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Characteristics and influencing factors of CO_(2) emission from inland waters in China

Science China Earth Sciences 2024年第6期67卷 2034-2055页

作者： Ting ZHOU Xiaofeng WANG Zuolin XIAO Zhaoyin QING Xianxiang LI Jilong WANG Ziyi QUE Chongqing Key Laboratory of Carbon Cycling and Carbon Regulation in Mountainous Ecosystems Chongqing 401331China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Chongqing field Observation and Research station of Earth Surface Ecological Processes in Three Gorges Reservoir Area Chongqing 405400China School of Earth System Science Tianjin UniversityTianjin 300072China

Inland water bodies,being the most active biogeochemical cycle reactors,play a pivotal role in the global carbon cycle and CO_(2) *** study integrates existing observation dataset of CO_(2) flux(fCO_(2))in rivers,lakes and reservoirs in China,to elucidate their spatial-temporal patterns and key influencing factors and to reappraise the significance for regional carbon *** showed that,the fCO_(2) in rivers,lakes and reservoirs in China presented significant variability with large range of-379.3-4947.6,-160.1-785.0 and -74.0-1603.1 mg CO_(2)m-2h^(-1),*** median of the fCO_(2) in rivers was of 228.5 mg CO_(2)m^(-2)h^(-1),observably higher than these in lakes and reservoirs(26.0 and 28.3 mg CO_(2)m^(-2)h^(-1),respectively).The fCO_(2)in rivers and reservoirs exhibited similar decreasing trend from south to north as a result of universal climate restraint,the averaged fCO_(2) in Pearl River and Yangtze River basins showed much higher than that in Northeastern ***,the averaged fCO_(2) in the Mongolia-Xinjiang lake district and the Northeast lake district were higher than other lake districts,followed by the Qinghai-Xizang lake district,and the Eastern and Yungui lake district were generally low,contradicting the climatic *** water primary production enhancement resulting from human activities was the main driver of spatial variation in the fCO_(2) in ***,the fCO_(2) in rivers presented seasonal pattern with higher wet season than dry season,while opposite patterns were found in lakes and *** temperature,precipitation and water primary production were main ***,it showed pH was a key factor indicating the variability of the fCO_(2) levels either in rivers,lakes or in *** lakes,the fCO_(2) is closely linked to chlorophyll a(Chl-a)and dissolved oxygen(DO),whereas,the fCO_(2) in rivers is primarily associated with organic carbon(OC)and total nitrogen(TN),highlighting the dive

关键词： rivers/lakes/reservoirs CO_(2) emission Spatio-temporal variability Influence factors Regional contribution

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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet

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Atmospheric and Oceanic Science Letters 2024年第5期17卷 47-53页

作者： Yumeng Liu Xianhong Meng Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina Zoige Plateau wetlands Ecosystem Research station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina University of Chinese Academy of Sciences BeijingChina Utah Climate Center Utah State UniversityLoganUSA The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

Summer precipitation in the Three rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal *** study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer *** empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR *** influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°***,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.

关键词： Summer precipitation East Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection

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Nutrient Use Efficiency of Three Fast Growing Hardwood Species across a Resource Gradient

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open Journal of Forestry 2012年第4期2卷 187-199页

作者： Dawn E. Henderson Shibu Jose Department of Forestry University of Missouri Columbia USA open rivers and wetlands field station Missouri Department of Conservation Jackson USA

Attitudes regarding traditional energy sources have shifted toward renewable resources. Specifically, short-rotation woody crop supply systems have become more prevalent for biomass and biofuel production. However, a number of factors such as environmental and inherent resource availability can limit tree production. Given the intensified demand for wood biomass production, forest and plantation management practices are focusing on increasing productivity. Fertilizer application, while generally one of the least expensive silvicultural tools, can become costly if application rates exceed nutrient uptake or demand of the trees especially if it does not result in additional biomass production. We investigated the effect of water and varying levels of nitrogen application (56, 112, and 224 kg·N·haǃ·yrǃ) on nutrient content, resorption efficiency and proficiency, N:P and the relationship with ANPP, as well as leaf- and canopy-level nutrient use efficiency of nitrogen, phosphorus, and potassium for Populus deltoides, Quercus pagoda, and Platanus occidentalis. P. deltoides and P. occidentalis reached their maximum nitrogen budget with the application of water suggesting old agricultural fields may have sufficient nutrient levels to sustain short-rotation woody crops negating the application of additional nitrogen for these two species. Additionally, for P. deltoides and Q. pagoda application of nitrogen appeared to increase the uptake of phosphorus however, resorption efficiency for these two species were more similar to studies conducted on nutrient poor sites. Nutrient resorption proficiency for all three nutrients and all three species were at levels below the highest rates of nitrogen application. These findings suggest maximum biomass production may not necessarily be tied to maximum nutrient application.

关键词： Nutrient Use Efficiency Resorption N:P Biomass Production

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ASIAN CARP EXPANSION IN THE MISSISSIPPI RIVER:FOCUSING ON THE LEADING EDGE OF THE INVASION FRONT

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水生生物学报 2018年第6期42卷 1075-1080页

作者： TRIPP Sara PHELPS Quinton Big rivers and wetlands field station Missouri Department of Conservation3815 East Jackson BoulevardJacksonMissouri 63755USA West Virginia University Division of Forestry and Natural Resources307C Percival HallMorgantownWest Virginia 26505USA

Asian carp are expanding their range throughout the Mississippi River; however, abundance is thought to be highest in reaches within close proximity to the Illinois River. In the Mississippi River, Lock and Dam 19(L&D 19) at Keokuk, Iowa is the primary barrier to slow the expansion upstream. As Asian carp abundance increases below L&D 19, it is important to investigate potential means of control(i.e., reduction through harvest and barriers) that will prevent complete invasion of the Mississippi River above L&D 19. Silver Carp and Bighead Carp were collected below L&D 19, a subsample were implanted with ultrasonic transmitters to evaluate passage through the lock chamber and the remainder were used to determine population dynamics at the leading edge of invasion. Although the dam portion of the structure poses a complete barrier to upstream expansion, we documented lock chamber passage demonstrating the lock chamber has the capability to provide passage upstream. Based on the results of the population assessment, in order to induce recruitment overfishing at this leading edge of invasion, Asian carp will need to be intensively harvested at 300 mm and larger. The combination of commercial fishing efforts and research investigating ways to prevent passage upstream must be employed.

关键词： Mississippi River remainder

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Response mechanism of soil microorganisms to simulated precipitation in the source wetland of Qinghai Lake

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Ecological Processes 2024年第2期13卷 61-71页

作者： Xinye Wang Ni Zhang Kelong Chen Tiexi Chen Desheng Qi Yuanxi Ma School of Geographical Sciences Qinghai Normal University National Positioning Observation and Research station of Qinghai Lake Wetland Ecosystem in Qinghai National Forestry and Grassland Administration Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal University School of Geographical Sciences Nanjing University of Information Science and Technology Qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in Qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of Qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： Qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

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A RAPID ASSESSMENT APPROACH FOR EVALUATING SILVER CARP GENDER

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水生生物学报 2018年第6期42卷 1081-1083页

作者： WOLF Michael C. PHELPS Quinton E. SEIBERT Justin R. TRIPP Sara J. Department of Natural Resources Fish and Wildlife Division204 Main Street East BaudetteMinnesota 56623USA West Virginia University Division of Forestry and Natural Resources307C Percival HallMorgantownWest Virginia 26505USA Southeast Missouri State University Biology Department 1 University Plaza Cape GirardeauMissouri 63701USA Big rivers and wetlands field station Missouri Department of Conservation3815 East Jackson BoulevardJacksonMissouri 63755USA

Silver carp Hypophthalmichthys molitrix were introduced into the U.S. to control water quality in aquaculture ponds. From this point of origin, silver carp escaped into nearby rivers through multiple flood events. Because of their documented negative effects on native biota, silver carp have been labeled as problematic. Therefore, evaluating the biology and ecology of these non-indigenous species is critical. Multiple parameters are needed to evaluate silver carp populations(length, weight, age, and sex). Furthermore, developing methods for rapidly acquiring these data are needed. In relation to sex determination, sexual dimorphism was observed where males exhibit distinct pectoral fin ray features. Specifically, males have pronounced ridges or a "rough patch" on the dorsal surface of pectoral fins. Therefore, to test if this was an applicable way of determining silver carp gender; silver carp were collected from Midwestern U.S. rivers(N=2015) in the fall of 2011(N=870), spring of 2012(N=645), winter of 2013—2014(N=202) and summer2015(N=323) via electrofishing. For each silver carp collected, presence(e.g., rough patch) or absence(e.g.,smooth) of pronounced ridges on the top side of the pectoral fins was recorded, and an incision was made in the body cavity to identify gender. Based on the results of our evaluation, gender was correctly identified over99% of the time(2006 out of 2015) based on the pectoral fin dimorphism. In the samples taken in the winter of 2013—2014 and summer of 2015, accuracy for silver carp shorter than 300 mm and longer than 800 mm was 53.7%(19 out of 41) while accuracy for silver carp between 300 mm and 800 mm total length was 98.9%(289 out of 292). This study provides a rapid assessment approach for evaluating silver carp gender.

关键词： Invasive species Gender assessment

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Space use of wintering waterbirds in India： Influence of trophic ecology on home-range size

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Current Zoology 2014年第5期60卷 616-621页

作者： Tsewang NAMGAIL John Y. TAKEKAWA Sivananinthaperumal BALACHANDRAN Ponnusamy SATHIYASELVAM Taej MUNDKUR Scott H. NEWMAN U. S. Geological Survey Western Ecological Research Center San Francisco Bay Estuary Field Station 505 Azuar Drive Vallejo California 94592 USA Moss Landing Marine Laboratories 8272 Moss Landing Road Moss Landing California 95039 USA Bombay Natural History Society Mumbai 400 001 India wetlands International NL-6700 AL Wageningen Netherlands Emergency Center for Transboundary Animal Diseases Food and Agriculture Organisation of the United Nations Hanoi Vietnam

Relationship between species＇ home range and their other biological traits remains poorly understood, especially in migratory birds due to the difficulty associated with tracking them. Advances in satellite telemetry and remote sensing techniques have proved instrumental in overcoming such challenges. We studied the space use of migratory ducks through satellite telemetry with an objective of understanding the influence of body mass and feeding habits on their home-range sizes. We marked 26 indi- viduals, representing five species of migratory ducks, with satellite transmitters during two consecutive winters in three Indian states. We used kernel methods to estimate home ranges and core use areas of these waterfowl, and assessed the influence of body mass and feeding habits on home-range size. Feeding habits influenced the home-range size of the migratory ducks. Carnivorous ducks had the largest home ranges, herbivorous ducks the smallest, while omnivorous species had intermediate home-ranges. Body mass did not explain variation in home-range size. To our knowledge, this is the first study of its kind on migratory ducks, and it has important implications for their conservation and management [Current Zoology 60 （5）： 616-621, 2014].

关键词： Anatidae Garganey Gadwall Northern Shoveler Chilika India

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祁连山中部不同海拔青海云杉径向生长对升温的响应分异

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地理学报：英文版 2023年第1期33卷 151-168页

作者：张卫国勾晓华张芬刘文火张赟高琳琳 Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Gansu Liancheng Forest Ecosystem field Observation and Research station Lanzhou UniversityLanzhou 730000China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesCASLanzhou 730000China National Plateau wetlands Research Center Southwest Forestry UniversityKunming 650224China

Understanding the radial growth trends of trees and their response to recent warming along elevation gradients is crucial for assessing how forests will be impacted by future climate ***,we collected 242 tree-ring cores from five plots across the Qinghai spruce(Picea crassifolia Kom.)forest belt(2600–3350 m a.s.l.)in the central Qilian Mountains,Northwest China,to study trends in the radial growth of trees and their response to climate factors with variable *** the sampled *** chronologies showed an increasing trend in the radial growth of trees at higher altitudes(3000–3350 m),whereas the radial growth of trees at lower altitudes(2600–2800 m)has decreased in recent *** radial growth of trees was limited by precipitation at lower elevations(L,ML),but mainly by temperature at higher elevation sites(MH,H,TL).Climate warming has caused an unprecedented increase in the radial growth of *** at higher *** results suggest that ongoing climate warming is beneficial to forest ecosystems at high elevations but restricts the growth of forest ecosystems at low elevations.

关键词： global warming altitudinal gradient Qinghai spruce tree radial growth dendroecology

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Physico-Chemistry of Elechi Creek in the Upper Bonny Estuary, rivers State, Nigeria

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Journal of Geoscience and Environment Protection 2017年第8期5卷 181-197页

作者： Amauche Sabastine Ngah Solomon Braide Collins Chiadi Dike Institute of Geosciences and Space Technology Rivers State University of Science and Technology Port Harcourt Nigeria Institute of Pollution Studies Rivers State University of Science and Technology Port Harcourt Nigeria

The physico-chemistry of tidal Elechi Creek in the upper Bonny Estuary was investigated to assess the toxicity of the water body as this could have adverse effects on the native organisms that form part of the ecosystem and to evaluate the extent and magnitude of petroleum hydrocarbon and heavy metal concentration in the water body. Standard field procedures were adopted in sample collection while laboratory analysis was carried out also following standard methods. Parameters measured include pH, temperature, dissolved oxygen (DO), biological oxygen demand (BOD), electrical conductivity, salinity and total dissolved solids (TDS). Heavy metals namely Copper (Cu), Lead (Pb), Zinc (Zn), nitrate (NO3), sulphate (SO4), Ammonia (NH4), and Total Hydrocarbon Concentration (THC) in the surface water body were also determined on samples collected from five (5) sampling stations spread along the creek in both dry and wet seasons. The results showed that the surface water body is oligohaline with low acidity, pH values ranging from 6.2 to 7.6. Temperature varies from 27°C to 30°C. Dissolved Oxygen (DO) concentration ranges from 2.9 to 7.5 mg/l which is adequate for aquatic organism with Biological Oxygen Demand (BOD) values varying from 0.45 to 7.0 mg/l. The values of total dissolved solids (TDS) vary from 11,700 mg/l to 26,250 mg/l with the highest mean value obtained at the study station located downstream. The mean nutrient concentration showed that the study area is not eutropic. Anthropogenic activities were very high at the sites throughout the period of the study and may have resulted in the stress conditions of the area. Pollution trend along the study stations showed that no one station is unpolluted. The study recommends the introduction of enforceable and stringent waste management plans to highlight and discourage direct discharge of untreated waste and storm water runoff into an aquatic environment.

关键词： Physico-Chemistry Elechi Creek rivers State Nigeria

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Sediment transport under the presence and absence of emergent vegetation in a natural alluvial channel from Brazil

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International Journal of Sediment Research 2016年第4期31卷 360-367页

作者： Yuri Jacques Agra Bezerra da Silva José Ramon Barros Cantalice Vijay P.Singh Cinthia Maria Cordeiro Atanázio Cruz Wagner Luís da Silva Souza Soil Conservation Engineering Laboratory Rural Federal University of Pernambuco(UFRPE) Brazil Department of Biological and Agricultural Engineering Texas A & M University College Station

Studies regarding the influence of emergent vegetation on sediment transport are scarce and have mainly focused on flume *** fill this gap and also meet the international need,we aimed to evaluate the influence of emergent vegetation(Echinodorus macrophyllus) on sediment transport of Capibaribe River,*** and suspended sediment measurements were carried out using the US BLH 84 and US DH 48 samplers,*** of stem diameter,stem spacing and plant density were performed in conjunction with flow and sediment field *** on our results,0.45 m swas the threshold of mean flow velocity supported by *** under field *** value can be helpful for other rivers with gravel-bed river to armoured layer ratio(AR=D)/D=12.50)-natural conditions observed in Capibaribe River-or where the vegetation can provide positive effects,such as increase the bed stability,assist water restoration/rehabilitation and decrease water *** results can hopefully be used in engineering practice and ecosystem *** general,both the drag coefficient and drag force varied inversely and directly with the mean flow velocity and vegetation density,*** vegetation resistance force was inversely proportional to the bedload transport owing to the resistance caused by emergent *** finding was supported by the clear decoupling between nonvegetated and emergent vegetated conditions indicated by cluster *** study results provided a reasonable understanding of the interaction between emergent vegetation,water flow and sediment transport in the Capibaribe River.

关键词： Vegetation drag force Vegetation drag coefficient Plant Reynolds number Hierarchical cluster analysis and principal component analysis

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