JOURNAL OF RANGELAND SCIENCE
Year:2020 | Volume:10 | Issue:2|Papers Count:8

The study was conducted to determine the plants preference by goats grazing at Central Darfur State, Sudan in 2016. The objective was to identify desirable plants that would assist in range rehabilitation. Five mature female goats were used to determine diet selection using the bite count technique. The total number of bites from each plant species was recorded and the selected diet and preference indices were calculated. It was found that forbs constituted 52. 6% of the diet of goats followed by trees and shrubs (43. 6%) and then grasses (3. 6%). Among the forbs, Ipomoea sinensis (Desr. ), Kohautia aspera and Haemanthus multiflorus were the most selected forbs with average values of 7. 17%, 5. 53% and 4. 06%, respectively. Faidherbia albida, Ziziphus spina-christi and Albizia amara were the most selected trees with average values of 18. 29%, 7. 77% and 7. 66%, respectively. The grass species that appeared most in the diet of goats was Pennisetum pedicellatum (3. 53%). In this study, forbs had higher Relative Preference Indices (RPI) than grasses. The higher values of RPI in forbs as Abelmoschus esculentus, Kohautia aspera, Commelina kotschyi, Portulaca quadrifida, Talinum portulacifolium and Setaria acromelaena were 25. 2 7. 9, 3. 7, 3. 68, 3. 64 and 3. 42, respectively. Plants with higher RPI were suggested for reseeding rehabilitation projects. These findings may be considered as a basis for an informed management system in the study area which will be invaluable in developing sustainable management strategies.

Investigation of the relationship between plant species and environmental factors plays an important role in plant ecology. The present study aimed to develop the best predicting model for distribution of Prangos uloptera DC. using Logistic Regression (LR) and Maximum Entropy Methods (MaxEnt) in its habitat in the southern rangeland of Ardabil province, Iran. Vegetation data (presence and absence of P. uloptera) and environmental factors (including soil, topography and climatic variables) were collected. The original vegetation type map was prepared using slope and elevation maps (1: 25000 scale) and satellite imagery (Landsat). Vegetation samples were collected in 2016. In each site, three transects of 100 m length were deployed (two transects in the direction of a gradient and one transect perpendicular to the slope direction). On each transect, ten 4m2 plots were placed along each transect, and the total canopy cover and plant density were recorded. Overall, 180 plots were sampled in six sites. Soil samples were collected at a depth of 0-30 cm at the beginning and end of each transect. The LR method was performed in the SPSS Ver. 19 software, and the Maximum Entropy method was carried out in the MaxEnt Ver. 3. 1 software. The LR model showed that rainfall had the highest effect on the distribution of the P. uloptera habitat. The accuracy of the LR method for the prediction map was good (Kappa index= 0. 65). The MaxEnt method showed that variables including sand, Nitrogen (N), silt, and potassium (K) had the highest effect on distribution of P. uloptera habitat. However, the accuracy of the MaxEnt method was low (Kappa index=0. 35). It was concluded that modeling methods could be used as a prediction tool to determine the location of plant species. This may lead to better rangelands management and improvement in areas with similar conditions.

This study was conducted at Eldebeibat area in South Kordofan State, Sudan. The aim of this study was to assess the role of competition on rangelands utilization in the occurrence of conflicts between land users in the semi-arid areas of Eldebeibat, Sudan. Two target questionnaires were designed to collect data from two groups of land users namely nomadic pastoralists and sedentary farmers that are using the area. The data were analyzed using Statistical Package for Social Science (SPSS). The results showed that illiteracy was high in both groups. The crop production was the main source of income in the sedentary communities while pastoralists practiced cultivation beside livestock rising at the same time. However, both groups preferred raising mixed species of livestock in their herd structure. In addition, it was found that milk production represented the main goal of livestock keeping for the both groups. The results also indicated that the main reason of the livestock health deterioration was shortage of forage. Moreover, pastoralists followed the restricted routes to practice grazing. All respondents included in this study considered the occurrence of conflicts among them as a normal phenomenon and the causes of conflicts are different between them. Most of the nomad pastoralists considered blockage of routes of livestock movement by farms as the main cause of conflicts whereas sedentary groups attributed the occurrence of conflicts for damaging their farms by pastoralists’ livestock for entrance to and exit from grazing land and during grazing that was increased during rainy seasons in particular. The two groups resort to traditional local administration (Godeyah) for reconciliation and solving the conflicts among them.

Understanding ecological processes is a prerequisite for the management of rangelands; therefore, recognition of the relationship between environmental factors and vegetation is very important. The present research aims to investigate environmental and management factors affecting rangeland vegetation distribution in Saral rangelands of Kurdistan province, Iran, in 2017. Sampling was done in eight vegetation types along four 300 m transects. Fifteen 1m2 plots established along each transect in 20 m distances. Ten soil samples along transects were taken according to the plants root depth in the average depth 0-50 cm in 10 profiles within each vegetation type. Various environmental factors such as topographic factors (slope, aspect, and elevation), soil physical properties (depths, soil texture, gravel, and saturation moisture) and various chemical factors such as acidity, electrical conductivity, lime, gypsum, nitrogen, phosphor, and potassium were measured and grazing intensity considered and measured as managerial factor. The collected data were subjected to Principal Component Analysis (PCA) and the important factors affecting plant community distribution were determined. According to the results, first and second components account for 39. 29% and 26. 28% of community distribution, respectively. The results showed that among various environmental and grazing factors affecting plant distribution, soil texture, soil depth, grazing intensity, elevation, potassium and gravel had the most significant effects on present plant community distribution in studied rangeland. Silt, gravel and grazing intensity play important roles in the spatial distribution of vegetation communities, respectively.

The present study focuses on the past (1985) and current (2018) status of the Naama’ s Sabkha, particularly its salinity, vegetation, and water status. The acquired results will be useful for the preservation of Sabkha biodiversity. The representative sampling allowed us to make 136 soil samples over two depths: topsoil (0-4 cm) and down soil (4-30 cm) layers. The salinity analyses revealed that the maximum values are 115. 3 g/l at 4 cm and 80. 3 g/l at 30 cm depths. Regarding the soil conductivity, the highest values recorded at 4 cm and 30 cm are 198. 4 mS. cm-1 and 141. 89 mS. cm-1, respectively. At the same time, the results highlight that the Sabkha soil is weakly alkaline with strongly alkaline. The diachronic study based on the NDVI analysis of the Landsat_5, Landsat_8, and Sentinel_2 satellite imagery showed the installation of varied vegetation during 33 years. The outcomes of the statistical analysis of NDVI1985 and NDVI2018 (p<0. 01, R2=0. 77) show a significant development of vegetation. The use of NDWI for the period (1985 to 2018) highlights the importance of the water deficit in the region (p<0. 01, R2=0. 72). The results of the imagery geostatistical treatments reveal the changes which have occurred in particular the increase in the area of Sabkha, which was 431ha in 1985 to 514 ha in 2018. This is an increase of 83 ha for 33 years (2. 5 ha per year). In other words, there was an evolution of 19. 25% compared to the area in 1985.

The chemical composition and digestibility of twelve plant samples (Arthrocnemum macrostachyum, Atriplex canescens, Artemesia herba-alba, Astragalus gombo, Calobota saharae Ceratonia siliqua, Gleditsia triacanthos, Hedysarum coronarium, Medicago sativa, Ononis natrix L, Hordeum vulgare and Stipa tenacissima L. ) grown in arid and semi-arid areas of Algeria were evaluated (in 2010). Feed components were determined by proximate analysis whereas phenolic and tannin compounds were analyzed by colorimetric procedures. Digestibility was assessed by conventional gravimetric in vitro and in situ methods. In general, crude protein content in dicotyledon (dicots) species was always greater than that in monocotyledon (monocots) grass showing higher Neutral and Acid Detergent Fiber (NDF and ADF) and lower lignin contents than dicots. The tannin concentration varied considerably between species, but in general, the plants investigated in this study had low tannin contents (except for Ceratonia siliqua, Gleditsia triacanthos and Hedysarum coronarium). Monocots showed lower in vitro and in situ, fermentation rate and cumulative gas production than dicots species. This study indicated that a large reserve of plant species in the local flora is available that could be potentially used for livestock feeding. These feeds, if fully exploited, could assist in increasing the level of production and productivity of the livestock resources in the region.

The assessment of relationships between satellite-derived vegetation indices and meteorological drought improves our understanding of how these indices respond to climatic changes. The combination of climate data and the Normalized Difference Vegetation Index (NDVI) product of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery provided an opportunity to evaluate the impact of drought on land degradation over the growing seasons. The main goal of this study was to investigate the effect of drought on vegetation degradation in Meyghan plain, Arak, Iran. For this purpose, climatic and satellite data were used. The annual Standardized Precipitation Index (SPI) was calculated for 20 years (1998-2017). Then, the NDVI maps were classified into three classes according to the Tokunaga-Thug method. These classes are: Class 1) no vegetation; class 2) low-density or poor rangelands, and class 3) semi-dense and dense vegetation cover such as agricultural lands. The relationship between the percentage of vegetation cover classes (classes 2 and 3) and the drought index of the previous year was assessed using the Pearson correlation test. The results showed that the correlation between these variables was significantly dependent on vegetation degradation in the poor vegetation area (R=0. 51; P-value<0. 05). In contrast, there was a negative significant relationship between drought and the percentage of dense areas of vegetation (R=-0. 46; P-value<0. 06). Hence, it was concluded that the sensitivity of the low-density area (poor rangeland) to drought was more than dense vegetation covers (agricultural lands). Its reason is that the most important source of water supply for natural rangelands is the atmospheric precipitation that has been reduced due to the occurrence of droughts in recent years.

Soil microbial biomass plays an important role in nutrient transformation in terrestrial ecosystems. Microbial biomass is also an early indicator of changes in total soil organic carbon. Thus, the main objective of this study was to identify and quantify the present status of soil microbial biomass carbon and nitrogen with various management practices in Himalayan rangeland. To meet the aforementioned objectives, a field study was conducted in Tinjure Milke Jaljale (TMJ) eastern Himalaya Nepal in 2011-2013. Soil samples were collected from the depths of 0-15 cm at three soil cores in each quadrat. Quadrat size was 30*30 cm and core size was 4 cm in diameter and 15 cm deep. Composite soil sample was made while mixing all the samples of a quadrat. Five quadrats were taken from each subplot. Soil core was separated into three sections viz. 0-5, 5-10 and 10-15 cm profiles with 5 cm length of each slice. Soil sample analysis was carried out by the process of chloroform fumigation method. The Result showed that soil microbial biomass C ranged from 219. 84 to 987. 5 mg/kg. The soil microbial biomass C was increasing with decrease of grazing intensity of the rangeland and differences were significant. Similarly, the soil microbial biomass N with value of 207. 72 mg/kg was significantly higher in occasional grazing plot than two other treatments. Both soil microbial biomass C and N values were in decreasing trend with increase of soil depth of the rangeland.