Faculty Opinions recommendation of Organic matter loading by hippopotami causes subsidy overload resulting in downstream hypoxia and fish kills.

The effects of two total solids contents (TS) and two inocula were studied for the semi-continuous high-solids anaerobic digestion (HS-AD) of cassava pulp under mesophilic conditions (35 ± 2 °C). In the 1.0-L bioreactors, two TS of 15% and 20% with digestate as a sole inoculum were chosen to run the HS-AD, and two inocula (the digestate from the AD of cassava pulp and sewage sludge) were used separately under TS 20%. All treatments were carried out at the organic matter loading rates (OLRs) of from 3.0 to 10.0 kg volatile solids (VS)/(m3·d), with each phase of 6 days followed by two 3-days phases of no feeding and then low OLR of 6.5 kg VS/(m3·d). Compared with TS 15%, the bioreactors of TS 20% with the digestate had a higher buffering capability to alleviate the rapid acidification and a higher level of the specific methane yields (SMYs) of from 0.212 to 0.233 m3/(kgVSadded) at the OLRs of 4.0 to 6.5 kgVS/(m3·d), while TS 15% obtained the highest SMY of from 0.152 to 0.182 m3/(kgVSadded) at the OLR of 4.0, 6.5, and 8.0 kgVS/(m3·d). In contrast, sewage sludge did not restrain the rapid acidification and only yielded quite small SMYs under TS 20%.

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Vegetation dynamics in response to organic matter loading rates in a created freshwater wetland in southeastern Virginia

Wetlands ◽

10.1672/0277-5212(2007)27[936:vdirto]2.0.co;2 ◽

2007 ◽

Vol 27 (4) ◽

pp. 936-950 ◽

Cited By ~ 19

Author(s):

David E. Bailey ◽

James E. Perry ◽

W. Lee Daniels

Keyword(s):

Organic Matter ◽

Vegetation Dynamics ◽

Freshwater Wetland ◽

Loading Rates ◽

Organic Matter Loading

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Floristic shifts in wetlands: the effects of environmental variables on the interaction between Phragmites australis (Common Reed) and Melaleuca ericifolia (Swamp Paperbark)

Marine and Freshwater Research ◽

10.1071/mf07072 ◽

2008 ◽

Vol 59 (3) ◽

pp. 187 ◽

Cited By ~ 14

Author(s):

Kay Morris ◽

Paul I. Boon ◽

Elisa J. Raulings ◽

Sean D. White

Keyword(s):

Organic Matter ◽

Phragmites Australis ◽

Gas Flow ◽

Common Reed ◽

Growth Patterns ◽

Plant Interactions ◽

Eastern Australia ◽

Convective Gas Flow ◽

Short Term Experiment ◽

Organic Matter Loading

Over the past 40–50 years, the woody shrub Melaleuca ericifolia has progressively invaded large areas of Phragmites australis in Dowd Morass, a Ramsar-listed, brackish wetland in south-eastern Australia. To understand the processes underlying this shift we grew Phragmites and Melaleuca alone and together under contrasting sediment organic-matter loadings and salinities. To examine if the capacity of Phragmites to aerate the sediment influenced plant interactions, we also dissipated convective gas flow in some Phragmites plants by perforating their stems. Although Phragmites suppressed the growth of Melaleuca under all conditions, Melaleuca persisted. We did not find Phragmites ramets to be more sensitive to salinity than Melaleuca seedlings. Surprisingly Phragmites did not increase sediment redox and was more sensitive to increased organic-matter loading than Melaleuca. These results do not support the notion that colonisation by Melaleuca was facilitated by a decline in Phragmites at higher salinities or through aeration of the sediments by Phragmites. Seedlings of Melaleuca, however, were easily blown over by wind and it is likely that Phragmites stands shelter Melaleuca during establishment. Although our short-term experiment did not show that Melaleuca was a better competitor, differences in seasonal growth patterns may contribute to a shift in competitive abilities over a longer time scale.

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