Matches in SemOpenAlex for { <https://semopenalex.org/work/W1650347188> ?p ?o ?g. }
Showing items 1 to 77 of
77
with 100 items per page.
- W1650347188 abstract "During my PhD, I focused on metabolic rates of litter- and soil-dwelling invertebrates, parametersthat exert influence on them or are influenced by metabolism. I started with consumption experi-ments, comparing the estimated amounts of energy taken up with the energetic demand estimatedvia metabolic-rate measurements. These experiments showed that, generally, ingestion as wellas metabolic rates increase for beetle and spider species with increasing temperature. However,while ingestion increased only slightly with increasing temperature, metabolic demand increasedstrongly thus reducing the ingestion efficiency with increasing temperature (Chapter 3). This mighthave strong effects on the whole food web in a natural system. Populations might depict a higherstability but on the other hand, due to the lowered ingestion efficiencies, predators might becomemore prone to starvation and even extinction (Chapter 3). In the next study again metabolic ratesand consumption rates (functional responses) were compared across a temperature range, but witha different focus. Here, ground beetles in combination with a more resident and a mobile prey typewere used to examine the different effects of temperature on these predator-prey pairs (Chapter 4).Generally, increasing temperature led to an increase in metabolic rate, a decrease in energetic ef-ficiency and a decrease in handling time. However, the effect of increased temperature on attackrate differed for the two prey types. For mobile prey the attack rate increased with temperature,while it was not affected for the more resident prey. This implies that an increase in temperaturemight stabilize population dynamics. Since the first two studies had shown that the metabolic rateof different organisms is differently affected by body mass and temperature, I focused on the ef-fects of body mass and temperature on metabolic rates for my next study. Therefore, I compiled alarge dataset on metabolic rates of mainly soil-dwelling invertebrates by performing measurementsof respiration and by literature research (Chapter 5). With this dataset I tested a very prominenttheory (Metabolic Theory of Ecology) on how metabolism depends on body mass and temperature.As this theory uses a fixed three-quarter allometric exponent (fixed body-mass dependence), whichthe results of chapter 3 and 4 proved not to be useful, I also used a relaxed version (unrestrictedbody-mass and temperature dependence). Finally, I tested a model, similar to the relaxed one butincorporating phylogenetic information, thus each phylogenetic group would be fit independently.This phylogenetic model obtained the highest quality thus emphasizing the importance of account-ing for the phylogenetic affiliation of an organism (Chapter 5). Thus, the results of this study allowa conservative energy-demand estimation for different terrestrial invertebrate species. Having seen that metabolic rates of organisms as well as their consumption rates increase withtemperature, the question remains how the assimilation efficiencies change. The effect of tempera-ture on the assimilation efficiencies of different consumer types (carnivore, detritivore, herbivore)had not been studied yet. For filling this gap, a database on assimilation efficiencies for differentconsumer types was used and the database on metabolic rates (Chapter 5). Metabolic rates in-creased with temperature for all consumer types while the assimilation efficiency only increasedfor herbivores and was independent of temperature for the other two consumer types (Chapter 6).From this it follows that maintenance consumption rates increase with temperature, however theamount of increase differs between the consumer types. For carnivores the metabolic rates in-creased stronger with increasing temperature than did their consumption rates, which might leadto starvation. Accelerated consumption rates of detritivores could lead to increased turnover ratesand might result in increasing biomass of the populations (Chapter 6). Aside from using the metabolic-rate data with other laboratory data, it may also provide informa-tion on the energy distribution in natural systems while its direct measurement is not possible. Fortesting the Structured Resource Theory of Sexual Reproduction (SRTS) abundance and body-massdata on oribatid mites in differently used habitats were used to estimate the metabolic demand ofthe oribatid community (Chapter 7). The SRTS suggests that limited resources favor sexually re-producing consumers while ample resources would be superiorly exploited by parthenogeneticallyreproducing species. Abundance and metabolic demand served as a surrogate for resource supply.The data supported the predictions of the SRTS as in habitats with a high amount of resources(as indicated by high population densities or high metabolic rates) parthenogenetic reproductionoccurred in a higher proportion (Chapter 7). Finally, I used the metabolic parameters to estimatethe energetic demand of soil-invertebrate communities in differently used forests. Abundances andbody masses (via body lengths) were obtained by field sampling. Based on these data I calculatedthe metabolic demand, the population energy use (PEU) and the biomass of the different speciespresent (Chapter 8). Thus, this dataset allowed testing different patterns that have been describedto apply to energy or biomass distribution in a community. The energetic equivalence is observed ifpopulations of small and large organisms use the same amount of energy. The biomass equivalenceon the other hand states that the biomasses are independent of body mass. I compared the resultswith these patterns. Generally, metabolic rates increased with body mass of the species and abun-dances declined independently of phylogenetic group, land-use type or feeding type. Biomassesincreased in all cases thus clearly rejecting the biomass-equivalence hypothesis. Population en-ergy use mostly increased with body mass. Furthermore, a more detailed analysis (phylogeneticgroups separately in each land-use type) showed that the energetic equivalence is sometimes metand sometimes not. However, the data support predictions of the resource-thinning hypothesis,which states that abundances should decrease with trophic level, and mostly the allometric-degreehypothesis stating that PEU should increase with increasing body mass. Thus, predictions fromfood-web theory regarding the structure of natural communities are met and further integration ofmetabolic and food-web theory might help to explain the natural community structures." @default.
- W1650347188 created "2016-06-24" @default.
- W1650347188 creator A5058117416 @default.
- W1650347188 date "2014-01-01" @default.
- W1650347188 modified "2023-09-27" @default.
- W1650347188 title "Allometry – Relations toEnergy and Abundance" @default.
- W1650347188 hasPublicationYear "2014" @default.
- W1650347188 type Work @default.
- W1650347188 sameAs 1650347188 @default.
- W1650347188 citedByCount "0" @default.
- W1650347188 crossrefType "dissertation" @default.
- W1650347188 hasAuthorship W1650347188A5058117416 @default.
- W1650347188 hasConcept C109931610 @default.
- W1650347188 hasConcept C110201527 @default.
- W1650347188 hasConcept C134018914 @default.
- W1650347188 hasConcept C140793950 @default.
- W1650347188 hasConcept C144024400 @default.
- W1650347188 hasConcept C149923435 @default.
- W1650347188 hasConcept C153026981 @default.
- W1650347188 hasConcept C188382862 @default.
- W1650347188 hasConcept C18903297 @default.
- W1650347188 hasConcept C193230392 @default.
- W1650347188 hasConcept C2780181586 @default.
- W1650347188 hasConcept C2908647359 @default.
- W1650347188 hasConcept C2992768293 @default.
- W1650347188 hasConcept C55493867 @default.
- W1650347188 hasConcept C72958200 @default.
- W1650347188 hasConcept C77077793 @default.
- W1650347188 hasConcept C86803240 @default.
- W1650347188 hasConcept C90856448 @default.
- W1650347188 hasConcept C96857902 @default.
- W1650347188 hasConceptScore W1650347188C109931610 @default.
- W1650347188 hasConceptScore W1650347188C110201527 @default.
- W1650347188 hasConceptScore W1650347188C134018914 @default.
- W1650347188 hasConceptScore W1650347188C140793950 @default.
- W1650347188 hasConceptScore W1650347188C144024400 @default.
- W1650347188 hasConceptScore W1650347188C149923435 @default.
- W1650347188 hasConceptScore W1650347188C153026981 @default.
- W1650347188 hasConceptScore W1650347188C188382862 @default.
- W1650347188 hasConceptScore W1650347188C18903297 @default.
- W1650347188 hasConceptScore W1650347188C193230392 @default.
- W1650347188 hasConceptScore W1650347188C2780181586 @default.
- W1650347188 hasConceptScore W1650347188C2908647359 @default.
- W1650347188 hasConceptScore W1650347188C2992768293 @default.
- W1650347188 hasConceptScore W1650347188C55493867 @default.
- W1650347188 hasConceptScore W1650347188C72958200 @default.
- W1650347188 hasConceptScore W1650347188C77077793 @default.
- W1650347188 hasConceptScore W1650347188C86803240 @default.
- W1650347188 hasConceptScore W1650347188C90856448 @default.
- W1650347188 hasConceptScore W1650347188C96857902 @default.
- W1650347188 hasLocation W16503471881 @default.
- W1650347188 hasOpenAccess W1650347188 @default.
- W1650347188 hasPrimaryLocation W16503471881 @default.
- W1650347188 hasRelatedWork W2001549262 @default.
- W1650347188 hasRelatedWork W2072599802 @default.
- W1650347188 hasRelatedWork W2140177738 @default.
- W1650347188 hasRelatedWork W2148544556 @default.
- W1650347188 hasRelatedWork W2158557529 @default.
- W1650347188 hasRelatedWork W2167736788 @default.
- W1650347188 hasRelatedWork W2275479214 @default.
- W1650347188 hasRelatedWork W2530387770 @default.
- W1650347188 hasRelatedWork W2537592805 @default.
- W1650347188 hasRelatedWork W2560704802 @default.
- W1650347188 hasRelatedWork W2589704486 @default.
- W1650347188 hasRelatedWork W2610194588 @default.
- W1650347188 hasRelatedWork W2616031531 @default.
- W1650347188 hasRelatedWork W2772143593 @default.
- W1650347188 hasRelatedWork W2783554638 @default.
- W1650347188 hasRelatedWork W2884378001 @default.
- W1650347188 hasRelatedWork W2896913088 @default.
- W1650347188 hasRelatedWork W3006126791 @default.
- W1650347188 hasRelatedWork W3091903505 @default.
- W1650347188 hasRelatedWork W3123692868 @default.
- W1650347188 isParatext "false" @default.
- W1650347188 isRetracted "false" @default.
- W1650347188 magId "1650347188" @default.
- W1650347188 workType "dissertation" @default.