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20 April 2016, Volume 37 Issue 02

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Effects of Reducing Nitrogen and Biochar Application on CO₂ and N₂O Emissions from Summer Maize-Winter Wheat Field in North China

FAN Jing-wei，BAI Jin-hua，REN Huan-yu, HAN Xue, DIAO Tian-tian,GUO Li-ping

2016, 37(02):  121-130.  doi:10.3969/j.issn.1000-6362.2016.02.001

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This experiment was conducted in Xinxiang, Henan province from June 2013 to June 2014. Four treatments were designed including farmers common practice (F, 250kg·ha^-1),80% F (LF, 200kg·ha^-1),80% F + biochar(LFC) and no fertilizer (CK) to measure the dynamic emissions of CO₂ and N₂O from a summer maize-winter wheat field using static chamber and gas chromatography method. The results indicated that, (1)soil CO₂ emission was 21.8-1022.7mg·m^-2·h^-1 for this agriculture system and was significantly influenced by soil temperature and moisture. Soil moisture was more important for the N₂O emissions during the summer maize growth period while N₂O emissions during winter wheat growth period was more significantly influenced by the soiltemperature. The cumulative CO₂ emissions under LF and LFC treatments were significantly lower than F treatment especially during the winter wheat growing season. (2)Soil N₂O emission was significantly influenced by fertilizer application and irrigation. N₂O emissions during the fertilization period accounted for 73.9%-74.5% and 40.5%-43.6% of cumulative N₂O emissions in summer maize and winter maize growing season, respectively. The peak of emission fluxes was primarily affected by fertilizer rate while irrigation determined the occurrence time when emissions would peak and could affect the mitigation effect of practices. Reduce the nitrogen application rate to 200kg·ha^-1 from 250kg·ha^-1 could decrease cumulative N₂O emissions by 15.7%-16.8% and 18.1%-18.5% during summer maize and winter wheat growing seasons, respectively, therefore decreasing nitrogen application is an effective N₂O mitigation practice for high-yielding and intensive farmland. Biochar application did not show no significant influence on soil N₂O mitigation of biochar application at suitable nitrogen level(200kg·ha^-1) in the short term. (3)N₂O emission factors of applied nitrogen were 0.60% and 0.56% for F and LF treatment, respectively, indicating that reducing the nitrogen application rate is an appropriate measure to mitigate greenhouse gas emissions without impact on crop yields in intensive farmlands in North China.

Effects of Biochar and Straw Return on Mineral Nitrogen and pH of the Surface Soil in Farmland of the North China Plain

ZHANG Xing, LIU Xing-ren, LIN Guo-lin, ZHANG Qing-wen, ZHANG Qing-zhong,WANG Qin

2016, 37(02):  131-142.  doi:10.3969/j.issn.1000-6362.2016.02.002

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Based on the location experiment, which consisted of four treatments (CK, C1, C2, SR) with three replications: CK (single NPK fertilizer), C1 (biochar 4.5t·ha^-1·y^-1+NPK fertilizer) and C2 (biochar 9.0t·ha^-1·y^-1 + NPK fertilizer) and SR (straw return + NPK fertilizer). The effects of biochar and straw return on mineral nitrogen (N) and pH of the surface soil in farmland of the North China Plain in 2014 and 2015 were studied. Results showed that the dynamic trend of soil mineral N content (NO₃--N, NH4⁺-N) were similar. Application of biochar and straw return significantly increased soil NO₃--N (P<0.05). However, there were no significant effects on soil NH4⁺-N. Compared with SR treatment, C2 treatment was more helpful to increase soil NO₃--N. The mineral N in the soil was dominated by NO₃--N, and NH4⁺-N was kept at a low level. The contents of soil mineral N in the whole growth period of winter wheat was higher than in that of summer maize. Biochar significantly increased soil pH(P<0.05), and soil NO3--N was negatively correlated with soil pH(P<0.05), and soil NH4⁺-N was not correlated with soil pH. But soil NO₃--N and NH4⁺-N were positively correlated with soil moisture content in each treatment(P<0.05). In short, adding biochar had greater potential in slowing N transformation, reducing N mobility and so on. The results can be used a scientific reference on improving soil quality and reducing soil N loss in farmland.

Effects of Atmospheric Environment on the Particulate Matters in the Fattening Pig Barns

LIU Yang, DONG Hong-min, TAO Xiu-ping, CHEN Yong-xing，SHANG Bin, XU Wen-qian

2016, 37(02):  143-148.  doi:10.3969/j.issn.1000-6362.2016.02.003

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Measurement points were set inside and outside the barns to monitor PM2.5(diameter of particulate matter ≤2.5μm), PM10(diameter of particulate matter ≤10μm) and TSP(diameter of particulate matter ≤100μm ) concentrations on a swine farm in Changping, suburb Beijing for a full year（2014-09-30 to 2015-08-29）. Comparison and statistical analysis of the monitoring results were done with data from the Changping national environmental monitoring station. Results showed that the concentration ranges of PM2.5 inside and outside the barns were 23-245μg·m^-3 and 11-372μg·m^-3, respectively, PM10 were 113-1182μg·m^-3 and 25-444μg·m^-3, respectively, and TSP were 334-4396μg·m^-3 and 31-742μg·m^-3, respectively. The concentrations of PM10 and TSP inside the barns were much higher than that outside. The concentration of PM2.5 inside the pig barns was mostly influenced by the atmospheric environment, but the particulate matters larger than 2.5μm mostly came from the breeding process.

Spatiotemporal Variation of Blue-Green Water under Typical Reference Years in the Weihe River Basin

ZHAO An-zhou, ZHU Xiu-fang, PAN Yao-zhong, LIU Xin

2016, 37(02):  149-157.  doi:10.3969/j.issn.1000-6362.2016.02.004

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In order to understand the spatiotemporal pattern difference of blue-green water in typical reference years on a watershed scale, this study selected the Weihe River Basin in northwestern of China to analyze the spatiotemporal distribution pattern difference of blue-green water, and obtained the typical reference years by using standardized precipitation index(SPI) and precipitation anomaly index(Pa). The results showed that: (1)the years of 1983, 1997 and 2007 were determined as wet year, dry year and normal year, respectively. (2)Calibration and validation results showed a similar change trend between simulated and observed discharges, and the SWAT can be used to predict hydrological processes in Weihe River Basin. (3)Change of the green water was relatively stable in the typical reference years, and the green water coefficients were 82.06%, 93.47% and 87.72% in the wet year, dry year and normal year, respectively. (4)Spatially, the blue-green water decreased from southeast to northwest in Weihe River Basin. The spatial distribution of green water indicated that the proportion of green water in the wet year (1983) or areas (southeast) was lower than the normal and dry year (1997) or areas (north).

Evapotranspiration Characteristics and Crop Coefficient Estimation of Paddy Rice

GAO Lei, SHEN Shuang-he, SHAO Li-ying, CHU Rong-hao, TAN Shi-qi

2016, 37(02):  158-165.  doi:10.3969/j.issn.1000-6362.2016.02.005

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Based on evapotranspiration data in a lysimeter of paddy rice, the data of biological and meteorological during the growth season in Nanjing in 2012, the reference evapotranspiration (ET0), actual evapotranspiration (ETc), and actual crop coefficient (Kc) of paddy rice were calculated, and the crop coefficient model was established. The results showed that the daily ET0 changed as a single peak curve, with the peak at tillering-jointing stage. While the daily ETc changed as a two-peak type, with the peak at tillering and heading stages respectively. Both ET0 and ETc obvious varied as seasonal. The actual crop coefficient (Kc) was consistent with the K corrected by FAO, but their values generally differed. The relationship between establishing model and its affected factors was well, with their R2 = 0.887. A model describing relationships between daily Kc and biological factor (LAI) as well as environmental factors (air temperature, net solar radiation) was established and its estimate agreed very well with the actual crop coefficient, and the model was capable of predicting ETc of paddy rice (R2 = 0.943) from a formula ETc=KcET0 by use of the Kc estimates. This model could help simplify computation of crop coefficient and define the effect of different factors and know well its dynamic characteristics.

Temporal and Spatial Change and Causes Analysis of the Reference Crop Evapotranspiration in Farming-Pastroral Ecotone of Northern China

LI Ying-jie, YAN Jun-ping, WANG Peng-tao

2016, 37(02):  166-173.  doi:10.3969/j.issn.1000-6362.2016.02.006

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Based on the FAO Penman-Monteith equation and the meteorological dataset in farming-pastroral ecotone of northern China during 1961 to 2013，ET0 and its sensitivity coefficients to meteorological factors were studied by using trend analysis and spatial interpolation methods．The results showed that the mean annual ET0 was 839-1097mm and decreased slightly at the rate of 0.21mmy^-1 during the study period. 61% meteorological stations in eastern Qinhai, mid-Gansu and the northern Shaanxi plateau showed an increasing trend of 0.85mm·y^-1（P＜0.05），while in Horqin sandy land and the western Liaoning the ET0 declined significantly. The meteorological factors’ contribution to ET0 was influenced by two aspects: the sensitivity coefficient and relative change rate of the meteorological factors. The sensitivity analysis showed the relative humidity was the most sensitive factor among the four main meteorological factors, followed by the wind speed, sunshine hours, mean temperature. But the wind speed decreased dramatically at the rate of 0.0154m-s^-1y^-1（P＜0.001）in recent 53 years, and the comprehensive result was that wind speed had the largest contribution to ET0, followed by relative humidity, which illustrating that the declination of ET0 was due to the deceleration of wind speed.

Application of Bias Correction Method for Simulated Climate Data in Projection of Crop Climatic Potential Productivity ——A Case Study of Winter Wheat in Jiangsu

TAO Su-lin, SHEN Shuang-he, LI Yu-hong, GAO Ping

2016, 37(02):  174-187.  doi:10.3969/j.issn.1000-6362.2016.02.007

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A bias correction model for simulated climate data was constructed. The nonlinear transfer function between simulations and observations and the parameters for variation correction were determined based on historical simulations outputting from a regional climate model RegCM4 coupled with a global model BCC_CSM1.1 (Beijing Climate Center Climate System Model version 1.1) and the observations during baseline period from 1961-1990. The effectiveness of bias correction model was verified using simulated climate data and observed data during validation period from 1991-2005. This model was then used to correct climate data under RCP (Representative Concentration Pathway) scenarios during future period from 2021-2050. Meanwhile, the spatial patterns of winter wheat climatic potential productivity of Jiangsu were projected via productivity decay method under future scenario climates. The results indicated that it was effective to apply bias correction method for simulated climate data in projection of crop climatic potential productivity. The bias correction model with mean value and variation information was an excellent way of correcting simulated climate data at daily scale in Jiangsu. The bias of simulated temperature, radiation, evapotranspiration in autumn and winter as well as precipitation in winter and spring was reduced obviously after correction. Then, on the basis of bias correction, the maturity date of winter wheat in Jiangsu was projected between 153-175 and 153-174 respectively under RCP4.5 and RCP8.5 scenarios, and would advance obviously compared with baseline. The estimated climatic potential productivity of winter wheat was projected between 10335-14368kg·ha^-1 and 9991-13708kg·ha^-1 respectively, and would tend to be lower than that during baseline period. Accordingly, the coefficient of variation of climatic potential productivity was projected between 7.6%-14.6% and 7.5%-13.6% respectively, and would increase compared with baseline, which indicated a tendency towards unstable for climatic potential productivity of winter wheat in Jiangsu. Moreover, during future period, the climatic potential productivity of winter wheat would remain relatively high (≥12501kg·ha^-1) in central and northern Xuzhou, northeastern Lianyungang, western Suqian and southeastern Yancheng under RCP4.5 and RCP8.5 scenarios. Thus, the cultivated land for winter wheat in these regions should be guaranteed by the government of Jiangsu. Our results suggested a consideration of bias correction for simulated climate data using observations of study region before estimating crop climatic potential productivity, in order to enhance the credibility of the projections.

Morphology of Middle-season Hybrid Rice in Hubei Province and Its Yield Under Different Waterlogging Stresses

WU Qi-xia，ZHU Jian-qiang，YAN Jun，HUANG Cheng-tao

2016, 37(02):  188-198.  doi:10.3969/j.issn.1000-6362.2016.02.008

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In Hubei plain area, there is a plenty of rainfall in summer, so that rice plants are liable to suffer from waterlogging damage. In order to know the influences of waterlogging on hybrid rice in growth and yield, Fengliangyouxiang 1 (one of the hybrid rice varieties) was used as the test material, and the experiments of waterlogging stresses on it were made individually in the jointing, booting and filling stages, the experimental treatments were designed as different combinations of waterlogged depth and waterlogged time (3, 6 and 9 days). The results showed that, after waterlogging stress, the rice height and the internode length all present elongation. At filling stage and booting stage under waterlogging stress, the plant height growth rate was greater than the jointing stage. The linear relationship between the hybrid rice height increase (YPH), internode height (YIL) and waterlogged days (D), waterlogged depth (H) was significant, correlation coefficient was up to more than 0.9000, and the waterlogged depth had a greater influence on the plant height and internode length than waterlogged days. The reduction of output that caused by waterlogging stress at different stages of rice was different, the order was booting stage＞jointing stage＞filling stage. The linear relationship between the relative yield (Ry) and D, H was significant, correlation coefficient was up to more than 0.9000, and waterlogged days had a greater influence on the yield than waterlogged depth at jointing and filling stage, in contrast, at booting stage. As far as yield component was concerned, waterlogging stress at jointing stage lead to yield loss mainly because seed setting rate decreased, while at booting stage 1000-grain weight and seed setting rate decreased, at filling stage mainly in the following aspects, first, the decline of seed setting rate, then, the decrease of effective ears. At jointing stage, booting stage and filling stage under waterlogging stress, the relative moisture index of the lower panicle was 0.69%-44.01%, 20.87%-71.14% [100% for completely submergence for 9 days (aliased as CS9)] and 3.15%-81.84% respectively, the relative moisture index of the central panicle was 4.49%-32.36%, 14.31%-62.21%（100% for CS9）and 10.02%-66.89% respectively, and the relative moisture index of upper panicle was -0.77%-14.72%, 7.64%-50.10%（100% for CS9）and 2.75%-59.66%.

Effects on Cooling down and Increasing Yield of Sweet Pepper of A Novel Cultivation Method: Soil Ridge Substrate-Embedded in Chinese Solar Greenhouse

FU Guo-hai, LIU Wen-ke

2016, 37(02):  199-205. 

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In Chinese solar greenhouse, in order to deal with the problem of high temperature stress in sweet pepper growth period in spring, a novel cultivation method named soil ridge substrate-embedded cultivation (SRSC) was designed. In this experiment, four kinds of treatments were set such as soil ridge (S treatment), soil ridge substrate-embedded of PE (P treatment), soil ridge substrate-embedded of wire (W treatment) and single PE groove (CK) which as contrast. Root zone temperatures were observed from 12：00 to 16：00 every day in sweet pepper maturation stage (May to June), and parameters of growth and yield of sweet pepper were measured and analysed at different times. Results showed that root zone temperatures of S, P and W were 1.50, 2.17 and 1.47℃ lower than CK, respectively, and P and W could effectively buffer high root zone temperature, and the effect of P was slightly better than W. The plant height, stem diameter, chlorophyll content, dry shoot weight and fresh shoot weight of sweet pepper cultivated on S, P and W were significantly higher than that of CK, and the effect of W was the most obvious. The fresh root weight of soilless cultivation was significantly less than sweet pepper cultivated on other ridges, but dry shoot and root weight were decreased by high root zone temperature. In addition, the fruit number of S was significantly less than that of other three treatments when picking at first time, it suggested that soilless cultivation could accelerate the growth process of sweet pepper. The yield of W was 3.78kg·m^-2, and it increased by 80.9%, 31.3%, and 51.8% respectively than S, P and CK. In short, W enhanced the root zone temperature buffer capacity, and significantly improved the yield of sweet pepper, and it had important application value in the high temperature environment production in Chinese solar greenhouse.

Effect of Low Temperature at Flowering Stage on Late Rice Dry Matter Accumulation and Distribution

BAI Guang-zhi, LIU Shou-dong, YU Yan-wen, YANG Zai-qiang, YIN Jian-min

2016, 37(02):  206-212.  doi:10.3969/j.issn.1000-6362.2016.02.010

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To study the impact of low temperature during flowering stage to photosynthesis, grain filling process, and dry matter accumulation and distribution, we took Guangliangyouxiang 66 as a material in artificial control test in Nanjing University of Information Science & Technology from August to October in 2014. The low stress temperature was set as 22℃/17℃(day/night), and processing time was 2d, 4d, 6d and 8d (denoted as T2d, T4d, T6d and T8d), and 32℃/25℃ (day/night) as the control (CK). The results showed that: (1)after low temperature treatment, maximum photosynthetic rate (Pmax) of T2d changed smaller, and that of T4d and T6d were respectively 11.66% and 11.66% lower than CK. Pmax of T8d was only 17.25μmol·m^-2·s^-1, which decreased by 28.54% than CK. In addition, the light saturation point (LSP) reduced after low temperature treatment, and the light compensation point (LCP) increased significantly. Compared with CK, T2d, T4d, T6d, T8d LSP was reduced by 6.68%, 8.08%, 8.63%, 10.87%, but LCP increased 2, 3, 4, 6 times. This means low temperature treatment can reduce the photosynthetic capacity of late rice leaf. (2)When modeling grain fitting process of different treatments, we found that with more treatment time, the time required to reach the maximum filling rate(T-GRmax) was more, the largest grain weight(A) and time of the active period (T90) were less, which resulting a decline of average filling rate (GR). And this indicated that the low temperature will slow the process of rice grain filling. (3)The longer processing time, the lower the seed setting of rate rice. Treatment no more than 2d, the seed setting would not change significantly, but treatment more than 4d would result seed setting significant decline. Compared to CK, seed setting of T8d reduced by 34.39%. (4)The total dry matter was negatively correlated with low temperature treatment time, and the total dry matter would significant reduced if low temperature treatment after 6d. That of T8d showed a 28.05% decline compared to CK, which leaf and spike contributed obviously. And after 4d treatment, dry matter of leaf and spike would significant decline. Compared to CK, dry matter of leaf and spike of T8d were reduced by 42.57% and 38.07%. Result showed that low temperature at flowering stage could inhibit late rice photosynthesis. More than 4d treatment could significantly reduce the seed setting, slow down the process of grain filling, and those were adverse to the yield formation.

Series Lines on Change of Leaf Temperature Difference of Quercus variabilis with Solar Radiation and Wind Speed

WANG Pei-shu, WANG Wei-hong, CHEN Jing-ling, WANG Qian, LI Guo-huai

2016, 37(02):  213-221.  doi:10.3969/j.issn.1000-6362.2016.02.011

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In order to explore the effect of solar radiation, air temperature and wind speed on leaf temperature (LT) of Quercus variabilis, and to determine the consistency of LT and the series lines of Gates climate space, LT and air temperature (Ta) and solar radiation (R) were measured in clear day with the conditions of controlled wind speeds. The relationship between leaf air temperature difference (LATD) and solar radiation at different wind speeds was studied. The series lines of climate space of Quercus variabilis were determined by using Gates theory climate space and graphic method. The results showed LATD of Quercus seedlings increased linearly with the radiation increasing. Canopy temperature depression (CTD) of Quercus variabilis also increased with radiation increasing, but affected by the wind speed. CTD tended to be zero when wind speed was 0.8m·s^-1. CTD of Quercus seedlings changed as R linearly with the radiation increasing and different wind speeds. The linear relationship was series lines and decreased with wind speed increasing. The series lines were in accordance with the upper limits of Gates theory climate space. The upper limit of climate space could be expressed by adding up biological maximum temperature (BMT) and CTD value on series lines with different wind speeds.

Effect of Shading on Photosynthetic Parameters in Greenhouse Cucumber Leaves

XIONG Yu, YANG Zai-qiang, XUE Xiao-ping, LI Jun

2016, 37(02):  222-230.  doi:10.3969/j.issn.1000-6362.2016.02.012

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A cucumber cv.‘JinYou35’was chosen as an experimental material to examine the effects of shading on the photosynthetic parameters and fluorescence parameters of the young cucumber leaves. Four levels of light intensity were set in greenhouse during 25 days which comprise full light intensity(CK), 20% of full light intensity(T1), 40% of full light intensity(T2) and 60% of full light intensity(T3). The results showed that: shading make the content of chlorophyll a, chlorophyll b and total chlorophyll increased in different degrees, while the value of chlorophyll a/b decreases. After shading 25 days, the content of chlorophyll a under the block 60%, 40%, 20% of the light were 30.6%, 16.5%, 15.4% higher than the control treatment respectively. The light saturation point(LSP), maximum photosynthetic rate (Pmax) and the apparent quantum efficiency (AQE) of young cucumber leaves which under shade processing decreased, while the light compensation point (LCP) increased with the increase of the days of treatment. Treating after 25 days, the stomatal conductance（Gs）of blocking 60%, 40%, 20% of light were 57.9%, 57.4%, 47.3% smaller than the controlled treatment respectively, and the transpiration rates(Tr) were 34.7%, 34.0% and 52.4% lower than the controlled treatment respectively. With the increase of the days of treatment, the stomatal limitation (Ls) and water use efficiency (WUE) of cucumber leaves were shown an increasing trend. The potential efficiency of photosystem II (Fv/Fm) of shading cucumber leaves shown a downtrend roughly with the increased of shading days, and the photochemical quenching (qP) decreased, while the non-photochemical quenching (qN) increased. The study confirmed that shading made the chlorophyll content of cucumber leaves increased, affected photosynthesis.

Influence of Elevated Atmospheric Temperature and CO2 Concentration on Plant and Soil N Concentration and Yield of Early Rice in Hubei

CAI Wei-wei, AI Tian-cheng,WAN Yun-fan,LI Jian-ling, GUO Chen

2016, 37(02):  231-237.  doi:10.3969/j.issn.1000-6362.2016.02.013

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Using a modified open-top chamber（OTC）method to simulate relative 60μL·L^-1 CO₂ concentration increment and 2℃ temperature rise scenario in early rice field to study their impacts on the plant total nitrogen, soil N concentration and yield in Hubei. The experimental design consisted of four treatments arranged in randomized blocks and three replicates. Treatments were as follows: (1)the control OTC(CK, ambient CO₂ concentration and temperature), (2)elevated air temperature by 2℃(IT), (3)elevated CO₂ concentration by 60μL·L^-1(IC), (4)air temperature increase by 2℃ plus 60μL·L^-1 CO₂ concentration elevated(IT+IC). Surveyed the plant total nitrogen content, soil ammonium nitrogen, soil nitrate nitrogen, yield and yield components of early rice. The results showed that: (1)there was a significant increase on the plant total nitrogen content during the early growth periods (especially during tillering) when atmospheric temperature and CO₂ concentration rose alone and the two of them rose synchronously, but there were no obvious differences after tillering, so did the soil ammonium nitrogen. (2)Elevated temperature had a significant decrease on nitrate nitrogen content during jointing, maturity stage, and it would increase heading stage’s, while it would have a positive effect on nitrate nitrogen during jointing, maturity stage, and have a negative impact on it when CO₂ concentration elevated. (3)Compared to the control, there was a significant increase on early rice grain yield by 13.4% when CO₂ concentration rose, while there were no differences when only temperature rose or CO₂ concentration elevated alone.

Spatial Distribution of Rice Drought Frequency during Different Growth Periods in Sichuan Basin

LIU Yan-yan, ZHANG Yu-fang, WANG Ming-tian, CHEN Chao, PAN Xue-biao, ZHOU Xue-hui

2016, 37(02):  238-244.  doi:10.3969/j.issn.1000-6362.2016.02.014

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Drought significantly influences rice growth and development and has caused great loss of rice production in the Sichuan basin. The basin was divided into five rice growing regions based on its landforms and cropping systems in this paper. Authors analyzed the spatial distribution characteristics of drought frequency for each growth period of rice in the basin in terms of drought assessment index, using historic daily weather data from 102 meteorological monitoring stations between 1980 and 2014 and the phonological data from 32 agro-meteorological observation stations. The results showed that drought frequency was over 90% during the transplanting and tillering stages in parts of the middle and southern basin. During the periods from tillering to jointing stage and from jointing to booting stage, the drought frequency varied between 50% and 90% over the majority area of the basin. The frequency occurred during the periods from booting to heading stage and from heading to mature stage was lower compared with that during the other stages. It was about 50% during the period from booting and heading stage over most of the basin, apart from parts of the western, central basin and northeastern basin where the frequency was around 70%-84%. And the frequency was about 50%-70% during the period from heading to mature over most of the basin.

Spatial Downscaling Simulation of Monthly Precipitation Based on TRMM 3B43 Data in the Western Sichuan Plateau

ZHENG Jie, LV Li, FENG Wen-lan, TU Kun

2016, 37(02):  245-254.  doi:10.3969/j.issn.1000-6362.2016.02.015

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Using TRMM 3B43 data, MODIS-NDVI, DEM, meteorological data of observation stations during 2001-2013, a multiple linear regression model was built among TRMM 3B43 monthly precipitation and longitude, latitude, altitude, aspect, NDVI factor as downscaling model of monthly precipitation data in the Western Sichuan Plateau based on the analysis of the lag of vegetation response to precipitation. Then, combined with regression equation and residuals, interpolation method was adopted to obtain monthly precipitation data with 1km spatial resolution. Finally, the accuracy of simulated data obtained by downscaling model was tested by the correlation analysis and error detection between the simulated results and the observation data of 16 meteorological stations in the study area. The results showed as follows: (1) Precipitation simulated by downscaling model based on TRMM 3B43 data had a high precision in all meteorological observation stations. Daocheng site displayed the highest accuracy, the correlation coefficient between simulation results and observed values attained 0.9839, while Xiaojin site displayed the lowest accuracy, the correlation coefficient was 0.8781. (2) The precipitation simulated by downscaling model displayed high accuracy in the whole study area at both monthly and yearly time scale. The accuracy of simulated results from May to October was significantly higher than other months, as well as typical wet year (2012) was higher than dry year (2006). (3) The precipitation simulated by downscaling model displayed high accuracy to the observation data on the whole(R=0.9499, Bias=0.0866), while the value of simulated precipitation was slightly higher. (4) Compared to the original data TRMM 3B43, the simulated data by downscaling model guaranteed the accuracy and improved the spatial resolution. So, this method could provide an effective way to produce a more sophisticated precipitation data with higher spatial resolution.