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1.
The drought in spring leads to the lack of soil water, which influents sprout and bud of crops, which furthermore affects growth and yield of crops. Studying the technology integration of bed-irrigating sowing, the mending irrigation of seedling stage and the effect of water-saving of ridge plotted field, analyzing the finger of yield and dry matter accumulation, water-saving technology integration have good effects on water-saving, water storage and increasing moisture on soil and enhancement of soybean yield.  相似文献   

2.
Irrigation water became the limiting factor to the persistent improvement of grain production. Based on the data from Gannan County, a semiarid area in the west of Heilongjiang Province, the present situation of the development and utilization of water resources and the suitable water saving irrigation mode were analyzed by using SPA model, which was significant to the efficient and rational utilization of water resources and the improvement of agriculture productivity. The result showed that the model could be applied well to the assessment of development and utilization of water resources and the multi-project optimal selection. Through calculation, it could be found that the utilization of water resources in Gannan County was still in the primary stage, and the integration technology of the optimized water saving irrigation should be combined to support the sustainable development of agriculture in the semiarid area.  相似文献   

3.
Based on the data for meteorology, hydrology, soil, planting, vegetation, and socio-economic development of the irrigation region in the middle reaches of the Heihe River basin, Northwest China, the model of balance of water supply and demand in the region was established, and the security of water resource was assessed, from which the results that the effects of unified management of water resources in the Heihe River basin between Gansu Province and Inner Mongolia on regional hydrology are significant with a decrease in water supply diverted from Heihe River and an increase in groundwater extracted. In addition, it was found that the groundwater level has been steadily decreasing due to over pumping and decrease in recharges. In present year (2003), the volume of potential groundwater in the irrigation districts is far small because of the groundwater overdraft; even in the particular regions, there is no availability of groundwater resources for use. By 2003, water supply is not sufficient to meet the water demand in the different irrigation districts, the sustainable development and utilization of water resources are not secured, and the water supply crisis occurs in Pingchuan irrigation district. Achieving water security for the sustainable development of society, agriculture, economy, industry, and livelihoods while maintaining or improving the abilities of the management and planning of water resources, determining of the reasonable percentage between water supply and groundwater utilization and water saving in agricultural irrigation are taken into account. If this does not occur, it is feared that the present performance of water development and planning may further aggravate the problem of scarcities of water resources and further damage the fragile ecological system.  相似文献   

4.
Advances and Developing Tendency of Water Use Efficiency in Plant Biology   总被引:1,自引:0,他引:1  
Biological water saving is one of the major fields of water saving agriculture in the future and has an enormous potential in agricultural production. In this paper, the necessity and urgency of developing high water use efficiency in plant biology were dissertated firstly, and the research progresses at home and abroad were reviewed as following aspects: mechanisms of drought resistance and high water use efficiency, criterions for identifying and evaluating drought resistance and water use efficiency, genetic improvement for drought resistance and water use efficiency, water saving irrigation technology based on the physiological regulation and control in crop plants. Major problems in the research field at present were put forward, and development tendency of water use efficiency in plant biology in the future were also discussed.  相似文献   

5.
Soil water is strongly affected by land use/cover in the Loess Plateau in China. Water stored in thick loessal soils is one of the most important resources regulating vegetation growth. However, soil water in the deep loess proifle, which is critical for maintaining the function of the“soil water pool”is rarely studied because deep proifle soil samples are dififcult to collect. In this study, four experimental plots were established in 2005 to represent different farming systems on the Changwu Tableland:fallow land, fertilized cropland, unfertilized cropland, and continuous alfalfa. The soil water content in the 15-m-deep loess proifles was monitored continuously from 2007 to 2012 with the neutron probe technique. The results showed that temporal variations in soil water proifles differed among the four farming systems. Under fallow land, the soil water content increased gradually over time, ifrst in the surface layers and later in the deep soil layers. In contrast, the soil water content decreased gradually under continuous alfalfa. The distributions of soil water in deep soil layers under both fertilized and unfertilized cropland were relatively stable over time. Thus farming system signiifcantly affected soil water content. Seven years after the start of the experiment, the soil water contents in the 15-m-deep proifles averaged 23.4%under fallow land, 20.3%under fertilized cropland, 21.6%under unfertilized cropland, and 16.0%under continuous alfalfa. Compared to measurements at the start of the experiment, both fallow land and unfertilized cropland increased soil water storage in the 15-m loess proifles. In contrast, continuous alfalfa reduced soil water storage. Fertilized cropland has no signiifcant effect on soil water storage. These results suggest that deep soil water can be replenished under the fallow and unfertilized farming systems. Dry soil layers (i.e., those which have soil water content less than the stable ifeld water capacity) in the subsoil of the Changwu Tableland region can be classiifed as either temporary dry soil layers or persistent dry soil layers. Temporary dry soil layers, which typically form under annual crops, often disappear during wet years. Persistent dry soil layers generally develop under perennial vegetation. Even after removing the vegetation, persistent dry soil layers remain for several decades. This study provides information useful for the conservation and utilization of soil water resources in the Loess Tableland.  相似文献   

6.
Based on the theory of complex adaptive system(CAS), the optimal allocation model of water resources in sewage irrigation areas was established, which provided new ideas and application value for the rational utilization of agricultural production and waste water resources.The results demonstrated that the difference of crop energy capture mainly depended on the development stage.Waste water with a certain concentration was able to promote crop growth, while excessive concentration inhibited crop growth.The correlation between water absorption rate and leaf area index was close(R=0.9498, p0.01).The amount of bad seeds increased at a speed of 34.7 · d~(-1), when system irrigated randomly in the seedling stage, while it tended to remain stable at a speed of 0.3 · d~(-1) after plants entering the mature stage which impacted the total yields of crops.  相似文献   

7.
The North China Plain (NCP), one of the most important agricultural regions in China, is facing a major water-resource crisis evoked by excessive exploitation of groundwater. To reduce water use while maintaining high crop production level, improving variety water use efficiency (WUE) is an urgent need, especially because other water-saving measures such as water delivery, irrigation, and agricultural practices have already achieved most possible progresses. Evaluation of variety WUE can be performed accurately at the individual plant level (WUEp). Reviewing the studies on physiological factors affecting WUE p performed up to date, stomatal conductance was considered to be an important trait associating closely with WUE p . The trait showed a large degree of varietal variability under well-watered conditions. Crop varieties differ highly in sensitivity of stomata to soil and air drying, with some varieties strongly reducing their stomatal conductance in contrast with those lightly regulating their stomata. As a result, difference among varieties in WUE p was enlarged under water deficit conditions in contrast with those under well-watered conditions. The relationship between stomatal conductance and yield depends on water availability of whole growing period in local areas. Usually, large stomatal conductance results in a high yield under good irrigation system, whereas a low stomatal conductance can lead to yield benefit under limited stored soil moisture conditions. In the NCP, winter wheat is the largest consumer of irrigation water, improvement strategies for high WUE aiming at wheat crops are in urgent need. We suggest, for the well-irrigated areas with excessive exploitation of groundwater, the wheat breeding program need to combine medium stomatal conductance (0.35 mmol H2O m-2 s-1 or so), high carboxylation efficiency, and high harvest index. Areas with partial/full access to irrigation, or infrequent drought, should target wheat varieties with high stomatal conductance under no water stress and low sensitivity of stomata to soil water deficit. Drought-prone rain-fed areas characterized by frequent and long terminal drought should target wheat varieties with low stomatal conductance under no water stress and high stomata sensitivity to soil drying to make water available during grain filling.  相似文献   

8.
Water shortage is increasingly an important factor limiting the sustainable development of global economy, posing a huge threat to social security and human existence. Water usage in agriculture accounts for about 70% of total water consumption in the world, and rice cultivation is in turn the largest water user, which accounts for about 50% of total water usage in agriculture. Therefore, it is quite important to improve water utilization efficiency to reduce water consumption in rice. Water stress causes severe inhibition of plant growth and development as well as yield reduction, however the extent of inhibition or reduction varies greatly with the growth stages, duration and severity of stress, and plant genotypes. In rice, drought resistance and water utilization efficiency might be improved by developing stress resistant cultivars and conducting proper agronomic practices. It is hence imperative to determine the suitable criteria in morphological and physiological traits for drought resistance and water utilization efficiency in conventional breeding of rice. At present, leaf rolling, leaf water potential and carbon isotope discrimination are commonly used criteria for the evaluation and identification of germplasm with high drought resistance or water utilization efficiency. With rapid development of molecular biology, marker-assisted selection has been used in rice breeding against water stress. In this review, therefore, the agronomic aspect of water saving techniques such as selection of suitable rice cultivars, planting pattern, mulching, deficit irrigation and alternative drying and moist irrigation are discussed and effective approaches are also recommended.  相似文献   

9.
《农业科学与技术》2013,(10):1486-1490,1494
[Objective] This study aimed to investigate the optimal technology for en- zymolysis of jeUyfish brain protein by bromefain. [Method] Effects of enzymolysis temperature, the amount of added enzyme, solid/liquid ratio, enzymolysis time and pH on the enzymolysis of total protein were investigated through single factor ex- periments, and some technical parameters were optimized by orthogonal experi- ments. [Result] The results revealed that enzymolysis temperature of 55℃, the amount of added enzyme of 4 000 U/g, solid/liquid ratio of 1:4, the amount of added enzyme time for 5 h and pH 7 were the optimal combination of parameters for the enzymolysis; the average degree of hydrolysis obtained from the verification tests was 36.9%, indicating that the optimized results of the orthogonal experiment were credible. [Conclusion] This study provides the optimized conditions reliable theo- retical foundation and technical support for the exploitation and utilization of jellyfish resources as medicines or functional food in China.  相似文献   

10.
M.  I.  AI-Saud 《农业科学与技术》2010,(5):112-120
Saudi Arabia has achieved extensive development and expansion in agriculture sector and achieved self sufficiency in a number of agricultural crops including wheat, fodders, dates, some vegetables and fruits. Considering the future growing need for food and water, government of Saudi Arabia has formulated and implemented a number of policy reforms for conservation, optimal utilization and sustainable development of natural resources of the Kingdom. The present study focuses on potential future impacts on natural resources conservations and strategic planning due to recent policy reforms (Council of Ministers (CoM) on Water Resources Management and Conservation (Decision No. 335)) issued on September 2008. The modeling of wheat agriculture was performed based on detailed analysis of water application practices in wheat growing regions/districts and future projection of wheat irrigation in context of recent government water resources conservation strategy. The results clearly indicated a significant positive impact will be occurred in terms of huge relief on highly stressed and limited national strategic groundwater resources. The present study estimated a saving and conservation of more than 51.0 billion cubic meters (BCM) of non-renewable groundwater resources during next 11 years.  相似文献   

11.
《河北农业大学学报》创刊年代考   总被引:3,自引:0,他引:3  
清光绪二十八年(1902)河北农业大学前身—直隶农务学堂诞生,经几易其名,于1958年更名为河北农业大学至今。清光绪三十一年(1905)直隶高等农业学堂时期创办了《北直农话报》,清光绪三十四年(1908)更名为《直隶农务官报》,中华民国七年(1918)改出《农学月刊》,中华民国十七年(1928)易名为《河大农刊》,中华民国二十三年(1934)更名为《河北通俗农刊》,中华民国二十四年(1935)易名为《河北农林学刊》,1948年更名为《河北农学院研究专刊》,1959年更名为《河北农业大学学报》至今。《河北农业大学学报》前身诸刊都与现时的《河北农业大学学报》有着一脉相承的历史渊源,各刊之间联系紧密,连续性、继承性强。因此,《河北农业大学学报》的创刊时间应追溯至1905年创办的《北直农话报》。  相似文献   

12.
为探明客源市场生态旅游消费的潜在特征,采用问卷调查的形式,就长沙市居民对湖南金洞生态旅游开发的意向等问题进行抽样调查.结果显示,生态旅游符合人们“回归自然”的旅游新时尚,有着极大的开发空间,指出生态旅游的开发要注重环境保护和可持续发展.开发的产品要以休闲度假类的大众产品为主,开发生态旅游都市客源市场还要多种渠道并用,尤其是要注重媒体的宣传.  相似文献   

13.
饲料中有效能是供动物生长发育的基础.不同动物所用的有效能体系不同,目前大多数动物采用消化能、代谢能体系,但随着研究的发展与深入,发现最能反映饲料有效能的是净能体系.无论哪种体系,采用合理的测定技术准确测定饲料中的有效能值显得尤其重要,通过对饲料有效能值的准确测定可以实现动物所需能量的精确供给,减少养殖成本,使经济效益最大化.文章综述了几种有效能评价体系的测定技术.  相似文献   

14.
国家贫困生资助政策实施以来,对贫困生帮助很大,同时在实际运行中还存在着一些问题。本文提出贫困生认定工作仍需要进一步采取各种相关配套措施,以推动和保障贫困生资助工作更好地开展。  相似文献   

15.
应用萄聚糖凝胶柱层析对水牛梭形住肉孢子虫包囊包溶性抗原进行了纯化。结果表明:纯化水牛梭形住肉孢子虫包囊抗原的最适条件为:选用萄聚糖凝胶G—100柱层析系统;洗脱液为03MPBS(pH72),床体积为10cm×165cm,上样体积为500HL;流速为12mL/h。纯化抗原可使琼脂凝胶双扩散试验的阳性检出率提高30%。  相似文献   

16.
[目的]通过体外抗氧化体系比较黑豆不同部分馏油抗氧化性活性。[方法]通过正交试验优化索氏提取黑豆馏油的最佳工艺,提取黑豆不同部分馏油;研究黑豆不同部分馏油对羟基自由基(·OH)、DPPH自由基(DPPH·)的清除能力。[结果]在样品浓度为1.0 mg/mL时,黑豆不同部分馏油对·OH的清除率分别为全豆馏油83.9%、豆黄(黑豆去皮部分)馏油64.8%、豆皮馏油17.3%,对DPPH·的清除率分别为全豆馏油41.3%、豆黄馏油33.2%、豆皮馏油77.9%。[结论]黑豆不同部分馏油均具有较好的抗氧化性,是良好的天然抗氧化剂。黑豆不同部分馏油对·OH的清除能力从大到小依次为全豆馏油、豆黄馏油、豆皮馏油,对DPPH·的清除能力从大到小依次为豆皮馏油、全豆馏油、豆黄馏油。  相似文献   

17.
采用L(934)正交设计试验,对山茱萸浸提液中山茱萸多糖的酶水解法提取工艺进行了优化研究,并对浸提液的中有效成分马钱苷含量进行了HPLC法分析。结果表明,山茱萸多糖浸提的最佳工艺为:液料比1∶5,浸提时间4 h,浸提温度80℃,果胶酶添加量0.55 g/L。用HPLC法测定出的山茱萸浸提液中马钱苷平均含量为0.512 ...  相似文献   

18.
板栗属壳斗科栗属(Castanea mollisima Blume),其种子属于顽拗型种子,不耐贮藏。基于近年来板栗贮藏保鲜技术研究成果,从合理采收、贮前处理、贮藏方法等方面进行论述。  相似文献   

19.
为了预测厚胶合板弹性模量,通过简化层合板理论,该文建立了胶合板弹性模量预测模型,并以单板条、经过涂胶热压处理的单板条和相同工艺条件下的单板层积材的弹性模量,采用4种不同铺层方式的19层桉树胶合板对模型进行了验证。结果表明:3种预测值与实测值的趋势一致,相关系数R2顺纹在0.86以上,横纹在0.88以上,但是精度不同。采用单板条弹性模量预测的胶合板弹性模量比实测值偏低;采用经过涂胶热压处理后的单板条弹性模量预测的胶合板弹性模量比实测值偏高;采用相同工艺条件下的单板层积材弹性模量预测的胶合板弹性模量与实测值偏差较小,顺纹平均误差为4.64%,横纹平均误差10.94%。因此,采用相同工艺条件下的单板层积材的弹性模量来预测胶合板的弹性模量是可行的。   相似文献   

20.
赵经华  张春姹 《安徽农业科学》2006,34(17):4480-4481
分析了入世4年来,我国水果出口在量上实现了突破,但并没有实现质变的主要原因,指出我国水果业存在的问题。论述了引进外资对发展我国水果业的意义,并提出了具体可行的对策与建议。  相似文献   

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