نشریه مرتع و آبخیزداری
سال هفتاد و سوم شماره 3 (پاییز 1399)

One of the most important and main components of ecosystems is net primary production, which is an important index for assessing the ecosystems performance in the face of environmental changes. To this end, with regards to the importance of the subject, in this study, to quantify the climate change impacts on ecosystems, NPP values in Jiroft plain was simulated in two periods (2001- 2015and 2016-2030) using the BIOME-BGC model. To assess change in climatic parameters in future, LARS-WG 6 downscaling model was used. After ensuring the capability of the LARS-WG model to create climatic data, climatic variables were simulated in 2016-2030 under the RCP 4.5 scenario. NPP values in 2001-2015 were simulated using the BIOME-BGC model and validated with NPP data derived from Modis images (MOD17A3) that the results showed high accuracy of the model to simulate NPP. After ensuring the model accuracy, NPP was simulated under precipitation and temperature data in future (2016-2030). The results indicate an increase in precipitation, minimum and maximum temperature in the future period (2016-2030) compared with the baseline period (2001-2015). Also, according to the results, NPP value in future has increased in all biomes that this increase is due to increase in precipitation. There is the highest NPP value in the northern and western parts of the region that is related to biome 4 (with agricultural vegetation), biome 5 and 2 (with rangeland vegetation), respectively, and the lowest NPP value is related to the southern parts of the study area.

Due to physical and chemical composition and lack of vegetation cover and therefore less organic matter, Marlons formations are the most sensitive formations to erosion, so that by removing the particles of the soil and transporting their to the lower regions, cause different forms of erosions. Due to the physical and chemical properties of marls, the study area has caused various types of erosion in the basin and downstream urban areas has been affected followed by mudflows resulting from their erosion and sedimentation. In this research, 35 soil samples were taken from the different work units to determine the physical and chemical characteristics and also to study the soil losses using a rain simulator. Along to this, 5 samples from particular marl units of the area was taken and transferred to the laboratory for mineralogical experiments. The K method in the global erosion equation was used to evaluate the degradability of detached materials that according to this method, the highest value of k is related to forms with a coefficient of 70%, and the least of which is the surface and rainfall erosion form with a coefficient of 25%. Also, due to the fact that there were 4 units of work with attached materials, the stripy method was used to evaluate their erodibility.

Doing the research for monitoring, evaluating and comparing the results with the parameters of projects is essential in the most natural resources and watershed management projects. Also in flood spreading projects the measurement, processing and evaluating the obtained information seems necessary. Entrance the large amount of flood with suspended material and sedimentation, changes the soil properties gradually. In this study influence of flood spreading on soil mineralogy changes was evaluated after 10 years. In order to investigate the changes in flood spreading ditches, three rows between the spreading channels which had received the flood were chosen as the sampling sites. To investigate and identify the clay minerals of flood spreading area and compared with the control area near to flood spreading area, thirteen samples of 0-15cm soil horizon from three flood spreading rows and settling ditches were selected. The results obtained from X-ray diffraction curves showed the presence of palygorskite, Illite, chlorite, smectite and kaolinite in control area, three settling ditches and flood spreading rows. There was no difference between the types of clay minerals in control area with settling ditches and flood spreading rows but the amount of some clay minerals was different in these situations. It seems that the dry climate of region was the serious factor in no change of clay minerals. Flood spreading had little effect on types of clay minerals and just was able to change the amount of clay minerals in flood spreading rows.

Studying human and social dimension in the management of natural resources, including water resources has been accompanied by growth and development during past several decades. So, we require planning and policy making for the sustainable management of water resources for achieving human and ecological sustainability of water resources. Because of human and environmental components, managing the natural resources is very difficult and complicated. For effective management of water resources, cooperation of local beneficiaries is necessary. Accordingly, the social network analysis has been noted in the analysis of local stakeholders for sustainable management of water resources. The purpose of this study is social monitoring of local water beneficiaries network in Doroodzan watershed downstream using social network analysis. This analysis is based on trust and cooperation links and using quantitative and mathematical network indicators in macro-level. Based on the results, the density of local stakeholders of water resources in the relationship of trust and participation in the village of Kuh Sabz and Kare-Tawi was 68.8% and 66.2%, 60.1% and 55%, respectively, and the rate of reciprocity in these villages is 71.1% and 60.2%, respectively. . It is necessary to amplification social capital as main source of problem solving and sustainable water management realization.

An experiment was performed aimed to investigate the effects of priming and salinity on germination and seedling growth of Stipagrostis plumose in factorial test and completely randomized design with four replications in laboratory condition. The first factor was priming consist of salicylic acid with three levels (100, 200 and 300 mg/l), gibberellic acid with three levels (125, 250 and 500 ppm), ascorbic acid with three levels (100, 200 and 300 mg/l), and water as control, and the second factor was salinity treatment in six levels (0, 0.2, 0.4, 0.8, 1.2, 1.6 m/l). The measurement characteristics were speed of germination, percent of germination, root length, shoot length, seedling length and seed vigor. Results indicated that salt stress had inhibitive effect on germination and early seedling growth of S. plumosa. All chemical stimulators increased the germination characteristics of this plant. Also, the interaction of the tested treatments showed that gibberellic acid 250 ppm has the highest effect on improvement of germination characteristics under all levels of salinity stress. We conclude that priming seeds by gibberllic acid can increase resistance the germination of S. plumosa in areas prone to salinity.

All water quality indicators have a definite answer for the water quality of the stations. The use of fuzzy inference system has eliminated the limitation of the definiteness of the answers and the lack of consideration of the parameters of water quality determination from the standards. In this paper, data from 1990-89 in 12 stations in the upper and lower range, Mahabad Reservoir Dam, and seven parameters of turbidity, electrical conductivity, chemical oxygen requirement, biochemical required oxygen, total hardness, ammonium and phosphate, Used. All data were received from the Regional Water Authority of West Azerbaijan Province. MATLAB software has been used to perform analyzes. The Mamdani model has been used for water quality classification and triangular membership functions for model inputs and outputs. The input membership functions are three and the output membership functions are five. From the World Health Organization standard and existing standards for the quality of surface water resources in Iran to determine the desired, acceptable and unacceptable range for input parameters as well as the operator and to define the rules of use and with the help of fuzzy inference system of water quality index (FWQI) development given. The SW9 station is the most polluted and the SW6 station is the least polluted. The results show that the fuzzy index is appropriate in estimating surface water quality in the study area.

The study of soil seed bank provides vital information for rehabilitation and restoration of rangeland ecosystem. In the arid and semi-arid environments, shrub plants may cause accumulation of seed bank under their canopy, thereby protecting them against the livestock herbivory and the other environmental factors. This study was conducted with objective to investigate effect of Astragalus brachycalyx on composition of soil seeds bank, in two area of enclosure and under grazing. For this purpose, sampling of soil seed bank under the canopy of this species and its open space adjacent was measured using a flexible plot along the 100 meters transect. Soils were sampled from 0-5 and 5-10 cm depths. Then seed bank composition was identified after seed germination in glasshouse. The results showed that 16 species under the canopy of Astragalus brachycalyx and 12 plant species in the open space adjacent in enclosure area and 21 species under the canopy of Astragalus brachycalyx and 11 plant species in the open space adjacent in under grazing area. In the soil seed bank of an area under the livestock grazing and understory of Astragalus brachycalyx, the species namely Silene longipetala, Mentha longifolia, Veronica anagallis-aquatica and Anthemis odontostephana had the greatest numbers of seeds respectively. The area under livestock grazing had higher density of seed bank of plants with annual and perennial life, Therophytes and Hemicryptophytes biological forms, annual and perennial vegetative forms of forbs, and palatable classes II and III in understory compared to the open space.

Khorasan Razavi province has several rangeland species that their nutritive value is still unknown for the animal husbandman. Hence, this experiment was conducted to determine the nutritional potential of some range species containing Carthamus oxyacantha, Echinops ilicifolius, Silybum marianum, and Eremurus luteus (at the flowering stage) with a completely randomized design in 2019. The chemical-mineral compositions, gas production parameters, buffering capacity, and some ruminal fermentation parameters were determined in vitro. The lowest neutral detergent fiber (NDF, 16.41%), acid detergent fiber (ADF, 12.82%), acid detergent lignin (ADL, 5.52%), and crude fiber (CF, 17.63%) contents were obtained in Eremurus luteus (p < 0.0001). The highest crude protein (CP, 19.88%) and ash (21.69%) contents were observed in Silybum marianum (p < 0.0001). Higher calcium (Ca, 30.42 g/kg DM) content was observed in Eremurus luteus (p < 0.0001). The highest contents of nitrogen, potassium, sodium, magnesium, iron, zinc, manganese, and cobalt were related to Silybum marianum (p < 0.0001). Metabolizable energy (ME) ranged from 6.48 for Carthamus oxyacantha to 9.84 MJ/kg DM for Eremurus luteus. Eremurus luteus exhibited the highest (p < 0.0001) dry matter digestibility (DMD, 73.15%) and acid-base buffering capacity (213.05 mEq×10-3). The pH of the plant also ranged from 5.36 for Eremurus luteus to 6.05 for Echinops ilicifolius. The present study showed that each of the four rangeland species can easily meet part of the maintenance requirements of ruminants for nutrients and minerals. According to the measured parameters, Eremurus luteus had the highest nutritive value compared to the other plants.

Evaluations of the threatening factors to wetlands are necessary to sustain these ecosystems and improving them. The main goal was to identify and prioritize the factors threatening the Choghakhor wetland watershed. This research has been consisted of a cohort of 315 participants in an exploratory mixed method. Data analysis was performed by One-Sample T-Test and non-parametric Friedman Test. Factors threatening were evaluated and prioritized in four areas including: natural disasters, and biological, cultural and socio-economic threats. Living in the area, threats to this wetland are in an undesirable and unacceptable state. Likewise, the greatest impact is associated with the cultural threats and the biological threats obtaining the lowest priorities. In the field of cultural threats, a lack of coordination between government agencies in matters relating to the wetland with a mean score of 2.35. In the field of socio-economic threats, inter-basin water transfer from the Mount Sabzkouh to Choghakhor wetland with a mean score of 11.69; in terms of natural disasters, climate change and the melting of mountain glaciers with a mean score of 6.04; and, in the field of biological disasters, unauthorized grazing (over the production capacity of rangelands) have been recognized as the first priorities with a mean score of 2.29. As the final statements, it appears that cultural, followed by socio-economic threats are the most significant factors contributing to the destruction of this ecosystem. In the perspective of the participants, cultural and educational-based management could be the ideal solution for the current condition of the wetland.

Centaurea pabotii (CP), a range plant species from the Asteraceae family is endemic to Iran and mainly distributes in the wheat fields of southwest of Iran. A study was carried out to determine suitable habitats as well as habitat connectivity of this species in order to detect areas with high habitat connectivity in four provinces of Khuzestan, Bushehr, Fars and Kohgiluyeh and Boyer-Ahmad. Habitat suitability modelling was performed with 25 presence points of the CP and eight environmental layers, using Biomod2 package in the R software based on six species distribution models. The ensemble map resulting from these distribution models was used for habitat connectivity modelling using electrical-circuit method. Habitat suitability map of CP revealed that suitable habitats of this species were mainly located in the Khuzestan province. Elevation, annual precipitation and distance from agricultural lands, respectively, had the highest contribution in the model of habitat suitability of CP. Habitat connectivity modelling showed that the highest current density of movement was demonstrated in the north, east and southeast of Khuzestan, whereas the current density movement of southeast of Khuzestan was continued toward Kohgiluyeh and Boyer-Ahmad. However, current density of movement for CP in Bushehr and Fars provinces were detected isolated. Totally, wheat fields of Khuzestan province are more threatened by the invasion of CP and managers of Agriculture Jihad in Khuzestan province should take the necessary measures to protect wheat fields against the invasion of CP.

The government, like other people, has the power to own a property. Forests and Ranges became a national and public property owned by the government with the Ministerial act of the Nationalization of Forests. Government ownership of this property is to ensure that everyone should enjoys this asset and does not mean as specialized government property, but the principles of realizing and protecting state ownership of forests and ranges are not the same as the principles of realizing and protecting private property, so we see that the process of verifying and registration of government ownership of forests and ranges has its own specialized and technical dimensions, and on this basis, even if the principles and process of Document and Property Registration Law have not been followed, that is an Admissible Evidence in the judiciary as an official deeds. This change, in the case of the realization of state ownership over national range and forestlands with Definitive Recognition Deeds, is the result of years of legal disputes and contradict judgments in our country, which finally after decades, in 2005 as one of the most important changes, has resolved by the Supreme Court. Judgment of General Assembly of the Supreme Court is binding for all in any judicial and other authorities. Understanding this development and the causes of legal disputes and the basis of this approach are important for both jurists and scientists in the forest and rangeland sciences, as it clearly illustrates the Supreme Court's view of forest and rangeland Conservation

Measuring this year's growth is one of the basic requirements for calculating the annual storage potential of carbon. On the other hand, shrub plants, and especially Astragalus, are considered to be the most prominent and dominant species of semi-steppe rangelands. Therefore, the present study was conducted in June 2016, with the aim of estimating the growth of storage carbon in the Astragalus microcephalus plant and its relationship with the distance from the crisis center (overnight livestock area) in the Nazluchai mountain rangelands. For this purpose, Chir rangelands in the north of Noushin Shahr with an area of 1332 hectares, which in terms of vegetation, soil and topography, represents a level of various species in the region, were selected and six ecological sites were surveyed. Given that almost all of A.microcephalus species grow this year, it will become a woody organ; within each site, this year's growth of 30 A.microcephalus plant bases is intended to determine the organic carbon conversion factor and estimate the amount of carbon stored, it was cut off. After calculating the organic carbon conversion factor for biomass of plant bases on each site, multiplying it by the dry weight of this year's growth, the amount of organic carbon stored in the aerial parts was determined. By calculating the average carbon content in the bases and A.microcephalus species density, the amount of stored carbon per unit area of the habitat was calculated.

Watershed management practices have been implemented to avert land degradation and to enhance people's livelihoods in Iran for several years. The successes of these practices have been quite limited and the rates and intensities of adoption on local people haven’t identified. This study has been introduced an approach to consider some socioeconomic parameters from the stakeholders aspect which are important for watershed management decisions. Hasan abdal basin in Zanjan Province was selected as the case study area. The field data has completed with questionnaire instrument. The statistic population of this research was all 280 heads of families of stakeholders which living in this area. Among them, using Morgan table, 160 people were randomly asked questions directly. In this research, the Likert scale was used to analyze and measure the effects. The method of exploitation factor analysis was used to determine the factors. The validity of the questionnaire was calculated in KMO of 0.7 percent. The results of factor analysis indicated that effective parameters are in fore group's including improvement stakeholder participatory, flood control, reducing the migration and improving livelihoods. These fore factors, in general, had more than 67 percent of the total variance. The results showed that although watershed management projects in the region have been able to affect the four factors mentioned, but its manifestation in other aspects of life, such as improving the health of the village, the desire of villagers to stay in the region, improve income generation, reduce costs irrigation and dry farming crops have improved.

The aim of this study was to assess the regional effects of fire on the surface cover and soil characteristics of mountainous rangelands of Delfan County, Lorestan province, Iran. which seems has significant effect on vegetation characteristics on the study area. Four fire affected sites were selected for sampling and a close area without fire was considered as control. Sampling was carried out using random systematic method and the size of plots was determined using the minimal area framework. The number of plots was determined using statistical method. Totally, the data of eight sites including four fire affected sites and four control sites were measured during four consecutive years in early July of each year after fire. In each site, four transects of 50m length were selected in the direction of slope as well as perpendicular to the slope and five plots were established along each transect. Soils samples from the beginning, middle and end of each transect were taken from a depth of 0-30 cm. Independent t-test was used to compare the mean of the factors in two control and fire zones, and one-way ANOVA and Duncan test were used to compare the years. The results showed that fire caused a significant increase in forage production, cover percentage, perennial grasses density and forbes and percentage of litter cover. Also, the density and percentage of shrub species and bare soil cover decreased significantly. The fire caused an increase in organic matter, electrical conductivity, nitrogen, potassium, phosphorus and soil texture.

Study of the effect of woody plant species on the production, diversity and richness of substratum herbaceous species, especially in the arid and semiarid regions, is essential for the proper management of these ecosystems. Therefore, the rangelands of Chenarnaz region in Khatam city in Yazd province were selected and then, using 0.5m×0.5m quadrats, vegetation sampling was performed under the selected 15 sites from Daphne mezerum, Amygdalus scoparia and Ebenus stellate (growing in equal topographical conditions) canopies, and outside of the canopies (as control). In each quadrat, the cover percentage of each plant species was visually estimated and the productions were measured by clipping and weighing method. The species diversity and richness indices were calculated using Past software through introducing the plant covers into the software. The results showed that the most values of Shannon-Weaner and Simpson diversity indices were found under A. scoparia (2.07 and 0.80, respectively) and the lowest values were found under E. stellata (1.010 and 055, respectively). In addition, the highest values of Menhinik and Margalef richness indices were found under A. scoparia (4.90 and 3.43, respectively) and D. mezerum (4.25 and 3.12, respectively), while the highest production was found under E. stellata (64.76 g/m2). The results of this study showed that different woody species had the desired but different effects on the herbaceous species, in such, A. scoparia and D. mezerum had significant positive effects on species diversity and E. stellata increased significantly species production; therefore, conservation of all woody species is emphasized in the region.