Improvement Of Fulvic Acids Application On Properties Of Three Typical Obstacle Soils And Crop Growth

Fulvic acid(FA)is the extractable essential elements of humic substance available in soil solution and considered as the most valuable and initial organic constituent of soil.It is the ultimate part of soil organic structure,and have major effect on physiological,biological and chemical properties of soil and also contains many beneficial elements for increasing the crop yields.FA also reduced the soil erosion,soil degradation and improves the organic matter.Many studies suggest that FA directly influence soil fertility.However,its mechanism,chemical compositions,application dosages of are still unclear.In present study,we performed pot experiment,in which effect of FA derived from natural and plant materials in solid and liquid form were examined on the soil obstacle factors such as: soil organic carbon,soil organic carbon fraction,available and total nutrients content,physiological characteristics of plants,plant growth performances,soil aggregations and distribution soil organic carbon and total nitrogen content in between the aggregate's fractions were analyzed.Summer maize and winter wheat were cultivated on AL,IR,and SH soils,which are Udic,Aridisols and Podzoluvisols soils according to soil Taxonomy of China and are considered as low productive and less fertile soils of south-east region of the country.Experiment carried out with one of the three different treatments of FA derived from different parent material plant-derived solid(S),natural-derived liquid(NL),and plant-derived liquid(P)applied at respective rates of 0.25%,0.50%,and 0.50% as well as control applied at 0% and taken from shandong Quan Linjia fertilizer Co.Ltd(Shandong,China).The results showed that soil organic carbon and light fraction C were greater by 29% to 21% and 38% to 21%,respectively,among the treatments compared to that of the control.Similarly,available N content was significantly greater in the P treatment,and AP content was also significantly greater in the S treatment.In contrast,available K and extractable Mg contents were lower,as well as organic–inorganic degree complexes and organic–inorganic composites in the S,NL,and P treatments compared with those of the control.Further results showed that NL and P FAs accelerated plant growth of AL soil,while S limited plant growth.The results showed that soil organic carbon content was increased by 20%,11.6% and 24%,compared with initial soil organic carbon content,however light fraction C and heavy fraction C content were increased by 37% in SH soil and 12.4% in AL soil.Greater amounts of soil organic C and its labile fractions were observed in SH soil comparing with AL and IR soils.Similarly,soil pH was decreased at SH and IR soil and electrical conductivity was increased comparing with initials pH and electrical conductivity.Comparing with initial nutrients PDL FA significantly increased the nutrients content of AL,IR and SH soils.Available phosphorus(P),available potassium(K)content and total P were significantly higher at IR soil comparing with SH and AL,however total nitrogen content,total K and extractable Ca and Mg content were significantly higher in SH soil than in AL and IR soil.In contrast,the contents of organic-inorganic degree compounds and organic-inorganic complexes were lower in SH soil compared with those in AL and IR soil.Further results showed that maize performs better when grown on SH soil treated with PDL FA than on AL and IR soils.FA indirectly influence the plant growth characteristics,results showed that in SH soil,the diameter of maize and spike weight of wheat were significantly decreased.At the same time,increased at NL and P in AL,S and P in IR soil.Similarly,plant height and biomass content of maize was increased at NL and P in AL,S and P in IR,and NL in SH soil,however,decreased at S in AL soil,wheat height was significantly increased 1% to 5 % in AL and 5% at NL in IR soil and non-significantly decreased in SH soil in between the treatments compare with control.In contrast,wheat biomass increased in between the treatments in AL,on NL and P in IR and SH soils and decreased at S.Maize grain weight was increased at P in AL and IR and NL in SH soil,however,wheat grain weight was decreased in between the treatments.In contrast,nutrients uptake of maize was significantly increased in AL and IR soil and non-significantly in SH soils,however,wheat nutrients were significantly increased in between the treatments,K uptake was observed non-significant in SH soil.The mass distribution was varied at different fraction in between the soils,the greater mass was observed at <0.053 mm in AL,0.25-0.053 mm in IR and 2-0.25 mm fraction in SH soils,however,water stable aggregates(WSA)was greater at S in between the soils and mean weight diameter(MWD)value was greater at P in AL,S in IR and NL in SH soils.Similarly,the soil organic carbon and total nitrogen distribution of aggregates fractions were greater at NL and P in between the soils,total nitrogen was found lower in aggregate in between the soils.Overall this was observed that NL and P increased the physical properties,organic carbon fractions,plant growth characteristics and distribution of soil organic carbon and total nitrogen content in between aggregates however,S limited the plant growth and physical properties.Our study provides empirical evidence that addition of FA from NL and P had more positive effects on soil properties and plant growth characteristics than from S.This investigation suggests that application of in Liquid form can improve the nutrients availability and affect other important soil obstacle factors.The field experiment can be conducted at different concentration level of liquid FA but dosage should not more the 1% which is become as toxic for plants to grow.