Exchangeable Ca Research Articles

Adaptive changes in immunological, hematological and metabolic profiles of pregnant cows

Pregnancy triggers a series of complex interactions within the body, involving both the immune system and metabolic processes. In the case of pregnant cows, these mechanisms are essential for supporting the developing fetus and maintaining the overall health of the mother. The aim of the work was to study the hematological, biochemical, and immunological parameters of cows at different periods of pregnancy. Research was conducted on cows (Bos Taurus) of the Ukrainian Black-and-White dairy breed. Groups were formed based on the principle of analogs. The research was carried out using the methodology of group-period experiments. The control group consisted of non-pregnant cows. The first observation period was conducted on pregnant cows with confirmed pregnancy (30 days). The second observation period was carried out at 90 days of pregnancy, the third at 180 days of gestation, and the fourth at 270 days. Laboratory studies included immunological research conducted in the specialized laboratory of immunology for reproduction animals. The first notable observation was the gradual increase in the population of CD3+ lymphocytes from the beginning of gestation, which remained stable until the 90th day of pregnancy and then gradually decreased. The population of B cell immune cells CD22+ had its peculiarities: dynamic and stable growth from the start of pregnancy until the middle of the second trimester (180 days), followed by a gradual decrease until the onset of labor. The redistribution of T and B lymphocytes occurred with dynamic fluctuations in the number of undifferentiated 0-lymphocytes. The processes of transformation and adaptation of homeostasis affected both enzyme activity and indicators of mineral metabolism. Thus, from the beginning of pregnancy (from the 30th day of gestation), the experimental cows showed a significant increase in alkaline phosphatase activity (P < 0.05), alanine aminotransferase (P < 0.05), and aspartate aminotransferase activity (P < 0.05). During the pregnancy of cows, body changes occur. From the early period of gestation throughout the entire period of embryogenesis, changes in the system of hematopoiesis, alterations in the activity of enzymes, exchange of Ca and P, accompanied by changes in immunological reactions take place. These processes are adaptive and ensure the maintenance of the homeostasis system. The perspective of further research will aim at studying changes in immunological and biochemical parameters during physiological pregnancy and when it is complicated.

Variations in the quantity and chemical composition of soil dissolved organic matter along a chronosequence of wolfberry plantations in an arid area of Northwest China

Abstract Background Dissolved organic matter (DOM) is the most active component of soil organic matter (SOM), playing a major role in regulating soil fertility and carbon cycling. However, the effects of different wolfberry (Lycium barbarum L.) planting ages on the chemical diversity of DOM and its interaction with soil physicochemical properties have not been comprehensively studied. In this context, we collected soil samples (0–10 cm) from wolfberry orchards at different planting ages (1, 4, 6, 10, and 13 years) and from a corn field (0 years) in the arid region of Northwest Ningxia in China to assess the changes in soil DOM quantity and quality using ultraviolet–visible absorbance, fluorescence spectroscopy, and parallel factor analysis. Results We found that the ages of the wolfberry plantation changed the contents of soil nutrients and SOM. In addition, significantly higher DOM concentrations were observed at wolfberry planting ages of 10 and 13 years than those in the control group (0 years) by 176.6 and 190.2%, respectively. The specific ultraviolet absorbance at 254 nm (SUVA254) and 254 nm to 365 nm ultraviolet absorbance ratio (E2/E3) values were decreased and increased, respectively, after wolfberry planting, indicating low aromatic and molecular weight compounds of soil DOM. The biogenic index (BIX) and fluorescence index (FI) of soil DOM ranged from 0.6 to 0.7 and 1.42 to 1.93, respectively, suggesting a combination of allochthonous and autochthonous sources. The short- and long-term wolfberry cultivations of 1 and 4 years decreased and increased the humification degrees of soil DOM, respectively. The contribution rate of the protein-like (C1) fluorescence intensity decreased, while that of the fulvic acid-like component (C3) increased with increasing wolfberry planting age, suggesting a change in the structure of soil DOM from protein-like to fulvic acids. In this study, total nitrogen (TN) and exchangeable Ca2+ were the main factors affecting the quantity and quality of soil DOM in the wolfberry orchards with different planting ages. Conclusions This study demonstrated that long-term wolfberry plantation enhances the accumulation of soil DOM and more complex compounds, thereby promoting soil organic carbon sequestration under different planting ages and land-use types in terrestrial ecosystems. Graphical Abstract

Nitrogen deposition caused higher increases in plant-derived organic carbon than microbial-derived organic carbon in forest soils

Plant- and microbial-derived organic carbon, two components of the soil organic carbon (SOC) pool in terrestrial ecosystems, are regulated by increased atmospheric nitrogen (N) deposition. However, the spatial patterns and driving factors of the responses of plant- and microbial-derived SOC to N deposition in forests are not clear, which hinders our understanding of SOC sequestration. In this study, we explored the spatial patterns of plant- and microbial-derived SOC, and their responses to N addition and elucidated their underlying mechanisms in forest soils receiving N addition at four sites with various soil and climate conditions. Plant- and microbial-derived SOC were quantified using lignin phenols and amino sugars, respectively. N addition increased the total microbial residues by 20.5% on average ranging from 9.4% to 34.0% in temperate forests but not in tropical forests, and the increase was mainly derived from fungal residues. Lignin phenols increased more in temperate forests (average of 63.8%) than in tropical forests (average of 15.7%) following N addition. The ratio of total amino sugars to lignin phenols was higher in temperate forests than in tropical forests and decreased with N addition in temperate forests. N addition mainly regulated soil microbial residues by affecting pH, SOC, exchangeable Ca2+, gram-negative bacteria biomass, and the C:N ratio, while it mainly had indirect effects on lignin phenols by altering SOC, soil C:N ratio, and gram-negative bacteria biomass. Overall, our findings suggested that N deposition caused a greater increase in plant-derived SOC than in microbial-derived SOC and that plant-derived SOC would have a more important role in sequestering SOC under increasing N deposition in forest ecosystems, particularly in temperate forests.

Site Quality for Araucaria angustifolia Plantations with Subtropical Cambisol Is Driven by Soil Organism Assemblage and the Litter and Soil Compartments

Different site quality levels in Araucaria angustifolia (Bert.) O. Kuntze plantations may influence the soil organisms and the interaction between litter and soil chemical properties by providing habitats and nutrients in different pathways. Our aim here was to understand the effect of site quality level in the interaction among litter, soil–solid phase, and organism assemblage on A. angustifolia, Campo Belo de Sul, Santa Catarina, Southern Brazil. In the low site quality, the litter deposition, litter K content, litter Ca content, soil organic matter, soil P content, soil K content, and soil exchangeable Ca reduced by 50.50, 49.54, 11.89, 20.51, 11.74, 61.18, and 35.18%, respectively, when compared to the high site quality. Nonmetric multidimensional scaling (NMDS) grouped the influence of site quality degree into three groups, considering the dissimilarities among soil organisms. The ordination of the soil organisms, richness, and Shannon’s diversity in each studied site quality degree had a stress value of 0.08. The structural equation models showed that the loss of site quality had a negative relationship with soil organism assemblage and soil and litter compartments. Our study highlights the fact that a fertile soil, a soil enriched in organisms, and enough litter support the forest productivity.

Distribution of exchangeable Ca2+ during the process of Larix decidua Mill. pollination and germination

The involvement of Ca2+ ions in angiosperms sexual processes is well established, while in gymnosperms, such knowledge remains limited and is still a topic of discussion. In this study, we focused on Larix decidua, using Alizarin-red S staining and the pyroantimonate method to examine the tissue and subcellular distribution of free and loosely bound Ca2+ ions at different stages of the male gametophyte's development and its interaction with the ovule. Our findings show that in larch, both the germination of pollen grains and the growth of pollen tubes occur in an environment rich in Ca2+. These ions play a crucial role in the adhesion of the pollen grain to the stigmatic tip and its subsequent movement to the micropylar canal. There is a significant presence of free and loosely bound Ca2+ ions in both the fluid of the micropylar canal and the extracellular matrix of the nucellus. As the pollen tube extends through the nucellus, we observed a notable accumulation of Ca2+ ions just above the entry to the mature archegonium, a region likely crucial for the male gametophyte's directional growth. Meanwhile, the localized presence of free and loosely bound Ca2+ ions within the egg cell cytoplasm may inhibit the pollen tubes growth and rupture, playing an important role in fertilization.

Eastern Canadian boreal forest soil and foliar chemistry show evidence of resilience to long-term nitrogen addition.

The boreal forest is one of the world's largest terrestrial biome and plays crucial roles in global biogeochemical cycles, such as carbon (C) sequestration in vegetation and soil. However, the impacts of decades of N deposition on N-limited ecosystems, like the eastern Canadian boreal forest, remain unclear. For 13 years, N deposition was simulated by periodically adding ammonium nitrate on soils of two boreal coniferous forests (i.e., balsam fir and black spruce) of eastern Canada, at low (LN) and high (HN) rates, corresponding to 3 and 10 times the ambient N deposition, respectively. We show that more than a decade of N addition had no strong effects on mineral soil C, N, P, and cation concentrations and on foliar total Ca, K, Mg, and Mn concentrations. In organic soil, C stock was not affected by N addition while N stock increased, and exchangeable Ca2+ and Mg2+ decreased at the balsam fir site under HN treatment. At both sites, LN treatment had nearly no impact on foliage and soil chemistry but foliar N and N:P significantly increased under HN treatment, potentially leading to foliar nutrient imbalance. Overall, our work indicates that, in the eastern Canadian boreal forest, soil and foliar nutrient concentrations and stocks are resilient to increasing N deposition potentially because, in the context of N limitation, extra N would be rapidly immobilized by soil micro-organisms and vegetation. These findings could improve modeling future boreal forest soil C stocks and biomass growth and could help in planning forest management strategies in eastern Canada.

Soil warming affects sap flow and stomatal gas exchange through altering functional traits in a subtropical forest

Climate warming influences the structure and function of ecosystems. However, the mechanisms of plant water use and gas exchange responses to climate warming have been less studied, especially from the perspective of different functional traits. We conducted a field experiment to investigate how soil warming (+2 °C) affects sap flow and stomatal gas exchange through plant functional traits and nutrient characteristics in a subtropical forest. We measured stomatal gas exchange of trees (Acacia auriculiformis and Schima superba) and shrubs (Castanea henryi and Psychotria asiatica), and monitored long-term sap flow of both tree species. Besides, plant leaf nutrient contents, functional traits, and soil nutrients were also studied. It is demonstrated that soil warming significantly increased maximum sap flow density (Js_max, 35.1 %) and whole-tree transpiration (EL, 46.0 %) of A. auriculiformis, but decreased those of S. superba (15.6 % and 14.9 %, respectively). Warming increased the photosynthetic rate of P. asiatica (18.0 %) and water use efficiency of S. superba (47.2 %). Leaf nutrients and stomatal anatomical characteristics of shrubs were less affected by soil warming. Soil warming increased (+42.7 %) leaf K content of A. auriculiformis in dry season. Decomposition of soil total carbon, total nitrogen, and available nitrogen was accelerated under soil warming, and soil exchangeable Ca2+ and Mg2+ were decreased. Trees changed stomatal and anatomic traits to adapt to soil warming, while shrubs altered leaf water content and specific leaf area under soil warming. Warming had a greater effect on sap flow of trees, as well as on their leaf gas exchange (total effect: −0.27) than on that of shrubs (total effect: 0.06). In summary, our results suggest that the combination of functional and nutrient traits can help to better understand plant water use and gas exchange responses under climate warming.

Effect of Pruning in Coffee-Based Agroforestry System on Soil Chemical Properties

The low coffee productivity in smallholder coffee-based agroforestry systems and soil fertility degradation indicate mismanagement in soil and plant systems. The study examined pruning management practices on soil chemical properties in smallholder coffee agroforestry systems. Different pruning management were examined on UB forest coffee-pine agroforestry, namely pruned pine and unpruned coffee (T1), unpruned pine and pruned coffee (T2), and unpruned pine and unpruned coffee (T3). Each treatment has four replications, a total of 12 plots (size 2×3 meters for each plot). Soil samples were taken from five sampling points in each plot, ranged between 0-50 cm from the coffee stems at two different soil depths (ie, 0-20 cm and 20-40 cm) in each plot. Unpruned pine and coffee pruned (T2) plots had 21% to 61% higher total N at 20-40 cm soil depth than the other plots. Meanwhile, total K, soil exchangeable K and Na were higher from 21% to 335% in plots with pine and coffee without pruning (T1) as compared to unpruned pine with pruned coffee (T2) and pine and coffee without pruning (T3), preferably at 0-20 cm soil depth. Lastly, the unpruned pine and unpruned coffee management (T3) had 98% to 162% higher soil exchangeable Ca and Mg at a depth of 0-20 cm as compared to the other plots. The study suggests that tree management can affect soil chemistry. The study also found differences in litter input and microclimate (i.e., temperature, moisture and humidity levels, both on soil and air) between plots which are potentially affected by decomposition rate of soil organic matter and nutrient mineralization.

Assessment and Mapping of Soil Fertility Status of Migna Kura Kebele, Wayu Tuka District, East Wollega, Oromia, Ethiopia

Soil fertility decline is a significant obstacle to Ethiopia's increased food production, but information on current soil fertility status among the study areas is inadequate. Accurate soil fertility data is crucial for implementing effective strategies and developing targeted interventions to improve agricultural productivity and food security in Ethiopia. This study was initiated in this context with the aim of mapping the spatial distribution of specific soil parameters and assessing the status of soil fertility in Migna Kura Kebele, Wayu Tuka District, East Wollega, Ethiopia, providing crucial information for agrarian development. A total of 32 samples of surface soil were drawn at Stratifying random for laboratory analysis in 2019 G.C. Maps of soil fertility status were created using ArcGIS 10.4.1 and the common Kriging interpolation technique. Clay loam and clay are the two types of soil in the research study area. The bulk density of the soil ranged from 1.13 to 1.46 g/cm3, while the total porosity ranged from 42.57 to 55.15%. The pH of the soil can range from 6.7, which is slightly acidic, to 4.91, which is strongly acidic. The range of soil exchangeable acidity levels was 0 to 2.46 cmol (+) kg-1, while the range of OC values was medium (1.79% to 3.51%). Soil total N and available P values were between very low and low (0.19 to 1.11%) and 6.71 to 13.44 mg kg-1, respectively. Exchangeable Ca, Mg, K, and Na levels in the soil ranged from 6.93 to 51.15, 2.85 to 23.63, 0.21 to 1.76, and 0.05 to 0.71 cmol (+) kg-1, respectively, while a medium to very high degree of CEC (22.19 to 77.42 cmol (+) kg-1) was observed. A moderate to very high rating was assigned to soil PBS, which ranged from 42.13 to 98.30%. Micro nutrients; Fe, Mn, Cu, and Zn extractable from soil by DTPA ranged in value from 12.07 to 33.51 mg kg-1, 16.02 to 48.26 mg kg-1, 0.18 to 0.62 mg kg-1, and 0.19 to 0.62 mg kg-1, respectively. The soil fertility map was created for the following parameters: pH, OC, total N, available (P, S), CEC, PBS, Ca, Mg, Fe, and Mn; Cu, Zn, and B. According to the study's findings, the study area's soils were found to be deficient in six nutrients that limit yields: N, P, K, S, B, and Zn. he soil in the study area is affected by soil acidity; for sustainable crop production in the study area, soils should be amended with lime, organic matter, and fertilizers of N, P, S, K, B, and Zn.

Impact of biochar from different agricultural wastes on soil chemical characteristics and growth of maize

The use of biochar as soil amendment is gaining acceptance as an important management strategy to tackle food insecurity for the growing population in Nigeria amid soil deterioration. This study examined the influence of biochar produced from the different agricultural wastes on soil chemical characteristics and growth of maize. A pot experiment was conducted at the greenhouse of Imo State University Owerri, Nigeria. The experiment was laid out in completely randomized design. The agricultural wastes used were rice husk, corn cob, poultry manure and pig dung. The agricultural wastes were charred differently for 60 minutes at the temperature of 250oC. The maize plant used for the experiment was Oba super II. The biochar was produced using modified biochar kiln and were applied to the soil at the rate of 10t ha-1. The treatments were replicated thrice. Soil amended with poultry manure charred for 60 minutes at 250oC (PMB60) had the highest significant growth (plant height) and yield (dry matter) parameters. Significant differences were observed among the biochar amendments with the soil chemical characteristics (pH, Available P, SOM, TN, Exchangeable base cations and CEC). However, the study reported that PMB60 gave the highest significant increase in almost all the soil chemical characteristics (soil pH(6.0), Avail. P(18.20mg kg-1), exchangeable Ca(5.8Cmol kg-1), Mg(3.97Cmol kg-1, K(0.32Cmol kg-1, Na(0.28Cmol kg-1) and CEC(10.75Cmol kg-1)) compared to the other biochar amendments. This study concluded that PMB60 was better suited to improve soil chemical characteristics while also improving maize performance compared to the other biochar amendments.

Geospatial Variability of Soil Properties of the Different Villages in Arajiline Block of Varanasi District of Uttar Pradesh

The current study was conducted at the different villages of the Arajiline block of Varanasi district, Uttar Pradesh, India during November, 2022–June, 2023 to evaluate the variability of soil properties and nutrient indexof soils. The random sampling technique was used to collect 40 soil samples at different locations with the help of GPS at 0–15 cm depth. The collected soil samples were air-dried in shade at room temperature, passed through a 2 mm filter paper, and analyzed for different physico-chemical properties. The result revealed that the TS (range 8.2–81.3%), VFS (range 4.2–35.5%), Silt (range 10.1–54.2%), Clay (range 7.7–38.8%), BD (range 1.08–1.45 g cm-3), PD (range 2.04–2.33), Porosity (range 30.24–51.56%) pH (range 6.4-7.8), EC (range 0.1-0.3 dS m-1), OC (0.2-0.6%), and available N, P, K, S, Ca, and Mg varied from 130.12–260.30 kg ha-1, 14.2-23.2 kg ha-1, 145.0–240.0 kg ha-1, 7.5–17.6 kg ha-1, 3.8–8.2 cmol(P+)/kg, and 2.1-4.1 cmol(P+)/kg, respectively. The findings indicated that the studied soils were slightly acidic to moderately acidic and free from salinity hazards; 70% of the soil samples were low in organic carbon, 30% were medium in organic carbon, and 100% of the soil samples were low in available N and medium in available P, K, and S. 100% of soil samples were found to be sufficient in exchangeable Ca and Mg. The findings of this research could help in crop nutrient management, fertilizer recommendation, and decision-making for increasing agricultural production and farmer profitability.

Effect of Incubation of Biochars Amendment on the Chemical Properties of Acidic Soil

Biochar is considered as universal conditioner to improve soil quality, but its effect on different soil types and rates on soil properties,bacterial community and plant growth are still unclear,particularly in the typical acid soil in southeastern Nigeria. This study was done to know the changes in soil chemical composition which could be caused by dissolution and release of nutrients from biochar in an incubation experiment. The study was conducted during rainy season in 2022 in Sobioma Agro Farms LTD using loamy sand with acidic pH (5.7). The soil were collected from the same farm. Soil was filled in separate plastic bucket with lid (2kg capacity) and treatments imposed as per the treatment details; T1: Corn Cob charred for 60 minutes @ 20 t ha-1 T2: Rice husk charred for 60 minutes @ 20 t ha -1 and T3: Poultry manure charred for 60 minutes @ 20 t ha-1. The treatments were replicated thrice, then repeated for different days of incubation (15,30 and 45days respectively). The experiment was laid out in a completely randomized design (CRD). In this study, the biochar carbon content and Total N ranges from 95.9 to 181.4 gkg" 1 and 5.2 to 8.9 gkg' 1 respectively with the highest values on rice husk biochar (Table 3). Poultry manure showed highest significant (P O.05) effect in Cu (1.61 mgkg- 1), Mn (5.26 mgkg- 1 ) and Fe (6.54 mgkg 1 ) compared to rice husk biochar and corn cob biochar (Table 4). The Cations Exchange Capacity (CEC) and base saturation (BS) increased after amendment of the acidic soil with PMB (5.51 cmolkg' 1 and 85.4% respectively).
 The results revealed that, application of different biochar increased the pH and other soil chemical properties evaluated with slight increase only in exchangeable k and Na and a decrease in exchange acidity (A l and H) of soil. During the incubation experiment changes were noticed, some nutrient element showed a continuous increase with incubation time (exchangeable Al and H in Corn cob and poultry manure biochar respectively) while some reached its maximum at the mid incubation time (CEC, BS, TN, Av.P and OM in poultry manure biochar). In some cases a decline was observed up to the mid incubation period after which an increase was observed (Exchangeable Ca and Mg in corn cob biorchar and Exchangeable k and Na in Rice husk buiochar). This work stresses the importance of biochar to soil quality improvement.

Assessment of Soil Fertility Status in Selected Fields under Maize Production in Kongwa District, Dodoma Region, Tanzania

This study was conducted in the Kongwa District to assess the fertility status of soils of the selected fields under maize production to understand fertility variability among soils and recommend appropriate fertilizer rates. The study involved randomly selected 24 maize fields. Composite soil samples were collected in these fields at 0–20 cm deep and characterized for soil fertility status. Results indicated that 48% of the soils were sandy clay loam and 26% were sandy loam. The remaining fields had clay or loamy sand textural classes. The soil pH ranged from extremely acidic (3.52) to moderately alkaline (7.7), organic carbon ranged from very low to medium (0.19-1.60%) and total N were very low to low (0.01-0.15%). Also, results indicated that 42% of soils had P deficiency and 16.7% had inadequate S levels. In addition, 45.8% of the soils had inadequate exchangeable K and exchangeable Mg levels ranged from very low to high (0.29-4.06 cmol(+) kg-1). Exchangeable Ca was low to very high (1.06 to 10.04 cmol(+) kg-1) with favourable base saturation for crop production. The CEC ranged from very low (2.62 cmol(+) kg-1) to medium (18.9 cmol(+) kg-1). Extractable micronutrients such as Cu, Fe, and Mn were adequate but Zn was inadequate in 58% of the soils. Categorizing nutrient status in soils of the study area showed that fertility is poor regarding N, P, K, Zn, Mg, and Ca. Hence, the studied soils need external nutrient inputs and proper management to optimize crop production.

PENGGUNAAN MULSA PLASTIK SEBAGAI UPAYA KONSERVASI LAHAN UNTUK MENJAGA STABILITAS SIFAT FISIKA DAN KIMIA TANAH

Low nutrient availability and high soil bulk density are caused by the loss of fertile soil particles due to the kinetic energy of rain. Land management that does not apply conservation principles such as soil covering is one of the factors causing this to happen. This research was conducted to determine the impact of using plastic mulch as one of conservation actions. This research was conducted at the experimental field University of Siliwangi, Mugarsari. Soil samples were taken from mulched and without mulch lands as treatments. Soil samples were collected at 0-10 and 10-30 cm soil depths. Soil samples were taken to analyze the chemical properties of the soils (i.e., pH H2O, organic C, total N, available P, exchangeable K, Ca, Mg, Na) and physical properties (i.e., soil bulk density, porosity, water content, and texture). The results showed that the use of mulch had a significant effect (p<0.05) on pH H2O, organic C, total N, available P, exchangeable K, exchangeable Ca, bulk density, and water content. The results of the correlation showed that increasing organic C in mulched land had an effect on decreasing BD (r = -0.739). In addition, the organic C increased soil porosity (r = 0.612). Meanwhile, soil depth had no effect (p>0.05) on soil chemical and physical properties.

ANALISIS BEBERAPA SIFAT KIMIA TANAH PADA DUA MACAM PENGGUNAAN LAHAN DI SUNGAI KAKAP, KABUPATEN KUBU RAYA, KALIMANTAN BARAT

Paddy fields and mixed farming apply intensive agricultural cultivation, and sustainable land use causes changes in land quality, one of which affects soil chemical properties. This study aimed to compare soil chemical properties based on differences in the use of paddy fields and mixed farming in Sungai Kakap District, Kubu Raya Regency, West Kalimantan. Research in the field in Pal IX Village, Sungai Kakap Sub-district, Kubu Raya Regency, for sampling soil samples at 0-20 cm depth. Soil analysis was conducted at the Chemistry and Soil Fertility Laboratory, Faculty of Agriculture, Tanjungpura University. The results showed that the two fields, paddy fields, and mixed farming, had almost the same chemical properties in paddy fields pH, organic C, available P, cation exchange capacity (CEC), exchangeable Ca and exchangeable Mg.

Durum Wheat Production and Soil Chemical Properties in Response to Three Biannual Rotation Cycles with Residue Incorporation

Crop rotations incorporating residues generates benefits in productivity and a better efficiency of resources. However, the incorporation of residues in high quantities is not a common practice, given the lack of comprehension of farmers of the effects on the following crop. This experiment was carried out in an Andisol soil in south-central of Chile. Three biannual rotation cycles (canola-durum wheat and bean-durum wheat) with four levels of residue incorporation (0%, 50%, 100% and 200%) were evaluated on the evolution of grain yield and production of durum wheat residues, and on chemical properties of the soil at the end of the three cycles. The results indicated that pre-cultivation affected the grain yield and residue production of durum wheat, highlighting the positive effect of the bean. In soil, a higher concentration of available N and exchangeable Ca, Mg and K was obtained in the bean-durum wheat rotation, and a higher concentration of available S in the canola- durum wheat rotation. By increasing the dose of waste, an increase in the concentrations of exchangeable Ca, Mg and K was achieved. Finally, the chemical properties of the soil presented positive and negative correlations associated with the management of liming, fertilization and nutrients mostly present in the incorporated waste. This study helped to validate that the continuous incorporation of the residues produced within the rotations in this volcanic soil contributes to the improvement of some of its chemical properties with no effect of yield of the durum wheat crop.

Properties of soils on fluvio-marin landform and their land management strategy for paddy field in Bataguh swampy area, Kapuas Regency, Central Kalimantan Province, Indonesia

Tidal swamp land has strategic and prospective value in sustaining national food resiliency and reserves. This land has the potential for the development of commodity paddy fields. However, this type of tidal swamp has a unique character and influences land management. This research aims to determine soil properties on landform fluvio-marine and its potential for developing lowland rice in Bataguh District, Kapuas Regency, Central Kalimantan. A total of 4 representative soil profiles were identified and characterized in the field and laboratory. Research results show that the lands under study have fine texture. Soils in the surface layer are classified as very acidic to acidic (soil pH 3.3-4.7), has very high organic C levels (5.46-9.37%), potential P moderate (21-40 mg.100g-1), K potential low until moderate (16-21 mg.100g-1), exchangeable Ca low (2.24-3.17 cmolckg-1), exchangeable Mg medium (5.11-8.30 cmolckg-1), soil CEC medium until high (19.63-38.09 cmolckg-1), and base saturation low until high (37-63%). The depth of sulfidic materials or pyrite layer is shallow until deep within 50-85 cm. The sand mineral fraction is dominated by quartz, while the mineral fraction of clay is dominated by kaolinite, followed by vermiculite and illite. The land studied is classified as marginally suitable (S3) for the development of tidal rice fields with a limiting factor for acid to very acid soil reactions (soil pH <5). Balanced fertilization, liming, and micro water management can be done to increase the productivity of this land.

Quality of Soils in Soybean Producing Areas in Caraga Region

This study aims to determine the soil quality of selected soybean producing farms in the Caraga region using soil quality index (SQI) measurements. Five sites were selected in the municipalities of San Miguel, Surigao del Sur and Trento, Agusan del Sur. Three 10×10 m soil monitoring plots were established within soybean fields in each site. Within each monitoring plot, three composite samples were collected coming from 10 subsamples using a soil probe. SQI was calculated following three general steps, (1) selection of minimum dataset (MDS) via Principal Components Analysis (PCA), (2) Scoring of MDS via linear method, and (3) Calculation of weighted overall SQI. Out of the 16-soil property indicator, a total of five soil properties (exchangeable Ca, % Sand, Electrical conductivity, available P, and Soil respiration) were extracted and used as the MDS for the calculation of SQI in each site. The main indicator properties for determining the quality of the soils in the area were Exchangeable Ca and % Sand contents offering a 68% and 26% weights over other soil properties, respectively. High SQI classification was found on four out of five sites evaluated, these were the two sites in the Municipality of Trento (Cebolin.M (61%) & Cebolin.T (54%)) and two sites in the Municipality of San Miguel (Libag-Gua (68%) & Upper Carromata (93%)). One site in San Miguel revealed a low SQI (Lower Carromata (41%)). These SQI values indicate that in these areas, soils with very high Exchangeable Ca and Sand content could have a low-quality condition, and sites with optimal Exchangeable Ca (400 - 600 ppm) contents and loamy to sandy loam texture could be classified as high quality soils. Proper drainage system could be best done to manage the very high exchangeable Ca content in these soil and thus, could improve its quality.

Can the Firmness, Weight, and Size of Blueberry Fruit Be Enhanced through the Application of Low Amounts of Calcium to the Soil?

The firmness, weight, and size of blueberries are vital for commercial success of this crop. Fertilization is a key agronomic management practice that affects fruit quality, where calcium (Ca) plays a critical role. This study aimed to assess the impact of low levels of soil-dosed Ca in carboxylic acid form on fruit size, weight, firmness, and residual soil fertility. The study focused on two varieties of blueberries, Duke and Legacy, over two consecutive growing seasons on three commercial farms located in south-central Chile. This study consisted of five treatments, ranging from 0 to 4.0 kg Ca per hectare. The highest firmness values observed for Duke were between 164 and 186 g mm-1, with size values ranging from 15.7 to 16.9 mm, and weight observations ranging from 1.60 to 1.76 g. On the other hand, Legacy showed firmness values between 163 and 173 g mm-1, with size values ranging from 16.2 to 17.2 mm, and weight observations ranging from 2.01 to 2.40 g. The application of low Ca rates to the soil did not impact the size, weight, or firmness of 'Duke' and 'Legacy' blueberries. There was a positive correlation between the Ca soil application and the concentration of exchangeable Ca.

Profile Distribution of Available Boron and Secondary Micro Nutrients in Rice-Groundnut Growing Soils of Jajpur District, Odisha, India

An investigation was conducted to examine the distribution of available Boron secondary micro nutrients and the relationships between boron with soil properties and other nutrients in the rice-groundnut growing soils of Jajpur district, Odisha. The clay content increased downward without following any definite trend. Soil pH of surface horizons was acidic and increased downward to neutral range. EC ranged between 0.02 dSm-1 to 0.13 dSm-1. The soil organic carbon ranged from 0.17% to 0.63% with decreasing trend towards sub surface horizon. The exchangeable Ca, Mg and S content varied from 3.68 mg kg-1 to 6.76 mg kg-1, 0.82 cmole (p+) kg‑1 to 6.24 cmole (p+) kg-1 and 0.62 mg kg-1 to 14.19 mg kg-1 respectively. Ca and Mg increased with increasing depth, whereas S showed the reverse trend. The DTPA- Fe, Mn, Cu, Zn and B content of pedon soil ranged from 60.68 mg kg-1 to 312.08 mg kg-1, 6.48 mg kg-1 to 36.76 mg kg-1, 0.62 mg kg-1 to 4.15 mg kg-1, 0.42 mg kg-1 to 1.15 mg kg-1 and 0.05 mg kg-1 to 1.01 mg kg-1 respectively Fe, Mn and Zn increased from surface to sub surface but Cu and B showed the reverse trend. The availability of Boron is positively correlated with organic carbon, Exch. Mg, Fe, and Cu. Negatively correlated with pH, Exch. Ca, S, Mn, and Zn. Pedon soils were deficient with B, S, Zn and rich in Ca, Mg, Fe, Mn and Cu. Fe was in toxic level in table land zone of sukinda. The available B was found to be deficient throughout the district in up and medium land except in subsurface layers of low land. The availability of B is positively correlated with organic carbon, Exch. Mg, Fe and Cu factors but negatively correlated with pH, Exch. Ca, S, Mn, and Zn. In an agricultural district like Jajpur the key element B for rice-groundnut crop sequence should be applied to soil and leaf of rice, groundnut, and other crops grown in the district.