جستجوی مقالات مرتبط با کلیدواژه "restoration" در نشریات گروه "زیست شناسی"

Prolongation of wound healing time can be led to chronic infections. Therefor, to achieve infection preventive methods to accelerate of wound improvement process is one of essential needs of Human. In this study, the effects of methanolic extract of Holothuria leucospilota was investigated on restoration of created wound in rat skin.  Methanolic extracts of collected sea cucumber from depth of 10 to 15 meters was prepared by rotary. The amount of  0.5 and 1 gr of obtained extraction were added to base ointment. In continuing, 40 rats (average mean of 185±5 gr) were divided into 4 groups which included control, sham (base cream), 0.5% ointment and 1% ointment. Wound (diameter of 6±1 mm) was created on rats’ skin by punch biopsy.  Each group were treated (1ml) with prepared concentrations ointment during 13 days. On days of 0, 4, 7, 10 and 13, the wound improvement process was investigated and the diameter of the wounds was measured. According to results, accelerate the wound recovery process was more obvious in treated groups with 0.5% and 1% ointment compared to control and sham groups. Also, there was significant different between treated group with 1%, sham and control during days of 7, 10, 13 (P<0.05).

Today, wetlands around the world have been destroyed due to insufficient attention during the development plan. Population growth and changes in economic activities are indirect factors in the destruction of wetlands. Also, climate change, land use change, over-exploitation of wetland resources, pollution, eutrophication, infrastructure development and Invasive species are the direct causes of wetland destruction. The negative environmental, social, and economic impacts (Such as increasing the risk of floods, reducing the quality and quantity of water, adverse impacts on health, cultural identity and livelihood) have led many countries to pursue management plans. New methods of protection and restoration of these habitats are proposing today. Of course, wetland management is related to their economic and social value. Wetlands are managed for a variety of purposes, such as increasing fish production, storing water for irrigation and drinking, or for aesthetic reasons to promote tourism. In Iran, a comprehensive plan for ecological management and dealing with damage to wetlands has been adopted. Ecological management, improvement and restoration projects have been carried out for some southern wetlands of the Caspian Sea, such as Amir Kalayeh International Lagoon, Selkeh, Sorkhanhol Wildlife Refuge and Steel wetlands. Jokandan is another wetland considered in this regard. Jokandan wetland is located as a part of the Lisar and Jokandan protected area in Guilan. This wetland has ecological, economic, and tourist potential. But, lack of proper management has caused its destruction and drying up. Thus, the restoration of it with the aim of developing tourism is considered by the authorities. If wetland restoration and tourism development projects are not accompanied by proper planning and assessment of the current situation, it will cause damage to the environment. So, before taking any action, it is necessary to examine the status of the study area from environmental, economic and social dimensions to determine the most appropriate management decisions and the relationship between human activities and habitat destruction. In this regard, various models and patterns have been created. To study the environmental status, a model called (DPSIR) Driving force, Pressure, State, Impact, Response was developed by the European Environment Agency. In the first step, by evaluating the sensitivity of the study area based on this model, potential environmental problems can be identified and solved. Following the status of the wetland, it is necessary to quantitatively evaluate the solutions and responses provided by the authorities on the environment. One of the most effective tools in this regard is environmental impact assessment. So, the present study was conducted with the aim of increasing the efficiency of management measures to rehabilitate Jokandan wetland to develop tourism. For this purpose, DPSIR model and EIA method are integrated.

The present study is descriptive-analytical and has been done in two stages of basic studies and environmental impact assessment studies. First, in the basic studies section, using the DPSIR model, the condition of the wetland is described, environmental problems and its management challenges from environmental, economic and social dimensions are discussed. According to this model, the driving forces and pressures are often human factors for development and are associated with the consumption of natural resources. This causes a change in the environmental condition (environmental, physical, biological and chemical conditions) of the ecosystem. In this study, based on library studies and field visits, a list of management problems and environmental issues of Jokandan wetland was prepared with the opinions of experts. These factors were then categorized within the framework of DPSIR, which are known as pressure factors in large areas of the lagoon. These pressures have changed the condition of Jokandan wetland and have led to adverse impacts on this habitat. Then, in the impact assessment phase, the restoration activities of Jokandan wetland in order to develop tourism were quantitatively analyzed using a rapid impact assessment matrix. Restoration activities include the construction phase (dredging and sediment extraction, wetland expansion, cutoff construction, construction of ecotourism structures and bird watching sites) and operation (use of tourism and ecotourism capacity). To quantitatively evaluate the impacts, scoring matrices were first constructed separately for construction and operation phases. In these matrices, the impacts of activities on environmental components are placed in rows and scoring criteria in columns. Based on individual judgments and within the framework of the rapid impact assessment matrix method, the assessment team assigned an accurate value to each of the matrix cells.

According to the identified DPSIR model indices, the driving forces that cause pressures on the resources of Jokandan wetland are divided into four categories. These factors include unsustainable use of natural resources, land use change, low level of local community participation in wetland management, population growth and settlements. The most significant changes that observed due to the pressures in this area, are the increase in agricultural-range land use, increasing demand for water, and reduces the area of wetland habitat. Also, based on the results of the quantitative impact analysis, negative and important impacts of construction phase activities that appear in the range of many significant changes include noise pollution, the impact of clearing, shrubs and Cutoff construction on habitat destruction and land use in the region. The purpose of creating the Cutoff structure is to prevent the mixing of fresh water in the lagoon and salt water in the sea. Based on the present evaluation study, the creation of this structure will be subject to specialized studies. Also, according to the results, salinity does not interfere with the growth and development of alder trees, but monitoring salinity is essential. In the operation phase, the most important negative impacts include transportation activities on air quality and ecosystem simplification activities. According to final environmental evaluations the score of the construction phase is -764 and the score of the operation phase is 338. Summarizing the results and the difference in the range of scores shows that the negative impacts from the construction phase of the operation are decreasing and the positive impacts from the construction phase of the operation are increasing. This study highlights the importance of developing a comprehensive restoration plan.

The aim of this study was determining the physiological and morphological responses of two-year-old common ash (Fraxinus excelsior L.) seedlings to flooding stress. For this purpose¡ seedlings of common ash were examined in a completely randomized design for 102 days under continuous flooding¡ temporary flooding treatment (for 60 and 42 days drainage¡ respectively) and control. Stomatal conductance¡ transpiration¡ and photosynthesis rate were progressively decreased by flooding while all seedlings survived at the end of flooding. Also¡ flooded plants were able to adequately recover their physiological activities. In addition¡ height¡ root length¡ leaf area¡ and biomass accumulation of seedlings decreased under flooding conditions (particularly in continuous flooding). Diameter growth on the other hand¡ increased in seedlings subjected to temporary flooding. Overall¡ the results showed that two-year-old seedlings of F. excelsior had a suitable response to flooding stress until day 60. After 42 days drainage¡ the physiological characteristics of the seedlings were recovered. Generally¡ on the basis of the findings in this research¡ it is expected that F. excelsior can be used for the purpose of restoration of lowlands and wood production in areas subjected to periodic flooding.