2003，2004，2006和2007年塔里木河下游胡杨光合监测指标数据统计表.主要监测指标：分别测定各叶片的净光合速率( Pn ) 、蒸腾速率( Tr ) 、气孔导度( gs ) 等气体交换参数, 同时测定大气CO2 浓度( Ca ) 、胞间CO2 浓度( Ci ) 、光合有效辐射( Pa r ) 、大气温度( T a ) 、叶面温度( Tl ) 、空气相对湿度( RH) 等参数，每一叶片3 次重复读数。水分利用效率( WUE) = Pn/ Tr , 气孔限制值( Ls )= 1 - Ci / Ca。
", "ds_source": "地下水埋深浅时，胡杨光合作用主要受大气CO2浓度、胞间CO2浓度、光合有效辐射和叶温综合影响，但随着地下水位的下降，大气CO2浓度和光合有效辐射成为限制胡杨光合作用的主因。这是因为低地下水埋深时，地下水供给较充分，叶片不受水分供应限制，当光合有效辐射强时，气温和叶温也相对较高，空气相对湿度小，此时光合和蒸腾都强烈，气孔主要通过提高气孔导度，即减小气孔阻力来适应强烈的蒸腾作用，同时空气中的CO2 也通过开放的气孔源源不断的进入细胞，和胞间的CO2一起成为光合作用的原料，进而造成了空气中和胞间CO2浓度的下降，这即是在光合作用中常造成光合抑制的CO2供应限制。但当受到水分胁迫时，CO2的供应已不是限制光合作用的主要原因，当光合有效辐射增强时，净光合速率、蒸腾速率、气孔导度均增大，在CO2浓度供应还比较充分时，光合作用将因为光合作用所需的另一必须原料——水分的不足而减缓。
", "ds_process_way": "利用L I - 6400 便携式光合作用测定仪使流量为400μmol/ s，并使叶温保持在26°C，利用CO2 注入系统使参比室CO2 浓度保持在360μmol/ mol 或720μmol/ mol，并利用6400 - 02B L ED 光源设定光合有效辐射( PAR) 为2000，1500，1200，1 000，500，300，50，0μmol/ (m2?s) 。每株胡杨分别以东、南、西、北方向中上部挑选健康、成熟叶片12 片，从8 :00 到20 :00，每隔2 h 用光合测定仪Li 6400 (Li 6400，LiCOR，Lincoln，NE，USA)", "ds_quality": "
数据质量优。
", "ds_acq_start_time": "2000-01-19 00:00:00", "ds_acq_end_time": "2007-11-26 00:00:00", "ds_acq_place": "新疆塔里木", "ds_acq_lon_east": 84.25, "ds_acq_lat_south": 40.86666666666667, "ds_acq_lon_west": 85.00611111111111, "ds_acq_lat_north": 41.86666666666667, "ds_acq_alt_low": null, "ds_acq_alt_high": null, "ds_share_type": "login-access", "ds_total_size": 547349, "ds_files_count": 2, "ds_format": "Excel", "ds_space_res": null, "ds_time_res": "日", "ds_coordinate": "WGS84", "ds_projection": "", "ds_thumbnail": "462a5834-99d8-4172-8421-6785b513e379.png", "ds_thumb_from": 0, "ds_ref_way": "", "paper_ref_way": "", "ds_ref_instruction": "None", "ds_from_station": null, "organization_id": "52b7b79b-860c-49a5-9083-9a70cf8bed5a", "ds_serv_man": "敏玉芳", "ds_serv_phone": "0931-4967596", "ds_serv_mail": "ncdc@lzb.ac.cn", "doi_value": "", "subject_codes": [ "170.4510" ], "quality_level": 3, "publish_time": "2021-01-06 10:39:22", "last_updated": "2025-04-23 11:44:19", "protected": false, "protected_to": null, "lang": "zh", "cstr": "11738.11.ncdc.nieer.2020.1526", "i18n": { "en": { "title": "Photosynthetic characteristics of Populus euphratica in the lower reaches of Tarim River from 2000 to 2007", "ds_format": "Excel", "ds_source": "When the depth of groundwater is shallow, the photosynthesis of Populus euphratica is mainly affected by the comprehensive effects of atmospheric CO2 concentration, intercellular CO2 concentration, photosynthetically active radiation, and leaf temperature. However, as the groundwater level decreases, atmospheric CO2 concentration and photosynthetically active radiation become the main factors limiting the photosynthesis of Populus euphratica. This is because when the groundwater in lowlands is buried deep, the groundwater supply is sufficient, and the leaves are not limited by water supply. When the photosynthetically active radiation is strong, the temperature and leaf temperature are relatively high, and the relative humidity of the air is low. At this time, photosynthesis and transpiration are strong, and stomata mainly adapt to strong transpiration by increasing stomatal conductance, that is, reducing stomatal resistance. At the same time, CO2 in the air continuously enters cells through open stomata, and together with CO2 between cells, becomes the raw material for photosynthesis, resulting in a decrease in the concentration of CO2 in the air and between cells. This is the CO2 supply limitation that often causes photosynthesis inhibition in photosynthesis. But when subjected to water stress, the supply of CO2 is no longer the main reason limiting photosynthesis. When the photosynthetically active radiation increases, the net photosynthetic rate, transpiration rate, and stomatal conductance all increase. When the supply of CO2 concentration is still sufficient, photosynthesis will slow down due to insufficient water, another necessary raw material for photosynthesis", "ds_quality": "
Excellent data quality", "ds_ref_way": "", "ds_abstract": "
Main monitoring indicators: net photosynthetic rate (PN), transpiration rate (TR), stomatal conductance (GS) and other gas exchange parameters were measured, At the same time, atmospheric CO2 concentration (CA), intercellular CO2 concentration (CI), photosynthetically active radiation (PAR), atmospheric temperature (TA), leaf surface temperature (TL), air relative humidity (RH) and other parameters were measured, and each leaf was read three times. WUE = pN / TR, LS = 1 - CI / ca.
", "ds_time_res": "日", "ds_acq_place": "Tarim, Xinjiang", "ds_space_res": "", "ds_projection": "", "ds_process_way": "Use the LI-6400 portable photosynthesis analyzer to maintain a flow rate of 400 μ mol/s and a leaf temperature of 26 ° C. Use a CO2 injection system to maintain a CO2 concentration of 360 μ mol/mol or 720 μ mol/mol in the reference chamber, and set the photosynthetically active radiation (PAR) to 2000, 1500, 1200, 1000, 500, 300, 50, 0 μ mol/(m2? S) using the 6400-02B LED light source. Select 12 healthy and mature leaves from each Populus euphratica plant towards the upper and middle parts in the east, south, west, and north directions. From 8:00 to 20:00, use a photosynthesis analyzer Li 6400 (Li 6400, LiCOR, Lincoln, NE, USA) every 2 hours", "ds_ref_instruction": "None" } }, "submit_center_id": "ncdc", "data_level": 0, "license_type": "https://creativecommons.org/licenses/by/4.0/", "doi_reg_from": "reg_local", "cstr_reg_from": "reg_local", "doi_not_reg_reason": null, "cstr_not_reg_reason": null, "is_paper_in_submitting": false, "ds_topic_tags": [ "空气相对湿度", "大气温度", "co2浓度", "光合作用", "胡杨", "光合有效辐射", "气孔导度", "净光合速率", "蒸腾速率", "页面温度" ], "ds_subject_tags": [ "自然地理学" ], "ds_class_tags": [], "ds_locus_tags": [ "新疆塔里木下游" ], "ds_time_tags": [ 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 ], "ds_contributors": [ { "true_name": "陈亚宁", "email": "chenyn@ms.xjb.ac.cn", "work_for": "中国科学院新疆生态与地理研究所", "country": "中国" } ], "ds_meta_authors": [ { "true_name": "陈亚宁", "email": "chenyn@ms.xjb.ac.cn", "work_for": "中国科学院新疆生态与地理研究所", "country": "中国" } ], "ds_managers": [ { "true_name": "陈亚宁", "email": "chenyn@ms.xjb.ac.cn", "work_for": "中国科学院新疆生态与地理研究所", "country": "中国" } ], "category": "生态" }