مجله پژوهشهای راهبردی در علوم کشاورزی و منابع طبیعی
سال هشتم شماره 2 (پاییز و زمستان 1402)

The onions produced in centeral and northern regions of Iran are consumed in autumn and mid winter, and after that, there is a shortage of onions in the market. This shortage can be eliminated by onion production in mid winter in the southern regions of Iran. Short day, early maturity, tolerance to environmental stresses and high yielding are characters of cultivars, that are recommended for onion production in southern regions of Iran. Although many onion landraces are observed in southern region of Iran, however due to low yielding of these landraces, foreign cultivars such as Texas early grano, Texas early white, Primavera and Saba are cultivated in the most part of these regions. Recommended sowing seed and transplants as well as sets transplanting dates varied from early October to mid September depended on climatic conditions, planting methods, season production and genotypes. Application of Zn-Amino celates (specially methionine-Zn) increased yield, pungency, storability and decreased nitrate accumulation in improved population of Behbahan onion and Primavera cultivar. In intercropping of onion and lettuce as well as fenugreek yield, land equivalent ratio and income equivalent ratio were higher than sole crop. Ramhormoz genotype is relative resistance to thrips. Pendimetalin, Focus, Select, Gallent-Super and Oxyfluorofen herbicides control weeds in onion farms. Resistance inducers can be used as a substitute for fungicide application to control downy mildew in onion. The storability of improved population of Behbahan onion , Texas early grano as well as Seba cultivars are high.

Ensuring food security is one of the most important global concerns of national and global policies. The agriculture is important sector in the country economy due to the supply of food for society, and appropriate developmental measures must be taken to ensure the sustainable security of this sector. On the other hand, agricultural production has a significant impact on the environment. Therefore, it is necessary to provide people's food basket while maintaining the principles of sustainability with minimal environmental effects. In this study, the life cycle assessment method was used to evaluate the environmental effects of the Iranian food basket. The investigated products in this basket included: red meat, white meat, rice, milk, vegetable oil, eggs, potatoes, onions, wheat, sugar, beans, oranges, apples, tea, tomatoes and vegetables. The results showed that the biggest environmental burden is related to animal products (chicken and beef, respectively), followed by the production of wheat, which is consumed in the form of bread and pasta in the food basket. Edible oil is also in the next place. After identifying the products with high environmental load, two strategies have been presented to reduce the environmental effects. First, changing the food basket and forming an optimal food basket by considering environmental issues, and the second, increasing the efficiency of production systems and reducing the waste at different stages of the supply chain it is then up to policymakers to provide the bases for practical measures.

This research was conducted with the aim of evaluating the development level of the hatchery industry in Iran at two points in 2016 and 2021. The effective criteria in the development of the hatchery industry were investigated, then the weights of the criteria were estimated using Shannon entropy and pairwise comparisons methods as follows. The number of hatchery institutions (0.461), the capacity of hatchery machines (0.243), the number of day-old chicks produced (0.148), the number of fertilized eggs consumed (0.094) and the number of workers in the hatchery industry (0.052). These criteria were used in the TOPSIS method to rank the top 11 provinces. The results showed that in 2016, Mazandaran, Guilan and East Azarbaijan provinces and in 2021, Guilan, Mazandaran and Golestan provinces had the highest development level in this industry. Developmental level of hatchery industry did not show a significan correlation with the state of broiler breeding and production industries as upstream and downstream industries.

The phenomenon of woody plant encroachment (WPE) has been recognized as a global example of the transition and change in vegetation composition, which occurs in grasslands and rangeland ecosystems around the world. Considering the scope of this phenomenon and its impacts on the ecological services and the livelihood of millions of local people, it is necessary to investigate the factors and contexts of the phenomenon emergence. By reviewing related studies of the phenomenon in natural ecosystems, this paper examines and recognizes the factors and effective areas and contexts of its emergence. In general, the summary of the research showed that long-term factors such as climate, soil and human management and short-term factors including climate fluctuations and human activities affect WPE, the dynamics of woody plants and the species composition of each region. In addition, at the local level, changes in the amount and type of precipitation, herbivory, types of fires, and soil characteristics affect the probability of the abundance of woody plants and the WPE phenomenon. This research suggests that future research should examine and identify a combination of traits of woody plants needed to cross all obstacles and stages of WPE, this will help to explain the WPE phenomenon in the past and its prediction in the future.

This study, by reviewing the findings related to this phenomenon in natural ecosystems, investigates and recognizes the effective factors and contexts of emergence, has dealt with this phenomenon.

The causes and factors of the WPE are still something like a puzzle, and several stimuli may interact and intensify the occurrence of this phenomenon. Therefore, understanding the phenomenon of WPE requires considering multiple interactions between stimulating and limiting factors and their changes over time in a specific location. There is uncertainty in quantifying the importance of these stimuli and understanding their interaction with each other. In general, the WPE is affected by long-term (such as climate and carbon dioxide concentration) and short-term (such as fire and herbivory) driving factors that affect the dynamics of woody plant cover and the

The mortality of forest species, especially in arid and semi-arid regions, has been considered the main challenge of diverse ecosystems. The aim of this study was to compare the mortality status of Iranian oak and Mt. Atlas mastic tree in the Zagros forests in western Iran. To carry out this study, whole forests in the Gilan-e Gharb were considered. For this purpose, the entire surface was divided into equal parts with a sampling grid of 3000 x 3000 m2. Ninety two sample plots with an area of 0.25 ha considered for sampling at the intersection of the lines in the forests. Sampling of all the were trees in the plots was done 100%. Based on objective observations, the ratio of dried branches to the whole tree branches was used to determine the dryness ratio of the studied trees. The results showed that the frequency of 1st mortality in different species shows that its highest frequency is 83.4% in Iranian oak (Quercus brantii Lindl.). Other species in the region, such as Prunus lycioides C.K.Schneid., Pistacia atlantica mutica Desf., Acer monspessulanum L., and Crataegus sp. L., had 5.1%, 4.4%, 3.2%, and 2% of 1st mortality, respectively. The frequency of 2nd mortality in Persian oak was 84.4% and in other species in the region, such as P.atlantica, Crataegus sp, and P.lycioides C.K.Schneid., it was 9.8%, 2.25%, and 2%, respectively. Similarly, the highest frequency of trees with mortality grade 5 included Iranian oak,  P. atlantica mutica Desf., and P. lycioides C.K.Schneid. species with 94.2%, 2.8%, and 2.6%, respectively. From the total population of Persian oaks, 28% of them were healthy and 72% of them were dying in various degrees. In the wild plum species, 83% of the trees were healthy and 17% were dying. Furthermore, in the wild pistachio species, 23% of the trees were alive and healthy and 77% of them were dead. Based on the results, supporting measures will include monitoring the structure of stands for better protection of forests, maintaining the mix of stands and stimulating structural complexity and heterogeneity, that are valuable tools to reduce the risks associated with increasing tree dieback, and other new disturbance regimes in line with the resilience strategy.

Currently, the agricultural food supply chain is facing many challenges including the increase in the diversity of consumer demand, quality, product safety, and unsustainable growth, as well as many challenges including environmental, economic, and social concerns. Despite its importance, unfortunately, until now, there has been very little coherent and coordinated research on identifying and solving the challenges in this field. On the other hand, a wide range of indicators for monitoring and evaluating sustainability issues in the field of agri-food are seen sporadically, but a few of them are specifically related to this field. Therefore, this research aimed to provide a model of effective indicators of the sustainable supply chain of agricultural food and to increase attention to the research results obtained using a systematic review approach. To identify accurately the indicators by searching in the databases, 74 articles in the field of the sustainable supply chain of food and agriculture were reviewed separately. Finally, 40 articles were selected until the beginning of 2023 and analyzed to reveal the prospects and research gaps in this field. Previous studies have focused individually on the aspects of identification, safety food safety, and performance evaluation, but the simultaneous examination of the supply chain of agricultural food sustainability with other indicators involved in this field has rarely been investigated. The main category of key performance criteria and indicators (i.e. efficiency, flexibility, responsiveness, product quality, and reliability) have been identified as effective indicators in this field. A new concept for evaluating and identifying indicators, chain challenges provide an agricultural food supply that includes sustainability indicators and other relevant indicators along with special indicators.