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Soils and landscapes can show complex, non-linear evolution, especially under changing climate or land use. Soil-landscape evolution models (SLEMs) are increasingly equipped to simulate the development of soils and landscapes over long timescales under these changing drivers, but provide large data output that can be difficult to interpret and communicate. New tools are required to analyse and communicate large model output. In this work, I show how spatial and temporal trends in previously published model results can be summarized and conceptualized with evolutionary pathways, which are possible trajectories of the development of soil patterns. Simulated differences in rainfall and land use control progressive or regressive soil development and convergence or divergence of the soil pattern. These changes are illustrated with real-world examples of soil development and soil complexity. The use of evolutionary pathways for analysing the results of SLEMs is not limited to the examples in this paper, but they can be used on a wide variety of soil properties, soil pattern statistics and models. With that, evolutionary pathways provide a promising tool to analyse and communicate soil model output, not only for studying past changes in soils, but also for evaluating future spatial and temporal effects of soil management practices in the context of sustainability.

Environmental monitoring of small, rural watersheds was one of the components of the Natural Resources Management and Rural Poverty Alleviation Program (RS-Rural) in southern Brazil. The purpose of the monitoring was to assess the impact of promoting soil conservation and environment management practices adopted by farmers and funded by the Program. In four small monitored watersheds, in a total of 95 plots representing distinct land use and soil management, surface soil was collected to characterize ground-zero of the Program by determining several soil physical, chemical and microbiological properties. Principal component analysis (PCA) shows soil physical, chemical and biological properties were decisive in defining the agricultural soils in the rural watersheds with family farming. The sensitivity to chemical properties provides an opportunity to improve soil quality if soil management focuses on altering those properties. Soil management practiced by tobacco farmers leads to rapid, intense degradation of some natural soil properties, especially those related to the dynamics of soil organic matter, compared with more conservationist uses (forest, regrowth, and grassland). Thus, soil management must be reoriented to avoid the progress of degradation and recover soil physical and biological quality. Cover crops and by land-abandonment to allow natural vegetation are important management strategies for the degraded soils used for tobacco production, increasing soil organic matter, nutrients and microbial activity and thus allowing further crop production. In conclusion, watersheds with tobacco cropping have soils with lower quality than when under no-tillage grain production, requiring changes in land use and soil management.

This study aimed to determine how crop residue placement and composition would affect soil water content and temperature during the dry season in the central region of Espírito Santo state, Brazil. A 19-week field study was conducted from April to August 2017. A 2 x 4 factorial study with four replications was implemented using a randomized complete block design. Factors were soil management [conventional tillage (CT) and no soil disturbance (ND)] and residue amendment [maize (Zea mays L.), sunn hemp (Crotalaria juncea L.), a maize-sunn hemp mixture, and a no amendment control]. Soil water content and temperature were measured weekly at predetermined soil depth intervals. Soil water content was higher in ND plots amended with surface residues than under all other treatments in the 0 to 0.05 m depth range. All residue amendments in this range were equally effective in conserving soil water. Surface residues reduced soil temperature by up to 8.4 °C relative to the control in ND plots. Incorporating residue amendments by CT cancelled all temperature-moderating benefits provided by surface residues. These results indicate that surface residues from cereals, legumes, or cereal/legume mixtures are equally effective in conserving soil water and moderating soil temperature during the dry season. Additional research is needed to determine how improved soil environmental conditions, generated by surface residues, would affect nutrient acquisition and crop performance. RESUMO Este estudo teve como objetivo determinar como a disposição e composição dos resíduos culturais afetam o teor de água do solo e a temperatura durante a estação seca na região central do estado do Espírito Santo, Brasil. Um estudo de campo de 19 semanas foi conduzido de abril a agosto de 2017, no esquema fatorial 2 x 4 com quatro repetições, em blocos casualizados. Os fatores foram: preparo do solo [preparo convencional (CT) e sem preparo (ND)] e tipos de cobertura [milho (Zea mays L.), crotalária (Crotalaria juncea L.), mistura de crotalária com milho e sem cobertura morta (controle)]. O teor de água e a temperatura do solo foram medidos semanalmente em intervalos de profundidade pré-determinados. A umidade do solo foi maior no NT do que nos demais tratamentos na profundidade de 0-0.05 m. Todas as coberturas mortas nessa profundidade foram igualmente eficazes na conservação da umidade do solo. Os resíduos da superfície reduziram a temperatura do solo em até 8,4 °C em relação ao controle nas parcelas NT. A Incorporação dos resíduos eliminou todos os benefícios de redução de temperatura fornecidos pela manutenção dos resíduos na superfície. Estes resultados indicam que os resíduos superficiais de cereais, leguminosas ou misturas desses são igualmente eficazes na conservação da água do solo e na moderação da temperatura do solo durante a estação seca. Pesquisas adicionais são necessárias para determinar como as melhores condições ambientais do solo, geradas por resíduos de superfície, afetariam a aquisição de nutrientes e o desempenho da cultura.

Soil fertility is one of the crucial factors for agriculture, whose main objective is to increase production. Therefore it is extremely important to know the nutritional requirement of cultivars. Fertility-focused studies are essential for fertilization recommendations in all regions, especially in banana cultivation which is a very demanding plant in fertility. Thus, the present work aimed to evaluate soil fertility, emphasizing the quantification of nutrients necessary to ensure the agricultural productivity of musa sp. The research was developed at laudelino farm, municipality of Teotônio Vilela/Alagoas, between 2019 and 2020, where soil amotragens were performed, randomly collected in the 0-20 cm depth layer, removing 1 kg of soil and sent to the soil laboratory of the Campus of Engineering and Agrarian Sciences (CECA) of the Federal University of Alagoas (UFAL) located in the municipality of Rio Largo-AL, for chemical analysis. The hydrogenic potential (pH), phosphorus (P) and potassium (K+) accessible were analyzed; calcium (Ca+2) and tradable magnesium (Mg+2); saturation by exchangeable aluminum (m%), cation exchange capacity CTC at pH 7.0 (T); base saturation (V%) and; organic matter (OM). As a result of the analysis, the following results were obtained: pH content (5.6); OM (14.1 g/kg) P (5.0 mg/dm³) K (110 mg/dm³), Ca2+ (3.42 cmolc/dm³), Mg2+ (2.53 cmolc/dm³); Al3+ (0.00 cmolc/dm³), H (4.41 cmolc/dm³), and CTC (T) (10.73 cmolc/dm³); m (0.0 %) and V (59 %). Based on the above results, it is suggested the application of 1,103 kg of limestone in order to increase the base saturation to 70%, in addition to the addition of 50 kg/ha of N and 343.5 kg/ha of P2O5 and 96.7 kg/ha of K2O. It is worth mentioning that their applications in the soil must be carried out through sources of 837.8 kg/ha of triple superphosphate; 161.2 kg/ha of potassium chloride and 111 kg/ha of urea. It is also essential to add 30 to 50 t/ha of organic matter, such as bovine manure to the soil, aiming at better utilization of the material by crops.

Context Although both plant cover and mulch are considered for erosion control in arid and semi-arid regions, they have divergent impacts on soil ecology. Aim We examined the effects of orchard floor management practices on the density and diversity of soil free-living nematode communities and relevant soil abiotic properties. Methods Soils were sampled in winter in a citrus orchard in the Sharon region of Israel from plots that for 6 years had been under (1) annual native species; or (2) Avena sativa and Vicia villosa, planted between tree rows; or (3) woodchip mulching along tree rows. There were two control sites: (4) bare soil between tree rows and (5) bare soil along the tree rows (both common practice). Key results Nematode communities and their trophic diversity were significantly impacted by floor management. Significant increases in soil moisture under plant cover, and higher organic matter and water-holding capacity for all covered orchard floors could be related to nematode changes. Shifts in nematode feeding group structure suggest a shift in the type and availability of soil carbon pools. Conclusions There was a strong association between orchard floor management and soil free-living nematode communities, indicating a shift in the soil food-web structure and functionality. Bare soil harboured fewer nematodes, but more complex communities dominated by persisters, while seeded plant cover had a greater nematode abundance dominated by coloniser communities, indicating increased availability of resources. Implications Results reveal the importance of integrating biological information in performance index determinations for improving soil management decisions, suggesting these relationships as sensitive bio-indicators of soil health.

Aims This study looks whether the response of soil management (liming and nitrogen fertilization) on the incidence of Fusarium wilt (Foc Race 1) in Gros Michel banana (Musa AAA) varies with different soil properties. Methods The effect of inoculation with Foc Race 1 was studied in a factorial greenhouse trial with soil samples from eight representative soil types from the Costa Rican banana region, two pH levels; and three levels of N-fertilization. After an 8-week period, plant biomass and a disease index were measured. Results There were significant effects of soil pH and N, and their interactions on disease expression. Low pH levels and high N-fertilization increased the disease expression. The response to changes in soil pH and N-fertilization differed considerably between the different soils. Conclusions Although soil pH and N influence Fusarium wilt in banana, each soil differs in its response to these soil properties. This complicates the development of standard soil management strategies in terms of e.g., N-fertilization and liming to mitigate or fight the disease.

Purpose: Nitrogen (N) cycle is one of the key biogeochemical cycles in terrestrial ecosystems. Global climate change and soil management practices have disrupted the soil N cycling processes due to increased water and N limitations. Biochar is a soil amendment and improves soil–plant water and N retentions. However, it is uncertain to what extent biochar pyrolysis temperature would affect soil N transformations under two soil moisture regimes. This study aimed to explore how pyrolysis temperature would affect biochar properties and subsequently soil N transformations through a short-term laboratory incubation study at two moisture levels. Materials and methods: An incubation study was carried out for 5 days. Biochar added to the soil at a rate of 5% (w/w) was produced under six different pyrolysis temperatures (e.g., 500, 600, 650, 700, 750, and 850 °C). We used 15N natural abundance (δ15N) of inorganic N (NH4+-N and NO3−-N) to assess the potential of biochar materials in facilitating forest soil N transformations at two different soil moisture levels of 50% and 65% water holding capacity (WHC). Results and discussion: Pyrolysis temperature significantly increased cumulative nitrification and N mineralization initially, peaked between 600 and 700 °C and decreased thereafter. However, both cumulative nitrification and N mineralization were significantly lower in the biochar-amended soils than those of the control soil, with significantly lower δ15N of NH4+-N and δ15N of NO3−-N. The 65% WHC had higher cumulative nitrification and N mineralization compared with those in 50% WHC. This study highlights that application of biochar would reduce N losses and improve soil N retention particularly for forest soil. Conclusions: The present study highlights the importance of biochar pyrolysis temperatures for their use as soil conditioner to increase soil N retention. An optimum pyrolysis temperature range of 600–700 °C was identified for improving soil nitrification and N mineralization under the laboratory incubation conditions.

Soil salinity and acidity are the major land degradation processes in coastal agro-ecosystem which harm agricultural productivity. This study aims to evaluate the changes in crop productivity and soil quality of saline and slightly acid soils under the influence of integrated nutrient management (INM) practices. A rice-based strip plot experiment was established on a raised bed created through a land-shaping technique in Coastal Sundarbans of India. Rice-tomato, rice-sunflower, and rice-chili cropping were tested over two consecutive years with the addition of various organic amendments in combination with mineral fertilizers. Soil physical, chemical, and microbial properties were measured using standard protocols. Soil salinity increased during the winter season (crops grown during October to February) hence decreased microbial biomass, soil respiration, and enzyme activities as compared to monsoon (the crop sown at the beginning of the summer rains during June to September). The effect was more pronounced in control. However, the addition of organics reduced the soil salinity and restricted the magnitude of such decreases resulting in higher system rice equivalent yield in those treatments over control. The higher respiratory quotient value was measured in control, indicating a stress response to the loss of more organic carbon. Rice-sunflower cropping and conjunctive use of NPK with green leaf manure + farm yard manure + vermicompost show better performance in terms of soil quality and yield. The application of organic amendments to the soil can be considered an effective management practice, due to soil quality improvement rapidly as well as enhancing microbial activities by reducing soil salinity which is a major problem of coastal saline agro-ecosystem.

Land use and management practices affect the response of soil organic carbon (C) to global change. Process-based models of soil C are useful tools to simulate C dynamics, but it is important to bridge any disconnect that exists between the data used to inform the models and the processes that they depict. To minimise that disconnect, we developed a consistent modelling framework that integrates new spatially explicit soil measurements and data with the Rothamsted carbon model (Roth C) and simulates the response of soil organic C to future climate change across Australia. We compiled publicly available continental-scale datasets and pre-processed, standardised and configured them to the required spatial and temporal resolutions. We then calibrated Roth C and ran simulations to estimate the baseline soil organic C stocks and composition in the 0–0.3 m layer at 4043 sites in cropping, modified grazing, native grazing and natural environments across Australia. We used data on the C fractions, the particulate, mineral-associated and resistant organic C (POC, MAOC and ROC, respectively) to represent the three main C pools in the Roth C model's structure. The model explained 97 %–98 % of the variation in measured total organic C in soils under cropping and grazing and 65 % in soils under natural environments. We optimised the model at each site and experimented with different amounts of C inputs to simulate the potential for C accumulation under constant climate in a 100-year simulation. With an annual increase of 1 Mg C ha−1 in C inputs, the model simulated a potential soil C increase of 13.58 (interquartile range 12.19–15.80), 14.21 (12.38–16.03) and 15.57 (12.07–17.82) Mg C ha−1 under cropping, modified grazing and native grazing and 3.52 (3.15–4.09) Mg C ha−1 under natural environments. With projected future changes in climate (+1.5, 2 and 5.0 ∘C) over 100 years, the simulations showed that soils under natural environments lost the most C, between 3.1 and 4.5 Mg C ha−1, while soils under native grazing lost the least, between 0.4 and 0.7 Mg C ha−1. Soil under cropping lost between 1 and 2.7 Mg C ha−1, while those under modified grazing showed a slight increase with temperature increases of 1.5 ∘C, but with further increases of 2 and 5 ∘C the median loss of TOC was 0.28 and 3.4 Mg C ha−1, respectively. For the different land uses, the changes in the C fractions varied with changes in climate. An empirical assessment of the controls on the C change showed that climate, pH, total N, the C : N ratio and cropping were the most important controls on POC change. Clay content and climate were dominant controls on MAOC change. Consistent and explicit soil organic C simulations improve confidence in the model's estimations, facilitating the development of sustainable soil management under global change.

Abstract This study investigates the adsorption and dissipation of glyphosate and the formation/dissipation of AMPA in non-tilled (NT) and conventionally tilled (CT) soil at 0–5 and 5–20 cm depth. Glyphosate adsorption was mainly related to the different NT and CT soil properties (clay and amorphous Al oxides), whereas an effect of the soil management could not be identified. Glyphosate dissipation was initially fast, and it slowed down later. The initial glyphosate concentration in NT soil at 0–5 cm was significantly lower than the dose applied due to the interception by the weeds and crop residues. AMPA began to form early after treatment and persisted longer than glyphosate. The DT50 range was 8–18 days for glyphosate and 99–250 days for AMPA. Longer glyphosate and AMPA DT50 were observed in NT soil compared to CT soil but, for glyphosate, the difference was significant only at 5–20 cm. Higher glyphosate and AMPA concentrations were detected in NT than in CT soil at the end of the study at 0–5 cm. The differences in glyphosate and AMPA DT50 and persistence were mainly attributable to the influence of different NT and CT soil characteristics. However, other factors could have contributed to the different glyphosate and AMPA dynamics between the soils, like glyphosate wash-off from crop residues on NT soil with the rainfall, the delayed glyphosate return to the soil by weed root exudation or weeds decomposition, and the NT soil compaction which may have reduced the microbial degradation of glyphosate at low concentrations. Graphic abstract

Nitrous oxide (N2O) emissions from soils have been widely studied in the literature — mostly with the chamber method — due to the importance of this gas to climate change. Emissions of N2O derive from biological reactions and are controlled by soil parameters, which are by nature heterogeneous (i.e., “hot spots” for N2O emissions) — a source of uncertainty in chamber-based studies. Spatial variation in N2O fluxes has been assessed in the literature, but the information is still needed for contrasting soil management practices (e.g., tillage) and for specific bioclimatic situations [e.g., non-growing seasons (NGS) under cold weather]. Here, we subsampled daily N2O data to assess within-plot and between-block spatial variation from an agronomic experiment under conventional tillage (CT) and no-tillage (NT), identifying if patterns differ between growing seasons (GS) and NGS datasets. Within-plot spatial variation in N2O fluxes was a small source of uncertainties, but half of the comparisons in GS datasets presented a slope different from 1 for the regression of N2O averages from two vs. one chamber per plot — a source of uncertainty mitigated when within-plot duplication occurred during N2O “hot moments”. Between-block spatial variation in N2O emissions was much larger than within-plot errors — an effect more accentuated for NGS and CT than GS and NT datasets. Decreasing the number of sampled blocks resulted in averages that did not represent the N2O daily average of the whole field, but exceptions occurred. The methodology proposed here may be used in other locations, after appropriate verification, for improved planning and maximization of the resources associated with N2O measurements.

The fate of hydrophilic, hydrophobic, and insoluble fractions extracted from 13C-labelled maize straw and their use for the formation of bacterial and fungal-derived amino sugars (AS) were monitored during a 40-day incubation of upland and paddy soils. The highest sequestration of C in the AS pool was present in the hydrophilic fraction in both soils (1.1–1.4% of input C). Bacterial community in upland soil utilized the hydrophilic fraction the most for the formation of AS, whereas fungi used the hydrophobic fraction, suggesting that bacteria and fungi have different substrate preference. In contrast, fungi used similar portions of all fractions for AS formation in the paddy soil, which could be a substrate utilization strategy under anoxic conditions. Sequestration of microbial-derived C, formed from the added fractions, was lower in paddy than in upland soils (0.7–1.1% vs. 1.2–1.4%), while total AS content showed the opposite trend (493–509 mg kg−1 in paddy vs. 387–405 mg kg−1 in upland soils). This was attributed to the 1.5 times lower microbial activity in paddy than in upland soils based on the relative incorporation of 13C into total MBC. Thus, sequestration of microbial-derived C from various organic C sources is closely related to substrate quality, but soil management and its properties modulate the microbial utilization of substances with various hydrophobicity.

Increasing areas of agricultural land in high rainfall areas of Sub-Saharan Africa (SSA), where crop production used to be reliable, are affected by soil acidity. This review focuses on the extent, causes and effect of soil acidity on soil properties and crop yield and its management from the context of SSA. Studies showed that the detrimental effects of soil acidity can be mitigated through liming, integrated acid soil management and the use of acid-tolerant germplasms. Application of lime resulted in yield increments of 34–252% in wheat, barley and tef, 29–53% in faba bean and soybean, and 42–332% in potato in Ethiopia, 111–182% in maize in Kenya, and 45–103% in Mucuna in Nigeria under moderate to severe acid soil conditions. This was accompanied by a corresponding increase in soil pH up to 1.9 units and a decrease in exchangeable acidity and aluminum up to 2.1 cmol kg−1. Use of acid-tolerant crop varieties such as maize expressing superior tolerance to Al toxicity resulted in a yield increase of 51% under low soil pH in Cameroon and Kenya. Overall, soil acidity covering ∼35% of SSA should be reclaimed with lime and integrated acid soil management interventions, which could significantly increase crop yield and enhance the resilience of the tropical agroecosystems.

The strategy for increasing crop production is either based on bringing new lands under cultivation or through intensive cultivation with improved management practices. Nevertheless, both the strategies require constant monitoring of soil fertility status to avoid nutrient deficiency that is one of the major constraints for crop production and it is a decisive tool for farmers and policy planners in soil nutrient management. The integrated watershed management programme called SUJALA by the watershed department, Karnataka, facilitated to diagnose the soil nutrient status in rainfed areas of Karnataka by collecting soil samples at grid interval from the farmer’s field. A total of 34,011 georeferenced composite samples (0–15 cm) were collected at a 325 × 325 m grid interval to analyse the fertility status of soils. The samples were aggregated under different agro-climatic zones of Karnataka to assess the soil fertility status under each zone. The results showed that per cent sample of low soil organic carbon (

The objective of this work was to evaluate the variation in total and particulate organic carbon contents, carbon vertical stratification, and sensitivity index of organic matter fractions in soils with organic residues arranged in alleys in an agroforestry system, with and without use of fire, in the Caatinga biome, in Brazil. The experiment was conducted in a split-plot arrangement with four replications, with the factor fire in the plots, and the factor organic residues in the subplots. The organic residues used consisted of Gliricidia sepium plants; G. sepium plants and carnauba processing residue; G. sepium plants and bio-compost; and G. sepium plants, carnauba processing residue, and bio-compost, which were evaluated in three soil layers. The alleys with carnauba processing residue, G. sepium plants, and bio-compost presented a better maintenance of particulate, and mineral-associated organic carbon contents. Thus, the agroforestry management in alleys using these three residues was efficient for the maintenance of labile and recalcitrant organic matter compartments. Particulate organic carbon was more sensitive to changes in soil management than total organic matter content, in all alleys, presenting higher sensitivity indexes. O objetivo deste trabalho foi avaliar a variação no carbono orgânico total e particulado, relação de estratificação de C, e índice de sensibilidade dessas frações da MOS sob resíduos orgânicos em aléias em um sistema agroflorestal, com e sem uso do fogo na Caatinga. Por meio de experimento em parcelas subdivididas com quatro repetições, onde nas parcelas foi avaliado o fator fogo, e nas subparcelas foi avaliado o fator resíduos orgânicos nas aléias, com as variações de gliricídia isolada, gliricídia com bagana de carnaúba, gliricídia com biocomposto e gliricídia, bagana de carnaúba e biocomposto, sob três profundidades. Nas aléias com uso combinado dos resíduos da bagana de carnaúba, gliricídia e biocomposto houve maior conservação tanto do conteúdo de C orgânico particulado quanto do C associado aos minerais. Assim, o manejo agroflorestal em aléias utilizando a combinação dos três resíduos foi eficiente na conservação de uma matéria orgânica lábil e mais estável. Verificou-se também que o carbono orgânico particulado em todas as aléias foi mais sensível às modificações realizadas no manejo do solo em relação ao conteúdo total da MOS, no qual observou-se maiores índices de sensibilidade dessa fração. &nbsp

O objetivo deste estudo foi contextualizar trabalhos publicados com manejo de solo e nutrição de plantas e seu efeito sobre a incidência, desenvolvimento do ciclo biológico e danos causados por insetos pragas em agroecossistemas. O manejo de solos e a nutrição de plantas são fatores importantes na determinação de ocorrência de pragas em agroecossistemas. Os solos com adoção de práticas ecológicas de manejo são apontados como fator importante na obtenção de plantas saudáveis. A nutrição de plantas de acordo com as recomendações regionais, aliado a adoção de adubação verde e orgânica, e plantio direto na palha, podem reduzir os surtos de insetos pragas. Dessa forma, as práticas de manejo de pragas devem considerar as intervenções realizadas no solo para reduzir o uso de agrotóxicos em sistema convencional, produção integrada e de insumos ecológicos em agricultura orgânica.

Faba bean is an important food security crop in Southern Ethiopia. Understanding the soil fertility management practices of faba bean farmers could aid in finding a method to replenish soil fertility. However, information on the type and extent of soil fertility management practiced by smallholder faba bean farmers is scarce. Therefore, a study was conducted in the districts of Damot Gale and Sodo Zuria in Wolaita zone in Southern Ethiopia to assess soil fertility management practiced by farmers for faba bean production. In the 2019 main cropping season, 310 farmers were purposively selected by using Yamane’s simplified formula to calculate the sample size and a short structured questionnaire was used to elicit information. The results revealed that faba bean production in the districts studied was constrained by scarcity of arable land that resulted in extensive exploitation of soil nutrients, poor inherent soil fertility, and soil acidity. Poor soil fertility limited grain yield productivity about 57.4%. Additionally, 36.5% of the farm yield was constrained by soil acidity. However, only 27.7% of farms managed the soil by using mineral fertilizers; 32.3% applied farmyard manure, 3.5% used liming, and 2.9% used fallowing. Consequently, the average grain productions of both fertilized and unfertilized faba bean farms were far less than the national average yield of 2.1 t ha-1. The study concluded that soils of the study districts are managed inadequately to enhance their fertility and improve crop yield.

The main cause of flooding and erosion that creates critical land in various regions in Indonesia is surface runoff. The surface runoff will occur if rainfall exceeds the capacity of soil water absorption (infiltration capacity). The soil management of each land use could improve the infiltration capacity. The water movement both on the surface and in the soil determines the water infiltration. This study predicts surface runoff based on the infiltration rate of various land uses and rainfall in the Ciliwung Watershed. A series of studies were performed in the upstream and middle areas of the watershed. Observations of soil properties, water movement, and rainfall were carried out in various dry land uses. The results showed that the soil's physical properties mostly determine the constant infiltration rate, which affected the water movement in the ground. The initial water content, the degree of saturation of the initial moisture content, and the soil's physical properties determine the time of constant infiltration rate. The value of constant rate infiltration and the time of its achievement define the amount of surface runoff that occurs. Keywords: hydraulic conductivity, run off, soil management, time achievement of infiltration capacity

Soil erodibility factor plays essential role in determining how susceptible soil is to hydrological processes such as detachment and removal by rainfall and runoff that could influence soil erosion and sediment entrainment by flooding in an area. This paper therefore determined the erodibility k-value of soil in the Kereke watershed with the purpose of assessing its susceptibility to hydrological processes. Data was collected on some soil properties such as soil texture, soil structure, soil organic matter content, soil carbon content, soil porosity, soil bulk density, soil moisture content and soil erodibility k-value. The systematic sampling procedure was used to select thirty-two settlements which served as catchment areas for data collection; from which thirty-two soil samples were collected for analysis. Tables and graph were used to present the data, and percentages were used to depict variations in the data set. Results of the study shows that the soil samples have high percent sand particles (71.6%), moderate amount of clay particles (15.7%), silt(12.7%), organic carbon (0.6%), organic matter (1.1%), bulk density (1.4 gcm-3 ), porosity (45.2%), moisture content (14.0%) and low soil erodibility k-value of 0.018. The soil erodibility k-value in the study area was considered to be low, and therefore the soils are moderately erodible. This probably accounts for the moderate intensity of soil erosion channels and entrained sediments by flooding observed in the study area. It is therefore recommended that soil management practices should be encouraged by farmers especially planting of cover crops, shifting cultivation and fallowing system. This will allow nutrients gain and improved bulk density to limit soil erodibility capacity and good soil management in the area. Key words: Soil erodibility factor, hydrological processes, Kereke watershed, North Central Nigeria

Organic phosphorus (Po) plays an important role in tropical forest nutrition on strongly-weathered soils. However, of its role in Eucalyptus nutrition little is known. For this purpose, soil P forms were determined by NaOH-Na2EDTA extraction and 31P nuclear magnetic resonance spectroscopy (31P NMR) at 10 sites of Eucalyptus plantations in Brazil. The objectives were (1) to determine the amounts and forms of soil Po; (2) to build a structural model of the soil P cycle to provide quantitative estimates of the transformation processes of soil P. Soil P was found to consist of large amounts of Monoesters-P (on average 43.7 mg kg−1) followed by Diesters-P in the form of DNA (on average 4.2 mg kg−1), as well as containing high reserves of Pi species (on average 101.6 mg kg−1 of the ortho-P; 2.7 mg kg−1 of the pyrophosphate). Thestructural model indicated that the P cycle is regulated by clay, soil organic carbon, total P and pH. High total Po concentrations (on average 48 mg kg−1) reveal a high potential of P supply to Eucalyptus trees, in which Diester-P (DNA) would be the main source P for the available P pool. The close interconnection between ortho-P, pyrophosphate, DNA and Monoester-P compounds provides evidence of a strong influence of soil biological activity on the distribution and accumulation of these P compounds and therefore on the availability of P. Thus, these results are relevant to establish soil fertility management strategies for low-fertilizer input Eucalyptus systems in soils with low fertility.

Soils have shown a negative balance in nutrient budget which poses a great threat to sustainable soil management for increase in growth and crop yield. This study thus investigated the effects of organic and inorganic fertilizers on the growth of Senecio biafrae (Oliv. &Hiern). Topsoil, organic (poultry manure) and inorganic fertilizers (NPK 15:15:15) were used. The fertilizers were weighed and applied to the soil at 5g, 10g, 15g each; control topsoil without application of fertilizers and were replicated five times. Growth parameters including height, number of leaves and stem diameter were taken weekly for the period of the experiment. Application ofpoultry manure and NPK fertilizer had significant effects on all the growth parameters considered. The application of poultry manure resulted into significant increase in the growth parameters towards the latter part of the study. This study has shown that organic manure has great potential for improving soil productivity and plant growth. Keywords: Senecio biafrae, investigate, organic, inorganic, plant yield

Considering human activities are the most direct and important factors leading to the accumulation and loss of soil black carbon (BC), a detailed understanding of soil BC in different functional zones and reasonable soil management are the keys to determine whether soil is the carbon source or carbon sink. In this study, carbon concentrations and isotope compositions of black carbon (BC%, δ13CBC) and organic carbon (OC, δ13COC) were determined in topsoil from different functional zones (roadside grass verges, parks, residential areas, mines, arable lands, woodlands and wastelands) in urban and suburban of Beijing, China. The organic carbon (OC) content in soils of the urban area (averaging 1.67%) is higher than in suburban areas (averaging 1.05%). Black carbon is not evenly distributed across different functional zones, but is more concentrated and variable in urban areas (0.11–2.43%, averaging 0.73%) than in suburban areas (0.03–0.70%, averaging 0.18%). The ratios of BC% to OC% in suburban areas (0.04–0.40) are smaller than in urban areas (0.15–0.98). The δ13CBC of topsoil (–26.35…–20.85‰) reflects that coal combustion has a strong impact on soil BC accumulation in Beijing. The carbon isotope differences between OC and BC of the suburban and urban topsoils are positive (averaging +0.56‰) and negative (averaging –0.41‰), respectively. This suggests that urban areas are seriously influenced by human activities which lead to a large amount of fossil fuel combustion, but suburban areas have received a uniform deposition of atmospherically transported finer BC aerosols.

Process-based biogeochemical models can be used to simulate soil nitrous oxide (N2O) fluxes and maize yields and draw insights on yields improvement and climate change mitigation options. We compared both observed and DeNitrification-DeComposition (DNDC) simulated soil N2O fluxes and maize yields. We used DNDC model to simulate soil N2O fluxes and maize yields under four soil fertility treatments (inorganic fertiliser, animal manure, animal manure + inorganic fertiliser and control,) replicated thrice for 1 year in Central Highlands of Kenya. We sampled soil N2O fluxes using static chambers installed in each plot. We analysed soil N2O using gas chromatography and calculated cumulative fluxes using trapezoidal rule linear interpolation between sampling dates. DNDC showed poor results in simulating daily N2O fluxes (157.16% ≤ normalised root mean square error (nRMSE) ≤ 324.01% and 0.90 ≤ modelling efficiency (NSE) ≤ 0.96), good to excellent performance in simulating cumulative annual soil N2O fluxes (6.16 ≤ nRMSE ≤12.86 and 0.63 ≤ NSE ≤ 0.86) and good to excellent performance in simulating maize yields (1.15% ≤ nRMSE ≤13.86% and 0.51 ≤ NSE ≤ 0.88) across all soil fertility treatments. The DNDC model had good to excellent performance in simulating cumulative soil N2O fluxes and crop yields across treatments. Though the model captured yield-scaled N2O fluxes and N2O emission factors across treatments, they were underestimated under manure treatment. There is a need to continue calibrating the DNDC model for improved capture of daily N2O fluxes and uptakes on Kenyan soils.

Land- use change (LUC) can impact soil quality. In semi- arid areas of Brazil, impacts of LUC need to be understood for better soil management. This study evaluated the impact of LUC on soil organic carbon (SOC), nitrogen (N), and phosphorus (P) dis-tributions through the soil profile and stocks of a Haplic- Cambisol in the Brazilian Semi- arid region. Three land- use systems (LUS) were investigated: agricultural man-agement (30years), regeneration under controlled grazing (25years) after 5years arable management, and native dry forest. Soil contents of P, total C, total N, and N fractions were used to calculate stocks and their stoichiometric ratios for layers 0? 5, 5? 10, 10? 20, and 20? 40cm. Data from these LUS were compared using Kruskal? Wallis non- parametric tests. Changes to soil microbial biomass reflected the sub-stantially reduced SOC concentration and stock in managed soils compared with that of the natural dry forest area. Total N stock was not affected by LUC, although increases in nitrate and ammonium offset a significantly reduced organic N fraction in the agricultural area. The largest P stock was found in agricultural land, followed by the grazed fallow regeneration site. LUC significantly influenced the stoichiomet-ric ratio of C, N, and P, with the change from Caatinga to agriculture affecting the equilibrium between organic residues? input and mineralization. LUC resulted in sig-nificant changes to C, N, and P stocks, which did not recover to the original values, even after 25years of regeneration under controlled grazing. Made available in DSpace on 2022-09-06T15:19:48Z (GMT). No. of bitstreams: 1 Land-use-change-alters-the-stocks-of-carbon-2022.pdf: 1193419 bytes, checksum: d5a93bdbdf54e432529d8c03b583e4aa (MD5) Previous issue date: 2022

A total of 713 research papers about field monitor experiments of heavy metals in farmland and urban soils in China, published from 2000 to 2019, were obtained. A meta-analysis was conducted to evaluate the level of China's heavy metal pollution in soils, mainly focusing on eight heavy metals. It was found that the average concentrations of cadmium (Cd), lead (Pb), zinc (Zn), copper (Cu), mercury (Hg), chromium (Cr), nickel (Ni), and arsenic (As) in China were 0.19, 30.74, 85.86, 25.81, 0.074, 67.37, 27.77 and 8.89 mg/kg, respectively. Compared with the background value (0.097 mg/kg), the Cd content showed a twofold (0.19 mg/kg) rise in farmland soils and a threefold (0.29 mg/kg) rise in urban soils. The decreasing order of the mean Igeo was Cd (1.77) > Pb (0.62) > Zn (0.60) > Cu (0.58) > Hg (0.57) > Cr (0.54) > Ni (0.47) > As (0.28). Nearly 33.54% and 44.65% of sites in farmland and urban soils were polluted with Cd. The average concentrations of eight heavy metals were not sensitive change in recent two decades in farmland and urban soils. The average Pn values for urban (2.52) and farmland (2.15) soils showed that heavy metal pollution in urban soils was more serious than that in farmland, and the middle Yangtze River regions, where industrial activity dominates, were the most polluted. The meta-analysis comprehensively evaluated the current pollution situation of soil heavy metal, and provided important basis for soil management and environment prevention in China.

The spatial variability of soil chemical properties is affected by factors of soil formation and human activities. Understanding their spatial variability will improve agricultural production, reduce environmental problems (e.g., soil pollution, offsite effects), and achieve sustainable agroecosystems. The main objective was to study the spatial variability of pH, soil organic matter, available phosphorus, and available potassium using univariate and multivariate methods in cropland fields in eastern Croatia. For the study, 169 (0-30 cm) soil samples were collected in a 911 ha study area. The results showed that soils had slightly acidic pH, adequate available phosphorus and potassium values for crop production, and low soil organic matter concentration. The variability was high in available phosphorus and low in pH. Soil pH, soil organic matter, available phosphorus, and potassium nugget/sill ratio was 0.00, 2.79, 18.68, and 22.08, respectively. Auxiliary variables increased the accuracy of the predictions. Soil organic matter levels were below the recommendable, and this is very likely an anthropogenic effect, even though the intrinsic process influences soil organic matter. The heterogeneous distribution of phosphorus and potassium highlighted the necessity of fertilization in some areas. For the sustainability of agroecosystems, adaptable site- specific soil management strategies need to be implemented.

Background Hardsetting soils are considered problem soils due to its behavior of becoming hard and unbearable to cultivate not until rewetted. Few investigations were conducted in this kind of problem soil; hence, information about biomass yield and nutrient uptake is still elusive. This study investigated the impact of potentially hardsetting soil on the biomass yield and nutrient uptake of sweet corn under no-tillage cultivation system with varying fertilization treatments. Results The application of full NPK + 1 Mg ha−1 VC increased stover and grain yield by 26–106% and 11–135%, respectively. Approximately 64% and 112% of sweet corn stover and grain yield increased when treated with full NPK. Highly significant quadratic relationship (P P Conclusion Application of organic amendment in combination with inorganic fertilizer could be a sustainable production strategy on sweet corn production system in potentially hardsetting soil under no tillage through enhanced nutrient uptake and biomass accumulation.

Agricultural practices often have persistent effects on soil physicochemical properties and soil biota, which can feedback to influence plant performance. We investigated management-induced differences in soil fertility and soil microbiota for their legacy effects on plant nutrient acquisition and crop/weed competition. Sorghum bicolor (L.) Moench (sorghum), Ambrosia artemisiifolia (L) (ragweed), and Amaranthus powellii S. Wats. (pigweed) were grown as monocultures and mixtures in the greenhouse in soils with distinct management histories. Cross inoculations of sterilized soils were used to quantify biotic vs. abiotic influence on plant growth, nutrient uptake and competitive outcomes. Differences in management history led to a two-fold difference in soil organic matter (OM), and a 37% increase in N acquisition in all species in the high OM soil. The increase in N availability preferentially benefitted pigweed growth at the expense of sorghum. However, microbiota from the high OM soil alleviated the negative effects of pigweed competition on sorghum. Soil management legacy also affected sorghum tiller production and mycorrhizal colonization. Management-induced differences in soil biotic and abiotic factors altered plant performance in a species-specific manner. Management legacy effects on soil microbiota have the potential to increase crop competitiveness against some weed species.

The main purpose of this study was to assess the human health risk of heavy metals in the urban-peri-urban soils from Huelva Township. The soils present high concentrations of potentially toxic elements well beyond the regional screening soil concentration. A site-specific health risk assessment of exposure (oral ingestion, oral inhalation and dermal contact) was conducted according to the regulatory normative. To reduce the uncertainty derived from soil characteristics, bioaccessibility and predicted bioavailability data were included in the assessment. Thereby, in order to evaluate the oral bioaccessibility, a simulation of the gastric condition (pH and T) was applied dissolving the samples in a solution of HCl and 0.4 M glycine. Soils located in industrial areas present higher bioaccessibility than those associated with urban or other uses. The adjusted-relative bioaccessibility total carcinogenic risk for As exceeded the regulatory level in all samples (except samples 7 and 184) indicating that children are more vulnerable, while no detrimental health effects are expected for Pb (except in sample 76, a “greenway” recreational area). The adjusted hazard index for non-carcinogenic effects also overpassed the threshold values in practically all possible scenarios for an adult resident working in Huelva, as well as for a child living and playing in the urban/recreational areas. The main pollutant contributions were related to As and Pb. For this reason, the reported soils exceeding the regulatory levels should be classified as polluted and, therefore, this study should be helpful to initiate necessary soil management interventions to avoid the human health risk.

The spatial modelling of soil properties provides us with essential and useful information relevant to soil fertility management and environmental protection. The study aims to investigate the ability of empirical Bayesian kriging and principal component analysis, multiple linear regressions with environmental covariates in the modelling of soil properties distribution. For this study, thirty (n = 30) soil samples were obtained at 0–30 cm depth and nine (9) soil-environmental covariates derived from the digital elevation model (Shutter Radar Topography Mission at 30 m resolution) in southeastern Nigeria. The summary statistics revealed high sand content (> 70%) which revealed that the soils of the humid tropics developed on the coastal plain parent material are coarse-textured. Pearson correlation matrix revealed a significant but weak correlation between soil properties and soil-environmental variables. Using empirical Bayesian kriging interpolation, the cross-validation results revealed an acceptable prediction for magnesium, potassium, phosphorus, pH and total nitrogen (R2 > 0.5 with RMSE closer to 0). The principal component analysis reveals that principal component 1 to principal component 5 could interpret 78.1% of the total variability of soil properties. Modelling each soil property using multiple linear regression with the derived soil-environmental covariates, the study noted that only magnesium gave the best model fit with 50.9% of the soil-environmental covariates explaining its variability, while other soil properties presented unacceptable models. Therefore, to improve soil property prediction through multiple linear regression, more observation points are recommended to interpret better the performance of multiple linear regression over flat terrain system.

Soil water content (θ) measurement is vital for accurate irrigation scheduling. Electromagnetic induction surveys can be used to map spatial variability of θ when other soil properties are uniform. However, depth-specific θ variations, essential for precision irrigation management, have been less investigated using this method. A quasi-2-dimensional inversion model, capable of inverting apparent soil electrical conductivity (ECa) data to calculate estimates of true electrical conductivity (σ) down the entire soil profile, was developed using ECa data collected by a multi-coil Dualem-421S sensor. The optimal relationships between σ and volumetric water content (θv) were established using all coil arrays of the Dualem-421S, a damping factor of 0.04, an initial model of 35 mSm−1, and with ten iterations (R2 = 0.70, bias = 0.00 cm3cm−3, RMSE = 0.04 cm3cm−3). These relationships were then used to derive soil profile images of these properties, and as expected, θv and σ follow similar trends down the soil profile. The derived soil profile images for θv have potential use for irrigation scheduling to two ECa-derived soil management zones under a variable rate irrigation system at this case study site. They reflect the intrinsic soil differences that occur between texture, texture transitions and drainage characteristics. The method can also be used to guide placement of soil moisture sensors for in-season monitoring of spatio-temporal variations of θv. This soil imaging method showed good potential for predicting 2D depth profiles of soil texture, moisture and drainage characteristics, and supporting soil, plant and irrigation management.

There are still uncertainties regarding the long-term impact of no-tillage farming practices on separate soil functions in the United Kingdom. This paper aimed to evaluate the chemical and physical processes in two different agricultural soils under no-tillage and conventional management practices to determine their impact on water related soil functions at field scale in the United Kingdom. The field-scale monitoring compares two neighboring farms with similar soil and topographic characteristics—one of the farms implemented no-tillage practices in 2013, while the second farm is under conventional soil management with moldboard plowing. Two soil types were evaluated under each farming practice: (1) a free-draining porous limestone, and (2) a lime-rich loamy soil with high silt and clay content. Field monitoring was undertaken over a two-year period and included nutrient analysis of surface and subsurface soil samples, bulk density, soil moisture, infiltration capacity, surface runoff, and analysis of phosphorus (P) and suspended solids in watercourses in close proximity to the test fields. The conversion to no-tillage changed the soil structure, leading to a higher bulk density and soil organic matter content and thereby increasing the soil moisture levels. These changes impacted the denitrification rates, reducing the soil nitrate (NO3) levels. The increased plant material cover under no-tillage increased the levels of soil phosphate (PO43–) and PO43– leaching. The extent to which soil functions were altered by farming practice was influenced by the soil type, with the free-draining porous limestone providing greater benefits under no-tillage in this study. The importance of including soils of different characteristics, texture, and mineralogy in the assessment and monitoring of farming practice is emphasized, and additionally the between field and in-field spatial variability (both across the field and with depth) highlighted the importance of a robust sampling strategy that encompasses a large enough sample to effectively reveal the impact of the farming practice.

It is no doubt that soils are among the Earth’s largest terrestrial reservoirs of carbon pool and hold potential for its sequestration and thus, soils can serve as potential way of mitigating the ever-increasing atmospheric CO2 concentration. However, the stability and flux of soil organic carbon are affected in response to changes that are being driven by forms of environmental and anthropogenic factors. Therefore, to establish carbon sequestration potential of soils, an in-depth scientific evaluation that would provide mapping of and speciation of carbon chemical forms, as well as factors influencing the persistence of carbon in soils are key to the process which are beyond quantitative measurements that are conventionally implemented under different land use and/or soil management. This involves soil chemistry, physics, biology, and microbiology. Hence, this short review communication highlights portions of soil chemistry and physics as well as soil biology and microbiology that have not been given attention in determining and/or underpinning decisions on carbon sequestration potential of soils.

A soil suitability evaluation of Kanamadi South sub-watershed in the Northern Dry Zone of India was undertaken in the present study to define the soil fitness for the production of maize, pearl millet, and sorghum, the three major kinds of cereal that are widely grown in the area. The soils of Kanamadi south sub watershed were grouped into 19 mapping units. The mapping units of the study area were moderately (S2) to marginally suitable (S3) for maize. The suitability of the study area for pearl millet was found to be highly suitable (S1) to marginal (S3) suitable for pearl millet. The mapping units of the study area were high to marginally suitable for growing sorghum. Appropriate soil fertility management recommendations through an integrated soil fertility management approach should be applied to address these limitations as their lack of attention could affect the availability and uptake of nutrients by these crops in the study area.

Land degradation is a threat to biodiversity and has negative impacts on agricultural communities by aggravating food insecurity. The objective of this study was to examine the responses of native woody species and soil variables to different levels of glacis degradation in the Sahelian zone of Burkina Faso. Field investigations were performed according to the degradation gradient outlined in the Braun-Blanquet method. Soil samples were collected and analyzed in the laboratory. The results indicate that the diversity and diametric structure of woody species are functions of the glacis degradation stage. A total of eight (08) woody species were recorded on the glacis (7 species in non-degraded glacis, 7 species in moderately-degraded glacis and only 1 species in degraded glacis). Acacia raddiana is the only local woody species present in all three glacis degradation stages. It is recommended to rehabilitate degraded glacis in the Sahel in response to desertification. The high levels of sand, nitrogen (N) and carbon (C) characterize the non-degraded and moderately-degraded glacis, whereas the high levels of silt, clay, bulk density, pH-H20 and pH-Kcl indicate degraded glacis. This study can inform the future rehabilitation and management of Sahelian glacis.

Mapping the spatial distribution of soil fertility in a particular area gives an idea about the nutrient content in the soil which plays an im-portant role in fertilizer recommendation, sustainable soil manage-ment, integrated plant nutrient management, landuse planning, and site-specific nutrient management (SSNM). A study was carried out to assess the soil fertility status of the Rapti Municipality, Chitwan, Ne-pal. A total of 120 soil samples was collected based on land use, slope, and aspects with the useof Google Earth Pro (GEP) and ArcGIS. Based on the soil test report spatial variation of soil texture, soil pH, total nitrogen, available phosphorous, and potassium of the study area was prepared. The majority of the study area (57.11%) has sandy clay soils. The soil pH was very strongly acidic to slightly alkaline with pH values ranging from 4.8 to 8.0. Soil organic matter (1.94-3.75%), total nitrogen (0.097-0.187%), available phosphorous(51.03-270.10 kgha-1), and available potassium (169.87-358.68 kgha-1) in the soil are within the range of medium to high in the study area. To maintain this nutrient status, the use of organic manure, reduced use of chemical fertilizers, and different soil management practices should be adopted in this area.

In recent years, common bean in Brazil has become interesting to precede the growing of off-season cotton due to its short cycle. This study was carried out in a Red Latosol in Chapadão do Sul, MS and aimed to select among the attributes of the evaluated soils, those with the best linear and spatial correlation, to explain the variability of grain yield of common bean in the soil layers of 0 - 0.10 m (layer 1) and 0.10 - 0.20 m (layer 2), sampled in a grid of 121 georeferenced points (spacing of 5 meters between points). The soil chemical attributes were determined: pH, carbon (C), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum (Al), and the sum of bases (SB). The analysis of these data was carried out using statistical and geostatistical techniques that made it possible to verify that for the grain yield of common bean, the multiple regression analysis indicates that approximately 20% of its variation is attributed to the variation in the chemical attributes of the soil presented in the present study. The chemical attributes pH1, pH2, C1, Ca1, Ca2, Mg1a, Mg2, Al2, SB1, and SB2 have spatial dependence classified mostly as moderate. Both linearly and spatially, C1 stood out as a potential indicator of common bean grain yield when grown under no-tillage.

Understanding topography effects and assessing the soil properties in different land use is an essential first step for sustainable soil management. Hence, land use type and altitudinal gradient on selected soil parameters were studied in Ayiba watershed, northern Ethiopia. Thirty composite soil samples were collected from 0 to 30 cm of soil depth under four land use types across three altitudinal gradients and were analyzed for selected soil parameters following the standard procedures. A significant main effect of land use and altitudinal gradient on the content of the soil particles was noted. Results also indicated that the bulk density (BD), total porosity (TP), and Pav of the soil are significantly different ( p p p

A pilot area south El-Amiria, Alexandria Governorate, Egypt was studied by using remote sensing techniques to define its main physiographic units. The soil studies were carried out by two classification systems; USDA (USDA, 2014) and FAO (FAO, 2006 b). The area locates between longitudes 29o47`55``and 30o 30`05`` East and latitudes 29o29`30`` and 30o30` 05`` North and comprise an area of about 571168 Feddan. Two physiographic units were recognized in the studied area as follows: I) Lacustrine plains, which includes four sub-units differ in their soil depths, i.e., moderately deep, deep, very deep, and rock outcrops. 2)Windblown sand, which includes three sub-units, i.e.sand sheets soils, BarchanDunes and Barchan dunes with partial CaCO3 cementations. By comparing the two systems of soil classification used in this study, it is observed that FAO system (FAO, 2006 b) includes different levels of soil properties which have a direct effect on soil reclamation, suitability and land use. On the other hand, USDA system (USDA, 2014) gives importance for texture, mineralogy, soil temperature …etc. in family level which adds more detailed information for soil management. Consequently, applications of the two classification systems, is necessary or preferable due to their compilation.

Agriculture 3.0 and Agriculture 4.0 requires appropriate agricultural practices, including soil data that are practical, accurate, and easy to understand. Using soil type maps and land suitability class maps for soil information not only challenges users but also does not provide soil quality information such as production potential and plant growth and production inhibitors. Other techniques that can provide more appropriate soil information for agricultural purposes are thus needed. This research suggests the soil assessment system Soil Quality Index Plus, which provides accessible information regarding soil conditions and plant growth and production inhibitors in the context of dryland farming. Field trials were conducted in 36 locations across five regencies in West Java, Indonesia. Soil Quality Index Plus accurately assessed soil quality by using 11 key parameters as a dataset: effective depth, texture class, bulk density, drainage, pH, cation exchange capacity, total organic nitrogen, available phosphate, exchangeable potassium, aluminum saturation, and total carbon organic. The majority of the soils studied were classified as medium soil quality, with low organic carbon being the most common limiting factor. Improved fertilizer management, especially the use of organic fertilizers, phosphate- and nitrogen-based fertilizers, and agricultural lime should be implemented in particular areas.

Evaluation of the spatial and temporal composition of floodplain sediments and soils is critical in the creation of soil management strategies for impacted riverine catchments. The objective of this study was to determine the distribution, and to identify the sources, of particulate trace elements and fallout radionuclides in the catchment of the River Avon (SW England), where sedimentary processes had been altered by reservoir construction in the 1950s. The catchment was compartmentalized into its main functional units namely, cultivated land, pasture, woodland, wet moorland, and channel bank. Surface soils were collected in each unit, along with four strategically-placed cores, all of which were analyzed for particle size, fallout radionuclides and elemental concentrations. Sediment particle sizes and sediment accumulation rates were affected by the construction of the reservoir, specifically the distributions of silt and clay. The concentrations of fertilizer constituent Cr and P were highly correlated in the mid-catchment but were unrelated downstream due to elevated concentrations of Cr from geological deposits. Copper, As, Pb and Sn had variable down-core distributions, with pulses in concentrations due to mining inputs. The contributions of the end-member sources of particulate elements in the sedimentary mixtures were evaluated, quantitatively, using a Bayesian Mixing Model and the cultivated land was identified as a significant contributor to the mixtures, independent of space and time. The results contribute to advances in soil quality and conservation measures as components of a catchment management plan for the Avon, an approach maybe applicable to other small catchments in the UK and internationally.

A remarkable decrease in olive production has been observed in Tunisia since 2000, particularly in the semi-arid region. This downfall was mainly due to a notable change in climatic conditions as a result of wind erosion and over cultivation. The aim of this work was to study the biological, physical, and chemical properties of several semi-arid soils from olive tree fields subjected to different farming practices, such as crop time and type of crop, olive mill wastewater (OMW) application rates, and tillage timing and depth (deep or conventional plowing). We noted that hydraulic conductivity (HC) was proportional to the age of the soil tillage, and the highest values were recorded in the soil cultivated for 100 years, with an average value of 33.05 ± 0.02 mm h−1. An important increment of the iron soil content was observed, especially after the fig tree introduction among the olive trees (12,094 ng μL−1) in 2007. Also, a significant increase of the organic matter (OM) content (up to2.6 mg-OM/g-soil) was identified in soil treated with OMW compared to the lowest OM content (0.83 mg-OM/g-soil) recorded in the soil cultivated since 1901. The bacterial communities of the different soils were characterized by 454 pyrosequencing technology, and showed an important diversity, mainly corresponding to Proteobacteria, Actinobacteria, and Acidobacteria. Many operational taxonomic units (OTUs) are raretons, indicating a high resilience of the soil bacterial communities. Statistical analyses showed significant correlations with the different soil parameters. However, an unexpected correlation was determined between soil respiration and OM (r = − 0.583*), suggesting that OM increases the retention of CO2, a greenhouse gas. The farming techniques analyzed in this study resulted in a reduction of the bacterial diversity, even though the total bacterial biomass augmented.

One of the strategies for the recovery of degraded soils is the planting of fast-growing forage species with high biomass production. In this sense, the objective of this research was to evaluate the initial growth of sorghum in degraded soils with organic fertilization and different phosphorus levels. A completely randomized design with a 4 x 3 x 2 factorial arrangement was used, with four soil types, three levels of phosphorus fertilization and two levels of organic fertilization. At 64 days after sowing the characteristics of the initial growth were analyzed: plant height, stem diameter, leaf number and fresh shoot mass. The height was measured by measuring the neck of the plant until the end of the newest fully expanded leaf, measured with the aid of a measuring tape and expressed in centimeters. The diameter of the stem, by means of a digital pachymeter. The application of phosphorus and organic matter in degraded soils is necessary for the initial development of sorghum plants, due to the low availability of this element, caused by the high adsorption of P in the soil colloids. Besides that, the lack of organic matter in the studied soils led to a decrease in the growth of sorghum, therefore, it is concluded that soil management in saline environments is necessary for the application of phosphorus and organic matter for a sustainable and technically viable production.