Top PDF Total and labile organic carbon content in agroecological system

Total and labile organic carbon content in agroecological system

Total and labile organic carbon content in agroecological system

RESUMO: Em sistema de consórcio alface-cenoura submetido a doses crescentes de composto orgânico (0, 12, 24, 48 Mg ha -1 ) foram monitorados o carbono da biomassa microbiana do solo (CBM), carbono lábil de solo fumigado (CLF), não fumigado (CLNF), solo autoclavado (CLA) e carbono orgânico total (COT) na profundidade de 0-10 cm. Solo de pastagem e floresta adjacentes ao experimento foram usados como referência. Amostras de solo foram coletadas aos 8 dias antes da instalação, 0, 6, 60 e 114 dias após adubação. O CLF foi quem apresentou correlação mais consistente com o COT, atributo mais utilizado para detectar mudanças no conteúdo de matéria orgânica do solo. O aumento das doses de composto orgânico aumentou o conteúdo de CBM, CLF, CLNF, CLA e COT. A partir dos 60 dias após plantio, CBM e CLF apresentaram redução de seus níveis em função da qualidade do composto orgânico. Os solos de pastagem e floresta comportaram-se como contrastes, contendo menor e maior conteúdo de carbono do solo, respectivamente.
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Labile forms of carbon and soil aggregates

Labile forms of carbon and soil aggregates

Soil organic matter (SOM) plays an important role in the soil aggregation and vice versa, its incorporation into the soil aggregates is one of the mechanisms of soil organic carbon stabilization. In this study the influence of labile carbon fractions on the fractions of dry-sieved (DSA) and wet-sieved (WSA) macro-aggregates and the relationship between the content of total organic carbon (TOC) and its labile fractions in the soil and in the fractions of macro-aggregates were determined. The experiment included six soil types (Eutric Fluvisol, Mol- lic Fluvisol, Haplic Chernozem, Haplic Luvisol, Eutric Cambisol, Rendzic Leptosol) in four ecosystems (forest, meadow, urban, and agro-ecosystem). In the case of DSA, the contents of labile fractions of carbon, in par- ticular cold water extractable organic carbon (CWEOC) and hot water extractable organic carbon (HWEOC), had a higher impact on the proportions of larger fractions of macro-aggregates (3–7 mm), while in the case of WSA, the impact of labile fractions of carbon, mainly labile carbon (C L ) oxidizable with KMnO 4 , was higher on the proportions of smaller fractions of aggregates (0.25–1 mm). The WSA size fraction of 0.5–1 mm seems an important indicator of changes in the ecosystems and its amounts were in a negative correlation with C L (r = –0.317; P < 0.05) and HWEOC (r = –0.356; P < 0.05). In the WSA and DSA size fractions 0.5–1 mm, the highest variability in the contents of TOC and C L was recorded in the forest ecosystem > meadow ecosystem > urban ecosystem > agro-ecosystem. The higher were the inputs of organic substances into the soil, the greater was the variability in their incorporation into the soil aggregates. The influence of the content of TOC and its labile forms on their contents in the DSA and WSA was different, and the contents of TOC and C L in the ag- gregates were more significantly affected by the C L content than by water soluble carbon. In the case of WSA fractions, their carbon content was more affected in the 1–2 mm than in 0.5–1 mm fraction.
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Comparison of the effect of various long-term fertilization systems on the content and fractional composition of humic compounds in Lessive soil

Comparison of the effect of various long-term fertilization systems on the content and fractional composition of humic compounds in Lessive soil

Abstract: A field experiment was established in 1972 on Luvisol. Three types of fertilizers – cattle manure (CM), cattle slurry (CS) and mineral fertilizers were used. CS was applied in the following doses: I – balanced with CM in terms of the amount of introduced total nitrogen and II – balanced with CM in terms of the amount of introduced total organic carbon (C tot ). 39 years after the experiment was established, half of each experimental plot was limed and since then the experiment was carried in two series – non-limed and limed soils. The paper presents the results of soil analyses 41 years after the experiment was started. It was found that each fertilization system increased the C tot content in soil in relation to the unfertilized control plot. The increase of C tot fluctuated between 0.35–6.22 g/kg of dry matter. In both series, the highest C tot content was observed in the soil fertilized with CM and CM + PK. Limed compared to non-limed soil contained nearly 25% more carbon of humic acids than fulvic acids and nearly 20% lower content of low molecular humic bonds. Liming considerably widened the humic acids carbon:fulvic acids carbon (C HA :C FA ) ratio of the fertilized soils, up to 1.32–1.87, while the corresponding objects of the non-limed series showed the C HA :C FA ratio between 0.75–0.97.
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Nitrogen balance and mineral nitrogen content in the soil in a long experiment with maize under different systems of N fertilization

Nitrogen balance and mineral nitrogen content in the soil in a long experiment with maize under different systems of N fertilization

Besides yield and N uptake the basic goal of these ex- periments was to study nitrogen transformations in the soil. Table 5 shows total contents of carbon and nitro- gen in the topsoil after harvest in 2002. Data in this table document a statistically lower content of nitrogen for DAM treatment compared to the control. A decrease in carbon content is also obvious, but it is not statistically significant. A similar trend of a decrease in C t and N t con- tent was measured for AS treatment. These results are consistent with the conclusions drawn by Collins et al (1992), who reported that the applications of mineral ni- trogen fertilizers increased the mineralization of soil or- ganic matters. The widest C/N ratio was found for DAM treatment. The results of Kubát et al. (1999) are confirmed that nitrogenous compounds of soil organic matter are
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Humus Substances and Soil Aggregates in the Soils with Different Texture

Humus Substances and Soil Aggregates in the Soils with Different Texture

tions (clay, silt) are in a positive correlation with total organic carbon (TOC) and the coarse fractions (sand) in a negative (Burke et al. 1989; Bronson et al. 2004). A significant part of clay minerals is in the linkage with a large amount of organic substances (Jastrow 1996), which can be stabilized through the adsorption on the mineral surfaces (Baldock & Skjemstad 2000), bridges of polyvalent cations (Muneer & Oades 1989), binding into the interlayers of clay minerals (Kleber et al. 2007). The stabilization of SOM is mainly controlled by the organo-mineral association (Cai et al. 2016) and the iron-oxides and hydroxides. The content and quality of HS strongly influence the total and labile trace elements content in the soil (Karabcová et al. 2015) that can play the role of possible glue agents. HS are one of the most important fractions of SOM (Vergnoux et al. 2011), which may also through its functional groups enter into interactions with metal ions to form complexes. In terms of a long term stability of soil aggregates, their humified and hydrophobic components are mainly important (Sodhi et al. 2009). The objectives of this study were as follows: (i) to assess the influence of HS and their fractions in the soil on the proportions of carbon (TOC, la- bile, non-labile) in water-resistant macro-aggregates (WSA), (ii) to determine the differences between the amount of carbon in WSA in coarse-grained (CGS) and fine-grained (FGS) soils with dependence on the proportions of HS in the soil.
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Petrophysical evaluation of Total Organic Carbon Content (TOC) in Agbada Formation, Niger Delta Basin

Petrophysical evaluation of Total Organic Carbon Content (TOC) in Agbada Formation, Niger Delta Basin

The Niger Delta which is made up of one petroleum system; the Tertiary Niger Delta (Akata- Agbada) Petroleum System has been extensively studied with publications from authors including Short and Stauble (1967), Ekweozor and Daukoru (1984), Tuttle et al. (1999), and Nwajide (2013). Others include Doust and Omatsola (1990), Reijers et al. (1997), Evamy et al. (1978), Hack et al. (2000), Nwachukwu (1986), and Whiteman (1982). It is composed of three main lithologic units; the basal marine Akata Formation of Palaeocene-Recent age with dominantly thick dark grey shale and some sand or silt in the upper part. It is the main hydrocarbon source rock in the Niger Delta. The paralic Agbada Formation of Eocene to Pleistocene age overlies the Akata Formation and is composed of alternating sandstone, siltstone and shale, and forms the main reservoir rock in the Niger Delta petroleum system with hydrocarbons being produced from sandstone and unconsolidated sands. The Benin Formation of Oligocene age is the topmost and most shallow part of the deltaic clastic wedge overlying the Agbada Formation. It is made up of continental deposits with over 70% of sands.
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Dynamics of Organic Carbon and Nutrients after Organic Waste Addition in an Acid Soil

Dynamics of Organic Carbon and Nutrients after Organic Waste Addition in an Acid Soil

Total organic C, labile organic C and humic acid C in organic waste treatments were significantly higher than in the control (Table 5). The addition of organic waste increased total organic C, labile organic C and humic acid C by 15-40%, 54-92% and 39-63% respectively after 10 weeks of incubation. Total organic C showed a tendency to decrease with increasing incubation time (Fig. 2). After 2 weeks of incubation, the total organic C content ranged from 16.10 to 22.07 g/kg and decreased to 15.00 and 21.07 g/kg after 10 weeks of incubation (Table 5). Similar results were reported by several other researchers. Gulser et al. (2010) reported that the increase in organic soil C content occurred with the addition of tobacco waste and the organic C content decreased and was almost constant after 80 days of incubation. Serramia et al. (2013) also reported that organic matter application increased total organic C after 90 days of incubation and tended to decrease after 150 days of incubation. The decrease in the amount of soil organic C with increasing incubation time indicates the presence of an unstable organic C fraction that decomposes to CO 2 (Follett et al. 2007). Increased doses of organic waste addition showed a tendency to increase organic labile C content
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Investigating the Changes of Total Organic Carbon Content in Bottled Water Under Environmental Stress Conditions

Investigating the Changes of Total Organic Carbon Content in Bottled Water Under Environmental Stress Conditions

Consumption of bottled drinking water has increased considerably in the recent years (Zandvakili et al., 2005). This increasing trend is probably due to the consumers' perception of the good quality and safety of bottled waters (Ali Mohammadi, et al., 2013; Loloei, etc. 2009). The research on the quality assessment of bottled water has a long history and includes a variety of fields [1]. Polyethylene terephthalate (PET) bottles can affect the chemical properties of water inside the bottle over time [2]. These effects can include the migration of mineral or organic compounds as well [3]. Storage conditions can affect the severity of these changes [4]. Organic compounds released from these containers can result in the potential risk of poisonous contents for genes, negative effects on endocrine system and cancers [5]. Unfortunately, there has not been a proper study in this regard in Iran. Careful examination of the organic materials is a time consuming and costly process [6]. Instead of measuring the water in parts, the level of TOC changes
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Effect of Soil Management Practices on the Mineralization of Organic Matter and Quality of Sandy Soils

Effect of Soil Management Practices on the Mineralization of Organic Matter and Quality of Sandy Soils

assessment the susceptibility to chemical oxida- tion of SOC, the method with a solution of po- tassium permanganate VII was use [Łoginow et al. 1987]. The modification and standardization of this method [Blair et al. 1995, Lefroy 1993] allows determining the content of labile carbon (C L ) and non-labile carbon (C NL ) of SOM [Skjem- stad et al. 2006]. The content of C L can provide a considerable indicator of SOC transformations in soil [Conteh et al. 1999]. Considering the interac- tions between C org , C L and C NL , one can determine the following: Lability Index (LI), Carbon Pool Size Index (CPI) and Carbon Management Index (CMI) in soil. On the basis of those indices it is possible to evaluate the SOC management as a measure of relative permanence of various meth- ods of soil use. In the studies on SOC in cultivated soils, the obtained results are referred to the ref- erence objects. These are usually non-cultivated soils, forest soils, pastures [Blair et al. 1995, Blair et al. 1997, Szombathova 1999], as well as urban soils [Vaseneva et al. 2013]. Szombathova [1999] compared the forest soil with the soils under or- ganic and integrated farming using CMI, CPI, LI. She also demonstrated that the total organic carbon content in the forest soil was almost three- fold higher than in the arable soils and the val- ues of LI in the soil under organic farming were higher than in the forest soil. Strączyńska et al. [2009] showed that in the ectohumus under the plantings of black locust, the values of CPI and CMI are more favourable than under the trees of Scots pine. The soil studies of the static fertilisa- tion experiment exposed to long-term agrotechni- cal treatments showed the applicability of these indices to the evaluation of the effect of the type of fertilisation on the organic carbon management in soil [Cieścińska 2007a,b].
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Effect of organic fertilizers on soil organic carbon and risk trace elements content in soil under permanent grassland

Effect of organic fertilizers on soil organic carbon and risk trace elements content in soil under permanent grassland

The effect of different kinds of organic matter inputs on elemental composition, content, and quality of humic sub- stances was studied on permanent grassland during 2008–2013. The experiment included two organic fertilizer types – compost and slurry, both with the range of stocking rates 0.9, 1.4, and 2.0 livestock units (LU)/ha (corresponding to 54, 84, and 120 kg N/ha, respectively), and control without any fertilizer. The soil was sandy-loam, of Cambisol type, with semi natural permanent grassland. Labile forms and total contents of selected trace elements (Co, Cu, Zn, Cd) and macroelements (Ca, Mg, K, P, and N) were measured. Soil organic matter parameters such as total organic carbon (C ox ), humic substances (HS), humic acid (HA), fluvic acid (FA), and labile carbon forms (hot-water extractable carbon (C hws ), cold water extractable carbon (C cws )) were determined. Results showed that the greatest content of P, Ca, Mg, and N in the soil was detected by the CO 2.0 treatment. Furthermore, the positive effect of compost on C ox , C hws , HA, FA, HS, N and macronutrients was observed. The elemental analysis of humic acids showed lower carbon content and higher oxygen content in HA molecule, which indicated young humic acids, with a lower condensation degree. The content and quality of humic substances strongly influenced the total and labile trace elements content in the soil. Additionally, hot water soluble carbon significantly correlated with plant available forms of Zn, Cu, and Cd. Keywords: compost; labile organic carbon; slurry; trace elements
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Effects of Oxygen Diffusion on Physicochemical Characteristics of Petroleum Contaminated Sandy Loam Soil

Effects of Oxygen Diffusion on Physicochemical Characteristics of Petroleum Contaminated Sandy Loam Soil

They indicated that the concentrations of the carbon atoms decreased with time.The peak of each of the carbon components also decreased with Time. The decrease in concentration of Total Petroleum Hydrocarbon in the soils showed that, the indigenous bacterial in the impacted soils have the ability to degrade petroleum hydrocarbon since they could use it as source of carbon and energy (Obiakalaijeet al., 2015).The reductions in percentage of hydrocarbon concentration in Sandy loam soils were obtained as 17%, 55% and 75% for soils in reactor A, B and C respectively. The highest percentage degradation of Total Petroleum Hydrocarbon noticed in soils in reactor C may be attributed to an increase in population of microorganism because of availability of sufficient oxygen concentration in the soils at 100cm depth as a result of oxygen diffusion, therebyutilizingthe hydrocarbons as source of energy by the Microorganism.
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The organic matter abundance evaluation of Shuangyang group in Chaluhe fault depression of Yitong basin

The organic matter abundance evaluation of Shuangyang group in Chaluhe fault depression of Yitong basin

As is shown in figure 4, on the whole, each layer of the residual organic carbon of shuangyang group in xinanpu sag reached a good level and the abundance of organic matter is high. Figure 5 is the diagram of the frequency distribution in Botai sag, it shows that the organic matter abundance of shuang1 segment and shuang2 segment in shuangyang group 55% reached a good level, shuang3 segment 85% reached a good level. The organic matter abundance of xinanpu sag is a little higher than it in botai sag. Among them, shuang3 segment achieves a good standard, other sections reach for medium – good level.
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Effect of neutralising substances on reducing the influence of cobalt on the content
of selected elements in soil

Effect of neutralising substances on reducing the influence of cobalt on the content of selected elements in soil

vector variables affected by cobalt and neutralising sub- stances (manure, clay, charcoal, zeolite and calcium oxide). The value of vectors denoting the available phosphorus, magnesium and potassium in soil was nearly 37% of the total correlation of the data set; furthermore, the value of total nitrogen, organic carbon and the C:N ratio in soil was nearly 42%. The vector which illustrates the content of magnesium and organic carbon was shorter than the other vectors, so it can be concluded that they contributed little to the variability studied. The PCA illustrates a highly signifi- cant correlation between the vectors denoting the available phosphorus and magnesium, as well as organic carbon and the C:N ratio in soil (Fig. 1). A significant (but much weaker) correlation was observed between the available phosphorus and magnesium, and the available potassium. However, a negative correlation was observed between total nitrogen and organic carbon, and the C:N ratio. No
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Long-term Impacts of Silvicultural Treatments on Soil Microbial Biomass, Community Composition, and N Mineralization

Long-term Impacts of Silvicultural Treatments on Soil Microbial Biomass, Community Composition, and N Mineralization

Kanhapludult). Average annual precipitation is 114 cm and average temperatures range from 2°C in January to 26°C in July. The study consisted of three experimental blocks, each with eight 42 m x 27 m plots established in a 2 x 2 x 2 factorial, randomized split-plot design. Each block had four main plots with the factorial combination of two levels of harvest utilization (stem only: only the bole of the tree was removed and limbs and leaf litter were left on site, and whole tree removal: the entire above-ground tree biomass was removed from the site), and two levels of site preparation (chop and burn (CH): a drum roller was used to break up large organic debris followed by a light burn of the site, and shear, pile and disk (DI): a blade was used to shear stumps, the organic material was pushed into windrows and the site disked to a depth of 7-12 cm). The chop and burn treatment resulted in the estimated removal of 46 kg N ha -1 and the shear, pile and disk treatment removed 591 kg N ha -1 (Tew et al., 1986). These two treatments were divided into two subplots and two levels of
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Carbon Sequestration Potential of Constructed Wetlands used for Wastewater Treatment

Carbon Sequestration Potential of Constructed Wetlands used for Wastewater Treatment

industrial campus. Further it was found that the constructed wetlands have a good capacity to maintain the organic stocks in its medium as well at the anchoring gravel medium and the floor. Present study focused on the ‘subsurface flow constructed wetlands’ that have a smaller water column around the anchoring gravel bed as compared to the natural systems. Hence they have a greater carbon sequestration potential when compared to the natural systems. Constructed wetlands are a wise option to treat industrial waste waters efficiently when compared to the energy intensive conventional (engineering-based) treatment plants. Moreover they not only help to develop green belt around the industry but also serve to absorb the atmospheric carbon in a beneficial manner. The present study focuses on the carbon sequestration potential of two constructed wetlands.
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Multi-scale analysis of carbon stocks and process indicators in the agro-ecosystem of Canterbury, New Zealand

Multi-scale analysis of carbon stocks and process indicators in the agro-ecosystem of Canterbury, New Zealand

ground. The future scenarios undertaken investigated the effect of various land cover and management combinations and their effect on forecasting soil carbon stock (2014-2024). The results showed a 10%, 6%, 34% decrease of soil carbon stocks in the alternative dairy, sheep and beef and arable scenarios. The main driver for decreases in soil carbon stock predictions was commonly irrigation and tilling intensity and supported by the literature (i.e., Dersch & Böhm, 2001; Kelliher et al., 2012; Moinet et al., 2017). These modelling results indicated a large discrepancy in projected soil carbon stocks between the default values used by the MfE model in contrast to the research informed scenarios (2014 - 2024). This result corroborated the notion that soil carbon stocks were driven by above-ground activities that occurred at the local scale (Chapter 3 and Chapter 4). A second key finding was the indication of how much shelterbelt area would be needed per decade to offset the predicted losses; estimates ranged between 1 ha and 50 ha per farm, representing up to 49% of the farmed land. Furthermore, this study had applied the MfE model approach to investigate the soil carbon capacity change across Canterbury over the past decade. The results highlighted very subtle changes, with a few localised areas of both strong increase and decrease inland resulting in no real change across the Canterbury plains regarding its soil carbon capacity over the past decade (2004 - 2014). This finding supported the notion that the majority and significant land use and cover changes in Canterbury might have happened before the decade investigated (Parfitt et al., 2008; Parfitt et al., 2006). Thus, this study has demonstrated the potential for the application of such models to soil carbon research in the agricultural farm environment.
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The Community Rating System: Assessing Indicators of Community Participation, A Dasymetric and Sovi Approach

The Community Rating System: Assessing Indicators of Community Participation, A Dasymetric and Sovi Approach

hydrocarbons, with variable amounts of carbon atoms depending on carbon source (Eglinton and Hamilton, 1967; Nott et al., 2000; Volkman et al., 1998). Terrestrial material from higher land plants typically produce alkanes that have longer chain lengths than aquatic microbes (Eglington and Hamilton, 1967). Therefore, by looking at the relative contribution of alkanes of different chain lengths, it can reveal info about the alkane carbon source. Additionally, the relative concentration of odd chain lengths to even chain lengths can indicate the state of alkane degradation. Fresh plant material typically biosynthesizes alkanes with odd chain lengths (Bush and McInerney, 2013), which are degraded over time to alkanes with a near equal number of even and odd chain lengths (Bray and Evans, 1961). For example, alkane biomarker analyses have been completed on Athabasca Glacier in Canada and were found to represent carbon inputs of mossy and vascular plant origin (Xu et al., 2010) with a preference of odd chain lengths, indicating fresh carbon sources to the system. In this study, alkane biomarkers are used to show the relative contribution of terrestrial, aquatic, and microbial carbon to the bulk cryoconite material.
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Effects of pumice mining on soil quality

Effects of pumice mining on soil quality

respiration (García-Orenes et al., 2010). Soil microbial quo- tients in several ecosystems have been found to increase im- mediately post-disturbance and subsequently decline with age (Insam and Domsch, 1988; Schipper et al., 2001; Gra- ham and Haynes, 2004). This pattern of microbial quotient has been interpreted as indicative of a decrease in C bio- availability in the soil organic matter over time. The micro- bial quotient of 0 year old was higher than other mine soils, and it tended to increase with age. The respiration rate per unit of microbial biomass (respiratory quotient) is a variable that can be interpreted more easily (Fernandes et al., 2005).
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Physicochemical characterisation of combustion particles from vehicle exhaust and residential wood smoke

Physicochemical characterisation of combustion particles from vehicle exhaust and residential wood smoke

fied. However, there is agreement in the literature that Benzo(a)pyrene is the most carcinogenic PAH, and that several have been found to be mutagenic [16,46]. Since the PAH profiles for Wood and the tunnel samples were found to be similar, the higher content of PAHs in the wood smoke particles indicates a higher mutagenic poten- tial compared to vehicle exhaust. The actual contribution from wood combustion to ambient particle concentra- tions is likely to vary considerably with location and sea- son, and the human exposure may be lower than the emission estimates for wood combustion of 65% [24]. However, based on ambient air measurements in Elverum, Norway, the contribution from residential wood combustion to fine particulate carbon has been estimated to be 65% [48], confirming that residential wood com- bustion is indeed a very important source to particulate air pollution in Norway.
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Organic Carbon, Nitrogen and Phosphorus Contents of Some Tea Soils

Organic Carbon, Nitrogen and Phosphorus Contents of Some Tea Soils

The experimental data for OC, OM, TN, C/N and AP have been analyzed by using Two- way ANOVA to see the effect of topography as well as depth on the measured parameters. The values of F statistics, probability (applicability of null hypothesis) and least significant difference at 95% confidence level (LSD 0.05) are tabulated in (Table 2) and (Table 3). F values for OC, OM, TN and AP due to topographic variations are found to be 13.814, 13.808, 47.391 and 27.035 respectively (Table 2). These values of F are significant at 0.00 level i e. topographic variations have a significant effect on OC, OM, TN and AP content of the studied soils. On the other hand, value of F (0.062) with a high probability value (0.9403) indicate that the variation of topography has almost no effect on C/N i.e. null hypothesis is valid for this parameter. While working for different soil depths it has been found that F values for OC, OM and TN are 7.661, 7.726 and 7.090 respectively (Table 3). These values of F are significant at less than 0.25 % level. These indicate that OC, OM and TN values also vary significantly with soil depths. F statistics for C/N and AP are 1.453 and 2.206, respectively, which are not significant at more than 10% level and indicate that C/N and AP do not vary significantly with soil depths.
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