Effects and importance of indigenous earthworms on decomposition and nutrient cycling in coastal forest ecosystems

1986 ◽  
Vol 16 (5) ◽  
pp. 983-989 ◽  
Author(s):  
G. A. Spiers ◽  
D. Gagnon ◽  
G. E. Nason ◽  
E. C. Packee ◽  
J. D. Lousier
Keyword(s):  
Forest Ecosystems ◽  
Coastal Forest ◽  
Mixed Stands ◽  
Earthworm Casts ◽  
Earthworm Species ◽  
Podzolic Soils ◽  
Availability Analysis ◽  
High Nutrient ◽  
Organic Horizons ◽  
Population Numbers

The general ecology of an undescribed indigenous earthworm species in the Megascolecidae, found in the organic horizons of Podzolic soils under mixed stands of Tsugaheterophylla, Abiesamabilis, Thujaplicata, and Pseudotsugamenziesii, is described. The earthworm is a member of the genus Arctiostrotus. Over a range of sites, population numbers of earthworms were correlated to rooting concentration in and immediately below the mor humus. By micromorphological examination, earthworm casts were found to account for up to 60% by volume of the constituent solids of the organic horizons. The abundance of both fine roots and fungal hyphae in the worm casts suggested high nutrient availability. Analysis of fresh faecal material showed a marked increase in most important nutrients (N, P, K, Mg, Fe, Na) relative to levels in noningested litter. Observations indicate that this earthworm species, whose population density may reach 200 m−2, has a major role in the decomposer subsystem of these ecosystems.

scholarly journals Using remote sensing to assess tsunami-induced impacts on coastal forest ecosystems at the Andaman Sea coast of Thailand

2010 ◽  
Vol 10 (4) ◽  
pp. 729-745 ◽  
Author(s):  
H. Roemer ◽  
G. Kaiser ◽  
H. Sterr ◽  
R. Ludwig
Keyword(s):  
Remote Sensing ◽  
Forest Ecosystems ◽  
Ground Truth ◽  
Andaman Sea ◽  
Coastal Forest ◽  
Coastal Forests ◽  
Change Detection Algorithms ◽  
Damage Maps ◽  
2004 Tsunami ◽  
Sea Coast

Abstract. The December 2004 tsunami strongly impacted coastal ecosystems along the Andaman Sea coast of Thailand. In this paper tsunami-induced damage of five different coastal forest ecosystems at the Phang-Nga province coast is analysed with a remote sensing driven approach based on multi-date IKONOS imagery. Two change detection algorithms, change vector analysis (CVA) and direct multi-date classification (DMC), are applied and compared regarding their applicability to assess tsunami impacts. The analysis shows that DMC outperforms CVA in terms of accuracy (Kappa values for DMC ranging between 0.947 and 0.950 and between 0.610–0.730 for CVA respectively) and the degree of detail of the created change classes. Results from DMC show that mangroves were the worst damaged among the five forests, with a 55% of directly damaged forest in the study area, followed by casuarina forest and coconut plantation. Additionally this study points out the uncertainties in both methods which are mainly due to a lack of ground truth information for the time between the two acquisition dates of satellite images. The created damage maps help to better understand the way the tsunami impacted coastal forests and give basic information for estimating tsunami sensitivity of coastal forests.

Formation forest fitotsenozov Volga River right banks

10.12737/3833 ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. 149-152 ◽  
Author(s):  
Ульданова ◽  
Railya Uldanova
Keyword(s):  
Forest Ecosystems ◽  
Biological Diversity ◽  
Jaccard Coefficient ◽  
Coastal Forest ◽  
Coastal Forests ◽  
Natural Habitats ◽  
Volga River ◽  
Floristic Similarity ◽  
Α Diversity ◽  
Mixed Grass

The coastal forests, presented by valuable deciduous and coniferous forests, grow in the northeastern and eastern parts of the Volga region of the Republic of Tatarstan, skirting the high right bank of the Volga River. They contribute to the maintenance of biological diversity in nature. The study of the formation of coastal forest phytocenoses, their species diversity and the modern state is now urgent work, and development activities for the conservation of natural habitats of plants, improve the sustainability of forest ecosystems are perspective direction. According to research of the forests of the right bank of the river Volga, we present the structure of coastal forest ecosystems. The association of forest ecosystems to the various elements of the relief was installed. The types of soil and litter were presented. The estimation of α-diversity of vascular herbaceous plants and ß-diversity of the studied forest ecosystems were reported. The largest number of species of vascular plants in coastal forests are: oak plant communities; a second group includes birch plants, pine and willow; the third group - the lime and larch; the fourth group - maple plant communitie. The ß-diversity index (Whittaker’s index) of plants in the studied forests varies between 2.2-6.8. The Jaccard coefficient of floristic similarity between forest ecosystems varies from 0.01 to 0.30, which confirms the diversity of generated by coastal forest ecosystems. The greatest diversity of plants was found in forests of ash and mixed grass, mixed grass willow, oak and lime-grove, maple, ash and mixed grass larches, birch wood. The forestry activities in coastal areas should be aimed at creating productive, sustainable forest ecosystems with a rich biodiversity of flora and fauna.

The effect of elemental sulfur on certain chemical and biological properties of surface organic horizons of a forest soil

1986 ◽  
Vol 16 (5) ◽  
pp. 1050-1054 ◽  
Author(s):  
D. G. Maynard ◽  
J. J. Germida ◽  
P. A. Addison
Keyword(s):  
Forest Ecosystems ◽  
Elemental Sulfur ◽  
Sulfur Oxidation ◽  
Nutrient Status ◽  
Biological Properties ◽  
Sulfur Source ◽  
Gas Processing ◽  
Organic Horizons ◽  
Decreasing Ph ◽  
Considerable Damage

Elemental sulfur is a by-product of sour natural gas processing in Alberta, Canada. Breakup and weathering of the storage elemental sulfur blocks has resulted in the deposition of large amounts of elemental sulfur into adjacent forest ecosystems. This has caused considerable damage to the understory vegetation. Certain chemical and biological properties of surface organic forests horizons (LFH) that have been exposed to elemental sulfur for several years were examined over a 2-year period. Increasing concentrations of elemental sulfur (4 100 to 50 400 mg S kg soil−1) and 1.0 M NH4Cl extractable S and decreasing pH (4.4 to 2.4) occurred in the LFH with increasing proximity (750, 250, and 50 m) to the elemental sulfur source. Thiobacillusthiooxidans appeared to be the main organism responsible for elemental sulfur oxidation in all LFH samples. The site immediately adjacent to the elemental sulfur block (50 m) showed reduced concentrations of total and 1.0 M NH4Cl extractable Ca, Mg, K, and Mn. In addition, in the 2nd year of sampling, CO2 respiration in nonamended and glucose-amended samples was significantly reduced. The other sites (250 and 750 m from the block) showed no significant decrease in nutrient status or heterotrophic microbial activity.

scholarly journals Application of the BDq method to complex tropical mixed forest ecosystems in Nigeria

2021 ◽  
Vol 349 ◽  
pp. 41-54
Author(s):  
Friday Nwabueze OGANA ◽  
José Javier GORGOSO-VARELA ◽  
Alfred Ossai ONEFELI
Keyword(s):  
Forest Ecosystems ◽  
Management Practice ◽  
Mixed Forest ◽  
Basal Area ◽  
Selection Method ◽  
Maximum Diameter ◽  
Mixed Stands ◽  
Mixed Forests ◽  
Breast Height ◽  
Silvicultural Treatments

The absence of management practice/silvicultural treatments in the complex tropical mixed forests of Nigeria has led to uncontrolled logging in natural forest stands and loss of biodiversity. To sustain production, protection and conservation in these complex tropical mixed stands, this study proposes the application of a selection method – the BDq method (B: basal area, D: maximum diameter, q-ratio) to manage these stands. Two strata were used as a pilot test: stratum 1 consisted of 15 plots and stratum 2 of 7 plots, each with an area of 0.25 ha. Only trees with a diameter at breast height (d) ≥ 10.0 cm were considered in this study. Harvesting with the BDq method was quantified, by setting B at 20 m2, 25 m2 and 30 m2/ha corresponding respectively to intensive, medium and light harvesting regimes. D was set at 65 cm and the q-ratio was computed for each plot. The results showed that the three BDq regimes prescribed (intensive, medium and light) yielded reasonable felling intensities (FI), derived as the percentage of extracted volume (Vext) and biomass (Wext). The Vext and FI for stratum 1 ranged from 39.94-62.30 m3/ha and 11.22-18.18%; the results for stratum 2 were 30.44-51.33 m3/ha and 10.02-17.57%. For biomass, the Wext and FI ranged from 18.46-29.82 t/ha and 9.40-15.95% for stratum 1 and 14.16-24.82 t/ha and 9.73-17.50% for stratum 2. These findings show that applying the BDq method to the complex tropical mixed forests of Nigeria would yield attractive stands.

scholarly journals Modification of root density in pot experiments with two tropical earthworm species.

2010 ◽  
Vol 26 (2) ◽  
Author(s):  
George G. Brown ◽  
André Kretzschmar ◽  
José C. Patrón
Keyword(s):  
Root Density ◽  
Shoot Biomass ◽  
Transparent Plastic ◽  
Earthworm Casts ◽  
Pasture Grass ◽  
Earthworm Species ◽  
Resistance To Stress ◽  
Induced Changes ◽  
Distribution Of Roots

Three greenhouse experiments were performed to assess the role of two common tropical geophagous endogeic earthworm species, Pontoscolex corethrurus and Polypheretima elongata, on root density of several plant species in two soil types, a clayey Andosol and a sandy Alfisol, from Veracruz, Mexico. The equivalent of about 12 kg dry soil were placed into 20 l plastic pots and 3-14 individuals were inoculated to pots planted with common beans (Phaseolus vulgaris), Brachiaria decumbens pasture grass under four P fertilization regimes (0, 1.6, 8.4 and 10 kg P ha-1) and maize (Zea mays) with or without surface residues. Pots received only one species of earthworms (either P. corethrurus or P. elongata). At harvest, the pots were cut in half and a transparent plastic sheet (overheads) used to draw root and earthworm structures (burrows, casts) in vertical and horizontal (every 5 cm) planes. The drawings were scanned, binarized and submitted to image analysis techniques to determine the density of roots, casts and burrows. Root density was generally higher and there was a trend for more even distribution of roots in the soil, both horizontally and vertically, in the presence of earthworms. Nevertheless, few relationships were observed between root density and shoot biomass or the density of earthworm casts and burrows. A more diffuse (less aggregated) root distribution due to earthworms may aid plants in resistance to stress, although the induced changes in the root system may not necessarily lead to greater yields.

scholarly journals Use of public Earth observation data for tracking progress in sustainable management of coastal forest ecosystems in Belize, Central America

2020 ◽  
Vol 245 ◽  
pp. 111798
Author(s):  
Emil A. Cherrington ◽  
Robert E. Griffin ◽  
Eric R. Anderson ◽  
Betzy E. Hernandez Sandoval ◽  
Africa I. Flores-Anderson ◽  
...  
Keyword(s):  
Central America ◽  
Sustainable Management ◽  
Forest Ecosystems ◽  
Earth Observation ◽  
Observation Data ◽  
Coastal Forest ◽  
Earth Observation Data

The effects of simulated acid precipitation in the surface horizons of two eastern Canadian forest Podzol soils

1987 ◽  
Vol 17 (9) ◽  
pp. 1138-1143 ◽  
Author(s):  
D. J. Thacker ◽  
G. K. Rutherford ◽  
G.W. Vanloon
Keyword(s):  
Mineral Soil ◽  
Acid Precipitation ◽  
Exchange Capacity ◽  
Soil Core ◽  
X Ray Diffraction ◽  
Total N ◽  
Organic C ◽  
Podzolic Soils ◽  
Humus Layer ◽  
Organic Horizons

Undisturbed 18-cm soil cores of the L, F, H, Ae, and upper Bhf horizons of Ferro-Humic Podzols from the Turkey Lake Watershed (Ontario) and Montmorency Forest (Quebec) were treated in the laboratory with 10 m of simulated acid precipitation at pH 5.7, 3.5, and 2.0 over approximately 1 year. Leachate samples were collected from the bottom of the humus layer and the bottom of the soil core and the soils were analyzed at the completion of leaching. The soils from the two sites behaved similarly. Anion concentrations in the leachates adjusted to input levels after approximately 2 m of simulated rainfall. Leaching generally produced an initial flush of cations followed by lower concentrations. The pH 2.0 treatment caused major changes in some soil properties; the pH 3.5 and 5.7 treatment had a more modest effect. Base saturation was markedly reduced following the pH 2.0 treatment, slightly reduced following the pH 3.5 treatment, and slightly increased following the distilled water treatment. Cation exchange capacity was reduced only in the organic horizons receiving pH 2.0 treatment. Organic C, total N, and C/N ratios showed no changes on acidification. Leaching of Fe and Al was only substantial with the pH 2.0 treatment and much more Al than Fe was mobilized. Bicarbonate – extractable P in the mineral soil was doubled by the pH 2.0 treatment compared with the other treatments. X-ray diffraction of clays indicated a loss of hydroxyaluminum interlayers with increasing acidity, which is a stage in the acidic transformation of micaceous to smectite-like materials in Podzolic soils.

The role of organic horizons and canopy to modify the chemistry of acidic deposition in some forest ecosystems

1995 ◽  
Vol 85 (3) ◽  
pp. 1119-1124 ◽  
Author(s):  
H. Shibata ◽  
F. Satoh ◽  
Y. Tanaka ◽  
T. Sakuma
Keyword(s):  
Forest Ecosystems ◽  
Acidic Deposition ◽  
Organic Horizons
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