scholarly journals Assessment of Microbial Biomass Carbon and Nitrogen in Some Tea Soils of Bangladesh

1970 ◽  
Vol 25 (1) ◽  
pp. 21-25
Author(s):  
SM Abdur Rahman ◽  
ARM Solaiman

Microbial biomass carbon (C) and nitrogen (N) and their contribution to soil organic carbon and total N contents were assessed in soils collected from Bilashchara Tea Estate under Bangladesh Tea Research Institute (BTRI), Srimangal of Moulavibazar district, and Sripur Tea Garden under Jaintapur of Sylhet district. Microbial biomass C and N in Bila shchara Tea Estate soils varied from 90.4-144.0 and 20.5-29.0 mg/kg soil, and that of Sripur Tea Garden soils varied from 120.7-362.0 and 26.6-59.5 mg/kg soil, respectively. Within the two tea growing areas biomass C/N ratios ranged from 3.35-6.12. Relationships between biomass C and organic carbon and biomass N and total N were positively correlated. The contribution of biomass C to soil organic C was 1.23%, ranging from 0.9-1.55% and the contribution of biomass N to total N content of the soils ranged from 1.19-2.89%. Keywords: Biomass carbon (C); Biomass nitrogen (N); Organic C; Total N; Tea soilDOI: http://dx.doi.org/10.3329/bjm.v25i1.4850 Bangladesh J Microbiol, Volume 25, Number 1, June 2008, pp 21-25

1999 ◽  
Vol 79 (1) ◽  
pp. 73-84 ◽  
Author(s):  
C. A. Campbell ◽  
V. O. Biederbeck ◽  
G. Wen ◽  
R. P. Zentner ◽  
J. Schoenau ◽  
...  

Measurements of seasonal changes in soil biochemical attributes can provide valuable information on how crop management and weather variables influence soil quality. We sampled soil from the 0- to 7.5-cm depth of two long-term crop rotations [continuous wheat (Cont W) and both phases of fallow-wheat (F–W)] at Swift Current, Saskatchewan, from early May to mid-October, 11 times in 1995 and 9 times in 1996. The soil is a silt loam, Orthic Brown Chernozem with pH 6.0, in dilute CaCl2. We monitored changes in organic C (OC) and total N (TN), microbial biomass C (MBC), light fraction C and N (LFC and LFN), mineralizable C (Cmin) and N (Nmin), and water-soluble organic C (WSOC). All biochemical attributes, except MBC, showed higher values for Cont W than for F–W, reflecting the historically higher crop residue inputs, less frequent tillage, and drier conditions of Cont W. Based on the seasonal mean values for 1996, we concluded that, after 29 yr, F–W has degraded soil organic C and total N by about 15% compared to Cont W. In the same period it has degraded the labile attributes, except MBC, much more. For example, WSOC is degraded by 22%, Cmin and Nmin by 45% and LFC and LFN by 60–75%. Organic C and TN were constant during the season because one year's C and N inputs are small compared to the total soil C or N. All the labile attributes varied markedly throughout the seasons. We explained most of the seasonal variability in soil biochemical attributes in terms of C and N inputs from crop residues and rhizodeposition, and the influences of soil moisture, precipitation and temperature. Using multiple regression, we related the biochemical attributes to soil moisture and the weather variables, accounting for 20% of the variability in MBC, 27% of that of Nmin, 29% for LFC, 52% for Cmin, and 66% for WSOC. In all cases the biochemical attributes were negatively related to precipitation, soil moisture, temperature and their interactions. We interpreted this to mean that conditions favouring decomposition of organic matter in situ result in decreases in these attributes when they are measured subsequently under laboratory conditions. We concluded that when assessing changes in OC or TN over years, measurements can be made at any time during a year. However, if assessing changes in the labile soil attributes, several measurements should be made during a season or, measurements be made near the same time each year. Key words: Microbial biomass, carbon, nitrogen, mineralization, water-soluble-C, light fraction, weather variables


Soil Research ◽  
1987 ◽  
Vol 25 (4) ◽  
pp. 461 ◽  
Author(s):  
RC Dalal ◽  
RJ Mayer

The dynamics of nitrogen mineralization potential (N0) and mineralization rate constant (k) were studied in six major soils which had been used for cereal cropping for up to 20-70 years. In the top 0.1 m layer of virgin soils, N0 varied from 110 � 22 mg kg-1 soil (Riverview) to 217 � 55 mg kg-1 soil (Langlands-Logie), representing about 13% and 11%, respectively, of total N in these soils. Upon cultivation and cropping, N0 declined by 1 7 � 0.5 mg kg-1 yr-1 (Riverview) to 4.8 � 2.0 mg kg -1 yr -1 (Billa Billa). This represented < 20% of total N lost annually from the top layer (0-0.1 m depth) of these soils. The k values varied less than the N0 values, both within and among soils, and were also less affected by cultivation than N0. The mineralizable N in cultivated soil during cropping for periods up to 70 years can be estimated from N0 and k values, taking No as 5% of total N for soils of <40% clay and 15% of total N for soils of >40% clay and k as 0.066 week-1 at 40�C (0.027 week-1 and 0.054 week-1 at 25�C and 35�C, respectively). Organic C and N contained in the 'stabilized' microbial biomass (determined after 30 weeks' pre-incubation) accounted for 1.7-38% of total organic C and 2.0-5.1% of total N in the six soils studied. The microbial biomass C and N declined with cultivation in most soils, biomass N representing 10-23% of the total annual loss of N0. The microbial biomass, urease activity and total N, in addition to a number of other soil properties [e.g. light-fraction (<2 Mg m-3) C, sand-size C, CEC and ESP], were significantly correlated with N0 and k, thus indicating the existence of a myriad of environments for the activity, association and stability of microbial biomass and potentially mineralizable N in soil.


2008 ◽  
Vol 54 (No. 5) ◽  
pp. 212-218 ◽  
Author(s):  
J. Černý ◽  
J. Balík ◽  
M. Kulhánek ◽  
V. Nedvěd

Microbial biomass nitrogen and carbon were studied in long-term field experiments with continuous cultivation of silage maize and with crop rotation. A positive effect of organic fertilizers on the microbial biomass nitrogen and the carbon content in soil was observed. Statistically significant effect of organic fertilizers on the higher content of microbial biomass C and N was established in the first year after their application. During the application the content of microbial biomass carbon and nitrogen decreased, but there were higher biomass C and N contents compared to control, even without statistical significance. A negative effect on microbial biomass carbon and nitrogen content in soil came from the application of mineral nitrogen fertilizers in experiments with maize. Statistically significant effect of mineral N fertilizers was observed after their application. In the course of the N fertilizers application the content of microbial biomass carbon and nitrogen was lower than control. No statistically significant effects of mineral nitrogen fertilizers on the microbial biomass nitrogen and carbon content were observed in field experiments with crop rotation over the eight years of experiment duration. The higher effect of mineral and organic fertilizers application on the changes in microbial biomass C and N was reported in experiments with continuous cultivation of maize compared to experiments with crop rotation.


Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 508 ◽  
Author(s):  
Zhiwei Ge ◽  
Shuiyuan Fang ◽  
Han Chen ◽  
Rongwei Zhu ◽  
Sili Peng ◽  
...  

Soil resident water-stable macroaggregates (diameter (Ø) > 0.25 mm) play a critical role in organic carbon conservation and fertility. However, limited studies have investigated the direct effects of stand development on soil aggregation and its associated mechanisms. Here, we examined the dynamics of soil organic carbon, water-stable macroaggregates, litterfall production, fine-root (Ø < 1 mm) biomass, and soil microbial biomass carbon with stand development in poplar plantations (Populus deltoides L. ‘35’) in Eastern Coastal China, using an age sequence (i.e., five, nine, and 16 years since plantation establishment). We found that the quantity of water-stable macroaggregates and organic carbon content in topsoil (0–10 cm depth) increased significantly with stand age. With increasing stand age, annual aboveground litterfall production did not differ, while fine-root biomass sampled in June, August, and October increased. Further, microbial biomass carbon in the soil increased in June but decreased when sampled in October. Ridge regression analysis revealed that the weighted percentage of small (0.25 mm ≤ Ø < 2 mm) increased with soil microbial biomass carbon, while that of large aggregates (Ø ≥ 2 mm) increased with fine-root biomass as well as microbial biomass carbon. Our results reveal that soil microbial biomass carbon plays a critical role in the formation of both small and large aggregates, while fine roots enhance the formation of large aggregates.


2009 ◽  
Vol 6 (4) ◽  
pp. 6749-6780 ◽  
Author(s):  
R. Guicharnaud ◽  
O. Arnalds ◽  
G. I. Paton

Abstract. Temperature change is acknowledged to have a significance effect on soil biological processes and the corresponding sequestration of carbon and the cycling of key nutrients. Soils at high latitudes are likely to be particularly impacted by increases in temperature. In this study, the response of a range of soil microbial parameters (respiration, nutrient availability, microbial biomass carbon, arylphosphatase and dehydrogenase activity) to temperature changes was measured in sub-arctic soils collected from across Iceland. Sample sites reflected two soil temperature regimes (cryic and frigid) and two land uses (pasture and arable). The soils were sampled from the field frozen, equilibrated at −20°C and then incubated for two weeks at −10°C, −2°C, +2°C and +10°C. Respiration and enzymatic activity were temperature dependent. Microbial biomass carbon and nitrogen mineralisation did not change with temperature. The main factor controlling soil respiration at −10°C was the concentration of dissolved organic carbon. At −10°C, dissolved organic carbon accounted for 88% of the fraction of labile carbon which was significantly greater than that recorded at +10°C when dissolved organic carbon accounted for as low as 42% of the labile carbon fraction. Heterotrophic microbial activity is governed by both substrate availability and the temperature and this has been described by the Q10 factor. Elevated temperatures in the short term may have little effect on the size of the microbial biomass but will have significant impacts on the release of carbon through respiration. These results demonstrate that gradual changes in temperature across large areas at higher latitudes will have considerable impacts in relation to global soil carbon dynamics.


2016 ◽  
Vol 46 (3) ◽  
pp. 284-291 ◽  
Author(s):  
Adriano Stephan Nascente ◽  
Anna Cristina Lanna

ABSTRACT The presence of cover crop straw and early application of total N at sowing may provide significant changes in the microbial population, reflecting on the N dynamics in the soil and in upland rice plants. This study aimed at determining the effect of the early application of nitrogen doses as mineral N and microbial biomass carbon in the soil, as well as in the activity of nitrate reductase, and grain yield of upland rice plants cultivated under no-tillage system (NTS). A randomized blocks design, in a split-plot scheme, with four replications, was used. The treatments consisted of N doses (0 kg ha-1, 40 kg ha-1, 80 kg ha-1 and 120 kg ha-1) and the presence or absence of U. brizantha cover straw. Maintaining the straw on the soil surface reduces the ammonium levels and increases the microbial biomass carbon content of the soil. The application of increasing doses of N in the soil provides increases in the levels of nitrate and ammonium in the soil up to 28 days after emergence. The activity of the nitrate reductase enzyme in the plants increases and the contents of ammonium and nitrate in the soil decrease with the crop development. The number of panicles and grain yield of upland rice increase with the increase of the nitrogen fertilization, but decrease in the presence of U. brizantha straw. Thus, it is recommend the use of early N fertilization in upland rice crop.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8531 ◽  
Author(s):  
Yulu Zhang ◽  
Dong Cui ◽  
Haijun Yang ◽  
Nijat Kasim

Background A wetland is a special ecosystem formed by the interaction of land and water. The moisture content variation will greatly affect the function and structure of the wetland internal system. Method In this paper, three kinds of wetlands with different flooding levels (Phragmites australis wetland (long-term flooding), Calamagrostis epigeios wetland(seasonal flooding) and Ditch millet wetland (rarely flooded)) in Ili Valley of Xinjiang China were selected as research areas. The changes of microbial biomass carbon, soil physical and chemical properties in wetlands were compared, and redundancy analysis was used to analyze the correlation between soil physical and chemical properties, microbial biomass carbon and enzyme activities (soil sucrase, catalase, amylase and urease). The differences of soil enzyme activities and its influencing factors under different flooding conditions in Ili Valley were studied and discussed. Result The results of this study were the following: (1) The activities of sucrase and amylase in rarely flooded wetlands and seasonally flooded wetlands were significantly higher than those in long-term flooded wetlands; the difference of catalase activity in seasonal flooded wetland was significant and the highest. (2) Redundancy analysis showed that soil organic carbon, dissolved organic carbon, total phosphorus and soil microbial biomass carbon had significant effects on soil enzyme activity (p < 0.05). (3) The correlation between soil organic carbon and the sucrase activity, total phosphorus and the catalase activity was the strongest; while soil organic carbon has a significant positive correlation with invertase, urease and amylase activity, with a slight influence on catalase activity. The results of this study showed that the content of organic carbon, total phosphorus and other soil fertility factors in the soil would be increased and the enzyme activity would be enhanced if the flooding degree was changed properly.


2018 ◽  
Vol 2 ◽  
pp. 96-101
Author(s):  
Dil Kumar Limbu ◽  
Madan Koirala

The soil microbial biomass carbon to soil organic carbon ratio is a useful measure to monitor soil organic matter and serves as a sensitive index than soil organic carbon alone. Thus, the objective of this study is to identify and quantify the present status of ratio of soil microbial biomass carbon to soil organic carbon in Himalayan rangeland and to make recommendations for enhancing balance between microbial carbon and organic carbon of the soil. To meet the aforementioned objective, a field study was conducted from 2011 to 2013 following the Walkley-Black, Chromic acid wet oxidation method, and chloroform fumigation method for analysis of microbial carbon and organic carbon respectively. The study showed that the heavily grazed plot had significantly less value of ratio than occasionally grazed and ungrazed plots. The ratio was significantly high on legume seeding plot compared to nonlegume plot, but the ratio was independent of soil depth. Soil microbial biomass appeared to be more responsive than soil organic matter.


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