieira ,&nbsp;Rafael Gomes Siqueira ,&nbsp;José João Lelis Leal de Souza ,&nbsp;Demetrio Angelo Lama Isminio ,&nbsp;Márcio Rocha Francelino ,&nbsp;Carlos Ernesto Gonçalves Reynaud Schaefer ,&nbsp;Elpídio Inácio Fernandes-Filho","doi":"10.1016/j.geodrs.2025.e00967","DOIUrl":"10.1016/j.geodrs.2025.e00967","url":null,"abstract":"<div><div>Buried soils are of great relevance for studies that aim to reconstitute paleoclimates, paleovegetation and paleosurfaces. However, very little is known about the genesis and paleoclimate history of buried soils in the Mantiqueira Range, Southeastern Brazil. Therefore, we investigated a toposequence of buried soils near the Serra do Brigadeiro – Minas Gerais State, aiming to comprehend the environmental conditions under which these soils were formed. To this end, we described, classified and analyzed eight pedocomplexes constituted of buried and overlying soils, focusing on their chemical, physical and mineralogical attributes. We also analyzed the isotopic composition (δ¹³C and δ¹⁵N) of organic matter and dated charcoal fragments using radiocarbon (¹⁴C) dating. We also dated the Ab horizons using Optically Stimulated Luminescence, aiming to obtain the timing of soil burial. Soils were, in general, acidic, clayey to very clayey, nutrient-poor, and with mineralogy dominated by kaolinite, gibbsite and goethite, typical of tropical soils. Past soils, found in the lower slopes, were buried by colluvial deposits derived from mass movements, mainly triggered during the Mid-Holocene (7500 to 5000 yr BP), possibly under dry and seasonal climates. The slope colluvium consists of highly pedogenized material with a degree of weathering similar to that of the buried soils, which justifies the absence of lithological discontinuities. The δ¹³C signal, indicating a mixture of C3 and C4 plants, suggests that the colluvial processes were intensified by the presence of more open vegetation, presumably a wooded savanna. The abundant presence of charcoal suggests the frequent occurrence of paleofires, either climate-induced or anthropogenic.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00967"},"PeriodicalIF":3.1,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144114853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversification, age, and organic amendments affect microbial and enzymatic activities in soils of Arabica coffee plantations in the tropical lowlands of Colombia","authors":"William Andrés Cardona ,&nbsp;Joana Falcao Salles ,&nbsp;Luis Gabriel Bautista Montealegre ,&nbsp;Barbara Prack Mc Cormick ,&nbsp;Carlos Mario González Baena ,&nbsp;Yeinny Carolina Pisco Ortiz ,&nbsp;Eric Scopel ,&nbsp;Martha Marina Bolaños Benavides ,&nbsp;Miguel Andrés Arango Argoti ,&nbsp;Pablo Tittonell","doi":"10.1016/j.geodrs.2025.e00966","DOIUrl":"10.1016/j.geodrs.2025.e00966","url":null,"abstract":"<div><div>Coffee cultivation is essential for tropical agriculture and rural livelihoods in Latin America, Africa, and Asia. However, coffee production in tropical low-altitude regions characterized by acidic soils and elevated temperatures faces significant challenges, and the soil microbiological dynamics under these environments remain poorly understood. This study assessed the impact of agricultural practices and edaphoclimatic variables on soil biological indicators, such as enzymatic activities and basal respiration in coffee fields located below 1000 m altitude in Colombia. Surveys conducted with 40 coffee growers characterized various agronomic practices and socioeconomic factors, and 150 soil samples were collected from their coffee crops of differing ages and associated species. Enzymatic activities were measured using specific substrates, including acid and alkaline phosphatase, arylsulfatase, urease, dehydrogenase, and β-glucosidase. Statistical analyses including constrained ordination, Spearman correlations, and mixed models, were employed to evaluate variations in biological indicators concerning agronomic practices and edaphoclimatic conditions.</div><div>Four groups of coffee growers were identified based on their management practices. Livestock-focused growers who utilized organic fertilizers exhibited the highest enzymatic activity, with measurements of acid phosphatase at 365 μg g⁻¹ h⁻¹, alkaline phosphatase at 49 μg g⁻¹ h⁻¹, and arylsulfatase at 137 μg g⁻¹ h⁻¹. In contrast, traditional growers with older plantations recorded the lowest acid phosphatase (215 μg g⁻¹ h⁻¹), alkaline phosphatase (36 μg g⁻¹ h⁻¹), and β-glucosidase (30 μg g⁻¹ h⁻¹). Basal soil respiration was significantly higher in shade-grown coffee compared to sun-grown (43.0 and 12.6 mg CO₂–C kg⁻¹ soil d⁻¹, respectively). Coffee intercropping with Musaceae, Cocoa, and <em>Inga</em> species, organic fertilization, and liming enhanced soil biological indicators.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00966"},"PeriodicalIF":3.1,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chernozems of Eastern European forest-steppe lowland landscapes: Morphology, classification and spatial distribution","authors":"M.A. Smirnova ,&nbsp;N.I. Lozbenev ,&nbsp;E.A. Levchenko ,&nbsp;P.P. Fil ,&nbsp;D.N. Kozlov","doi":"10.1016/j.geodrs.2025.e00965","DOIUrl":"10.1016/j.geodrs.2025.e00965","url":null,"abstract":"<div><div>The chernozems of the flat interfluves in the Oka-Don Lowland exhibit unique characteristics within the chernozem zone. These soils show distinct signs of groundwater-induced waterlogging in the lower part of soil profile and, unlike the chernozems of elevated plains, do not typically experience summer desiccation. This study is based on an analysis of morphological properties and extensive soil surveys encompassing over 2500 soil profiles across an area exceeding 500,000 ha of the Oka-Don Lowland. The research integrates topographic and lithological factors of soil formation alongside the results of large-scale soil mapping conducted on a 400-ha key site.</div><div>Using machine learning and digital soil mapping techniques, we identified the key environmental drivers governing the spatial distribution of waterlogged chernozems within the Oka-Don Lowland. The key site revealed distinct spatial patterns of chernozem distribution and their associations in catenas with Solonetz, Gleysols, and Stagnosols. Despite the minimal elevation differences across the flat interfluves, topography emerged as the primary factor influencing soil spatial differentiation.</div><div>A comparison of forest-steppe soil classifications between the USSR system and WRB reveals significant discrepancies in their Chernozem categories. For instance, according to the WRB, Chernozems cover 80–90 % of the southern Oka-Don Lowland, whereas the USSR SC classification assigns only 65 % of this area to chernozems. This difference arises because the WRB includes additional soil types in its Chernozem category that the USSR SC classifies differently. Notably, not all soils identified as chernozems in the USSR SC qualify as Chernozems under the WRB; some of them belong to the Phaeozems. Correlating soil taxa at the species level between the USSR SC and WRB results in a loss of critical information regarding soil depth and organic carbon content. This discrepancy can lead to differences of up to 3.5 times in estimates of organic carbon stocks within the 50 cm soil layer.</div><div>These inconsistencies underscore the urgent need to harmonize soil classification data and systematically address these differences when assessing soil organic carbon stocks. Such efforts are essential for ensuring accurate carbon accounting and enhancing our understanding of the role of these soils in the global carbon cycle.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00965"},"PeriodicalIF":3.1,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An evaluation framework for identifying saline croplands for improvement: A case study of Songnen Plain","authors":"Jinyi Huang ,&nbsp;Zhipeng Wu ,&nbsp;Kun Xue ,&nbsp;Junfeng Xiong","doi":"10.1016/j.geodrs.2025.e00963","DOIUrl":"10.1016/j.geodrs.2025.e00963","url":null,"abstract":"<div><div>Land salinisation in the Songnen Plain is a serious constraint to agricultural development. Assessing and identifying saline land as having advantages for improvement is of great significance for improving the efficiency of saline croplands improvement. Taking the western Songnen Plain as the study area, an evaluation framework for identifying saline-alkali croplands for improvement was proposed. Compared with traditional research models that evaluate the degree of saline-alkali land suitable for farming, the purpose of this study is to identify land that is easier to improve and has more or more value for farming. On the basis of evaluating the suitability of saline-alkali land using the Analytic Hierarchy Process-Geographic Information System (AHP-GIS) model, this framework incorporates the degree of soil salinisation, quantified by electrical conductivity and exchangeable sodium percentage, and hydrological connectivity, calculated based on terrain factors and vegetation cover., constructs a saline-alkali land improvement index, and divides suitable improvement areas at different levels. The results indicate that the northern part of the study area exhibits low cropland suitability value, primarily due to higher pH values, unfavorable topography, and lower temperatures. Extreme salinity area are concentrated in the central part of the study area, mainly due to elevated soil conductivity and exchangeable sodium percentages. Areas with high hydrological connectivity value are distributed in the northern, southern, and eastern parts, owing to the presence of numerous lakes and dense vegetation cover. Using the Suitable Improvement Index (SII), 39.42 % of the croplands were identified as suitable for improvement. Among these, low-value, moderate-value, and high-value accounted for approximately 5.43 %, 33.36 %, and 61.21 % of SII subareas. The low SII values are found in Qianan and Tongyu in the southern and central parts of the study area, while high SII values are distributed in Tongyu, Daan, and Taobei in the central part of the study area. The evaluation framework of this study identifies saline-alkali croplands that is more suitable for improvement, providing valuable insights into the restoration of saline-alkali croplands in Northeast China. We provides valuable insights into saline-alkali land restoration from a management and strategic perspective.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00963"},"PeriodicalIF":3.1,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilising soil diagnostic features and environmental covariates to estimate nutrient content in Ethiopian soils","authors":"Gidena T. Reda ,&nbsp;Gerard B.M. Heuvelink ,&nbsp;David P. Wall ,&nbsp;Rogier P.O. Schulte ,&nbsp;Abbadi G. Reda ,&nbsp;Eyasu Elias ,&nbsp;Girmay Gebresamuel ,&nbsp;Rachel E. Creamer","doi":"10.1016/j.geodrs.2025.e00962","DOIUrl":"10.1016/j.geodrs.2025.e00962","url":null,"abstract":"<div><div>Smallholder farmers in Ethiopia generally do not have access to soil testing services for nutrient management planning decisions; as soil analysis is too costly for most farmers. Fertiliser advice is generally accessible via blanket recommendations at a national scale. Hence, an alternative approach is needed to estimate soil nutrient content across the diverse landscapes of Ethiopia. In this study, we propose using diagnostic features to estimate soil nutrient content, which could contribute to the development of fertiliser recommendations. To achieve this the following objectives were defined: (i) to estimate soil nutrient content as influenced by soil diagnostic features; and (ii) to elucidate the influence of environmental covariates and diagnostic features on the estimation of soil nutrient levels in the Ethiopian context. Data from 550 soil profiles, distributed across Ethiopia, were collected from a range of published sources, collated and harmonised. The data were cleaned, and 496 soil profiles were prepared for modelling. To identify which diagnostic characteristics were present across these soils we applied a presence/absence scoring method to identify dominant diagnostic features. Multiple linear regression analyses were used to predict soil chemical properties from the diagnostic features and diagnostic features along with environmental covariates. The performance of the models was evaluated by applying a 10-fold cross-validation using mean error (ME), Lin's concordance correlation coefficient (LCCC), root mean square error (RMSE) and model efficiency coefficient (MEC). The MEC values for pH, TN, and CEC derived from a combination of diagnostic features and environmental covariates were 0.38, 0.33, and 0.38. The corresponding RMSE values were 0.78, 0.07 %, and 13 cmol kg⁻¹. Additionally, the LCCC values for pH, TN, and CEC were 0.62, 0.58, and 0.62, respectively. The cross-validation results for soil chemical properties showed that the model's performance improved when environmental covariates were added. Precipitation, temperature, geology and land cover were the most important environmental covariates for estimating nutrient content, along with diagnostic features of Ethiopian soils. In conclusion, the diagnostic approach offers a useful starting point for estimating soil nutrient content. However, the variation in nutrient content across the six diagnostic features was not adequately quantified, and the model's predictive performance remains insufficient for practical application at the local scale. Further expansion of the dataset is required to fully exploit the potential of these models for underpinning nutrient management decisions across Ethiopia and in other regions where access to soil test information is limited.</div></div>","PeriodicalId":56001,"journal":{"name":"Geoderma Regional","volume":"41 ","pages":"Article e00962"},"PeriodicalIF":3.1,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}