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81.
Patrick M. Tchepmo Djomegni Emile F. Doungmo Goufo Subrata K. Sahu Mohamed Mbehou 《Natural Resource Modeling》2019,32(4)
A model is proposed to understand the dynamics in a food chain (one predator‐two prey). Unlike many approaches, we consider mutualism (for defense against predators) between the two groups of prey. We investigate the conditions for coexistence and exclusion. Unlike Elettreby's (2009) results, we show that prey can coexist in the absence of predators (as expected since there is no competition between prey). We also show the existence of Hopf bifurcation and limit cycle in the model, and numerically present bifurcation diagrams in terms of mutualism and harvesting. When the harvest is practiced for profit making, we provide the threshold effort value that determines the profitability of the harvest. We show that there is zero profit when the constant effort is applied. Below (resp. above) , there will always be gain (resp. loss). In the case of gain, we provide the optimal effort and optimal steady states that produce maximum profit and ensure coexistence. Recommendations for resource managers As a result of our investigation, we bring the following to the attention of management:
- 1. In the absence of predators, different groups of prey can coexist if they mutually help each other (no competition among them).
- 2. There is a maximal effort to invest in order to gain profit from the harvest. Above , the investment will result in a loss.
- 3. In the case of profit from harvest, policy makers should recommend the optimal effort to be applied and the optimal stock to harvest. This will guarantee maximum profit while ensuring sustainability of all species.
82.
Singh Swati Bawitlung Laldingngheti Singh Munmun Kumar Chauhan Amit Padalia Rajendra Chandra Pal Anirban Verma Ram Swaroop 《Chemistry of Natural Compounds》2022,58(1):161-162
Chemistry of Natural Compounds - 相似文献
83.
Gogoi Deepshikha Hussain Amreen A. Pal Arup R. 《Plasma Chemistry and Plasma Processing》2019,39(1):277-292
Plasma Chemistry and Plasma Processing - We report plasma based fabrication of an optoelectronic device with plasmon enhanced infrared sensitivity realized by integrating plasmonic gold... 相似文献
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Research on Chemical Intermediates - The discharge of hexavalent chromium [Cr(VI)] has resulted in significant pollution because of the presence of Cr(VI) oxyanions. They are highly water-soluble,... 相似文献
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This work aims at elucidating the mechanism of solvation of a radical ion pair (RIP) in a micro‐heterogeneous binary solvent mixture using magnetically affected reaction yield (MARY) spectroscopy. For the exciplex‐forming 9,10‐dimethylanthracene/N,N‐dimethylaniline system a comparative, composition‐dependent MARY line‐broadening study is undertaken in a heterogeneous (toluene/dimethylsulfoxide) and a quasi‐homogenous (propyl acetate/butyronitrile) solvent mixture. The half‐saturation field extrapolated to zero‐quencher concentration, B1/2, and the self‐exchange rate constants are analyzed in the light of solvent dynamical properties of the mixtures and a dielectric continuum solvation model. The dependence of B1/2 on the solvent composition is explained by cluster formation giving rise to shortened RIP lifetimes. The results are in qualitative agreement with the continuum solvation model suggesting that it could serve as a theoretical basis for quantitative modeling. 相似文献
88.
Martins Marina Roberto Johann Gracielle Palú Fernando da Silva Edson Antonio 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7411-7420
Journal of Thermal Analysis and Calorimetry - Due to the huge variety of therapeutic properties found in plant leaves, many of these are widely used in traditional medicine. Among these plants,... 相似文献
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