2009-2016年中国农业大学石羊河实验站玉米日耗水量数据集

掌握农田系统作物耗水量变化情况,对研究作物各生育期水分消耗规律至关重要。基于此,本数据提供了中国农业大学石羊河实验站内大型称重式蒸渗仪实测的玉米耗水量数据,时间分辨率为日尺度,灌溉方式为畦灌,数据范围为2009–2016年。数据采集和处理过程严格遵循仪器数据质量控制和规范。数据以日为尺度公开,以期为区域农业水资源高效利用提供依据。

结合信息熵和模糊优选的种植结构优化模型

种植结构优化是区域灌溉用水管理关键环节。文章提出一个结合信息熵和模糊优选的种植结构多目标优化模型(E-FOS-MOP)。信息熵引入合理界定多目标之间相对重要性,模糊优选理论引入有效处理多目标非线性问题。将信息熵方法与模糊优选理论相结合,整合到传统多目标规划模型框架中,应用于西北地区武威市凉州区种植结构规划问题,获得不同节水灌溉水平条件下种植结构优化方案。结果表明,在保障粮食安全情况下压缩小麦、玉米等粮食作物种植面积,同时推广蔬菜、瓜类等经济作物,可有效提高经济效益和综合水分生产力。E-FOS-MOP模型优于传统多目标规划模型(MOLP)和基于模糊优选的模型(FOS-MOP)。相比于现状种植结构,由E-FOS-MOP模型优化得到的效益和水分生产力均有较大提高,总耗水大幅缩减。该模型及其优化结果可为区域水资源管理提供参考。

不同水盐胁迫对番茄生长发育和产量的影响研究

【目的】探究番茄植株对不同水盐胁迫情景的响应,为合理制定盐碱化土壤下的灌溉制度提供科学依据。【方法】以粉欧宝番茄品种为研究对象,开展水盐对番茄生长发育影响的盆栽试验。试验采用完全随机布置,设置3个水分水平(W1-充分灌溉、W2-1/2的W1灌水量、W3-干旱复水)和2个盐分水平(S1-无盐和S2-0.3%含盐量),每个处理4个重复,测定了番茄耗水、干物质和产量指标,分析了不同水盐胁迫对番茄植株生长发育与产量的影响。【结果】与充分灌溉W1相比,W2水平的番茄植株耗水、干物质、植株含水率、叶质量、产量、单果质量显著减少。W3水平的植株耗水量和叶茎比显著减少,但单株干质量与鲜干比所受影响不大;单果鲜质量与干质量显著减小,但坐果率提高导致产量有所增加。盐分处理的番茄植株耗水量、单株干质量、鲜干比、叶茎比、果实总产量、单果鲜质量与干质量均小于无盐处理。水分胁迫显著影响叶片生长和单个果实发育,盐分胁迫抑制植株的生长发育及产量形成。【结论】干旱复水与无盐处理组合(W3S1)下番茄植株表现出了较好的生长发育状况和产量水平,可用于最优调亏灌溉制度的制定。

Time lag characteristics of sap flow in seed-maize and their implications for modeling transpiration in an arid region of Northwest China

Plant capacity for water storage leads to time lags between basal stem sap flow and transpiration in various woody plants. Internal water storage depends on the sizes of woody plants. However, the changes and its influencing factors in time lags of basal stem flow during the development of herbaceous plants including crops remain unclear. A field experiment was conducted in an arid region of Northwest China to examine the time lag characteristics of sap flow in seed-maize and to calibrate the transpiration modeling. Cross-correlation analysis was used to estimate the time lags between stem sap flow and meteorological driving factors including solar radiation（R_s） and vapor pressure deficit of the air（VPD_（air））. Results indicate that the changes in seed-maize stem sap flow consistently lagged behind the changes in R_s and preceded the changes in VPD_（air） both on hourly and daily scales, suggesting that light-mediated stomatal closures drove sap flow responses. The time lag in the maize＇s sap flow differed significantly during different growth stages and the difference was potentially due to developmental changes in capacitance tissue and/or xylem during ontogenesis. The time lags between stem sap flow and R_s in both female plants and male plants corresponded to plant use of stored water and were independent of total plant water use. Time lags of sap flow were always longer in male plants than in female plants. Theoretically, dry soil may decrease the speed by which sap flow adjusts ahead of shifts in VPD_（air） in comparison with wet soil and also increase the speed by which sap flow adjusts to R_s. However, sap flow lags that were associated with R_s before irrigation and after irrigation in female plants did not shift. Time series analysis method provided better results for simulating seed-maize sap flow with advantages of allowing for fewer variables to be included. This approach would be helpful in improving the accuracy of estimation for canopy transpiration and conductance using meteorological measurements.

Responses of water productivity to irrigation and N supply for hybrid maize seed production in an arid region of Northwest China

Water and nitrogen（N） are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield（WP_（Y-ET）） and final biomass（WP_（B-ET）） of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels（70%–65%, 60%–55%, and 50%–45% of the field capacity） combined with three N rates（500, 400, and 300 kg N/hm^2） were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm^2 in 2014. Results showed that the responses of WP_（Y-ET） and WP_（B-ET） to different irrigation amounts were different. WP_（Y-ET） was significantly reduced by lowering irrigation amounts while WP_（B-ET） stayed relatively insensitive to irrigation amounts. However, WP_（Y-ET） and WP_（B-ET） behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm^2 on the WP_（Y-ET） and WP_（B-ET）, however, when reducing N input to 100 kg/hm^2, the values of WP_（Y-ET） and WP_（B-ET） were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield（Y） and final biomass（B）. Partial factor productivity from applied N（PFP_N） was the maximum under the higher irrigation level and in lower N rate（100–300 kg N/hm^2） in both years（2013 and 2014）. Lowering the irrigation amount significantly reduced evapotranspiration（ET）, but ET did not vary with different N rates（100–500 kg N/hm^2）. Both Y and B had robust linear relationships with ET, but the correlation between B and ET（R^2=0.8588） was much better than that between Y and ET（R^2=0.6062）. When ET increased, WP_（Y-ET） linearly increased and WP_（B-ET） decreased. Taking the indices of Y, B, WP_（Y-ET）, WP_（B-ET） and PFP_N into account, a higher irrigation level（70%–65% of the field capacity） and a lower N rate（100–300 kg N/hm^2） are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China.

集成萌芽期生长和苗期生理指标高通鉴选番茄耐盐品种

确定最优耐盐指标并鉴选耐盐番茄品种对提高盐碱地作物用水效率至关重要,但集成萌芽期生长和苗期生理指标高通鉴选耐盐品种的研究还较少。本文选用10个不同番茄品种,分别在萌芽期和苗期设置了4个盐分水平(0、50、100、150 mmol·L^(-1)盐水灌溉,S1~S4)。测定了萌芽期芽长、根长、鲜重和干重,计算了发芽势、发芽率和发芽指数;苗期气孔导度、叶水势、叶绿素、株高、茎粗、地上鲜重和干重。结果表明,耐盐品种在受到盐分胁迫后,发芽指数和芽长、气孔导度和叶水势变化幅度较小。因此,它们可以分别作为萌芽期和苗期耐盐指标。通过对集成萌芽期生长和苗期生理指标鉴选得出‘京丹8号’是10个番茄品种中最耐盐的品种。总之,本文提出的集成萌芽期和苗期耐盐性评价方法,具有周期短、准确性高的特点,可用于耐盐品种的高通鉴选。