scholarly journals Leaf Litter Decomposition and Nutrient Dynamics in Woodland and Wetland Conditions along a Forest to Wetland Hillslope

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Song Qiu ◽  
Arthur J. McComb ◽  
Richard W. Bell
Keyword(s):  
Weight Loss ◽  
Microbial Biomass ◽  
Nutrient Dynamics ◽  
Test Site ◽  
Tree Cover ◽  
Field Exposure ◽  
Eucalyptus Marginata ◽  
Substrate Quality ◽  
Litter Weight ◽  
Nutrient Mobility

Leaf litters of jarrah (Eucalyptus marginata Donn ex Sm.) and banksia (Banksia menziesii R. Br.) were decomposed at woodland and wetland conditions for two years to test site influence on the rates of decomposition. Weight loss was rapid in early rains but slowed substantially in the following months, resulting in 2/3 to 1/2 weights remaining after two years of field exposure. Litter weight loss was well described by a two-substrate quality decay model (R2=0.97−0.99), and the half-lives were 2.6–3.2 weeks (labile fraction) and 6.4–6.9 years (recalcitrant fraction) for jarrah, and 1.0–1.7 weeks (labile) and 6.6–9.9 years (recalcitrant) for banksia. The nutrient mobility was K≈Mg≈S>Ca>P, and the losses of K, Mg and S were correlated with the weight loss of litter (R2=0.77−0.94, P<0.03). P mass increased by 129% in jarrah litter and 174% in banksia litter in the woodland site, suggesting woodland with tree cover provided a better habitat for microbial biomass than non-inundated wetland, hence a notable P conservation in the decomposing litter.

scholarly journals Deforested and drained tropical peatland sites show poorer peat substrate quality and lower microbial biomass and activity than unmanaged swamp forest

2018 ◽  
Vol 123 ◽  
pp. 229-241 ◽  
Author(s):  
M. Könönen ◽  
J. Jauhiainen ◽  
P. Straková ◽  
J. Heinonsalo ◽  
R. Laiho ◽  
...  
Keyword(s):  
Microbial Biomass ◽  
Swamp Forest ◽  
Tropical Peatland ◽  
Substrate Quality

scholarly journals Nitric acid and particulate matter measurements at Athens, Greece, in connection with corrosion studies

2009 ◽  
Vol 9 (21) ◽  
pp. 8309-8316 ◽  
Author(s):  
C. Tzanis ◽  
C. Varotsos ◽  
M. Ferm ◽  
J. Christodoulakis ◽  
M. N. Assimakopoulos ◽  
...  
Keyword(s):  
Test Site ◽  
Water Soluble ◽  
Passive Samplers ◽  
Field Exposure ◽  
Exposure Test ◽  
Corrosion Studies ◽  
Long Time ◽  
The University ◽  
The Vertical Distribution ◽  
The Eu

Abstract. For a long time, scientists have been concerned about the effects of air pollution on materials and especially on the monuments of the cultural heritage. The EU funded a project, entitled MULTI-ASSESS, to determine these effects and to develop dose-response functions appropriate for the new multi-pollutant environment. The University of Athens participated in this effort as a targeted field exposure test site. In the present paper, the measurements of the passive samplers, which were exposed during the same period with the samples for corrosion studies, at the Athens station, are presented. The results have shown that only 16.5% of the deposited mass was water soluble. The vertical distribution of passive particle collectors has led to the conclusion that the height of maximum deposition of each ion is different. In addition, a variation of the water-soluble mass to total deposited mass between 8% and 31% was observed.

scholarly journals Precision Agriculture Practices Improves Soil Aggregation, Aggregate Associated Organic Carbon Fractions and Nutrient Dynamics in Cereal-based Systems of North-West India: An Overview

2020 ◽  
pp. 40-53
Author(s):  
S. K. Gupta ◽  
R. K. Naresh ◽  
M. Sharath Chandra ◽  
Kancheti Mrunalini
Keyword(s):  
Microbial Biomass ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Precision Agriculture ◽  
Structural Changes ◽  
Nutrient Dynamics ◽  
Surface Soil ◽  
Significant Proportion ◽  
Land Application ◽  
North West

Precision farming uses proximal and remote sensor surveys to delineate and track in-field variations in soil and crop attributes, directing variable input rate control, such that in-season management can be sensitive, e.g. matching strategic application of nitrogen fertilizer to site-specific conditions. It has the ability to increase productivity in the processing and use of nutrients, ensuring that nutrients do not leach out or accumulate in excessive amounts in areas of the field, causing environmental problems. Tillage systems can change the dynamics of organic carbon in soil and microbial biomass in soil by adjusting aggregate shape and distribution of C within aggregates. The effects of tillage on soil organic carbon (SOC) and soil aggregate nutrient content can differ spatially and temporarily, and for different types of soil and cropping systems. The maximum (19.2 percent) and minimum (8.9 percent) proportion of total aggregated carbon was retained in surface soil, with fractions of 2 mm and 0.1-0.05 mm size respectively. At a depth of 0-7 cm soil MBC under plowing tillage was slightly higher than rotary tillage, but EOC was just opposite. Rotary tillage had much higher soil TOC than plowing tillage at a depth of 7-14 cm. Nevertheless, under plowing tillage, TOC, DOC, and MBC were significantly higher than rotary tillage except for EOC, at 14-21 cm depth. A significant proportion of the total SOC was found to be captured under both surface (67.1 percent) and sub-surface layers (66.7 percent) by the macro-aggregates (2-0.25 mm), leaving rest in micro-aggregates and particles shaped as "silt + clay." Fine POC, LFOC and microbial biomass can be useful early signs of alterations in organic topsoil C. Conversely, LFOC and DOC are important subsoil indicators. Under two tillage regimes, surface soil (0-15 cm) was fractionated into aggregate sizes (4.76 mm, 4.76-2.00 mm, 2.00-1.00 mm, 1.00-0.25 mm, 0.25-0.053 mm, 0.053 mm). Tillage substantially decreased the proportion of macro-aggregate fractions (2.00 mm) and thus improved aggregate stability by 35 per cent relative to RNT, indicating that tillage practices for this subtropical soil resulted in structural changes in soil. The highest SOC was in the fraction of 1.00-0.25 mm (35.7 and 30.4 mg / kg respectively for RNT and CT), while the lowest SOC was in fractions of micro-aggregate (0.025 mm) and silt + clay (0.053 mm) (19.5 and 15.7 mg / kg respectively for RNT and CT). Application of inorganic fertilizer may maintain soil organic carbon (SOC) concentrations, whereas long-term application of manure alone or in combination with NPK (M and NPK + M) may significantly increase SOC content compared to unfertilized land. Application of manure substantially increased the proportion of large macro-aggregates (2000 μm) relative to the regulation, thus resulting in a corresponding decrease in the percentage of micro-aggregates (53-250 μm). The labile element of organic carbon has been suggested as a delicate predictor of soil organic matter changes. Improving the soil organic carbon pool also increases resilience and eco-efficiency of the agro ecosystems.

scholarly journals PSVII-11 Effects of a synbiotic (probiotic+prebiotic) on the reproductive efficiency of multiparous sows

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 217-217
Author(s):  
Shelby Curry ◽  
Erika G Hendel ◽  
Daniel Petri ◽  
Gene G Gourley ◽  
G R Murugesan
Keyword(s):  
Weight Loss ◽  
Reproductive Performance ◽  
Feed Intake ◽  
Mixed Model ◽  
Lactobacillus Reuteri ◽  
Reproductive Efficiency ◽  
Positive Trend ◽  
Lactation Period ◽  
Litter Weight ◽  
Significant Difference

Abstract Sow longevity plays an important role on the profitability of any sow operation in economically and efficiently producing pigs. An experiment was conducted to evaluate the effects of a synbiotic (Biomin® PS, BIOMIN America Inc.) containing multi-strain live probiotic strains (Enterococcus faecium, Pediococcus acidilactici, Bifidobacterium animalis, and Lactobacillus reuteri) and a prebiotic (fructo-oligosaccharaide) on sow reproductive performance. A total of 24 sows (4th and 5th parity) were divided evenly into 2 groups and fed either a control diet or a synbiotic diet during the gestation (starting on d 35 of gestation) at 1 kg/MT and lactation until weaning of piglets at 0.5 kg/MT. Daily sow feed intake was also measured during the lactation period. Sow BW was recorded pre-farrow (d 110 of gestation) and at weaning (d 21 of lactation). Piglet BW was recorded after cross-foster and on d 21 of lactation. Data were analysed using MIXED model in SAS. No significant difference was observed in sow feed intake. Relatively lower weight loss (14%) was observed during lactation in sows fed synbiotic (-24.3 kg/sow) in comparison to control fed sows (-28.4 kg/sow), although not statistically significant. A positive trend (P < 0.10) was observed with synbiotic fed sows having lower still-borns (-50%), increased number of piglets weaned per sow (+0.94 piglet/sow) and litter weight gain (+7.24 kg/litter) compared to control sows during lactation. Weaned litter weight was also increased (P < 0.05) with synbiotic feeding (78.5 kg/sow) in comparison to control (66.5 kg/sow). Overall, supplementation of the synbiotic formulation increased the sow reproductive performance by increasing weaned litter weight and number of pigs weaned while numerically lowering sow weight loss during lactation. Supplementation this synbiotic could be considered as part of sow feeding programs to improve sow reproductive efficiency.

Influence of exposure time, wood species and dimension on the remaining copper and chromium content in CC-treated wood after field and laboratory leaching tests

Holzforschung ◽  
2015 ◽  
Vol 69 (9) ◽  
pp. 1143-1150 ◽  
Author(s):  
Mohsen Bahmani ◽  
Eckhard Melcher ◽  
Olaf Schmidt ◽  
Jörg Fromm
Keyword(s):  
Exposure Time ◽  
Wood Species ◽  
Laboratory Tests ◽  
Treated Wood ◽  
Wood Preservative ◽  
Test Site ◽  
Small Samples ◽  
Field Exposure ◽  
Test Parameters ◽  
Element Contents

AbstractMost studies on preservative depletion from treated wood are performed with small samples on a laboratory scale. Although these studies provided repeatable and constant test parameters, the results have little applicability to real conditions. Therefore, a series of laboratory tests were carried out according to CEN/TS 15119 part 1 and part 2 by means of EN 252 and non-standard sized Scots pine sapwood as well as spruce stakes. The stakes were impregnated by vacuum pressure with chromium (Cr)-copper(Cu)-containing wood preservative. For comparison, a set of 18 stakes per test parameter was installed at a test site (in ground use), whereby, every 4 months, three stakes from each series were removed for analysis. Both the time depending losses of metal as well as the remaining element contents were determined for samples exposed under lab conditions, whereas distribution and remaining element contents were measured for samples exposed in the field. The obtained data were evaluated regarding factors influencing the metal leaching, such as exposure time, wood species, or dimension. The results showed that wood species had a significant effect on the Cu depletion, while it had less influence on the Cr loss. Cr and Cu distribution in the standard and non-standard sized pine sapwood significantly changed as compared to spruce. In addition, comparison of the laboratory and field test results indicated that metal depletion is greater in field exposure compared to both laboratory tests.

Accumulation and release of plant nutrients in decomposing Scots pine needle litter. Long-term decomposition in a Scots pine forest II

1982 ◽  
Vol 60 (8) ◽  
pp. 1561-1568 ◽  
Author(s):  
Håkan Staaf ◽  
Björn Berg
Keyword(s):  
Weight Loss ◽  
Scots Pine ◽  
Nutrient Dynamics ◽  
Pine Forest ◽  
Plant Nutrient ◽  
Pine Needle ◽  
Needle Litter ◽  
Scots Pine Forest ◽  
Net Release

Plant nutrient dynamics in decomposing needle litter were measured during a 5-year period in a Scots pine forest in central Sweden. As seen over the whole 5-year period, the nutrients were retained (to a litter weight loss of about 75%) in the order Mn < Ca < K < Mg < S < N < P. During the first 1.5 years there was a net increase of N and P whereafter a net release took place. A similar but less pronounced development could be seen for S, whereas Ca, K, Mn, and Mg were released from the start of the incubation. It is suggested that P was the most limiting element for microbial activity during this first phase. There appeared to be only little initial leaching from the litter and the different behaviours of the elements could largely be explained by their concentration in litter in relation to the needs of microorganisms and to their solubility. K and Mg were the elements that were released at rates most similar to organic matter weight loss.

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