We repeated the experiment once in adjacent plots located within

We repeated the experiment once in adjacent plots located within the same stands as above. Coppices were harvested annually for three years and evaluated for damage, height, branching, mortality, and biomass. Three treatments: insects, rust fungus, and their combination caused higher levels of coppice damage and mortality compared to controls; these three treatments also reduced plant height, branching, and biomass of surviving coppices. These impacts of insects and rust-fungus-combination were additive on cut-stump and coppice stem mortality, and reduction in height, branching,

leaf biomass, and total biomass of coppices. The rust fungus and psyllid showed better ability to co-attack the Gamma-secretase inhibitor same leaf tissues compared to the rust fungus and the weevil. In conclusion, find more overall effects

of the three natural enemies led to markedly reduced performance of the invasive tree melaleuca. Published by Elsevier Inc.”
“Previous field and laboratory studies have concluded that suspension-feeding detriti vorous fish such as gizzard shad Dorosoma cepedianum selectively ingest nutrient-rich particles using either mechanical sorting within the oropharyngeal cavity or behavioral selectivity within the environment, but none have distinguished between these hypothesized selection mechanisms. To determine whether mechanical selectivity occurs within the oropharyngeal cavity, gizzard shad were fed particles of standardized size but different carbon and nitrogen content in homogeneous particle suspensions

vs. non-homogeneous particle distributions. By comparing foregut and epibranchial organ contents with the particles available in a homogeneous suspension, we demonstrated that the fish did not use mechanical selection for nutrient-rich particles. Previously published hypotheses for intraoral selection of nutrient-rich particles in gizzard shad using crossflow filtration or gustatory receptors were not supported. However, when particles with different nutrient content were allowed to settle AZD1152-HQPA in a heterogeneous distribution, the nutrients in the foregut and epibranchial organs were 1.5 times higher than those of particles in the water and 2.5 times higher than those of settled particles (p <= 0.0001). As a test of one potential behavioral mechanism of particle selection, disturbance of the sediment-water interface resulted in significantly higher organic carbon (p = 0.01) and nitrogen (p = 0.001) within 1 to 2 cm of the bottom compared to the overlying water and the bottom sediment. Thus, future laboratory and field studies should focus on potential behavioral mechanisms of particle selectivity in detritivorous fish suspension feeding on non-homogeneous distributions of small particles (<< 1 mm).

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