Grazing Altered the Pattern of Woody Plants and Shrub Encroachment in a Temperate Savanna Ecosystem
Abstract
:1. Introduction
2. Study Area and Methods
2.1. Study Area
2.2. Data Collection
2.3. Data Analysis
2.3.1. Population Structure
2.3.2. Point Pattern Analysis
3. Results
3.1. Stand Structure
3.2. Spatial Pattern and Association of U. Pumila
3.3. Spatial Pattern of Shrubs
3.4. Spatial Association of Ulmus Pumila and Shrubs
4. Discussion
4.1. Effects of Grazing on Stand Structure
4.2. Ulmus Pumila Spatial Pattern and Influence of Grazing
4.3. Spatial Associations among Woody Species
4.4. Influence of Grazing on Shrub Encroachment
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Grazing Pressure | Plot | No. Herbaceous Species | Aboveground Herbaceous Dry Biomass/g·m−2 | Woody Species | Category | Number | Average DBH/cm | Average Height/m | Average Crown Diameter/m |
---|---|---|---|---|---|---|---|---|---|
Light | 1 | 20 | 127.63 ± 20.22 | U. pumila trees | Adult trees | 75 | 26.42 ± 4.95 | 7.54 ± 1.79 | 6.69 ± 1.41 |
Juvenile trees | 139 | 15.44 ± 4.61 | 3.78 ± 1.21 | 3.64 ± 1.09 | |||||
Seedlings | 106 | / | 0.87 ± 0.27 | 1.18 ± 0.43 | |||||
Shrubs | C. microphylla | 157 | / | 0.44 ± 0.17 | 0.63 ± 0.21 | ||||
S. aquilegifolia | 114 | / | 0.70 ± 0.24 | 0.98 ± 0.36 | |||||
S. linearitipularis | 2 | / | 1.82 ± 1.60 | 1.94 ± 1.85 | |||||
2 | 21 | 225.85 ± 13.65 | U. pumila trees | Adult trees | 83 | 24.25 ± 4.47 | 7.04 ± 1.38 | 6.17 ± 1.05 | |
Juvenile trees | 104 | 14.34 ± 3.32 | 3.96 ± 0.54 | 3.78 ± 0.76 | |||||
Seedlings | 101 | / | 0.81 ± 0.27 | 1.17 ± 0.55 | |||||
Shrubs | C. microphylla | 55 | / | 0.55 ± 0.14 | 0.68 ± 0.19 | ||||
S. aquilegifolia | 109 | / | 0.50 ± 0.16 | 0.56 ± 0.21 | |||||
S. linearitipularis | 25 | / | 1.80 ± 0.64 | 2.06 ± 0.75 | |||||
Moderate | 3 | 15 | 112.95 ± 5.09 | U. pumila trees | Adult trees | 86 | 26.81 ± 5.11 | 7.70 ± 0.97 | 7.12 ± 1.81 |
Juvenile trees | 73 | 13.98 ± 6.45 | 3.48 ± 1.83 | 3.23 ± 1.74 | |||||
Seedlings | 89 | / | 0.75 ± 0.28 | 0.92 ± 0.39 | |||||
Shrubs | C. microphylla | 24 | / | 0.79 ± 0.22 | 0.76 ± 0.21 | ||||
S. aquilegifolia | 19 | / | 0.79 ± 0.29 | 0.80 ± 0.30 | |||||
4 | 19 | 218.23 ± 12.81 | U. pumila trees | Adult trees | 78 | 28.24 ± 5.31 | 7.42 ± 0.87 | 7.61 ± 1.46 | |
Juvenile trees | 55 | 16.60 ± 5.85 | 3.22 ± 1.20 | 2.75 ± 1.29 | |||||
Seedlings | 67 | / | 0.71 ± 0.36 | 0.90 ± 0.35 | |||||
Shrubs | C. microphylla | 14 | / | 0.34 ± 0.10 | 0.70 ± 0.40 | ||||
Heavy | 5 | 14 | 80.84 ± 4.33 | U. pumila trees | Adult trees | 82 | 28.18 ± 6.18 | 7.72 ± 1.47 | 7.11 ± 2.14 |
Juvenile trees | 18 | 18.37 ± 3.72 | 4.37 ± 1.32 | 3.91 ± 0.89 | |||||
Seedlings | 6 | / | 0.92 ± 0.72 | 1.07 ± 0.91 | |||||
6 | 15 | 103.02 ± 9.65 | U. pumila trees | Adult trees | 84 | 28.57 ± 4.94 | 7.95 ± 1.35 | 7.18 ± 1.88 | |
Juvenile trees | 11 | 18.25 ± 1.23 | 4.31 ± 1.39 | 4.06 ± 1.23 | |||||
Seedlings | 9 | / | 0.94 ± 0.84 | 1.01 ± 0.87 |
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Zhang, Z.; Zhang, B.; Zhang, X.; Yang, X.; Shi, Z.; Liu, Y. Grazing Altered the Pattern of Woody Plants and Shrub Encroachment in a Temperate Savanna Ecosystem. Int. J. Environ. Res. Public Health 2019, 16, 330. https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph16030330
Zhang Z, Zhang B, Zhang X, Yang X, Shi Z, Liu Y. Grazing Altered the Pattern of Woody Plants and Shrub Encroachment in a Temperate Savanna Ecosystem. International Journal of Environmental Research and Public Health. 2019; 16(3):330. https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph16030330
Chicago/Turabian StyleZhang, Zhiyong, Bo Zhang, Xiao Zhang, Xiaohui Yang, Zhongjie Shi, and Yanshu Liu. 2019. "Grazing Altered the Pattern of Woody Plants and Shrub Encroachment in a Temperate Savanna Ecosystem" International Journal of Environmental Research and Public Health 16, no. 3: 330. https://0-doi-org.brum.beds.ac.uk/10.3390/ijerph16030330