The Effect of Grazing Intensity on Vegetation Coverage and Nitrogen Mineralization Kinetics of Steppe Rangelands of Iran (Case Study: Nodoushan Rangelands, Yazd, Iran)

Livestock grazing can affect the cycling of nutritional elements in soil by making changes to the vegetation coverage. This study aimed to investigate the effect of rangeland exploitation on vegetation coverage and nitrogen kinetics. To this end, three experimental sites of light, moderate, and heavy grazing in Nodoushan rangelands of Yazd province were selected. The vegetation properties were then measured through systematic random sampling method and three to five bases along the transect were sampled from the current year growth of the dominant plants in the region. The soil samples were collected from 0–15 cm depth in five replications and mixed together to obtain a single composite soil sample on each site. In the first stage, nitrogen (N), carbon (C), C/N, cellulose, hemicellulose, and lignin of the sampled plant as well as nitrogen, carbon, lime, soil texture, saturation moisture percentage, pH, and electrical conductivity (EC) of the soil were measured. As the soil properties did not differ for light and moderate grazing soils, different treatments were conducted on the dominant species of light and heavy grazing sites with 1% organic carbon added to the rangeland soil. Nitrogen mineralization treatments were selected based on vegetation changes that, with increasing livestock grazing intensity, changed the predominance of plant composition from Artemisia sieberi and steppe to percentage Artemisia sieberi and Peganum harmala. The treatments included control, 100% Artemisia sieberi, 75% Artemisia sieberi and 25% Peganum harmala, 50% Artemisia sieberi and 50% Peganum harmala, 25% Artemisia sieberi and 75% Peganum harmala, and 100% Peganum harmala. The soil samples were incubated for pure nitrogen mineralization in three replications of 3 months. The results of nitrogen mineralization revealed that the immobilization of the treated soil with higher Artemisia sieberi and lower Peganum harmala was done at a more rapid rate during the first week. The immobilization was slowly reduced by the third week and then followed a growing rate. Overall, the results show that an increase in grazing intensity was associated with a change in vegetation coverage toward Peganum harmala species, the biochemical characteristics of which elevated the levels of pure nitrogen mineralization in soil.

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Effects of Grazing Intensity on the Regeneration of Woody Species in an Oak Woodland

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha45210908 ◽

2017 ◽

Vol 45 (2) ◽

pp. 597-601 ◽

Cited By ~ 1

Author(s):

Aimilia LEMPESI ◽

Alexia ELEFTHERIADOU ◽

Zacharoula DELIVASI ◽

Aikaterini PSYLLIDOU ◽

Georgios KORAKIS ◽

...

Keyword(s):

Grazing Intensity ◽

Woody Species ◽

Livestock Grazing ◽

Oak Woodlands ◽

Quercus Frainetto ◽

Open Canopy ◽

Heavy Grazing ◽

Composition And Structure ◽

Mediterranean Regions ◽

Number Of Leaves

In the Mediterranean regions, oak forests are commonly used for livestock grazing. However, it is well documented that livestock grazing is an essential factor that can affect the success of natural regeneration of oak and other woody species of the understorey. Consequently, it influences the composition and structure of oak woodlands. The main objective of the present study was to examine the effects of grazing intensity on characteristics of oak seedlings establishment (density, height, number of leaves) and on the diversity of the woody species seedlings. The research was conducted in open canopy Quercus frainetto woodland, grazed by a herd of 500 goats for eight months per year, located in Evros region, north-eastern Greece. The distance from a goat corral was used to represent relative grazing intensity. In May 2016, vegetation measurements were made along transects placed at 50, 150, 300, 600 and 1200 m from the goat corral, running perpendicular to four replicates. According to the results, increased grazing intensity significantly reduced the density, the plant height and the number of leaves of Quercus frainetto seedlings. Grazing intensity did not affect significantly diversity, evenness and dominance indices for the woody species seedlings. However, heavy grazing reduced species richness and the Chao1 index.

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Grazing and Cultivated Grasslands Cause Different Spatial Redistributions of Soil Particles

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16152639 ◽

2019 ◽

Vol 16 (15) ◽

pp. 2639 ◽

Cited By ~ 1

Author(s):

Jinsheng Li ◽

Jianying Shang ◽

Ding Huang ◽

Shiming Tang ◽

Tianci Zhao ◽

...

Keyword(s):

Soil Layer ◽

Soil Health ◽

Grazing Intensity ◽

Health Condition ◽

Soil Particle ◽

Particle Sizes ◽

Soil Layers ◽

Soil Particles ◽

Heavy Grazing ◽

Grazing Intensities

The distribution of soil particle sizes is closely related to soil health condition. In this study, grasslands under different grazing intensities and different cultivation ages grasslands were selected to evaluate the dynamics of soil particle size redistribution in different soil layers. When the grazing intensity increased, the percentage of 2000~150-μm soil particles in the 0–10-cm soil layer decreased; 150~53-μm soil particles remained relatively stable among the grazing intensities—approximately 28.52%~35.39%. However, the percentage of less than 53-μm soil particles increased. In cultivated grasslands, the larger sizes (>53 μm) of soil particles increased and the smaller sizes (<53 μm) decreased significantly (p < 0.05) in the 0–10 cm-soil layer with increasing cultivation ages. The increase in small soil particles (<53 μm) in topsoil associated with grazing intensity increased the potential risk of further degradation by wind erosion. The increase in big soil particles (>53 μm) in topsoil associated with cultivation ages decreased the soil capacity of holding water and nutrient. Therefore, to maintain the sustainability of grassland uses, grazing grasslands need to avoid heavy grazing, and cultivated grasslands need to change current cultivation practices.

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Experimental evidence that livestock grazing intensity affects the activity of a generalist predator

Acta Oecologica ◽

10.1016/j.actao.2013.02.006 ◽

2013 ◽

Vol 49 ◽

pp. 12-16 ◽

Cited By ~ 9

Author(s):

Nacho Villar ◽

Xavier Lambin ◽

Darren Evans ◽

Robin Pakeman ◽

Steve Redpath

Keyword(s):

Experimental Evidence ◽

Grazing Intensity ◽

Livestock Grazing ◽

Generalist Predator

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Towards more meaningful scenarios of biodiversity responses to land-use change in Central Asia

Regional Environmental Change ◽

10.1007/s10113-020-01666-x ◽

2020 ◽

Vol 20 (3) ◽

Author(s):

Johannes Kamp ◽

Martin Freitag ◽

Norbert Hölzel

Keyword(s):

Land Use ◽

Environmental Change ◽

Central Asia ◽

Spatial Data ◽

Negative Relationship ◽

Grazing Intensity ◽

Biodiversity Loss ◽

Livestock Grazing ◽

Land Use Patterns ◽

Use Patterns

Abstract We here respond to Nunez et al. (Reg Environ Chang 20:39, 2020), recently published in Regional Environmental Change. Nunez et al. project biodiversity responses to land-use and climate change in Central Asia. Their projections are based on scenarios of changing socio-economic and environmental conditions for the years 2040, 2070, and 2100. We suggest that the predicted magnitude of biodiversity loss might be biased high, due to four shortfalls in the data used and the methods employed. These are (i) the use of an inadequate measure of “biodiversity intactness,” (ii) a failure to acknowledge for large spatial variation in land-use trends across the five considered Central Asian countries, (iii) the assumption of a strictly linear, negative relationship between livestock grazing intensity and the abundance of animals and plants, and (iv) the extrapolation of grazing-related biodiversity responses into areas of cropland. We conclude that future scenarios of biodiversity response to regional environmental change in Central Asia will benefit from using regional, not global, spatial data on livestock distribution and land-use patterns. The use of extra-regional data on the relationships between biodiversity and land-use or climate should be avoided.

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Effects of livestock grazing on soil nitrogen mineralization on Hulunber meadow steppe, China

Plant Soil and Environment ◽

10.17221/445/2015-pse ◽

2016 ◽

Vol 62 (No. 5) ◽

pp. 202-209 ◽

Cited By ~ 4

Author(s):

R. Yan ◽

G. Yang ◽

B. Chen ◽

X. Wang ◽

Y. Yan ◽

...

Keyword(s):

Nitrogen Mineralization ◽

Soil Nitrogen ◽

Livestock Grazing ◽

Meadow Steppe ◽

Soil Nitrogen Mineralization

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Effect of grazing intensity and cultivar on morphology, phenology, and nutritive value of subterranean clover II. Nutritive value during the growing season

Australian Journal of Agricultural Research ◽

10.1071/ar99092 ◽

2000 ◽

Vol 51 (8) ◽

pp. 1047 ◽

Cited By ~ 3

Author(s):

Y. J. Ru ◽

J. A. Fortune

Keyword(s):

Mineral Content ◽

Nutritive Value ◽

Grazing Intensity ◽

Subterranean Clover ◽

Growing Season ◽

Maturity Group ◽

Early Maturity ◽

Pasture Quality ◽

Heavy Grazing

With the decline in pasture quality in southern Australia, the development of management strategies to improve nutrient supply for grazing animals is essential and requires a clear understanding of the interaction between animals and plants. The impact of grazing intensity on the morphology of subterranean clover was previously examined. This paper reports the effect of grazing intensity on the nutritive value of subterranean clover, and the variation in quality of cultivars during the growing season. Grazing intensity influenced nutritive value and interacted with cultivar maturity. Heavy grazing depressed dry matter digestibility (DMD) by 5 percentage units in October for early maturity cultivars but increased DMD by 3 percentage units in September for mid maturity cultivars. The influence of grazing intensity on nitrogen content was small. Heavy grazing did not affect acid detergent fibre for the early maturity group, but depressed it for the mid maturity group throughout the season. Acid detergent lignin remained comparable for all cultivars during the season. Mineral content of subterranean clover showed variable response to grazing treatments. Nutritive value varied among cultivars within each maturity group. DMD ranged over 53–64%, 44–62%, and 45–53% for early, mid, and late maturity groups, respectively, at the end of the growing season. The cultivar rank in all nutritional parameters changed with the progress of the season. The large ranges in the decline rate of DMD within each maturity group during the last 8 weeks of growth gave an indication of the potential quality of the cultivars during late spring and early summer. Despite the variation in mineral content there were no cultivars in which the concentration of minerals was below the minimum requirements of sheep. These results indicate that there is a potential for the selection of high quality cultivars within a breeding program, and that indicative targets of grazing intensity need to be further developed with a focus on pasture quality.

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Soil hydrology and vegetation as impacted by goat grazing in Vertisols and Regosols in semi-arid shrublands of northern Mexico

The Rangeland Journal ◽

10.1071/rj17061 ◽

2017 ◽

Vol 39 (4) ◽

pp. 363 ◽

Cited By ~ 8

Author(s):

Nallely A. Carbajal-Morón ◽

Mario G. Manzano ◽

Ricardo Mata-González

Keyword(s):

Organic Matter ◽

Bulk Density ◽

Plant Cover ◽

Grazing Intensity ◽

Soil Bulk Density ◽

Soil Hydrology ◽

Goat Grazing ◽

Heavy Grazing ◽

The World ◽

Tamaulipan Thornscrub

Shrubland ecosystems are less studied than grasslands regarding the role of domestic grazing on ecosystem degradation in the world, but particularly in Mexico. Of special concern is the paucity of research on soil hydrological responses to the impact of livestock. Here, we assessed the role that specific soil and surface characteristics play in soil hydrology as a response to goat grazing intensity in two different soil types, Regosol and Vertisol, in the Tamaulipan thornscrub of north-eastern Mexico. At each soil unit, a set of grazing regimes was identified, including heavy grazing (HG), moderate grazing (MG) and a no-grazing (NG) reference area, and selected soil properties and plant cover were evaluated. In Regosol sites, soil organic matter varied among all grazing regimes (4.6% higher on NG and 2.1% higher on MG with respect HG) and no dissimilarities on bulk density were recorded. For Vertisol sites, soil bulk density increased with grazing intensity (16% higher on MG and 37% higher on HG with respect to NG) whereas plant cover linearly decreased from 86% in NG to 29% in MG and 9% in HG sites. Soil organic matter content for Regosol, and plant cover and soil bulk density for Vertisol appeared as the best indicators of water infiltration and moisture retention for the grazing conditions assessed. Differences in those key driving variables may help explain surface hydrology responses to goat grazing in rangeland soils of Tamaulipan thornscrub ecosystems and possibly on similar rangelands around the world. Clear signs of vegetation degradation were also observed, manifested by a loss in species diversity and plant cover, especially under heavy grazing. This reflects unsustainable livestock management practices that should be avoided. This study contributes to improve our understanding of rangeland degradation processes and justifies devising more sustainable grazing management schemes.

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Nitrogen mineralization in soil from perennial grassland measured through long-term laboratory incubations

The Journal of Agricultural Science ◽

10.1017/s0021859602002022 ◽

2002 ◽

Vol 138 (3) ◽

pp. 301-310 ◽

Cited By ~ 5

Author(s):

A. COLLINS ◽

D. W. ALLINSON

Keyword(s):

Organic Matter ◽

Nitrogen Mineralization ◽

N Mineralization ◽

Fertilizer Application ◽

Soil Samples ◽

N Fertilizer ◽

Mineralization Potential ◽

Perennial Grassland ◽

N Mineralization Potential

Under perennial grasslands, nitrogen contained in organic matter becomes available at varying rates via mineralization throughout the growing season. The amount of N present at any given time indicates only the quantity immediately present, and does not include N which has already been removed either by leaching or uptake into the plant system, nor the N which will become available as organic matter breaks down over time. Long-term aerobic laboratory incubation methods have been used successfully to estimate potential N mineralization under various cropping conditions. They had not been used successfully, however, to estimate potential N availability under perennial grassland.In this research, soil samples from two long-term perennial grassland sites were taken before and after N fertilizer application at rates of 0, 175, 350 and 525 kg/ha. The soils were incubated in the laboratory at 35 °C and were eluted at 2, 4, 8, 12, 16, 22 and 30-week intervals, the length of time prescribed for determining N mineralization potential. Because a plateau had not been reached, incubation was allowed to continue for 198 weeks and 148 weeks for the pre- and post-N samples, respectively. Total N was high, as was soil organic matter in both sets of soil samples. Nitrogen mineralization potential was underestimated after 30 weeks of incubation, and overestimated after 148 weeks. The closest agreement between N measured and the estimated N mineralization potential, came after 198 weeks of incubation. This study confirmed the high N-supplying capacity of soil under long-term perennial grasslands. It also indicated that the recommended 30-week period needed to estimate N mineralization potential under other cropping systems was insufficient for a perennial grassland soil. Cumulative differences in N mineralization were found with varying rates of N fertilizer application, but these differences were rarely seen on an individual weekly basis, nor were they significant at the termination of the experiment. The response to N application differed by site.

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