scholarly journals Biologically Regulated Nutrient Supply Systems

2015 ◽  
pp. 293-321 ◽  
Author(s):  
Timothy R. Cavagnaro
Author(s):  
Takashi Kamo ◽  
Ryuichiro Nishi

It is recognized that links among forests, rivers and sea are important, because biological and fisheries production in the coastal zone is influenced by land-sea interaction. There are several nutrient supply systems in the coastal zone. River runoff, the most dominant nutrient supply system, has been evaluated by many previous studies. In addition, submarine groundwater discharge (SGD) has recently been considered as an important source of dissolved material to the coastal zone. For example, Johannes (1980) shows that SGD supplies several times as much nitrate volume as river runoff. However, the nutrient supply mechanisms in sandy beach ecosystem are not yet fully understood. Thus, it is necessary to quantitatively evaluate freshwater discharge and nutrient supply in a sandy beach ecosystem. This study reveals the estimated flow rate and volume of groundwater discharge in Fukiagehama, Kagoshima Prefecture, Japan.


2020 ◽  
Vol 85 ◽  
pp. 47-58
Author(s):  
Y Jiang ◽  
Y Liu

Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.


2019 ◽  
Vol 2 (3) ◽  
pp. 164-169
Author(s):  
Mohammed Faza ◽  
Maulahikmah Galinium ◽  
Matthias Guenther

An energy supply system consists of a system of power plants and transmission anddistribution systems that supply electrical energy. The present project is limited to the modellingof the generation system. Its objective is the design and implementation of a web-basedapplication for simulating energy supply systems using the Laravel framework. The projectfocuses on six modules representing geothermal energy, solar energy, biopower, hydropower,storage, and fossil-based energy that are allocated to satisfy a given power demand. It isexecuted as a time series modelling for an exemplary year with hourly resolution. Thedevelopment of the software is divided into four steps, which are the definition of the userrequirements, the system design (activity, use case, system architecture, and ERD), the softwaredevelopment, and the software testing (unit testing, functionality testing, validity testing, anduser acceptance testing). The software is successfully implemented. All the features of thesoftware work as intended. Also, the software goes through validity testing using three differentinput data, to make sure the software is accurate. The result of the testing is 100% accuracy withrespect to the underlying model that was implemented in an excel calculation.


2017 ◽  
Vol 4 (1) ◽  
pp. 41-52
Author(s):  
Dedy Loebis

This paper presents the results of work undertaken to develop and test contrasting data analysis approaches for the detection of bursts/leaks and other anomalies within wate r supply systems at district meter area (DMA)level. This was conducted for Yorkshire Water (YW) sample data sets from the Harrogate and Dales (H&D), Yorkshire, United Kingdom water supply network as part of Project NEPTUNE EP/E003192/1 ). A data analysissystem based on Kalman filtering and statistical approach has been developed. The system has been applied to the analysis of flow and pressure data. The system was proved for one dataset case and have shown the ability to detect anomalies in flow and pres sure patterns, by correlating with other information. It will be shown that the Kalman/statistical approach is a promising approach at detecting subtle changes and higher frequency features, it has the potential to identify precursor features and smaller l eaks and hence could be useful for monitoring the development of leaks, prior to a large volume burst event.


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