Effects of Habitat-Specific Primary Production on Fish Size, Biomass, and Production in Northern Oligotrophic Lakes

AbstractEcological theory predicts that the relative distribution of primary production across habitats influence fish size structure and biomass production. In this study, we assessed individual, population, and community-level consequences for brown trout (Salmo trutta) and Arctic char (Salvelinus alpinus) of variation in estimated habitat specific (benthic and pelagic) and total whole lake (GPPwhole) gross primary production in 27 northern oligotrophic lakes. We found that higher contribution of benthic primary production to GPPwhole was associated with higher community biomass and larger maximum and mean sizes of fish. At the population level, species-specific responses differed. Increased benthic primary production (GPPBenthic) correlated to higher population biomass of brown trout regardless of being alone or in sympatry, while Arctic char responded positively to pelagic primary production (GPPPelagic) in sympatric populations. In sympatric lakes, the maximum size of both species was positively related to both GPPBenthic and the benthic contribution to GPPWhole. In allopatric lakes, brown trout mean and maximum size and Arctic char mean size were positively related to the benthic proportion of GPPWhole. Our results highlight the importance of light-controlled benthic primary production for fish biomass production in oligotrophic northern lakes. Our results further suggest that consequences of ontogenetic asymmetry and niche shifts may cause the distribution of primary production across habitats to be more important than the total ecosystem primary production for fish size, population biomass, and production. Awareness of the relationships between light availability and asymmetric resource production favoring large fish and fish production may allow for cost-efficient and more informed management actions in northern oligotrophic lakes.

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Carbon allocation to biomass production of leaves, fruits and woody organs at seasonal and annual scale in a deciduous- and evergreen temperate forest

Biogeosciences Discussions ◽

10.5194/bgd-7-7575-2010 ◽

2010 ◽

Vol 7 (5) ◽

pp. 7575-7606 ◽

Cited By ~ 3

Author(s):

M. Campioli ◽

B. Gielen ◽

A. Granier ◽

A. Verstraeten ◽

J. Neirynck ◽

...

Keyword(s):

Primary Production ◽

Interannual Variability ◽

Biomass Production ◽

Residence Time ◽

Forest Canopy ◽

Net Primary Production ◽

Gross Primary Production ◽

Sink Strength ◽

Early Season ◽

Beech Stand

Abstract. Carbon taken up by the forest canopy is allocated to tree organs for biomass production and respiration. Because tree organs have different life span and decomposition rate, the tree C allocation determines the residence time of C in the ecosystem and its C cycling rate. The study of the carbon-use efficiency, or ratio between net primary production (NPP) and gross primary production (GPP), represents a convenient way to analyse the C allocation at the stand level. Previous studies mostly focused on comparison of the annual NPP-GPP ratio among forests of different functional types, biomes and age. In this study, we extend the current knowledge by assessing (i) the annual NPP-GPP ratio and its interannual variability (for five years) for five tree organs (leaves, fruits, branches, stem and coarse roots), and (ii) the seasonal dynamic of NPP-GPP ratio of leaves and stems, for two stands dominated by European beech and Scots pine. The average NPP-GPP ratio for the beech stand (38%) was similar to previous estimates for temperate deciduous forests, whereas the NPP-GPP ratio for the pine stand (17%) is the lowest recorded till now in the literature. The proportion of GPP allocated to leaf NPP was similar for both species, whereas beech allocated a remarkable larger proportion of GPP to wood NPP than pine (29% vs. 6%, respectively). The interannual variability of the NPP-GPP ratio for wood was substantially larger than the interannual variability of the NPP-GPP ratio for leaves, fruits and overall stand and it is likely to be controlled by previous year air temperature (both species), previous year drought intensity (beech) and thinning (pine). Seasonal pattern of NPP-GPP ratio greatly differed between beech and pine, with beech presenting the largest ratio in early season, and pine a more uniform ratio along the season. For beech, NPP-GPP ratio of leaves and stems peaked during the same period in the early season, whereas they peaked in opposite periods of the growing season for pine. Seasonal differences in C allocation are likely due to functional differences between deciduous and evergreen species and temporal variability of the sink strength. The similar GPP and autotrophic respiration between stands and the remarkable larger C allocation to wood at the beech stand indicate that at the beech ecosystem C has a longer residence time than at the pine ecosystem. Further research on belowground production and particularly on fine roots and ectomycorrhizal fungi likely represents the most important step to progress our knowledge on C allocation dynamics.

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Measurement of primary production and community respiration in oligotrophic lakes using the Winkler method

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-319 ◽

1998 ◽

Vol 55 (5) ◽

pp. 1078-1084 ◽

Cited By ~ 53

Author(s):

Richard Carignan ◽

Anne-Marie Blais ◽

Chantal Vis

Keyword(s):

Primary Production ◽

Detection Method ◽

Gross Primary Production ◽

Community Respiration ◽

Oligotrophic Lakes ◽

Respiration Rates ◽

Precision Level ◽

Winkler Method ◽

End Point Detection ◽

Point Detection

The precision of the Winkler method can reach 2 µg ·L-1 if a potentiometric end-point detection method if used and if minor modifications to standard protocols are made. The major sources of variability encountered at this precision level are due to the gradual decrease (1-3 µg ·L-1 ·h-1) in apparent O2 which occurs after reagent addition and to thermal expansion and contraction of the samples during storage. These sources of error can, however, be easily minimized or eliminated. The precision of the proposed protocols for Winkler determinations and metabolic rate measurements allows the detection of gross primary production and community respiration rates as low as 0.7 mg C ·m-3 ·h-1 after 4-h incubations. The methods are therefore adequate for metabolic studies in oligotrophic lakes, where epilimnetic production and respiration rates range between 5 and 50 mg C ·m-3 ·h-1.

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Allometric scaling of estuarine ecosystem metabolism

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1719963115 ◽

2018 ◽

Vol 115 (26) ◽

pp. 6733-6738 ◽

Cited By ~ 3

Author(s):

Nicholas J. Nidzieko

Keyword(s):

Primary Production ◽

Residence Time ◽

Gross Primary Production ◽

Coastal Ecosystems ◽

Ecosystem Metabolism ◽

Estuarine Ecosystem ◽

Empirical Observation ◽

Benthic Primary Production ◽

Size Dependent ◽

Wide Range

There are still significant uncertainties in the magnitude and direction of carbon fluxes through coastal ecosystems. An important component of these biogeochemical budgets is ecosystem metabolism, the net result of organismal metabolic processes within an ecosystem. In this paper, I present a synthesis of published ecosystem metabolism studies from coastal ecosystems and describe an empirical observation that size-dependent patterns in aquatic gross primary production and community respiration exist across a wide range of coastal geomorphologies. Ecosystem metabolism scales to the 3/4 power with volume in deeper estuaries dominated by pelagic primary production and nearly linearly with area in shallow estuaries dominated by benthic primary production. These results can be explained by applying scaling arguments for efficient, directed transport networks developed to explain similar size-dependent patterns in organismal metabolism. The main conclusion from this synthesis is that the residence time of new, nutrient-rich water is a fundamental organizing principle for the observed patterns. Residence time changes allometrically with size in pelagic ecosystems because velocities change by only an order of magnitude across systems that span more than ten orders of magnitude in size. This nonisometric change in velocity with size requires lower specific metabolic rates at larger ecosystem sizes. This change in transport may also explain a shift from predominantly net heterotrophy to net autotrophy with increasing size. The scaling results are applied to the total estuarine area in the continental United States to estimate the contribution of estuarine systems to the overall coastal budget of organic carbon.

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