Rhizosphere chemistry in an ammonium sulfate and water manipulated Norway spruce [Picea abies(L.) Karst.] forest

1997 ◽  
Vol 77 (4) ◽  
pp. 525-533 ◽  
Author(s):  
S. Clegg ◽  
G. R. Gobran ◽  
X. Guan
Keyword(s):  
Organic Matter ◽  
Ammonium Sulfate ◽  
Norway Spruce ◽  
Tree Growth ◽  
Water Soluble ◽  
Base Saturation ◽  
Bulk Soil ◽  
Exchange Reactions ◽  
Soil Fractions ◽  
Uptake Of Nutrients

The purpose of this study was to examine how the treatments ammonium sulfate, drought and irrigation changed chemical characteristics of three soil fractions (bulk soil, rhizosphere and soil root interface (SRI)) from E, Bh and Bs horizons of Podzol in a Norway spruce stand in southwestern Sweden. Regardless of the treatment, the properties of the rhizosphere and SRI nearly always differed from the bulk soil due to the high quantity of organic and root material. Irrigation and ammonium sulfate raised water soluble cations and base saturation in the bulk soil. This was possibly due to leaching from the humus and exchange reactions. In the rhizosphere and SRI, irrigation and ammonium sulfate lowered soluble base cations (BC) and base saturation when compared with control; this is attributed to a combination of leaching and high nutrient demand by trees creating a zone of relative depletion. Drought accumulated more organic matter (OM), acidity and cations in the soil fractions suggesting that the lack of water limited transport and uptake of nutrients. Generally, the magnitude of accumulation/depletion of nutrients in the soil fractions reflected the degree of stress which was in turn linked to root uptake of nutrients or to tree growth. Due to the apparent linkage between tree growth, uptake of nutrients and rhizosphere chemistry, we emphasise that soils must be studied at the rhizospheric rather than the bulk soil scale to further understand the effects of environmental stresses. Key words: Ecosystem manipulation, conceptual model, irrigation, organic matter, relative depletion, soil root interface

Rhizospheric P and K in forest soil manipulated with ammonium sulfate and water

1997 ◽  
Vol 77 (4) ◽  
pp. 515-523 ◽  
Author(s):  
Stephen Clegg ◽  
George R. Gobran
Keyword(s):  
Organic Matter ◽  
Ammonium Sulfate ◽  
Norway Spruce ◽  
Tree Growth ◽  
Limiting Factor ◽  
Organic P ◽  
Inorganic P ◽  
Soil Fractions ◽  
Extractable P ◽  
P Fraction

This study shows how the stress manipulations, ammonium sulfate, drought and irrigation changed the P and K status of three soil fractions (bulk soil, rhizosphere and soil-root interface) from E, Bh and Bs horizons of a Norway spruce stand in southwestern Sweden. The results indicate that dynamic linkages exist between the three soil fractions and tree growth. Accumulation rather than depletion of P and K were observed in the vicinity of the roots which we attribute primarily to accumulated organic matter and high rates of mineralization. Relative depletion of P and K around roots resulted from treatments that stimulated tree growth and P and K uptake. The ratio of organic P, the largest extractable P fraction, to inorganic P indicated that organic P is an important P resource when inorganic P is heavily utilized in treatments where growth has increased. There are indications that K supply was reduced by stimulating growth with ammonium sulfate and irrigation, suggesting that K rather than P can become the second limiting factor to growth at this site after N. Key words: Organic matter, available P and K, relative depletion, Norway spruce, ecosystem manipulation, conceptual model, environmental stress

A conceptual model for nutrient availability in the mineral soil-root system

1996 ◽  
Vol 76 (2) ◽  
pp. 125-131 ◽  
Author(s):  
George R. Gobran ◽  
Stephen Clegg
Keyword(s):  
Organic Matter ◽  
Conceptual Model ◽  
Norway Spruce ◽  
Mineral Soil ◽  
Organic Matter Content ◽  
Base Cations ◽  
Titratable Acidity ◽  
Matter Content ◽  
Bulk Soil ◽  
Soil Fractions

We propose a conceptual model based on our results from rhizospheric studies of a Norway spruce stand growing on a nutrient poor Podzol in Southwest Sweden. We assume that dynamic linkages exist between three soil fractions: bulk soil, rhizosphere (Rhizo) and soil root interface (SRI). The soil fractions were characterized by organic matter content, electrical conductivity, pH, and soluble and exchangeable cations. Analyses showed great differences among the three soil fractions, especially the properties of the SRI. Cation exchange capacity and base saturation were higher in the rhizosphere and SRI than in the bulk soil. We attribute this to accumulation of organic matter (OM) in the rhizosphere and SRI. Moreover, the rhizosphere and SRI fractions had lower pH and higher titratable acidity than the bulk soil. Any possible negative effects of Al to the roots could be offset by accumulated organic matter and base cations (BC). The calcium-aluminum balance followed a consistent trend: bulk < rhizo < SRI. The results suggest that soil around the roots exhibits a different chemical composition than that of the root-free (bulk) soil, indicating more favorable conditions for roots. We suggest that trees growing on nutrient-poor acid soils invest their energy around roots to create a favorable microenvironment for both roots and microorganisms. Our results suggest that existing models which attempt to connect tree growth to soil acidification need modification. Such modification would include horizontal variation (bulk soil, rhizo and SRI) besides the vertical ones normally emphasized. It is possible that the conceptual model may enable a better understanding and description of naturally existing relationships between soil and plants under normal and stressed conditions. Key words: Conceptual model, organic matter, rhizosphere, soil root interface, acidification and growth models, Norway spruce

scholarly journals Fractionation, Characterization and Speciation of Lead in the Industrially Polluted Soils of Tejgaon Area of Bangladesh and Lead Pollution of Associated Plants and Water

1970 ◽  
Vol 46 (3) ◽  
pp. 277-290
Author(s):  
MN Mondol ◽  
AS Chamon ◽  
B Faiz ◽  
MH Rahman ◽  
SF Elahi
Keyword(s):  
Organic Matter ◽  
Soil Ph ◽  
Rainy Season ◽  
Organic Matter Content ◽  
Industrial Area ◽  
Dry Season ◽  
Water Soluble ◽  
City Centre ◽  
Soil Fractions ◽  
Tolerable Level

The Tejgaon industrial area is located within the Dhaka Municipality area and about 5 km north of the city centre. At Tejgaon soil pH was around neutrality (mean 6.73) although the minimum value was 5.3 and the maximum 7.6. High buffering capacity resulting from high soil organic matter content (4.87-11.55%) probably influenced soil pH to a neutral value. Electrical conductivity (EC) (25-551 μS), organic matter (OM) (4.87-11.55%) and nitrogen (N) contents were also influenced by the industrial wastes and effluents of the factories. The average Pb concentrations (mg/kg) in different soil fractions were 7.80, 21.85, 56.15 and 130.29 and 11.42, 20.27, 40.33 and 95.08 in water-soluble, NH4OAc extractable, DTPA ( Dietheline-Triamine-Penta-Acetic acid) extractable and total fractions during dry (January) and rainy seasons (September) respectively. Comparing 1st (rainy season) and 2nd (dry season) sampling data, Pb concentrations in different soil fractions were higher in the 2nd sampling data. Concentration of total Pb in soils during 1st sampling were found above the natural background level with few exceptions. Only 4% of total Pb (=20 mg kg-1) samples were in the normal range during wet season. Lead concentration in the group of tolerable level was 58% (>20-<=100 mg kg-1) and 38% (>=100 mg kg-1) were found in the group of in excess of tolerable level during 1st sampling. On the other hand 62.5% (>=100 mg kg-1) were found in the group of in excess of tolerable level (0.01 mg kg-1 Pb) during dry season. In case of water samples, total Pb concentration in the rainy season, all samples were found in the group of in excess of tolerable level during 1st sampling. Plant samples were found to contain untolerable total Pb (>20 mg kg-1) during rainy and dry seasons, respectively. Key words: Speciation; Tejgaon soil; Industrial area; Lead. DOI: http://dx.doi.org/10.3329/bjsir.v46i3.9032 BJSIR 2011; 46(3): 277-290

scholarly journals A Novel Approach to Evaluate the Effect of Neighboring Trees and the Orientation of Tree Social Area on Stem Radial Increment of Norway Spruce Trees

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 163
Author(s):  
Jan Světlík ◽  
Jan Krejza ◽  
Pavel Bednář
Keyword(s):  
Norway Spruce ◽  
Tree Growth ◽  
Growth Models ◽  
Explanatory Power ◽  
Radial Increment ◽  
Important Indicator ◽  
The Czech Republic ◽  
Novel Approach ◽  
Spruce Stands ◽  
Social Area

Tree growth depends on many factors such as microsite conditions, vitality, and variations in climate and genetics. It is generally accepted that higher growth indicates both an economic benefit and better vitality of any tree. Here we use a modified approach of evaluating tree social area to study mutual tree competition based on the orientation and shape of trees social area. The investigation was performed in nine Norway spruce stands in the Czech Republic. The objective of this study performed from 2008 to 2012 was to quantify relative tree radial increments with respect to the lowest and highest competition found in specific sectors of tree social area (AS). Specific groups of trees (tree classes) were evaluated according to their classes (dominant, co-dominant and sub-dominant) and their composition status in ninety-degree sectors of AS using established classifying rules. The results showed that a spatially-available area (AA) is an inappropriate parameter for predicting tree growth, whereas AS provided robust explanatory power to predict relative radial growth. Tree size was observed as an important indicator of relative radial increments. A significantly positive correlation was found for a radial increment of sub-dominant trees with the lowest competition from western directions; whereas a negative correlation was observed when the lowest competition was observed from eastern directions. For dominant trees, there was an evident growth reaction only when more than 50% of the AS was oriented towards one of the cardinal points. Individual differences in the orientation of tree AS may be important parameters with regard to competition and its spatial variability within an area surrounding a particular tree and deserve more detailed attention in tree growth models and practice.

scholarly journals Biotic and Abiotic Determinants of Soil Organic Matter Stock and Fine Root Biomass in Mountain Area Temperate Forests—Examples from Cambisols under European Beech, Norway Spruce and Silver Fir (Carpathians, Central Europe)

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 823
Author(s):  
Anna Zielonka ◽  
Marek Drewnik ◽  
Łukasz Musielok ◽  
Marcin K. Dyderski ◽  
Dariusz Struzik ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Norway Spruce ◽  
Root Biomass ◽  
Fine Root ◽  
Stand Density ◽  
European Beech ◽  
Fine Root Biomass ◽  
Silver Fir ◽  
Beech Forests

Forest ecosystems significantly contribute to the global organic carbon (OC) pool, exhibiting high spatial heterogeneity in this respect. Some of the components of the OC pool in a forest (woody aboveground biomass (wAGB), coarse root biomass (CRB)) can be relatively easily estimated using readily available data from land observation and forest inventories, while some of the components of the OC pool are very difficult to determine (fine root biomass (FRB) and soil organic matter (SOM) stock). The main objectives of our study were to: (1) estimate the SOM stock; (2) estimate FRB; and (3) assess the relationship between both biotic (wAGB, forest age, foliage, stand density) and abiotic factors (climatic conditions, relief, soil properties) and SOM stocks and FRB in temperate forests in the Western Carpathians consisting of European beech, Norway spruce, and silver fir (32 forest inventory plots in total). We uncovered the highest wAGB in beech forests and highest SOM stocks under beech forest. FRB was the highest under fir forest. We noted a considerable impact of stand density on SOM stocks, particularly in beech and spruce forests. FRB content was mostly impacted by stand density only in beech forests without any discernible effects on other forest characteristics. We discovered significant impacts of relief-dependent factors and SOM stocks at all the studied sites. Our biomass and carbon models informed by more detailed environmental data led to reduce the uncertainty in over- and underestimation in Cambisols under beech, spruce, and fir forests for mountain temperate forest carbon pools.

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