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Human-climate induced drivers of mountain grassland over the last 40 years in Sidama, Ethiopia: perceptions versus empirical evidence

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Ecological Processes 2018年第1期7卷 392-407页

作者： Denbeshu Debeko Ayana Angassa Aster Abebe Ashenafi Burka Adugna Tolera College of Agriculture School of Animal and Range SciencesHawassa UniversityP.O.Box 05HawassaEthiopia Wondo Genet College of Forestry and Natural Resource School of Natural Resources and Environmental StudiesHawassa UniversityHawassaEthiopia Department of Animal Science and Production Botswana University of Agriculture and Natural ResourcesPrivate Bag 0027GaboroneBotswana

Background:Mountain grasslands are globally important ecosystems.They are considered as heritage sites with“outstanding values”to ecological communities by adding a further“layer and support to the existing protection measures.”However,mountain grasslands are increasingly under threat from human activities and impacts of climate change.Methods:Using satellite imagery,we studied land use/land cover(LULC)patterns between 1973 and 2015.Individual interviews consisting of 240 households for comparison and field data collection were conducted for accuracy assessment.Results:Five categories of LULC types were identified from the image classification that included forestland,grassland,shrubland,bushland,and agricultural land.Between 1973 and 2015,the forestland,grassland,and shrubland covers were declined by 15.9%,53.6%,and 41.0%,respectively.In contrast,bushland and agricultural land were increased by 169%and 647%,respectively.The overall LULC classification accuracies for the four reference years ranged from 77.6 to 86.5%with Kappa statistic of 0.69 to 0.80.The majority of respondents(92.5%)mentioned that the cover of forestland outsized the other land use land cover types followed by grassland in the past.Conclusions:The stated indicators of land use/land cover changes linked to the impact of climate change were decline in milk yield and crop production,spread of livestock diseases,degradation of grazing lands,and change in the timing of rain.The results of the study suggest that human-climate related components were major drivers of land use/land cover dynamics that demand for proper management and conservation of mountain grassland ecosystem in Sidama South Ethiopia.

关键词： Land use/land cover Landsat Remote sensing Change detection Mountain grassland Sidama Household survey

the National Natural Science Foundation of China(41877029,41961130383);Royal SocietyNewton Advanced Fellowship(NAF\R1\191017);Wuhan Science and Technology Bureau(2019020701011469).

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Soil Ecology Letters 2022年第3期4卷 224-236页

作者： Shuzhen Li Xiongfeng Du Kai Feng Yueni Wu Qing He Zhujun Wang Yangying Liu Danrui Wang Xi Peng Zhaojing Zhang Arthur Escalas Yuanyuan Qu Ye Deng CAS Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian116024China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute for Marine Science and Technology Shandong UniversityQingdao 266237China MARBEC Universitéde MontpellierCNRSIRDIFREMERMontpellier Cedex 534090France

Due to the tremendous diversity of microbial organisms in topsoil,the estimation of saturated richness in a belowground ecosystem is still challenging.Here,we intensively surveyed the 16S rRNA gene in four 1 m2 sampling quadrats in a typical grassland,with 141 biological or technical replicates generating over 11 million sequences per quadrat.Through these massive data sets and using both non-asymptotic extrapolation and non-parametric asymptotic approaches,results revealed that roughly 15919±193,27193±1076 and 56985±2347 prokaryotic species inhabited in 1 m2 topsoil,classifying by DADA2,UPARSE(97%cutoff)and Deblur,respectively,and suggested a huge difference among these clustering tools.Nearly 500000 sequences were required to catch 50%species in 1 m2,while any estimator based on 500000 sequences would still lose about a third of total richness.Insufficient sequencing depth will greatly underestimate both observed and estimated richness.At least~911000,~3461000,and~1878000 sequences were needed for DADA2,UPARSE,and Deblur,respectively,to catch 80%species in 1 m2 topsoil,and the numbers of sequences would be nearly twice to three times on this basis to cover 90%richness.In contrast,α-diversity indexes characterized by higher order of Hill numbers,including Shannon entropy and inverse Simpson index,reached saturation with fewer than 100000 sequences,suggesting sequencing depth could be varied greatly when focusing on exploring differentα-diversity characteristics of a microbial community.Our findings were fundamental for microbial studies that provided benchmarks for the extending surveys in large scales of terrestrial ecosystems.

关键词： grassland Topsoil Prokaryote Richness α-diversity Hill number

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grassland PAINS

The World of Chinese 2016年第3期 56-57页

作者：刘莎

Homemade harvests hurt the plains冬虫夏草的'神效'背后是千疮百孔的草原Every May,people living in the Tibet Autonomous Region as well as Qinghai and southern Gansu provinces,head to the grasslands looking for'soft gold',AKA'Himalayan Viagra'—a remarkable species of parasitic fungus that specifically requires one kind caterpillar to act as host.The hunt will last until July,when the hunters are sure they’ve exhausted their quarry.

关键词： Tibet Himalayan looking fungus parasitic grassland remarkable until Plateau skill

Status and Development Strategies of grassland Agriculture: A Case Study of Dafang County

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Asian Agricultural Research 2019年第6期11卷 15-19,24页

作者： Jiahai WU Wenzhong CHEN Feng XUE Xiaodong LI Jun XIONG Fen LOU Guangji CHEN Qiong MOU Defang People s Government Dafang 551600 China Guizhou Institute of Pratacultural Guizhou Academy of Agricultural Sciences Guiyang 550006 China Bijie Animal Husbandry and Fishery Bureau Bijie 551700 China Policy Research Office Dafang Party Committee Dafang 551600 China Dafang Agriculture and Animal Husbandry Bureau Dafang 551600 China

In order to better promote the development of grassland husbandry in the Bijie experimental area and promote industrial poverty alleviation and rural revitalization strategies,the development status of grassland agriculture in developed countries( USA,Netherlands and France) and China is summarized. By learning from the successful experience of grassland agricultural development at home and abroad,combined with the survey results of grassland agriculture in Dafang County of Bijie experimental area,the development of grassland agriculture in Dafang County of Bijie experimental area is analyzed,and corresponding development strategies are put forward.

关键词： Development grassland agriculture Rural revitalization Survey Dafang Guizhou

INITIAL RESEARCH INTO CLIMATIC CHANGES AND grassland DEGENERATION IN INNER MONGOLIA

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Natural Disaster Reduction in China 2003年第4期 26-31页

作者： Li Qingfeng\+1, Li Fusheng\+2 and Wu Lan\+2 (1. College of Ecology and Environment Science, Inner Mongolia Agricultural University, Hohhot City 010019, Inner Mongolia, China 2. Xilin Gol grassland Station of Inner Mongolia, Xilin Gol, 024000, Inner Mongolia)

Based on the variation tendency of grassland productivity, this article describes the present situation of the grassland degeneration in Inner Mongolia,. With its emphasis on two main meteorological factors (precipitation and air temperature), this article analyzes the characteristics of climatic changes in the Inner Mongolia prairie in 30 years (1970～1999) and discusses the effect of climatic factors on grassland degeneration. At the same time, this article analyzes the causes for the deterioration of grassland ecological environment from such aspects as the material flow balance within the grassland ecosystem and the effect of human activities on grassland ecosystem. The analysis shows: from the present meteorological data and grassland monitoring data, it is hard to conclude that the grassland climate is getting drier and drier and proceeds to cause the deterioration of the grassland ecosystem; animal husbandry is the main type of land use in this area, the vegetations within the ecosystem are mainly controlled by domestic animals, and the main causes for the rapid deterioration of grassland ecosystem are the malajustment of input and output of material flow (take N for example) and the seasonal imbalance of supply and demand between the grass and the domestic animals; while the climatic changes only make the deterioration of the ecosystem more serious. This article proposes that the effective measures to harness and maintain the grassland ecosystem health in this area are to increase the material input within the ecosystem, to adjust the nature production mode of grazing all through the four seasons, and to actively introduce new seeds into animal husbandry to alleviate the grazing pressure on the grassland during the sensitive spring period, etc..

关键词： Inner Mongolia prairie grassland ecosystem climatic changes grassland degeneration

Developing the Agro-grassland System to Insure Food Security of China

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Journal of Agricultural Chemistry and Environment 2014年第3期3卷 9-15页

作者： Ruichao Li Huilong Lin State Key Laboratory of grassland Agro-Ecosystems College of Pastoral Agriculture Science and Technology Lanzhou University Lanzhou China

China’s food security has always been the top priority in China. As the huge increase of animal food consumption, the current agriculture system in China namely “grain farming”, whose major animal feed are grains, seems to meet a great challenge to ensure China’s food security in the future. Not only the current situation, but also the production capacity as developing grassland agriculture is analyzed in this paper. The results show that half of provinces don’t have enough grain to meet their various needs for grain, and the whole country’s potential of grain yield is reaching a limited position. On the other hand, implementing cereal-forage rotation on 20% of the total arable land and developing high productivity sown pastures on 3% of the total rangeland areas could create approximately 1.2 times Arable Land Equivalent Unit (ALEU) than ever. So changing the traditional agriculture system into grassland Agro-Ecosystems is an effective way to insure China’s food security. It includes utilization of rangeland rationally, establishment of more sown pasture and implementation of cereal-pasture rotation system, increase livestock production, and use of arable land more efficiently.

关键词： Food Security grassland Agriculture Arable Land Equivalent Unit China

Experimental study on soil CO_2 emission in the alpine grassland ecosystem on Tibetan Plateau

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Science China Earth Sciences 2005年第Z1期48卷 218-224页

作者： ZHANG Xianzhou SHI Peili LIU Yunfen OUYANG Hua Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The Tibetan Plateau, the Roof of the World, is the highest plateau with a mean elevation of 4000 m. It is characterized by high levels of solar radiation, low air temperature and low air pressure compared to other regions around the world. The alpine grassland, a typical ecosystem in the Tibetan Plateau, is distributed across regions over the elevation of 4500 m. Few studies for carbon flux in alpine grassland on the Tibetan Plateau were conducted due to rigorous natural conditions. A study of soil respiration under alpine grassland ecosystem on the Tibetan Plateau from October 1999 to October 2001 was conducted at Pangkog County, Tibetan Plateau (31.23°N, 90.01°E, elevation 4800 m). The measurements were taken using a static closed chamber technique, usually every two weeks during the summer and at other times at monthly intervals. The obvious diurnal variation of CO2 emissions from soil with higher emission during daytime and lower emission during nighttime was discovered. Diurnal CO2 flux fluctuated from minimum at 05:00 to maximum at 14:00 in local time. Seasonal CO2 fluxes increased in summer and decreased in winter, representing a great variation of seasonal soil respiration. The mean soil CO2 fluxes in the alpine grassland ecosystem were 21.39 mgCO2 · m-2 · h-1, with an average annual amount of soil respiration of 187.46 gCO2 · m-2 · a-1. Net ecosystem productivity is also estimated, which indicated that the alpine grassland ecosystem is a carbon sink.

关键词： soil CO2 emission, alpine grassland ecosystem, Tibetan Plateau.

Calibrating Vegetation Cover and grassland Pollen Assemblages in the Flint Hills of Kansas, USA

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American Journal of Plant Sciences 2013年第7期4卷 1-10页

作者： Julie L. Commerford Kendra K. McLauchlan Shinya Sugita Department of Geography Kansas State University Manhattan USA Department of Geography Kansas State University Manhattan USA Institute of Ecology Tallinn University Tallinn Estonia.

grassland cover and composition respond to climate and have undoubtedly changed during the Holocene, but quantitative reconstructions from fossil pollen have been vague about spatial scale and taxon-specific cover. Here, we estimate the relevant source area of pollen for sedimentary basins approximately 50 m in radius, and we report pollen productivity estimates for 12 plant taxa in the tallgrass prairies of central North America. Both relevant source area of pollen and pollen productivity estimates were calculated via the Extended R-Value Model. To obtain these estimates, we collected and quantified the pollen found in surface sediment samples from 24 ponds across the study area. Vegetation was surveyed in the field in a 100 m radius around each pond, and vegetation maps from the Kansas Gap Analysis Project (GAP) were used to a radius of 2 km. Pollen fall speeds were calculated according to Stoke’s Law. Pollen assemblages from basins approximately 50 m in radius have a relevant source area of 1060 m in this grassland landscape. Pollen productivity estimates range from 0.02 to over 30 among the 12 taxa: Artemisia, Ambrosia, Asteraceae, Chenopodiaceae, Cornus, Fabaceae, Juniperus, Maclura, Poaceae, Populus, Quercus, and Salix. Woody taxa generally have higher pollen productivity than herbaceous taxa (except for Chenopodiaceae and Ambrosia).

关键词： grassland Pollen Prairie North America Paleoecology

What determine herder households' sustainable grassland management behaviors in western China?

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Ecological Economy 2014年第2期7卷 108-119页

作者： TAN Shu-hao TAN Zhong-chun School of Agricultural Economics and Rural Development Renmin University of China School of Management Science & Industrial Engineering Nanjing University of Finance & Economics

grassland is most important in China due to its multi-functions. However, about 90% of total usable grassland in China has been degraded and the degradation expands at a rate of 2 million ha per year. Western China covers 6.12 million square kilometers and 63.8% of the total national area with a distribution of 50 minority nationalities and 75% of the minority national population. Ecological environment there is very vulnerable with more than 90% areas of the annually increased degradation taking place. Under the current tenure arrangement, the individual herder households become the main and direct users of grassland, their decision-making on grassland management may have crucial impact on ecological environment as well as their livelihoods. Thus, it is necessary to examine the determinants of their grassland management behaviors. This study applies 231 household field data from 6 provinces of western China and uses econometric models to explore the major constraints for restricting the herd households' grassland management behaviors. Main results show that under the current tenure and other governance measures, institutional factors, market price and herder's farm and household's characteristics affect the grassland management behaviors.

关键词： grassland herd household model institutions land g