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1Energy balance closure at ChinaFLUX sites显示文摘Network of eddy covariance observation is measuring long-term carbon and water fluxes in contrasting ecosystems and climates. As one important reference of independently evaluating scalar flux estimates from eddy covariance, energy balance closure is used widely in study of carbon and water fluxes. Energy balance closure in ChinaFLUX was evaluated by statistical regression of turbulent energy fluxes (sensible and latent heat) against available energy (net radiation, soil heat flux, canopy heat storage) and the energy balance ratio (EBR) and the frequency distribution of relative errors of energy balance (δ). The trends of diurnal and seasonal variation of energy balance in ChinaFLUX were analyzed. The results indicated that the imbalance was prevalent in all observation sites, but there were little differences among sites because of the properties variation of sites. The imbalance was greater during nocturnal periods than daytime and closure was improved with friction velocity intensifying. Generally the results suggested that estimates of the scalar turbulent fluxes of sensible and latent heat were underestimated and/or that available energy was overestimated. Finally, we discussed certain factors that are contributed to the imbalance of energy, such as systematic errors associated with the sampling mismatch, systematic instrument bias, neglected energy sinks, low and high frequency loss of turbulent fluxes and advection of heat and water vapor.LI Zhengquan, YU Guirui, WEN Xuefa, ZHANG Leiming, REN Chuanyou & FU Yuling Chinese Ecosystem Research Network Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:50
2Major element,trace element,and Sr,Nd and Pb iso-tope studies of Cenozoic basalts from the South China Sea显示文摘The whole rock K-Ar ages of basalts from the South China Sea basin vary from 3.8 to 7.9 Ma, which suggest that intra-plate volcanism after the cessation of spreading of the South China Sea (SCS) is comparable to that in adjacent regions around the SCS, i.e., Leiqiong Peninsula, northern margin of the SCS, Indochina block, and so on. Based on detailed petrographic studies, we selected many fresh ba-saltic rocks and measured their major element, trace element, and Sr-Nd-Pb isotope compositions. Geochemical characteristics of major element and trace element show that these basaltic rocks belong to alkali basalt magma series, and are similar to OIB-type basalt. The extent of partial melting of mantle rock in source region is very low, and magma may experience crystallization differentiation and cu-mulation during the ascent to or storing in the high-level magma chamber. Sr-Nd-Pb isotopic data of these basaltic rocks imply an inhomogeneous mantle below the South China Sea. The nature of magma origin has a two end-member mixing model, one is EM2 (Enriched Mantle 2) which may be originated from mantle plume, the other is DMM (Depleted MORB Mantle). Pb isotopic characteristics show the Dupal anomaly in the South China Sea, and combined with newly found Dupal anomaly at Gakkel ridge in Arctic Ocean, this implies that Dupal anomaly is not only limited to South Hemisphere. In variation diagrams among Sr, Nd and Pb, the origin nature of mantle below the SCS is similar to those below Leiqiong peninsula, northern margin of the SCS and Indochina peninsula, and is different from those below north and northeast China. This study provides geochemical constraints on Hainan mantle plume.YAN QuanShu SHI XueFa WANG KunShan BU WenRui XIAO Long 2008Science China Earth Sciences2008,51,4:33
3Terrestrial carbon sinks in China and around the world and their contribution to carbon neutrality显示文摘Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ecosystem C monitoring over broad geographic scale to improve terrestrial biosphere models for accurately evaluating terrestrial C budget and its dynamics under various climate change and policy scenarios.Yuanhe Yang Yue Shi Wenjuan Sun Jinfeng Chang Jianxiao Zhu Leiyi Chen Xin Wang Yanpei Guo Hongtu Zhang Lingfei Yu Shuqing Zhao Kang Xu Jiangling Zhu Haihua Shen Yuanyuan Wang Yunfeng Peng Xia Zhao Xiangping Wang Huifeng Hu Shiping Chen Mei Huang Xuefa Wen Shaopeng Wang Biao Zhu Shuli Niu Zhiyao Tang Lingli Liu Jingyun Fang 2022Science China(Life Sciences)2022,65,5:32
4Petrologic perspectives on tectonic evolution of a nascent basin(Okinawa Trough) behind Ryukyu Arc: A review显示文摘Okinawa Trough is a back-arc, initial marginal sea basin, located behind the Ryukyu Arc–Trench System. The formation and evolution of the Okinawa Trough is intimately related to the subduction process of the Philippine Sea Plate beneath the Eurasian Plate since the late Miocene. The tectonic evolution of the trough is similar to other active back-arcs, such as the Mariana Trough and southern Lau Basin, all of which are experiencing the initial rifting and subsequent spreading process. This study reviews all petrologic and geochemical data of mafic volcanic lavas from the Okinawa Trough, Ryukyu Arc, and Philippine Sea Plate, combined with geophysical data to indicate the relationship between the subduction sources(input) and arc or back-arc magmas(output) in the Philippine Sea Plate–Ryukyu Arc–Okinawa Trough system(PROS). The results obtained showed that several components were variably involved in the petrogenesis of the Okinawa Trough lavas: sub-continental lithospheric mantle underlying the Eurasian Plate, Indian mid-oceanic ridge basalt(MORB)-type mantle, and Pacific MORB-type mantle. The addition of shallow aqueous fluids and deep hydrous melts from subducted components with the characteristics of Indian MORB-type mantle into the mantle source of lavas variably modifies the primitive mantle wedge beneath the Ryukyu and subcontinental lithospheric mantle(SCLM) beneath the Okinawa Trough. In the northeastern end of the trough and arc, instead of Indian MORB-type mantle, Pacific MORB-type mantle dominates the magma source. Along the strike of the Ryukyu Arc and Okinawa Trough, the systematic variations in trace element ratios and isotopic compositions reflect the first-order effect of variable subduction input on the magma source. In general, petrologic data, combined with geophysical data, imply that the Okinawa Trough is experiencing the 'seafloor spreading' process in the southwest segment, 'rift propagation' process in the middle segment, and 'crustal extension' process in the northeast segment, and a nascent ocean basin occurs in the southwest segment.YAN Quanshu SHI Xuefa 2014Acta Oceanologica Sinica2014,33,4:27
5Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene显示文摘AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed.These three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon.The cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate change.Four stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable.LIU ShengFa SHI XueFa LIU YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing 2010Chinese Science Bulletin2010,55,21:25
6Clay mineral composition and their sources for the fluvial sediments of Taiwan Residents rivers显示文摘Located at the collision boundary between the Philippine Sea Plate and the Eurasian Continental Plate,the island of Taiwan is generally recognized as an important example in the MARGINS Program Science Plan and 'source-to-sink' research because of its high tectonic activity,heavy rainfall and unique geography.Large suspended sediment loads are transported to the adjacent ocean by Taiwan Residents rivers every year,making Taiwan an important source of sediments into the adjacent seas and a natural laboratory for studying the systemic movement of fluvial sediments from source to sink.A detailed study on the clay mineral composition of surface sediments collected from the drainage basins of 12 Taiwan Residents rivers using X-ray diffraction methods was conducted.Our results indicated that the clay mineral assemblages consisted dominantly of illite(approximately 73%) and chlorite(approximately 24%),with lesser abundances of kaolinite(approximately 3%) and even lower levels of smectite from the Danshuei River sediments in northwestern Taiwan.The Jhuoshuei River sediments from western Taiwan contained clay mineral assemblages that consisted of illite(approximately 75%) and chlorite(approximately 25%),but they lacked kaolinite and smectite.In southwestern Taiwan,the clay mineral assemblages were dominated by illite(approximately 75%) and chlorite(approximately 23%),but had a low abundance of kaolinite(generally < 2%) and no smectite.The clay mineral assemblages in eastern Taiwan are obviously different from those in western parts of the island.The most noticeable difference is that the average abundance of chlorite in the Hualien River from eastern Taiwan was the highest(approximately 48%) of all the Taiwan Residents rivers.We concluded that,in general,the clay mineral assemblages in Taiwan Residents rivers were mainly composed of illite and chlorite with kaolinite and smectite being scarce,and these trends are different from those in China's mainland rivers.The clay mineral composition shown in this study was primarily determined by the properties of the bedrock,and the differential weathering intensities of the drainage area.The surface sediments in Taiwan's rivers showed a greater abundance of illite and chlorite because the outcropped rocks were mainly composed of Tertiary sedimentary rocks,especially sandstone,shale and slate,and show strong physical weathering.The relatively high relief and more abundant rainfall also caused the clay minerals in the fluvial sediments to be transported to the estuaries down rivers from the mountains and then delivered to the adjacent seas by currents and waves over a shorter time scale.LI ChuanShun SHI XueFa KAO ShuhJi CHEN MinTe LIU YanGuang FANG XiSheng LUE HuaHua ZOU JianJun LIU ShengFa QIAO ShuQing 2012Chinese Science Bulletin2012,57,6:23
7Trend analysis of sediment grain size and sedimentary process in the central South Yellow Sea显示文摘With the method of trend analysis of sediment grain size, the sediment transport trend of the fine-grained sediments area in the central South Yellow Sea was studied. The results demonstrated that there is a sedimentation center around the point of 123.4° E, 35.1°N, and the sediments outside the center are transported to it. The patterns of sediment transportation and deposition in the Yellow Sea should be controlled by cyclonic circulation (including the Yellow Sea Cold Water Mass) and cold water gyre. The study also showed that the method of trend analysis of sediment grain size has prospective utilization in the fine-grained sediment deposited area on large-scale continental shelf.SHI Xuefa CHEN Chunfeng LIU Yanguang REN Hong WANG Huiyan 2002Chinese Science Bulletin2002,47,14:17
8Biomarker reconstruction of phytoplankton productiv-ity and community structure changes in the middle Okinawa Trough during the last 15 ka显示文摘Biomarkers have been widely used to reconstruct phytoplankton productivity and community structure changes, and this method has been applied for the first time in the middle Okinawa Trough during the transition from the last deglaciation to the Holocene. The total content of all marine phytoplankton biomarkers, used as a total productivity indicator, reveals higher productivity during the deglaciation. The ratios of the biomarkers are used as community structure indicators which show that, compared with the Holocene, the contribution from haptophytes decreased while the contributions from diatoms and dinoflagellates increased during the deglaciation. The increased productivity during the deglacia- tion was likely caused by the stronger winter monsoon. Also increased nutrient supply from terrestrial sources contributes to the higher productivity due to lower sea-level, which is consistent with higher terrestrial biomarker (long-chain n-alkanols) content. These changes in the nutrient supply also con- tributed to the community structure changes in the Okinawa Trough.XING Lei ZHAO MeiXun ZHANG HaiLong LIU YanGuang SHI XueFa 2008Chinese Science Bulletin2008,53,16:17
9Turbulence flux measurement above the overstory of a subtropical Pinus plantation over the hilly region in southeastern China显示文摘Continuous turbulence flux measurement using the eddy covariance (EC) technique was made from January 1 to December 31 in 2003 at two and three canopy heights of a subtropical Pinus plantation on the red earth hilly region in southeastern China. To be able to make sure that the measured turbulence flux will equal the net ecosystem/atmosphere exchange, the quality of the data has to be assessed. Three criteria were investigated here, including the power spectra and cospectra analyses, flux variance similarity (integral turbulence test) and energy balance closure. The spectral analyses suggested that above-canopy power spectral slopes for all velocity components and scalars such as CO2, H2O and air temperature followed the expected -2/3 power law in the inertial subrange, and their cospectral slopes were close to -4/3 power law in the inertial subrange. The important contribution of large-scale motions to energy and mass transfer above the canopy at higher measurement level was also confirmed by the spectral analyses. The eddy covariance systems have the ability to resolve fluctuations associated with small-scale eddies and did not induce an obvious underestimation of the measured turbulence flux. The Monin-Obukhov similarity functions for the normalized standard deviation of vertical wind speed and air temperature were well-defined functions of atmospheric stability at two heights above the forest canopy, which indicated that turbulence flux measurements made at two heights were within the surface layer. Nocturnal flux underestimation and departures of this normalized standard deviation of vertical wind speed similarity function from that expected from Monin-Obukhov theory were a function of friction velocity. Thus, an optimal criterion of friction velocity was determined to be greater than 0.2-0.3 m s-1 for nocturnal fluxes so that the eddy covariance flux measurement was under high turbulent mixing conditions. Energy balance closure reached about 72%-81% at the studied site, which was comparable to the 10%-30% of energy imbalance reported in the literature. However, the energy balance closure could be only used as a useful reference criterion.WEN Xuefa, YU Guirui, SUN Xiaomin & LIU Yunfen Chinese Ecosystem Research Network Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:14
10Os isotopic compositions of a cobalt-rich ferromanganese crust profile in Central Pacific显示文摘187Os/188Os ratios in all sub-layers of the Co-rich ferromanganese crust MP5D17 from Line Seamount in Central Pacific have been systematically determined. The 187Os/188Os values in this crust are highly variable, ranging from 0.4262 to 1.0155. From the bottom to the top, the os-mium isotopic ratios of the crust display a regular variation trend, which correlates well with its changes in structure and texture in the vertical profile. In comparison with the evolu-tion curve of Os isotopic composition in seawater over the past 80 Ma, a similar evolution tendency can be found with respect to the Os isotopic composition of the crust in this study. It is preliminarily concluded that the crust MP5D17 began to grow at about 72 Ma, and underwent three growth hiatuses, corresponding to the geological ages of 64, 53 and 37 Ma, respectively.FU Yazhou PENG Jiantang QU Wenjun HU Ruizhong SHI Xuefa DU Andao 2005Chinese Science Bulletin2005,50,18:13
11Seasonal patterns and environmental control of ecosystem respiration in subtropical and temperate forests in China显示文摘Continuous measurement of carbon dioxide exchange using the eddy covariance (EC) technique was made at two ChinaFLUX forest sites including the young subtropical Pinus plantation (Qianyanzhou) and old temperate broad-leaved Korean pine mixed forest (Changbai Mountains) as part of the ChinaFLUX network. Seasonal patterns and environmental control of ecosystem respiration in the subtropical and temperate forests were evaluated by the often-used multiplicative model and Q10 model as a function of temperature and soil water content. The resuits suggested that ( i ) temperature was found to be a dominant factor in the ecosystem respiration, and most of the temporal variability of ecosystem respiration was explained by temperature. However, in the drought-stressed ecosystem, soil water content controlled the temporal variability of ecosystem respiration other than temperature effects, and soil water content became a dominat factor when severe drought affected the ecosystem respiration; (ii) the regression models analysis revealed that in the drier soil, ecosystem respiration was more sensitive to soil moisture than was expressed by the often-used multiplicative model. It was possible to accurately estimate the seasonal variation of ecosystem respiration based on the Q10 model; and (iii)annual ecosystem respiration derived from the often-used multiplicative model was 1209 g C m-2and 1303 g C m-2, and was consistently a little higher than the Q10 model estimates of 1197 g C m-2 and 1268 g C m-2 for Qianyanzhou and Changbai Mountains, respectively.YU Guirui, WEN Xuefa, LI Qingkang, ZHANG Leiming, REN Chuanyou, LIU Yunfen & GUAN Dexin Chinese Ecosystem Research Network Synthesis Research Center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 2005Science China Earth Sciences2005,48,z1:13
12Seasonal variation of CO_2 flux and its environmental factors in evergreen coniferous plantation显示文摘The effects of environmental factors on carbon flux were analyzed, the spatial and temporal variation of carbon flux was studied at the two heights of 23 m and 39 m with the eddy covariance technique, and the carbon budget was evaluated for evergreen coniferous plantation in the red earth hilly area during the year 2003. The results showed that photosynthetically active radiation (PAR) and soil temperature are essential factors strongly affecting the net ecosystem exchange (NEE); in the daytime, the response of NEE to PAR shows a rectangular hyperbola trend, and in the nighttime, the significant correlation was observed between soil temperature and soil respiration which was filtered using friction velocity. This ecosystem appeared as a carbon sink along the whole year of 2003, and the carbon flux showed the obvious seasonal fluctuation and diurnal variability. The seasonal peak of NEE occurred in May and June with the daily sum about 0.61-0.67 mg · CO2 · m-2 · s-1. For the severe drought in the mid-summer, the daily sum was 0.40-0.44 mg · CO2 · m-2 · s-1 in July which was only 2/3 of that in the last two months. For the lasted drought of the year, the nadir of NEE happened in the winder with the daily sum about -0.29 to -0.35 mg · CO2 · m-2 · s-1. The sink intensity of the ecosystem was about -0.553 to -0.645 kg · Cm-2 per year in 2003.LIU Yunfen, SONG Xia, YU Guirui, SUN Xiaomin, WEN Xuefa & CHEN Yongrui Institute of Geographic Sciences and Natural Resources Research, Chinese Academy Sciences, Beijing 100101, China Graduate School of the Chinese Academy of Sciences, Beijing 10039, China 2005Science China Earth Sciences2005,48,z1:13
13Major and trace element geochemistry of the mid-Bay of Bengal surface sediments: implications for provenance显示文摘The major and trace elements in 110 surface sediment samples collected from the middle of the Bay of Bengal(mid-Bay of Bengal) are analyzed to investigate provenance. Si levels are highest, followed by Al, and the distributions of these two elements are identical. The average CIA*(chemical index of alteration) value is 72.07,indicating that the degree of weathering of the sediments in the study area is intermediate between those of sediments of the Himalayan and Indian rivers. Factor analyses and discrimination function analyses imply that the two main provenances are the Himalayan and the Indian continent. The inverse model calculation of the Tinormalized element ratios of the Bay of Bengal sediments indicate an estimated average contribution of 83.5%and 16.5% from the Himalayan and peninsular Indian rivers to the study area, respectively. The Himalayan source contributes more sediment to the eastern part of the study area, whereas the western part receives more sediment from the Indian Peninsula than did the eastern part. The primary mechanisms for deposition of sediments in the study area are the transport of Himalayan matter by turbidity currents and river-diluted water and the transport of Indian matter to the study area by a surface circulation in the Bay of Bengal, particularly the East India Coastal Current.LI Jingrui LIU Shengfa FENG Xiuli SUN Xingquan SHI Xuefa 2017Acta Oceanologica Sinica2017,36,3:12
14Potassium-argon/argon-40-argon-39 geochronology of Cenozoic alkali basalts from the South China Sea显示文摘Based on the isotopic chronologic results of Cenozoic alkali basalts from the South China Sea, the characteristics of volcanic activity of the South China Sea after spreading were studied. The potassium-argon ages of eight alkali basalt samples from the South China Sea, and the argon-argon ages of two samples among them are reported. Apparent ages of the whole rock are 3.80 to 7.91 Ma with an average value of 5.43 Ma (potassium-argon, whole rock), and there is little difference among samples at the same location, e.g., 4.76~5.78 Ma for location S04-12. The argon-argon ages for the two samples are 6.06 and 4.71 Ma, which lie within the age scope of potassium-argon method. The dating results indicate that rock-forming age is from late Miocene to Pliocene, which is consistent with erupting event for alkali basalts from adjacent regions of the South China Sea. Volcanic activities occur after the cessation of spreading of the South China Sea, which are controlled by lithospheric fault and the spreading center formed during the spreading period of the South China Sea. These dating results, combined with geochemical characteristics of these basalts, the published chronological data for the South China Sea and its adjacent regions, and the updated geophysical data near Hainan Island, suggest that after the cessation of spreading of the South China Sea, there occur widely distributing magmatic activities which primarily is alkali basalt, and the volcanic activity continues to Quaternary. The activity may be relative to Hainan mantle plume originated from core/mantle boundary.YAN Quanshu SHI Xuefa YANG Yaomin WANG Kunshan 2008Acta Oceanologica Sinica2008,27,6:11
15The Limiting Effect of Deep Soil Water on Evapotranspiration of a Subtropical Coniferous Plantation Subjected to Seasonal Drought显示文摘Seasonal drought is a common occurrence in humid climates. The year 2003 was the driest year during the period 1985– 2011 in southeastern China. The objective of this study was to elucidate the impact of the exceptional drought in 2003, compared with eddy flux measurements during 2004–11, on the dynamics of evapotranspiration(ET) and related factors, as well as their underlying mechanisms, in a subtropical coniferous plantation in southeastern China. It was found that daily ET decreased from 5.34 to 1.84 mm during the intensive drought period and recovered to 4.80 mm during the subsquent recovering drought period. Path analysis indicated that ET was mainly determined by canopy conductance and deep soil water content(50 cm) during the intensive drought and recovering drought periods, respectively. The canopy conductance offset the positive effect of air vapor pressure deficit on ET when suffering drought stress, while the canopy conductance enhanced the positive effect of air temperature on ET during the late growing season. Because the fine roots of this plantation are mainly distributed in shallow soil, and the soil water in the upper 40 cm did not satisfy the demand for ET, stomatal closure and defoliation were evident as physiological responses to drought stress.TANG Yakun WEN Xuefa SUN Xiaomin ZHANG Xinyu WANG Huimin 2014Advances in Atmospheric Sciences2014,31,2:11
16Internet of Things to network smart devices for ecosystem monitoring显示文摘Smart, real-time, low-cost, and distributed ecosystem monitoring is essential for understanding and managing rapidly changing ecosystems. However, new techniques in the big data era have rarely been introduced into operational ecosystem monitoring, particularly for fragile ecosystems in remote areas.We introduce the Internet of Things(IoT) techniques to establish a prototype ecosystem monitoring system by developing innovative smart devices and using IoT technologies for ecosystem monitoring in isolated environments. The developed smart devices include four categories: large-scale and nonintrusive instruments to measure evapotranspiration and soil moisture, in situ observing systems for CO2 and d13 C associated with soil respiration, portable and distributed devices for monitoring vegetation variables, and Bi-CMOS cameras and pressure trigger sensors for terrestrial vertebrate monitoring. These new devices outperform conventional devices and are connected to each other via wireless communication networks. The breakthroughs in the ecosystem monitoring IoT include new data loggers and longdistance wireless sensor network technology that supports the rapid transmission of data from devices to wireless networks. The applicability of this ecosystem monitoring IoT is verified in three fragile ecosystems, including a karst rocky desertification area, the National Park for Amur Tigers, and the oasis-desert ecotone in China. By integrating these devices and technologies with an ecosystem monitoring information system, a seamless data acquisition, transmission, processing, and application IoT is created. The establishment of this ecosystem monitoring IoT will serve as a new paradigm for ecosystem monitoring and therefore provide a platform for ecosystem management and decision making in the era of big data.Xin Li Ning Zhao Rui Jin Shaomin Liu Xiaomin Sun Xuefa Wen Dongxiu Wu Yan Zhou Jianwen Guo Shiping Chen Ziwei Xu Mingguo Ma Tianming Wang Yonghua Qu Xinwei Wang Fangming Wu Yuke Zhou 2019Science Bulletin2019,64,17:10
17Geological comparative studies of Japan Arc System and Kyushu-Palau Arc显示文摘Based on the published data of structure geology,geochronology,petrology and isotope geochemistry,the authors of this paper have conducted studies on the tectonic evolution history of Japan arc system and Kyushu-Palau ridge(KPR) . The studies show that the initial Japan arc system was resulted from the subduction of ancient Pacific plate beneath Eurasian Plate in Permian. It was part of an Andean-type continental volcanic arc which occurred in the offshore in the east of Asian during late Mesozoic era. The formation of tertiary back-arc basin(Japan Sea) resulted in the fundamental tectonic framework of the present arc system. Since Quaternary the system has been lying at E-W compression tectonic setting due to the eastward subduction of Amur Plate. It is expected that Japan arc system will be juxtaposed with Asian continent,which is similar to the present Taiwan arc system. The origin of Philippine Sea Plate(PSP) is still in debate. Some studies argued that it is a trapped oceanic crust segment,while the others insisted that it is a back-arc basin accompanied with ancient IBM arc. However,it is all agreed that the tectonic evolution of PSP started since 50 Ma,i.e.,PSP has drifted from the site around equator at 50 Ma to the present site,and the subduction of PSP along Nankai trough-Ryukyu Trench beneath the Japan arc system during 6-2 Ma led to the formation of the present Ryukyu arc system. Of the PSP,the KPR has been found with the oldest rocks formed at 38 Ma. Combining with its geochemical characteristics of oceanic arc tholeiite,it is suggested that KPR is an intraoceanic volcanic arc,more specifically,a relic arc(i.e.,rear arc of the ancient IBM) after rifting of ancient IBM. In addition,Amami-Daito province is of arc tectonic affinity,but has been affected by mantle plume. Therefore,based on their respective tectonic evolution history and geochemical characteristics of rock samples,it is inferred that there is no genetic relationship between Japan arc system and KPR. It is noted that rocks reflecting continental crust basement feature have been collected on the northern tip of KPR,which may be related to the process of KPR accreting on Japan arc,but the arc-continent accretion process are still at initial stage of modern continental crust accretion model. However,due to the scarcity of data of the northern tip of KPR,crustal structure of this location and its adjacent Nankai trough need to be further constrained by geophysical studies in the future.YAN Quanshu SHI Xuefa 2011Acta Oceanologica Sinica2011,30,4:10
18Short-term variations of vapor isotope ratios re- veal the influence of atmospheric processes显示文摘大气的水蒸汽的稳定的同位素在空气在水运动和阶段变化上揭示富有的信息。这里,我们介绍了 D 的二将近连续的时间系列和测量在的大气的水蒸汽(v ) 的 18O 时时,在表面的间隔在在原处使用测量的 Shijiazhuang 在北京并且在一顶冬季小麦华盖上面通风技术。在降水事件期间,在北京和 Shijiazhuang 的 v 价值处于有降水水的平衡的状态,揭示降水过程的影响。然而,来自平衡状态的 v 离开断然与本地相对湿度被相关。注意 v 趋于在北京充实,但是在降水事件期间在 Shijiazhuang 弄空,它主要源于在 Shijiazhuang 充实 v 的蒸发过程的影响。在季节的时间规模上, v 值是在北京和 Shijiazhuang 混合比率的水蒸汽的木头线性的函数。混合比率的水蒸汽是由瑞利蒸馏机制的 v 的一个优秀预言者,显示空气团移流能也起在决定 v 的一个重要作用。在上一日报时间规模, v 与边界层乘火车的大气的过程有关仔细在是的北京在早下午小时到达了最小。在种冬季小麦的季节的山峰期间,然而, v 在清早到达了最小,并且整个白天逐渐地增加了,并且在迟了的下午到达了最大值,它由在边界层乘火车和本地大气的过程之间的相互作用是负责的,例如蒸发和露水形成。这研究在决定表面 v 为植被的重要角色有含意并且加亮需要进行 v 测量在上短期(例如日报) 时间规模。ZHANG Shichun SUN Xiaomin WANG Jianlin YU Guirui WEN Xuefa 2011Journal of Geographical Sciences2011,21,3:10
19Testing the mantle plume hypothesis: an IODP effort to drill into the Kamchatka-Okhotsk Sea basement显示文摘The great mantle plume debate(GPD) has been going on for ~15 years(Foulger and Natland, 2003;Anderson, 2004; Niu, 2005; Davies, 2005; Foulger, 2005; Campbell, 2005; Campbell and Davies, 2006),centered on whether mantle plumes exist as a result of Earth's cooling or whether their existence is purely required for convenience in explaining certain Earth phenomena(Niu, 2005). Despite the mounting evidence that many of the so-called plumes may be localized melting anomalies, the debate is likely to continue. We recognize that the slow progress of the debate results from communication difficulties.Many debaters may not truly appreciate(1) what the mantle plume hypothesis actually is, and(2) none of the petrological, geochemical and geophysical methods widely used can actually provide smoking-gun evidence for or against mantle plume hypothesis. In this short paper, we clarify these issues, and elaborate a geologically effective approach to test the hypothesis. According to the mantle plume hypothesis, a thermal mantle plume must originate from the thermal boundary layer at the core-mantle boundary(CMB), and a large mantle plume head is required to carry the material from the deep mantle to the surface. The plume head product in ocean basins is the oceanic plateau, which is a lithospheric terrane that is large(1000's km across), thick(>200 km), shallow(2–4 km high above the surrounding seafloors), buoyant(~1% less dense than the surrounding lithosphere), and thus must be preserved in the surface geology(Niu et al., 2003). The Hawaiian volcanism has been considered as the surface expression of a type mantle plume, but it does not seem to have a(known) plume head product. If this is true, the Hawaiian mantle plume in particular and the mantle plume hypothesis in general must be questioned. Therefore, whether there is an oceanic plateau-like product for the Hawaiian volcanism is key to testing the mantle plume hypothesis, and the Kamchatka-Okhotsk Sea basement is the best candidate to find out if it is indeed the Hawaiian mantle plume head product or not(Niu et al., 2003; Niu, 2004).Yaoling Niu Xuefa Shi Tiegang Li Shiguo Wu Weidong Sun Rixiang Zhu 2017Science Bulletin2017,62,21:8
20Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea显示文摘The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172 surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 30 μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe River.Section L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East China Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are high.At the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.GE Shulan~(1,2,3), SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography, State Oceanic Administration. Qingdao 266061. China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029. China 3. Graduate School. Chinese Academy of Sciences, Beijing 100039. China 2003Chinese Science Bulletin2003,48,B06:8
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