Yao Huang

Chinese Academy of Sciences, Peping, Beijing, China

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Publications (116)394.59 Total impact

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    ABSTRACT: Herbicides have been widely used to control weeds in croplands; however, their effects on greenhouse gas emissions remain unclear. The effects of three wheat herbicides (acetochlor, AC; tribenuron-methyl, TBM; fenoxaprop-p-ethyl, FE) and two rice herbicides (butachlor, BC; bensulfuron-methyl, BSM) on N2O and CH4 emissions were investigated in this study. In the wheat growing season, applications of AC and FE + TBM significantly reduced N2O emissions by 31% compared with no herbicide use (p = 0.001). In the rice growing season, the application of BC significantly reduced CH4 emissions by 58% (p = 0.022), and BSM significantly reduced N2O emissions by 27% (p = 0.040); however, no significant difference among treatments with regard to the aggregate emissions of N2O and CH4 in the CO2 equivalent for the 100-year horizon was observed (p > 0.05). Relative to control plots, which were not treated with herbicides, the combined application of the herbicides FE and TBM in the wheat season led to a significant decrease in greenhouse gas intensity (GHGI) by ∼41% (p = 0.002), and the application of BC together with BSM reduced GHGI by 22% in the rice season, although this reduction was not statistically significant (p = 0.158). Further investigation suggested that the inhibitory effect of herbicides on N2O emissions in the wheat field could be ascribed to low soil ammonium nitrogen and less abundance of denitrifying bacteria. The inhibitory effects of separate applications of BC on CH4 emissions in rice fields, in contrast, were linked to high soil nitrate nitrogen and urease activity.
    Atmospheric Environment 04/2015; 107. DOI:10.1016/j.atmosenv.2015.02.029 · 3.06 Impact Factor
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    ABSTRACT: Soil has been identified as a possible carbon (C) sink for sequestering atmospheric carbon dioxide (CO2). However, soil organic carbon (SOC) dynamics in agro-ecosystems is affected by complex interactions of various factors including climate, soil and agricultural management practices, which hinders our understanding of the underlying mechanisms. The objectives of this study were to use the Agricultural Production Systems sIMulator (APSIM) model to simulate the long-term SOC dynamics under different management practices at four long-term experimental sites, Zhengzhou and Xuzhou with double cropping systems and Gongzhuling and Ürümqi with single cropping systems, located in northern China. Firstly, the model was calibrated using information from the sites and literature, and its performance to predict crop growth and SOC dynamics was examined. The calibrated model was then used to assess the impacts of different management practices, including fertilizer application, irrigation, and residue retention, on C dynamics in the top 30 cm of the soil by scenario modelling. Results indicate a significant SOC sequestration potential through improved management practices of nitrogen (N) fertilizer application, stubble retention, and irrigation. Optimal N fertilization (Nopt) and 100% stubble retention (R100) increased SOC by about 11.2%, 208.29%, and 283.67% under irrigation at Gongzhuling, Zhengzhou, and Xuzhou, respectively. Soil organic carbon decreased rapidly at Ürümqi under irrigation, which was due to the enhanced decomposition by increased soil moisture. Under rainfed condition, SOC remained at a higher level. The combination of Nopt and R100 increased SOC by about 0.46% under rainfed condition at Ürümqi. Generally, agricultural soils with double cropping systems (Zhengzhou and Xuzhou) showed a greater potential to sequester C than those with single cropping systems (Gongzhuling and Ürümqi).
    Pedosphere 08/2014; 24(4):529–543. DOI:10.1016/S1002-0160(14)60039-4 · 1.38 Impact Factor
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    Yongqiang Yu, Wen Zhang, Yao Huang
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    Yongqiang Yu, Wen Zhang, Yao Huang
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    ABSTRACT: Rice is the staple food in China, and the country’s enlarging population puts increasing pressure on its rice production as well as on that of the world. In this study, we estimate the impact of climate change, CO2 fertilization, crop adaptation and the interactions of these three factors on the rice yields of China using model simulation with four hypothetical scenarios. According to the results of the model simulation, the rice yields without CO2 fertilization are predicted to decrease by 3.3 % in the 2040s. Considering a constant ricegrowing season (GS), the rice yields are predicted to increase by 3.2 %. When the effect of CO2 fertilization is integrated into the Agro-C model, the expected rice yields increase by 20.9 %. When constant GS and CO2 fertilization are both integrated into the model, the predicted rice yield increases by 28.6 %. In summary, the rice yields in China are predicted to decrease in the 2040s by 0.22 t/ha due to climate change, to increase by 0.44 t/ha due to a constant GS and to increase by 1.65 t/ha due to CO2 fertilization. The benefits of crop adaptation would completely offset the negative impact of climate change. In the future, the most of the positive effects of climate change are expected to occur in northeastern and northwestern China, and the expansion of rice cultivation in northeastern China should further enhance the stability of rice production in China.
    Climatic Change 04/2014; 124(4):763-775. DOI:10.1007/s10584-014-1129-9 · 4.62 Impact Factor
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    ABSTRACT: It is widely recognized that global warming promotes soil organic carbon (SOC) decomposition, and soils thus emit more CO2 into the atmosphere because of the warming; however, the response of SOC decomposition to this warming in different soil textures is unclear. This lack of knowledge limits our projection of SOC turnover and CO2 emission from soils after future warming. To investigate the CO2 emission from soils with different textures, we conducted a 107-day incubation experiment. The soils were sampled from temperate forest and grassland in northern China. The incubation was conducted over three short-term cycles of changing temperature from 5°C to 30°C, with an interval of 5°C. Our results indicated that CO2 emissions from sand (>50 µm), silt (2-50 µm), and clay (<2 µm) particles increased exponentially with increasing temperature. The sand fractions emitted more CO2 (CO2-C per unit fraction-C) than the silt and clay fractions in both forest and grassland soils. The temperature sensitivity of the CO2 emission from soil particles, which is expressed as Q10, decreased in the order clay>silt>sand. Our study also found that nitrogen availability in the soil facilitated the temperature dependence of SOC decomposition. A further analysis of the incubation data indicated a power-law decrease of Q10 with increasing temperature. Our results suggested that the decomposition of organic carbon in fine-textured soils that are rich in clay or silt could be more sensitive to warming than those in coarse sandy soils and that SOC might be more vulnerable in boreal and temperate regions than in subtropical and tropical regions under future warming.
    PLoS ONE 04/2014; 9(4):e95348. DOI:10.1371/journal.pone.0095348 · 3.53 Impact Factor
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    ZhangCai Qin, Yao Huang
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    ABSTRACT: Cropland soils have been shown to emit nitrous oxide (N2O) and methane (CH4) into the atmosphere and to sequester carbon when field management is improved, yet the spatiotemporal changes in the N2O and CH4 emissions and the soil organic carbon (SOC) in China's croplands are unclear with regard to an integrated global warming potential (GWP). This limits our overall evaluation of anthropogenic GHG emissions and impairs effective decision making. Based primarily on model simulations from 1980 to 2009, we estimated a 69% increase in the gross GWP of CH4 and N2O emissions, from 244 Tg CO2-eq. yr-1 in the early 1980s to 413 Tg CO2-eq. yr-1 in the late 2000s. The SOC was estimated to have increased from 54 Tg CO2-eq. yr-1 to 117 Tg CO2-eq. yr-1 during the same period. A reduction in the carbon input during the rice season, along with an improvement of synthetic nitrogen use efficiency in crops to 40%, would mitigate GHG emissions by 111 Tg CO2-eq. yr-1 and keep SOC sequestration at 82 Tg CO2 yr-1. Together, this would amount to a reduction of 193 Tg CO2-eq. yr-1, representing ~47% of the gross GWP in the late 2000s. The mitigation of GHG emissions in Henan, Shandong, Hunan, Jiangsu, Hubei, Sichuan, Anhui, Jiangxi, Guangdong and Hebei Provinces could lead to a ~66% national improvement and should be given priority.
    Environmental Science & Technology 02/2014; 48(5). DOI:10.1021/es404352h · 5.48 Impact Factor
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    ABSTRACT: Rice paddies are a major anthropogenic source of the atmospheric methane. However, because of the high spatial heterogeneity, making accurate estimations of the methane emission from rice paddies is still a big challenge, even with complicated models. Data scarcity is one of the substantial causes of the uncertainties in estimating the methane emissions on regional scales. In the present study, we discussed how data scarcity affected the uncertainties in model estimations of rice paddy methane emissions, from county/provincial scale up to national scale. The uncertainties in methane emissions from the rice paddies of China was calculated with a local-scale model and the Monte Carlo simulation. The data scarcities in five of the most sensitive model variables, field irrigation, organic matter application, soil properties, rice variety and production were included in the analysis. The result showed that in each individual county, the within-cell standard deviation of methane flux, as calculated via Monte Carlo methods, was 13.5–89.3% of the statistical mean. After spatial aggregation, the national total methane emissions were estimated at 6.44–7.32 Tg, depending on the base scale of the modeling and the reliability of the input data. And with the given data availability, the overall aggregated standard deviation was 16.3% of the total emissions, ranging from 18.3–28.0% for early, late and middle rice ecosystems. The 95% confidence interval of the estimation was 4.5–8.7 Tg by assuming a gamma distribution. Improving the data availability of the model input variables is expected to reduce the uncertainties significantly, especially of those factors with high model sensitivities.
    Geoscientific Model Development 01/2014; 7:1211-1224. DOI:10.5194/gmd-7-1211-2014 · 6.09 Impact Factor
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    ABSTRACT: Improving management of soil organic carbon (SOC) has been considered as a substantial mitigation strategy to climate change. Management such as stubble retention (SR), conservation tillage (ZT), and fertilization are recommended for both promoting production and accumulating SOC. However, whether such management practices can cause net increase in SOC or just a slow-down of SOC decline largely depends on the current status of SOC for a given region. This paper synthesized the available SOC data in the croplands of China, and analysed the change of SOC in the top 20 cm soil as a result of management change. The results showed that, on average, SOC increased by 18.3% through SR, by 9.1% through ZT, and by 12.4%, 36.9% and 41.5% through application of inorganic (IF), organic (OF) and combined inorganic and organic fertilizers (IOF), respectively, compared to those under stubble removal, conventional tillage and no fertilization. Under SR, ZT, IF, OF and IOF, SOC increased by 16.0%, 10.2%, 8.2%, 32.2% and 41.3%, respectively, at the end of the trials compared with the initial values at the start of the trials. Our analysis also showed that in Northeast and Northwest China, SOC in agricultural soils is still decreasing due to cultivation. In North and South China, however, SOC appears to have reached a new equilibrium of low SOC state after a long cultivation history, and soils have greater potential to sequester C. Our analysis highlights the need of taking account of the baseline status to assess the net soil C balance over time and space.
    Pedosphere 12/2013; 23(6):717–728. DOI:10.1016/S1002-0160(13)60064-8 · 1.38 Impact Factor
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    ABSTRACT: Soil respiration (R s) is one of the key processes that underline our understanding of carbon cycle in terrestrial ecosystems. Great uncertainty remains in the previous global R s estimates with a difference of 70 Pg C a−1 between the highest and lowest estimates. Thus, the present study aimed to estimate the global annual R s and investigate the interannual and spatial variability in global annual R s using a semi-mechanistic, empirically-based model which included climatic factors (temperature and precipitation) and topsoil (0–20 cm) organic carbon storage. About 657 published studies of annual R s from 147 measurement sites were included in this meta-analysis. The global data sets from 1970 to 2008 on climate, surface air temperature, and soil properties were collected. The Monte Carlo method was used to propagate the simulation errors to global R s. The results indicated that the mean annual global R s was 94.4 Pg C a−1, increasing at roughly 0.04 Pg C a−1 (∼0.04% a−1) from 1970 to 2008. The R s rate increased from colder, drier and less soil carbon-rich regions to warmer, moister and more carbon-rich regions. Highest R s rates appeared in the tropical forest, while the lowest ones were in polar and desert regions. The annual R s correlated directly with global temperature anomalies, suggesting that the interannual variability in temperature was responsible for the interannual variations in predicted global R s. The global R s increased from high-latitude zones to low-latitude zones. Further studies are recommended to explore the relationship between soil respiration and vegetation characters.
    Chinese Science Bulletin 11/2013; 58(33). DOI:10.1007/s11434-013-5912-1 · 1.37 Impact Factor
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    Yongqiang Yu, Yao Huang, Wen Zhang
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    ABSTRACT: Projected changes in soil organic carbon stocks of China's croplands under different agricultural managements, 2011–2050 a b s t r a c t The timing, magnitude, and regional distribution of soil organic carbon (SOC) changes are uncertain when factoring in climate change and agricultural management practices. The goal of this study is to analyze the implications of changes in climate and agricultural management for Chinese soil carbon sequestration over the next 40 years. We used the Agro-C model to simulate climate and agricultural management scenarios to investigate the combined impacts of climate change and management on future SOC stocks in China's croplands. The model was run for croplands on mineral soils in China, which make up a total of 130 M ha of cropland. The model used climate data (years 2011–2050) from the FGOALS and PRECIS climate models based on four Intergovernmental Panel on Climate Change (IPCC) emissions scenarios. Three equidistant agricultural management scenarios were used. S0 was a current scenario, and S2 was an optimal scenario. Under the S2 scenario, crop yields increased annually by 1%, the proportion of crop residue retained in the field reached 90% by 2050, and the area of no-tillage increased to 50% of the cultivated area by 2050. The S1 scenario applied half of the increased rates in crop yields, residue retention and no-tillage area values that were used in the S2 scenario. Across all croplands in China, the results suggest that SOC will increase under all combinations of climate and management and that the effect of climate change is much smaller than the effect of changes in agricultural management. Most croplands in China show a significant increase in SOC stocks, while very few zones (mainly in northeastern China) show a decrease. Rice paddy soils under the intensive farming management scenario show higher rates of carbon sequestration than dry-land soils. The maximum carbon sequestration potential of the croplands of China is estimated to be 2.39 Pg C under S2. Annual increases in SOC stocks could offset a maximum of 2.9% of the CO 2 emissions from fossil-fuel combustion in 2009. These results suggest that China's croplands, especially rice paddies, may play an important role in C sequestration and future climate change mitigation.
    Agriculture Ecosystems & Environment 09/2013; 178:109-120. DOI:10.1016/j.agee.2013.06.008 · 3.20 Impact Factor
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    ABSTRACT: [1] Soil organic carbon (SOC) in cropland is of great importance to the global carbon (C) balance and to agricultural productivity, but it is highly sensitive to human activities such as irrigation and crop rotation. It has been observed that under certain improved management practices, cropland soils can sequestrate additional C beyond their existing SOC level before reaching the C saturation state. Here we use data from worldwide, long-term agricultural experiments to develop two statistical models to determine the saturated SOC level (SOCS) in upland and paddy agroecosystems, respectively. We then use the models to estimate SOC sequestration potential (SOCP) in Chinese croplands. SOCP is the difference between SOCS and existing SOC level (SOCE). We find that the models for both the upland and paddy agroecosystems can reproduce the observed SOCS data from long-term experiments. The SOCE and SOCS stock in Chinese upland and paddy croplands (0–30 cm soil) are estimated to be 5.2 and 7.9 Pg C with national average densities of 37.4 and 56.8 Mg C ha−1, respectively. As a result, the total SOC sequestration potential is estimated to be 2.7 Pg C or 19.4 Mg C ha−1 in Chinese cropland. Paddy has a relatively higher SOCE (45.4 Mg C ha−1) than upland (34.7 Mg C ha−1) and also a greater SOCP at 26.1 Mg C ha−1 compared with 17.2 Mg C ha−1 in the upland. The SOC varies dramatically among different regions. Northeast China has the highest SOCE and SOCS density, while the Loess Plateau has the greatest SOCP density. The time required to reach SOC saturation in Chinese cropland is highly dependent on management practices applied. Chinese cropland has relatively low SOC density in comparison to the global average but could have great potentials for C sequestration under improved agricultural management strategies.
    Global Biogeochemical Cycles 09/2013; 27(3):711-722. DOI:10.1002/gbc.20068 · 4.53 Impact Factor
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    ABSTRACT: Crop models often simulate drought impacts with full and no irrigation scenarios, while planners are more interested in whether the current available irrigation water can cope with the future more serious droughts. This paper addresses a key constraint common to modeling studies: the limited representation of actual irrigation water supply. We present a data-driven approach to identify a benchmark for agronomic drought risk levels as defined by water availability thresholds at the baseline climate (1980-2008) using reported crop yields, climate and irrigation statistics. Then, holding the current irrigation supplies, we adopted Bayesian formula to estimate magnitude of the future water availability and the associated probability of crops yields being decreased to rainfall-deficiency under climate conditions in 2030s (2020-2040) based on the RegCM3 climate model output driven by IPCC SRES A1B scenario. Results reveal that future drought stress would overwhelm the irrigation capacity of current supplies in northern and western China, while drought remains at baseline climate levels in the central, eastern and southern regions. The largest increases in the probability of projected drought risk were in northeast and southwest, ranging from 14% to 28% above baseline climate. Regional drought impacts for grain self sufficiency are discussed. (c) 2012 Elsevier B.V. All rights reserved.
    Agricultural and Forest Meteorology 09/2013; 178-179:56-65. DOI:10.1016/j.agrformet.2012.06.002 · 3.89 Impact Factor
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    ABSTRACT: Soil organic carbon (SOC) dynamics in Australian wheat-growing areas were simulated from 1960 to 2010 using Agro-C, a calibrated and validated biogeophysical model. Previously published data from field measurements were used to parameterize the Agro-C model. Model simulations show a decreasing trend in SOC over the last 50 years, mainly attributable to relatively low organic carbon (C) inputs. The rate of decrease in SOC tended to slow in the last two decades due primarily to an increase in wheat yields, which resulted in an increase in C input. Overall, we estimate that Australian wheat-growing areas, covering an area of 15.09 million hectares (Mha), lost 156 (86-222, 95% confidence interval) Tg C in the topsoil (to 30 cm depth) from 1960 to 2010. Approximately 80% of the SOC loss occurred in the period between the 1960s and the 1980s. Spatially, the SOC loss in areas with relatively high temperature and low precipitation, such as Queensland, the northern part of New South Wales and Western Australia, was more significant than that in other areas. We suggest that the loss of SOC could be halted, or even reversed, with an additional input of organic C into the soil at a minimum rate of 0.4 Mg ha(-1) yr(-1).
    PLoS ONE 05/2013; 8(5):e63324. DOI:10.1371/journal.pone.0063324 · 3.53 Impact Factor
  • Tianyi Zhang, Yao Huang
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    ABSTRACT: This study estimated the past warming impacts on wheat and maize from 1980 to 2008 based on data from 2339 counties in China, providing a finer portrait of climatic effects than earlier assessments that often focused on a provincial scale. We detected an overall negative effect of the average temperature (Tavg) and diurnal temperature range (DTR) on wheat and maize yields on a national level, but our results also indicate notable beneficial effects of the Tavg in the northcentral region for wheat and the eastern parts of northeast for maize that, in most previous studies, were overlooked due to the coarseness of provincial data. Because wheat cultivation is highly intense in the north, the positive Tavg effect in the region has offset losses from warming in other areas, improving national production by up to 1.6% relative to the average level over the study period. For maize, unfortunately, approximately 5.8% production was lost due to increases in the Tavg as the dominant adverse effect. Given the reduced DTR in the major producing regions, the past trends of the DTR have boosted wheat production by up to 2.1% and maize by up to 1.4%. As a result, the combined effects of the Tavg and DTR have increased wheat production by up to 3.7%, but decreased maize production by 4.4%, equivalent to approximately 10% of the actual change in Chinese wheat and maize production from 1980 to 2008. Copyright © 2012 Royal Meteorological Society
    International Journal of Climatology 03/2013; 33(3):699-708. DOI:10.1002/joc.3463 · 3.40 Impact Factor
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    ABSTRACT: An extensive dataset on rice phenology in China, including 202 series broadly covering the past three decades (1980s-2000s), was compiled. From these data, we estimated the responses of growth duration length to temperature using a regression model based on the data with and without detrending. Regression coefficients derived from the detrended data reflect only the temperature effect, whereas those derived from data without detrending represent a combined effect of temperature and confounding cultivar shifts. Results indicate that the regression coefficients calculated from the data with and without detrending show an average shortening of the growth duration of 4.1-4.4 days for each additional increase in temperature over the full growth cycle. Using the detrended data, 95.0% of the data series exhibited a negative correlation between the growth duration length and temperature; this correlation was significant in 61.9% of all of the data series. We then compared the difference between the two regression coefficients calculated from data with and without detrending and found a significantly greater temperature sensitivity using the data without detrending (-2.9 days °C(-1) ) than that derived from the detrended data (-2.0 days °C(-1) ) in the period of emergence to heading for the late rice, producing a negative difference in temperature sensitivity (-0.9 days °C(-1) ). This implies that short-duration cultivars were planted with increase in temperature and exacerbated the undesired phenological change. In contrast, positive differences were detected for the single (0.6 days °C(-1) ) and early rice (0.5 days °C(-1) ) over the full growth cycle, which might indicate that long-duration cultivars were favoured with climate warming, but these differences were insignificant. In summary, our results suggest that a major, temperature induced change in the rice growth duration is underway in China and that using a short-duration cultivar has been accelerating the process for late rice.
    Global Change Biology 02/2013; 19(2):563-70. DOI:10.1111/gcb.12057 · 8.22 Impact Factor
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    ABSTRACT: Mean residence time (MRT) of topsoil organic carbon is one critical parameter for predicting future land carbon sink dynamics. Large uncertainties remain about controls on the variability in global MRT of soil organic carbon. We estimated global MRT of topsoil (0-20 cm) organic carbon in terrestrial ecosystems and found that mean annual air temperature, annual precipitation, and topsoil nitrogen storage were responsible for the variability in MRT. An empirical climate and soil nitrogen - based (Clim&SN) model could be used to explain the temporal and spatial variability in MRT across various ecosystems. Estimated MRT was lowest in the low-latitude zones, and increased toward high-latitude zones. Global MRT of topsoil organic carbon showed a significant declining tendency between 1960 and 2008, particularly in the high-latitude zone of the northern hemisphere. The largest absolute and relative changes (0.2% per yr) in MRT of topsoil organic carbon from 1960 to 2008 occurred in high-latitude regions, consistent with large carbon stocks in, and greater degree of climate change being experienced by, these areas. Overall, global MRT anomalies (differences between MRT in each year and averaged value of MRT from 1960 to 2008) of terrestrial topsoil organic carbon were decreasing from 1960 to 2008. Global MRT anomalies decreased significantly (P<0.001) with the increase of global temperature anomalies, indicating that global warming resulted in faster turnover rates of topsoil organic carbon.
    Global and Planetary Change 01/2013; 100(1):99-108. DOI:10.1016/j.gloplacha.2012.10.006 · 3.71 Impact Factor
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    ABSTRACT: Soil respiration is an important process in terrestrial carbon cycle. Concerning terrestrial ecosystems in China, quantifying the spatiotemporal pattern of soil respiration at the regional scale is critical in providing a theoretical basis for evaluating carbon budget. In this study, we used an empirically based, semi-mechanistic model including climate and soil properties to estimate annual soil respiration from terrestrial ecosystems in China from 1970 to 2009. We further analyzed the relationship between interannual variability in soil respiration and climatic factors (air temperature and precipitation). Results indicated that the distribution of annual soil respiration showed clear spatial patterns. The highest and lowest annual soil respiration rates appeared in southeastern China and northwestern China, respectively, which was in accordance with the spatial patterns of mean annual air temperature and annual precipitation. Although the mean annual air temperature in northwestern China was higher than that in some regions of northeastern china, a greater topsoil organic carbon storage in northeastern China might result in the higher annual soil respiration in this region. By contrast, lower temperature, less precipitation and smaller topsoil organic carbon pool incurred the lowest annual soil respiration in northwestern China. Annual soil respiration from terrestrial ecosystems in China varied from 4.58 to 5.19 Pg C•yr-1 between 1970 and 2009. During this time period, on average, annual soil respiration was estimated to be 4.83 Pg C•yr-1. Annual soil respiration in China accounted for 4.93%-6.01% of the global annual soil CO2 emission. The interannual variability in soil respiration depended on the interannual variability in precipitation and mean air temperature. In order to reduce the uncertainty in estimating annual soil respiration at regional scale, more in situ measurements of soil respiration and relevant factors (e.g. climate, soil and vegetation) should be made simultaneously and historical soil property data sets should also be established.
    Science China Earth Science 12/2012; DOI:10.1007/s11430-012-4464-6 · 1.34 Impact Factor
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    Yongqiang Yu, Yao Huang, Wen Zhang
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    ABSTRACT: In this study, we investigated how climate, crop management and variety renewal have interactively affected the rice yields in China for the past three decades. Using the Agro-C model and census yields, the parameters of the photosynthetic ability during the past three decades in the various Agro-ecological Zones were estimated. The Agro-C model, which uses grid-based datasets of climate, crop management and variety renewal, was used to simulate the change in rice yield under various explorative scenarios. Based on these results, we deduced the relative contribution of various factors to the rice yield. The annual increase in rice yields due to genetic improvement in the various AEZs was 0.31–1.63% for single rice, 0.29–1.34% for early rice and 0.07–1.70% for late rice. The rice yield over the past three decades, including all cultivated types, achieved a 79 kg ha−1 or a 1.8% increase per year. The increase in rice yield over the past three decades is comprised of increases that can be attributed to climate (4.4%), management (9.3%) and variety (38.9%). Genetic improvement is the decisive factor and contributed to 74.0% of the total increase in yield.
    Field Crops Research 09/2012; 136:65-75. DOI:10.1016/j.fcr.2012.07.021 · 2.61 Impact Factor

Publication Stats

3k Citations
394.59 Total Impact Points

Institutions

  • 2001–2015
    • Chinese Academy of Sciences
      • • Institute of Botany
      • • State Key Laboratory of Vegetation and Environmental Change
      • • Institute of Atmospheric Physics
      Peping, Beijing, China
  • 2004–2013
    • Technical Institute of Physics and Chemistry
      Peping, Beijing, China
    • Institute of Atmospheric Physics
      北江, Zhejiang Sheng, China
  • 2002–2011
    • Nanjing Agricultural University
      • College of Resources and Environmental Sciences
      Nanjing, Jiangsu Sheng, China
  • 2008
    • Inner Mongolia University
      Suiyüan, Inner Mongolia, China
  • 2007
    • Nanjing University of Information Science & Technology
      Nan-ching, Jiangsu Sheng, China
  • 2005
    • Inner Mongolian Normal University
      Suiyüan, Inner Mongolia, China
  • 1997–2003
    • Rice University
      • Department of Ecology and Evolutionary Biology
      Houston, Texas, United States