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| 1 | Sustainable management of Chinese grasslands—issues and knowledge显示文摘China has almost 400 Mhm^2 of grasslands,90% of which is considered degraded to varying degrees,on which 16 million herders depend for their livelihoods and many more indirectly, along the value-adding chain.Since 1950, average stocking rates across China have increased 4-fold. National policies have focused over recent decades on finding ways to rehabilitate the degraded grasslands, to sustain livestock production from them, and to improve the livelihoods of herder households, who are among the poorest people in China. A large collaborative program commenced in the early 2000 s to help find solutions to the sustainable management of grasslands.This paper summarizes key findings of many research projects, identifies where knowledge is weak and argues that the successful rehabilitation of grasslands will also require policies that provide incentives and support for herders as they move from a focus on survival to a focus on production of higher quality products, for which consumers are increasingly willing to pay. A key focus is to emphasize the improvement of animal production per head. When this is done, it naturally leads to lower stocking rates, which in turn provides the opportunities for grasslands to recover. Across a range of experiments, farm demonstrations and analyses using models, in Inner Mongolia and Gansu, a consistent result has been that a 50% reduction in stocking rates, improves net household income and starts the process of grassland rehabilitation.Rather than focusing on stocking rates, better management of grasslands could be achieved by maintaining the grasslands above critical values for herbage mass, values that help optimize botanical composition, reduce soil erosion, optimize animal growth rates and aid ecosystem functions. Managing to critical values for herbage mass is likely to be more effective than efforts to calculate sustainable stocking rates. An early summer rest is valuable for aiding grassland rehabilitation and summer productivity, but a total grazing ban(typically for 5 years)may not achieve its aims as evidence shows it may take 10–15 years to achieve a better grassland state. Lessdesirable plant species often increase in degraded grasslands that are rested and grazing can help manage those species. Surveys of herders indicate they have very mixed views on the benefits of total grazing bans that are unlikely to rehabilitate grasslands to an ideal botanical composition.The current objective is to work with grasslands that herders now have and optimize the existing composition.Grazing grasslands in winter results primarily in weight loss by animals and there is now evidence of how winter grazing reduces grassland growth in the next summer. It is better to keep animals in well-built sheds and feed them better, improved feeding through the cold months is required. In addition to the application of results from national programs designed to improve grasslands, it will be important to train herders as they move from survival to production, to foster the development of better markets for their livestock products, to devise better financial support for herder businesses and to revise land tenure arrangements so that herders can expand the area of land they graze on better terms than apply at present. | David KEMP Guodong HAN Fujiang HOU Xiangyang HOU Zhiguo LI Yi SUN Zhongwu WANG Jianping WU Xiaoqing ZHANG Yingjun ZHANG Xuyin GONG | 2018 | Frontiers of Agricultural Science and Engineering2018，5，1： | 3 |
| 2 | Integrated crop-livestock production systems in China显示文摘 | Hou Fujiang Nan Zhibiao Xie Yingzhong | 2008 | The Rangeland Journal2008，30，2： | 1 |
| 3 | The role of tsunami buoy played in tsunami warning and its application in South China Sea显示文摘The tsunami was a sudden marine disasters.Tsunami waves can quickly spread to near-shore and cause the disaster after the tsunami.So it is very important of timely monitoring and early warning of the tsunami.After several unsuccessful tsunami forecasting,the United States developed tsunami buoy specifically for the early detection of tsunami waves.Tsunami buoy can not only be able to display occurrence of the tsunami,it is real time data but also be assimilated into the tsunami warning system,to improve the accuracy of the tsunami forecasting.Several tsunami events in the recent few years have proven the important role of the tsunami buoys.Subsequently,the tsunami warning system based on tsunami buoys was into regular operation.The system accurately predicted the results on March 11,2011 Japan tsunami event.State Oceanic Administration(SOA),China also deployed 2 tsunami buoys in the South China Sea(SCS),which also played an important role in the warning process of Japan tsunami on March 11,2011.National Marine Environmental Forecasting Center/State Oceanic Administration(NMEFC/SOA) will collaborate with Pacific Marine Environmental Laboratory/National Oceanic and Atmospheric Administration(PMEL/NOAA) to develop assimilation method making use of real time data of tsunami buoy and build a forecasting system in SCS in the future. | Lianda Zhao Fujiang Yu Jingming Hou Peitao Wang Tingting Fan | 2013 | Theoretical & Applied Mechanics Letters2013，3，3： | 1 |
| 4 | 三维土壤异质性对种子萌发影响的实验研究显示文摘种子萌发受其生长环境的影响,但土壤异质性对种子萌发的作用还不太清楚。本文通过控制实验研究了三维土壤异质性对草本植物种子萌发的影响,实验设置了两种水平的土壤异质性,即通过在花盆内的三维空间上相间填充营养丰富和贫瘠两种土壤来构建不同的土壤异质性水平。两种水平土壤异质性的斑块大小分别为7.5和15.0 cm。实验采用两种草本植物(黑麦草Lolium perenne和垂穗披碱草Elymus nutans),每种植物选择大小一致的种子50粒,这些种子要么放在异质性土壤中萌发,要么放在培养皿中萌发。实验过程中,每天统计这些种子的萌发率。实验发现,斑块小的花盆内种子萌发率较低,这个结果与我们的预期相符,我们认为斑块小的花盆内,两种土壤斑块之间的间距较小,植物遭遇不同土壤斑块资源变动的几率较大,植物为了减小这种变动带来的不利影响,会倾向于降低萌发率和延迟萌发。我们的研究还发现,斑块小的花盆内种子萌发的变异性也较大,即与大斑块内的种子萌发率相比,小斑块内的种子萌发率在各重复间的差异性较大。与二维土壤异质性相比,三维土壤异质性更接近于真实情况,这样的土壤设置能够促进我们更好地理解土壤空间异质性对种子萌发等动态过程的影响。 | Yongjie Liu Fujiang Hou | 2021 | Journal of Plant Ecology2021，14，1： | 0 |
| 5 | Observations and modelling of the travel time delay and leading negative phase of the 16 September 2015 Illapel,Chile tsunami显示文摘The systematic discrepancies in both tsunami arrival time and leading negative phase(LNP)were identified for the recent transoceanic tsunami on 16 September 2015 in Illapel,Chile by examining the wave characteristics from the tsunami records at 21 Deep-ocean Assessment and Reporting of Tsunami(DART)sites and 29 coastal tide gauge stations.The results revealed systematic travel time delay of as much as 22 min(approximately 1.7%of the total travel time)relative to the simulated long waves from the 2015 Chilean tsunami.The delay discrepancy was found to increase with travel time.It was difficult to identify the LNP from the near-shore observation system due to the strong background noise,but the initial negative phase feature became more obvious as the tsunami propagated away from the source area in the deep ocean.We determined that the LNP for the Chilean tsunami had an average duration of 33 min,which was close to the dominant period of the tsunami source.Most of the amplitude ratios to the first elevation phase were approximately 40%,with the largest equivalent to the first positive phase amplitude.We performed numerical analyses by applying the corrected long wave model,which accounted for the effects of seawater density stratification due to compressibility,self-attraction and loading(SAL)of the earth,and wave dispersion compared with observed tsunami waveforms.We attempted to accurately calculate the arrival time and LNP,and to understand how much of a role the physical mechanism played in the discrepancies for the moderate transoceanic tsunami event.The mainly focus of the study is to quantitatively evaluate the contribution of each secondary physical effect to the systematic discrepancies using the corrected shallow water model.Taking all of these effects into consideration,our results demonstrated good agreement between the observed and simulated waveforms.We can conclude that the corrected shallow water model can reduce the tsunami propagation speed and reproduce the LNP,which is observed for tsunamis that have propagated over long distances frequently.The travel time delay between the observed and corrected simulated waveforms is reduced to<8 min and the amplitude discrepancy between them was also markedly diminished.The incorporated effects amounted to approximately 78%of the travel time delay correction,with seawater density stratification,SAL,and Boussinesq dispersion contributing approximately 39%,21%,and 18%,respectively.The simulated results showed that the elastic loading and Boussinesq dispersion not only affected travel time but also changed the simulated waveforms for this event.In contrast,the seawater stratification only reduced the tsunami speed,whereas the earth’s elasticity loading was responsible for LNP due to the depression of the seafloor surrounding additional tsunami loading at far-field stations.This study revealed that the traditional shallow water model has inherent defects in estimating tsunami arrival,and the leading negative phase of a tsunami is a typical recognizable feature of a moderately strong transoceanic tsunami.These results also support previous theory and can help to explain the observed discrepancies. | Peitao Wang Zhiyuan Ren Lining Sun Jingming Hou Zongchen Wang Ye Yuan Fujiang Yu | 2021 | Acta Oceanologica Sinica2021，40，11： | 0 |
| 6 | An efficient algorithm for generating a spherical multiple-cell grid显示文摘This paper presents an efficient algorithm for generating a spherical multiple-cell(SMC)grid.The algorithm adopts a recursive loop structure and provides two refinement methods:(1)an arbitrary area refinement method and(2)a nearshore refinement method.Numerical experiments are carried out,and the results show that compared with the existing grid generation algorithm,this algorithm is more flexible and operable. | Fang Hou Zhiyi Gao Jianguo Li Fujiang Yu | 2022 | Acta Oceanologica Sinica2022，41，5： | 0 |
| 7 | Elevated and atmospheric-level methane consumption by soil methanotrophs of three grasslands in China显示文摘Background:Methane(CH4)oxidation driven by soil aerobic methanotrophs demonstrates the capacity of grassland as a CH4 sink.Methods:In this study,we compared the oxidation characteristics of atmospheric-level and elevated concentration(10%)CH4 in a typical grassland(steppe)on the Loess Plateau,an alpine meadow(meadow)on the Qinghai-Tibet Plateau,and an inland arid-area artificial grassland(pasture)in northwest China and investigated the communities of active methanotrophs and their contribution to CH4 oxidation using DNA-based stable-isotope probing and Illumina Miseq sequencing.Results:The results showed that the oxidation of atmospheric CH4 only occurred in steppe and meadow soils where the USCγgroup of methanotrophs was numerically dominant in the methanotroph community.Pasture soils,with their very low relative abundance of USCγ,did not show atmospheric CH4 oxidation.However,a DNA-stable isotope probing experiment with 10%CH4 indicated that conventional CH4 oxidizers(Methylocaldum and Methylocystis)rather than USCγcommunities assimilated significant amounts of 13CH4 for growth.Conclusions:The CH4 oxidation mechanisms in the three experimental grassland soils varied significantly.The USCγgroup may be obligate oligotrophic microorganisms or their growth requires specific unknown conditions. | Yufang Wang Yuanfeng Cai Fujiang Hou Saman Bowatte Zhongjun Jia | 2023 | Grassland Research2023，2，2： | 0 |
| 8 | GRASSLAND AGRICULTURE IN CHINA--A REVIEW显示文摘Interactions between crops and livestock have been at the core of the evolution of many agricultural systems.In this paper,we review the development and characteristics of mixed crop-livestock systems,with a focus on grassland-based systems,as these cover large areas in China,and face several challenges.Following the transition from the original hunting and foraging systems to a sedentary lifestyle with integrated crop-livestock production systems some 8000 years ago,a range of different mixed systems have developed,depending on rainfall,solar radiation and temperature,culture and markets.We describe 5 main types of integrated systems,(1)livestock and rangeland,(2)livestock and grain production,(3)livestock and crop-grassland rotations,(4)livestock,crops and forest(silvo-pasture),and(5)livestock,crops and fish ponds.Next,two of these mixed systems are described in greater detail,i.e.,the mountain-oasis-desert system and its modifications in arid and semi-arid regions,and the integrated crop-livestock production systems on the Loess Plateau.In general,crop-livestock interactions in integrated systems have significant positive effects on crop production,livestock production,energy use efficiency and economic profitability.We conclude that improved integration of crop-livestock production systems is one of the most important ways for achieving a more sustainable development of animal agriculture in China. | Fujiang HOU Qianmin JIA Shanning LOU Chuntao YANG Jiao NING Lan LI Qingshan FAN | 2021 | Frontiers of Agricultural Science and Engineering2021，8，1： | 0 |
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