JOURNAL OF RANGELAND SCIENCE
Year:2019 | Volume:9 | Issue:3 |Papers Count:9

Undoubtedly, land degradation linked to desertification causes a decrease in qualitative and quantitative features of natural resources. This research aimed to assess land desertification by local residents and their role in controlling desertification in Isfahan province, Iran in 2016. The criteria were soil climate, vegetation, erosion, and demography. The indicators of soil texture, stone fragment, organic matter, soil depth, Electrical Conductivity (EC), soil drainage, soil slope, precipitation, evapotranspiration, aridity index, fire risk, erosion protection, drought resistance, plant cover percent, wind erosion, water erosion, land use, population density, grazing intensity, policy, and management. Some parameters include land use, DEM, NDVI, roads, springs, fire history data, stress intensity, tolerance, mean productivity, AUM index, lithology, morphology and relief, wind speed, soil characteristics, plant cover percent, wind erosion features, soil moisture, type and distribution of sand dunes, and land management. The assessment of desertification has been conducted by the Mediterranean Desertification and Land Use (MEDALUS) method in ArcGIS10 software. This research was based on the importance of socio-economic issues, establishing a realistic framework for qualitative indicators and indices adapted to Iran’ s situation. Those are population, poverty and economics, people rights and institutional regulations, and sociocultural criteria achieved by an interview with local communities and experts. A single desertification status map was generated based on all the quality maps. Finally, the generated map was compared with local settlements density map. Results showed that 91. 23% of the rangelands (with area 38203 km2) are classified as severe and moderate with low settlements density and 1. 83% of the rangelands (with area 766 km2) are lower in severity with high settlement density. This result illustrated that local settlements and nomadic have a positive role in combating the desertification. They are able to eliminate the desertification to minimum and vice versa. The desertification status and local settlements density maps are essential in management efforts to combat the desertification via local settlement abilities.

In applied studies, the investigation of the relationship between a plant species and environmental variables is essential to manage ecological problems and rangeland ecosystems. This research was conducted in summer 2016. The aim of this study was to compare the predictive power of a number of Species Distribution Models (SDMs) and to evaluate the importance of a range of environmental variables as predictors in the context of rangeland vegetation. In this study, Aflah rangelands with 5721 ha were selected. In this research, predictor variables included climatic, topographic and edaphic parameters. The sampling method was equal random-classification for vegetation and soil. Topographic factors including slope, elevation and aspect were determined in Arc GIS software. In each sample unit, 10 plots were established (total 350 plots) and the lists of the species, their number, their presence or absence were recorded. The efficacy of five different modelling techniques to predict the distribution of five dominant rangeland plant species (Agropyron repens, Festuca ovina, Leucopoa sclerophylla, Stachys lavandulifolia and Tragopogon graminifolius) was evaluated. The models were Generalized Linear Model (GLM), Classification and Regression Trees (CART), Boosted Regression Trees (BRT), Generalized Additive Models (GAM), and Random Forest (RF). Data analysis was done using the R software, version 3. 1. 1. The results showed that GAM model demonstrated most consistently high predictive power over the species in the rangeland context investigated here. GAM had higher Area Under the Curve (AUC). The AUC (0. 67, 0. 77, 0. 69, 0. 64 and 0. 60 and Kappa values (0. 10, 0. 10, 0. 19, 0. 01 and 0. 11) were obtained for Agropyron repens, Festuca ovina, Leucopoa sclerophylla, Stachys lavandulifolia and Tragopogon graminifolius, respectively. GAM model exhibited the most predictive power. The importance analysis of the environmental variables showed that N, pH and aspect were the most important variables in the GAM model. Overall, N, P and C/N soil (0. 452, 0. 437 and 0. 389) were the most important environmental variables.

Forage is one of the main products of rangeland ecosystems, which is threatened by different anthropogenic disturbances. This study was conducted to assess the impact of urbanization, rural development, agriculture extension, road construction and industry on forage production in an arid and semiarid rangeland using InVEST habitat quality model in spring 2018. In 14 rangeland types, thirty 2×1m quadrats were randomly located to measure forage production using double sampling method. Habitat quality was mapped based on the relative impact of each threat, the relative sensitivity of each rangeland type to each threat and the distance between the habitats and threats. The results showed that there is a significant relationship between rangeland condition and habitat quality (p<0. 01). Habitat quality varied between 0 and 0. 77 across the study region. Habitats with low quality comprised half of the total area (51%) where anthropogenic factors were concentrated. Habitat quality was significantly correlated with forage production (p<0. 01). The dominant species Artemisia sieberi was replaced by invasive species Salsola brachiata and forage production was decreased to the minimum 21 kg ha-1 in habitats with low quality. Rangelands with medium habitat quality produced two and a half times more forage than the ones with low habitat quality and half of the ones with high habitat quality. Astragalus gossypinus and Artemisia aucheri in high habitat quality areas supplied the highest forage production (216 kg ha-1). Since the large areas of agricultural lands are in the low quality habitats, agriculture can be considered as the main threat of forage production. Hence, the extension of agricultural lands with short-term benefits should be controlled in order to improve ecosystem services which have long-term benefits in sustainable development.

Adaptation of plants under drought and salinity stress depends directly on the type of soil texture. Therefore, in this research, the morpho-physiological variations of Stachys multicaulis, an Iranian wild endemic plant species, were investigated in different soil textures under drought and salinity stress. For this purpose, plants were cultivated in three different light, medium and heavy soil textures under pot condition (outside the greenhouse near the plant original habitat) in 2016. Then, a set of drought stress (3 day intervals of irrigation; 3 to 15 days) and salinity stress (0, 5, 10, 15, 20 and 25 ds/m-NaCl) was used in two separate factorial experiments based on a completely randomized design with four replications. The results showed that both drought and salinity had significant effects on morpho-physiological properties of S. multicaulis (p<0. 01) based on type of soil texture. All of traits had higher performance in heavy soil texture except trichome length. For 15 day interval of irrigation, higher values of plant biomass, plant greenness, leaf length/width ratio, leaf angle, and node distance as 8. 25g, 28. 1%, 4. 17, 55° , 1. 5cm respectively were obtained in heavy soil texture. Similarly, for salinity of 25 ds/m, higher values of same traits as 7. 7g, 25%, 3. 9, 50° , and 1. 4cm, respectively were obtained in heavy soil texture. Both drought and salinity stress had no significant effect (p<0. 01) on leaves trichome number, trichome length, floret number per plant and branch number per plant in all three soil textures. The morphological variations of the plant occurred with greater intensity in salinity stress and it was concluded that plant tolerance to salinity was lower than drought.

This study was carried out in Bale Eco-Region (BER) which is located in Southeastern Ethiopia with the objective of addressing the cause and effect of ecological damage, particularly rangeland degradation. Both purposive and stratified random sampling approaches were used to select HouseHolds (HH). Individual interview, key informants and Focus Group Discussion (FGD) were the main sources of data for this study. The livelihood activity in BER lowland area was pastoralism before 1965 and it was based on highly productive, vast and free Rangeland with unlimited movement of the pastoralists. In the low land of BER, migration has a destination, pattern and objective to meet. These destinations are sources of mineral, a breeding site, feed and water. Migration is used as strong seasonal disease, water and feed shortage escaping mechanism. However, this is currently changed to Agro-pastoral or some of them to crop production do different disturbances. The change was mainly aggravated by expansion of agricultural investment, high population growth, illegal settlement and cultivation and banning of migration to Forest. Utilization of grazing land is communal and rangeland around homestead and watering points are overgrazed and resulted in bare land and encroached by unpalatable and thorny species. The vegetation cleaning and cultivation of drought prone area under rain-fed regimes have accelerated bare land expansion and unpalatable vegetation encroachment. The overall rangeland condition has deteriorated and the livelihoods were jeopardized. The people get in trouble, then moving from degraded area to protected and moist source forest land in Bale Mountain National Park and now causing serious deforestation.

One of the most important issues in rangeland management is the estimation of carrying capacity. To estimate range production, we need to use a large number of sample plots to clip plants in a sampling scheme; therefore, due to vast area of rangelands and time and cost limitations, direct estimation of rangeland production by sampling plots is almost impossible. Since there is a strong relationship between climatic factors and rangeland production, using indirect estimation methods of rangeland production is important. The relationship between production samples and climatic factors can be easily predicted. Present study was conducted in five locations of Spandol, Zarchak, Torogh, Aselme, and Dash, Iran in 2013. In this research, the relationships between forage production and three climate parameters including precipitation, temperature, and precipitation to temperature ratio (P/T) were investigated. For each parameter, 33 variables (periods) were considered. Stepwise regression analysis was used to select the most effective periods of precipitation and temperature. The relationship between production and March to April precipitation and November to December temperature was positive but with October to March temperature, it was negative. The relationship between production and P/T was negative in May to June and positive in January to March. In general, simultaneous of rainfall and temperature had effective roles in increasing dry matter production of grasslands in the studied areas.

Dust events of Iran mainly originate from Iraq, Syria, Saudi Arabia, Kuwait and inland territories which are influenced by droughts and Land Use/Land Cover (LU/LC) degradation in regional scale. The aim of this research was to investigate the impact of Regional Vegetation Cover Degradation (RVCD), particularly Regional Rangeland Cover Degradation (RRCD) on frequency of dusty days in western provinces of Iran (Khorramabad, Ahvaz, Hamadan and Kermanshah) since 2000. Therefore, the LU/LC and RRCD were evaluated with respect to time-series MODIS satellite images and NDVI Index. The trend of RRCD was predicted by Markov chain analysis for 2030, 2060 and 2100. The accuracy analysis of comparing the observed and predicted LU/LC classes to 2000 and 2016 indicated the absolute value of error around 5. 49%. The findings showed that probability of changing from water body, high-cover and low-cover classes to noncover class would probably be 55% and 62% during 2016-2030 and 2030-2060, respectively. Durability of non-cover class was 89% during 2000-2016. Thus, the area of non-cover class increased to 410 km2 in the study region. In general, it could be noted that increasing of RRCD and drought are the main causes of dusty days increasing from 2000 to 2060.

The watershed (DAS) Deli is one of the priority watersheds in the Medium Term Development Plan in 2010-2014 according to the Ministry of Forestry decree (SK 328/Menhut-II/2009), Indonesia. DAS is a complex ecological system in which there is a dynamic equilibrium between the incoming material energy (input) and the material out (output). Naturally, the change in input and output balance is slow and does not pose a threat to humans and environmental sustainability on a watershed system with continuous land-use dynamics from dense vegetation forms to rare vegetation forms or from vegetation forms to non-vegetation forms. It has been concluded that Deli watershed land destruction is dominated by biophysical factors, especially land use, slope, landform, and rainfall in upstream Deli sub-watershed. This is what causes flooding in Medan city, Indonesia. The cause is extreme rainfall so that a number of rivers such as Deli River and Babura River overflowed, the water level of the Deli and Babura Rivers almost reached the bridge section and this was scarce.

A region is considered self-sustainable when the feed provision is adequate for all livestock demands. Livestock is fed in order to supply nutrient needs for maintenance, growth, and reproduction purposes. This study aimed to determine whether Madura Island in Indonesia is able to independently provide sufficient forage for its ruminant livestock. A Carrying Capacity Index (CCI) in four regions of Madura Island was determined and then, the capacity to sustain additional ruminant livestock was calculated. The results showed that Sumenep and Pamekasan with average values of 454306 and 90663 BKC had the highest and lowest potentials for the supply of fresh forage, respectively. Sumenep also had the best carrying capacity of all the analyzed regions, supporting up to 231879 ST ruminants. Also, the results suggest that Madura Island was already at overcapacity with the livestock population that exceeds the region’ s capability to provide feed from fresh or waste agricultural products.