Improvement of natural microbial remediation of petroleum-polluted soil using graminaceous plants

2009 ◽  
Vol 59 (5) ◽  
pp. 1025-1035 ◽  
Author(s):  
Z. Z. Zhang ◽  
S. M. Su ◽  
Y. J. Luo ◽  
M. Lu
Keyword(s):  
Soil Moisture ◽  
Carbon Content ◽  
Dehydrogenase Activity ◽  
Catalase Activity ◽  
Plant Roots ◽  
Natural Soil ◽  
Unplanted Soil ◽  
Degradation Rates ◽  
Graminaceous Plants ◽  
Rhizosphere Environment

A 150-day pot experiment was conducted with graminaceous plants grown in natural soil contaminated with petroleum. The relationships among microbial activity, dehydrogenase activity, catalase activity, soil moisture, and the petroleum degradation rate were analyzed. All three plants accelerated the degradation of petroleum compared with unplanted soil. Plant roots improved the soil moisture by about 5% (from 15% in unplanted soil to 20% in soil containing plant roots), and the number of microorganisms in the rhizosphere increased by more than three orders of magnitude. The induction of the rhizosphere environment and the intimidation of the petroleum changed the abundance and activity of the microorganisms. Dehydrogenase activity in the rhizosphere was 1.54 to 1.87 times the value in the unplanted soil, but catalase activity was 0.90 to 0.93 times the value in unplanted soil. The petroleum degradation rates in the rhizosphere were 2.33 to 3.19 times higher than in the unplanted soil. The effect of rhizosphere degradation clearly changed the hydrocarbon composition, increasing the degradation of alkane hydrocarbons with low and moderate carbon contents. The rhizosphere environment promoted degradation of the high-carbon-content hydrocarbons into low-carbon-content hydrocarbons. At the same time, the Pr/nC17, Ph/nC18, and Pr/Ph values increased by 0.99 and 2.69 units, and decreased by 1.25 units, respectively, compared with the undegraded oil. The plants also accelerated the isomerization of alkane hydrocarbons.

scholarly journals Dehydrogenase activity in topsoil at windthrow plots in Tatra National Park

2017 ◽  
Vol 63 (2-3) ◽  
pp. 91-96 ◽  
Author(s):  
Peter Hanajík ◽  
Jana Gáfriková ◽  
Milan Zvarík
Keyword(s):  
Microbial Biomass ◽  
Carbon Content ◽  
Dehydrogenase Activity ◽  
National Park ◽  
Dry Weight ◽  
Soil Samples ◽  
Control Plot ◽  
Microbial Biomass C ◽  
Wood Debris ◽  
Tatra National Park

AbstractThe aim of the study was to compare the effect of windthrow treatments established after the windstorm in 2004 on the activity of enzyme dehydrogenase (DHA) in forest topsoils. We also focused on the effect of the recent windthrow (May 2014) on the DHA in topsoil. Soil samples were collected in July 2014 from four sites in the Tatra National Park: EXT - tree trunks and wood debris extracted after the windstorm in 2004, NEX - area left for self-regeneration after the windstorm in 2004, REX - tree trunks and wood debris extracted after the windstorm (May 2014), REN - Norway spruce stand set as a control plot. We measured pH, dry weight %, soil organic matter (SOM), carbon content in microbial biomass (Cblo) and DHA. Dehydrogenase activity at studied plots was the lowest at the EXT plot and the highest values were measured at the REN plot. DHA at NEX was similar to REN suggesting comparable ecological conditions at these plots comparing to EXT. Carbon content in microbial biomass at plots reflected intensity of dehydrogenase activity in sequence EXT < REX < NEX < REN.

scholarly journals MISIRoot: A Robotic Minimum Invasion in Situ Imaging System for Plant Root Phenotyping

2020 ◽  
Author(s):  
Zhihang Song ◽  
Wei Qiu ◽  
Jian Jin
Keyword(s):  
Plant Protection ◽  
Plant Root ◽  
Low Cost ◽  
3D Structure ◽  
Color Images ◽  
Plant Roots ◽  
Natural Soil ◽  
Wide Range ◽  
Root Phenotyping

Abstract Background: Plant root phenotyping technologies play an important role in breeding, plant protection, and other plant science research projects. The root phenotyping customers urgently need technologies that are low-cost, in situ, non-destructive to the roots, and suitable for the natural soil environment. Many recently developed root phenotyping methods such as minirhizotron, X-CT, and MRI scanners have their unique advantages in observing plant roots, but they also have disadvantages and cannot meet all the critical requirements simultaneously. Results: The study in this paper focuses on the development of a new plant root phenotyping robot that is minimally invasive to plants and working in situ inside natural soil, called “MISIRoot”. The MISIRoot system mainly consists of an industrial-level robotic arm, a mini-size camera with lighting set, a plant pot holding platform, and the image processing software for root recognition and feature extraction. MISIRoot can take high-resolution color images of the roots in soil with minimal disturbance to the root and reconstruct the plant roots’ three-dimensional (3D) structure at an accuracy of 0.1 mm. In a test assay, well-watered and drought-stressed groups of corn plants were measured by MISIRoot at V3, V4, and V5 stages. The system successfully acquired the RGB color images of the roots and extracted the 3D points cloud data containing the locations of the detected roots. The plants measured by MISIRoot and plants not measured (control) were carefully compared with the results from the Hyperspectral Imaging Facility (reference). No significant differences were found between the two groups of plants at different growth stages. Conclusion: The MISIRoot system recently developed at Purdue University has been proved effective in root phenotyping with multiple advantages: With a comparatively low cost and minimal invasion to the plant, this system can automatically measure the root’s 3D structure and take color images of the roots in ordinary soil media, and in situ. This system provides a new option for root phenotyping researchers and has a potential to be applied in a wide range of research topics such as breeding, plant protection and so on.

Reducing gravity data for the influence of water storage variations beneath observatory buildings

Geophysics ◽  
2019 ◽  
Vol 84 (1) ◽  
pp. EN15-EN31 ◽  
Author(s):  
Marvin Reich ◽  
Michal Mikolaj ◽  
Theresa Blume ◽  
Andreas Güntner
Keyword(s):  
Soil Moisture ◽  
Gravity Data ◽  
Near Field ◽  
Water Storage ◽  
Natural Soil ◽  
Mass Distributions ◽  
Site Characteristics ◽  
Influence Of Water ◽  
Building Effects ◽  
Local Water

Ground-based gravimetry is increasingly used to study mass distributions and mass transport below the earth surface. The gravity effect of local water storage variations can be large and should be accounted for in the interpretation of these data. However, the effect of hydrologic mass changes in the immediate vicinity of the gravimeter is not considered in standard routines for separating unwanted signal components. This applies in particular to the effect of the buildings in which gravimeters are installed. The building shields the underlying soil from precipitation and evapotranspiration and thus directly affects the water storage dynamics in the near-field of the gravimeter. A combined approach of in situ soil moisture observations and hydrologic modeling was used to quantify the altered water storage variations below observatory buildings. Subsequently, the errors caused by different estimation approaches for this umbrella effect in hydrogravitational computations were assessed. Depending on the site characteristics, the errors range from 4.1 to [Formula: see text] for the intra-annual amplitude when natural soil moisture data are considered for modeling the umbrella effect, and they range from 4.1 to [Formula: see text] when assuming no gravity change within 5 m below the building. These results were condensed to general recommendations, leading to a new simple and broadly applicable method to reduce observed gravity data for building effects, given basic information about the gravimeter location, building dimensions, climatic regime, and soil type of the observation site. This new reduction approach indicates errors of the intra-annual amplitude from 1.9 to [Formula: see text].

Methodological approaches to evaluate dehydrogenase activity as a good indicator of soil functionality.

2021 ◽  
Author(s):  
Juan Antonio Campos ◽  
Carmen Moreno ◽  
Jaime Villena ◽  
Jesús D. Peco ◽  
Eva M. García-Noguero ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Linear Function ◽  
Dehydrogenase Activity ◽  
Incubation Time ◽  
Reduced Form ◽  
Tetrazolium Salt ◽  
Microorganism Population ◽  
Red Color ◽  
Soil Functionality ◽  
Degree Of Extraction

&lt;p&gt;Dehydrogenase activity (DHA) has been widely used as a good indicator to assess the oxidative status in soils. The common method determination relies on the reduction of an artificial electron receptor by the soil microorganisms, namely, a soluble tetrazolium salt that acquires a red color in its reduced form (formazan), being this way easily measured by colorimetry, after extraction by a proper solvent. This activity is very sensitive to all the factors that can reach the upper layer of soils, especially temperature and moisture, and its use has become very useful to determine the degree of xenobiotics toxicity or the goodness, or not, of agricultural procedures and management. To establish an appropriate methodology for the measurement and monitoring of this activity, in our work we evaluate the most relevant aspects that must be taken into account so that the determination of this activity is as consistent as possible.&lt;/p&gt;&lt;p&gt;Incubation time and pre-incubation: The incubation time appears as the main source of trouble in the interpretation of results. Most of the time, an incubation time of 24 hours is used, but some authors recommend shorter incubation periods to make the measurements at an initial rate and that way use a linear function. For this reason, some authors advise shorter periods of incubation after having a pre-incubation time with glucose or yeast extract. This way the reducing potential of the soil will be better represented.&lt;/p&gt;&lt;p&gt;Soil moisture: &amp;#160;For the DHA results of a certain area to be comparable, the degree of soil humidity has to be necessarily standardized since any change in soil moisture will lead to changes in DHA. Dry soils give figures of DHA close to zero. Precise readings of DHA can only be obtained minimizing the moisture interactions. A pre-incubation of 10 days with the soil hydrated with 50% of the water holding capacity, not only ensures equal moisture for all the samples but also serves to reactivate the soil microorganism population. After that, samples should be immediately incubated with the electron receptor and analyzed.&lt;/p&gt;&lt;p&gt;Formazan extraction: Special physicochemical properties of soils can lead to better or worse extraction of formazan. Some authors advise carrying out a simple trial to establish the degree of extraction of the formazan according to the slope of a linear function between the added formazan and that extracted.&lt;/p&gt;&lt;p&gt;Optimal TTC concentration: Some toxicity of TTC has been raised recently. Although the concentration of the substrate must be sufficient to saturate all the enzymatic capacity, it is advisable not to add an excess of TTC. The quantity and quality of organic matter may be behind the degree of severity of the toxic effect of TTC.&lt;/p&gt;

EVAPORATION FROM BARE SOIL COMPARED WITH EVAPOTRANSPIRATION FROM A POTATO CROP

1966 ◽  
Vol 46 (2) ◽  
pp. 199-204 ◽  
Author(s):  
J. M. Fulton
Keyword(s):  
Soil Moisture ◽  
Potato Crop ◽  
Growing Season ◽  
Bare Soil ◽  
Plant Roots ◽  
Moisture Loss ◽  
Root Penetration ◽  
Short Period ◽  
Summer Fallow ◽  
Bare Surface

Floating lysimeters were used to measure evaporation from bare soil and evapotranspiration from a potato crop during three consecutive seasons. Evaporation from bare soil amounted to 87.5% of the water lost by evapotranspiration from the crop. Moisture loss from the bare and cropped areas differed only for a short period of time at mid-season. It was concluded that, during this period, plant roots utilized moisture stored at depths beyond which water was available for evaporation. Later in the season when this source of water was exhausted losses from the two areas were again equal. Moisture conservation by summer-fallow was limited to that amount which was stored at a depth penetrated by plant roots but unavailable to evaporation from the bare surface. The amount of water conserved in these experiments was small but probably dependent upon the moisture characteristics of the soil, the depth of root penetration, and the frequency with which the soil moisture reservoir was recharged during the growing season.

EFFECTS OF 2,4-D AND SOIL MOISTURE ON THE CATALASE ACTIVITY, RESPIRATION, AND PROTEIN CONTENT OF BEAN PLANTS

1950 ◽  
Vol 28c (4) ◽  
pp. 393-405 ◽  
Author(s):  
W. G. Corns
Keyword(s):  
Carbon Dioxide ◽  
Soil Moisture ◽  
Protein Content ◽  
Catalase Activity ◽  
Visual Response ◽  
Moist Soil ◽  
Moisture Concentration ◽  
Carbon Dioxide Output ◽  
Bean Plants ◽  
Moisture Conditions

Bean plants grown under various controlled moisture conditions in a greenhouse, and sprayed with 2,4-D, showed differences in catalase activity, carbon dioxide output, total nitrogen content, and visual response. Catalase and respiration of leaves were stimulated or depressed depending upon soil moisture, concentration of 2,4-D, and time after treatment, but there was not always a positive correlation between the two activities. Protein in leaves, with a few noteworthy exceptions, was decreased by 2,4-D. Extremes among leaf responses were induced in plants recently deprived of optimum moisture. Catalase, respiration, and protein content of stems were greatly increased by 2,4-D. This was especially noticeable in plants in moist soil. Soil treatments with 2,4-D solution followed by adequate moisture effected, in above-ground parts of plants, responses resembling those measured after foliage sprays on beans in moist soil. Fasciation of underground parts resulted only from a soil application involving relatively dilute (50 p.p.m.) concentration of 2,4-D.

Sign in / Sign up

Export Citation Format

Share Document