Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 37 for “"gross primary production"”.
-
Ground vegetation gross primary production dynamics of a drained peatland forest ecosystem
… atmosphere. Thus, to explore ground vegetation gross primary production (GPPGV) dynamics, its affecting factors, and impacts of the partial harvest; forest floor net exchange (NEFF) and respiration (RFF) were measured on an hourly interval with an automated closed flux chamber method were …
-
Remote sensing-based assessment of Gross Primary Production (GPP) in agricultural ecosystems
… form of food products, e.g. agricultural yield. Gross primary production (GPP) of agricultural ecosystems is the amount of total carbon assimilated by the planted crops and the driver of useful biomass production. To assess the GPP of croplands, this study combines information from flux …
-
A joint analysis of gross primary production and evapotranspiration of Australia using eddy covariance, remote sensing and land surface modelling approaches
… aim of this thesis is to analyze the patterns of gross primary production (GPP) and evapotranspiration (ET) across Australian biomes in combination of eddy covariance, remote sensing and land surface model (LSM) methods, taking advantage of their respective applicability on different space and …
-
Aapasuon kasvillisuus ja sen vaikutus hiilidioksidin vaihtoon
… plants, Sphagnum mosses had a much lower gross photosynthetic capacity. Plant communities on lawns and hummocks with an abundancy of sedges (Cyperaceae) had a higher gross photosynthetic capacity and respiration level than plant communities in hollows. Factors leading to increased …
-
Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers
… and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, …
-
Insight into chemical, biological, and physical processes in coastal waters from dissolved oxygen and inert gas tracers
… and triple isotopic composition trace net and gross biological productivity. The saturation states of inert gases trace physical processes, such as air-water gas exchange, temperature change, and mixing, that affect all gases. First, I developed a field-deployable system that measures Ne, Ar, …
-
The Effect of Elevated Carbon Dioxide and Ozone on Soybean Development, Leaf Anatomy and Productivity
… increase in canopy photosynthesis or gross primary production (GPP). A draw-back of FACE is that GPP cannot be measured directly. Measurements of micrometeorology, leaf photosynthetic properties and canopy structure were combined in an adapted version of the Integrated Scientific …
-
The Role of Autochothnous Production in the Formation of Dissolved and Particulate Organics in Laboratory Streams
The role of autochthonous production in the formation of dissolved and fine particulate organic carbon (DOC and FPOC) was studied in simplified communities in six laboratory streams. Production of DOC and FPOC by laboratory stream communities exposed to low (170 ft-c), intermediate (260 ft-c), and …
-
Uncertainty quantification and calibration of physical models
… and underlying parameters, and the outputs are gross primary production (GPP), net ecosystem production (NEP) and other variables. To make predictions of future outputs from the computer model, I also estimate the under- lying parameters. With an efficient Bayesian approximation, statistical …
-
Seasonal Variation in Whole Stream Metabolism across Varying Land Use Types
… from 2010-2011. I used these data to estimate gross primary production (GPP) and ecosystem respiration (ER). GPP and ER were compared to stream chemistry, light, land cover, and storms. I found that there is greater influence of local riparian land cover than watershed land cover on GPP and ER. …
-
Stress-induced alterations in ecosystem function: the role of acidification in lotic metabolism and biogeochemistry
… biomass, possibly related to increased exoenzyme production as part of the stress response. Whole-stream ¹⁵N experiments and measurements of respiration and fungal standing crop across the pH gradient resulted in similar patterns in <i>q</i>CO₂ and <i>q</i>N found in microcosm experiments, …
-
Evaluation and Application of the Community Land Model for Simulating Energy and Carbon Exchange in Agricultural Ecosystems
… parameters was developed to better simulate crop gross primary production (GPP), ecosystem respiration (ER) and leaf area index (LAI). The key parameters include the maximum carboxylation rate at 25 oC (Vcmax25), specific leaf area at the top of the canopy (slatop) and a parameter determining the …
-
Ecosystem metabolism in coastal plain streams of southeast Louisiana : environmental and watershed effects
… light, nutrients, and stable substrates for gross primary production (GPP) and a source of organic matter (OM) for ecosystem respiration (ER). Stream size is important at mediating these factors through the presence or absence of a riparian canopy where small streams tend to have an intact …
-
Evaluating the role of flow and specific conductivity on stream metabolism across a mining-induced salinity gradient in the Appalachian Coalfield
… stream metabolism. Understanding how gross primary production (GPP) and ecosystem respiration (ER) respond to salinity, stream flow, and their association is needed to characterize the consequences of salinization on stream processes. To assess the role of salinization and discharge on …
-
Solar-induced chlorophyll fluorescence (SIF) as a proxy of canopy photosynthesis for crops in the U.S. corn belt
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2024-12-01
-
Mesoscale Wind and Temperature Changes over Peatlands of the Hudson Bay Lowlands: impacts on the Surface Energy Balance and Net CO2 Exchange
… warming and permafrost carbon feedback. The primary aim of this study is to improve our understanding of the warming-induced changes in the advective influence of the Hudson Bay and its linkage to the changes in the surface energy and carbon balance over peatlands of the HBL. I use a combined …
-
Recent changes in land use and productivity in agro-pastoral Inner Mongolia, China
… means to buy them as more critical for crop production than soil erosion. This indicates the increase in use of and dependence on agro-chemicals, a trend confirmed by regional statistics, and concern is raised regarding the sustainability of the rapid agricultural development. The …
-
Recovery of southern Appalachian streams from historical agriculture
… Agricultural streams had higher rates of gross primary production (GPP) and GPP to respiration (P/R) ratios than forested streams, indicating that agriculture enhances autotrophic metabolism in streams. Agriculture did not have a significant effect on wood breakdown or microbial biofilm …
-
Canopy structural and meteorological influences on CO2 exchange for MODIS product validation in a boreal jack pine chronosequence
… Finally, the fourth objective was to model gross primary production (GPP) from airborne lidar. Lidar estimates of GPP were then compared with those from the EC system at the jack pine chronosequence and with the MODIS GPP (Collection 5) product.
-
Modelling Stream Metabolism and Fish Biomass in Headwater Streams of the Eastern Cascades Mountains
… relationship from a previously published study. Gross primary production across sites and sampling periods ranged from 0.01 to 0.71 g O<sub>2</sub> m<sup>-2</sup> d<sup>-1</sup>, varied by sampling period, and increased with stream depth. Ecosystem respiration ranged from 4.55 to 24.29 g …
Page 1 of 2