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Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza
Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza
IGC Proceedings (1993-2023)
The nitrogen effects on Hyparrhenia diplandra were studied. Plants were grown on nutrient solutions of variable concentrations in nitrogen. The supplied nitrogen increased tillering, leaf production, lamina area, total dry matter accumulation and total nitrogen accumulation in lamina. A detailed examination showed that the effect on tillering was the main cause of the differences observed in dry weights between different treatments. The nitrogen supply elongated significantly the lamina and nitrogen deficiency increased its thickness; but this was not enough to compensate the loss of weight in lower nitrogen treatment. The lamina area as well as nitrogen accumulation in the lamina …
Novel Analytical Approaches For The Study Of Energy And Nutrient Flow In Streams, Michelle Catherine Kelly
Novel Analytical Approaches For The Study Of Energy And Nutrient Flow In Streams, Michelle Catherine Kelly
Dissertations, Master's Theses and Master's Reports
This dissertation applied novel modeling, experimental and statistical approaches to overcome the challenges of measuring and analyzing energy and nutrient cycling in streams through 3 studies: (1) determining the predictors of respiration and denitrification in streams across the United States, (2) simultaneous estimation of denitrification and nitrogen (N) fixation rates, and (3) the impact of C lability metrics on the interpretation of C degradation in DOM incubation experiments. In the first study, I used predictive modeling approaches to show that respiration and denitrification were positively correlated across the landscape but were predicted by factors at different spatial scales. Denitrification rates …
Characterizing Dryland Ecosystems Using Remote Sensing And Dynamic Global Vegetation Modeling, Abdolhamid Dashtiahangar
Characterizing Dryland Ecosystems Using Remote Sensing And Dynamic Global Vegetation Modeling, Abdolhamid Dashtiahangar
Boise State University Theses and Dissertations
Drylands include all terrestrial regions where the production of crops, forage, wood and other ecosystem services are limited by water. These ecosystems cover approximately 40% of the earth terrestrial surface and accommodate more than 2 billion people (Millennium Ecosystem Assessment, 2005). Moreover, the interannual variability of the global carbon budget is strongly regulated by vegetation dynamics in drylands. Understanding the dynamics of such ecosystems is significant for assessing the potential for and impacts of natural or anthropogenic disturbances and mitigation planning, and a necessary step toward enhancing the economic and social well-being of dryland communities in a sustainable manner (Global …
Soil Carbon And Nitrogen Accumulation In A Forested Debris Flow Chronosequence, California, Judith K. Turk, Robert C. Graham
Soil Carbon And Nitrogen Accumulation In A Forested Debris Flow Chronosequence, California, Judith K. Turk, Robert C. Graham
Conservation and Survey Division
The role of forest soils in the biogeochemical cycling of C and N is most dynamic during the early stages of soil development. To define C and N trends that occur with soil development in a mixed coniferous forest, a chronosequence formed by debris flows was studied. The accumulation rates of total organic C (TOC) and total N (TN) were evaluated in soils on 10 debris flow deposits, ranging from depth, since this was the depth of the shallowest debris flows. Carbon was found to accumulate in the organic horizons at a rate of 26.5 g m−2 yr−1 …
Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak
Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak
United States Geological Survey: Staff Publications
Deep-water (307–697 m) antipatharian (black coral) specimens were collected from the southeastern continental slope of the United States and the north-central Gulf of Mexico. The sclerochronology of the specimens indicates that skeletal growth takes place by formation of concentric coeval layers. We used 210Pb to estimate radial growth rate of two specimens, and to establish that they were several centuries old. Bands were delaminated in KOH and analyzed for carbon and nitrogen stable isotopes. Carbon values ranged from _16.4‰ to _15.7‰; the oldest specimen displayed the largest range in values. Nitrogen values ranged from 7.7‰ to 8.6‰. …
Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen
Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen
MSU Graduate Theses
Construction and subsequent draining of reservoirs can have dramatic affects on the release of nutrients and sediments to waterways. This study describes how the temporary draining of a small reservoir for dam repair influences downstream water quality. The Valley Mill Reservoir has a surface area of 6.1 hectares and volume of 150,000 m3 when filled. Water chemistry monitoring and water sampling were performed at six sites during baseflow and ten sites during runoff events for one year. Water samples were analyzed for total nitrogen (TN), total phosphorous (TP), and total suspended sediment (TSS) concentrations. Results indicate that draining of Valley …