Determine Soil Chemical Properties Research Articles

Soil Chemical Properties and Nutrient Status on Various Land Slopes of Gayo Arabica Coffee Plantation, Aceh Indonesia

The chemical and nutrient properties of soil on various land slopes are related to the management of integrated and sustainable coffee plantation. The aim of the study was to determine soil chemical properties and nutrient availability on various slopes of Gayo Arabica coffee plantations. A total of 12 composite soils for laboratory analysis were taken from Arabia coffee plantation owned by the community in Bandar District, Bener Meriah Regency. The selection of the research location was determined by purposive sampling. The independent variable was slope of the land, while dependent variables were soil chemical properties and available nutrients. The results showed that the soil chemical properties which were significantly different on various land slopes were C-organic, CN ratio, and base saturation. C-organic content and C:N ratio decreased with increasing slope of the Gayo Arabica coffee plantation. On the contrary, base saturation as the slope of the Gayo Arabica coffee fields rises.

Changes in rhizosphere-specific enzyme activity during secondary grassland succession in the Loess Plateau, China

ABSTRACT Dynamics of soil enzyme activity during plant restoration processes have been studied extensively; however, a general understanding of the rhizosphere-specific enzyme activity during plant secondary succession is limited. Rhizosphere samples were collected from the dominant and main companion species in farmlands abandoned for up to 32 years in the Loess Plateau. We determined soil chemical properties, phospholipid fatty acid (PLFA) profiles and activities of four enzymes (β-1,4-glucosidase, BG; β-1,4-N-acetylglucosaminidase, NAG; L-leucine aminopeptidase, LAP and alkaline phosphatase, AP), specific enzyme activity per soil organic carbon (SOC) and per PLFA unit. Specific BG, NAG, LAP and AP activities per SOC unit significantly decreased 77.1%, 53.2%, 83.0% and 49.2% with plant succession. Specific BG, NAG and LAP activities per PLFA unit significantly decreased 59.6%, 18.9% and 70.9% with plant succession. Furthermore, specific BG and LAP activities in the dominant species were lower than those in the companion species. Redundancy analysis revealed that variations in specific enzyme activities per SOC and per PLFA unit were explained 76.6% and 68.6% by soil chemical properties. SOC, total nitrogen (TN) and available phosphorus (aP) significantly influenced the rhizosphere-specific enzyme activities. This study improved the understanding of the element cycle at the root–soil interface under secondary succession ecosystems.

Understanding variations in soil properties and microbial communities in bamboo plantation soils along a chromium pollution gradient

With high biomass productivity and resistance to heavy metals (HM) stress, bamboo has strong potential for HM phytoremediation. However, few studies have been conducted under field conditions to explore changes in soil physicochemical and microbial properties of bamboo forests with HM-contaminated soils. This study established bamboo (Phyllostachys praecox) plantations in five Cr-contaminated sites with different pollution levels (low, L; low-moderate, LM; moderate, M; moderate-high, MH; and high, H). We determined soil chemical properties, total and available Cr content, as well as bacterial and fungal community structures from 0 to 20 cm depth along the pollution gradient, and evaluated their interactions. The results revealed a corresponding decrease in soil pH, alkali-hydrolysable N (AN), along with urease and sucrase activities, as Cr pollution increased. In contrast, total organic carbon (TOC) increased with increasing Cr pollution. Soil available P (AP) and acid phosphatase activity did not differ significantly. Different pollution level resulted in distinct bacterial and fungal communities, with Proteobacteria, Acidobacteria, Actinobacteria, Ascomycota, and Basidiomycota being the dominant phyla across the five bamboo soils. Both total Cr (TCr) and HCl-extractable Cr (ACr) negatively correlated with alpha indices (Chao1 and Shannon) for bacteria but not for fungi, indicating that the latter is more resistant to Cr pollution. Decrease in soil pH and increase in TCr and ACr from L to H were closely related to the shift of bacterial and fungal communities. These changes reduced soil N and C cycles. Our findings suggest that improving soil acidic conditions and N availability enhances carbon and nitrogen cycles via altering soil microbial structure and activities. This, in turn, can increase phytoremediation efficiency in the bamboo ecosystem.

Changes in soil quality under conservation agriculture practices in West Nusa Tenggara, Indonesia

The main challenge for cultivating upland in semi arid environment as in West Nusa Tenggara, Indonesia is the limited availability of water resources and accelerated deterioration of soil quality. This study evaluated changes in selected soil properties and soil quality 4 years after the implementation of conservation agriculture (CA) practices. The study was conducted at the CA demonstation plots in Gunung Malang Village, Pringgabaya District, East Lombok Regency, West Nusa Tenggara Province. The surface soil texture was loam with slope ranging from 5 to 10%. Two CA Models and one farmer practice (LP) were compared. Within each model three sampling positions were sampled: within the corn planted area (Position A), 0-10 cm from the edge of the corn planted area (Position B), and 10 – 20 cm from the edge of the corn planted area (Position C). Intact soil samples (76 by 40 mm) were taken from the three positions at two depths (100-mm increments) to determine soil physical properties and bulk samples from the surface soil (0 – 15 cm) to determine soil chemical properties in the laboratory. The CA Model had significantly (<em>P</em> < 0.01) lower bulk density (BD), and increase soil organic carbon (SOC) and available P (Av P), while Position had significantly affect only BD. The lowest BD (0.87 ± 0.07 Mg m-<sup>3</sup>) and the highest SOC (1.51± 0.05%) and available pore water (AWC; 18.06 ± 0.76% vol) were found at Position A in CA with permanent pit (PIT). The highest soil quality index was found in Position A followed by Position B and the least was in C indicating that the crop rotation component in CA had relatively small effect on improving soil quality. These results suggested that there is a gradual improvement on soil quality after 4 years of the implementation of conservation agriculture and require longer time than 4 yr to achieve the best soil quality for this semi arid environment

Integrated production systems: An alternative to soil chemical quality restoration in the Cerrado-Amazon ecotone

Soil organic carbon (SOC) is the main terrestrial carbon reservoir. The spatial distribution of SOC is mainly regulated by environmental factors and anthropogenic activity. Historically, land-use change has been responsible for much of the world’s greenhouse gas emissions. However, carbon storage can be improved through agricultural management, either by increasing carbon inputs through higher crop yields or by delaying the release of carbon into the atmosphere. Therefore, it is essential to correctly choose which cover crops to use and how long these crops will remain in the crop rotation system. In order to clarify these issues, the objective of this work was to evaluate the chemical quality and changes in soil carbon stock between no-tillage and soybean/corn crop succession systems and integrated crop-livestock systems. The study was carried out in Querência (MT), Brazil, located in the Cerrado/Amazon ecotone. The integrated systems were studied between 2007 and 2014. These systems followed annual crop rotation and forage rotation, and were laid out as a consortium or were isolated, with the aim of producing grain and meat. In order to determine soil chemical properties, 170 sampling plots were randomized among the treatments. The highest carbon values were observed in the integrated crop-livestock systems (ICL), probably due to higher inputs of organic residues. Crop rotation with plants of different families allowed better land use and soil exploration. However, integrated production systems comprising longer pasture periods, no-tillage, and soybean/corn crop succession decreased soil carbon. When comparing carbon stocks from 2010 to 2014, only integrated production systems ICL2 and ICL3 were able to increase carbon stocks. Our results highlight the importance of length of growing and correct choice of cover crops in maintaining SOC stocks, and thus provide insights to improve SOC stocks in agricultural land in Brazil's main producing region.

Chemical Properties of Compost in Relation to Calcareous Soil ‎Properties and Its Productivity of Wheat ‎

Two field experiments were conducted during the two successive growing winter ‎seasons in a private farm at Abu El-Matamir, El-Beheira Governorate Egypt, on ‎wheat plant, to study the effect of three types of composts prepared from three ‎plant residues, i.e., maize (CMR), tomato (CTR) and vine (CVR) on chemical ‎properties of sandy calcareous soil (i.e., pH, EC, OM, CEC, CaCO3 and available ‎of some macro- and micronutrients) and its productivity of wheat yield and its ‎components. These composts were analyzed for their chemical composition and ‎content of available macro- and micronutrient. Each compost was added at rates ‎of 0, 5, 10 and 20 ton fed-1. ‎The prepared composts had wide variations in their chemical composition. For ‎example, CTR had a highest content of organic matter, total nitrogen and ‎available macro- and micronutrients, while the lowest values were found in ‎CMR. Soil pH, EC and CaCO3 were decreased as a result of compost ‎applications, while soil CEC, OM and available macro- (N, P, K, S, Ca and Mg) ‎and micronutrients (Fe, Mn, Zn and Cu) were increased. The high relative ‎changes of the determined soil chemical properties and its content of available ‎nutrients were found in the soil treated with CTR followed by those resulted from ‎CVR treatments. Increasing application rates of the used composts were ‎associated with an increase of both straw and grain yields of wheat and their ‎relative changes (%), where the highest yield was found with the treatment of ‎CTR followed by that of CVR. Also, CTR gave the highest value of agronomical ‎efficiency of wheat plants compared with the other two composts. Finally, the ‎application of CTR (20 ton fed.-1) was superior in greatly improving soil chemical ‎properties of the studied soil and reflected on wheat productivity and nutrients ‎uptake. ‎

Soil respiration, glomalin content, and enzymatic activity response to straw application in a wheat-maize rotation system

Straw residue has been widely applied in the North China Plain agroecosystems due to their positive roles in soil fertility improvement, sustainable production, and climate change mitigation. However, little is known about how straw application alters soil respiration by influencing soil biochemical properties in this region. This is the first study to evaluate the role of soil enzyme activity and glomalin content in the response of soil respiration to straw application at different growth stages in a wheat-maize rotation system. Field experiment was conducted in a wheat-maize rotation system and it contained two treatments: straw residue removal (CK) and straw residues application (SR). Soil respiration, moisture, and temperature were measured using LI-8100 at different growth stages during wheat and maize (2013–2015) growing seasons. From 2013 to 2014, soil sample (0–20 cm) was collected at different growth stages during wheat and maize growing seasons and transported to the laboratory. Glomalin content and soil enzyme activity were analyzed by using Bradford and enzyme-labeled meter method, respectively. In addition, we determined soil chemical properties such as soil organic carbon (SOC), soil total N content (TN), ammonium N (NH4 +-N), and nitrate N (NO3 −-N) concentrations. SR significantly increased soil respiration and this promotion effect became more significant after 4-year straw application. Soil respiration exhibited significant seasonal variation and was significantly increased by soil temperature with Q 10 ranging from 1.73 to 2.14 for CK and from 1.51 to 2.28 for SR. Both soil temperature and moisture accounted for 70–72% of the seasonal variation in soil respiration. SR significantly increased easily extractable glomalin-related soil protein during 2013–2014 wheat growing season except jointing stage. In addition, positive and significant effect of SR on activities of β-glucosidase and cellobiohydrolase was observed at initial and vigorous growth stages. Straw application significantly increased TN, but did not significantly influence SOC, NH4 +-N, and NO3 −-N concentrations. Our study demonstrated that straw application increased soil respiration by stimulating soil enzyme activities and improving easily extractable glomalin-related soil protein. Straw application is recommended as an agricultural management in the North China Plain because of its role in improving biochemical properties. To improve soil biochemical parameters with a relative low soil respiration rate, further information is necessary about the optimum amount of straw application.

Soil chemical properties as influenced by long-term glyphosate-resistant corn and soybean production in the central Great Plains, USA

Glyphosate-resistant (GR) corn (Zea mays L) and soybean (Glycine max (L.) Merr.) production and glyphosate application could affect soil chemistry due to indirect effects on soil organic matter (SOM) and nutrient cycling. We determined soil chemical properties after 15-yr of glyphosate application, continuous GR corn (CC) and GR corn-soybean rotation (CS) under no-tillage. Herbicide treatments were 1) glyphosate at 0.42 and 2) 0.84kga.e.ha−1 each applied twice in all years, 3) an alternating treatment of glyphosate at 0.84kgha−1 applied twice followed the next year by a non-glyphosate herbicide treatment, and 4) a non-glyphosate herbicide treatment in all years. Results showed that crop rotation and soil sampling depth affected SOM, pH, and nutrient concentrations. Soil pH, exchangeable Ca and K concentrations at the soil surface were reduced with CC production. In contrast, SOM, Fe, Mn, NO3-N, SO4-S and soil P concentrations in the top 7.5cm of the soil increased with CC production. Glyphosate application affected concentrations of P, NO3-N, SO4-S and Fe but not pH, Ca, Mg, Mn or Zn. Findings of this long-term study showed that crop management practices including herbicide program and crop rotation could affect soil chemical properties but cropping systems with CC increased soil surface fertility compared to CS production.

Temperature effects on soil organic carbon, soil labile organic carbon fractions, and soil enzyme activities under long-term fertilization regimes

The effects of temperature changes on soil organic carbon (SOC), labile organic carbon fractions (microbial biomass carbon, MBC; dissolved organic carbon, DOC; particulate organic carbon, POC), and enzyme activities under long-term fertilization regimes as well as their relationships at different temperatures were investigated in this study. Soil samples were collected in the fluvo-aquic soil of a 26-year fertilizer trial in the North China Plain after maize harvest in 2012, and four treatments were selected: control of no fertilizer (CK), standard rate of mineral fertilizer treatment (SMF), standard rate of organic manure treatment with N input rate equal to SMF (SMA), and half-standard rate of organic manure plus half-standard rate of mineral fertilizer treatment (1/2(SMA+SMF)). We determined soil chemical properties and labile organic carbon fractions using standard methods and the activities of nine soil enzymes involved in C, N, and P cycling in a 21-day incubation experiment at different temperatures (5°C, 15°C, 25°C, and 35°C) by micro-plate fluorometric assay. Additionally, we investigated the relationships among them using redundancy analyses (RDA) at four temperatures. The results indicated that (1) temperature, fertilization, and their interaction had significant effects on SOC, MBC, DOC, POC, and most of the soil enzyme activities; (2) long-term organic manure treatments (SMA and 1/2(SMA+SMF)) significantly improved SOC, MBC, DOC, and POC contents and seven hydrolytic enzyme activities (α-1,4-glucosidase, β-1,4-glucosidase, β-1,4-xylosidase, cellobiohydrolase, L-leucine aminopeptidase, β-1,4-N-acetylglucosaminidase, phosphatase) at different temperatures, compared with the mineral fertilized treatment (SMF) and CK. However, oxidoreductases (peroxidase and phenol oxidase) showed the opposite trend with hydrolytic enzyme activities and had higher values in SMF and CK treatments; (3) SOC, MBC, DOC, POC, and most of the soil enzyme activities decreased with increasing temperature; (4) RDA revealed that the dominant factors of SOC and soil labile organic carbon fractions affecting soil enzyme activities were POC and SOC at 5°C, DOC and POC at 15°C, DOC and SOC at 25°C, and MBC, DOC, and SOC at 35°C. In conclusion, temperature changes significantly altered soil enzyme activities by driving changes in the rates of SOC decomposition and the fractions of soil labile organic carbon. Our conclusions have clear implications for soil ecosystem and biogeochemical cycles under climate change.

Bacterial community structure in atrazine treated reforested farmland in Wuying China

The Grain for Green (GFG) Project in China is currently the largest environmental rehabilitation project aimed at turning low-yielding farm land to forests and pastures. Such conversion of land use type also promotes remediation of the polluted environment. Soil microbes reflect soil function and are therefore considered an essential component of ecosystem restoration. To evaluate the environmental effects of converting atrazine polluted farmland to secondary forest, we determined soil chemical properties, soil bacterial communities and their responses to three types of land use (primary forest, PF; secondary forest, SF; farm land, FL) in Wuying, China. Our results showed that soil organic matter significantly decreases in the order PF>SF>FL. Bacterial 16S rRNA gene 454 pyrosequencing revealed that the soil bacterial diversity level remained unchanged. However between FL and the two forested sites, we observed an increase of Actinobacteria, β-proteobacteria and Firmicutes; and a decrease of Acidobacteria and Verrucomicrobia, while in SF the bacterial community structure was similar to PF. We conclude that reforestation permits bacterial community, resetting from FL back to a state that resembles natural conditions. In addition, 20 years of natural attenuation degraded soil atrazine residues in SF but traces remained in the soil. Reforestation generally resulted in favorable ecological impacts on soil quality and the bacterial community compared with active farm fields.

Long-term cropping system impact on quality and productivity of a Dark Brown Chernozem in southern Alberta

Smith, E. G., Janzen, H. H. and Larney, F. J. 2015. Long-term cropping system impact on quality and productivity of a Dark Brown Chernozem in southern Alberta. Can. J. Soil Sci. 95: 177–186. Long-term cropping system studies offer insights into soil management effects on agricultural sustainability. In 1995, a 6-yr bioassay study was superimposed on a long-term crop rotation study established in 1951 at Lethbridge, Alberta, to determine the impact of past cropping systems on soil quality, crop productivity, grain quality, and the relationship of yield productivity to soil quality. All plots from 13 long-term crop rotations were seeded to wheat (Triticum aestivum L.) in a strip plot design [control, nitrogen (N) fertilizer]. Prior to seeding, soils were sampled to determine soil chemical properties. Total wheat production for the last 4 yr of the study was used as the measure of productivity. The 1995 soil analysis indicated crop rotations with less frequent fallow and with N input had higher soil quality, as indicated by soil organic carbon (SOC) and light fraction carbon (LF-C) and N (LF-N). SOC had a positive relationship to total wheat yield, but was largely masked by the application of N in this bioassay study. Frequent fallow in the previous crop rotation lowered productivity. The concentration of LF-C had a negative relationship, whereas LF-N had a positive relationship to total wheat yield, with and without N fertilization in this bioassay study. Grain N concentration was higher with applied N and when the long-term rotation included the addition of N by fertilizer, livestock manure, annual legume green manure or legume hay. This study determined that long-term imposition of management practices have lasting effects on soil quality and crop productivity.

The effects of landscape attributes and plant community on soil chemical properties in rangelands

This study addressed the effect of landscape attributes and plant community type on the spatial distribution of soil chemical properties in an alpine rangeland in a semiarid area of Iran. To identify the effects of landscape attributes on soil chemical properties, the present study collected and analyzed information from air photos, satellite images, field survey, and the laboratory using statistical analyses. Land stratification allowed the study area to be subdivided into Land Unit Tracts (LUT), according to specified criteria including landform attributes (slope, aspect, and altitude), and vegetation type. A factorial model on the basis of a completely randomized design was used to analyze the data collected from 234 LUT. The interrelationships between soil chemical properties and landscape attributes were investigated and interpreted based on statistical analysis and expert knowledge. Most chemical properties of the 0- to 10-cm topsoil including EC, OC%, total N%, P, and K significantly related to slope gradient. Soil chemical properties including the grouping described as nutrient elements (CEC, N, P, K, and OC), and pH significantly related to aspect of slope. In addition lower soil temperature and less moisture evaporation on a north-facing slope (shady aspect) resulted in less organic matter decomposition and consequently more organic carbon and total nitrogen accumulation in the soil. Consequently, the soil nutrient pool and general fertility on north-facing slopes was greater than on south-facing slopes. The interdependency of landscape attributes, plant community, and soil chemical properties led to a variety of species, vegetation types, and plant communities existing in the study area. In this research, vegetation type was highly significantly related to all the determined soil chemical properties except for cation exchange capacity.

Appropriateness of Management Zones for Characterizing Spatial Variability of Soil Properties and Irrigated Corn Yields across Years

Recent precision-agriculture research has focused on use of management zones (MZ) as a method for variable application of inputs like N. The objectives of this study were to determine (i) if landscape attributes could be aggregated into MZ that characterize spatial variation in soil chemical properties and corn yields and (ii) if temporal variability affects expression of yield spatial variability. This work was conducted on an irrigated cornfield near Gibbon, NE. Five landscape attributes, including a soil brightness image (red, green, and blue bands), elevation, and apparent electrical conductivity, were acquired for the field. A georeferenced soil-sampling scheme was used to determine soil chemical properties (soil pH, electrical conductivity, P, and organic matter). Georeferenced yield monitor data were collected for five (1997–2001) seasons. The five landscape attributes were aggregated into four MZ using principal-component analysis of landscape attributes and unsupervised classification of principal-component scores. All of the soil chemical properties differed among the four MZ. While yields were observed to differ by up to 25% between the highest- and lowest-yielding MZ in three of five seasons, receiving average precipitation, less-pronounced (≤5%) differences were noted among the same MZ in the driest and wettest seasons. This illustrates the significant role temporal variability plays in altering yield spatial variability, even under irrigation. Use of MZ for variable application of inputs like N would only have been appropriate for this field in three out of the five seasons, seriously restricting the use of this approach under variable environmental conditions.

Appropriateness of Management Zones for Characterizing Spatial Variability of Soil Properties and Irrigated Corn Yields across Years

Recent precision‐agriculture research has focused on use of management zones (MZ) as a method for variable application of inputs like N. The objectives of this study were to determine (i) if landscape attributes could be aggregated into MZ that characterize spatial variation in soil chemical properties and corn yields and (ii) if temporal variability affects expression of yield spatial variability. This work was conducted on an irrigated cornfield near Gibbon, NE. Five landscape attributes, including a soil brightness image (red, green, and blue bands), elevation, and apparent electrical conductivity, were acquired for the field. A georeferenced soil‐sampling scheme was used to determine soil chemical properties (soil pH, electrical conductivity, P, and organic matter). Georeferenced yield monitor data were collected for five (1997–2001) seasons. The five landscape attributes were aggregated into four MZ using principal‐component analysis of landscape attributes and unsupervised classification of principal‐component scores. All of the soil chemical properties differed among the four MZ. While yields were observed to differ by up to 25% between the highest‐ and lowest‐yielding MZ in three of five seasons, receiving average precipitation, less‐pronounced (≤5%) differences were noted among the same MZ in the driest and wettest seasons. This illustrates the significant role temporal variability plays in altering yield spatial variability, even under irrigation. Use of MZ for variable application of inputs like N would only have been appropriate for this field in three out of the five seasons, seriously restricting the use of this approach under variable environmental conditions.