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1.
The use of overhead trellis systems for the production of dry-on-vine (DOV) raisins and table grapes in California is expanding. Studies were conducted from 2006 to 2009 using Thompson Seedless grapevines grown in a weighing lysimeter trained to an overhead arbor trellis and farmed as DOV raisins for the first two years and for use as table grapes thereafter. Maximum canopy coverage for the two lysimeter vines across years was in excess of 80 %. Seasonal (15 March–31 October) evapotranspiration for the lysimeter vines (ETLys) was 952 mm in 2007 (farmed as DOV raisins) and 943 and 952 mm (when farmed as table grapes). The maximum crop coefficient (K cLys) across all 4 years ranged from 1.3 to 1.4. These maximum values were similar to those estimated using the relationship where K c is a function of the amount of shaded area measured beneath the canopy at solar noon (K c = 0.017 × percent shaded area). Covering the lysimeter’s soil surface with plastic (and then removing it) numerous times during the 2009 growing season (1 June–14 September) reduced ETLys from an average of 6.4 to 5.6 mm day?1 and the K c from 1.07 to 0.93. A seasonal basal K c (K cb) was calculated for grapevines using an overhead trellis system with a 13 % reduction in the K cLys across the growing season. 相似文献
2.
Shelly C. Dudley 《Irrigation and Drainage Systems》2009,23(2-3):63-77
This paper will visually show, through the use of historic and contemporary photographs, that the National Reclamation Act is a cornerstone of growth in the West. The irrigation works constructed under the federal reclamation program provided a stable water supply for crops, transforming the desert to the farmlands, and continued with the development of cities, businesses, and communities. Hydropower, a by-product of water development, initially operated irrigation pumps and lighted homes, and now powers industries. Salt River Project (SRP), as one of the first multi-purpose reclamation projects authorized by the federal government, provided irrigation water to the settlers of the Salt River Valley at the beginning of the twentieth century. Over 100 years later, SRP continues that tradition and is still delivering water to its shareholders and customers, but now in an urban setting. 相似文献
3.
Vine water use was measured in a Vitis vinifera cv. Riesling vineyard located in New York. Vines were fully irrigated and were trained via vertical shoot positioning giving
a narrow curtain intercepting about 30% of the incident light during the sunlight hours. Vine water use was estimated on six
vines by sap flow gauges directly calibrated with whole canopy transpiration measurements. The regression analysis between
estimates of transpiration showed that there were large differences between vines in the calibration values obtained. Sap
flow monitoring started late in June, about 2 weeks after bloom, when the canopy already filled the trellis system, and continued
until October. Results showed that vine water use during most of the summer days was between 1.0 and 2.0 mm day−1, with peak values around 2.5 mm. The basal (e.g. vine transpiration/reference evapotranspiration) crop coefficient (K
cb) varied somewhat between days, but it was quite stable during the whole season. Averaged over the entire experimental period,
the K
cb was 0.49. Some of the day-to-day variation in the K
cb was negatively related with daily average air vapour pressure deficit. This suggests that reference evapotranspiration models
on grass may not be fully accurate for vines under these experimental conditions. 相似文献
4.
Jordi Marsal G. Lopez J. del Campo M. Mata A. Arbones J. Girona 《Irrigation Science》2010,28(2):181-189
We examined, over the postharvest seasons of 2005–2007, regulated deficit irrigation (RDI) for its potential of saving water
and maintaining fruit yield and quality in ‘Summit’ sweet cherry. The postharvest irrigation treatments were: full irrigation
(Control), receiving 80% of water in Control (RDI-80%), and receiving 50% of water in Control (RDI-50%). Midday stem water
potential (Ψstem) was used for assessing plant water status. In 2006, trees produced a large crop and commercial fruit thinning had to be
applied, whereas 2007 was a low crop year. The RDI treatment, first applied in 2005, reduced fruit set in 2006 and also reduced
root winter starch concentration. In 2006, fruit set was lower in RDI-50% than in Control. But fruit thinning had still to
be done with the final yield being the same among treatments. In 2007, RDI-50% produced more fruit and higher yields than
Control. Relationship between postharvest Ψstem and crop load in the following season varied according to the year. They were negatively correlated in 2006 and positively
correlated in 2007. Fruit firmness did not vary with irrigation treatments in any of the years. Fruit soluble solid concentration
(SSC) and fruit relative dry matter (RDM) for RDI-50% was the highest in 2006 when RDI-50% trees had the lowest fruit set.
In 2007, SSC and RDM for RDI-50% were the lowest with the trees having the highest fruit set and crop load at harvest. This
study indicates that RDI-50% firstly applied in an “off” year, after crop has been harvested, can maintain fruit yield at
similar levels to fully irrigated trees while saving water by 45%. Correction of biennial bearing and partial saving of thinning
costs are additional advantages of this treatment. 相似文献
5.
Citrus irrigation scheduling is usually based on evapotranspiration (ET) multiplied by a crop coefficient that varies throughout the year. However, ET at 10°C and less has not been investigated. Citrus acclimate to temperatures below 10°C, which affects ET, and therefore may allow irrigation scheduling to be adjusted accordingly. Three separate growth chamber experiments were conducted in complete block design with two temperature treatments and 8-one tree replications with the objective of determining water use of ‘Hamlin’ orange exposed to cold temperatures. The treatments included: full cold-acclimating temperatures, alternating 10 days cold and 3 days warm temperatures, and alternating 10 days warm and 3 days cold temperatures. Although well-watered, trees exposed to temperatures ≤10°C demonstrated lower water use compared to trees held at temperatures that promoted growth. Reduction of water use of cold-treated plants than the controls was 66, 20–57, and 14–28% during full cold-acclimating temperatures, alternating 10 days cold and 3 days warm, and alternating 10 days warm and 3 days cold temperatures, respectively. Reduced water use of cold-treated plants was due to stomatal closure, increased root resistance, and decreased leaf area. Effective irrigation scheduling based on water requirements as they change during cold-acclimating temperatures should save water while providing adequate water for yield and quality. 相似文献
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7s和11s球蛋白分离方法的研究 总被引：2，自引：0，他引：2
大豆蛋白是以低温豆粕为原料,分离提取的大豆分离蛋白、大豆组织蛋白等新型大豆制品,是目前市场上的主导型蛋白产品,其蛋白含量和功能特性各不相同,因而用途也不尽相同。大豆分离蛋白的蛋白质含量高达90%以上,具有良好的乳化性、溶解性、起泡性、吸油性被广泛应用于鱼制品、肉制品、面制品、冷食制品和糖制品中,并且可以改善食品的营养成份和口感,降低成本,延长保质期。为此,主要阐述了大豆7s球蛋白和11s球蛋白的分离富采集方法及其在食品加工中的应用。 相似文献
8.
失眠是一种十分常见的症状,只要在睡觉前做到“四忌”与“四宜”,就可免除失眠之苦。 一忌过饱。晚餐吃得过饱或睡前进餐,一方面会由于上腹饱胀不适而难以入睡,同时也会由于胃肠活动过强而影响大脑皮层的抑制过程,使睡眠不稳、梦多而影响睡眠质量。 相似文献
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当前，农机管理部门在拖拉机驾驶员培训的理论教学方面存在时间短、任务重、重视轻、师资弱等突出问题，致使理论教学成为驾驶员培训最薄弱的环节，如何提高驾驶员的培训质量，成为农机管理部门亟待解决的重要课题。究竟怎样才能搞好拖拉机驾驶员培训的理论教学工作呢？ 相似文献
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福建农机市场’９５回顾与’９６走势省农机公司邓椿祥９５年福建农机市场是意想不到的疲软，农机商品销售量大幅度的下降，经济效益明显地滑波，总体市场是：需求不旺、疲软期长、农机公司的营销状况十分严峻。为了对我省农机市场作出深层次的分析，现将９５年的基本状况... 相似文献
13.
6月817t．江苏省如东县马塘镇亚苏村3组机手阚小林驾驶中拖，来到张笃泉的田头捆麦秆儿。“今天，已经捆了40多亩，一天下来捆个100亩没问题。”阚小林是马塘富民农机服务专业合作社的社员，他说：“这里农户的农灌、机收、机捆、机耕、机插、育秧和植保都是交给我们合作社来完成。” 相似文献
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Analysis of Drought Characteristics and Short-term Prediction in Ji’an Area during 1960―2018北大核心CSCD
【Objective】The purpose of this paper is to further explore the drought condition of Ji’an area in terms of spatial and temporal distribution characteristics, evolution tendency and future situation of drought. 【Method】The result of this paper was concluded based on the different time scale SPI values of precipitation during 1960―2018 among the 13 districts and counties of Ji’an city. The inverse distance weight method was adopted to interpolate the drought frequency. And the spatial distribution characteristics of annual and seasonal drought were analyzed in the research. Moreover, the trends, occurrence timing characteristics, impact range and severity of drought were analyzed by Linear regression method, Mann-Kendall trend test, drought station sub-ratio and run of theory; Precipitation status was also predicted by weighted Markov Model. 【Result】The frequency and range of drought in Ji’an area decreased on the annual scale in terms of the light drought and extreme drought conditions. Droughts in Autumn and winter were more severe because the occurrence frequency was about 30%. However, drought in summer varied greatly on regional distribution. Overall, the spring drought had a tendency to increase in many places; while the summer drought was weakening. The whole basin drought events tended to occur intensively in a short period of time, and the drought area has been reduced obviously in a 20-year cycle, the severity of drought also have been reduced. In conclusion, it was predicted that 6 to 8 regions will be in the low level water condition in 2019 and 2020. 【Conclusion】Ji’an area should focus on drought prevention work in the autumn and winter seasons, and pay attention to the large-scale drought events that may occur in the early 2020s. © 2019 Office of Journal of Irrigation and Drainage, Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences. All rights reserved. 相似文献
16.
有关专家分析1997年的农机产品市场形势时认为,主要农机产品的产销仍将稳中有升,其主要理论依据为: 一是目前我国农村经济正处于建国以来最活跃的时期之一,中央和各级政府都十分重视农业,一再强调必须坚持把农业放在整个经济工作的首位,将继续加大对农业的投入,这将有力 相似文献
17.
李葆武 《中国农村水利水电》1994,(7)
’９４税制改革系列讲座李葆武［编者按］从１９９４年１月１日起，我国全面推行了以流转税制、所得税制为主要内容的工商税制的改革。为了帮助水利水电系统广大干部职工学习新税法、掌握新税法、增强纳税意识、提高政策水平，本刊将根据水利水电系统的情况，陆续刊登税制... 相似文献
18.
María Gómez-del-Campo 《Irrigation Science》2013,31(3):259-269
Maximum production in hedgerow olive orchards is likely not achieved with maximum evapotranspiration over the long term. Thus, regulated deficit irrigation (RDI) should be considered as a management option. Four irrigation treatments were evaluated during the summer, when olive is most drought resistant. Control (CON) was irrigated to maintain the root zone close to field capacity. Severe water deficit was applied by irrigating 30% CON from the end of fruit drop to end July (DI-J) and from end July until beginning of oil synthesis (DI-A). Less severe water deficit was applied during July and August (DI-JA) by irrigating 50% CON. Flowering, fruiting, abscission, fruit development, fresh and dry weight of fruits, and oil production were evaluated. There were not significant differences in number of buds initiated, number of fruits per inflorescence and fruit drop. Oil production was significantly different between irrigation treatments in all experimental years. CON produced more oil and fruit with higher oil % than DI-A and DI-JA. Oil production of DI-J was not significantly reduced compared with CON and oil% was greater. DI-J was the most effective RDI strategy; with 16% less applied water relative to CON. Average loss in oil production of 8% was not significantly different to CON. While DI-JA saved most water (27%), oil production was reduced by 15%. Greatest loss in oil production (21%) was observed in DI-A with water saving of 22%. 相似文献
19.
综合1996、1997两年农用运输车市场走势与发展趋向,预计1998年全国农用车市场将突出表现为以下十大特点。 1.政策驱动。党的十五大和中央经济工作会议确立了国有企业改革的方向,“抓大放小”,对国有企业实施战略资产重组。以资本为纽带,形成有较 相似文献
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今年农机购置补贴你印象最深的是什么？说起这个话题,不同的人可能有不同答案,但具体操作补贴工作的人可能都会发出一声喟叹：“我们可真是战战兢兢如履薄冰啊!” 相似文献