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1.
The Plaichumpol Irrigation Project, in Nan Basin of Thailand, is selected as a case study of impact study, where farmers depended on both surface and groundwater sources (especially in the dry year), to assess the impact on irrigation systems. The study used the MRI-GCM data to project the future climate condition and assess the impact on irrigation systems focusing on water shortage and groundwater pumping aspects in the selected consecutive dry years. The responses from farmers on the impact and adaptation were also gathered via site interviews and analyzed. Based on the bias-corrected MRI-GCM data, the annual rainfall in Nan Basin will decrease in the near future (2015–2039), compared with the past average data (1979–2006), while the rainfall will increase in the far future (2075–2099) compared with past. Water supply from dam will decrease in wet season and dry season, while water demand in both of near future and far future will increase in wet season and dry season. Less water shortage and groundwater pumping in both near-future and far-future periods are expected in the future consecutive dry years compared with the past, though the groundwater is still an important supplementary irrigation water source in the dry year. From the field interview, the farmers are ready to adapt to the changing situations and join in the water use meeting to follow up with irrigation officers about the adjustment of plant calendar and water allocation due to the climate change and to prepare adaptation measures as necessary.  相似文献   

2.
Irrigation projects with reservoirs have contributed to the stabilization of traditional rainfed rice and to the introduction of double-rice in monsoon Asia. This type of irrigation also has the capability of shifting the traditional rice-cropping season. This paper discusses the influences of the shifted cropping season on water resources and the effective use of the reservoir in the Ngamoeyeik Irrigation Project Area in Lower Myanmar. Synthesized streamflow data were applied to simulate water storage in the reservoir. The main results are as follows: (1) shifting the cropping season to avoid inundation problems can increase water availability, (2) the amount of evaporation loss in the reservoir water budget can be as high as 16%, which decreases water efficiency in the reservoir operation during the dry season, (3) a shifted cropping season is preferable under the special hydrological conditions found in Lower Myanmar.  相似文献   

3.
Egypt faces great challenges due to its limited water resources by enforcement policies to improve the performance of the existing delivery system and its development. The improvement of irrigation systems in the Nile Delta is one of the most important attempts in Egypt to implement more effective irrigation technologies. This study was carried out to evaluate improved tertiary canal level and farmers’ practices by comparing with other unimproved systems to understand the farmers’ practices in their farms after modifying the existing irrigation system. This study area applied to the Wasat command area’s most commonly used to the cultivation of a paddy field in Egypt, which contributes 40 % of production. The overall results indicate that the water-use application at the improved system level improved. This was due to the role of water user association in the successful management and operation of the water-supply system on the private level of water distribution network. So, water users’ association has the positive effect on managing of the improved tertiary canal. Although, there are main problems of water delivery in the irrigation networks that was a water shortage in the main canal owing to its location at the tail of the feeder canal system in the Nile Delta, and other reasons include the absence of crop production planning by farmers, especially rice farmers in summer, and the greater demand of some fields than supply.  相似文献   

4.
System of rice intensification (SRI) has been disseminated in many countries because of its high yield, although the mechanism of yield increase has yet to be fully understood. The aims of this study were to clarify the actual water management of a skilled SRI farmer in irrigated paddy field of Indonesia and to examine the effect of intermittent water management on rice growth and yield. Yield and yield components were compared in the field experiments in the farmer’s fields under intermittent (SRI) or flooded (FL) irrigation for 4 years from 2013 to 2016. The daily mean water depth of SRI plots during 0–40 days after transplanting showed very shallow (ca. 2 cm) or little lower than soil surface and continued to be lower than soil surface during reproductive stage when panicles were formed. The yield of SRI significantly exceeded that of FL for 4 years by 13% (P?=?0.0004), so did the panicle numbers per area (P?=?0.036). The yield increase in SRI was associated with the increased number of panicles, which should have resulted from enhanced tiller development under shallow water level during the vegetative stage. The increased number of panicles was, however, counteracted by the reduced number of spikelets per panicle and resulted in nonsignificant increase in the spikelet density, defined as number of spikelets per unit area of crop. This dampening change in spikelet number per panicle could have been caused by limited supply of either nitrogen or carbohydrate during the panicle development stage under the intermittent water supply. A greater yield increase by SRI could be expected by improving nutrient or water management during the reproductive stage.  相似文献   

5.
Rainfall amount drawn by typhoon events accounts for a significant portion of annual rainfall in Taiwan. Changes in typhoon rainfall due to climate change may have severe consequences for water resources management. A stochastic simulation approach is proposed for evaluation of changes in typhoon rainfall under certain climate change scenarios. The number of typhoon events and total rainfall of individual typhoon events are, respectively, considered as random variables of the Poisson and Gamma distributions. Climate change scenarios were set by varying various degrees of changes in average number of typhoon events annually and the mean of event-total rainfall. Using stochastic simulation, basin-wide annual typhoon rainfalls were simulated for the Shihmen Reservoir watershed in northern Taiwan. It is found that 10% increases in average annual number of typhoon events and mean event-total rainfall will result in 18% increase in the annual typhoon rainfall of 5-year return period, whereas the annual typhoon rainfall of 10-year return period will increase by 15% under the same climate change scenario. Such increases may cause significant increase in reservoir sediment and pose challenges to reservoir management.  相似文献   

6.
Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.  相似文献   

7.
ABSTRACT

Information on comprehensive evaluation of agricultural innovations is often limited. This study provides an overview of multidisciplinary evaluation of a lowland rice variety, WITA 9 (released in Côte d’Ivoire in 1998), with respect to its agronomic performance, grain quality, resistance to diseases, adoption by farmers, impact on productivity and farmers’ income, and marketability. WITA 9 had the highest paddy yield among the tested varieties including an international check (IR 64) and recently developed varieties adapted to this country. WITA 9 had a higher amylose content (26–28%) than others tested. This study confirmed its resistance to bacterial leaf blight, Rice yellow mottle virus (RYMV), and rice blast. A household survey showed that the adoption rate was 24%, its paddy yield advantage was 0.7 t ha–1, and its adoption increased farmer’s income by US$ 91 ha–1 per season. A market study showed that consumers’ willingness to pay was higher for WITA 9 than any other locally produced rice variety and comparable to imported rice in one of two markets. We conclude that WITA 9 is an ideal innovation for enhancing productivity and rice import substitution in Côte d’Ivoire. An effective seed delivery system and enhancing farmers’ and consumers’ awareness of this variety are vital for accelerating impact.  相似文献   

8.
Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.  相似文献   

9.
Hyderabad is one of the fastest growing cities in India. To meet its rapidly expanding water needs, it constructed and began withdrawals from the Singur reservoir, located on a tributary of the Godavari River, in 1991. Administrative rules define allocation of water from the reservoir but prioritize Hyderabad urban needs over much longer established agricultural uses. Furthermore, the agricultural sector receives less water than even these rules allow, and urban withdrawals have changed the quantity and the timing of the water, which is available to agriculture. An increase in groundwater use by farmers may have been one response to these changes, with possible implications for surface and groundwater users further downstream. While proposals have been put forth to compensate the agricultural sector in general and the farmers directly affected by reallocation, for example by improving access to wastewater for irrigation downstream from Hyderabad or by conveying wastewater for irrigation purposes downstream Singur reservoir, compensation has not been implemented to date. The Hyderabad case study clearly highlights the advantages for devising and implementing arrangements to regulate the transfer of water from agriculture to cities, allowing a move from sectoral competition for water to efficient management of a scarce resource.
Mattia CelioEmail:
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10.
A good water users’ organization (WUO) is a significant factor in the practical success of an irrigation project. The major duties of WUOs are to operate and maintain their irrigation facilities and to perform the financial and organizational management. This paper analyzes the history and present situation of three WUOs in the Chao Phraya Delta, Thailand which have been awarded for their successful activities: namely, two pilot integrated water user groups (IWUGs) and one pilot water users’ association. The results of a field survey and questionnaire revealed the users’ past experience, methods of irrigation management, and social mobilization efforts. The main results of our analysis are as follows: (1) among the three WUOs, only the IWUG Sao Hi Unity Agriculture Irrigation (IWUG SHUAI) can be regarded as a successful case in terms of long-term management, (2) as a pumping irrigation project, the IWUG SHUAI entails an upfront electricity cost, which gives farmers added impetus to organize a management system and budget, and to learn from past failures, and (3) in contrast, the member farmers in the gravity irrigation projects lack the impetus to realize the necessity of a common management budget, a situation which can be improved only by the education of the leaders and clear explanation to the member farmers.  相似文献   

11.
Paddy and Water Environment - This study examines farmers’ preferences for weather index insurance (WII) in the Ayeyarwady Delta, Myanmar, using discrete choice experiments. It employs data...  相似文献   

12.
During the production of tuwo from laboratory-contaminated corn (AFB1:150 mcg/kg) and sorghum (AFB1:87.5 mcg/kg) grains, reductions in the aflatoxin-B1 levels of pastes boiled for 30 min and 60 min were found to be 68.0% and 80.8%, respectively. In the preparation of ogi from contaminated corn and sorghum grains, reductions of about 72.5% and 71.4%, respectively, were obtained after fermentation at ambient conditions. Reconstitution of ogi paste into a porridge (akamu) considerably reduced the AFB level.  相似文献   

13.
Wheat flour is generally supplemented with α-amylases to increase maltose levels in bread dough and increase loaf volume. While the preference of yeast for glucose and fructose over maltose as substrate for fermentation is well documented, the impact of maltose versus glucose producing enzymes on bread dough fermentation kinetics and bread sugar levels is ill documented. Hence the impact of α-amylase, α-glucosidase and glucoamylase action on both aspects was investigated. Glucoamylase and α-amylase increase the total fermentable sugar content of dough, while α-glucosidase only affects the glucose/maltose ratio. Due to their effect on total fermentable sugar levels, addition of α-amylase or glucoamylase prolongs the total productive fermentation time, while this is not the case for α-glucosidase. In contrast to α-amylase, both glucoamylase and α-glucosidase supplementation leads to higher CO2 production rates during the initial stages of fermentation. In the final bread product, different sugar levels are observed depending on the dosage and type of starch-degrading enzyme. The results of this study imply that long and short fermentation processes benefit from α-amylase and α-glucosidase addition, respectively, while glucoamylase supplementation is suitable for both long and short fermentation times.  相似文献   

14.
Studies on the enhancement of the traditional production of Ugba (a protein-rich fermented food) from African oil bean seeds were undertaken by fermenting the bean seeds at different temperatures, relative humidities (RH) and microenvironments. Fermentation was monitored by pH, texture, amino-nitrogen content and the viable cell count of the substrate. The 40 °C, 98% RH or the 130 m high density polyethylene (HDPE) treatment increased the fermentation microflora from ca. 106 CFU/g to ca. 108 CFU/g with high initial changes in pH (5.8–ca. 7.9) and texture (2.0 kg/cm2 to between 1.4 kg/cm2 and 0.9 kg/cm2) in 24 hours. Products with amino-nitrogen contents of between 12.00 mg N/100 g dry matter and 14.00 mg N/100 g dry matter were obtained in 3 days. The cell count of the 30 °C, 80% RH or 70 m treatment increased from 106 CFU/g to ca. 107 CFU/g and the pH increased from 5.8 to about 6.7 with a coincident decrease in the texture value from 2.0 kg/cm2 to about 1.7 kg/cm2 in 24 hours. Products with amino-nitrogen contents between 15.00 mg N/100 g dry matter and 19.2 mg N/100 g dry matter were obtained after 3 days. Changes in the fermentation indicators were not significant at p0.05 (pH and texture) and at p0.01 (amino-nitrogen) after 3 days for the 25 °C, 59.9% RH or 50 m low density polyethylene (LDPE) treatment. Products of fermentation at the combined optimal conditions (80% RH, 35 °C and 70 m HDPE) compared very well with the traditionally fermented products in terms of pH, texture and amino-nitrogen content.  相似文献   

15.
Randolph Barker 《Rice》2011,4(3-4):184-186
Often overlooked is the importance of early-maturing rice varieties with their ability to escape droughts, avoid floods, and in some localities, open up the opportunity for double cropping. Most varieties grown in the tropics until the last half century matured in 150 to 180 days or longer and were photoperiod sensitive. However, non-photoperiod sensitive one-hundred-day varieties were grown in the Champa Kingdom in what is now Central Vietnam centuries ago. How these varieties moved into Song Dynasty China and the impact of the early-ripening rice on population growth in South China is well documented. However, the origin of the Champa varieties is less clear. According to a recent DNA test (see below), the Champa varieties belong to the aus sub-population. The aus have the characteristics of both indica and japonica and originated in the hill areas of what are now Eastern India, Bangladesh, and Myanmar. Because the Champa Kingdom adopted the Indian language and religion, at least in the higher courts, it seems logical that the Champa rice must have been disseminated from the hilly areas in the Indian sub-continent to Central Vietnam and eventually to China—first Fujian and later to the Yangtze region during the Song Dynasty in the eleventh century.  相似文献   

16.
Eight streptophenazines (A–H) have been identified so far as products of Streptomyces strain HB202, which was isolated from the sponge Halichondria panicea from the Baltic Sea. The variation of bioactivities based on small structural changes initiated further studies on new derivatives. Three new streptophenazines (I–K) were identified after fermentation in the present study. In addition, revised molecular structures of streptophenazines C, D, F and H are proposed. Streptophenazines G and K exhibited moderate antibacterial activity against the facultative pathogenic bacterium Staphylococcus epidermidis and against Bacillus subtilis. All tested compounds (streptophenazines G, I–K) also showed moderate activities against PDE 4B.  相似文献   

17.
There is an urgent need for the international community to address not only the issues of preserving the global environment and reducing poverty in developing countries, but to also face up to new challenges, such as providing assistance to the reconstruction in Afghanistan. Furthermore, it is necessary to address these issues and challenges by means of mutual collaboration. This latter point has been the subject of lively discussion.In this paper, we describe a new direction in international cooperation taken by the Rural Development Bureau of the Ministry of Agriculture, Forestry and Fisheries, Japan in response to the trend of international discussions. This shoulb be achieved by utilizing Japans experience and expertise gained in the development of its own paddy rice agriculture.Specifically, based on the philosophy that sustainable agricultural and rural development can conserve a regional environment, the Bureau intends to undertake: (1) extension of the results from a cooperation project to other regions, by modifying it and converting it to multi-purpose use; (2) collaboration with aid-related entities in Japan and abroad, and dissemination of related information to them; and (3) promotion of cooperation focused on a specific topic.Furthermore, the Bureau will promote the following matters as the basis for international cooperation in each major task. (1) Contribution towards sustainable water use. (2) Extension of the participatory integrated rural development, and its modification for reconstruction assistance. (3) Extension of desertification control, and its modification and conversion for multi-purpose use. (4) Conversion of the technology for soil erosion control into multi-purpose use.  相似文献   

18.
Two varieties of ‘Vicia faba L.’equina andminor, were studied. Theequina variety had a higher polyphenolic content than theminor variety. Both varieties significantly inhibited rat growth rate and ‘in vivo’ intestinal glucose transport, theequina variety being a more powerful inhibitor than theminor variety. However the raw legume fed animals showed a normal urinary excretion rate of 3-Methylhistidine.  相似文献   

19.
20.
Candidatus Liberibacter solanacearum’ (Lso) is the putative causal agent of zebra chip disease (ZC). Late season Lso-infected potatoes that are known to be asymptomatic at harvest may continue to develop symptoms by the time of shipment to consumers. This study observed symptom development, Lso titer changes, and changes in symptom-associated phenolic compounds in Lso-infected yet asymptomatic tubers placed at different holding temperatures. ZC symptoms present in freshly-sliced tubers were more severe in ‘Red La Soda’ or ‘Russet Norkotah’ tubers held at 3 °C than at 6 °C or 9 °C. However, Lso titers showed considerable variability in both cultivars over time and at these holding temperatures. Phenolic compound levels, known to be associated with ZC symptom severity, in tubers kept at 3 °C were greater than those kept at 6 °C or 9 °C and increased over time. These results demonstrate that ZC could develop in tubers kept in cold storage, with those kept at 3 °C having more ZC development than those kept at 6 °C or 9 °C.  相似文献   

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