Changes In Soil Chemical Properties Research Articles

Spatiotemporal changes in arbuscular mycorrhizal fungal communities under different nitrogen inputs over a 5-year period in intensive agricultural ecosystems on the North China Plain.

Appropriate nitrogen (N) management is important to minimize N losses from intensively managed agricultural ecosystems. Understanding the community structure of arbuscular mycorrhizal fungi (AMF) in response to N management can be of great ecological significance, particularly with the recent emphasis on the role of AMF in N cycling. A comprehensive study of both the vertical distribution of AMF in the soil profile and the temporal changes in community structure in maize roots was conducted over a 5-year period at a field site on the North China Plain. The N treatments consisted of zero N, conventional farming practice, and optimum N based on an in-season soil Nmin test. Terminal restriction fragment length polymorphism and clone sequencing were used to analyse the AMF community. Optimum N mitigated the decline in richness of AMF in the conventional N treatment in the surface soil. Diverse and species-rich AMF communities occurred deep in the soil profile. A significant difference in AMF community structure was observed between the control and fertilizer N treatments but not between the two N application strategies. AMF communities deeper in the soil profile were subsets of those richer communities in the surface soil and the loss of AMF taxa was mostly due to the absence of rare taxa. Soil pH and Nmin contents were major soil properties affecting the soil AMF communities among the N treatments while vertical distribution was influenced mainly by soil electrical conductivity. Crop phenology had a stronger influence than N treatment on the temporal shifts in AMF communities in maize roots. Our results provide evidence for the importance of N management in maintaining AMF diversity. Changes in soil chemical properties due to N fertilization, in particular declining soil pH, should be integrated in N management strategies to reduce the negative impacts on AMF communities induced by N fertilization. Excessive N inputs induced significant changes in soil physicochemical properties, especially soil acidification, and may have negative impacts on AMF communities.

Contrasting Effects of Sorghum Biochars and Sorghum Residues on Soil Chemical Changes of Coastal Plains Ultisols With Winter Wheat

Although most soil properties were improved following application of crop residues and/or pyrolyzed crop residues, there is still a need to pursue additional research that will improve our understanding of the impact of soil fertility enhancement because the effect could vary greatly between uncharred sorghum (Sorghum bicolor L.) residues and pyrolyzed sorghum residues (SR). We hypothesized that sorghum biochars (SB) would deliver more significant impact on soil chemical changes than SR. The objective of this study was to evaluate the contrasting effects of SR and SB with or without supplemental inorganic P on soil chemical changes of Coastal Plains Ultisols with winter wheat. The application rates for SR and SB based on 13.5 Mg ha−1 yield goal for wheat were 13,000 and 5,200 kg · ha−1, respectively. Inorganic P was added at the rate of 40 kg P · ha−1. Our results fully support our hypothesis that SB would deliver more positive effect on the changes of soil chemical properties than the SR. Most of the chemical properties of soils were significantly affected by sorghum treatments (SB + SR) and also varied widely between soil types. Overall, application of SB had small, but significant effects on soil pH, soil electrical conductivity, total carbon, and total nitrogen. Quite notably was the significant difference of these soil properties between soil types. Other aspects of soil chemical changes including extractable P, K, Ca, Mg, Al, and Fe were significantly affected by sorghum treatments. Our results have demonstrated widely differing and contrasting effects between SB and SR on changes in soil chemical properties of Coastal Plains Ultisols.

Biochar impacts soil microbial community composition and nitrogen cycling in an acidic soil planted with rape.

Biochar has been suggested to improve acidic soils and to mitigate greenhouse gas emissions. However, little has been done on the role of biochar in ameliorating acidified soils induced by overuse of nitrogen fertilizers. In this study, we designed a pot trial with an acidic soil (pH 4.48) in a greenhouse to study the interconnections between microbial community, soil chemical property changes, and N2O emissions after biochar application. The results showed that biochar increased plant growth, soil pH, total carbon, total nitrogen, C/N ratio, and soil cation exchange capacity. The results of high-throughput sequencing showed that biochar application increased α-diversity significantly and changed the relative abundances of some microbes that are related with carbon and nitrogen cycling at the family level. Biochar amendment stimulated both nitrification and denitrification processes, while reducing N2O emissions overall. Results of redundancy analysis indicated biochar could shift the soil microbial community by changing soil chemical properties, which modulate N-cycling processes and soil N2O emissions. The significantly increased nosZ transcription suggests that biochar decreased soil N2O emissions by enhancing its further reduction to N2.

Micronutrientes e reação de um latossolo cultivado com cana-de-açúcar fertirrigada

The use of fertigation on sugar-cane can promote changes in soil chemistry. Thus, the aim of this study was to evaluate changes in soil micronutrients and soil reaction in sugar cane plantation with nitrogen and potassium fertigation at different levels. This experiment was carried out in an Oxisol from the experimental area of Federal Institute of Education, Science and Technology Goiano – Goiás State. Was used RB 85-5453 sugar cane variety and irrigated with different levels (0, 25, 50, 75 and 100 % of the crop water requirement), with and without nitrogen (0 and 100 kg N ha -1 ). Sugar cane productivity was evaluated, as well as, the levels of boron, zinc, copper, iron, manganese, hydrogen + aluminum, soil organic matter, cation exchange capacity, base saturation and soil pH, after nitrogen fertilizer application in surface (0 to 0.30 m) and subsurface (0.30 0.60 m). Fertigation combined with different irrigation levels caused soil chemical changes, both soil reaction and soil micronutrient content. Irrigation levels factor had significant effect on changing the of cation exchange capacity, hydrogen + aluminum, copper and iron contents. Fertigation factor influenced significantly zinc, hydrogen + aluminum, base saturation and soil pH, and caused soil acidity. The biggest changes in soil chemical properties were due to soil layers analyzed. Fertigation increased the sugar cane productivity.

Soil substrate utilization pattern and relation of functional evenness of plant groups and soil microbial community in five low mountain NATURA 2000

Species rich, semi-natural grassland systems provide several ecosystem functions. The goal was to assess how aboveground composition and evenness affects soil substrate utilization pattern and soil microbial functional evenness. At five German NATURA 2000 grassland sites, the interactions of plant functional groups (graminoids, forbs and legumes) and belowground microbial functional evenness were investigated in relation to soil properties and sampling date. Functional evenness of soil microorganisms was measured with high spatial resolution by community level physiological profiling (CLPP) using multi-SIR (substrate-induced respiration) at three sampling dates during the vegetation period. Evenness indices were used to compare plant functional group diversity and soil microbial functional diversity. All sites differed in the consistently high soil microbial functional evenness, which was strongly predicted by soil pH, but not by plant functional groups or aboveground plant dry matter production. However, soil microbial functional evenness was particularly decreased by an increasing legume proportion and showed seasonal changes, probably driven by shifts in resource availability and soil water content. Our results suggest that changes in soil chemical properties or in a single key plant functional group may have stronger effects on soil microbial functional evenness than changes in plant functional group evenness.

Total, cold and hot water extractable organic carbon in soil profile: impact of land-use change

The content of labile, especially water extractable organic carbon (WEOC) is a sensible indicator of soil organic matter quality. The main objectives of this study were: i) to investigate the profile changes of cold and hot water extractable organic carbon in forest and arable soils; ii) to evaluate the correlation between these labile fractions of soil organic matter and total organic carbon content. The experiments were carried out on a Gleyic Albeluvisol (ABg) in the upper part of Dniester basin, Western Ukraine. The soil samples were taken from 50-cm depth soil profile with 5-cm step. Total organic carbon (TOC), cold water extractable organic carbon (CWEOC) and hot water extractable organic carbon (HWEOC) contents in soil were determined as well as pH (H 2 O) and electrical conductivity of soil:water suspensions. The results of this study showed that in 0–50 cm layer of arable soil TOC content decreased by 32%, CWEOC – by 23% and HWEOC – by 74% compared to forest soil that confirmed a high informative role of HWEOC fraction. The profile changes of WEOC percentage were analysed. They also show that HWEOC is much more informative indicator of soil organic matter quality than CWEOC. The most prominent changes of soil chemical properties, TOC, CWEOC and HWEOC contents in response to deforestation were observed in the top 5-cm soil layer. We suggested this thin soil layer to be defined as soil stress-sensitive zone.

Chemical composition of soils on post-agricultural and forest sites before and after sawdust addition against the background of weather elements

Abstract We analysed changes in soil chemical properties (pH, C:N, N, P, K, Ca, Na) inside two forest areas chosen for renewal (Lubartów A and B) and within one post-agricultural site (Świerczyna) designated for afforestation with Scots pine. The experimental plots were located in areas known as persistent cockchafer grub spots. The Lubartów A site was not fenced and showed signs of wild boar activity. Analyses were carried out in the autumn of 2011 and spring 2012, prior to pine sawdust application to the soil and before tree planting, respectively, and again one year later in May 2013. Precipitation as well as air and soil temperatures were recorded throughout the experimental period. We found that soil temperature and humidity, determined by changes in weather, differences in soil chemical properties between forest and agricultural sites as well as sawdust treatments differentially affected soil reaction, C:N ratios and nutrient content. In the unfenced area (Lubartów A), the content of nutrient forms available to plants decreased no more under sawdust treatment than under control conditions. In the remaining areas, sawdust treatment caused an increase or no change in soil concentrations of the investigated nutrients. Under suitable temperature and humidity conditions, sawdust can represent a significant source of energy-rich compounds promoting diversified edaphone activity, which appears to be the main reason for changes in soil nutrient content.

Influence of Lime and Gypsum on Growth and Yield of Upland Rice and Changes in Soil Chemical Properties

Upland rice is an important crop in the cropping systems of South America, including Brazil. Two greenhouse experiments were conducted to determine influence of lime and gypsum on yield and yield components of upland rice and changes in the chemical properties of an Oxisol. The lime rates used were 0, 0.71, 1.42, 2.14, 2.85, and 4.28 g kg−1 soil. The gypsum rates were 0, 0.28, 0.57, 1.14, 1.71, and 2.28 g kg−1. Lime as well as gypsum significantly increased plant height, straw and grain yield, and panicle density in a quadratic fashion. Adequate lime and gypsum rates for maximum grain yield were 1.11 g kg−1 and 1.13 g kg−1, respectively. Plant height, straw yield, and panicle density were positively related to grain yield. Lime as well as gypsum application significantly changed extractable calcium (Ca), magnesium (Mg), hydrogen (H)+aluminum (Al), base saturation, and effective cation exchange capacity. In addition, liming also significantly increased pH, extractable phosphorus (P) and potassium (K), calcium saturation, magnesium saturation, and potassium saturation. Optimum acidity indices for the grain yield of upland rice were pH 6.0, Ca 1.7 cmolc kg−1, base saturation 60%, and calcium saturation 47%. In addition, upland rice can tolerate 42% of acidity saturation.

Effect of lime and sewage sludge fertilisation on tree and understory interaction in a silvopastoral system

The productivity of the components of a silvopastoral system could be limited by the low soil fertility and the presence of shrubs in the land before planting. However, the understory vegetation can be modified by improving soil chemical properties when lime and organic fertilizers such as sewage sludge are applied. This study evaluated the effect of liming and the application of two doses of sewage sludge (50kgtotalNha−1 or 100kgtotalNha−1) on changes in soil chemical properties, tree growth and understory production as compared to the no fertilisation treatment in a silvopastoral system established in a reforested area with Pinus radiata D. Don. The results of this experiment show that the improved soil fertility caused by liming and fertilisation with sewage sludge modifies the proportion of the herbaceous/shrubs component in the understory, and promotes facilitation mechanisms which have a positive impact on the understory forage quality, tree growth as well as reducing fire risk.

The Effect of Dredged Soil Improvement on Soil Chemical Conditions and Plant Growth at the Slope of Saemangeum Sea Dike

This study was conducted to determine the changes in soil chemical properties and the growth of seedling according to the different dredged soil improving methods at slope of Saemangeum sea dike. Undersea dredged soil was improved by five different methods. Seedlings of Ulmus davidiana var. japonica, Chionanthus retusa, Celtis sinensis, and Pinus thunbergii were planted after 9 month of experience site installation, then soil pH, NaCl concentration in soil, soil organic matter (SOM), and survival rate and height of seedling was measured. Initial soil pH was highest in the control plot but it decreased to the similar level with other soil improving plots after 35 months. There were no differences in NaCl concentration between the control and soil improving plots, and it showed decreasing tendency during the study period. In the control plot, initial SOM was lowest among that of other plots during the study period. The survival rate of 36 months after planting of P. thunbergii was highest among the species. The gap of the tree growth of P. thunbergii between the control plot and the soil improving plots was small, however, other species showed relatively higher tree height in the soil improving plots than the control plots. Creation forest with P. thunbergii might be a cost effective afforestation in coastal reclaimed land since it rarely needs additional improvement of dredged soil.

Influence of Lime and Gypsum on Yield and Yield Components of Soybean and Changes in Soil Chemical Properties

Soybean is one of the most important legume crops in the world. Two greenhouse experiments were conducted to determine the influence of liming and gypsum application on yield and yield components of soybean and changes in soil chemical properties of an Oxisol. Lime rates used were 0, 0.71, 1.42, 2.14, 2.85, and 4.28 g kg−1 soil. Gypsum rates applied were 0, 0.28, 0.57, 1.14, 1.71, and 2.28 g kg−1 soil. Lime as well as gypsum significantly increased grain yield in a quadratic fashion. Maximum grain yield was achieved with the application of 1.57 g lime per kg soil, whereas the gypsum requirement for maximum grain yield was 1.43 g per kg of soil. Lime significantly improved soil pH, exchangeable soil calcium (Ca) and magnesium (Mg) contents, base saturation, and effective cation exchange capacity (ECEC). However, lime application significantly decreased total acidity [hydrogen (H) + aluminum (Al)], zinc (Zn), and iron (Fe) contents of the soil. The decrease in these soil properties was associated with increase in soil pH. Gypsum application significantly increased exchangeable soil Ca, base saturation, and ECEC. However, gypsum did not change pH and total acidity (H + Al) significantly. Adequate soil acidity indices established for maximum grain yield with the application of lime were pH 5.5, Ca 1.8 cmolc kg−1, Mg 0.66 cmolc kg−1, base saturation 53%, Ca saturation 35%, and Mg saturation 13%. Soybean plants tolerated acidity (H + Al) up to 2.26 cmolc kg−1 soil. In the case of gypsum, maximum grain yield was obtained at exchangeable Ca content of 2.12 cmolc kg−1, base saturation of 56%, and Ca saturation of 41%.

Long-term effects of eight soil health treatments to control plant-parasitic nematodes and Verticillium dahliae in agro-ecosystems

There is an urgent need to test and develop sustainable methods for management of soil pathogens, such as the root-lesion nematode Pratylenchus penetrans and the soil fungus Verticillium dahliae. Ultimately this should be investigated with a multidisciplinary approach, with long-term measurements of biological and chemical parameters and their final impact on crop yield under field conditions. The present study focusses on eight soil health treatments (compost, chitin, marigold, grass–clover, biofumigation, anearobic soil disinfestation, a physical control method and a combination of marigold, compost and chitin) and two control treatments (a chemical control with 300L/ha Metam sodium and un untreated control). These 10 treatments were studied for their effects on soil chemical quality, soil pathogens and their impact on the yield of potato, lily and carrots during 6 years. The present study did demonstrate that in comparison to chemical control, additions of chitin, anaerobic soil disinfestation and marigold are already excellent alternatives for the control of plant-parasitic nematodes and V. dahliae. We also demonstrated that grass–clover, biofumigation, Cultivit and compost are not effective alternatives for chemical control yet and further development is needed. All treatments caused a yield increase in comparison with the control. The biggest increases of more than 60% were found for the treatments with chitin. Furthermore it was demonstrated that these yield increases were probably less influenced by changes in chemical soil properties, but the consequence of changes in the soil biota, in this case especially the effective control of P. penetrans and V. dahliae. Furthermore it has been demonstrated that most of these soil health treatments could already be implemented in an arable crop rotation and probably adapted for many areas of the world where other alternatives, such as solarisation or soil flooding, are not feasible or too risky.

Changes in Soil Chemical Properties in Response to Application of Phosphorus Sources in Legume Sorghum Cropping Systems

Changes in Soil Chemical Properties in Response to Application of Phosphorus Sources in Legume Sorghum Cropping Systems Beldina A. Tunya; Joyce J. Lelei; Josephine P. Ouma; Ombui, P.N; Onwonga, R.N. Abstract Field experiments to evaluate effect of phosphorus (P) fertilizers and integration of legumes in sorghum cropping systems on soil pH, available nitrogen (N) and P, were conducted in Njoro Kenya during the short (SRS) and long rain seasons (LRS) of 2012 and LRS of 2013. The experiments comprised either lupin or chickpea grown with sorghum. The design was a split plot in a randomized complete block design. Main plots were cropping systems; sorghum monocrop, legume - sorghum rotation and legume- sorghum intercrop. Subplots comprised P sources (60 kg P ha- 1); triple super phosphate (TSP) and minjingu phosphate rock (MPR). Application of TSP resulted in significantly higher nutrient concentrations in the soil than MPR addition in the first season. In the second and third seasons, the performance of MPRs approached that of TSP. Legume crops due to their release and accumulation of carboxylic acid lowered the pH to below 5.5 thus making solubilization of MPR and availability of P possible. Intercropping sorghum with lupin or chickpea with application of MPR gave comparable results with use of TSP. Since MPR is cheaper than TSP, growing lupin or chickpea in intercropping system with sorghum with application of MPR is recommended for improved chemical properties. Full Text: PDF DOI: 10.15640/jaes.v3n4a11

Microbial Community Structure of Paddy Soil Under Long-term Fertilizer Treatment Using Phospholipid Fatty Acid (PLFA) Analysis

Understanding the microbial community structure of agricultural soils is important for better soil management in order to improve soil quality. Phospholipid fatty acid analysis has been popularly used in determining the microbial community structure in different ecosystems. The microbial community structure of paddy soil under long-term fertilizer treatments was investigated after 45 years using PLFA analysis. Treatments were control (no fertilization, Con), compost (COM), NPK, NPK+compost (NPKC), PK, NK, and NP. Soil chemical properties were mainly affected by the addition of compost and inorganic P fertilizer. Total nitrogen and organic matter contents were significantly higher in treatments with compost while available <TEX>$P_2O_5$</TEX> and exchangeable calcium were significantly higher in treatments with added inorganic P fertilizer. It was found that microbial communities were responsive to the different fertilizer treatments. PLFA results showed that the soils were dominated by gram-negative bacteria, followed by the actinomycetes, then gram-positive bacteria, and fungi. Principal component analysis of the soil chemical properties and PLFA composition proved to be a more reliable tool because it was more responsive to the changes in soil chemical properties.

Propriedades químicas do solo na bacia hidrográfica do rio Vacacaí-Mirim

Os teores de metais em solos têm aumentado gradativamente com a modernização da agricultura ocorrida nos últimos anos. A ação antrópica desempenhada pelo homem na natureza é a principal causa desse fenômeno. Com base nisso, o presente estudo tem por objetivo avaliar alterações nos atributos químicos do solo em decorrência de diferentes usos e ocupações na bacia hidrográfica do Rio Vacacaí-Mirim. A técnica utilizada para análise foi a EDXRF, em que os valores foram espacializados com auxílio do software Surfer 10. Os valores de Bário variaram do limite de detecção (LD) a 7.608,27 mg/kg-1 com média de 1.286,71 ± 2.295,18 mg/kg-1, a concentração de Fósforo variou do LD a 2.327,02 mg/kg-1 com média de 676,45 ± 700,05 mg/kg-1, Manganês variou do LD a 5.533,51 mg/kg-1 com média de 1.057,34 ± 1.380,81 mg/kg-1, os valores de Silício variaram de 229.114,70 a 832.568,70 mg/kg-1 com média de 696.134,25 ± 144.950,56 mg/kg-1, a concentração de Zinco variou do LD a 429,98 mg/kg-1 com média de 145,725 ± 123,78 mg/kg-1. Com base nos resultados obtidos, é possível identificar que a concentrações dos metais estudados e os usos do solo estão estritamente ligados, visto que as concentrações são maiores nas áreas que possuem usos agrícolas, que demandam maiores quantidades de produtos químicos. Sendo assim, pôde-se observar que os solos sob os usos de arroz, soja e pastagem apresentaram maior influência na concentração do elemento bário, já o fósforo teve maior influência dos solos sob uso de pastagem e soja.

Changes of Soil Chemical Properties During Rice Straw Decomposition in Different Types of Acid Sulphate Soils

Changes of Soil Chemical Properties During Rice Straw Decomposition in Different Types of Acid Sulphate Soils

Erosion control blankets, organic amendments and site variability influenced the initial plant community at a limestone quarry in the Canadian Rocky Mountains

Abstract. Season of seeding and soil amendment with manure mix, wood shavings and erosion control blankets were evaluated over two growing seasons to determine their effect on soil properties and native grass establishment at a Canadian limestone quarry and lime processing plant. A season (fall, spring) of soil amending and seeding did not significantly affect revegetation or soil properties. Site characteristics such as slope, aspect, initial soil nutrients and surrounding plant communities influenced early plant community development and overall effects of soil treatments. Erosion control blankets resulted in the highest seeded plant cover and the lowest non-seeded plant cover despite not significantly changing soil chemical properties. Total nitrogen and carbon significantly increased establishment of seeded grasses and non-seeded species. Increased nitrogen and carbon in the constructed soils were best achieved through addition of manure. Wood shavings did not favour establishment of vegetation and resulted in similar, and in some cases less, vegetation than the controls. Assisted revegetation increased plant cover from &lt; 6 to 50% and reduced cover of non-seeded species. Amendments that modified both chemical and physical soil conditions were best to increase vegetation establishment in the harsh conditions of the quarry.

Possible utilization of ash from meat and bone meal and dried distillers grains gasification as a phosphorus fertilizer: crop growth response and changes in soil chemical properties

Purpose Gasification process is regarded as a viable option for disposal of various types of organic waste. Its application to meat and bone meal (MBM) and dried distillers grains (DDG) is a new concept that is recently receiving more attention as possible strategy for safe recycling of these materials to benefit from their energy and nutrient value. Besides, this process produces ash that is rich in phosphorus (P) and may be suitable for utilization as a P fertilizer. Therefore, the objective of this study was to evaluate the effectiveness of these specific types of ashes as P fertilizer via evaluating their direct effect on canola growth, P uptake, apparent P recovery and changes in some selected soil chemical properties after their addition to a P-deficient soil.

Soil Nutrients and Other Major Properties in Grassland Fertilized with Nitrogen and Phosphorus

Understanding how nutrient distribution relates to soil depth is essential for improving fertilization practices for grasslands. This study evaluated the distribution of P, other elements, and selected soil properties at 0- to 5-cm and 5- to 15-cm layers in a grass sward following several years of N and P fertilization. Soil samples were collected in the spring of 2010 from a timothy grass sward (Phleum pratense L.) established in 1998 on a gravely-sandy loam soil. Sixteen combinations of P (0, 15, 30, and 45 kg ha−1) as triple superphosphate and N (0, 60, 120, and 180 kg ha−1) as calcic ammonium nitrate were broadcast annually from 1999 to 2006 in a split-plot design with P as main plots and N as subplots. Concentration of three soil P indicators [water (CP), Mehlich-3 (PM3), and acid oxalate (POx) extractable P] and total phosphorus (PT) were greater in the 0- to 5-cm than in the 5- to 15-cm layer. Differences in concentration of CP, PM3, POx, and PT between the two soil layers increased with increasing P applications. The NH4OAc extractable Ca and Mg concentrations were significantly greater in the 0- to 5-cm soil layer compared with the 5- to 15-cm soil layer. The NH4OAc extractable K was significantly decreased by N application being greater in the 5- to 15-cm soil layer than in the 0- to 5-cm soil layer. Soil pH decreased and the concentration of Mehlich-3 Al increased with increasing N applications only in the 0- to 5-cm layer. This study demonstrated that several years of P fertilizer in grasslands could increase soil available P in the 0- to 5-cm layer, possibly due to lack of mixing and the low mobility of P. Our results also suggest that changes in soil chemical properties induced by N fertilizer in grasslands could be heightened at the 0- to 5-cm layer.

Physiological Responses of Tomato Plants and Soil Microbial Activity in Salt Affected Greenhouse Soil

Crop productivity decreases globally as a result of salinization. However, salinity impact on greenhouse-grown crops is much higher than on field-grown crops due to the overall concentrations of nutrients in greenhouse soils. Therefore, this study was performed to determine the short-term changes in growth, photosynthesis, and metabolites of tomato plants grown in greenhouse under heavily input of fertilizers evaluated by microbial activity and chemical properties of soils. The soils (< 3, 3.01~6, 6.01~10 and > 10.01 dS <TEX>$m^{-1</TEX><TEX>}$</TEX>) from farmer's greenhouse fields having different fertilization practices were used. Results showed that the salt-accumulated soil affected adversely the growth of tomato plants. Tomato plants were seldom to complete their growth against > 10.0 dS <TEX>$m^{-1}$</TEX> level of EC. The assimilation rate of <TEX>$CO_2$</TEX> from the upper fully expanded leaves of tomato plants is reduced under increasing soil EC levels at 14 days, however; it was the highest in moderate or high EC-subjected (3.0 ~ 10.0 dS <TEX>$m^{-1}$</TEX>) at 28 days. In our experiment, soluble sugars and starch were sensitive markers for salt stress and thus might assume the status of crops against various salt conditions. Taken together, tomato plants found to have tolerance against moderate soil EC stress. Various EC levels (< 3.0 ~ 10.0 dS <TEX>$m^{-1}$</TEX>) led to a slight decrease in organic matter (OM) contents in soils at 28 days. Salinity stress led to higher microbial activity in soils, followed by a decomposition of OM in soils as indicated by the changes in soil chemical properties.