稻麥輪作田下墊面的感熱和潛熱通量特征分析
發(fā)布時間：2019-03-12 14:09
【摘要】：感熱和潛熱通量是地表能量平衡的重要組成部分,對其的定量了解,不僅是大氣動力熱力過程分析的基礎,也是農業(yè)生態(tài)等研究的核心內容。長江中下游農田以水稻和小麥為主要耕作物,對稻麥輪作田進行通量觀測能夠更好地理解長江中下游區(qū)域大氣邊界層能量交換特征。因此,本文基于2015年7月9日到2016年5月18日,江蘇鹽城東臺市郊稻麥輪作田上方的通量觀測數(shù)據,對稻麥輪作田下墊面的通量變化特征進行了分析,探討了不同生長期,下墊面的平均通量和能量分配特征,重點分析了不同時期通量的日變化特征及下墊面溫濕度和風速對能量分配的影響,最后,對比了大孔徑閃爍儀和渦相關觀測系統(tǒng)的觀測數(shù)據,檢驗了儀器的可靠性。主要結論如下:(1)平均通量分析表明,在白天,小麥返青期的平均感熱通量最大,而水稻拔節(jié)期的平均潛熱通量最大。在夜間,下墊面仍然存在向上的潛熱通量。在停耕期和小麥出苗期,整個下墊面接收到的能量要小于它向大氣傳遞的感熱和潛熱通量。在整個觀測過程中,各時期(H+LE)/Rn的平均值不超過80%,H/Rn的平均值不超過18%,農田下墊面主要以潛熱通量的方式向大氣傳遞能量。(2)日變化特征分析表明,水稻、裸地和小麥下墊面情況下感熱通量的日變化特征十分接近,整個觀測期間,感熱通量的平均峰值為46.08 Wm-2。對能量分配的平均日變化特征分析表明,在水稻的生長周期,(H + LE)/Rn和LE/Rn的日變化特征較為一致,它們在水稻各個時期的日變化趨勢分別為:先減后增型(插秧期),逐漸增長型(拔節(jié)期),平穩(wěn)波動型(抽穗期)和逐漸增長型(成熟期)。而H/Rn的值在整個水稻生長期內都為先增后減型,其最大值一般出現(xiàn)在10:00左右。在小麥的種植期,(H+LE)/Rn和LE/Rn的日變化特征也較為一致,都隨著小麥的生長,由逐漸增長型(出苗期,越冬期和返青期)轉變?yōu)槠鸱鲩L型(拔節(jié)期和成熟期)。H/Rn的日變化特征主要分為先增后減型(出苗期,越冬期和成熟期)和平穩(wěn)波動型(返青期和拔節(jié)期)。當下墊面為裸地時,(H+ LE)/Rn , LE/Rn和H/Rn的日變化特征均為波動型。(3)對土壤溫濕度及地表風速的分析表明,在水稻種植期,各變量對能量分配的影響作用都較為獨立,能量分配主要受土壤濕度和風速的影響。土壤濕度的增加,略微增大了H/Rn的值,降低了LE/R 的值,而風速的增大,增大了LE/Rn的值。在小麥種植期,土壤溫度和濕度共同影響了地表能量分配,隨著土壤溫度的增加,對應的土壤濕度減小,H/Rn的值減小,LE/Rn的值增大。在整個觀測期間,H/Rn和LE/Rn的日變化同時受土壤溫濕度及風速的日變化的影響,當土壤溫度增大時,土壤相對濕度減小,風速逐漸增大且增長速度逐漸降低,LE/Rn的值逐漸增大,而H/Rn始終保持穩(wěn)定。(4)對水稻抽穗期通量觀測數(shù)據的分析表明,大多數(shù)情況下,LAS觀測的感熱通量都要大于EC所觀測的值。結合源區(qū)模型,可以發(fā)現(xiàn),儀器東側的一片桑樹園影響了兩個儀器的觀測結果。由于桑樹園上方的感熱通量大于水稻田上方的感熱通量。當桑樹園貢獻較大時,HLAS的值總是會大于HEC的值。而當桑樹園對兩個儀器貢獻較一致時,兩個儀器觀測得到的感熱通量也較為接近。兩種儀器觀測的差異是由桑樹園所引起的下墊面不均勻性造成的。
[Abstract]:The heat and latent heat flux is an important part of surface energy balance, and its quantitative understanding is not only the basis of the analysis of the dynamic process of the atmospheric power, but also the core content of the agricultural ecology. The energy exchange characteristics of the atmospheric boundary layer in the middle and lower reaches of the Yangtze River can be better understood in the middle and lower reaches of the Yangtze River. Therefore, on the basis of the flux observation data from July 9,2015 to May 18,2016, the flux change characteristics of the wheat and wheat rotation field under the rice and wheat rotation field were analyzed, and the different growth phases were discussed. On the basis of the average flux and energy distribution of the lower surface, the effects of the diurnal variation of flux and the temperature and humidity and the wind speed on the distribution of energy are analyzed. Finally, the observation data of the large-aperture scintillator and the vortex-related observation system are compared, and the reliability of the instrument is verified. The main conclusions are as follows: (1) The average flux analysis shows that, during the day, the average sensible heat flux of the wheat return period is the largest, while the average latent heat flux of the rice seedling stage is the largest. The underlying surface still has an upward latent heat flux at night. At the seedling stage and the seedling stage of the wheat, the energy received by the whole underlying surface is less than the sensible and latent heat flux it transfers to the atmosphere. During the whole observation, the average value of H + LE/ Rn was not more than 80%, and the average value of H/ Rn was not more than 18%. (2) The characteristic of daily variation showed that the diurnal variation of the sensible heat flux was very close to that of the lower surface of the wheat, and the average peak of the sensible heat flux was 46.08 Wm-2 during the whole observation period. The analysis of the average daily variation of energy distribution shows that the diurnal variation of the growth cycle, (H + LE)/ Rn and LE/ Rn of the rice is more consistent, and the daily variation trend of the energy distribution is as follows: Stable wave type (heading stage) and gradual growth (maturity stage). The value of H/ Rn in the whole rice growing period is the first and the second, and the maximum value of H/ Rn is about 10:00. The diurnal variation of (H + LE)/ Rn and LE/ Rn was also consistent with the growth of wheat. The diurnal variation of H/ Rn was divided into the first and the second stage (the seedling stage, the overwintering period and the maturity stage) and the steady wave type (the return period and the jointing stage). The diurnal variations of (H + LE)/ Rn, LE/ Rn and H/ Rn are of wave type when the underlying surface is bare. (3) The analysis of the temperature and humidity of the soil and the surface wind speed shows that in the rice planting period, the effect of each variable on the energy distribution is independent, and the energy distribution is mainly affected by the soil moisture and the wind speed. The increase of soil humidity slightly increases the value of H/ Rn, decreases the value of LE/ R, and increases the value of LE/ Rn. During the wheat planting period, the soil temperature and humidity have a common influence on the surface energy distribution. With the increase of soil temperature, the corresponding soil moisture is reduced, and the value of H/ Rn is reduced, and the value of LE/ Rn is increased. During the whole observation period, the diurnal variation of H/ Rn and LE/ Rn is affected by the diurnal variation of the temperature and humidity of the soil and the wind speed, and when the soil temperature is increased, the relative humidity of the soil is reduced, the wind speed is gradually increased and the growth rate is gradually decreased, and the value of LE/ Rn is gradually increased, and the H/ Rn is always stable. (4) The analysis of flux observation data of rice heading period shows that in most cases, the sensible heat flux of LAS is greater than the value observed by EC. Combined with the source region model, it can be found that a mulberry field on the east side of the instrument affects the observation results of the two instruments. As the sensible heat flux above the mulberry field is greater than the sensible heat flux above the rice field. When the mulberry field contributes significantly, the value of the HLAS is always greater than the value of the HEC. The sensible heat flux observed by the two instruments is also close when the contribution of the mulberry garden to the two instruments is consistent. The difference between the two instruments is caused by the non-uniformity of the underlying surface caused by the mulberry garden.
【學位授予單位】：南京信息工程大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：S181
本文編號：2438852
[Abstract]:The heat and latent heat flux is an important part of surface energy balance, and its quantitative understanding is not only the basis of the analysis of the dynamic process of the atmospheric power, but also the core content of the agricultural ecology. The energy exchange characteristics of the atmospheric boundary layer in the middle and lower reaches of the Yangtze River can be better understood in the middle and lower reaches of the Yangtze River. Therefore, on the basis of the flux observation data from July 9,2015 to May 18,2016, the flux change characteristics of the wheat and wheat rotation field under the rice and wheat rotation field were analyzed, and the different growth phases were discussed. On the basis of the average flux and energy distribution of the lower surface, the effects of the diurnal variation of flux and the temperature and humidity and the wind speed on the distribution of energy are analyzed. Finally, the observation data of the large-aperture scintillator and the vortex-related observation system are compared, and the reliability of the instrument is verified. The main conclusions are as follows: (1) The average flux analysis shows that, during the day, the average sensible heat flux of the wheat return period is the largest, while the average latent heat flux of the rice seedling stage is the largest. The underlying surface still has an upward latent heat flux at night. At the seedling stage and the seedling stage of the wheat, the energy received by the whole underlying surface is less than the sensible and latent heat flux it transfers to the atmosphere. During the whole observation, the average value of H + LE/ Rn was not more than 80%, and the average value of H/ Rn was not more than 18%. (2) The characteristic of daily variation showed that the diurnal variation of the sensible heat flux was very close to that of the lower surface of the wheat, and the average peak of the sensible heat flux was 46.08 Wm-2 during the whole observation period. The analysis of the average daily variation of energy distribution shows that the diurnal variation of the growth cycle, (H + LE)/ Rn and LE/ Rn of the rice is more consistent, and the daily variation trend of the energy distribution is as follows: Stable wave type (heading stage) and gradual growth (maturity stage). The value of H/ Rn in the whole rice growing period is the first and the second, and the maximum value of H/ Rn is about 10:00. The diurnal variation of (H + LE)/ Rn and LE/ Rn was also consistent with the growth of wheat. The diurnal variation of H/ Rn was divided into the first and the second stage (the seedling stage, the overwintering period and the maturity stage) and the steady wave type (the return period and the jointing stage). The diurnal variations of (H + LE)/ Rn, LE/ Rn and H/ Rn are of wave type when the underlying surface is bare. (3) The analysis of the temperature and humidity of the soil and the surface wind speed shows that in the rice planting period, the effect of each variable on the energy distribution is independent, and the energy distribution is mainly affected by the soil moisture and the wind speed. The increase of soil humidity slightly increases the value of H/ Rn, decreases the value of LE/ R, and increases the value of LE/ Rn. During the wheat planting period, the soil temperature and humidity have a common influence on the surface energy distribution. With the increase of soil temperature, the corresponding soil moisture is reduced, and the value of H/ Rn is reduced, and the value of LE/ Rn is increased. During the whole observation period, the diurnal variation of H/ Rn and LE/ Rn is affected by the diurnal variation of the temperature and humidity of the soil and the wind speed, and when the soil temperature is increased, the relative humidity of the soil is reduced, the wind speed is gradually increased and the growth rate is gradually decreased, and the value of LE/ Rn is gradually increased, and the H/ Rn is always stable. (4) The analysis of flux observation data of rice heading period shows that in most cases, the sensible heat flux of LAS is greater than the value observed by EC. Combined with the source region model, it can be found that a mulberry field on the east side of the instrument affects the observation results of the two instruments. As the sensible heat flux above the mulberry field is greater than the sensible heat flux above the rice field. When the mulberry field contributes significantly, the value of the HLAS is always greater than the value of the HEC. The sensible heat flux observed by the two instruments is also close when the contribution of the mulberry garden to the two instruments is consistent. The difference between the two instruments is caused by the non-uniformity of the underlying surface caused by the mulberry garden.
【學位授予單位】：南京信息工程大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：S181
【參考文獻】
相關期刊論文 前10條
1 Sang-Hyun LEE;Jun-Ho LEE;Bo-Young KIM;;Estimation of Turbulent Sensible Heat and Momentum Fluxes over a Heterogeneous Urban Area Using a Large Aperture Scintillometer[J];Advances in Atmospheric Sciences;2015年08期
2 郝小翠;張強;岳平;楊澤粟;;黃土高原影響LAS觀測感熱通量的物理因素分析[J];高原氣象;2014年04期
3 郭偉;劉壽東;劉紹民;徐自為;;大孔徑閃爍儀觀測中的相似理論適用性分析[J];高原氣象;2013年04期
4 艾力·買買提明;何清;霍文;劉新春;;塔克拉瑪干沙漠腹地LAS和EC觀測感熱通量對比分析[J];地球科學進展;2010年11期
5 施生錦;黃彬香;劉紹民;楊燕;黃勇彬;徐自為;;大尺度水熱通量觀測系統(tǒng)的研制[J];地球科學進展;2010年11期
6 劉紹民;李小文;施生錦;徐自為;白潔;丁曉萍;賈貞貞;朱明佳;;大尺度地表水熱通量的觀測、分析與應用[J];地球科學進展;2010年11期
7 徐自為;黃勇彬;劉紹民;;大孔徑閃爍儀觀測方法的研究[J];地球科學進展;2010年11期
8 蔡旭暉;朱明佳;劉紹民;徐自為;;大孔徑閃爍儀的通量印痕分析與應用[J];地球科學進展;2010年11期
9 白潔;劉紹民;丁曉萍;盧俐;;大孔徑閃爍儀觀測數(shù)據的處理方法研究[J];地球科學進展;2010年11期
10 朱治林;孫曉敏;賈媛媛;溫學發(fā);張仁華;袁國富;唐新齋;;基于大孔徑閃爍儀(LAS)測定農田顯熱通量的不確定性分析[J];地球科學進展;2010年11期
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