Journal of Rangeland Science
Volume:14 Issue: 1, Winter 2023

Understanding the relationship between biomass production and forage quality will help to use the selected cultivar and to optimize the cutting interval between harvests in forages to get the required biomass with the desired quality. Among potential forage grasses that required this knowledge, there were Sudan grass cultivars. The aim of the present work was to investigate the forage yield and quality traits of five Sudan grass cultivars with three harvest days intervals at G/Zuria and W/Dembia districts in 2019 and 2020. Five Sudan grass cultivars (DRLME, Mezrut, Wichello, Michello and Aden) and three harvest schedules (40, 50 and 60 days interval) were combined and used for the study. A factorial experiment was laid down in a completely Randomized Block Design (RCBD) with four replications. To assess their potential plant height (cm), number of tillers per plant, forage fresh yield, Dry Matter (DM) yield, Leaf to Stem Ratio (LSR), Crude Protein (CP) yield and quality traits including total ash, Crude Protein (CP), Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF) and Acid Detergent Lignin (ADL) were recorded. Data were analyzed of variance, and when the difference was significant, the treatment means were compared using the LSD test at 5%. The result revealed that there were significant differences between cultivars for all the traits except LRS, NDF, ADF and ADL (P < 0.05). The Drlme and Aden cultivars with average values of 82.44 and 80.03 cm respectively had higher plant height than the other (P < 0.05). For tiller number, Wichello and Mezrut with values of 17.08 and 15.47, respectively had higher density. The higher annual fresh biomass yield with average values of 28.65 and 26.77 tha−1 were obtained in Mezrut and Drlme, respectively. Drlme and Michello with values of 6.61 and 6.95 tha−1 produced maximum annual forage DM yield. For CP% and CP yield, the Cultivars Mezrut, Michello and Wichello were found efficient in total CP yield. There were significant differences between harvest days interval for all the traits except tiller number (P < 0.05). The higher values of plant height, forage fresh and dry yield and CP yield were observed in 60 days cutting interval. It was concluded that Mezrut, Wichello and Michello at 60 days interval cutting had higher CP yields and were recommended for further Sudan grass production.

The experiment was conducted in 2018 cropping season with the objective of evaluating the effects of harvesting stage and seed rate on agronomic performance and quality traits of Rhodes grass (Chloris gayana K.) grown in northwestern Ethiopia under rain fed conditions. A factorial experiment was conducted using two factors of main factor harvesting stages in three levels (60, 90 and 120 day) and the sub factor of seed rate in three levels (5, 10 and 15 kg/ha) using a Randomized Complete Block Design (RCBD) with three replications. Data were collected for morphological traits such as plant height, tillers number, leaf length, leaf number per plant and quality traits such as Crude Protein (CP%), total ash, Acid Detergent Fiber (ADF%), Neutral Detergent Fiber (NDF%) and Acid Detergent Lignin (ADL%). The data were subjected to ANOVA using SAS software. Results showed significant effects of seed rate by harvesting stage interaction on all plant morphological traits, DM yield and quality traits (P < 0.05). As the seed rate and harvesting stage increased, there was an increase in tiller number, leaf length, plant height, NDF and ADL and ADF%. There were significant (P < 0.05) increments in DM yield as the result of descending seed rate and advanced maturity. Also, CP and total ash were markedly decreased as the harvesting stages were increased. It could be concluded that both seed rate and harvesting stage are important agronomic practices in Rhodes grass production; hence, 90 days harvesting stage and lower level of seed rate (5 kg/ha) are recommended for better yield and quality traits of Rhodes grass.

Measurement of Technical Efficiency (TE) provides useful information on the competitiveness of Rangeland Unit (RU) and potential to improve productivity, with the existing resources. So, the purpose of this study was to evaluate the technical efficiency of Traditional Livestock Husbandry (TLH) and determine the main factors influencing it via management variables of Range Management Plans (RMP) and demographic variables of ranchers (age, education, herd size) in the semi-arid rangelands of Northern Iran. To do this, the study employs a Data Envelopment Analysis (DEA) via parametric stochastic frontier analysis. This technique creates efficiency indices by comparing the performance of traditional livestock husbandry. The random sampling method was used to collect data via a survey questionnaire from 82 semi-nomad ranchers in 2018 – 2019. Results show that the average value of scale efficiency (SE) was 0.78; technical efficiency (TE) at Constant Returns to Scale (TECRS) and Variable Returns to Scale (TEVRS) level were calculated 0.54 and 0.69, respectively. Also, implementing RMP in some RUs could improve SE level by 0.81. Over 62.2% of animal units show increasing returns to scale and about a quarter to a fifth of the animal units were in the area of risk-reducing returns which indicates the need to reduce the scale to improve efficiency. Therefore; a significant part of technical efficiency is related to the SE and in the current research, implementing RMP in rangeland units improved the SE up to 81%. This ratio of RMP-in was less than RMP-out which showed the need to increase returns to scale to improve efficiency. About 10% of animal units in implementing RMPs allocated to perfectly efficient and so-called are on the boundary function. The Tobit regression results indicated that education, experience, livestock breed and implantation of RMP significantly affected the efficiency. Policies are thus needed to improve the mentioned above factors to sustain the efficiency of RUs that diversify the rancher’s economy.

The Leguminosae family plays a significant role in rangeland ecosystems with biological nitrogen fixation for soil fertility. The grasses significantly increase rangeland production and sustainability. Legume-Grass Ratio (LGR) is an indicator of soil fertility. This study was aimed to investigate the LGR and some soil properties in four vegetation types (Stipa arabica Trin.-Medicago sativa L., Festuca ovina L.-Astragalus gossypinus Fisc., Artemisia sieber Besser-Festuca ovina and Artemisia sieberi) in the Peshert rangeland, Chahardangeh Sari, Iran in 2020. In this research, 40 plots of 1m2 were randomly established in four vegetation types. In each plot, vegetation characteristics including the number of species per unit area were recorded. Soil sampling was done at a depth of 0 – 20 cm for each plot. Finally, 40 soil samples were analysed in the laboratory for soil properties including: Carbon (C), Soil Organic Matter (SOM), Bulk Density (BD), Aggregate Stability (AS), Particulate Organic Matter (POM), soil texture, available potassium (K), Nitrogen (N), EC and pH, available Phosphorus (P) and carbon to nitrogen ratio. Data were analyzed using one-way ANOVA and Duncan’s test was used to compare the differences between four vegetation types for LGR, species diversity and soil properties. SPSS-v20 software was used for data analysis. The results showed that there were significant differences between four vegetation types for all the traits (P ≤ 0.05). The highest and lowest LGR with average values of 0.86 and 0.10 were observed in S. arabica-M. sativa and Ar. sieberi-F. ovina, respectively. The lowest amounts of AS%, SOM%, N% and POM% with average values of 0.31, 0.62, 0.03, 3.53 were observed in Ar. sieberi. In all vegetation types, soil fertility decreased by decreasing the LGR.

Vegetation is an important component of terrestrial ecosystems whose changes are controlled by climate changes and human activities. In order to detect the climate change impact on vegetation dynamics of Kermanshah province, Iran, this study was conducted using multi-time images of NDVI and EVI regarded as vegetation indices taken by MODIS sensors. Also, the trend of changes in climatic parameters such as temperature and precipitation were used by Mann-Kendall test over 15 years (2006 – 2020). Finally, the correlation between vegetation and climatic parameters was examined. The result of 15-year changes in vegetation using two indicators of NDVI and EVI showed that the trend of vegetation in more than 59% of Kermanshah province has been decreasing. The trend of precipitation in more than 88% had decreased and the trend of temperature in the 98% area had increased. The correlation between vegetation obtained from NDVI and EVI indices with the climatic parameter showed a positive correlation between precipitation and vegetation and a negative correlation between temperature and vegetation in more than 80% and 59% of this province, respectively. The results of the correlation analysis of different land-uses showed that in the barren lands and shrub lands, the positive correlations between precipitation and vegetation were stronger than the negative correlation between temperature and vegetation. In contrast, in grasslands and savannahs, the relationship between vegetation and temperature was stronger than that for precipitation. According to the results of this study, the climate changes and human activities are effective in controlling the trend of vegetation in different areas, which can be well demonstrated using the information obtained from remote sensing data.

Wildfires annually occur as a threatening factor in natural resources at a large scale. This study was conducted with the aim of determining the effects of fire on the structural and functional characteristics of vegetation in the Kaboudeh range site, Kermanshah province, Iran during three years (2018-2020). An unburned range (control) was selected near the burned range. Both sites had the same characteristics. Sampling was preformed at a stratified random with four 50 m transects and 20 m distances as well as 10 fixed quadrates (1 m2). The spatial correlation was performed between quadrates.Data were collected for plant density (no/m2), canopy cover (%), and production (g/cm) for species and palatability classes. The range condition and range trend were evaluated using four factors and balance methods. The results showed that the palatable plants in the fire site were decreased with density (1.7 no/m2), production (4.1 g/m2), and canopy cover (3.9 %) compared to the control. In the first years after the fire, the fire decreased the number of palatable plants, and decreased the average values of production and canopy cover both by approximately 75%, butthe class II plants had not significantly decreased.In the burned site, the invasive plants (Class III), dominated by annual grasses, have spread rapidly across the range.The range condition in the burned area was poor andrange condition trend was positive, but in the control area,range condition was medium and range condition trendwas constant.In the short term, fire drastically caused the increase of annual grasses,decrease of species diversity, and subsequentlyled to a decrease in the stability of the range.

The basis of many plant studies is the identification of plant species because identifying plant populations in every region is the pivotal pillar of plants conservation. Furthermore, study of the stages of plant growth cycle is one of the ways to determine growth details of any given plant. The current research aimed to investigate the phenological stages of Iris ferdowsii in the main habitat of the plant based on the BBCH system for the first time (Biologische Bundesanstalt Bundessortenamt and Chemical Industry). The phenological study of Iris ferdowsii was performed during three consecutive years from 2018 to 2021. After selecting the habitat of this plant species, 10 different points of plant growth with a certain distance from each other were selected to study the different phenological stages of Iris ferdowsii. According to this system, the phenological stages of Iris ferdowsii was divided into 7 main stages and 13 sub-stages including: emergence, growth and development of two leaves, full growth and development of leaves, spathes stage, flowering, flower wilting, seed capsule formation, splitting of the seed capsule, the beginning of summer dormancy, the end of summer dormancy, the fall growth, the beginning of winter quiescence, and the end of winter quiescence. Identifying the new and endangered plant species of Iris ferdowsii, as a wild plant and a new genetic source provides researchers with the proper planning to preserve this species, domesticate and use it properly in breeding programs. We can also study its potentials in various ornamental and medicinal fields.

Nowadays, in many rangelands, due to overgrazing and climate change, the plant germination and establishment are greatly reduced. This study was carried out to investigate the effects of seed dormancy breaking treatments on Bunium luristanicum germination (in winter 2021). Seeds of B. luristanicum were subjected to 16 dormancy breaking treatments using a completely randomized design (CRD) with five replications. Result showed that gibberellic acid (GA3) + hot water (70 ◦C) and GA3 + H2SO4 (50%) with average values of 80% and 82% had the highest germination percent, respectively. Seed scarification with hot water was better than sulfuric acid because acid increased abnormal seedling number. The highest seedling weight with values of 16.9 and 14.9 mg were recorded in the treatments of GA3 + sulfuric acid 50% and GA3 + hot water 70 ◦C, respectively. The highest abnormal seedling was obtained in combination of sulfuric acid 75% with other treatments. The highest seed vigor index was obtained in seeds treated with GA3 (500 ppm) + hot water 70 ◦C. Results indicated seeds scarification with hot water 70 ◦C (10 min) followed by soaking in GA3 (500 ppm) for 12 hours was the best treatment for seed dormancy breaking, and improved seedling growth of B. luristanicum.

In order to investigate the effect of contour furrow on the vegetation and soil characteristics, a study was conducted at Bolbol rangelands, Ashkazar, Yazd Province, Iran in 2020. The implementation of contour furrow was done previously at the rangeland in the area of 100 ha in 2006. Data were collected at both contour furrow site and outside it (control site). At each site, four transects (300m) were established at the distance of 100m from each other. Along each transect, 15 plots (2m2) were established at a distance of 12m from each other. At each plot, the vegetation characteristics (vegetation percent, richness and diversity of species, Artemisia sieberi canopy cover) and soil characteristics (soil permeability, soil moisture and carbon stabilization) were measured. The obtained data of sites were compared using independent T test. According to the results, the vegetation percent and canopy cover of Artemisia sieberi increased by 29.5% and 47.7% than that for control, respectively (p ≤ 0.01). The effect of contour furrow on species diversity index was significant (p ≤ 0.05) and the diversity index was increased by 23% than that for control. The soil moisture was compared in both sites in May, August and November. Result showed that soil moisture increased by 66.4% (p ≤ 0.01) in May. An increase of 12.5% of carbon storage was observed in the soil at the contour furrow site as compared to the control site (p ≤ 0.01). It was concluded that the implementation of contour furrow coupled with planting of Artemisia sieberi was successful in combating desertification in this research area.