The effect of deforestation on organic debris dams

The transportation of large amounts of dissolved organic carbon (DOC) down a stream within a 15.51-km2 catchment in Alberta, Canada, related directly to events, such as high rainfall and beaver (Castor canadensis) dam failures, that created major disturbances. A 2.3-km section of the stream was drastically altered in June 1994 when a flood wave resulting from a breached beaver dam deposited large amounts of debris and sediment within the section. Results from stream DOC-storage analyses, in which a difference method was used, suggest that the organic-debris dams created by the failed dam event served as both sources and sinks for DOC. Discharge and DOC measurements at hydrometric stations located at intervals along the stream indicated that storage of DOC on the catchment was strongly influenced by the presence of wetlands and beaver. In 1994 and 1995, disturbances occurring during periods totalling 17 days and 28 days accounted for 94% (1374 kg·km2) and 84% (204 kg·km2), respectively, of the amount of DOC exported from the catchment. DOC concentrations in the stream were greatest (77.0 mg·L1) near the top of the catchment and decreased progressively downstream to the catchment outlet, where the mean concentration was 23.3 mg·L1.

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Importance of Organic Debris Dams in the Structure and Function of Stream Ecosystems

Ecology ◽

10.2307/1936830 ◽

1980 ◽

Vol 61 (5) ◽

pp. 1107-1113 ◽

Cited By ~ 388

Author(s):

Robert E. Bilby ◽

Gene E. Likens

Keyword(s):

Structure And Function ◽

Stream Ecosystems ◽

Organic Debris ◽

Debris Dams ◽

And Function

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Application of a Simple Cold Stub to the Direct Observation of Frozen Hydrated Sand

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071508 ◽

1973 ◽

Vol 31 ◽

pp. 212-213

Author(s):

John M. Wehrung ◽

Richard J. Harniman

Keyword(s):

United States ◽

Surface Water ◽

Direct Observation ◽

Controlled Study ◽

Clay Particles ◽

Organic Debris ◽

Rock Formations ◽

Water Tables ◽

Permeable Rock ◽

Natural Means

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.

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Cleaner birds: an overview for the Neotropics

Biota Neotropica ◽

10.1590/s1676-06032010000400025 ◽

2010 ◽

Vol 10 (4) ◽

pp. 195-203 ◽

Cited By ~ 7

Author(s):

Ivan Sazima ◽

Cristina Sazima

Keyword(s):

Marine Mammals ◽

Bird Species ◽

The Body ◽

Domestic Dog ◽

Large Herbivores ◽

Broad Category ◽

Organic Debris ◽

Marine Reptiles ◽

Black Vulture ◽

Do So

Several bird species feed on a variety of external parasites and epibionts, organic debris, dead and wounded tissue, clots and blood, and secretions from the body of other vertebrates (hosts or clients). We present an overview of so called cleaner birds from the Neotropics based on field records, literature, and photo survey. We found that 33 bird species in 16 families practice cleaning even if some of them do so very occasionally. The birds range from the Galápagos ground finch Geospiza fuliginosa to the widespread black vulture Coragyps atratus. Clients mostly are large herbivores such as capybaras, deer, and livestock, but also include medium-sized herbivores such as iguanas and tortoises, and carnivores such as boobies and seals - a few bird species associate with these latter marine mammals. No carnivorous terrestrial mammal client is recorded to date except for a domestic dog, from whose hair black vultures picked organic debris. Some clients adopt particular inviting postures while being cleaned, whereas others are indifferent or even disturbed by the activity of cleaner birds. Capybaras, giant tortoises, and iguanas are among the inviting clients, whereas boobies try to dislodge the 'vampire' finch Geospiza difficilis. Most of the Neotropical cleaner birds may be lumped in one broad category (omnivores that dwell in open areas and associate with large to medium-sized herbivores). A second, restricted category accommodates some species from Patagonia and the Galápagos Islands (omnivores that dwell in open areas and associate with carnivorous marine mammals, or seabirds and marine reptiles). Two still more restricted categories accommodate the following: 1) forest-dwelling cleaner birds; and 2) marine coastal cleaners. Additional records of Neotropical cleaner birds will mostly fall in the broad category.

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Blooms of bryozoans and epibenthic diatoms in an urbanized sandy Beach (Balneário Camboriú - SC - Brazil): dynamics, possible causes and biomass characterization

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592017116106504 ◽

2017 ◽

Vol 65 (4) ◽

pp. 678-694 ◽

Cited By ~ 1

Author(s):

Leonardo Rubi Rörig ◽

Maevi Ottonelli ◽

Ana Gabriela Itokazu ◽

Marcelo Maraschin ◽

João Vitor Heberle Lins ◽

...

Keyword(s):

Saturated Fatty Acids ◽

Experimental Studies ◽

Growth Conditions ◽

Adjacent Area ◽

High Concentration ◽

Local Pollution ◽

Organic Debris ◽

Quality Of Water ◽

Low Concentrations ◽

Environmental Health Problem

Abstract Balneário Camboriu (SC - Brazil) is a touristic city where the disordered growth of the urban population and the implementation of coastal works without proper evaluation generated environmental impacts and affected the sanitary quality of water and sediment of Camboriu River and marine adjacent area. One of the most recent and alarming phenomena observed are the blooms of invasive bryozoans (Arboscuspis bellula and Membraniporopsis tubigera) associated with epibenthic diatoms (Amphitetras antediluviana and Biddulphia biddulphiana). Several clues associate these phenomena, started in 2003, with the excess of nutrients and organic matter in the Camboriú cove and large coastal works such as dredging, landfills and construction of jetties, leading to changes in benthic ecological structure. Being an aesthetic and environmental health problem, the concern of the scientific community and government agencies intensified as the occurrences become more frequent and persistent. This research addresses this issue through environmental and experimental studies. Samplings of the benthic material collected by boat and diving, and blooms monitoring were the environmental approach. The laboratory work included the algal isolation and culture, in addition to growth conditions assessment and chemical biomass analysis. Monitoring data showed a seasonal trend in the blooms, with more conspicuous events in warmer months. Diatoms increase in abundance in colder months and bryozoans in the warmer ones. The diatom A. antediluviana, predominant in the blooms, grew satisfactorily in laboratory cultivation, showing better growth in media with higher concentrations of silicate and phosphate. Bryozoans showed slow growth in laboratory conditions. The deposited material collected in the environment showed low concentrations of saturated fatty acids, but the high biomass suggest a possible use for biofuels production. Biomass samples dominated by bryozoans showed moderate antimicrobial activity against Klebsiella pneumoniae. The explanation for the occurrence of these blooms are still inconclusive, but there is considerable evidence that it is a synergistic effect between the high concentration of bacteria and organic debris in the water related to local pollution and the elimination of natural competitors by coastal works.

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Comparative study of resin sealant and resin modified glass ionomer as pit and fissure sealant

Bangabandhu Sheikh Mujib Medical University Journal ◽

10.3329/bsmmuj.v10i1.31366 ◽

2017 ◽

Vol 10 (1) ◽

pp. 21

Author(s):

Shirin Malek ◽

Mozammal Hossain ◽

Md. Abdul Gafur ◽

Md. Shahjalal Rana ◽

Md. Ali Asgor Moral

Keyword(s):

Glass Ionomer Cement ◽

Good Alternative ◽

Glass Ionomer ◽

Fissure Sealant ◽

Treatment Groups ◽

Organic Debris ◽

Resin Modified Glass Ionomer ◽

Group B ◽

Resin Sealant

<p>The purpose of the present study was to compare the marginal integrity of resin modified glass ionomer cement with that of resin sealant, <em>in vitro</em>. Forty artificial pit and fissure cavities were prepared in occlusal surface of extracted premolar teeth by using ¼ round carbide bur. Cavities were condensed with artificial organic debris followed by cleaning with prophylaxis pumice brush and paste and then separated into two treatment groups. In Group A, 15 fissure cavities were sealed by resin sealant and in Group B, 15 fissure cavities were sealed by resin modified glass ionomer sealant. These specimens were subjected to thermo-cycling followed by dye penetration test. The remaining 5 cavities from each group were analyzed for debris score by the SEM. The results of the microleakage test showed that the efficacy of preventing microleakage of samples sealed by resin modified glass ionomer sealant was higher than the samples sealed by resin sealant. However, no significant differences were found. It can be concluded that use of resin modified glass ionomer sealant is a good alternative for sealing pits and fissures.</p>

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Does Mixing Tree Species Affect Water Storage Capacity of the Forest Floor? Laboratory Test of Pine-Oak and Fir-Beech Litter Layers

Forests ◽

10.3390/f12121674 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1674

Author(s):

Anna Ilek ◽

Małgorzata Szostek ◽

Anna Mikołajczyk ◽

Marta Rajtar

Keyword(s):

Physical Properties ◽

Bulk Density ◽

Tree Species ◽

Forest Floor ◽

Storage Capacity ◽

Water Storage ◽

Pine Needles ◽

Litter Layer ◽

Water Storage Capacity ◽

Organic Debris

During the last decade, tree species mixing has been widely supported as a silvicultural approach to reduce drought stress. However, little is known on the influence of tree species mixing on physical properties and the water storage capacity of forest soils (including the forest floor). Thus, the study aimed to analyze the effect of mixing pine needles and oak leaves and mixing fir needles and beech leaves on hydro-physical properties of the litter layer during laboratory tests. We used fir-beech and pine-oak litter containing various shares of conifer needles (i.e., 0, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%) to determine the influence of the needle admixture on bulk density, total porosity, macroporosity, water storage capacity, the amount of water stored in pores between organic debris and the degree of saturation of mixed litter compared to broadleaf litter (oak or beech). We found that the admixture of fir needles increased the bulk density of litter from 7.9% with a 5% share of needles to 55.5% with a 50% share (compared to pure beech litter), while the share of pine needles < 40% caused a decrease in bulk density by an average of 3.0–11.0% (compared to pure oak litter). Pine needles decreased the water storage capacity of litter by about 13–14% with the share of needles up to 10% and on average by 28% with the 40 and 50% shares of pine needles in the litter layer. Both conifer admixtures reduced the amount of water stored in the pores between organic debris (pine needles more than fir needles).

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Trap Efficiency of Reservoirs, Debris Basins, and Debris Dams

Journal of the Hydraulics Division ◽

10.1061/jyceaj.0000428 ◽

1960 ◽

Vol 86 (2) ◽

pp. 69-87

Author(s):

Charles M. Moore ◽

Walter J. Wood ◽

Graham Renfro

Keyword(s):

Trap Efficiency ◽

Debris Dams

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Aspergillus aculeatus. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056401541 ◽

2003 ◽

Author(s):

Z. Kozakiewicz

Keyword(s):

Geographical Distribution ◽

Geographic Distribution ◽

World Wide ◽

Common Species ◽

Aspergillus Aculeatus ◽

Dry Rot ◽

Organic Debris

Abstract A description is provided for Aspergillus aculeatus. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Not a common species, but it has been isolated from soils and organic debris (CABI BIOSCIENCE, 1999). DISEASES: Causes postharvest dry rot of tomatoes (FAJOLA, 1979). GEOGRAPHIC DISTRIBUTION: World-wide, but with a preference for tropical and subtropical climates.

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