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Journal of Forestry Research 2024年第1期35卷 168-182页

作者： Alessandra Pacini Francesco Pelleri Francesco Marini Alberto Maltoni Barbara Mariotti Gianluigi Mazza Maria Chiara Manetti Department of Agriculture FoodEnvironmentand ForestryUniversity of Florence50144 FlorenceItaly CREA Research Centre for Forestry and Wood 52100 ArezzoItaly PEFC Programme for the Endorsement of Forest Certification 06135 PerugiaItaly

On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in four types of grazed areas based on the grazing regime adopted:calf-grazed,high-intensity-grazed,low-intensity-grazed,ungrazed control.For each area,we set up three permanent circular plots(radius of 15 m)to survey the structural and dasometric characteristics of the overstorey,understorey,and regeneration layer.The results showed that grazing negatively affected the complexity of the forest structure and its potential to regenerate and maintain a high level of biodiversity.The differences in stand structure observed between the grazing areas were closely related to livestock density.The most sensitive components of the system were the understorey and the regeneration layers.Contrarily,the current grazing management did not affect the dominant tree structure or its composition.Our findings identified medium-term monitoring and regeneration management as the two significant aspects to consider when assessing sustainable livestock.New forests can be established by excluding graz-ing for about 20–25 years.

关键词： Agroforestry Stand structure Regeneration Tree biodiversity grazing intensity

grazing intensity affects vegetation characteristic and soil property of alpine meadows in the eastern part of Qinghai-Tibetan plateau

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Grazing intensity affects vegetation characteristic and soil...

Effect of grazing intensity on photosynthesis and soil respiration of alpine grassland in Tibet

中国—澳大利亚可持续性草地管理研讨会

作者： Ji Lei,Gan You-Min~*,Luo Yuan-Jia Department of Grassland Science,Animal Science and Technological College,Sichuan Agricultural University,Ya’an,625014 Sichuan Province,PRC.

Introduction:The study was to determine the impact of grazing intensity on vegetation and soil of alpine meadows to detect the species distribution in vegetation composition along different grazing intensity gradients. Material and Methods:A study mainly located in Hongyuan in the southeastern part of the Qinghai-Tibetan plateau(QTP),which covers over 2.5 million km,is the focus of ecosystem

关键词： grazing intensity Vegetation characteristics Soil properties Classification Ordination

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Effect of grazing intensity on photosynthesis and soil respi...

Morphological and productivity responses of Buffel grass(Cenchrus ciliaris)and Guinea grass(Panicum maximum)ecotypes to simulated grazing in a semi-arid environment

ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： Y.F.Wan~1,Q.Z.Gao~1,Y.Li~1,X.B.Qin~1,W.Z.Jiancun~2,B.S.Wang~3 1 Institute of Environment and Sustainable Develop in Agriculuture,Chinese Academy of Agricultural Sciences,Haidian, Beijing,100081,China.2 Administrator office of Naqu,Tibet,China,852000 3 Grassland Station of Naqu,Tibet,China,852000

Introduction Naqu locates at the northern Tibet,and also the higher part of Tibet.Alpine grassland is one of the dominant grassland systems at Tibet Plateau.But how the effect of grazing on its photosynthesis and soil respiration is still not very clear.To understand the relationship between them will help to evaluate the sustainable development of grazing capacity and CO emission from this system.

关键词： alpine grassland Northern Tibet grazing intensity photosynthesis soil respiration

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Grassland Research 2022年第4期1卷 290-300页

作者： Bosco Kidake Kisambo Oliver V.Wasonga Oscar K.Koech George N.Karuku Department of Land Resources Management and Agricultural Technology University of NairobiNairobiKenya Arid and Range Lands Research Institute—Kiboko Kenya Agricultural and Livestock Research Organization(KALRO)NairobiKenya

Background Livestock production is an economically significant activity in grassland-based production systems with herbivory,a critical process in modifying plant structure and regulating biomass dynamics in these areas.Methods A grazing simulation experiment was undertaken in a semi-arid environment in Kenya to determine the effects of clipping frequency and intensity on the morphology and productivity of Cenchrus ciliaris and Panicum maximum grass ecotypes.The ecotypes were clipped at different frequencies(every 2,4,and 12 weeks)and different intensities(5,10,and 15 cm clipping heights).The morphological responses of the grass ecotypes and biomass yields were determined.Results The grass ecotypes showed significantly(pintensity.Morphological parameters,tillering,and biomass production were all affected by clipping frequency and intensity.The highest dry matter(DM)yields were recorded under low frequency(LF)clipping,followed by moderate frequency(MF)clipping and high frequency(HF)clipping.LF clipping in C.ciliaris ecotype Kilifi was 20%and 31%more compared to MF and HF clipping.No significant difference in yields was found by cutting the C.ciliaris ecotype Magadi at 4-and 12-week intervals,even though clipping at 2-week intervals cumulatively yielded less biomass.There was a biomass yield reduction in P.maximum ecotype Taveta of 23%and 25%for MF and HF clipping,respectively,while for ecotype Isinya,the reduction was 13%and 15%for MF and HF,respectively.Clipping intensity had a significant(pgrazing and cutting strategies are advantageous for semi-arid lands.Combinations of frequent and high-intensity u

关键词： dry matter dryland grasslands grazing grazing frequency grazing intensity pastures rehabilitation

Ammonia emissions from soil under sheep grazing in Inner Mongolian grasslands of China

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Journal of Arid Land 2013年第2期5卷 155-165页

作者： YunHai ZHANG NianPeng HE GuangMing ZHANG JianHui HUANG QiBing WANG QingMin PAN XingGuo HAN State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Synthesis Research Center of Chinese Ecosystem Research Network Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences

Ammonia （NH3） emission and redeposition play a major role in terrestrial nitrogen （N） cycles and can also cause environmental problems, such as changes in biodiversity, soil acidity, and eutrophication. Previous field grazing experiments showed inconsistent （positive, neutral, and negative） NH3 volatilization from soils in response to varying grazing intensities. However, it remains unclear whether, or to what extent, NH3 emissions from soil are affected by increasing grazing intensities in Inner Mongolian grasslands. Using a 5-year grazing experiment, we investigated the relationship between NH3 volatilization from soil and grazing pressure （0.0, 3.0, 6.0, and 9.0 sheep/hm2） from June to September of 2009 and 2010 via the vented-chamber method. The results show that soil NH3 volatilization was not significantly different at different grazing intensities in 2009, although it was higher at the highest stocking rate during 2010. There was no significant linear relationship between soil NH3 volatilization rates and soil NH4^-N, but soil NH3 volatilization rates were significantly related to soil water content and air temperature. grazing intensities had no significant influence on soil NH3 volatilization. Soil NH3 emissions from June to Sep- tember （grazing period）, averaged over all grazing intensities, were 9.6±0.2 and 19.0±0.2 kg N/hm2 in 2009 and 2010, respectively. Moreover, linear equations describing monthly air temperature and precipitation showed a good fit to changes in soil NH3 emissions （r=0.506, P=0.014）. Overall, grazing intensities had less influence than that of climatic factors on soil NH3 emissions. Our findings provide new insights into the effects of grazing on NH3 volatili- zation from soil in Inner Mongolian grasslands, and have important implications for understanding N cycles in grassland ecosystems and for estimating soil NH3 emissions on a regional scale.

关键词： NH3 N emission grazing intensity stocking rate nitrogen cycle Inner Mongolia

理解青藏高原三江源地区放牧压力的空间异质性

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Journal of Geographical Sciences 2023年第8期33卷 1660-1680页

作者：谷昌军刘林山张镱锂魏博崔伯豪宫殿清 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China National Disaster Reduction Center of China Ministry of Emergency ManagementBeijing 100124China

Elucidating the distribution of the grazing pressure requires an understanding of the grazing activities.In this study,we analyzed the grazing behavior of yaks in Three-RiverSource Region(TRSR)and identified the main factors influencing the distribution of grazing intensity(GI)using trajectory data and remote sensing datasets.Our results revealed that a semi-resident transhumance strategy is employed in this region.The average grazing time(GT)of four GPS collars over the year was 11.84 h/day(N6),11.01 h/day(N11),9.25 h/day(N18),and 11.61 h/day(N24).GT was generally higher in warm seasons(summer and autumn)than in cold seasons(spring and winter).The average daily moving speed was found to be closely related to the pasture size of different herders and the seasons.Geodetector analysis identified the distance to camp(DOC)as the most important single factor influencing the distribution of GI,explaining up to 52% of the GI variations.However,relying solely on this factor may not accurately depict the actual GI distribution.When pairwise factors interacted,the explanatory power of the model increased,ranging from 34.55% to 63.26%.Our study highlights the importance of considering multiple factors when predicting grazing intensity,as grazing activities tend to cluster near settlements,but other factors may also be influential.

关键词： grazing intensity GPS-tracking spatial heterogeneity yak Tibetan Plateau

Satellite remote sensing of grasslands:from observation to management

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Journal of Plant Ecology 2016年第6期9卷 649-671页

作者： Iftikhar Ali Fiona Cawkwell Edward Dwyer Brian Barrett Stuart Green Department of Geography University College CorkCorkIreland Spatial Analysis Unit TeagascDublinIreland EurOcean-European Centre for Information on Marine Science and Technology LisbonPortugal School of Geographical and Earth Sciences University of GlasgowGlasgowUK

Aims Grasslands are the world’s most extensive terrestrial ecosystem,and are a major feed source for livestock.Meeting increasing demand for meat and other dairy products in a sustainable manner is a big challenge.At a field scale,Global Positioning System and ground-based sensor technologies provide promising tools for grassland and herd management with high precision.With the growth in availability of spaceborne remote sensing data,it is therefore important to revisit the relevant methods and applications that can exploit this imagery.In this article,we have reviewed the(i)current status of grassland monitoring/observation methods and applications based on satellite remote sensing data,(ii)the technological and methodological developments to retrieve different grassland biophysical parameters and management characteristics(i.***.degradation,grazing intensity)and(iii)identified the key remaining challenges and some new upcoming trends for future development.Important Findings The retrieval of grassland biophysical parameters have evolved in recent years from classical regression analysis to more complex,efficient and robust modeling approaches,driven by satellite data,and are likely to continue to be the most robust method for deriving grassland information,however these require more high quality calibration and validation data.We found that the hypertemporal satellite data are widely used for time series generation,and particularly to overcome cloud contamination issues,but the current low spatial resolution of these instruments precludes their use for field-scale application in many countries.This trend may change with the current rise in launch of satellite constellations,such as RapidEye,Sentinel-2 and even the microsatellites such as those operated by Skybox Imaging.Microwave imagery has not been widely used for grassland applications,and a better understanding of the backscatter behaviour from different phenological stages is needed for more reliable products in cloudy regions.The development of hyperspectra

关键词： remote sensing agricultural grassland grassland biomass pasture management grazing intensity

Analysis of Grassland Vegetation of the Southwest Heilongjiang Steppe （China） Using the Power Law

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Journal of Integrative Plant Biology 2005年第8期47卷 917-926页

作者： Mikinori TSUIKI Yu-Sheng WANG Yiruhan Michio TSUTSUMI Masae SHIYOMI Faculty of Agriculture lwate University Morioka 020-8550 Japan National Northeast Agricultural University Harbin 150030 China Environmental Engineering Department College of Science and Engineering Jinan University Guangzhou 510630 China National Institute of Livestock and Grassland Science Ecology Department Tochigi 329-2724 Japan Faculty of Science lbaraki University Mito 310-8512 Japan

In 1997, we conducted a vegetation survey in three semi-arid natural grasslands （steppes） with different livestock grazing intensities in Southwest Heilongjiang Province, China, The dominant grassland species was the grass Stipa baicalensis Roshev. Grasslands with light, intermediate, and heavy grazing intensities were located 10, 5, and 2 km from a village, respectively. Villagers use the steppe to raise cattle, horses, sheep, and goats. Each of the three grasslands was surveyed by placing 100 quadrats （50 cm×50 cm） along a 50 m line transect. Each quadrat was divided into four equal areas （25 cm×25 cm; S-quadrats） and all plant species occurring in each of these smaller areas were identified and recorded. These data were summarized into frequency distributions and the percentage of S-quadrats containing a given species and the variance of each species were estimated. The power law was applied to these estimates. The power law was used to evaluate the spatial heterogeneity and frequency of occurrence for each species in the grassland community. The lightly grazed grassland exhibited high spatial heterogeneity （caused by large plant size）, the highest species diversity, and a high occurrence of S. baicalensis. In contrast, the heavily grazed grassland exhibited high spatial heterogeneity （caused by patchy populations of small plant size）, low species diversity, and a low occurrence of S. baicalensis. We judged that the heavily grazed grassland was overgrazed and exclusion of livestock from the degraded areas is necessary for recovery.

关键词： degradation grazing intensity Heilongjiang （China） spatial heterogeneity species diversity steppe Stipa baicalensis.

Environmental filtering does not necessarily prevent trait divergence: a case study of the Xilin River Basin in Inner Mongolia, China

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Journal of Plant Ecology 2017年第3期10卷 497-509页

作者： Saruul Kang Jianming Niu Qing Zhang Dan Li Haijuan Ren Jing Ren Xuefeng Zhang Jianjun Dong School of Life Sciences Inner Mongolia University235 University West RoadHohhot 010021China Sino-US Center for Conservation Energyand Sustainability ScienceInner Mongolia University235 University West RoadHohhot 010021China

Aims Understanding how environmental factors and human activity drive plant community assembly remains a major challenge in community ecology.Two opposing processes,namely determinis-tic environmental filtering and nondeterministic elements such as interspecies competition,can be quantified by analyzing trait distri-butions in the community-assembly process.Methods We examined the trait-mediated effects of environmental filtering and stochastic process and the distribution over time of nine traits related to vegetative growth,regenerative phase,dispersal capability,decom-position and interspecific competition in plant communities along a degradation gradient in the Xilin River Basin,Inner Mongolia,China.We analyzed the turnover of environmental trait filtering and the diver-gence/convergence of different traits along the degradation gradient.Important Findings Our results showed the following.(i)The patterns of trait distribu-tion and filtering were strongly dependent upon the degradation gradient and trait types.Most traits were filtered intensely in degraded grasslands.(ii)Plants with two different strategies showed contrasting trait-distribution patterns.The traits that were related to biological matter cycling showed divergent pat-terns in highly degraded grasslands,while convergent patterns along the overall gradient were demonstrated in traits associated with other plant strategies.This suggests that the coexistence of multiple‘biological matter cycling-related niches’might be a basic structuring pattern of plant communities in our study area.(iii)The simultaneous occurrence of strong filtering and diver-gence revealed that environmental filtering does not necessar-ily prevent competition,and that different traits show different signatures.

关键词： community assembly convergence degradation grazing intensity plant traits typical grassland

Effects of grazing and climate change on sandy grassland ecosystems in Inner Mongolia

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Research in Cold and Arid Regions 2011年第3期3卷 223-232页

作者： HaLin Zhao Toshiya Okuro RuiLian Zhou YuLin Li XiaoAn Zuo Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou Gansu 730000 China Graduate School of Agricultural and Sciences University of Tokyo Tokyo 1138657 Japan Faculty of Life Sciences Ludong University Yantai Shandong 264025 China

To understand the effects of grazing activities and climate change on sandy grassland ecosystems in northem China, a livestock field grazing and enclosure experiment was conducted from 1992 to 2006 in Horqin Sand Land, Inner Mongolia. The results showed that sustained heavy grazing resulted in serious degradation of the vegetation; moderate grazing can maintain vegetation stabilization; and light grazing can promote rapid restoration of degraded vegetation. The livestock productivity was the highest in the moderate grazing grassland, and sustained heavy grazing resulted in rapid decrease of the livestock productivity. Heavy grazing can cause a retrogressive succession of grassland vegetation, whereas moderate and light grazing may promote progressive succession of plant species. The effects of changing climate on succession processes were not significant in the short term; a warm-humid climate is favorable to restoration of degraded vegetation, whereas a sustained warm-drought climate may result in degradation of grassland vegetation. Heavy livestock grazing should be stopped for the sustainable use of grassland; the proper grazing intensity for sandy grassland is two to three sheep or sheep equivalents per hectare in Inner Mongolia.

关键词： grazing intensity climate change sandy grassland ecosystem dynamics Inner Mongolia