Yang Gao

• Chinese Academy of Sciences

Inland waters (lakes, reservoirs, and rivers) serve as important regulators of global climate change and carbon (C) cycling. China's inland water systems significantly regulate regional C budgets. However, our understanding of the long-term spatiotemporal patterns and underlying mechanisms of dissolved carbon (DC) storages and fluxes in inland wate...

Background Anthropogenic activities have led to increased N input and changes of N transformation processes in lake systems. However, changes in phytoplankton community structure caused by phytoplankton’s preference for N utilization under the increasing N input remain poorly understood. This study used nitrate isotopes (δ ¹⁵ N-NO 3 ⁻ and δ ¹⁸ O-NO...

Inland water carbon (C) cycling processes determine C source-sink stability status. ■ Metabolic C processes drive carbon source-sink instability in inland waterbodies. ■ Insights into metabolic C processes are key to quantifying C budgets globally. BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Citation: Jia J., Dungait J., L...

Background and aims The accumulation of soil organic carbon (SOC) is a crucial process in mitigating climate change and ensuring soil quality. Subtropical plantations in China have shown high potential for enhancing SOC sequestration due to their high carbon sink capacity. However, the dynamics and compositions of SOC after long term afforestation...

The evasion of carbon dioxide (CO2) from lakes significantly influences the global carbon equilibrium. Amidst global climatic transformations, the role of Qingzang Plateau (QZP) lakes as carbon (C) sources or sinks remains a subject of debate. Furthermore, accurately quantifying their contribution to the global carbon budget presents a formidable c...

Lakes and reservoirs act as active carbon (C) reactors and regulators. Both play a crucial terrestrial ecosystem C balance role via carbon dioxide (CO2) exchange processes across the water-air interface. It has previously been confirmed that CO2 flux from lakes and reservoirs generally exhibits significant spatiotemporal heterogeneity. Nevertheless...

Due to their complexity, inland water carbon (C) cycling processes significantly impact the C source-sink stability status of terrestrial ecosystems over short-term, long-term, and geological timescales. Stable C source-sink processes primarily include terrestrial biospheric production, lithospheric organic carbon (OC) oxidization, rock weathering,...

Studies have suggested that, globally, lake and reservoir systems constitute large carbon (C) sources. However, the drawdown zone where certain lake areas subject to water level fluctuations temporarily dry out, exposing sediment to the atmosphere, needs to be considered in lake-based C sink/source quantitative assessments. This study incorporates...

In recent decades, anthropogenically-driven climate change has affected phytoplankton growth and has widened the differences observed among the gross primary productivity of waterbodies (WGPP) in global lake systems. Results from this study showed that the range of WGPP increased over time (from 1950 to 2020). However, the median WGPP of global inl...

Half of all of China’s lakes are on the Qinghai–Tibet Plateau (QTP), which are mainly distributed at altitudes above 4000 m asl. Being under conditions of progressively intensifying anthropogenic activities and climate change, the debate on whether QTP lakes act as carbon (C) sinks or sources remains unresolved. This study explores QTP lake C excha...

The strong hydrological characteristics and complex biochemical environment of floodplain lake systems make it difficult to obtain accurate, convincing results from sediment pigments used as paleoenvironmental indicators. Understanding pigment migration and preservation mechanisms under hydrological regulation will help explain past ecological chan...

Lake carbon (C) cycling is a key component of the global C cycle and associated C source and sink processes. The partial pressure of carbon dioxide (pCO2) and carbon dioxide (CO2) exchange flux at the lake-air interface (Fc) are controlled by complex physical, chemical, and biological mechanisms. It would be instructively significant to determine w...

Phytoplankton primary productivity from the surface to the euphotic depth (PPeu) is an important indicator for estimating the carbon (C) sequestration capacity of a lake system. Approximately 50% of China's lake systems are distributed throughout the Tibetan Plateau (TP), playing an important C neutrality role in China and beyond. Over the past 20...

In terrestrial ecosystems, carbon (C) transportation and C pool transformation processes both occur at the land-river-estuary continuum. Moreover, C budget and C balance processes are generally critical in achieving the C neutrality of terrestrial ecosystems. This study analyzes key C transportation processes at multiple interfaces that collectivel...

Phytoplankton contribute approximately 50% to the global photosynthetic carbon (C) fixation. However, our understanding of the corresponding C sequestration capacity and driving mechanisms associated with each individual phytoplankton taxonomic group is limited. Particularly in the hydrologically dynamic system with highly complex surface hydrologi...

Carbon (C) and silicon (Si) are essential lake ecosystem components, impacting both phytoplankton growth and other available elements and nutrients. In this study, we selected a typical floodplain-lake system to explore the seasonal role of coupled C and Si as matter is imported and exported through lotic water processes. Results showed considerabl...

Trace metal concentrations in lake systems may inhibit or promote phytoplankton growth and associated community structure factors, subsequently affecting their gross primary production (GPP). Accordingly, this study investigates trace metals and their associated effects on community structure in Qinghai–Tibet Plateau (QTP) lake systems along with e...

High atmospheric dry and wet deposition of dissolved organic carbon (DOC) may contribute to net ecosystem carbon balance (NECB), but the input and output fluxes of DOC and their transport processes in a catchment remain unclear. Here, to elucidate the importance of DOC in NECB from the view of Earth’s critical zone, we measured the water fluxes of...

Viruses act as “regulators” of the global carbon cycle because they impact the material cycles and energy flows of food webs and the microbial loop. The average contribution of viruses to the Earth ecosystem carbon cycle is 8.6‰, of which its contribution to marine ecosystems (1.4‰) is less than its contribution to terrestrial (6.7‰) and freshwater...

Regional processes on land-water-air interface carbon (C) budget and balance that interconnect the land and sea are in fact C neutrality critical processes within the earth system. It is therefore essential to quantitatively analyze synergistic land-water-air interface C transport and C exchange processes to gain a deep understanding of the importa...

Particulate organic carbon (POC) is an important component of lake organic carbon (C) pools, of which different factors drive vertical distributions and sources. This study used the dual stable isotope (δ¹³C and δ¹⁵N) approach to investigate vertical POC sources and drivers in a large floodplain lake system. Findings showed that POC composition gra...

On the Qinghai–Tibet Plateau (QTP), salinity, area, and altitude are the three main environmental gradients, and they are also likely to be the main influencing factors of lake water and carbon (C) sources. We collected water samples from lake and river systems on the QTP to determine their associative physical, chemical, biological, and isotopic i...

Carbon (C) assimilation is primarily dominated by gross primary production (GPP), which is largely limited by nitrogen (N) availability in terrestrial and aquatic ecosystems. Atmospheric N deposition alters the N availability in terrestrial and aquatic ecosystems and regulates C and water cycling processes, including water use efficiency (WUE). Thi...

The Qinghai-Tibet Plateau is the highest and largest plateau in the world and is composed of the world’s greatest clustering of plateau lake systems. Given their extreme environmental conditions and simplistic trophic structures, certain phytoplankton species endemic to these lakes are extremely sensitive to changes in nutrients. Understanding the...

Monitoring from 2016 to 2018 was used to investigate seasonal variation of chemical characteristics and define the water quality status within a subsurface river system in a karst region of Southwest China. For this, the water quality index (WQI) and principal component analysis (PCA) were employed. Results showed that baseflow and constituents, i....

Being a fundamental property of aquatic systems, gross primary productivity (GPP) is affected by complex environmental factors, such as salinity, nutrients, pH, and sunlight. Under conditions of intensified anthropogenic activity and climate change, it is critical to understand the driving mechanisms of GPP in alpine lakes. In this study, we invest...

A floodplain lake system can be described as a water conveyance-type lake system that is subject to high water-level fluctuations (WLFs). This study investigated the effects of WLF on the nutrient status and the gross primary productivity (GPP) of phytoplankton in Lake Poyang, a large floodplain-lake system in China. This study hypothesized that WL...

After carbon (C) enters a lake through surface runoff and atmospheric deposition, most of it, being influenced by the environmental conditions of the basin, is deposited into lake sediment, thus, becoming one of the most important C pools in the world. Therefore, it is critical to understand sediment response characteristics under the context of in...

Most of the world’s lakes are fed through water conveyance, namely, lakes that continuously receive and discharge water. However, the complex hydrological processes of such lakes make it difficult to determine their specific biogeochemical carbon (C) cycles. Poyang Lake was selected for this study, whose capacity to receive and discharge through wa...

In this study, we explore the relationship between changes in chlorophyll a (Chl a) content, total nitrogen (TN) and total phosphorus (TP) characteristics from 1989 to 2018 in Poyang Lake, China, by applying Landsat Thematic Mapper/Enhanced Thematic Mapper (TM/ETM) image data in combination with in situ monitoring data. Results showed that the aver...

Inland water carbon (C) sequestration rates play a potentially important role in the balance between C supplies from the atmosphere and associated watersheds and the net demand of primary producers. This study conducts a comprehensive analysis of influencing factors associated with inland water C cycling processes as well as their C sequestration p...

In this study, a cascaded watershed system in the Poyang Lake area was selected as the study site, which ranged from the primary tributaries to the lake area (Xiangxi River→Jiazhu River→Ganjiang River→Poyang Lake). The aims of the study were to monitor the P wet deposition and runoff process in the Poyang Lake area and discuss the P transport chara...

Bibliometrics was used to statistically analyze key zones within the Yangtze River Basin (YRB) funded by the National Natural Science Foundation of China (NSFC) and national ministries over the past 20 years. This study determined that funds that derived from national ministries have mainly focused on issues related to environmental pollution, ecol...

The magnitude of mass flux is closely associated with biogeochemical watershed processes, which can generate a considerable amount of pertinent information. Moreover, both the accuracy and precision of mass flux estimation results directly affects the perception of the ecological environmental status, which in turn affects both the formulation and...

Understanding land-use change accompanied by anthropogenic activities under alterations in watershed size regulations or differential carbon (C) isotope characteristics remain a challenge in C cycling research. In this study, we investigate changes in the export of C composition and its isotopic characteristics at multiple scales in a subtropical c...

The management of river-lake systems is hindered by limitations in the applicability of existing models that describe the relationship between environmental factors and phytoplankton community characteristics but rarely include common and indirect effects on algae dynamics. In this study, we assumed that the interaction of light, water, temperature...

Silicon (Si) and carbon (C) can couple at different timescales. Phytolith carbon fixation and silicate weathering are two key processes of this type of coupling. Silicate rock weathering sequesters CO2 and thus generates a net C sink, which is one way that C is removed from ecosystems. This study selected the Xiangxi River watershed as the research...

Forests are important components of the terrestrial ecosystem that play major roles in carbon cycling and associated environmental changes, but more knowledge of the processes involved is required. Therefore, carbon wet deposition and rainfall-runoff processes were examined, as well as carbon fluxes and sources in water in the Xiangxi River watersh...

Phytoplankton community characteristics and associative primary productivity, which reflect the ecological and nutritional status of water, are sensitive to environmental change. Particularly, nutrient inputs have a significant effect on phytoplankton growth and development as well as the biogeochemical cycle of watersheds. We investigated the phyt...

In the past three decades, China has built more than 87 000 dams with a storage capacity of ≈6560 km 3 and the total surface area of inland water has increased by 6672 km 2. Leaching of N from fertilized soils to rivers is the main source of N pollution in China, but the exposure of a growing inland water area to direct atmospheric N deposition and...

In this study, a connected waterflow watershed system in the Poyang Lake area was selected as the study site, which ranged from the primary tributary to the lake area (Xiangxi River Jiazhu River Ganjiang River Poyang Lake). The aims of the study were to monitor different forms of C and N and evaluate the transport flux of C and N, and then, the tra...

Covering extensive parts of China, karst is a critically important landscape that has experienced rapid and intensive land use change and associated ecosystem degradation within only the last 50 years. In the natural state, key ecosystem services delivered by these landscapes include regulation of the hydrological cycle, nutrient cycling and supply...

Transportation of carbon and nitrogen during rainfall events is highly important within karst ecosystems and has particular relevance to understand decoupling relation between carbon and nitrogen cycles. The ability of the karst ecosystem to sequester carbon is currently unknown but has potential to be an important residual terrestrial carbon sink....

This study used carbon (C) isotope sourcing to determine transport processes of dissolved inorganic carbon (DIC) from the land surface to river catchments in Southwest China. Both nested karst watersheds investigated (Chenqi and Houzhai) are representative of typical karst landform environments (e.g., primary forest, secondary forest, and farmland)...

Dissolved inorganic carbon (DIC) and Dissolved organic carbon (DOC) are important indices to study karstification, carbon sink and carbon cycle. In order to further know the migration characteristics of DIC and DOC in karst springs in small watersheds and improve the estimation accuracy of carbon flux under the condition of discrete and limited wat...

Anthropogenic activities strengthen atmospheric reactive nitrogen (Nr) emission and deposition, which led to aggravate nitrogen (N) pollution and change gross primary productivity (GPP) in waterbodies. Over the past three decades, the annual Nr deposition over China increased by approximately 25% and the rate of Nr deposition nationwide increased f...

Phytolith-occluded organic carbon (PhytOC) is considered one of the most promising terrestrial carbon (C) sinks. Different methods are used for phytolith extraction from wet-ashing techniques and the subsequent determination of PhytOC content from soil. This is in order to optimize the wet-ashing techniques and to improve estimation accuracy of C s...

In karst areas, rock dissolution often results in the development of underground networks, which act as subterranean pathways for rapid water and nutrient (and possibly soil) loss during precipitation events. Loss of soluble nutrients degrades surface soils and decreases net primary productivity, so it is important to establish flow pathways and qu...

The increasingly fragile ecological environment and associative nitrogen (N) biogeochemical cycle have become critical environmental and ecological issues in China's Loess Plateau. However, N flow and N source for typical catchments remains poorly understood in the Loess Plateau. In this study, we measured concentrations and isotopic signatures of...

Soil is the largest organic carbon (C) pool in terrestrial ecosystems. Periodic changes in environmental temperature occur diurnally and seasonally; yet, the response of soil organic matter (SOM) decomposition to varying temperatures remains unclear. In this study, we conducted a modified incubation experiment using soils from 16 forest ecosystems...

It is important to accurately estimate terrestrial ecosystem carbon (C) storage. However, the spatial patterns of C storage and the driving factors remain unclear, owing to lack of data. Here, we collected data from literature published between 2004 and 2014 on C storage in China's terrestrial ecosystems, to explore variation in C storage across di...

Composition and stability of soil organic matter (SOM) affect the sustenance and productivity of soil over the long-term. This issue is particularly important for karst regions in China where the water supply and fertilizer use are limiting factors. Here, we used four indicators to evaluate changes in the composition and stability of SOM quantitati...

Atmospheric acidic deposition in subtropical watersheds poses an environmental risk of causing acidification of aquatic ecosystems. In this study, we evaluated the frequency of acid deposition in a subtropical forest ecosystem and the associated critical loads of acidity for a sensitive aquatic ecosystem. We found that out of 132 rainfall events, 3...

Karst topography covers more than 1/3 of the People's Republic of China in area. The porous, fissured, and soluble nature of the underlying karst bedrock (primarily dolomite and limestone) leads to the formation of underground drainage systems. Karst conduit networks dominate this system, and rainfall takes a crucial role on water cycle at China ka...

The karst critical zone is an essential component of the carbon (C) pool, constituting the global C cycle. It is referred to as one of the “residual land sink” that remains largely indeterminate. Karst area (2.2×10⁷ km²) comprises 15% of the world’s land area, and karst area comprises 3.44×10⁶ km² of area in China. Due to the complexity of karst st...

carbon (C), nitrogen (N) and phosphorus (P) are three of the most important elements for estimating ecosystem biogenic elements status and algal growth. Therefore, the C:N:P ecological stoichiometry serves as an important reference to guide water quality management and helps elucidate the aquatic ecosystems mechanism. This study firstly provides th...

Atmospheric phosphorus (P) deposition is not only an important external macronutrient source for aquatic ecosystems but also a major cause of high export coefficient (EC) values. However, there are limited numbers of studies in the literature that focus on estimating the deposition flux of reactive P (Pr). The aim of this study is to estimate the P...

Atmospheric wet deposition of nitrogen (N) is an important process in global N cycling, having significant impacts on both water quality and aquatic ecosystems worldwide. The aims of this study were to clarify the N wet deposition first flush effect and estimate the contribution of N wet deposition on both N export and water quality in a subtropica...

Rivers play an important role in carbon (C) exchange between terrestrial and oceanic water bodies and the atmosphere. The aim of this study was to systematically quantify fluxes in riverine C export and C exchange in the air–sea interface of marine ecosystems in China. Results show that annual C transport from rivers to coastal ecosystems in China...

In order to better understand air pollution in deve-loping regions, such as China, it is important to investigate the wet deposition behavior of atmospheric trace metals and its sources in the subtropical watershed. This paper studies the seasonal change of trace metal concentrations in precipitation and other potential sources in a typical subtrop...

Eddy Covariance technique (EC) achieves the direct measurement on ecosystem carbon, nitrogen and water fluxes, and it provides scientific data for accurately assessing ecosystem functions in mitigating global climate change. This paper briefly reviewed the construction and development of Chinese terrestrial ecosystem flux observation and research n...

The C sequestration in coastal blue carbon (Cb) ecosystems, including mangroves, seagrasses and saltmarshes, was discovered to be useful in mitigating the increasing trend of carbon dioxide (CO2) emission due to climate change. In this study, we systematically estimate traditional Cb ecosystem distribution and the associated Cb sequestration rate,...

Soil organic matter is one of the most important carbon (C) pools in terrestrial ecosystems, and future warming from climate change will likely alter soil C storage via temperature effects on microbial respiration. In this study, we collected forest soils from eight locations along a 3,700 km North–South transect in eastern China (NSTEC). For eight...

The aims of this study are (1) to discuss the mechanism of nanoparticle lifecycle and estimate the impacts of its associated pollution on environment and human health; and (2) to provide recommendation to policy makers on how to leverage nanopollution and human health along with the rapid development of economics in China. Manufactured nanoparticle...

Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under vari...

Accurate estimation of soil organic carbon (SOC) storage is important for evaluating carbon sequestration of terrestrial ecosystems at regional scale. How the selected pedotransfer functions (PTFs) of bulk density (BD) influence the estimates of SOC storage is still unclear at large scales, although BD is an important parameter in all equations. He...

The aim of this study is to explore the changes and coupling characteristics of carbon (C), phosphorus (P) and microbial C, P in a hillslope cropland of purple soil. The results showed that total organic carbon (TOC) ranged from 90.8 to 100.8 g . kg-1 under organic fertilizer or straw combined with inorganic fertilizer treatments (including N, NP a...

In this study, Qianyanzhou Xiangxi River Basin in the rainy season was monitored to measure different nitrogen form concentrations of rainfall and rainfall-runoff process, in order to explore the southern red soil region of nitrogen wet deposition characteristics and its influence on N output in watershed. The results showed that there were 27 time...

Forests play a vital role in global carbon (C) cycling. Accordingly, afforestation engineering programs that promote increased terrestrial C stocks are an important means to help gradually decrease atmospheric CO2 emissions. China, however, had increased its afforested area bordering hydroclimatic zones to 275.71 million hm2 between 1949 and 2010....

In this paper, we monitored different forms of nitrogen (N) transported by the subsurface flow under three different natural rainfall events and different fertilizations and conducted an associated risk evaluation on environmental health, which provides scientific basis for controlling N non-point pollution and establishing a reasonable fertilizati...

Land use changes and associative management practices can alter the biogeochemical cycling and ecological stoichiometry of carbon (C), nitrogen (N), and phosphorous (P) in ecosystems, but much remains to be clarified. This study explored the long-term effects of different land use types on C, N, and P stoichiometry and storage in a subtropical regi...

Forests play a vital role in global carbon (C) cycling. Accordingly, afforestation engineering programs that promote increased terrestrial C stocks are an important means to help gradually decrease atmospheric CO 2 emissions. China, however, had increased its afforested area bordering hydroclimatic zones to 275.71 million hm 2 between 1949 and 2010...

summary As global warming and extreme weather events increase and intensify across the globe, it becomes ever more urgent to study and understand the effects of extreme rainfall events on carbon (C), nitrogen (N), and phosphorus (P) export from terrestrial to riverine ecosystems. There is still much to learn regarding C, N, and P non-point source d...

Check-dams are the most common structures for controlling soil erosion in the Loess Plateau. However, the effect of check-dams on carbon sequestration, along with sediment transport and deposition, has not been assessed over large areas. In this study, we evaluated the carbon sequestration function of check-dams in the Loess Plateau. The results in...

It is widely accepted that excess nutrients change the dissolved inorganic carbon (DIC) system, which drives air-sea carbon dioxide (CO2) exchanges, so the changes in the DIC system will then affect the oceans’ carbon (C) biogeochemistry cycle. This study explores the impact of external nutrient input from 2006 to 2011 on the DIC system and air-sea...

Currently, water eutrophication has become a serious environmental pollution problem in China due to large amounts of nutrients input into Chinese rivers every year. In order to better understand the mechanisms of nitrogen and phosphorus transport induced by agricultural non-point pollution, we conducted simulated rainfall experiment on a hilly cro...