Salt marsh establishment in poorly consolidated muddy systems: effects of surface drainage, elevation, and plant age

It is unclear how urbanization affects secondary biological production in estuaries in the southeastern USA. We estimated production of larval/juvenile Fundulus heteroclitus in salt marsh areas of North Carolina tidal creeks and tested for factors influencing production. F. heteroclitus were collected with a throw trap in salt marshes of 5 creeks subjected to a range of urbanization intensities. Multiple factor analysis (MFA) was used to reduce dimensionality of habitat and urbanization effects in the creeks and their watersheds. Production was then related to the first 2 dimensions of the MFA, month, and year. Lastly, we determined the relationship between creek-wide larval/juvenile production and abundance from spring and abundance of adults from autumn of the same year. Production in marsh (g m-2 d-1) varied between years and was negatively related to the MFA dimension that indexed salt marsh; higher rates of production were related to creeks with higher percentages of marsh. An asymptotic relationship was found between abundance of adults and creek-wide production of larvae/juveniles and an even stronger density-dependent relationship was found between abundance of adults and creek-wide larval/juvenile abundance. Results demonstrate (1) the ability of F. heteroclitus to maintain production within salt marsh in creeks with a lesser percentage of marsh as long as this habitat is not removed altogether and (2) a density-dependent link between age-0 production/abundance and subsequent adult recruitment. Given the relationship between production and marsh area, natural resource agencies should consider impacts of development on production when permitting construction in the southeastern USA.

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Diseases of perennial bean grasses in Western Siberia

Multifunctional adaptive feed production № 23 (71) ◽

10.33814/mak-2020-23-71-78-81 ◽

2020 ◽

Author(s):

Lyudmila Ashmarina

Keyword(s):

Western Siberia ◽

Weather Conditions ◽

Plant Age ◽

Intensity Of Development ◽

Resistance Of Varieties

The directions and results of many years of research on the development and prevalence of diseases on perennial leguminous grasses (meadow clover, pannonian clover, sainfoin, sowing alfalfa) in Western Siberia are presented. A whole range of diseases was revealed, the intensity of development, which depends on weather conditions, resistance of varieties, plant age, etc.

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