Food Chains and Webs: Interaction with Ecosystem

Author(s):  
Gurminder Singh Chahil ◽  
Harsimran Kaur Gill ◽  
Gaurav Goyal
Keyword(s):  
Author(s):  
Judith A. Murphy ◽  
Anthony Paparo ◽  
Richard Sparks

Fingernail clams (Muscu1ium transversum) are dominant bottom-dwelling animals in some waters of the midwest U.S. These organisms are key links in food chains leading from nutrients in water and mud to fish and ducks which are utilized by man. In the mid-1950’s, fingernail clams disappeared from a 100-mile section of the Illinois R., a tributary of the Mississippi R. Some factor(s) in the river and/or sediment currently prevent clams from recolonizing areas where they were formerly abundant. Recently, clams developed shell deformities and died without reproducing. The greatest mortality and highest incidence of shell deformities appeared in test chambers containing the highest proportion of river water to well water. The molluscan shell consists of CaCO3, and the tissue concerned in its secretion is the mantle. The source of the carbonate is probably from metabolic CO2 and the maintenance of ionized Ca concentration in the mantle is controlled by carbonic anhydrase. The Ca is stored in extracellular concentric spherical granules(0.6-5.5μm) which represent a large amount of inertCa in the mantle. The purpose of this investigation was to examine the role of raw river water and well water on shell formation in the fingernail clam.


Author(s):  
Michael Thompson ◽  
M. Bruce Beck ◽  
Dipak Gyawali

Food chains interact with the vast, complex, and tangled webs of material flows —nitrogen, phosphorus, carbon, water, energy—circling the globe. Cities and households are where those material flows interact with the greatest intensity. At every point within these webs and chains, technologies enable them to function: from bullock-drawn ploughs, to mobile phones, to container ships, to wastewater treatment plants. Drawing on the theory of plural rationality, we show how the production and consumption of food and water in households and societies can be understood as occurring according to four institutionally induced styles: four basic ways of understanding the world and acting within it; four ways of living with one another and with nature. That there are four is due to the theory of plural rationality at the core of this chapter.


Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2940
Author(s):  
Antonella Curulli

Safety and quality are key issues for the food industry. Consequently, there is growing demand to preserve the food chain and products against substances toxic, harmful to human health, such as contaminants, allergens, toxins, or pathogens. For this reason, it is mandatory to develop highly sensitive, reliable, rapid, and cost-effective sensing systems/devices, such as electrochemical sensors/biosensors. Generally, conventional techniques are limited by long analyses, expensive and complex procedures, and skilled personnel. Therefore, developing performant electrochemical biosensors can significantly support the screening of food chains and products. Here, we report some of the recent developments in this area and analyze the contributions produced by electrochemical biosensors in food screening and their challenges.


2021 ◽  
Vol 13 (11) ◽  
pp. 6185
Author(s):  
André Ruoppolo Biazoti ◽  
Angélica Campos Nakamura ◽  
Gustavo Nagib ◽  
Vitória Oliveira Pereira de Souza Leão ◽  
Giulia Giacchè ◽  
...  

During the initial months of the COVID-19 pandemic, farmers worldwide were greatly affected by disruptions in the food chain. In 2020, São Paulo city experienced most of the effects of the pandemic in Brazil, with 15,587 deaths through December 2020. Here, we describe the impacts of COVID-19 on urban agriculture (UA) in São Paulo from April to August 2020. We analyzed two governmental surveys of 2100 farmers from São Paulo state and 148 from São Paulo city and two qualitative surveys of volunteers from ten community gardens and seven urban farmers. Our data showed that 50% of the farmers were impacted by the pandemic with drops in sales, especially those that depended on intermediaries. Some farmers in the city adapted to novel sales channels, but 22% claimed that obtaining inputs became difficult. No municipal support was provided to UA in São Paulo, and pre-existing issues were exacerbated. Work on community gardens decreased, but no garden permanently closed. Post COVID-19, UA will have the challenge of maintaining local food chains established during the pandemic. Due to the increase in the price of inputs and the lack of technical assistance, governmental efforts should be implemented to support UA.


2012 ◽  
Vol 52 (No. 4) ◽  
pp. 187-196
Author(s):  
S. Aly ◽  
I. Vrana

The multiple, different and specific expertises are often needed in making YES-or-NO (YES/NO) decisions for treating a variety of business, economic, and agricultural decision problems. This is due to the nature of such problems in which decisions are influenced by multiple factors, and accordingly multiple corresponding expertises are required. Fuzzy expert systems (FESs) are widely used to model expertise due to its capability to model real world values which are not always exact, but frequently vague, or uncertain. In addition, they are able to incorporate qualitative factors. The problem of integrating multiple fuzzy expert systems involves several independent and autonomous fuzzy expert systems arranged synergistically to suit a varying problem context. Every expert system participates in judging the problem based on a predefined match between problem context and the required specific expertises. In this research, multiple FESs are integrated through combining their crisp numerical outputs, which reflect the degree of bias to the Yes/No subjective answers. The reasons for independency can be related to maintainability, decision responsibility, analyzability, knowledge cohesion and modularity, context flexibility, sensitivity of aggregate knowledge, decision consistency, etc. This article presents simple algorithms to integrate multiple parallel FES under specific requirements: preserving the extreme crisp output values, providing for null or non-participating expertises, and considering decision-related expert systems, which are true requirements of a currently held project. The presented results provides a theoretical framework, which can bring advantage to decision making is many disciplines, as e.g. new product launching decision, food quality tracking, monitoring of suspicious deviation of the business processes from the standard performance, tax and customs declaration issues, control and logistic of food chains/networks, etc. 


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