نشریه مرتع و آبخیزداری
سال هفتاد و ششم شماره 4 (زمستان 1402)

In the recent years, science and technology in urban green space have largely focused on technologies that facilitate infiltration and reduce runoff (such as rain gardens and permeable sidewalks). Trees in urban green space reduce the net rainfall by interception, and on the other hand, their extensive root systems allow them to store and direct significant amounts of water into the soil. The present study investigates the effect of rainfall amount and tree species on rainfall interception in Hashtgerd city of Alborz province during two seasons of winter 2017 and spring 2018. For this purpose, during seven rainfall events, the amount of throughfall was measured by the number of five rain gauges installed under each tree. In order to record rainfall events, a rain gage container was installed in a location that was sufficiently distant from buildings and trees, and rainfall events ranging from 2.1 to 6.8 mm were recorded. The results showed that the percentages of rainfall interception for spruce, apricot, fig, willow, walnut, and oak species were 44.6, 42.6, 36.4, 35.1, 33.6 and 30.4 percent, respectively. The results of statistical analysis showed that there is a significant difference among the values of rainfall interception in different tree species (P <0.01). Also, there is a significant difference among the rainfall interception in the rainfall classes (low (lower than 4 mm), medium (4-6 mm), and high (higher than 6 mm)) (P <0.01). Among the studied species, sparrow and apricot species have the highest rainfall interception, which it is possible to make more use of these two types in the control of runoff with urban planning.

Due to the lack of water in the deserts of Iran and the high rate of evaporation, the establishment of vegetation and their irrigation are associated with many problems. Therefore, in the management programs for the sustainable development of dry and desert areas, it is very necessary to use less water. Among these methods, deep subsurface irrigation using PVC pipes can be mentioned. In this study, a hole with a depth and diameter of 50 cm was dug, and then two pipes were mutually placed at a distance of 20 cm from each other on both sides of the pit. After placing the pipes, the pit was filled with soil. The wetting pattern in eight treatments has been examined in terms of the location of the water exit holes, the diameter of the pipe, the number of holes in the upper and lower half of the pipe, as well as the diameter of the holes. The results demonstrated that pipes with a diameter of 12.5 cm and a height of 55 cm, with five double rows of 6 mm holes in the upper half of the pipe at a distance of 3 cm from each other and two holes in the lower half of the tube at a distance of 10 cm from each other, The best depth of wetting pattern is created. The depth of the wetting pattern created in the soil around the plant root as a representative of water use efficiency is very important in the management and correct use of water resources as well as encouraging the plant to take deep roots. .

This research was carried out in an enclosure rangeland with four habitats of Artemisia sieberi, Zygophyllum eurypterum, Stipa barba and Amygdalus scoparia in the Shaskouh protected area, South Khorasan province. All the plant species of the rangeland were identified and counted in 200 plots, due to the different vegetation form and distribution of each of the dominant species, in each of the four habitats, 20, 40, 60 and 80 plots (respectively) were established with two plot size: 2 × 2 meters and 4 × 4 meters (60 plots each). Numerical indices and diversity ordering curves were used to compare four habitats. Alpha and gamma species richness were determined by numerical indices and single sample rarefaction and pooled rarefaction curves were used to compare species richness and determine data adequacy. The results showed that the total species richness (gamma) varies between 51 and 54 species. The habitat with 80 plots has the highest richness and diversity (S=43 and H=3.27) and 20 plots has the lowest richness and diversity (S=6 and H=1.41). The results of SHE analysis showed that with the increase in the number of plots, species evenness decreased. The pooled refraction curve showed that by increasing the number of plot to 110, all plant species will be observed. With the increase in plot size all values of species richness and diversity indices increased significantly (p≤0.01). Species evenness indices were not affected by plot size. The results of the present research showed that the numerical indices of species richness and diversity are dependent on plot size, and this is one of the disadvantages of evaluating biodiversity in rangeland using numerical indices.

Coping with climate change (CC) is part of the way to face this phenomenon. This depends on the understanding of CC and the degree of adaptability to it.

The research was conducted with the aim of measuring the level of nomads' understanding (NU) of CCe and their adaptation strategies (AS) in the face of CC.

The research was descriptive and the data collection tool was a questionnaire whose items were obtained based on interviews.

NU of the effects of CC is not the same. According to them, CC has had the most obvious impact on vegetation. The priority of AS is also different in the face of CC. A positive relationship was observed between understanding the effects of CC and the degree of adaptability in facing CC. Nomads who had a better understanding of the effects of CC have used livestock management strategies to adapt to it. Age and history of animal husbandry had a positive relationship with the level of understanding of the effects of CC. A negative and significant relationship was also observed between the number of animals and the degree of compatibility.

The NU of CC and its effects on the ecology of the environment is an important starting point in dealing with the negative effects of CC and choosing appropriate strategies to adapt or deal with it. So that the selection of suitable adaptation methods by the nomads reduces the vulnerability of CC on the condition of livestock and rangeland.

Coal mining in rangelands accounts for a considerable amount of waste dumps that can be colonized by local plants over time. A thorough understanding of vegetation changes plays a key role in the management and restoration of such ecosystems.

This study aimed to assess the rangeland plant changes during 10 years on coal-waste dumps.

This study was carried out on three coal-waste dumps which were abandoned between 20 and 30 years in Karmozd mines in Savadkoh County, Mazandaran Province. Vegetation sampling was done in 2012 and 2022, estimating the cover percentage of all species in each 1 m2 plot. Species composition, functional groups, and species richness and diversity were compared between the two years.

Results showed changes in species composition and plant groups after 10 years. Some species were not found in 2022 while some new species were detected. The cover percentage of Bromus briziformis and Melica persica significantly increased but Hordeum vulgare was found to significantly decrease. The cover percentage of annuals and perennials significantly increased by 35.28% and 46.19%, respectively. Over the time, the cover percentage of grasses, forbs, and shrubs significantly increased. The results of ANOVA indicated a significant increase in species richness and diversity.

Vegetation changes during this period have not been affected by age of each dump since abandonment. Restoration treatments and plant species with phytoremediation potential are recommended to accelerate vegetation dynamics and reduce the consequences of coal-waste dump on the surrounding environment.

Rangelands are one of the essential components of natural ecosystems and are known as one of the main sources of forage supply, biodiversity conservation, soil and water resources. The aim of this study was to investigate the ecological potential of rangelands in Alborz province based on the Analytic Hierarchy Process (AHP) and pairwise comparisons using Geographic Information System (GIS). The digital map of ecological potential (EP) was prepared by weighting and integrating maps of slope, land unit, vegetation cover, land use, and precipitation. The results showed that each of the five criteria had equal importance coefficients (0.2) for determining the EP of rangelands. Overall, 21.77% of the province's area was unsuitable for rangeland use due to rocky outcrops. 15.41% of the province's area had first-degree potential and 37.28% had second-degree potential for rangeland use. Taleqan County had the highest first-degree potential for rangeland use with 56,321 hectares, and Karaj County had the highest second-degree potential with 96,507 hectares. Nazarabad County had no first-degree potential for rangeland use, and Taleqan County had no fourth-degree potential. Nazarabad County and Eshtehard County also had 48.15% and 63.92% potential for third- and fourth-degree rangeland use, respectively. Based on the weighting of different factors, slope was the most limiting factor for rangeland use, accounting for more than 50% of the limitation. In general, determining the EP of rangelands leads to identifying areas that are very suitable for optimal use of natural resources, and can increase rural income and employment both economically and socially.

Climate has an important role in agricultural activities and can be examined from two perspectives. First, what locations are suitable for a specific plant, and second, what plants are suitable for a climate. The latter approach is less considered; thus in this study, it has been investigated by introducing a standard method (Sys method). The study area is located in Mako city. Climatic suitability evaluation was performed by numerical (parametric) method using the Maku Synoptic Station data for pistachio, almond, pears, plum, sour cherry and sweet cherry. The findings showed that except for pistachio, with marginally suitable class (S3), other plants were classified as moderately suitable class (S2) but the value of climatic index for each crop was different. The introduced method made it possible to identify the most important effective climatic factors for the cultivation of each plant and determine the most limiting factor in the phenological period. Such findings showed that there is a close relationship between crops, phenological period, climatic characteristic and location. Based on this, the most suitable plant or plant species can be selected for a region, using the phenological period of the plant and climatic characteristics. However, for sustainable development, other components of the land, such as soil and/or topography, should also be evaluated. In general, the introduced approach can be used as an efficient tool, both for choosing the most suitable plants in a climate and for choosing the most suitable place (in terms of climate) for specific plants.