Temporal changes in nitrogen and phosphorus codeficiency of plankton in lakes of coastal and interior British Columbia

2004 ◽  
Vol 61 (8) ◽  
pp. 1538-1551 ◽  
Author(s):  
John-Mark Davies ◽  
Weston H Nowlin ◽  
Asit Mazumder
Keyword(s):  
British Columbia ◽  
Nutrient Limitation ◽  
Size Fraction ◽  
Nutrient Deficiency ◽  
Physiological Status ◽  
Nutrient Deficiencies ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Lakes And Reservoirs ◽  
Plankton Communities

Plankton nutrient limitation and deficiency were assessed in six coastal and four interior lakes and reservoirs in British Columbia. Ultimate nutrient limitation was defined as occurring over longer time scales (months to years) and represented the potential attainable biomass or yield. Proximate nutrient deficiency reflected plankton physiological status and, therefore, represented potential limitations of instantaneous growth rates. All lakes and reservoirs were considered to be ultimately P-limited according to total N to total P ratios (TN:TP). However, both P and N deficiencies were found to occur at the same time, suggesting that when deficiency occurs, codeficiency is common. The <3 µm size fraction accounted for a large proportion of P debt, whereas the >3 µm size fraction accounted for most of the ammonium-enhanced response. Thus, plankton size is important for understanding nutrient deficiencies in plankton communities. Our results stress (i) the importance of measuring proximate deficiencies at greater temporal resolution, (ii) that N and P were commonly found to be codeficient, (iii) the need to define nutrient limitation and deficiency in the context of the method used, and (iv) that several concurrent measures of deficiency are required to assess the nutrient status of plankton communities.

Bacterioplankton, Phytoplankton, and Zooplankton Communities in a British Columbia Coastal Lake Before and After Nutrient Reduction

1986 ◽  
Vol 43 (8) ◽  
pp. 1504-1514 ◽  
Author(s):  
F. Joan Hardy ◽  
Ken S. Shortreed ◽  
John G. Stockner
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Inorganic Nitrogen ◽  
Size Fraction ◽  
Growing Season ◽  
Nutrient Reduction ◽  
Nitrogen And Phosphorus ◽  
Coastal Lake ◽  
Before And After ◽  
High Concentrations

Inorganic nitrogen and phosphorus were applied weekly during the growing season from 1980 to 1982 and twice weekly in 1983 to Hobiton Lake, a warm monomictic coastal lake in British Columbia. The lake was not fertilized in 1984. Average numbers of bacteria during the growing season decreased from a high of 1.53 × 106∙mL−1 in the fertilized condition to 0.84 × 106∙mL−1 in the unfertilized condition. Chlorophyll a concentrations decreased from a maximum seasonal average of 2.69 μg∙L−1 (1981) to 1.30 μg∙L−1 (1984), and algal numbers decreased from 5.83 × 104∙mL−1 (1983) to 2.29 × 104∙mL−1 (1984). Although the numbers of phytoplankton in each size fraction (picoplankton, nanoplankton, or microplankton) decreased in the unfertilized condition, the greatest change was an almost fourfold decrease in picoplankton, which consisted of 90% cyanobacteria (primarily Synechococcus spp.). Abundance of the large diatoms Rhizosolenia spp. and Melosira spp. increased in 1984, resulting in an increase in average seasonal algal volume. Average densities of medium (0.15–0.84 mm) and large (0.85–1.5 mm) zooplankton were greatest in 1982, while rotifers and small zooplankton (0.10–0.14 mm) were most dense in 1984 following nutrient reduction. The lake had relatively high concentrations of planktivorous juvenile sockeye salmon (Oncorhynchus nerka) that appeared to minimize any direct effect of nutrient additions on zooplankton densities.

scholarly journals Metabolic response of Botryococcus braunii to high bicarbonate dosages and other conditions: analysis of photosynthetic performance, productivity, and lipidomic profile

2021 ◽  
Author(s):  
Néstor David Giraldo ◽  
Sandra Marcela Correa ◽  
Andrés Arbeláez ◽  
Felix L. Figueroa ◽  
Rigoberto Ríos-Estepa ◽  
...  
Keyword(s):  
Nutrient Limitation ◽  
Metabolic Response ◽  
Neutral Lipids ◽  
Biomass Productivity ◽  
Botryococcus Braunii ◽  
Photosynthetic Performance ◽  
Lipid Productivity ◽  
Cellular Growth ◽  
Adaptive Responses ◽  
Nitrogen And Phosphorus

AbstractIn this study the metabolic responses of Botryococcus braunii were analyzed upon different inorganic carbon dosages and nutrient limitation conditions in terms of lipid and biomass productivity, as well as photosynthetic performance. The nutritional schemes evaluated included different levels of sodium bicarbonate and nitrogen and phosphorus starvation, which were contrasted against standard cultures fed with CO2. Bicarbonate was found to be an advantageous carbon source since high dosages caused a significant increase in biomass and lipid productivity, in addition to an enhanced photosynthetic quantum yield and neutral lipids abundance. This contrasts to the commonly used approach of microalgae nutrient limitation, which leads to high lipid accumulation at the expense of impaired cellular growth, causing a decline in overall lipid productivity. The lipidome analysis served to hypothesize about the influence of the nutritional context on B. braunii structural and storage lipid metabolism, besides the adaptive responses exhibited by cells that underwent nutrient stress.

scholarly journals Evidence of Phosphate Mining and Agriculture Influence on Concentrations, Forms, and Ratios of Nitrogen and Phosphorus in a Florida River

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1064
Author(s):  
Shuiwang Duan ◽  
Kamaljit Banger ◽  
Gurpal S. Toor
Keyword(s):  
Agricultural Land ◽  
Water Discharge ◽  
Mining Area ◽  
Specific Conductance ◽  
Organic N ◽  
Wet Season ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Phosphate Mining ◽  
Molar Ratios

Florida has a long history of phosphate-mining, but less is known about how mining affects nutrient exports to coastal waters. Here, we investigated the transport of inorganic and organic forms of nitrogen (N) and phosphorus (P) over 23 sampling events during a wet season (June–September) in primary tributaries and mainstem of Alafia River that drains into the Tampa Bay Estuary. Results showed that a tributary draining the largest phosphate-mining area (South Prong) had less flashy peaks, and nutrients were more evenly exported relative to an adjacent tributary (North Prong), highlighting the effectiveness of the mining reclamation on stream hydrology. Tributaries draining > 10% phosphate-mining area had significantly higher specific conductance (SC), pH, dissolved reactive P (DRP), and total P (TP) than tributaries without phosphate-mining. Further, mean SC, pH, and particulate reactive P were positively correlated with the percent phosphate-mining area. As phosphate-mining occurred in the upper part of the watershed, the SC, pH, DRP, and TP concentrations increased downstream along the mainstem. For example, the upper watershed contributed 91% of TP compared to 59% water discharge to the Alafia River. In contrast to P, the highest concentrations of total N (TN), especially nitrate + nitrite (NOx–N) occurred in agricultural tributaries, where the mean NOx–N was positively correlated with the percent agricultural land. Dissolved organic N was dominant in all streamwaters and showed minor variability across sites. As a result of N depletion and P enrichment, the phosphate-mining tributaries had significantly lower molar ratios of TN:TP and NOx–N:DRP than other tributaries. Bi-weekly monitoring data showed consistent increases in SC and DRP and a decrease in NOx–N at the South Prong tributary (highest phosphate-mining area) throughout the wet season, and different responses of dissolved inorganic nutrients (negative) and particulate nutrients (positive) to water discharge. We conclude that (1) watersheds with active and reclaimed phosphate-mining and agriculture lands are important sources of streamwater P and N, respectively, and (2) elevated P inputs from the phosphate-mining areas altered the N:P ratios in streamwaters of the Alafia River.

scholarly journals Diurnal and spatial (vertical) dynamics of nutrients (N, P, Si) in four sampling days (summer, fall, winter, and spring) in a tropical shallow reservoir and their relationships with the phytoplankton community

2005 ◽  
Vol 65 (1) ◽  
pp. 141-157 ◽  
Author(s):  
J. J. Ramírez ◽  
C. E. M. Bicudo
Keyword(s):  
Phytoplankton Community ◽  
Southeastern Brazil ◽  
Nitrogen And Phosphorus ◽  
Vertical Variation ◽  
Total N ◽  
Phosphorus Forms ◽  
Reactive Silica ◽  
Photosynthetic Assimilation ◽  
The City ◽  
Total P

The vertical and diurnal variation of nitrogen and phosphorus forms, as well as that of soluble reactive silica (SRS), were studied in four sampling days at Garças reservoir, a shallow tropical one located in the city of São Paulo, in southeastern Brazil. Except for N-NH4, all other inorganic forms of nitrogen (N-NO2, N-NO3, and total N) demonstrated decreased concentrations toward the bottom of reservoir. Similarly, all showed significant diurnal differences on every sampling day, with increased values during the night due to absence of photosynthetic assimilation during that period. In the sampling days, these forms decreased on the spring sampling day due to the bloom of Microcystis registered during this period of the year. All three forms of phosphorus (SRP, particulate P, and total P) showed significant vertical variation, except on the fall sampling day. On the summer sampling day there was an increase of both total P and particulate P, the latter because it constitutes more than 70% of the total P during all sampling days. Hourly phosphorus variation was significant during all sampling days, except for the summer one. The SRS vertical variation was significant during all sampling days, except for that in the spring. It was also different hourly on sampling days.

scholarly journals High Prevalence of Vitamin D Inadequacy During Late Postpartum in Canadian Mothers

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 790-790
Author(s):  
Sarah Montgomery ◽  
Angella Lee ◽  
Nasime Sarbar ◽  
Deborah Zibrik ◽  
Yvonne Lamers
Keyword(s):  
Vitamin D ◽  
British Columbia ◽  
Dietary Intake ◽  
Dietary Vitamin ◽  
Nutrient Deficiencies ◽  
Cross Sectional ◽  
Convenience Sample ◽  
Vitamin D Intake ◽  
Pregnancy And Postpartum ◽  
Dietary Vitamin D

Abstract Objectives To assess maternal dietary intake and adequacy at postpartum and to determine whether lifestyle characteristics and breastfeeding status are related to nutrient intakes. Methods We analyzed cross-sectional data from a convenience sample of 129 mothers at 18-mo postpartum, whose families were enrolled into a randomized toddler intervention trial, in the Lower Mainland, British Columbia, Canada. The Canadian Diet History Questionnaire II (C-DHQ II) was used to estimate usual dietary intake in the mothers during the preceding 12 months (i.e., between 6- to 18-mo postpartum). Implausible energy intakes were defined as &lt;600 kcal/day or &gt;3500 kcals/day, and excluded from analysis. Demographic and lifestyle characteristic data about the pregnancy and postpartum time period were collected using a questionnaire. Results Maternal mean (SD) age at birth was 33.5 (4.0) years and most women were of European (46%) or Asian (38%) ethnicity, and had Bachelor's degree or higher education (70%). About 75%, 88%, and 89% did not meet their dietary requirements (i.e., intake below the EAR) for fiber, potassium, and vitamin D intakes, from food only, respectively. Considering total dietary intake from food and supplements, the prevalence of dietary vitamin D inadequacy was 25%. Women of European ethnicity had higher vitamin D intake (median (IQR) in mg/1000kcal/day: 19.5 (7.26,101)) compared to Asian women (10.8 (3.87, 21.1); P &lt; 0.05). Dietary vitamin D intake was higher in breastfeeding (i.e., providing breastmilk as primary milk source, i.e., ³2 times/day, to their 18-mo old toddlers) compared to non- or occasionally breastfeeding mothers (20.0 (10.5, 61.1) versus 14.9 (4.28, 26.7) mg/1000kcal/day; P &lt; 0.05). Conclusions While most Canadian mothers in this sample met the EARs for most nutrients, the prevalence of dietary inadequacy was very high for vitamin D, potassium, and fiber. Some population groups may be especially at risk of developing nutrient deficiencies in this period of life characterized by postpartum recovery and transition; targeted public health strategies may be needed to address these deficiencies. Funding Sources This study is supported by The University of British Columbia, and the British Columbia Children's Hospital Research Institute, Canada, and is funded by Société des Produits Nestlé S.A.

scholarly journals Distribution of Triarrhena lutarioriparia and its reserve characteristics of nitrogen and phosphorus in Dongting Lake

2021 ◽  
Vol 237 ◽  
pp. 01004
Author(s):  
Youze Xu ◽  
Guangyi Fu ◽  
Nan Tang ◽  
Zhonghao He ◽  
Lincheng Jian ◽  
...  
Keyword(s):  
Scientific Basis ◽  
Dongting Lake ◽  
Lake Basin ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Remote Sensing Interpretation ◽  
Storage Characteristics ◽  
Total P ◽  
Lake Wetlands

Triarrhena lutarioriparia, a typical and most abundant macrophyte in Dongting lake wetland, was in the state of abandonment following the papermaking industry revocation in the lake basin. In order to provide scientific basis for precise management of T. lutarioriparia, the T. lutarioriparia distribution charateristics in Dongting Lake and its storage characteristics of nutrients were investigated in this study. Remote sensing interpretation results showed that the total area of T. lutarioriparia in Dongting Lake wetland was 58, 450 ha, 48.31% of which distributed in South Doting Lake wetlands. The nutrients contents were significantly different in T. lutarioriparia tissues, ranking in the descending order of spikes (TN 27.90 mg/g, TP 3.46 mg/g)>leaves (TN 16.38 mg/g, TP 2.11 mg/g)>stems (TN 5.38 mg/g, TP 0.85 mg/g). The total P quantities in each T. lutarioriparia tissue were ranked in the order: stems (560.26 t)>leaves (396.52 t)>spikes (284.67 t), while the total N quantities were within the range of 2170.02-2801.3 t. It was estimated that about 7712.99 t of TN and 1241.45 t of TP were annually removed from Dongting Lake by reaping T. lutarioriparia. The nutrients stored in the dead tissues of T. lutarioriparia might possess non-negligible impact on the water quality of Doting Lake.

scholarly journals A Study of Factors Influencing Plant Growth by WSN Approach and Plant Nutrient Deficiency Classification in Tomato Using SVM

2021 ◽  
Vol 23 (06) ◽  
pp. 36-46
Author(s):  
Vrunda Kusanur ◽  
◽  
Veena S Chakravarthi ◽  
Keyword(s):  
Machine Learning ◽  
Plant Growth ◽  
Nutrient Deficiency ◽  
Learning Model ◽  
Plant Nutrients ◽  
Polynomial Kernel ◽  
Second Phase ◽  
Nutrient Deficiencies ◽  
Deficiency Symptoms ◽  
Machine Learning Model

Soil temperature and humidity straight away influence plant growth and the availability of plant nutrients. In this work, we carried out experiments to identify the relationship between climatic parameters and plant nutrients. When the relative humidity was very high, deficiency symptoms were shown on plant leaves and fruits. But, recognizing and managing these plant nutrients manually would become difficult. However, no much research has been done in this field. The main objective of this research was to propose a machine learning model to manage nutrient deficiencies in the plant. There were two main phases in the proposed research. In the first phase, the humidity, temperature, and soil moisture in the greenhouse environment were collected using WSN and the influence of these parameters on the growth of plants was studied. During experimentation, it was investigated that the transpiration rate decreased significantly and the macronutrient contents in the plant leave decreased when the humidity was 95%. In the second phase, a machine learning model was developed to identify and classify nutrient deficiency symptoms in a tomato plant. A total of 880 images were collected from Bingo images to form a dataset. Among all these images, 80% (704 images) of the dataset were used to train the machine learning model and 20% (176 images) of the dataset were used for testing the model performance. In this study, we selected K-means Clustering for key points detection and SVM for classification and prediction of nutrient stress in the plant. SVM using linear kernel performed better with the accuracy rates of 89.77 % as compared to SVM using a polynomial kernel.

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