Range Management

Vegetation changes were evaluated over a 13 year period (1988-2000) on moderately grazed and lightly grazed rangelands in the Chihuahuan Desert of south central New Mexico. During the study period, grazing use of primary forage species averaged 49 and 26% on ...

In order to study ecological and phenological traits of Prangos ferulacea as an important medicinal plant, this research was conducted in Barzok Mountains and Naragh in Esfahan province, Iran. Random samples of this plant were taken and their vegetation habitat conditions and their growth characteristics including height of collar leaves, height of the flower stem, flower stem number and forage production were recorded and categorized. Physical and chemical soil characteristics (soil texture, acidity, soil Electrical Conductivity (EC), absorbable phosphorus and potassium, and the percent of organic carbon) were examined by monthly interval at a soil depth of 30 cm from March to September. All characteristics were analyzed using factorial experiment with two factors of sites and months. Results showed that this species grow quite satisfactorily in the foothills elevation of 2750 m to 3540 m above sea level as long as it received more than 200 mm annual precipitation. The soil EC was less than 1 ds/m and acidity ranged from 7.5 to 7.8. Canopy cover in Naragh and Barzok were 15.7% and 6.1%, respectively. Results showed that growth indices as the height of collar leaves and forage production were high at the Barzok sites, while the height of flower stem was important in Naragh. For phenological process, the results indicated that plant germination started from the end of March-April and continued to the end of summer; flowering started from May-June; seeding completed in June-July and dried out completely by the end of summer. Moreover, in winter, the plants were dormant. Get the full articles at: http://www.innspub.net/volume-6-number-5-may-2015-jbes/

Assessing vegetation status via remote sensing techniques using various vegetation indices has been successfully applied to semi-arid and arid environments. We tested the feasibility of applying such techniques for assessing grazing impact in hyper-arid environments with a high variance in soil type over space. An anticlinal erosional cirque called Makhtesh Ramon in the Negev desert, Israel, was selected for the study. The cirque is typified by low rainfall (40-90 mm per year), a variety of soil substrates and is subject to grazing by a herd of ...

Some researchers have suggested that over periods of several decades, Arctic tundra caribou (Rangifer tarandus) may be regulated by density-dependent forage depletion. Winter range shifts could potentially delay such regulation when a population is at or near long-term maximum abundance. In the 1980s, Inuit correctly predicted the mass emigration of caribou from a traditional winter range on Foxe Peninsula (FP) on southern Baffin Island, Nunavut, Canada. Most FP caribou subsequently emigrated to a new winter range on Meta Incognita Peninsula (MIP). To determine if MIP provided emigrating caribou with better foraging habitats, we compared winter forage resources and snow cover at caribou foraging sites, and food selection by caribou on FP and MIP in April 1992. Caribou that remained on FP dug feeding craters in shallower, softer snow than those on MIP did. Biomass of most fruticose lichens was greater within foraging sites on MIP than on FP. Biomass of shrubs, other than Cassiope tetragona and Dryas integrifolia, was also greater on MIP than on FP. Dryas integrifolia was the only plant class that had higher biomass on FP than on MIP. Cladina spp. Cladonia spp., Sphaerophorus fragilis, and Cetraria nivalis occurred less frequently in the rumens of FP caribou. Proportions of fruticose lichens in rumens of caribou on both peninsulas were similar to those on other overgrazed and High Arctic tundra winter ranges. Caribou on FP showed a higher preference for the shrub C. tetragona. Biomasses of plants sensitive to long-term feeding or trampling by caribou (i.e., the five most common fruticose lichens, other shrubs, and plant debris) were consistently lower on FP, which is congruous with Inuit reports that long-term cumulative overgrazing had reduced the supply of important forage plants on FP sites that were accessible to caribou in winter. FP caribou that emigrated to MIP gained access to more abundant, higher quality forage resources than those that remained on FP. Because most FP caribou had emigrated, this South Baffin subpopulation escaped, at least temporarily, the regulating effects of historical cumulative overgrazing.

Rangelands are one of the most important terrestrial ecosystems that are very important in the carbon sequestration process. In this study, the amount of carbon pool was measured and compared in the habitats of Haloxylon ammodendron and Calligonum comosum in Mirjaveh plain, Sistan and Baluchestan province (in 2021). The research was based on a completely randomized design. Above and belowground biomass was harvested along 100 m transects. In order to determine the soil carbon pool of plant species, sampling was performed from three depths )0-15, 15-30 and 30-45 cm (. The amount of soil and plant organic carbon, bulk density and carbon storage of plant and soil were measured. Data were analyzed using SPPSS.20. The results showed that in both habitats, the highest and lowest amounts of organic carbon and soil carbon pool were related to depths of 0-15 and 15-30 cm, respectively. Results showed that in both habitats, soil carbon pool, bulk density, organic carbon had the maximum levels in the 0-15 cm soil layer. In C. comosum habitat, Cp in the 0-15 cm depth was more than the same soil depth in H. ammodendron habitat. In both plants, Cp in the belowground biomass was significantly more than the aboveground biomass (p<0.01). In particular, our study showed that C. comosum has more potential to store carbon compared with H. ammodendron. The use of shrubs in biological practices can increase the carbon pool in arid lands but, the efficiency of more plant species needs to be assessed.