Improving seed germination rate accelerates early seedling establishment, in turn, enhances plant growth and forage production in rangelands and pastures. Rapid and simultaneous germination of seeds leads to successful plant establishment. The ingoing research aims to deals with effect of SiO2 nanoparticles at concentrations of 0, 5, 20, 40, 60 and 80 mg/l on seed germination rate in Astragalus squarrosus. The experiment was conducted for 15 days under constant temperature of 20 °C, 16 h of light and 8 hours dark. The treatments were arranged as factorial based on a completely randomized design with four replicates in Department of Natural Resources at the Ferdowsi University of Mashhad, Iran. The results of experiment showed that the germination percentage of scarified seeds treated with SiO2 nanoparticles with 40ppm concentration was improved compared to control seeds and non-scarified ones treated with nanoparticles. At the same time, some other positive effects of other nanoparticle concentrations on germination rate and percent were obvious so that the effect of different concentrations of nanoparticles on seed germination traits Astragalus squarrosus was found to be significant. The highest and lowest germination percentage was recorded under concentration of 40 ppm and 80 ppm those seeds treated with nanoparticles, respectively. As SiO2 concentration increased, no enhancing positive effect on seed germination attributes of Astragalus squarrosus was found. In this experiment, it was found that seeds scarified and treated with 40 or 60 mg/l of SiO2 nanoparticles showed improved germination in Astragalus squarrosus , so this treatment can be promising for establishment and colonization of this species in natural landscapes. تفاصيل المقالة

Interrupting the processes which control ecosystem resources has dramatic impacts on the rangeland conditions. To protect ecosystems and landscape, it needs to understand the ecosystem processes which regulate the ecosystem resources. As main components of ecosystems, patches and inter-patches play important roles in energy and materials cascade. Ecologically, functional parameters such as stability, infiltration and nutrient cycling serve as key factors determining the movement of sediments, nutrients and organic matter as well. The present research aims to evaluate and compare the ecological patches of grasses, shrubs and mixed grasses- shrub using indices of stability, infiltration and nutrient cycling. Therefore, sampling was carried out in Qahavand rangelands located in the south east of Hamadan province, Iran on three patches of grass (Cynodon dactylon), shrub (Camphorosma monspeliaca L. and Astragalus microcephalus) and mixed grasses-shrub (Camphorosma monspeliaca + Cynodon dactylon) to evaluate the aforementioned parameters. Samples were taken along three 50 m transects using LFA (Landscape Function Analysis) method. Three indices of stability, infiltration and nutrient cycling and their individual contributions on the whole ecosystems' functions were determined. Results showed that all three patches vary significantly in function so that the mixed patch (Camphorosma monspeliaca + Cynodon dactylon) may be accounted for the highest values among the others. The study area had a good level of stability and nutrient cycling while infiltration rate was moderate mainly due to much proportion of clay in soil texture. Somehow, results of soil profile study in the area imply good stability and moderate infiltration. تفاصيل المقالة

Abstract. From the perspectives of many environmental and conservative policy makers, improving and diversifying the livelihoods have been found as a mechanism to promote the livelihoods and persuade people to avoid the overexploitation and degradation of natural resources. Due to the fragility of the environment and inconsistency of incomes, the alternative income sources may be promised to warrant inhabitant's earnings. The noticeable example for this is arid and desert area in central and eastern Iran. This paper presents the conceptual underpinnings of this method with some examples of how innovative ways for creating livelihoods can help alleviate the pressure on marginal arid lands. Three case studies put forwarded considering activities undertaken within an integrated international project formwork called sustainable management in marginal dry lands. At first, introduction of chicken farming to farmers in Hunshundake Sand land in northern China has minimized pressure on grasslands and led to the restoration of these ecosystems. Secondly, to develop desert-based farming on the edge of Cholistan desert in Pakistan has provided a new income source for rural people. Thirdly, the development of a new income-generating activity in terms of soap production from olive in Dana Biosphere Reserve in Jordan has proved that traditional olive farming can be associated with community-based initiatives to create a market for goods and commodities. Also the conditions for introduction of similar alternative approaches to Iran are evaluated through evaluating existing socioeconomic and climatic backgrounds. Collaboration with communities for creating new and sustainable ways to reduce pressure on the land in arid and marginal desert areas can be a powerful tool to overcome poverty and struggle desertification and its resiliency. تفاصيل المقالة