Roof Vegetation: Sedum
Four-Component Radiometer
Indoor Thermal Couple Meteorological Station
12
Vegetated Roof in Beijing Urban Area
(Beijing site, 2009.06~)
(1) Instruments: Meteorological system, eddy covariance system, soil profiles, crop growth status, leaf-level gas exchange, water quality. (2) Observation Items: a. wind speed/direction, air temperature/humidity, air pressure, surface temperature, precipitation, radiation; b. Latent/sensible heat flux, soil heat flux, carbon dioxide flux, soil evaporation, soil respiration; c. Stomatal conductance, photosynthesis rate, transpiration; d. Soil temperature, soil moisture, soil water potential, groundwater table; e. Leaf area index, dry biomass, crop yield; f. N-NO3 and N-NH4 concentrations in groundwater and soil water Photosynthesis rate
15
Oasis vegetation in the Northwest of China
(Korle site, 2007.09~)
(1) Instruments: Meteorological system, soil profiles, eddy covariance system(under construction) (2) Observation Items: a. wind speed/direction, air temperature/relative humidity, air pressure, surface temperature, precipitation, radiation; b. Latent/sensible heat flux, soil heat flux, carbon dioxide flux (under construction); c. Soil salinity, soil temperature, soil moisture, water table depth; d. Crop growing Cotton field
研究生专题讲座，2012.05.21
流域生态水文过程观测与模拟
楊大文 (yangdw@) 清华大学水利系
报告提纲
一、生态水文学的背景 二、生态水文过程观测及机理分析 三、生态水文模型构建及验证 四、气候变化的生态水文响应分析 五、生态水文学的研究思路
2
全球淡水仅占总水量的2.5% 而淡水中仅三分之一可以为人类利用
陕西榆林生态水文观测站位置
观测塔和涡度相关系统
2010年开始建设，2011年 6月正式开始连续观测。
榆林生态水文观测站下垫面情况
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陕西榆林自然流域水文过程观测
榆林生态水文过程的初步观测结果
地表能量通量变化过程
沙柳（28.2%）
沙蒿（27.9%）
不同深度土壤体积含水率、温度、水势变化
主要植物覆盖度调查结果
蓝水：径流 （可再利用） （不能再利用）
气候变化的流域生态水文响应研究是水文学的前沿和热点
流域生态与水文过程之间存在着复杂的相互 作用，气候是二者的主要驱动力之一； 气候变化下的流域水资源变化，要求我们必 修研究生态过程与水文过程的耦合作用。
水文 过程 生态 过程
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气候 变化
二、生态水文过程观测及机理分析
3
世界人口变化和预测
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粮食生产需要大量水资源
5
人口增长导致水资源危机
全球缺水人口：5亿
40亿
全球人口：60亿
89亿
6
一、研究背景
水循环是一切水问题的科学基础，生态与水文过程相互作用是 流域水循环的关键环节 绿水：蒸散发
流域水循环决定水资源，影响生态系统； 粮食生产和植被生态维持是水的主要社会与生 态服务功能，也是“绿水”的主要消耗方式； 人类活动（如灌溉和水土保持等）直接影响生 态、水文及水资源。
(3) Observation results
50 GA 45 40 35 30 25 20 00 :00 02 :00 04 :00 06 :00 08:00 10:00 12 :00 14 :00 16 :00 18 :00 20 :00 22 :00 00:00 MT MB GRS CRS
Overall Runoff Retention
Long-term variability of CO2 flux
N-NO3
TN
N-NH4
Long-term variability of N concentration
11
Vegetated Roof in Beijing Urban Area
(Beijing site, 2009.06~)
(1) Instruments: Meteorological system, soil profiles, runoff flowmeter. (2) Observation Items: a. wind speed/direction, air temperature/humidity, air pressure, surface temperature, precipitation, radiation; b. Soil temperature, soil moisture, soil water potential; c. Precipitation, runoff d. Indoor surface and air temperature;
6 5 4 3 2 1 0 12:00
Rain : 80.8 mm Runoff : 44.9 mm Rtn. Ratio: 44.4
4
2
0 20:00
Temperature °C
Time
variability of roof surface temperature on a typical summer day
20110716
8
20110724
7
Intensity mm 5min
Intensity m m 5min
6
Rain : 61.0 mm Runoff : 12.5 mm Rtn. Ratio: 79.5
0 20 ) m 40 c ( h t 60 p e 80 d l i 100 o s120 140 0.2 0.4 0.6 0.8 1
M
The influential indices of mulched drip irrigation on soil salt
The soil water and salinity at the period of spring sowing (April 15th) under different non-growth flush styles 17
Eco-hydrologic Observations in the Water-limited Region
Mean PPT: 59 mm Mean Ta: 11.5 oC Vegetation: cotton Mean PPT: 399 mm Mean Ta: 8.4 oC Vegetation: sparse shrub & grass Mean PPT: 389 mm Mean Ta: 6.6 oC Vegetation: grassshrubdesert
Soil respiration
Soil profile
Flux tower 10
Plain cropland along the Downstream of Yellow River
(Weishan site, 2005.03~)
(3) Observation results
Long-term variability of ET
Soil profile
Laboratory
16
Oasis vegetation in the Northwest of China
(Korle site, 2007.09~)
(3) Observation results
The cotton yield and water utilization efficiency under different treatments
Mean PPT.: 534 mm Mean Ta: 13.8 oC Vegetat研 究所建设和维护 9
Plain cropland along the Downstream of Yellow River
(Weishan site, 2005.03~)
Agro-pastoral transitional zone in the Northeast of China
(Tongliao site, 2012~)
(1) Instruments: Meteorological sites, two eddy covariance systems (one for grazed meadow, another for desert), soil profiles, LAS (Large Aperture Scintillometer). (2) Observation Items: a. wind speed/direction, air temperature/relative humidity, air pressure, surface temperature, precipitation, radiation; b. Latent/sensible heat flux, soil heat flux, carbon dioxide flux; c. Soil temperature, soil moisture, soil water potential, water table depth; d. Leaf area index. Cropland