Environmental Economics
Ardavan Zarandian; Fatemeh Mohammadyari; Roya Mousazadeh; Majid Ramezani Mehrian; Jalil Badamfirooz
Abstract
Introduction: Soil resources play an important role in providing the necessary material goods for humans and other organisms and also deliver multiple ecosystem services that are essential for life on earth. They have also served for a long time as an important green infrastructure in protecting agricultural ...
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Introduction: Soil resources play an important role in providing the necessary material goods for humans and other organisms and also deliver multiple ecosystem services that are essential for life on earth. They have also served for a long time as an important green infrastructure in protecting agricultural and forest landscapes by providing plants a foothold for their roots and holding the necessary nutrients for their growth. In addition, soils can provide various ecosystem services such as contaminant immobilization, rainwater control, carbon sequestration, and habitat provision that are directly beneficial for humans. Services provided by ecosystems for humans are called ecosystem services. Soil retention, which refers to the potential of ecosystems for controlling soil erosion and conserving soil, is classified in the class of regulating services. Materials and Methods: The InVEST Sediment Delivery Ratio (SDR) model was used in InVEST Software to quantify soil retention and erosion. The required inputs for implementing this model include land use maps, K-factor (soil erodibility), R-factor (rain erosivity), C-factor (land use and land cover or LU/LC), P-factor (support practices), DEM (digital elevation model), and the biophysical table. Results: Based on the results, the potential of soil loss and sediment transport in the study area ranged from zero to 248.18 t/pixel and from zero to 57.25 tons per pixel, respectively. Soil retention is also estimated in a range from zero to 124.85 tons per pixel in the studied area. The largest amount of soil loss happened in sub-basin number 14 with 13716400 t/year and the smallest in sub-basin number 4 with 416594 t/year. Most of the ecosystem service of soil retention belonged to sub-basin number 13 with 4304414 t/ha/ year and the least to sub-basin number 4 with 5645 tons/ha/year. Discussion: The dense forests in the northernmost part of Semnan Province provide the most part of the ecosystem service of soil retention with more than 36 t/ha and the desert areas, the salt lake, and the salt marsh the least. Based on this, the province's forests, including dense, semi-dense, sparse and thin forests, contribute to the maintenance of soil in the province by a total of 4269166 tons per year. Also, good pastures maintain more than 18 tons per hectare of the province's soil every year, and the total function of soil maintenance by all types of pastures in the province, including good, medium and poor pastures, is 9395160 tons per year. Since the area covered by the pastures is 18 times more than that by the forests, we can say that most of the ecosystem service of soil retention is provided by the pastures due to the geographical distribution of this service in the province, despite the fact that forests are more capable in soil conservation than pastures. The orchards and rainfed agricultural land rank third and fourth, respectively, in soil retention with 7.86 and 2.15 tons of soil/ha, respectively. However, man-made land uses such as urban areas decrease this ecosystem service because they are usually accompanied by removing or reducing the vegetation. The urban areas are located in the northern part of the study area, and they have negative impacts on this ecosystem service. Therefore, protection of the forest and rangeland covers in the province is vitally important for the continued conservation of the ecosystem service of soil retention.
Seyed Ghasem Ghorbanzadeh Zaferani; Seyed Keramat Hashemi ana; amin ahmadi gaevi; Mehdi blouki; mohammad amin tolab; Ardavan Zarandian; Farhad Tayefeh
Abstract
Introduction: Considering the importance of corals in different dimensions of human life, their investigation and study will become more necessary. Kharg and Khargo islands are very important from the point of view of the environment, especially the unique coral covers. In the past few decades, many ...
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Introduction: Considering the importance of corals in different dimensions of human life, their investigation and study will become more necessary. Kharg and Khargo islands are very important from the point of view of the environment, especially the unique coral covers. In the past few decades, many potential threats such as destructive human activities related to the oil industry and the resulting wastes in coastal environments, oil and hydrocarbon pollution, industrial and urban pollution, air pollution, discharge of municipal effluents and sewage, thermal stresses caused by changes Climatic and fluctuating middle and upper water levels, fishing with nets by fishermen and hunting fish by divers in coral areas, as well as carelessness of divers, have faced many challenges in coral habitats. One of the activities that is in relative conflict with the ecosystem of Khark Island and especially the location of the coral beaches, is the activities and movements related to fishing in Khark and Khargo Island. These activities date back several decades. Extreme poverty in many areas has caused a large number of people to go fishing. Therefore, the purpose of this study is to examine the various aspects of the fishing challenge that threatens the geographical territory of coral reefs. The aim of this study is to emphasize the investigation of human-environmental challenges.
Materials and Methods: In this research, for evaluate and investigate the threats created in the geographical area the first step we investigated the challenges of fishing activity of Khark Island. Then these challenges were classified and finally analyzed and investigated the contribution of each of its aspects in the fishing communities near the coral habitat of Kharg and Khargo islands. In order to investigate fishing and fishing challenges, using the statistical method of Cronbach’s alpha analysis and Likert scale. For trust final results and analyzes must the confidence percentage was calculated and confirmed. The weights of each of the criteria were finalized by the SWARA fuzzy-numerical test. In this questionnaire, there are 21 questions and Cronbach’s alpha is at an acceptable and good level of 0.72.
Results: In the questionnaire of this research, there are 21 questions and the Cronbach's alpha level is at an acceptable and good level of 0.72. It was found that trust in the content of the questionnaire confirms. The effectiveness and weight of each of the criteria showed that the highest percentage of fishing is done by motor boats in the winter season and early in the morning (93%). The results showed that more than 85% of fishermen have not received any necessary training for fishing in coral areas, and this challenge is considered serious and fundamental. The results showed that more than 85% of fishermen have not received any necessary training for fishing in coral areas, and this challenge is considered serious and fundamental.
Discussion: The output indicates that the fishing tool is valued as a criterion with the first rank, in other words, it explains 31% of the weight of the items. On the other hand, fishing time has the lowest weight in the criteria definition with 23%. These statistical processes show that human-environmental factors should be prioritized in examining the challenges and threats of the coral reef in Khark Island. In other words, the control and management of man-made challenges and related factors can create safe coral environments.