[Objective] The aim was to detect effects of biochar on soil enzyme activity and mechanism. [Method] Soils were sampled from experimental fields of Shanxi Academy of Agricultural Sciences and added with charcoals in d...[Objective] The aim was to detect effects of biochar on soil enzyme activity and mechanism. [Method] Soils were sampled from experimental fields of Shanxi Academy of Agricultural Sciences and added with charcoals in different types in order to analyze dynamic changes of alkaline phosphatase and cellulase activities and effects of charcoals on soil enzyme activities. [Result] By applying charcoal, enzyme activity of soil samples all improved and the increase degree was higher of alkaline phosphatase than cellulase activity. Mid-temperature charcoal at 8% is the best. [Conclusion] The research provides references for effects of biochar on physi- cal and chemical properties.展开更多
The transformation of organic P(Po) from organic manures in two types of soils (ultisol and entisol) and the influences of external addition of organic substance or inorganic P(Pi) on Po under the condition of the 60%...The transformation of organic P(Po) from organic manures in two types of soils (ultisol and entisol) and the influences of external addition of organic substance or inorganic P(Pi) on Po under the condition of the 60% maximum water capacity were investigated.The results obtained from Po fractionation experiments indicated that all the Po fractions except for the highly resistant Po fraction decreased during incubation.Application of pig feces and cow feces could largely increase each fraction of Po in the soils.Immediately after application of organic manure into the soils a large part of labile and moderately labile Po from organic manure was transferred into moderately resistant Po,which might be due to the fact that Ca-or Mg-inositol P was precipitated into Fe-inositol P.However,the availability of Po from organic manure in the soils would increase again after incubation because of the transformation of moderately labile and resistant Po fractions into labile Po fractions.Addition of cellulose or Pi into the soils showed a good effect on increasing all the Po fractions except for the highly resistant Po,and this effect was much more pronounced when cellulose was applied in combination with Pi.Therefore,in view of the effect of organic manure on improving P nutrition to plant,attention should be paid to both the Po and the organic substances from organic manure,It is suggested that application of Pi fertilizer combined with organic manure may be referred to as an effective means of protecting Pi from chemical fixation in soil.展开更多
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under st...This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.展开更多
The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of dra...The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry weight.Results indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by nanoclay.In addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.展开更多
Soil and water conservation is essential for sustaining food production and for preserving the environment in arid and semi arid lands (ASALs) where conditions for agriculture and other land use systems are often ha...Soil and water conservation is essential for sustaining food production and for preserving the environment in arid and semi arid lands (ASALs) where conditions for agriculture and other land use systems are often harsh and unpredictable. The ASALs of Algeria are an important source of a variety of non wood forest products like Stipa tenacissima L. plant (esparto grass). This research was conducted to determine the effects of different low concentration (〈 I%) polyacrylaJnide, Stipa tenacissima L. fiber (esparto grass fibers) and its mixtures with the polymer at water retention in arid and semi arid soil. All samples are characterized by infrared spectroscopy, X-ray Diffractometry, thermal analysis TG DSC and scanning electron micrographs (SEM). The results showed that polymer blend in soil could improve better soil physical proprieties decreased evaporation and increase water retention in arid soils compared with application of any other blend at the same concentration. The use of Polyacrylamide-Cellulose blend appears to promise for reducing the labor cost of irrigation at arid and semi-arid soils, and offers safe and environmentally friendly inexpensive materials. The importance of Polyacrylamide-Cellulose blends to alleviate poor physical properties and retain water in these arid regions to sustain plant growth.展开更多
基金Supported by Shanxi Province Soft Science Research Program(2014041020-2)~~
文摘[Objective] The aim was to detect effects of biochar on soil enzyme activity and mechanism. [Method] Soils were sampled from experimental fields of Shanxi Academy of Agricultural Sciences and added with charcoals in different types in order to analyze dynamic changes of alkaline phosphatase and cellulase activities and effects of charcoals on soil enzyme activities. [Result] By applying charcoal, enzyme activity of soil samples all improved and the increase degree was higher of alkaline phosphatase than cellulase activity. Mid-temperature charcoal at 8% is the best. [Conclusion] The research provides references for effects of biochar on physi- cal and chemical properties.
基金Project supported by the National Natural Science Foundation of China.
文摘The transformation of organic P(Po) from organic manures in two types of soils (ultisol and entisol) and the influences of external addition of organic substance or inorganic P(Pi) on Po under the condition of the 60% maximum water capacity were investigated.The results obtained from Po fractionation experiments indicated that all the Po fractions except for the highly resistant Po fraction decreased during incubation.Application of pig feces and cow feces could largely increase each fraction of Po in the soils.Immediately after application of organic manure into the soils a large part of labile and moderately labile Po from organic manure was transferred into moderately resistant Po,which might be due to the fact that Ca-or Mg-inositol P was precipitated into Fe-inositol P.However,the availability of Po from organic manure in the soils would increase again after incubation because of the transformation of moderately labile and resistant Po fractions into labile Po fractions.Addition of cellulose or Pi into the soils showed a good effect on increasing all the Po fractions except for the highly resistant Po,and this effect was much more pronounced when cellulose was applied in combination with Pi.Therefore,in view of the effect of organic manure on improving P nutrition to plant,attention should be paid to both the Po and the organic substances from organic manure,It is suggested that application of Pi fertilizer combined with organic manure may be referred to as an effective means of protecting Pi from chemical fixation in soil.
文摘This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency (45% and 36% respectively), as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.
文摘The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry weight.Results indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by nanoclay.In addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.
文摘Soil and water conservation is essential for sustaining food production and for preserving the environment in arid and semi arid lands (ASALs) where conditions for agriculture and other land use systems are often harsh and unpredictable. The ASALs of Algeria are an important source of a variety of non wood forest products like Stipa tenacissima L. plant (esparto grass). This research was conducted to determine the effects of different low concentration (〈 I%) polyacrylaJnide, Stipa tenacissima L. fiber (esparto grass fibers) and its mixtures with the polymer at water retention in arid and semi arid soil. All samples are characterized by infrared spectroscopy, X-ray Diffractometry, thermal analysis TG DSC and scanning electron micrographs (SEM). The results showed that polymer blend in soil could improve better soil physical proprieties decreased evaporation and increase water retention in arid soils compared with application of any other blend at the same concentration. The use of Polyacrylamide-Cellulose blend appears to promise for reducing the labor cost of irrigation at arid and semi-arid soils, and offers safe and environmentally friendly inexpensive materials. The importance of Polyacrylamide-Cellulose blends to alleviate poor physical properties and retain water in these arid regions to sustain plant growth.