Soil Physical-chemical Properties Research Articles

Plant Growth-Promoting Bacteria Influence Microbial Community Composition and Metabolic Function to Enhance the Efficiency of Hybrid pennisetum Remediation in Cadmium-Contaminated Soil.

The green and efficient remediation of soil cadmium (Cd) is an urgent task, and plant-microbial joint remediation has become a research hotspot due to its advantages. High-throughput sequencing and metabolomics have technical advantages in analyzing the microbiological mechanism of plant growth-promoting bacteria in improving phytoremediation of soil heavy metal pollution. In this experiment, a pot trial was conducted to investigate the effects of inoculating the plant growth-promoting bacterium Enterobacter sp. VY on the growth and Cd remediation efficiency of the energy plant Hybrid pennisetum. The test strain VY-1 was analyzed using high-throughput sequencing and metabolomics to assess its effects on microbial community composition and metabolic function. The results demonstrated that Enterobacter sp. VY-1 effectively mitigated Cd stress on Hybrid pennisetum, resulting in increased plant biomass, Cd accumulation, and translocation factor, thereby enhancing phytoremediation efficiency. Analysis of soil physical-chemical properties revealed that strain VY-1 could increase soil total nitrogen, total phosphorus, available phosphorus, and available potassium content. Principal coordinate analysis (PCoA) indicated that strain VY-1 significantly influenced bacterial community composition, with Proteobacteria, Firmicutes, Chloroflexi, among others, being the main differential taxa. Redundancy analysis (RDA) revealed that available phosphorus, available potassium, and pH were the primary factors affecting bacterial communities. Partial Least Squares Discriminant Analysis (PLS-DA) demonstrated that strain VY-1 modulated the metabolite profile of Hybrid pennisetum rhizosphere soil, with 27 differential metabolites showing significant differences, including 19 up-regulated and eight down-regulated expressions. These differentially expressed metabolites were primarily involved in metabolism and environmental information processing, encompassing pathways such as glutamine and glutamate metabolism, α-linolenic acid metabolism, pyrimidine metabolism, and purine metabolism. This study utilized 16S rRNA high-throughput sequencing and metabolomics technology to investigate the impact of the plant growth-promoting bacterium Enterobacter sp. VY-1 on the growth and Cd enrichment of Hybrid pennisetum, providing insights into the regulatory role of plant growth-promoting bacteria in microbial community structure and metabolic function, thereby improving the microbiological mechanisms of phytoremediation.

Comparative Assessment of Inorganic Fertilizer and Farm Yard Manure Application on Yield, Sustainable Yield Index and Soil Physico-Chemical Properties in Cauliflower-Capsicum Cropping Sequence in Northern- Western Himalayas

ABSTRACT Continuous addition of inorganic fertilizer and farm yard manure (FYM) alone or in combination is necessary to assess the changes in yield and soil properties. Therefore, a study was conducted for consecutive two years on nutrient management with nine treatments viz. T1- control, T2-100% FYM (N equivalent basis), T3-100% N, T4-NP, T5-NK, T6-PK, T7-NPK, T8-100% NPK+ FYM (recommended Practice) and T9- 150% NPK+ FYM to assess the influence of different treatments on yield, sustainable yield index, soil physic-chemical properties and soil carbon stock and sequestration rate in cauliflower and capsicum cropping sequence. Results showed that the addition of farm yard manure alone or in a combination with chemical fertilizers contributed to higher soil organic stock and soil carbon sequestration rate. Application of 150% NPK + FYM improved the SYI of system by 49.4% over a control. This treatment increases soil carbon stock by 12.5% from 25.9 Mg ha−1 to 29.6 Mg ha−1 and recorded with maximum soil carbon sequestration rate, i.e. 2.21 Mg C m−3 year−1 over the 2 years. Thus, balanced fertilization of NPK and FYM is beneficial for the maintenance of soil physical health, improving CEC and macro and micronutrient levels.

Carbon Sequestration in Sugarcane Plant-soil System as Influenced by Nutrient Integration Practices under Indo-Gangetic Plains of India

Sugarcane is a multi-purpose crop. The capability of sugarcane crop to sequestrate carbon into soil and plant is of great importance. Under this study the carbon sequestration in planted sugarcane and their rhizospheric soil under different nutrient management practices was assessed. As IPCC reported, that the rising temperature of earth surface resulted of GHGs emission which causes global warming. In order to stabilize the global temperature, the anthropogenic CO2 has to be mitigated to a significant level and the surplus atmospheric CO2 in plants and soil has to be sunk, under this circumstance, sugarcane cultivation plays pivotal role in utilising CO2 since it is a C4 plant having high efficiency of utilising CO2 during photosynthesis. There is another intervention might be enhancing the CO2 capture by changing the nutrient management practices which enhances chlorophyll synthesis by the way of increasing nitrogen efficiency in sugarcane. The different treatment composition enhances photosynthesis where more CO2 has been captured. Thus the sugarcane crop and rhizospheric soils act as important carbon sinks in decarbonisation of atmosphere that ultimately reduces carbon level and causes the global cooling. Soil Properties and Carbon Storage: The results showed that soil physical properties and chemical properties were significantly differed among treatments due to application of different organic amendments over control. Soil organic carbon (SOC) was analysed which ranges from 0.47 to 0.67%. The different organic amendments treatments had a considerable effect on soil bulk density and porosity with significant improvement in soil carbon storage. Plant Carbon Storage: The carbon stocks in different sugarcane plant parts, including roots, shoots and leaves were significantly different. The highest amount of carbon stock was found in leaves (877.08 kg ha-1) under T6 followed by roots (668.74 kg ha-1) in T2 and carbon stock in shoots (422.77 kg ha-1) in T5 showing that 30.41% and 107.58% more carbons were stored in the leaves as compared to the roots and shoots while in roots 58.18% more carbon stored in comparison to shoots. The total carbon storage in sugarcane biomass including aboveground parts and belowground part i.e. roots, in different treatment was significantly different. The mean value of carbon stored in the aboveground parts (leaves and stalks) was significantly higher (1239.65 kg ha-1) than that of underground plant part (621.73 kg ha-1) (roots). The results showed that the sugarcane farming practices have promising effect for carbon sequestration and consequently enhancing the mitigation of climate change impacts.

Dredging wastewater discharge from shrimp ponds affects mangrove soil physical-chemical properties and enzyme activities

Dredging wastewater discharge is a significant environmental concern for mariculture near mangrove ecosystems. However, little attention has been paid to its effects on the soil physical-chemical properties and enzyme activities in mangrove habitats. This study compared the soil physical-chemical properties and enzyme activities in the polluted area that received dredging wastewater from a shrimp pond with those in the control area without wastewater to explore the effects of wastewater discharge on the soil physical-chemical properties and enzyme activities. Variations in soil physical-chemical properties and enzyme activities across different tidal flat areas and depths were also examined. The polluted area exhibited lower soil salinity (10.47 ± 0.58 vs. 15.64 ± 0.54) and moisture content (41.85 ± 1.03 % vs. 45.81 ± 1.06 %) than the control area. Wastewater discharge increased soil enzyme activities, (acid phosphatase, protease, and catalase), resulting in higher inorganic nitrogen (13.20 ± 0.00 μg g−1 vs. 11.60 ± 0.03 μg g−1) but lower total nitrogen (0.93 ± 0.01 mg g−1 vs. 1.62 ± 0.11 mg g−1) in the contaminated zone. From the control to polluted area, there was an approximate increase of 0.43 and 0.83 mg g−1 in soil total phosphorus and soluble phosphate, driven by increased acid phosphatase. However, soil humus and organic matter decreased by 0.04 and 1.22 %, respectively, because of wastewater discharge. The impact of wastewater discharge on the soil physical-chemical properties and enzyme activities was most pronounced in the landward and surface soil layers (0–5 cm). The results showed that wastewater discharge altered soil physical-chemical properties and enzyme activities, accumulating soil bioavailable nutrients (inorganic nitrogen and soluble phosphate), but at the cost of reduced soil quality, especially organic matter, further adversely affecting the overall health of mangrove ecosystems. Prioritizing the management of wastewater discharged from mariculture adjacent to mangrove forests is crucial for mangrove conservation.

Warming affects leaf light use efficiency and functional traits in alpine plants: evidence from a 4-year in-situ field experiment.

Light use efficiency (LUE) is a crucial determinant of plant productivity, while leaf functional traits directly affect ecosystem functions. However, it remains unclear how climate warming affects LUE and leaf functional traits of dominant species in alpine meadows. We conducted a 4-year in-situ field warming experiment to investigate the eco-physiological characteristics for a dominant species (Elymus nutans) and a common species (Potentilla anserina) on the Tibetan Plateau. The leaf traits, photosynthesis and fluorescence characteristics were measured, along with the soil physical-chemical properties associated with the two species. Experimental warming increased the leaf LUE, maximum photochemical efficiency, non-photochemical quenching, relative water content and specific leaf area for both species. However, there was a decrease in leaf and soil element content. Different species exhibit varying adaptability to warming. Increasing temperature significantly increased the photosynthetic rate, stomatal conductance, transpiration rate, total water content, and specific leaf volume of E. nutans; however, all these traits exhibited an opposite trend in P. anserina. Warming has a direct negative impact on leaf LUE and an indirectly enhances LUE through its effects on leaf traits. The impact of warming on plant photosynthetic capacity is primarily mediated by soil nutrients and leaf traits. These results indicate that the two different species employ distinct adaptive strategies in response to climate change, which are related to their species-specific variations. Such changes can confer an adaptive advantage for plant to cope with environmental change and potentially lead to alterations to ecosystem structure and functioning.

Effects of water stress on nutrients and enzyme activity in rhizosphere soils of greenhouse grape.

In grape cultivation, incorrect water regulation will lead to significant water wastage, which in turn will change soil structure and disrupt soil nutrient cycling processes. This study aimed to investigate the effects of different water regulation treatments [by setting moderate water stress (W1), mild water stress (W2), and adequate water availability (CK)] on soil physical-chemical properties and enzyme activity in greenhouse grape during the growing season. The result showed that the W2 treatment had a negative impact on the build-up of dissolved organic carbon (DOC), nitrate nitrogen (NO3-N), and available phosphorus (AP). Throughout the reproductive period, the W1 and W2 treatments decreased the soil's microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) contents, and MBC was more vulnerable to water stress. During the growth period, the trends of urease, catalase, and sucrase activities in different soil depth were ranked as 10-20 cm > 0-10 cm > 20-40 cm. The urease activity in 0-10 cm soil was suppressed by both W1 and W2 treatments, while the invertase activity in various soil layers under W1 treatment differed substantially. The W1 treatment also reduced the catalase activity in the 20-40 cm soil layer in the grape growth season. These findings suggested that W2 treatment can conserve water and enhance microbial ecology of greenhouse grape soils. Therefore, W2 treatment was the most effective water regulation measure for local greenhouse grape cultivation.

Ecosystem function associated with soil organic carbon declines with tropical dry forest degradation

AbstractForest degradation is increasingly recognized as a major threat to global biodiversity and the multiple ecosystem services forests provide. This study examined the impacts of forest degradation on soil quality and function in a seasonally dry tropical forest (SDTF) of Ecuador. Previous studies of SDTFs have focused on the impacts of land‐use conversion on soils, while this study assessed the less visible but pervasive effects of degradation. We compared soil physical–chemical properties, enzymatic activity, particulate organic carbon (POC) and mineral‐associated organic carbon (MAOC) along a gradient of SDTF degradation in both the dry and rainy season. Our findings showed a consistent and steady reduction in soil quality (total C and N) and function (dehydrogenase and β‐glucosidase activity) that paralleled the loss of vegetative structure and diversity along the degradation gradient. Soil physical–chemical properties were less variable and enzymatic activity was generally higher in the dry season compared to the rainy season. We also showed for the first time a significant and uniform decrease in POC and MAOC with degradation in SDTF. The relative proportion of these two components was constant along the gradient except in the most degraded state (arid land), where POC was higher in proportion to MAOC, suggesting that extreme forest degradation may cause this ecosystem to cross a functional tipping point. These findings address an important knowledge gap for SDTFs by showing a consistent loss of soil quality and functionality with degradation, and suggest that extreme degradation can result in an alternate state with compromised resilience.

Chemodiversity of Dissolved Soil Organic Matter from Amazon Rainforest as Influenced by Deforestation.

Many biogeochemical processes are modulated by dissolved organic matter (DOM), but the drivers influencing the chemodiversity of DOM compounds in Amazonian soils are poorly understood. It has also been theorized whether deforestation controls the decline of DOM. In this study, we collected soil samples from thirty sites across different regions of Brazil's Legal Amazon, and we investigated the trade-offs among soil physical-chemical properties and DOM chemodiversity. We employed optical spectroscopy, Fourier transform ion cyclotron resonance, and multivariate analysis. Our results indicated that, despite variations in land use and soil physical-chemical properties, factors such as the deforested site, geometric mean diameter, weighted average diameter, and soil organic carbon were the main influencers of DOM chemodiversity variation. These findings highlight the importance of considering DOM chemodiversity as closely related to land use and its potential use in developing deforestation models for predicting soil quality decline in Brazil's Legal Amazon.

Influence of soil physicochemical properties on diversity and distribution of aquatic vegetation in the riverine forested habitats

Riverine flora is one of the most dynamic aspects of a landscape, and it involves species which are adapted and specialised to grow in a range of environmental conditions. An ecological analysis was conducted to describe the phyto-sociological and floristic structure of the plant species in the riverine forest at Balloki along moisture gradients caused by river bank. A random quadrat method with a quadrat size of 1 × 1 m was used for sampling of the riverine site. All plant species growing in the riverine habitats were collected and identified. A detailed survey was conducted to record the ecological attributes such as density, frequency, cover, and importance value. These values were then used to calculate the relative values of these ecological indicators. These ecological indicators were correlated with various soil physical parameters (soil texture, moisture contents and saturation percentage), chemical properties (ECe and pH), and nutrients (Na, Ca, K and N). Most of the species were linked to sites 3 and 4 with high moisture content, low ECe, acidic pH and moderate nutrient composition. The species with the highest ecological importance were Cynodon dactylon, Rumex dentatus and Saccharum spontaneum which accounted for more than 80% of the total abundance. It was concluded that species distribution differed significantly along the four study sites mainly depending on the soil-physicochemical features of the study sites.

Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray, Ethiopia

Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray, Ethiopia

A new quality index based on soil-vegetation networks to determine the recovery of functionality in abandoned agrosystems

The development of indices of ecosystem quality makes it possible to obtain robust information with less human and material effort. These indices are especially useful for assessing the quality of ecosystems disturbed by anthropogenic impact since they can inform management decisions designed to recover their functionality. The abandonment of agricultural activity is a major environmental challenge, and it is important to understand its consequences on ecosystem functioning. The main objective of this work was to develop a robust quality index of abandoned agrosystems based on detailed information on soil properties and structure and the composition of the vegetation. A chronosequence was built of abandoned vineyards over the last 60 years. Seventeen soil physical-chemical properties and ten enzymatic activities related to the cycles of C, N, P and S were determined in 21 plots along the chronosequence. Total vegetation cover, cover of cryptograms and phanerogams and cover of plant functional groups was also recorded. The main factors involved in the quality of the ecosystem were detected by means of network analyses based on these variables. Models were then developed to calculate ecosystem quality indices. Our results showed how the evolution of soil properties occurred simultaneously with variations in the composition and structure of the vegetation. The major factors that determined the functionality of abandoned agrosystems were the quantity and quality of soil organic matter (high TOC and WHN) and the lesser abundance of sulphur accumulator plants. The ecosystem quality index model found to be the most robust was the index with integration by weights and non-linear scores, which followed a sigmoid pattern throughout the chronosequence. Our results highlight the importance of developing robust quality indices based on an interdisciplinary approach.

Influences of conservation tillage on soil macrofaunal biodiversity and trophic structure in the Mollisol region of Northeast China

Tillage regimes directly impact soil disturbance and crop residue levels in the field, subsequently affecting soil macrofauna abundance and diversity, crucial for maintaining soil health and ecosystem functionality. The present study aimed to investigate the effects of different tillage regimes (no-tillage (NT), conventional tillage (CT) and reduced-tillage (RT)) on soil properties and macrofaunal communities in a typical black soil region of Northeast China. Our study revealed that, in comparison to CT and RT, NT significantly enhanced soil macrofauna biodiversity and brought about modification in the community composition. Additionally, it reduced changes in the soil physical–chemical properties. Furthermore, the choice of tillage regimes impacted the trophic structure of soil macrofauna, manifesting in great density and species richness of herbivores and predators in NT plots with crop residue retention when compared to those managed with tillage. Overall, soil organic carbon (SOC) and pH played pivotal roles in regulating the soil macrofaunal community. The alternations observed in the soil macrofaunal community represented a comprehensive response to tillage practices and residue return, which in turn influenced soil properties and microenvironments, including food resources and microhabitats. Therefore, our findings indicated that conservation tillage exerted a notable influence on the soil macrofaunal community. This underscores the significance of soil environments and properties in molding the structure and composition of the soil macrofaunal community. The study will enhance comprehension of soil management practices and advocate for diversity within soil macrofaunal communities.

Linkages of Enzymatic Activity and Stoichiometry with Soil Physical-Chemical Properties under Long-Term Manure Application to Saline-Sodic Soil on the Songnen Plain

Excess Na+ and high pH result in poor structures in Saline-Sodic soils, which reduces extracellular enzyme activity (EEA) and causes nutrient limitations. The application of manure improved the Physical-Chemical properties of soil and balanced the soil nutrient supply, which was reflected in the soil EEAs and stoichiometry. Five experimental treatments were designed according to the manure application duration as follows: manure application for 11 years (11a), 16 years (16a), 22 years (22a), and 27 years (27a) and a control treatment with no manure application (CK). The results of the redundancy analysis (RDA) showed that physical properties (mean weight diameter (MWD)) and EEA (β–glucosidase (BG)) significantly increased and bulk density (ρb) significantly decreased when the nutrient content increased. Additionally, soil pH, electrical conductivity (EC), exchangeable sodium percentage (ESP) and sodium adsorption ratio (SAR) significantly decreased after manure application. Based on stepwise multiple linear regression models (SMLR), total nitrogen (TN) was the dominant variable that significantly increased EEA, and the Mantel test showed that soil C:N significantly influenced enzyme stoichiometry. Furthermore, RDA showed that pH, soil C:N and TN were the main factors influencing EEAs and enzyme stoichiometry. Soil EEAs significantly increased with TN and decreased with pH and soil C:N, which affected enzyme stoichiometry. The enzyme stoichiometry increased from 1:2.1:1.2 and 1:2.7:1.5 to 1:1.7:1.2, and the vector angle (vector A) increased, which showed that the N limitation was relieved after the application of manure. The vector length (vector L) showed no significant difference in the C limitation at depths of 0–20 cm and significantly increased at depths of 20–40 cm. In conclusion, soil EEAs and stoichiometry improved with changes in TN and soil C:N, and pH decreased with changes in the soil structure after the application of manure, which accelerated the soil nutrient cycle and balanced the soil nutrient supply.

Thallium content in vegetables and derivation of threshold for safe food production in soil: A meta-analysis

Soil thallium (Tl) pollution is a serious environmental problem, and vegetables are the primary pathway for human exposure to Tl. Therefore, it is important to investigate the characteristics of soil Tl uptake by vegetables. In this study, the meta-analysis approach was first applied to explore the relationship between Tl content in vegetables and soil environment, as well as key factors influencing soil physical–chemical properties, and to derive soil thresholds for Tl. The results indicated that various types of vegetables have different capabilities for Tl accumulation. Vegetables from contaminated areas showed high Tl accumulation, and the geomean Tl content in different types of vegetables was in the following order: leafy > root–stalk > solanaceous vegetables. Taro and kale had significantly higher capability to accumulate soil Tl among the 35 species studied, with Tl bioconcentration factor values of 0.060 and 0.133, respectively. Pearson correlation analysis and meta-analysis revealed that the Tl content in vegetables was significantly correlated with soil pH and Tl content in soil. The linear predictive model for Tl accumulation in vegetables based on soil Tl content described the data well, and the fitting coefficient R2 increased with soil pH value. According to potential dietary toxicity, the derived soil Tl thresholds for all, leafy and root–stalk vegetables increased with an increase in soil pH, and were in the range of 1.46–6.72, 1.74–5.26 and 0.92–6.06 mg/kg, respectively. The soil Tl thresholds for kale, lettuce and carrot were in the range of 0.24–4.89, 2.94–3.32 and 3.77–14.43 mg/kg, respectively. Ingestion of kale, beet, sweet potato, potato, taro, pepper, turnip, Chinese cabbage, eggplant and carrot poses potential health risks. The study provides scientific guidance for vegetable production in Tl-contaminated areas and can help with the selection of vegetable species suitable for avoiding the absorption of Tl from contaminated soil.

Lithology‐mediated soil erodibility characteristics after vegetation restoration in the karst region of Southwest China

AbstractEcological restoration projects have significantly increased global vegetation cover and reduced soil erosion. However, it is very challenging to clarify the complex soil erosion mechanisms of limestone and dolomite in the southwest karst region and to identify the key factors affecting erosion. The study site has a subtropical monsoon climate with precipitation concentrated during the rainy season from May to September. In this study, four plantation restoration measures with a recovery time of approximately 16 years were selected, which included arbor forest, orchard, grassland, and cropland (control). Soil physical–chemical properties and soil erodibility K values were used to evaluate the soil erosion characteristics. The results showed that both limestone and dolomite exhibited lower soil bulk density as well as higher capillary porosity, and soil water‐stable aggregates after revegetation. The limestone and dolomite K values were reduced by 12%–15% and 15%–17%, respectively. However, the K value of limestone was 17.9% higher than that of dolomite, indicating that dolomite exhibited a higher stability. Through redundancy analysis and structural equation modeling, revegetation was found to reduce soil erosion by influencing the soil particle composition. The silt was the key factor influencing soil erosion, accounting for 84.4% and 78.2% of the variation in the limestone and dolomite K values, respectively. These findings suggest that vegetation restoration enhances soil erosion resistance; however, the effectiveness of restoration is controlled by the lithology in the southwest karst region. These findings provide a reference for soil and water management and vegetation restoration.

Evaluation of the Suitability of Alfisol of Derived Savanna for Rice Production in Southwestern Nigeria

The combination of quantitative and qualitative studies in land evaluation is important for decision making on the adoption of specific land utilization type. This study evaluates the suitability of two locations for rice production in an alfisol of derived savanna, Ikole-Ekiti, Southwestern Nigeria. Two locations; Ikole - Ijesa-Isu road (K1) and Ikole - Osin road (K2) were selected and a profile was dug in each of the site, described according to the standard and sampled for laboratory analysis of soil physic-chemical properties. Field experiment was conducted in 2022 cropping session to evaluate the performance of rice in the two locations. The locations were considered as the treatment and rice was planted in the representative portion of each of the site in four replicates. The experiment was a randomized completely block design. Recommended cultural practices for rice in the derived savannah zone of Nigeria were followed. Yield data were collected in tons per hectare and analyzed with T-test at 5% probability level. Results obtained revealed that the soils pH ranged from 5.5 to 6.2, organic carbon is from 0.4 to 5.01% and total nitrogen from 0.08 to 0.19%. K1 had actual index of suitability of 34.88 therefore rated marginally suitable while K2 was 19.37 for rice. The potential index of suitability of K1 was 80 highly suitable and K2 was 60 moderately suitable. Highest rice yield of 1.03 t ha-1 was obtained in K1. K1 was recommended as preferred location for rice cultivation in the study area. Suitability evaluation should be followed by qualitative experiment in order to make recommendations that are adoptable for farmers.

Nutrient status assessment and mapping of intensively managed paddy soils in southeastern hilly areas of Bangladesh

AbstractBackgroundPeople living in the southeastern hilly areas of Bangladesh are primarily dependent on agriculture and face the problem of nutrient deficiency in soils. This research was conducted to assess the fertility status of paddy soils for better fertilizer management. Grid sampling (1 km × 1 km) was followed to collect soil samples, avoiding unusual spots (e.g., non‐agricultural land, settlements, hills, and forests). In total, 300 samples were collected (150 from each upazila) to assess the status of soil physical properties (soil texture) and chemical properties (pH, electrical conductivity, organic matter, and nutrients [nitrogen (N), phosphorus (P), potassium (K), sulfur (S), magnesium (Mg), boron (B), and zinc (Zn)]).ResultsResults revealed that most of the soils were sandy to silt loam in texture. The soils were found to be strongly acidic with values of 4.79 and 4.73 in Ukhiya and Teknaf, respectively. Most of the soils were found to be nonsaline, except the paddy soils close to the sea and/or salt‐affected cultivated land. Soil organic matter in Ukhiya and Teknaf was low (1.47% and 1.43%, respectively). The soils in both upazilas were deficient in N, P, K, S, and Zn, but not in Mg in both upazilas and B in Teknaf.ConclusionIt is imperative that adequate amounts of nutrient provision are available to maintain soil health and produce a sustainable crop yield. We believe that these are the first digital soil maps developed at upazila level using ArcGIS software, which will be available for future reference.

Domestic sewage wastewater irrigation in the semi‐urban ecosystem on soil physical–chemical properties and environmental food security perspectives of two vegetables

AbstractNowadays, using domestic sewage wastewater for agricultural irrigation is becoming increasingly important for sustainable water resources management. Several national and international programs have been implemented to mitigate wastewater. However, it is important to ensure that these measures are affordable, effective, and sustainable. The aim of the present study is to determine, after all these mitigations, whether these domestic sewage wastewaters can be used as a potential irrigation source and at the same time ensure environmental food security. With these objectives, we analyzed the consequences of domestic sewage effluent irrigation on soil physical–chemical properties and nutritive and nutraceutical properties of cultivated green vegetables, Luffa acutangula (L.) Roxb. and Lagenaria siceraria (Molina) Standl., in the semi‐urban ecosystem compared with well water irrigated crops in a rural area. The quality status of both well water irrigated and domestic sewage wastewater irrigated soil samples showed similar and/or comparable values, that is, domestic sewage wastewater irrigation does not harm the soil quality and both were comparable with the permissible limits of BIS (Bureau of Indian Standards) including heavy metal contents. And positively supporting the objective of our study, the nutrient status/proximate composition of both the vegetables in terms of protein, gross energy, carbohydrate, etc., were higher in domestic sewage wastewater irrigated crops compared with the well water irrigated crops. The antioxidant activity also exhibited a significant increase in the sewage wastewater irrigated crops rather than the well water irrigated ones. Hence the results of the present study state that due to the impact of the mitigation measures, domestic sewage wastewater is now pertinent to be used as an irrigation source and also a possible organic fertilizer without any ambiguity. Moreover, more field‐oriented studies may ensure the potential of wastewater irrigation for sustainable crop production without any pollution, particularly in a semi‐urban area.

Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau, China

Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau, China

Effect of Morphological Characteristics of Fruit Orchards on Soil Physio-chemical Properties

Biophysical characteristics of 16-year-old fruit orchards and their influence on soil physico-chemical properties of sixteen-year-old fruit orchards established at Krishi Vigyan Kendra, Birouli, Samastipur (Bihar) were compared. Fruit orchards were Mango (Mangifera indica) var. Malda, Litchi (litchi chinensis) var. China and Aonla (Emblica officinalis) var. NA-7. An investigation was undertaken to evaluate the dynamics of Oxidisable Organic Carbon (Coc), SOC sequestration, Bulk Density (BD), pH and Electrical Conductivity (EC) in fruit orchards. All the orchards significantly improved SOC showing 12.9 to 44.6 % higher than that in open (without trees) and followed the order: Aonla > Litchi > Mango. The total SOC increased by 10 to 20 % at the surface and 15 to 35 % in the lower depths. The crown diameter of Mango, Litchi and Aonla orchards were 11.64 m, 8.61 m and 8.6 m and girth at breast height (GBH) varied from 9.53 m in Aonla orchard to 5.6 m in Litchi orchard. By and large, Aonla orchard may be considered as the best orchard production system from the standpoint of SOC build up and improvement in soil physic-chemical properties. Hence, its promotion and expansion as land-use practices in the calcareous belt of Bihar will be helpful for food security and mitigating climate change.