Vol. 11, No. 1 (2023): Regular Issue

The present study deals with the dynamical response of a predator-prey model in which the prey has been subjected to harvesting. The proposed model considers a Crowley-Martin response function which is subjected to Michaelis-Menten type prey harvesting. It is first shown that the system is bounded and the conditions of existence and stability of the equilibria of the proposed model have been furnished. Next the presence of Hopf bifurcation and limit cycles have been shown to explain the transition of the model from a stable to an unstable one. It is seen that harvesting effort has a remarkable effect on the dynamics of the system and can make the system undergo unstability by reaching beyond a critical value. Considering the discrete time delay as bifurcating parameters, the conditions for existence of limit cycle under which the system admits a Hopf-bifurcation are investigated. The detailed study for direction of Hopf-bifurcation have been derived with the use of both the normal form and the central manifold theory.

Industrial discharges of phosphate constitute an enormous danger for the environment, because of their high content of heavy metals, which causes contamination of water and soil. The current study aims to measure the trace metal pollution (Al, Cr, As, Se, U, Fe, Si, Sr, Li, Zn, Pb, Ni, and Cu) in surface waters, spring waters and groundwater found in the Djebel Onk. Phosphate treatment Area in order to assess the magnitude of the risk on the health of the people. Thus, samples were analyzed using the Inductively Coupled Plasma Mass Spectrometry method. The results show that the surface water, spring waters, and groundwater are contaminated by these trace metals, particularly lead, uranium, iron, lithium, selenium, and magnesium. It has been observed that the average maximum levels in groundwater are iron 24.32 mg/l, uranium 0.0017 mg/l, selenium 0.0365 gm/l, lithium 0.05 mg/l, lead 0.037 mg/l, while in surface waters, the maximum iron content of 1.1565 mg/l, uranium of 0.021 mg/l, selenium of 0.021 gm/l, lithium of 0.327 and lead of 0.05 mg/l were observed, in spring waters the maximum iron, selenium and lead levels are 0.225 mg/l, 0.017mg/l, 0.031gm/l respectively, which are higher than the World Health Organization standard for drinking water. The consumption of these waters without treatment could have negative impacts on human health in general and that of children in particular.

Emerging environmental concerns call the companies to adopt environmental management accounting to align with their environmental, financial, and social goals. This study is performed in India's manufacturing sector to see how EMA adoption impacts its environmental, financial, and social performance. The study has also incorporated the impact of corporate environment ethics. This study is a quantitative study based on questionnaires, and the data were collected from 384 participants. The data analysis applying CFA and SEM has shown that EMA adoption of firms' financials, environmental, and social performance is significant and positive. Simultaneously, the mediation of corporate environment ethics is also significant and positive. The study is an authentic source for promoting EMA adoption by firms in India and worldwide to align its environmental, financial, and social goals.

The current investigation analyzed the connection between corporate water disclosures and financial performance in the Indian setting. For this purpose, the water disclosures scores were fetched from the Carbon Disclosure Project reports of all partaking Indian firms for the sample period 2018 to 2019. Further, return on assets, return on capital employed and return on net worth were used as a proxy of sample firms' financial performance. The study revealed that Indian firms have taken initiatives for being corporate water responsible and have openly revealed their endeavours through the Carbon disclosure project. However, this examination did not find any evidence to validate that the water divulgences influence firms' performance. These results are crucial for the managers and investors to know the financial consequences of willful water divulgence by the companies working in developing economies.

The study aimed to investigate the level and pattern of environmental, social and governance (ESG) disclosure in annual report of listed companies in the Stock Exchange of Thailand (SET), and to examine the relationship between ESG disclosure and Thai corporate financial performance. The population was all listed companies in the SET. Using annual reports during 2015 to 2019, content analysis by word counting was used to quantify the level and pattern of ESG disclosure in corporate annual reports, while financial performance was measured by corporate net income. Descriptive analysis, independent sample t-test, correlation matrix, and panel data analysis were used to analyze the data of this study. The results found that there was an increase of ESG disclosure in annual reporting during 2015 to 2019 by listed companies in the SET. The most common ESG disclosure was governance information disclosure following by social and environmental information disclosures. Moreover, there was the significantly positive relationship between ESG disclosure and corporate financial performance. Using control variables, stock reaction, firm age, firm risk, and ESG group had a positive correlation with corporate financial performance. The Findings can demonstrate that stakeholder theory can be used to explain the benefit of ESG disclosure, although the disclosure is still voluntary reporting in Thailand.

In order to achieve food security, various factors such as food safety as well as healthy and nutritious diet are the main core values of human health development in all societies across the world. One important strategy to achieve this goal is urban agriculture (UA). Therefore, the main purpose of this study was to investigate the role of UA in improving food security and safety. This research had an applied and quantitative nature in which the questionnaire was used as the research instrument. The statistical population included all residents ($n=574$) of the Tehran city in Iran, who had attended the courses focused on agricultural and extension education, held in plant clinics by observers and experts in all agriculture and natural resources' areas of each districtduring a three-month period (October, November, and December) of 2019. To determine the sample size, the Cochran formula was applied and a total number of 161 samples were selected using the simple random sampling method. In general, the study results demonstrated the positive and significant effect of UA functions on the food security. In this regard, environmental (0.807), economic (0.730), and social (0.192) functions were respectively distinguished as the most important factors shaping the food security. Moreover, the results revealed that the impact of environmental, economic and social functions of the UA on the food security were statistically significant at the level of 99%; while, the UA physical-mental function' effect on the food security was statistically meaningful at the level of 95%. Based on mentioned findings, in order for agricultural development and extension services to succeed in urban area, special place should be dedicated to UA and sufficient funding and facilities must be allocated by the government for the citizens who are willing to work in agriculture related fields and this should be seriously considered by the policy makers and authorities in the ministry of Agricultural-Jihad.

Ecosystem service assessment and accounting can offer a valuable approach for linking human activity and nature along with arguments for the conservation and restoration of natural ecosystems. This paper presents an analysis of four provisioning ecosystem services flows at national level: wood biomass provision, crop provision, fish biomass provision and water provision. The methodology applied for the assessment and accounts of each ecosystem service depends on the nature of the service and on data availability. Wood provision is based on fast track approach using data derived from economic aggregates. Crop and fish biomass provision accounts are based on official statistics on yield production. Here, we combine yield statistics with a novel approach to disentangle the yield generated by the ecosystem from what is generated by the human inputs (i.e., planting, chemical products, aquaculture). Water provision is based on a spatial hydrological balance model. Supply and use accounting tables have been developed for the four ecosystem services in line with the United Nations System of Environmental Economic Accounting (UN-SEEA) guidelines and Experimental Ecosystem Accounting (EEA) initiative. The results of this study provide an estimation of the functioning of the ecosystem over time (2012-2018): they help showing the direction of change in ecological and economic terms and the order of magnitude of this change rather than the exact value of Nature (namely ecosystem services). Notwithstanding this study has the merit of being the first exercise of its kind at national level on these specific ecosystem services, it points out the need for further research and in-depth analysis, both to improve the quality of the outcomes and for a better understanding of the estimates meaning.