نشریه خشک بوم
سال سیزدهم شماره 2 (پاییز و زمستان 1402)

In this study, drought was investigated on water use efficiency (WUE) in different climates and uses of Tehran province. To calculate the efficiency of water consumption, the products of Gross primary production (GPP), Evapotranspiration (ET) and Palmer drought severity index (PDSI) obtained from the MODIS meter are used. Then the trend of changes in the index of primary gross production, evaporation and transpiration, water consumption efficiency and drought in the period of 2001-2021 using linearity and Mann-Kendall and slope tests, and then the response of water consumption efficiency to drought in different climates and consumptions with Use. It was evaluated from correlation analysis. By dividing annual rainfall into potential evapotranspiration (PET), the Aridity index (AI) was calculated and climate classification was done with the help of this index. The results showed that the indices of evapotranspiration, primary gross production and drought increased by 81.15, 86.86, and 99.99% respectively, and the water consumption efficiency index decreased by 76.24% in this 20-year period. Is. These results were confirmed by the slope test. Examining the relationship between the efficiency of water consumption and drought in different climates and applications showed that in dry climates, agricultural land and bushland had a negative ratio of 91.86 and 78.93, respectively, and pasture consumption had a positive ratio of 51.96. Agricultural lands, pastures and bushland related to semi-arid climate have increased by 85.38, 66.22, and 64.27 percent, respectively, and forest use has decreased by 84.87 percent. In semi-humid climate, respectively, 47.53, 60.48, 73.41% of the study area has a positive relationship in the use of agriculture, pasture and shrub land, and 91.30% of the use of forests has a negative relationship. In the climate, the negative impact of drought has been in 66.04, 61.15 and 50.56 percent of agricultural, pasture and forestry lands. In general, according to the mentioned results, drought has had a negative effect on water consumption in Tehran province, and it can be said that the resistance of the ecosystem against drought is determined by our correlation between drought index and water consumption efficiency.

Dust storms are natural phenomena but with serious and destructive effects on the environment and human societies. The southeast region of Iran is one of the most active sources of dust storms in Asia, dust storms occur in this region almost all year round, but their frequency is higher in summer and spring. This study aims to investigate the dust storm anomaly in the southeast of Iran during a period of 21 years (2000-2020) and its relationship with vegetation anomaly changes. The DSIA was used to examine the spatial and temporal changes of dust storms, and the NDVIA was used to examine the changes in vegetation anomalies in the region. The correlation between DSIA and NDVIA was determined by using Pearson's coefficient. The temporal trends of DSIA show that from 2000 to 2012, it had a positive and increasing trend in most of the years of the study, and the highest value of DSIA occurred in 2012, which is equal to 96%. Then, from 2012 to 2020, this trend has been decreasing, and the lowest value of DSIA equal to -67% was observed in 2020. Also, moving from east to west of the studied area, the value of the DSIA decreased. The temporal trends of the NDVIA show that from 2000 to 2012, the trend of changes is downward, but from 2012 to 2020, the trend of changes is upward. In terms of time, the highest value of the NDVIA index is related to 2014, and in general, since 2012, this index has had positive and increasing changes. Pearson correlation results showed that the DSIA index is significantly correlated with the NDVI index, this correlation is negative (p-value<0.05 r=0.52) due to the negative and significant correlation between the NDVIA index and the DSIA index. Since 2012, with the increase of the NDVIA index and the improvement of vegetation conditions, the DSIA index has decreased. The effect of this correlation was also observed spatially, as moving from east to west of the region, with the increase of the NDVIA index, the amount of DSIA decreases. These results can be useful for decision-makers to assess the risks of dust storm impacts and reduce its negative consequences in the southeast parts of Iran.

Dust storm is one of the destructive weather phenomena that strongly affects regions with arid and semiarid climates like Yazd province. This phenomenon leads to many losses, including environmental, socio-economic, human health, climate and microclimate problems. Accurate spatial and temporal monitoring of dust can help identify the trajectories and sources of this atmospheric hazard and play a vital role in management and reduction of possible damages of storm. In the present study, three examples of dust storms that occurred in 2022 in Yazd province were analyzed. When the visibility is less than 3.5 km and one of the codes 06 to 09 or 30 to 35 is reported, it is considered as an effective dust storm. The lagrangian HYSPLIT model was used to identify the trajectories of dust transfer to Yazd province. The results of this model indicate that dust masses travel three main pathways to reach Yazd province: southwest, west-northwest, and northeast. In order to investigate the spatial distribution of dust and also to identify dust sources more accurately, the aerosol optical depth data based on remote sensing, the MOD04/MYD04_L2 product and also the MOD08_D3 product, were used. These images showed that the external sources of dust are the large deserts of Iraq, Syria, the Arabian Peninsula, and the desert of Turkmenistan, and the internal source of dust is the desert areas located in the provinces of Semnan, Isfahan in the northeast of Yazd province. In addition, the Gavkhoni wetland in the northwest of the study area acts as an intensifier of the dust transferred from the western borders of the country. Also, the results obtained from the satellite data and the HYSPLIT model are consistent with each other.

The main purpose of this research is to investigate the role of social capital in the environmental protection of agricultural lands in dry areas. The statistical population of this research included all the farmers of Bavi County (Khuzestan province). A sample size of 390 people was selected for the study using a stratified sampling method with proportional assignment. The data collection tool is a questionnaire, the validity of which was determined based on the opinion of the faculty members of Agricultural Sciences and Natural Resources University of Khuzestan, and its reliability was determined through Cronbach's alpha. On the other hand, the Average Variance Extracted Index (AVE) was used to determine construct validity and the Composite Reliability Index (CR) was used to determine model reliability. The results of prioritizing the environmental protection of agricultural lands in dry areas showed that the two behaviors "use of plow at least to reduce soil erosion" and "use of organic and animal fertilizers in the field" were respectively of higher priority among farmers. In addition, the results of structural equation modeling showed that the dimensions of social capital (social norms, social awareness, social networks, social participation and social trust) have a significant effect on the environmental protection behavior of agricultural lands in arid regions, which were finally able to reach 73% To explain the variance of the dependent variables of the research, i.e. environmental protection of agricultural lands in dry areas. The findings of this research, while adding new knowledge to the literature on environmental issues in dry areas, can be useful in planning and policy-making to reduce environmental problems caused by the agricultural sector.

Mangrove ecosystems have abundant ecosystem services and play a significant role in the coastal ecosystems sustainability. Thus, the aim of this research is to investigate the temporal and spatial trends of mangroves habitat changes in the Nayband marine national park and the Bahu-kalat protected area, as well as determining the intensity of fishing activities as human threats to these mangroves. To examine the temporal and spatial trends of these mangroves, four plant indices, namely NDVI, SAVI, LAI, and RVI, were estimated and to determine the intensity of fishing activities, a map of mangrove habitat extent was drawn, consisting of 189 and 391 grid cells with dimensions of 4x4 kilometers, covering the coastal waters of the Nayband and Govater mangroves. Additionally, data on the geographical location and the number of vessels in the fishing ports of Bushehr and Sistan and Baluchestan provinces were collected. The findings of this investigation demonstrate an expansion in the area of all the studied mangroves from 1990 to 2019. On average, an increase in the Bidekhoon habitat from 32.96 hectares to 123.93 hectares was observed in Nayband Gulf, while in Gwadar Gulf, the area expanded from 275.76 hectares to 396.72 hectares. The reduction of mangroves in this region between 2000 and 2010 can be attributed to various factors, including local community harvesting of mangrove shoots, pollution from oil and gas industries, tourism, and the influx of non-degradable waste due to the proximity of these habitats to residential areas. Similarly, in Gwadar Gulf, the primary factor contributing to changes in hydrology and the subsequent decline of these forests since 2015 has been aquaculture. The most significant factors influencing the growth and establishment of the studied mangrove habitats are increasing temperatures and rising sea levels. Furthermore, the results showed that based on the current status of the studied mangrove habitats, the geographical distribution of fishing ports and the number of fishing vessels present in them, the Govater mangroves are subjected to higher fishing activity intensity compared to the Nayband mangroves.

The Asian houbara (Chlamydotis macqueenii) is an important bird species in the steppe areas of Iran, including the south of Kerman. Populations of this species have significantly decreased due to various reasons, and the species is considered a threatened species. This approach was used to analyze the strengths, weaknesses, threats, and opportunities of the steppe areas in the south of Kerman province, which is the habitat and migration corridor of the Asian houbara, using quantitative and qualitative approaches and providing suitable management strategies in these areas. In this research, questionnaires were designed and completed by 15 experts in the region. Results showed that the most important strength is the geographic location of the region and its role as a corridor for species migration, and the most important weakness is the continuous drought, the lack of sufficient water resources in the south of Kerman, and the destruction of the vegetation in the region. Illegal hunting, poaching, live capture and smuggling of the Asian houbara were identified as the most important threatening factors due to the economic and cultural poverty of the people. The quantitative strategic planning matrix showed that the officials` attention to the region as one of the most important houbara habitats in the country and introducing the values of the rare and valuable species to the local community can motivate them to conserve their habitats. More scientific research projects about the capabilities of this region are also required. In addition, increasing the region`s security to prevent traffickers is important for strategic planning.

Salehiyeh Wetland, located in Alborz and Qazvin provinces, is one of the wetlands that has dried up in recent years and has become a center for dust production. The aim of this study is to evaluate the trend of changes in moisture in Salehiyeh Wetland and investigate the role of drainage channels in the drying of the wetland bed. To achieve this goal, the MNDWI index was calculated using Landsat 5, 7, 8, and 9 satellite images from 1990 to 2023. The construction of drainage channels has caused some changes in the wetland catchment area. Therefore, the non-parametric Mann-Kendall test was performed before and after the construction of drainage channels in two previous and current catchment areas. Also, the wind data from synoptic stations around the wetland were analyzed by drawing the storm rose diagram. The results of the study show that the overall trend of changes in moisture in Salehiyeh Wetland during the study period has been decreasing, and the MNDWI index has been negative in most years due to the drought prevailing in the region. Due to this, the phenomenon of dust and the problems resulting from it have spread to the surrounding cities. Therefore, measures need to be taken to preserve and manage the water resources of Salehiyeh Wetland and prevent its drying, such as optimizing water consumption, preventing the construction of inappropriate drainage channels, and using various solutions such as implementation of mechanical windbreak to reduce the sand and dust storm.

Watershed is the base of human societies interact with their surroundings, which have been affected by various problems. Accordingly, the evaluation of the stability of the watershed areas is inevitable. Considering the existing resources for evaluating and selecting a suitable method and quantifying the stability of the water, it seems a solution to select the appropriate method in evaluating the sustainability of the water. In this regard, to evaluate the sustainability of the Forg Watershed District in South Khorasan Province, based on the Help approach, aimed at determining the stability of this watershed area during 2006 to 2023. 12 variables were determined to investigate the stability of the basin and were based on the nature of the pressure, state and response indicators. The average privileges of hydrology, environmental, life and policy criteria were 0.238, 0.45, 0.50 and 0.57, respectively. The results showed that the stability of the area was classified by 0.40 on the low stability floor. The low stability of the watershed has caused any changes in the status of the watershed area to reduce stability and cause adverse conditions that will cause further destruction of the watershed. Therefore, it is suggested that the management and administrative policies of the Forg Watershed are in order to maintain the current conditions and promote the health of the watershed sub -areas, relying on the control of human activities and its related factors.

The cement industry has always been known to have significant harmful environmental effects. The development of green infrastructure around these industries can reduce the negative environmental effects of such developments in the surroundings. However, there is no systematic framework related to the selection of plant species around cement factories. The aim of this study is to provide a systematic method for selecting plant species around cement factories. In this study, Durood Cement Factory was selected as a case study. At first, the conceptual model of plant-environment relationship in industrial environments was introduced. In the following, a functional framework for the implementation of this conceptual model is presented, which consists of five steps: identifying effective criteria, weighting criteria, developing a formula for selecting plant species, creating a plant palette, and screening suitable plant species. In the selection of criteria, two categories of primary and secondary criteria were used. The screening method of plant species selection criteria is fuzzy Delphi and the method of weighting the selection criteria is Analytical Hierarchy Process (AHP). The results of this research showed that among the five investigated plant species, Eleagnus angustifolia is the most suitable tree species for this study area, while the Platanus orientalis and Tamarix gallica are considered unsuitable. This research provides valuable insights for landscape architects, environmental managers and operators of industrial spaces, especially cement factories, to create sustainable green areas.