Loading...

Archive

    For Selected: Toggle Thumbnails
    Special Issue: Systematic Synthesis of Impacts of Climate Change on China’s Crop Production System
    Editorial - Systematic Synthesis of Impacts of Climate Change on China’s Crop Production System
    TANG Hua-jun, WU Wen-bin, YANG Peng , LI Zheng-guo
    2014, 13(7): 1413-1417.  DOI: 10.1016/S2095-3119(14)60801-7
    Abstract ( )   PDF in ScienceDirect  
    Managing Climate Change Risk in China’s Agricultural Sector: The Potential for an Integrated Risk Management Framework
    Kevin Z. Chen , Claire Hsu
    2014, 13(7): 1418-1431.  DOI: 10.1016/S2095-3119(14)60820-0
    Abstract ( )   PDF in ScienceDirect  
    Climate change poses a serious threat to the future food security of China, which is among the most disaster-prone countries in the world. This paper discusses the implications of climate change for China’s agricultural sector. Its main objectives are to identify the agricultural risks associated with climate change, to introduce a conceptual framework for agricultural climate risk management and to enumerate key adaptation strategies, challenges, and recommendations.
    How Could Agricultural Land Systems Contribute to Raise Food Production Under Global Change?
    WU Wen-bin, YU Qiang-yi, Verburg H Peter, YOU Liang-zhi, YANG Peng , TANG Hua-jun
    2014, 13(7): 1432-1442.  DOI: 10.1016/S2095-3119(14)60819-4
    Abstract ( )   PDF in ScienceDirect  
    To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequences require sustainable agricultural land use practices as supplementary to advanced biotechnology and agronomy. This review paper, from a land system perspective, systematically proposed and analyzed three interactive strategies that could possibly raise future food production under global change. By reviewing the current literatures, we suggest that cropland expansion is less possible amid fierce land competition, and it is likely to do less in increasing food production. Moreover, properly allocating crops in space and time is a practical way to ensure food production. Climate change, dietary shifts, and other socio-economic drivers, which would shape the demand and supply side of food systems, should be taken into consideration during the decision-making on rational land management in respect of sustainable crop choice and allocation. And finally, crop-specific agricultural intensification would play a bigger role in raising future food production either by increasing the yield per unit area of individual crops or by increasing the number of crops sown on a particular area of land. Yet, only when it is done sustainably is this a much more effective strategy to maximize food production by closing yield and harvest gaps.
    Framework of SAGI Agriculture Remote Sensing and Its Perspectives in Supporting National Food Security
    SHI Yun, JI Shun-ping, SHAO Xiao-wei, TANG Hua-jun, WU Wen-bin, YANG Peng, ZHANG , Yong-jun , Shibasaki Ryosuke
    2014, 13(7): 1443-1450.  DOI: 10.1016/S2095-3119(14)60818-2
    Abstract ( )   PDF in ScienceDirect  
    Remote sensing, in particular satellite imagery, has been widely used to map cropland, analyze cropping systems, monitor crop changes, and estimate yield and production. However, although satellite imagery is useful within large scale agriculture applications (such as on a national or provincial scale), it may not supply sufficient information with adequate resolution, accurate geo-referencing, and specialized biological parameters for use in relation to the rapid developments being made in modern agriculture. Information that is more sophisticated and accurate is required to support reliable decision-making, thereby guaranteeing agricultural sustainability and national food security. To achieve this, strong integration of information is needed from multi-sources, multi-sensors, and multi-scales. In this paper, we propose a new framework of satellite, aerial, and groundintegrated (SAGI) agricultural remote sensing for use in comprehensive agricultural monitoring, modeling, and management. The prototypes of SAGI agriculture remote sensing are first described, followed by a discussion of the key techniques used in joint data processing, image sequence registration and data assimilation. Finally, the possible applications of the SAGI system in supporting national food security are discussed.
    Observed Climatic Variations in the Growing Season of Field Crops in Northeast China from 1992 to 2012
    LIU Yang, JIANG Wen-lai, XIAO Bi-lin, LEI Bo
    2014, 13(7): 1451-1461.  DOI: 10.1016/S2095-3119(14)60812-1
    Abstract ( )   PDF in ScienceDirect  
    To determine the potential effects of climate change on crop phenological development and productivity, an integrated analysis was conducted based on the observed climatic and phenological records of Northeast China from 1992 to 2012. A set of quality assurance procedures, including repeated record checks, agro-meteorological station selection, internal consistency checks, temporal outlier checks, spatial outlier checks, and interpolation of missing data, were designed and applied to the phenology datasets of spring maize and paddy rice. Our results indicated that almost all phenological dates of spring maize and paddy rice became increasingly delayed from 1992 to 2012. The duration of the growing season was prolonged, particularly for the grain-filling stage (GS3). The prolonged growing season was beneficial to productivity. For spring maize, the average precipitation during GS3 decreased at a rate of 27.46 mm/decade, and the annual accumulated temperature over 10°C increased at a rate of 31.07°C/ decade. Farmers initiatively adjusted crop cultivars and selected drought-resistant crops to cope with the challenges of drought.
    HapIII of TaSAP1-A1, a Positively Selected Haplotype in Wheat Breeding
    CHANG Jian-zhong, HAO Chen-yang, CHANG Xiao-ping, ZHANG Xue-yong , JING Rui-lian
    2014, 13(7): 1462-1468.  DOI: 10.1016/S2095-3119(14)60808-X
    Abstract ( )   PDF in ScienceDirect  
    Stress-associated protein (SAP) has functions in maintaining plant cell elongation, embryo development and response to abiotic stresses. TaSAP1-A1, one of the Triticum aestivum SAP1 (TaSAP1) members located on wheat chromosome 7A was isolated for polymorphism analysis. HapIII of TaSAP1-A1 was found significantly associated with thousand-grain weight (TGW) in multiple environments. In this study, HapIII also made a positive contribution to TGW in Population 2. The distribution of TaSAP1-A1 HapIII was tracked among varieties released in different years and geographical environments of China. The frequency of HapIII showed an increasing trend during the breeding process in two different populations. The HapIII was gradually selected and applied from 6.36% in landraces to 13.50% in modern varieties. These results exhibited that TaSAP1-A1 HapIII was positively selected during wheat breeding, which is beneficial for grain-yield improvement. The preferred HapIII was initially selected and applied in the higher latitude areas of China in accord with the long day season and longer grain filling stage in these areas. Moreover, the frequency of HapIII in recent modern varieties was still quite low (19.29-26.67%). It indicated a high application potential of TaSAP1-A1 HapIII for improving grain yield in wheat breeding.
    Allelic Variation in Loci for Adaptive Response and Its Effect on Agronomical Traits in Chinese Wheat (Triticum aestivum L.)
    GAO Li-feng, LIU Pan, GU Yan-chun , JIA Ji-zeng
    2014, 13(7): 1469-1476.  DOI: 10.1016/S2095-3119(14)60814-5
    Abstract ( )   PDF in ScienceDirect  
    Heading date was an important trait that decided the adaptation of wheat to environments. It was modified by genes involved in vernalization response, photoperiod response and development rate. In this study, four loci Xgwm261, Xgwm219, Xbarc23 and Ppd-D1 which were previously reported related to heading time were analyzed based on three groups of wheat including landraces (L), varieties bred before 1983 (B82) and after 1983 (A83) collected from Chinese wheat growing areas. Generally, heading date of landrace was longer than that of varieties. Significant differences in the heading time existed within the groups, which implied that diversification selection was much helpful for adaptation in each wheat zone. Photoperiod insensitive allele Ppd-D1a was the first choice for both landrace and modern varieties, which promoted the heading date about four days earlier than that of sensitive allele Ppd-D1b. The three SSR loci had different characters in the three groups. Predominant allele combination for each zone was predicted for wheat group L and A83, which made great contribution to advantageous traits. Xgwm219 was found to be significantly associated with heading date in Yellow and Huai River Winter Wheat Zone (Zone II) and spike length in Middle and lower Yangtze Valley Winter Wheat Zone (Zone III), which implied functional diversification for adaption. Variation for earliness genes provided here will be helpful for whet breeding in future climatic change.
     Impacts of Nighttime Warming on the Soil Nematode Community in a Winter Wheat Field of Yangtze Delta Plain, China
    SONG Zhen-wei, ZHANG Bin, TIAN Yun-lu, DENG Ai-xing, ZHENG Cheng-yan, Md Nurul Islam, Md Abdul Mannaf , ZHANG Wei-jian
    2014, 13(7): 1477-1485.  DOI: 10.1016/S2095-3119(14)60807-8
    Abstract ( )   PDF in ScienceDirect  
    Changes in the soil nematode community induced by global warming may have a considerable influence on agro-ecosystem functioning. However, the impacts of predicted warming on nematode community in farmland (e.g., winter wheat field) have not been well documented. Therefore, a field experiment with free air temperature increase (FATI) was conducted to investigate the responses of the soil nematode community to nighttime warming in a winter wheat field of Yangtze Delta Plain, China, during 2007 to 2009. Nighttime warming (NW) by 1.8°C at 5-cm soil depth had no significant impact on the total nematode abundance compared to un-warmed control (CK). However, NW significantly affected the nematode community structure. Warming favored the bacterivores and fungivores, such as Acrobeles, Monhystera, Rhabditis, and Rhabdontolaimus in bacterivores, and Filenchus in fungivores, while the plant-parasites were hindered, such as Helicotylenchus and Psilenchus. Interestingly, the carnivores/ omnivores remained almost unchanged. Hence, the abundances of bacterivores and fungivores were significantly higher under NW than those under CK. Similarly, the abundances of plant-parasites were significantly lower under NW than under CK. Furthermore, Wasilewska index of the nematode community was significantly higher under NW than those under CK, indicating beneficial effect to the plant in the soil. Our results suggest that nighttime warming may improve soil fertility and decrease soil- borne diseases in winter wheat field through affecting the soil nematode community. It is also indicated that nighttime warming may promote the sustainability of the nematode community by altering genera-specific habitat suitability for soil biota.
    Influence of Climate and Socio-Economic Factors on the Spatio-Temporal Variability of Soil Organic Matter: A Case Study of Central Heilongjiang Province, China
    SHI Shu-qin, CAO Qi-wen, YAO Yan-min, TANG Hua-jun, YANG Peng, WU Wen-bin, XU Heng-zhou, LIU Jia , LI Zheng-guo
    2014, 13(7): 1486-1500.  DOI: 10.1016/S2095-3119(14)60815-7
    Abstract ( )   PDF in ScienceDirect  
    For the scientific management of farmland, it is significant to understand the spatio-temporal variability of soil organic matter and to study the influences of related factors. Using geostatistical theory, GIS spatial analysis, trend analysis and a Geographically Weighted Regression (GWR) model, this study analyzed the response of soil organic matter to climate and socio-economic factors in central Heilongjiang Province during the past 25 years. Second soil survey data of China for 1979-1985, 2005 field sampling data, climate observations and socio-economic data for 1980-2005 were analyzed. First, soil organic matter in 2005 was spatially interpolated using the Co-Kriging method along with auxiliary data sets of soil type and pH. The spatio-temporal variability was then studied by comparison with the 1980s second soil census data. Next, the temporal trends in climate and socio-economic factors over the past 25 years were investigated. Finally, we examined the variation of the response of soil organic matter to climate and socio-economic factors using the GWR model spatially and temporally. The model showed that 53.82% area of the organic matter content remained constant and 29.39% has decreased during the past 25 years. The impact of precipitation on organic matter content is mainly negative, with increasing absolute values of the regression coefficient. The absolute value of regression coefficient of annual average temperature has decreased, and more areas are now under its negative effects. In addition, the areas of positive regression coefficient of annual sunshine hours have northward shifted, with the increasing absolute value of positive coefficient and decreasing absolute value of negative coefficient. The areas of positive regression coefficient of mechanized farming as a socio-economic factor have westward shifted, with the increasing absolute value of negative coefficient and decreasing absolute value of positive coefficient. The area of regions with the positive regression coefficient of irrigation has expanded. The regions with positive regression coefficient of fertilizer use have shrinked. The positive regression coefficient of mulch film consumption has significantly increased. The regression coefficient of pesticide consumption was mainly positive in the west of the study area, while it was negative to the east. Generally, GWR model is capable to investigate the influence of both climatic and socio-economic factors, avoided the insufficiency of other research based on the single perspective of climatic or socio-economic factors. Therefore, we can conclude that GWR model could provide methodological support for global change research and serve as basic reference for cultivated land quality improvement and agricultural decision making.
    Drought Change Trend Using MODIS TVDI and Its Relationship with Climate Factors in China from 2001 to 2010
    LIANG Liang, ZHAO Shu-he, QIN Zhi-hao, HE Ke-xun, CHEN Chong, LUO Yun-xiao
    2014, 13(7): 1501-1508.  DOI: 10.1016/S2095-3119(14)60813-3
    Abstract ( )   PDF in ScienceDirect  
    Changes in drought trends and its relationship with climate change in China were examined in this study. The temperature vegetation drought index (TVDI) datasets recorded during 2001 to 2010 in China were constructed by using the moderateresolution imaging spectroradiometer (MODIS) data, and the temporal and spatial variations in drought were analyzed. In addition, the mean temperature, mean precipitation, mean relative humidity, and mean sunshine duration data collected from 557 local weather stations in China were analyzed. The relationships between drought and these climate factors were also analyzed by using correlation analysis and partial correlation analysis. Changes in drought tendency were shown to differ among four regions throughout the country. The fluctuations in climate in the regions of northeastern China, Qinling-Huaihe, and central Qinghai were caused by the increase in soil moisture, and that in southern Tibet was caused by the intensification of drought. Meteorological factors exhibited varied effects on drought among the regions. In southern China, the main influential factor was temperature; other factors only showed minimal effects. That in the northern and northwestern regions was sunshine duration, and those in the Qinghai-Tibet Plateau were relative humidity and temperature.
    Contribution of Drought to Potential Crop Yield Reduction in a Wheat-Maize Rotation Region in the North China Plain
    HU Ya-nan, LIU Ying-jie, TANG Hua-jun, XU Yin-long , PAN Jie
    2014, 13(7): 1509-1519.  DOI: 10.1016/S2095-3119(14)60810-8
    Abstract ( )   PDF in ScienceDirect  
    With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and maize yield and their changes at a 0.5°×0.5° grid scale in the wheat-maize rotation planting area in the North China Plain under the A1B climate change scenario using the Decision Support System for Agrotechnology Transfer (DSSAT) model and the outputs of the regional climate modeling system - Providing Regional Climates for Impacts Studies (PRECIS). Self-calibrating palmer drought severity index was used as drought recognition indicator. Two time slices used for the study were the baseline (1961-1990) and 40 years of 2011-2050. The results indicate that the potential planting region for double crop system of wheat-maize would expend northward. The statistic conclusions of crop simulations varied considerably between wheat and maize. In disaster-affected seasons, wheat yield would increase in the future compared with baseline yields, whereas in opposite for maize yield. Potential crop yield reductions caused by drought would be lower for wheat and higher for maize, with a similar trend found for the ratio of potential crop yield reductions for both crops. It appears that the negative impact of drought on maize was larger than that on wheat under climate change A1B scenario.
    Interactive Effects of Elevated CO2 and Temperature on Rice Planthopper, Nilaparvata lugens
    SHI Bao-kun, HUANG Jian-li, HU Chao-xing , HOU Mao-lin
    2014, 13(7): 1520-1529.  DOI: 10.1016/S2095-3119(14)60804-2
    Abstract ( )   PDF in ScienceDirect  
    It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6°C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3°C temperature increase on a complete generation of the brown planthopper (Nilaparvata lugens) on rice (Oryza sativa). Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper (BPH) nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a significant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.
    Effects of Powdery Mildew on 1000-Kernel Weight, Crude Protein Content and Yield of Winter Wheat in Three Consecutive Growing Seasons
    CAO Xue-ren, YAO Dong-ming, DUAN Xia-yu, LIU Wei, FAN Jie-ru, DING Ke-jian, ZHOU Yi-lin
    2014, 13(7): 1530-1537.  DOI: 10.1016/S2095-3119(14)60806-6
    Abstract ( )   PDF in ScienceDirect  
    In order to clarify the impact posed by wheat powdery mildew (Blumeria graminis f. sp. tritici) on the yield and yield components in different epidemic seasons, field trials were conducted in three growing seasons, 2009-2010, 2010-2011 and 2011-2012, in Langfang City, Hebei Province, China. The relationships between 1000-kernel weight, crude protein content of grain and yield and disease index (DI), as well as area under disease progress curve (AUDPC) were studied. The models of the percentage of loss of 1000-kernel weight, crude protein content and yield were constructed using DI at critical point (CP) of growth stages (GS) and AUDPC in the three growing seasons, respectively. The CPs for estimating 1 000-kernel weight, crude protein content of grain and yield of wheat caused by powdery mildew were GS 11.1, GS 10.5.3 and GS 10.5.3, respectively. Models based on DI at CP to estimate the percentage of loss of 1 000-kernel weight, crude protein content of grain and yield were better than models based on AUDPC. And models of the percentage of loss of 1 000-kernel weight, crude protein content and yield for 2011-2012 season were significant different from these for 2009-2010 and 2010-2011 seasons. These results indicated that besides powdery mildew, weather conditions also had influence on 1 000-kernel weight, crude protein content of grain and yield loss of wheat when powdery mildew occurred.
    Corn Yield Forecasting in Northeast China Using Remotely Sensed Spectral Indices and Crop Phenology Metrics
    WANG Meng, TAO Fu-lu , SHI Wen-jiao
    2014, 13(7): 1538-1545.  DOI: 10.1016/S2095-3119(14)60817-0
    Abstract ( )   PDF in ScienceDirect  
    Early crop yield forecasting is important for food safety as well as large-scale food related planning. The phenology-adjusted spectral indices derived from Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to develop liner regression models with the county-level corn yield data in Northeast China. We also compared the different spectral indices in predicting yield. The results showed that, using Enhanced Vegetation Index (EVI), Normalized Difference Water Index (NDWI) and Land Surface Water Index (LSWI), the best time to predict corn yields was 55-60 days after green-up date. LSWI showed the strongest correlation (R2=0.568), followed by EVI (R2=0.497) and NDWI (R2=0.495). The peak correlation between Wide Dynamic Range Vegetation Index (WDRVI) and yield was detected 85 days after green-up date (R2=0.506). The correlation was generally low for Normalized Difference Vegetation Index (NDVI) (R2=0.385) and no obvious peak correlation existed for NDVI. The coefficients of determination of the different spectral indices varied from year to year, which were greater in 2001 and 2004 than in other years. Leave-one-year-out approach was used to test the performance of the model. Normalized root mean square error (NRMSE) ranged from 7.3 to 16.9% for different spectral indices. Overall, our results showed that crop phenology-tuned spectral indices were feasible and helpful for regional corn yield forecasting.
    The Effects of Climate Change on the Planting Boundary and Potential Yield for Different Rice Cropping Systems in Southern China
    YE Qing, YANG Xiao-guang, LIU Zhi-juan, DAI Shu-wei, LI Yong, XIE Wen-juan, CHEN Fu
    2014, 13(7): 1546-1554.  DOI: 10.1016/S2095-3119(14)60809-1
    Abstract ( )   PDF in ScienceDirect  
    Based on climate data from 254 meteorological stations, this study estimated the effects of climate change on rice planting boundaries and potential yields in the southern China during 1951-2010. The results indicated a significant northward shift and westward expansion of northern boundaries for rice planting in the southern China. Compared with the period of 1951-1980, the average temperature during rice growing season in the period of 1981-2010 increased by 0.4°C, and the northern planting boundaries for single rice cropping system (SRCS), early triple cropping rice system (ETCRS), medium triple cropping rice system (MTCRS), and late triple cropping rice system (LTCRS) moved northward by 10, 30, 52 and 66 km, respectively. In addition, compared with the period of 1951-1980, the suitable planting area for SRCS was reduced by 11% during the period of 1981-2010. However, the suitable planting areas for other rice cropping systems increased, with the increasing amplitude of 3, 8, and 10% for ETCRS, MTCRS and LTCRS, respectively. In general, the light and temperature potential productivity of rice decreased by 2.5%. Without considering the change of rice cultivars, the northern planting boundaries for different rice cropping systems showed a northward shift tendency. Climate change resulted in decrease of per unit area yield for SRCS and the annual average yields of ETCRS and LTCRS. Nevertheless, the overall rice production in the entire research area showed a decreasing trend even with the increasing trend of annual average yield for MTCRS.
    Impacts of Climate Change on Rice Yield in China From 1961 to 2010 Based on Provincial Data
    CHEN Chao, ZHOU Guang-sheng , ZHOU Li
    2014, 13(7): 1555-1564.  DOI: 10.1016/S2095-3119(14)60816-9
    Abstract ( )   PDF in ScienceDirect  
    The impacts of climate change on rice yield in China from 1961 to 2010 were studied in this paper, based on the provincial data, in order to develop scientific countermeasures. The results indicated that increase of average temperature improved single cropping rice production on national level by up to 11% relative to the average over the study period, however, it resulted in an overall loss of double cropping rice by up to 1.9%. The decrease of diurnal temperature range (DTR) in the major producing regions caused the decrease by up to 3.0% for single cropping rice production and 2.0% for double cropping rice production. Moreover, the contribution of precipitation change reached about 6.2% for single cropping rice production, but no significant effect for double cropping rice production in recent 50 years.
    Climate Change Impact and Its Contribution Share to Paddy Rice Production in Jiangxi, China
    LI Wen-juan, TANG Hua-jun, QIN Zhi-hao, YOU Fei, WANG Xiu-fen, CHEN Chang-li, JI Jian-hua , LIU Xiu-mei
    2014, 13(7): 1565-1574.  DOI: 10.1016/S2095-3119(14)60811-X
    Abstract ( )   PDF in ScienceDirect  
    In the study, an improved approach was proposed to identify the contribution shares of three group factors that are climate, technology and input, social economic factors by which the grain production is shaped. In order to calibrate the method, Jiangxi Province, one of the main paddy rice producers in China was taken as an example. Based on 50 years (1961-2010) meteorological and statistic data, using GIS and statistical analysis tools, the three group factors that in certain extent impact China’s paddy rice production have been analyzed quantitatively. The individual and interactive contribution shares of each factor group have been identified via eta square (η2). In the paper, two group ordinary leasr square (OLS) models, paddy models and climate models, have been constructed for further analysis. Each model group consists of seven models, one full model and six partial models. The results of paddy models show that climate factors individually and interactively contribute 11.42-15.25% explanatory power to the variation of paddy rice production in the studied province. Technology and input factors contribute 16.17% individually and another 8.46% interactively together with climate factors, totally contributing about 25%. Social economic factors contribute about 7% of which 4.65% is individual contribution and 2.49% is interactive contribution together with climate factors. The three factor groups individually contribute about 23% and interactively contribute additional 41% to paddy rice production. In addition every two of the three factor groups also function interactively and contribute about 22%. Among the three factor groups, technology and input are the most important factors to paddy rice production. The results of climate models support the results of paddy models, and display that solar radiation (indicated by sunshine hour variable) is the dominate climate factor for paddy rice production.
    Spatio-Temporal Changes in the Rice Planting Area and Their Relationship to Climate Change in Northeast China: A Model-Based Analysis
    XIA Tian, WU Wen-bin, ZHOU Qing-bo, YU Qiang-yi, Peter H Verburg, YANG Peng, LU Zhongjun
    2014, 13(7): 1575-1585.  DOI: 10.1016/S2095-3119(14)60802-9
    Abstract ( )   PDF in ScienceDirect  
    Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over the period of 1980-2010 and to analyze their relationship to climate change. To do so, the CLUE-S (conversion of land use and its effects at small region extent) model was first updated and used to simulate dynamic changes in the rice planting area in NEC to understand spatio-temporal change trends during three periods: 1980-1990, 1990-2000 and 2000-2010. The changing results in individual periods were then linked to climatic variables to investigate the climatic drivers of these changes. Results showed that the NEC rice planting area expanded quickly and increased by nearly 4.5 times during 1980-2010. The concentration of newly planted rice areas in NEC constantly moved northward and the changes were strongly dependent on latitude. This confirmed that climate change, increases in temperature in particular, greatly influenced the shift in the rice planting area. The shift in the north limit of the NEC rice planting area generally followed a 1°C isoline migration pattern, but with an obvious time-lag effect. These findings can help policy makers and crop producers take proper adaptation measures even when exposed to the global warming situation in NEC.
    Geographic Variation of Rice Yield Response to Past Climate Change in China
    YANG Jie, XIONG Wei, YANG Xiao-guang, CAO Yang , FENG Ling-zhi
    2014, 13(7): 1586-1598.  DOI: 10.1016/S2095-3119(14)60803-0
    Abstract ( )   PDF in ScienceDirect  
    Previous studies demonstrated climate change had reduced rice yield in China, but the magnitude of the reduction and the spatial variations of the impact have remained in controversy to date. Based on a gridded daily weather dataset, we found there were obvious changes in temperatures, diurnal temperature range, and radiation during the rice-growing season from 1961 to 2010 in China. These changes resulted in a significant decline of simulated national rice yield (simulated with CERES-Rice), with a magnitude of 11.5%. However, changes in growing-season radiation and diurnal temperature range, not growing-season temperatures, contributed most to the simulated yield reduction, which confirmed previous estimates by empirical studies. Yield responses to changes of the climatic variables varied across different rice production areas. In rice production areas with the mean growing-season temperature at 12-14°C and above 20°C, a 1°C growing-season warming decreased rice yield by roughly 4%. This decrease was partly attributed to increased heat stresses and shorter growth period under the warmer climate. In some rice areas of the southern China and the Yangtze River Basin where the rice growing-season temperature was greater than 20°C, decrease in the growing-season radiation partly interpreted the widespread yield decline of the simulation, suggesting the significant negative contribution of recent global dimming on rice production in China’s main rice areas. Whereas in the northern rice production areas with relatively low growing-season temperature, decrease of the diurnal temperature range was identified as the main climatic contributor for the decline of simulated rice yield, with larger decreasing magnitude under cooler areas.
    Interpretation of Climate Change and Agricultural Adaptations by Local Household Farmers: a Case Study at Bin County, Northeast China
    YU Qiang-yi, WU Wen-bin, LIU Zhen-huan, Peter H Verburg, XIA Tian, YANG Peng, LU Zhongjun, YOU Liang-zhi , TANG Hua-jun
    2014, 13(7): 1599-1608.  DOI: 10.1016/S2095-3119(14)60805-4
    Abstract ( )   PDF in ScienceDirect  
    Although climate change impacts and agricultural adaptations have been studied extensively, how smallholder farmers perceive climate change and adapt their agricultural activities is poorly understood. Survey-based data (presents farmers’ personal perceptions and adaptations to climate change) associated with external biophysical-socioeconomic data (presents real-world climate change) were used to develop a farmer-centered framework to explore climate change impacts and agricultural adaptations at a local level. A case study at Bin County (1980s-2010s), Northeast China, suggested that increased annual average temperature (0.6°C per decade) and decreased annual precipitation (46 mm per decade, both from meteorological datasets) were correctly perceived by 76 and 66.9%, respectively, of farmers from the survey, and that a longer growing season was confirmed by 70% of them. These reasonably correct perceptions enabled local farmers to make appropriate adaptations to cope with climate change: Longer season alternative varieties were found for maize and rice, which led to a significant yield increase for both crops. The longer season also affected crop choice: More farmers selected maize instead of soybean, as implicated from survey results by a large increase in the maize growing area. Comparing warming-related factors, we found that precipitation and agricultural disasters were the least likely causes for farmers’ agricultural decisions. As a result, crop and variety selection, rather than disaster prevention and infrastructure improvement, was the most common ways for farmers to adapt to the notable warming trend in the study region.