The ecology of Ramalina menziesii. V. Estimation of gross carbon gain and thallus hydration source from diurnal measurements and climatic data

1986 ◽  
Vol 64 (8) ◽  
pp. 1698-1702 ◽  
Author(s):  
U. Matthes-Sears ◽  
T. H. Nash III
Keyword(s):  
Carbon Fixation ◽  
Daily Precipitation ◽  
Dry Weight ◽  
Predictor Variables ◽  
Carbon Gain ◽  
Climatic Data ◽  
Atmospheric Water ◽  
Annual Carbon ◽  
Total Gain ◽  
Calculated Average

All subsets regression analysis was used to determine the set of meteorological variables that best predicted daily gross carbon fixation of the lichen Ramalina menziesii Tayl. measured on 23 days at Hastings Reservation in central coastal California. The regression equation containing the two best predictor variables, the duration of diurnal atmospheric humidities equal to or above 90% and daily precipitation, was then used in conjunction with weather records to estimate daily, seasonal, and annual gross CO2 gain of R. menziesii at Hastings for the years 1981 – 1983. Calculated average annual gross CO2 fixation for these 3 years was 2756 mg CO2∙g dry weight−1. For 66% of this total gain, the most likely source of thallus hydration was rainfall. Dewfall was responsible for 15%, atmospheric water vapor uptake for 11%, and for the remaining 8% the source was uncertain. Three-fourths of the annual carbon fixation took place during the 6 months of the rainy season.

Lichen carbon gain under tropical conditions: water relations and CO2 exchange of Lobariaceae species of a lower montane rainforest in Panama

2004 ◽  
Vol 36 (5) ◽  
pp. 329-342 ◽  
Author(s):  
Otto L. LANGE ◽  
Burkhard BÜDEL ◽  
Angelika MEYER ◽  
Hans ZELLNER ◽  
Gerhard ZOTZ
Keyword(s):  
Water Relations ◽  
Carbon Fixation ◽  
Nitrogen Concentration ◽  
Carbon Gain ◽  
Carbon Loss ◽  
Natural Conditions ◽  
Low Light ◽  
Green Algal ◽  
Tropical Conditions ◽  
Montane Rainforest

Diel (24-h) time courses of microclimate, water relations, and CO2 exchange were measured under quasi-natural conditions at a forest edge in a lower montane, tropical rainforest in Panama for six Lobariaceae (Lobaria crenulata, L. dissecta, Pseudocyphellaria aurata, P. intricata, Sticta sublimbata, S. weigelii). Responses to experimentally controlled water content (WC), photosynthetic photon fluence rate (PPFR), and temperature were studied in most detail with P. aurata.Photosynthesis was well adapted to high temperatures, and all species exhibited ‘shade plant’ characteristics with low light compensation points and low light saturation. Lobaria and Pseudocyphellaria species suffered from a strong depression of net photosynthesis (NP) at suprasaturating WC; suprasaturation depression was less in cyphellate Sticta species.Photosynthetic capacity correlated with thallus nitrogen concentration, and maximal NP rates of the cyanobacterial Sticta species was 4 to 5 times higher than that of the green algal Lobaria species. However, high rates of NP were uncommon and brief events under natural conditions; the different environmental factors were rarely optimal simultaneously. Similar to earlier observations with other rainforest lichens, NP ceased during the period of highest irradiation on most days due to desiccation. During moist periods low light often limited carbon fixation, and high thallus hydration was often detrimental to NP. In spite of these limitations the maximal daily integrated net photosynthetic carbon income (ΣNP) was quite high especially for the Sticta species [17·3 and 24·1 mgC (gC)−1 day−1 for S. sublimbata and S. weigelii, respectively]. High nocturnal carbon loss, due to high night temperatures and continuous hydration, resulted in frequent negative diel carbon balances (ΣC) in all species. The average nocturnal carbon loss amounted to 83 and 70% ΣNP for P. aurata and P. intricata, respectively and to 64 and 59% of ΣNP for S. sublimbata and S. weigelii, respectively. Their average diel ΣC was as high as 3·7 and 5·3 mgC (gC)−1 day−1. In contrast, ΣC was much lower for the other species, it amounted to only 0·18 mgC (gC)−1 day−1 for L. crenulata. Thus, the Sticta species stood out amongst the species studied for their most successful adaptation of photosynthetic productivity to the habitat conditions in the lower montane rainforest.

Annual carbon fixation in terrestrial populations of Nostoc commune (Cyanobacteria) from an Antarctic dry valley is driven by temperature regime

2007 ◽  
Vol 13 (6) ◽  
pp. 1224-1237 ◽  
Author(s):  
PHIL M. NOVIS ◽  
DAVID WHITEHEAD ◽  
ED G. GREGORICH ◽  
JOHN E. HUNT ◽  
ASHLEY D. SPARROW ◽  
...  
Keyword(s):  
Temperature Regime ◽  
Carbon Fixation ◽  
Nostoc Commune ◽  
Dry Valley ◽  
Annual Carbon

scholarly journals The role of retrospective weather forecasts in developing daily forecasts of nutrient loadings over the southeast US

2014 ◽  
Vol 18 (8) ◽  
pp. 2885-2898
Author(s):  
J. Oh ◽  
T. Sinha ◽  
A. Sankarasubramanian
Keyword(s):  
Water Quality ◽  
Real Time ◽  
Daily Precipitation ◽  
Coefficient Of Determination ◽  
Climatic Data ◽  
Weather Forecasts ◽  
Nutrient Loadings ◽  
Daily Streamflow ◽  
Streamflow Forecasts ◽  
Southeast Us

Abstract. It is well known in the hydrometeorology literature that developing real-time daily streamflow forecasts in a given season significantly depends on the skill of daily precipitation forecasts over the watershed. Similarly, it is widely known that streamflow is the most important predictor in estimating nutrient loadings and the associated concentration. The intent of this study is to bridge these two findings so that daily nutrient loadings and the associated concentration could be predicted using daily precipitation forecasts and previously observed streamflow as surrogates of antecedent land surface conditions. By selecting 18 relatively undeveloped basins in the southeast US (SEUS), we evaluate the skill in predicting observed total nitrogen (TN) loadings in the Water Quality Network (WQN) by first developing the daily streamflow forecasts using the retrospective weather forecasts based on K-nearest neighbor (K-NN) resampling approach and then forcing the forecasted streamflow with a nutrient load estimation (LOADEST) model to obtain daily TN forecasts. Skill in developing forecasts of streamflow, TN loadings and the associated concentration were computed using rank correlation and RMSE (root mean square error), by comparing the respective forecast values with the WQN observations for the selected 18 Hydro-Climatic Data Network (HCDN) stations. The forecasted daily streamflow and TN loadings and their concentration have statistically significant skill in predicting the respective daily observations in the WQN database at all 18 stations over the SEUS. Only two stations showed statistically insignificant relationships in predicting the observed nitrogen concentration. We also found that the skill in predicting the observed TN loadings increases with the increase in drainage area, which indicates that the large-scale precipitation reforecasts correlate better with precipitation and streamflow over large watersheds. To overcome the limited samplings of TN in the WQN data, we extended the analyses by developing retrospective daily streamflow forecasts over the period 1979–2012 using reforecasts based on the K-NN resampling approach. Based on the coefficient of determination (R2Q-daily) of the daily streamflow forecasts, we computed the potential skill (R2TN-daily) in developing daily nutrient forecasts based on the R2 of the LOADEST model for each station. The analyses showed that the forecasting skills of TN loadings are relatively better in the winter and spring months, while skills are inferior during summer months. Despite these limitations, there is potential in utilizing the daily streamflow forecasts derived from real-time weather forecasts for developing daily nutrient forecasts, which could be employed for various adaptive nutrient management strategies for ensuring better water quality.

scholarly journals Growth Respiration, Maintenance Respiration, and Carbon Fixation of Vinca: A Time Series Analysis

2000 ◽  
Vol 125 (6) ◽  
pp. 702-706 ◽  
Author(s):  
Marc W. van Iersel ◽  
Lynne Seymour
Keyword(s):  
Carbon Balance ◽  
Carbon Fixation ◽  
Plant Size ◽  
Carbon Gain ◽  
Maintenance Respiration ◽  
Carbon Use Efficiency ◽  
Size Growth ◽  
Growth Respiration ◽  
Use Efficiency ◽  
Traditional Approaches

Respiration is important in the overall carbon balance of plants, and can be separated into growth (Rg) and maintenance respiration (Rm). Estimation of Rg and Rm throughout plant development is difficult with traditional approaches. Here, we describe a new method to determine ontogenic changes in Rg and Rm. The CO2 exchange rate of groups of 28 `Cooler Peppermint' vinca plants [Catharanthus roseus (L.) G. Don.] was measured at 20 min intervals for 2 weeks. These data were used to calculate daily carbon gain (DCG, a measure of growth rate) and cumulative carbon gain (CCG, a measure of plant size). Growth and maintenance respiration were estimated based on the assumption that they are functions of DCG and CCG, respectively. Results suggested a linear relationship between DCG and Rg. Initially, Rm was three times larger than Rg, but they were similar at the end of the experiment. The decrease in the fraction of total available carbohydrates that was used for Rm resulted in an increase in carbon use efficiency from 0.51 to 0.67 mol·mol-1 during the 2-week period. The glucose requirement of the plants was determined from Rg, DCG, and the carbon fraction of the plant material and estimated to be 1.39 g·g-1, while the maintenance coefficient was estimated to be 0.031 g·g-1·d-1 at the end of the experiment. These results are similar to values reported previously for other species. This suggests that the use of semicontinuous CO2 exchange measurements for estimating Rg and Rm yields reasonable results.

scholarly journals Light Effects on Wax Begonia: Photosynthesis, Growth Respiration, Maintenance Respiration, and Carbon Use Efficiency

2004 ◽  
Vol 129 (3) ◽  
pp. 416-424 ◽  
Author(s):  
Krishna S. Nemali ◽  
M.W. van Iersel
Keyword(s):  
Growth Period ◽  
Dry Weight ◽  
Carbon Gain ◽  
Maintenance Respiration ◽  
Gross Photosynthesis ◽  
Carbon Use Efficiency ◽  
Whole Plant ◽  
Growth Respiration ◽  
Use Efficiency ◽  
Gas Exchange System

The effect of increasing daily light integral (DLI; 5.3, 9.5, 14.4, and 19.4 mol·m-2·d-1) on photosynthesis and respiration of wax begonia (Begonia semperflorens-cultorum Hort.) was examined by measuring CO2 exchange rates (CER) for a period of 25 d in a whole-plant gas exchange system. Although plant growth rate (GR, increase in dry weight per day) increased linearly with increasing DLI, plants grown at low DLI (5.3 or 9.5 mol·m-2·d-1) respired more carbohydrates than were fixed in photosynthesis during the early growth period (13 and 4 d, respectively), resulting in a negative daily carbon gain (DCG) and GR. Carbon use efficiency [CUE, the ratio of carbon incorporated into the plant to C fixed in gross photosynthesis (Pg)] of plants grown at low DLI was low, since these plants used most of the C fixed in Pg for maintenance respiration (Rm), leaving few, if any, C for growth and growth respiration (Rg). Maintenance respiration accounted for a smaller fraction of the total respiration with increasing DLI. In addition, the importance of Rm in the carbon balance of the plants decreased over time, resulting in an increase in CUE. At harvest, crop dry weight (DWCROP) increased linearly with increasing DLI, due to the increased photosynthesis and CUE at high PPF.

scholarly journals Micropropagation, Decontamination, Transcontinental Shipping and Hydroponic Growth of Cattleya while Sealed in Semipermeable Membrane Vessels

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 547A-547 ◽  
Author(s):  
Jeffrey Adelberg ◽  
Robert Pollock ◽  
Nihal Rajapakse ◽  
Roy Young
Keyword(s):  
Carbon Fixation ◽  
Scale Up ◽  
Three Dimensional ◽  
Carbon Assimilation ◽  
Dry Weight ◽  
The United States ◽  
Hydroponic Culture ◽  
Permeable Membrane ◽  
Shoot Dry Weight ◽  
Carbohydrate Concentration

Two varieties of Cattleya orchids (C. Loddigessi `Elen' × C. Loddigessi Alba `Extra' and Brassolaeliocattleya. Mem. `Helen Brown' Sweet Afton) were micropropagated in sealed, three-dimensional polypropylene vessels with microporous, semi-permeable membrane films to allow diffusion of water, dissolved nutrients, and gas to plant material inside the vessels. During tissue culture on sugar-containing media, chance contaminants were eliminated on the vessels outer surface using 5% bleach solution. Proper decontamination treatment did not effect carbohydrate content or subsequent growth of tissues contained within the vessels. Plantlets remaining in membrane vessels were shipped (7 days at 14–30°C) from Japan to the United States in the dark in a plastic tray and arrived without changes in fresh or dry weight of whole plantlets. However, shoot dry weight did increase significantly. Sucrose, glucose, and fructose reserves established on sugar-containing media were greater in root than shoot tissue and were largely expended during shipping concurrent with increased shoot dry weight. It is likely carbohydrate catabolism provided energy for these CAM plantlets to continue carbon fixation, resulting in positive net carbon assimilation in the dark shipping environment. Changes in starch concentrations during shipping were not significant. Plantlets grew photoautotrophically in hydroponic culture in the greenhouse, following transport in the same sealed membrane vessels. Carbohydrate concentration of plantlets following hydroponic culture was not significantly different than after the shipping process. Sealed-membrane vessels for micropropagation, decontamination, shipping and greenhouse growth were useful for culture of Cattleya to facilitate scale-up of materials handling and international commerce of tissue-cultured plants.

scholarly journals The role of retrospective weather forecasts in developing daily forecasts of nutrient loadings over the Southeast US

2013 ◽  
Vol 10 (12) ◽  
pp. 15625-15657 ◽  
Author(s):  
J. Oh ◽  
T. Sinha ◽  
A. Sankarasubramanian
Keyword(s):  
Water Quality ◽  
Real Time ◽  
Daily Precipitation ◽  
Climatic Data ◽  
Weather Forecasts ◽  
Nutrient Loadings ◽  
Daily Streamflow ◽  
Increase With Increase ◽  
Streamflow Forecasts ◽  
Southeast Us

Abstract. It is well-known in the hydrometeorology literature that developing real-time daily streamflow forecasts in a given season significantly depend on the skill of daily precipitation forecasts over the watershed. Similarly, it is widely known that streamflow is the most important predictor in estimating nutrient loadings and the associated concentration. The intent of this study is to bridge these two findings so that daily nutrient loadings and the associated concentration could be predicted using daily precipitation forecasts and previously observed streamflow as surrogates of antecedent land surface conditions. By selecting 18 relatively undeveloped basins in the Southeast US (SEUS), we evaluate the skill in predicting observed total nitrogen (TN) loadings in the Water Quality Network (WQN) by first developing the daily streamflow forecasts using the retrospective weather forecasts based on K-nearest neighbor (K-NN) resampling approach and then forcing the forecasted streamflow with a nutrient load estimation (LOADEST) model to obtain daily TN forecasts. Skill in developing forecasts of streamflow, TN loadings and the associated concentration were computed using rank correlation and RMSE, by comparing the respective forecast values with the WQN observations for the selected 18 Hydro-Climatic Data Network (HCDN) stations. The forecasted daily streamflow and TN loadings and their concentration have statistically significant skill in predicting the respective daily observations in the WQN database at all the 18 stations over the SEUS. Only two stations showed statistically insignificant relationship in predicting the observed nitrogen concentration. We also found that the skill in predicting the observed TN loadings increase with increase in drainage area which indicates that the large-scale precipitation reforecasts correlate better with precipitation and streamflow over large watersheds. To overcome the limited samplings of TN in the WQN data, we extended the analyses by developing retrospective daily streamflow forecasts over the period 1979–2012 using reforecasts based on the K-NN resampling approach. Based on the coefficient of determination (RQ-daily2) of the daily streamflow forecasts, we computed the potential skill (RTN-daily2) in developing daily nutrient forecasts based on the R2 of the LOADEST model for each station. The analyses showed that the forecasting skills of TN loadings are relatively better in winter and spring months while skills are inferior during summer months. Despite these limitations, there is potential in utilizing the daily streamflow forecasts derived from real-time weather forecasts for developing daily nutrient forecasts, which could be employed for various adaptive nutrient management strategies for ensuring better water quality.

Growth Analysis of the Effect of Phosphorus Nutrition on Seedings of Eucalyptus grandis

1992 ◽  
Vol 19 (1) ◽  
pp. 55 ◽  
Author(s):  
MUF Kirschbaum ◽  
DW Bellingham ◽  
RN Cromer
Keyword(s):  
Leaf Area ◽  
Specific Leaf Area ◽  
Carbon Fixation ◽  
Eucalyptus Grandis ◽  
Dry Weight ◽  
Plant Size ◽  
Phosphorus Concentration ◽  
Fixation Rate ◽  
Unit Leaf ◽  
Addition Rate

Eucalyptus grandis seedlings were grown in growth units in which plant roots were suspended in air while continuously being sprayed with nutrient solution (aeroponic system). Phosphorus was added to nutrient solutions in exponentially increasing amounts which determined plant growth. Phosphorus was added at five different relative addition rates. The proportion of dry matter in stems increased with plant size, but was independent of plant internal phosphorus concentration. In contrast, the ratio of root to leaf dry weight decreased almost 2-fold with increasing phosphorus concentration but changed little with plant size, and specific leaf area more than doubled with increasing phosphorus concentration. Carbon fixation rate per unit plant dry weight increased about 5-fold with increasing nutrient addition rate over the range of addition rates used. That increase was due to a doubling in specific leaf area and a doubling in assimilation rate per unit leaf area, while leaf weight as a fraction of total plant dry weight increased by about 20%.

Extracellular production in relation to growth of four planktonic algae and of phytoplankton populations from Lake Ontario

1969 ◽  
Vol 47 (3) ◽  
pp. 405-413 ◽  
Author(s):  
C. Nalewajko ◽  
L. Marin
Keyword(s):  
Growth Rate ◽  
Environmental Factors ◽  
Carbon Fixation ◽  
Natural Populations ◽  
Lake Ontario ◽  
Dry Weight ◽  
Weight Basis ◽  
Extracellular Production ◽  
Relative Growth ◽  
Planktonic Algae

In four species of planktonic algae both carbon fixation and excretion on an ash-free dry weight basis increase with relative growth rate (K) of the culture measured in log10 units. In natural populations percentage excretion values are positively correlated with K values; however, environmental factors may be of relatively greater importance and determine the extent of excretion.

scholarly journals Boosting Autofermentation Rates and Product Yields with Sodium Stress Cycling: Application to Production of Renewable Fuels by Cyanobacteria

2010 ◽  
Vol 76 (19) ◽  
pp. 6455-6462 ◽  
Author(s):  
Damian Carrieri ◽  
Dariya Momot ◽  
Ian A. Brasg ◽  
Gennady Ananyev ◽  
Oliver Lenz ◽  
...  
Keyword(s):  
Carbon Fixation ◽  
Dry Weight ◽  
Sodium Concentration ◽  
Soluble Carbohydrates ◽  
Acetyl Coa ◽  
Product Yields ◽  
Carbonate Buffer ◽  
New Strategy ◽  
Storage Products ◽  
Stress Cycling

ABSTRACT Sodium concentration cycling was examined as a new strategy for redistributing carbon storage products and increasing autofermentative product yields following photosynthetic carbon fixation in the cyanobacterium Arthrospira (Spirulina) maxima. The salt-tolerant hypercarbonate strain CS-328 was grown in a medium containing 0.24 to 1.24 M sodium, resulting in increased biosynthesis of soluble carbohydrates to up to 50% of the dry weight at 1.24 M sodium. Hypoionic stress during dark anaerobic metabolism (autofermentation) was induced by resuspending filaments in low-sodium (bi)carbonate buffer (0.21 M), which resulted in accelerated autofermentation rates. For cells grown in 1.24 M NaCl, the fermentative yields of acetate, ethanol, and formate increase substantially to 1.56, 0.75, and 1.54 mmol/(g [dry weight] of cells·day), respectively (36-, 121-, and 6-fold increases in rates relative to cells grown in 0.24 M NaCl). Catabolism of endogenous carbohydrate increased by approximately 2-fold upon hypoionic stress. For cultures grown at all salt concentrations, hydrogen was produced, but its yield did not correlate with increased catabolism of soluble carbohydrates. Instead, ethanol excretion becomes a preferred route for fermentative NADH reoxidation, together with intracellular accumulation of reduced products of acetyl coenzyme A (acetyl-CoA) formation when cells are hypoionically stressed. In the absence of hypoionic stress, hydrogen production is a major beneficial pathway for NAD+ regeneration without wasting carbon intermediates such as ethanol derived from acetyl-CoA. This switch presumably improves the overall cellular economy by retaining carbon within the cell until aerobic conditions return and the acetyl unit can be used for biosynthesis or oxidized via respiration for a much greater energy return.

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