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1.
The multi-functionality of paddy farming in Korea 总被引:3,自引:3,他引:0
The multi-functionality of paddy field and irrigation water has become a hot issue recently in Asian monsoon regions. Asian people know why they have to conserve the paddy farm where the sustainable functions have been historically inherited and maintain the rural community where the unique cultures have been traditionally created. But, the real value of multi-functionality has not been clearly highlighted as much worthy as it has. We should evaluate the characteristics of multi-functionality of paddy farming correctly and transmit them to the people of Western countries under quite different conditions of upland fields. In Korea, several studies on the multi-functionality of paddy farming have been performed with positive and negative viewpoints. This paper shows the results and the discussion of the researches to get global recognition on the multi-functionality of paddy farming.
相似文献
Tai-Cheol KimEmail: |
2.
In Northeast Thailand, which overlaps with an erosional plain that is not suitable for irrigation because of poor water resources and terrains that prevent efficient water distribution, farmers have long supplied water to surrounding paddy fields by blocking rivers completely with earthen bunds. Although such a traditional irrigation system fits well with the characteristics of Northeast Thailand, those who are concerned with modern irrigation development projects in Northeast Thailand seem to have been paying little attention to it. The present study was performed to facilitate development of more appropriate irrigation systems in Northeast Thailand by providing information regarding traditional irrigation methods. We investigated the traditional irrigation methods with earthen bunds at three study sites, and our results indicated that styles of irrigation vary with riverbed slope. The traditional irrigation system that is used in most of Northeast Thailand is different from ordinal weir irrigation, in that paddy fields are not irrigated by gravity flow but by backwater of earthen bunds. Our results suggest that the development of more successful irrigation systems would be possible through improvement of the design ideas of traditional irrigation methods.
相似文献
Keisuke HoshikawaEmail: |
3.
Improving irrigation performance is a crucial issue for agriculture and irrigation development in the Lower Mekong River Basin
to secure food production for people’s livelihoods. Irrigation efficiency is the most important indicator to determine the
performance of an irrigation scheme. This study looks at water management practices and irrigation efficiency in three pilot
sites in the Lower Mekong River Basin: the Numhoum scheme in Laos, the Huay Luang scheme in Thailand, and the Komping Pouy
scheme in Cambodia. Irrigation efficiency and water productivity were analyzed using a water balance approach at the irrigation
scheme level and results in the pilot areas show efficiencies that are definitely higher using this approach than by using
the classical concept. Lower water productivity was observed at pilot schemes in areas of single cropping and higher productivity
in areas where multiple agricultural activities were practiced. Strict and active water management is required to control
and save water to meet agricultural demand and have sufficient water to expand cultivation areas while avoiding shortages.
Promoting multiple uses of water for various agricultural activities in command area will increase water productivity.
相似文献
Hiroshi OkudairaEmail: |
4.
Gilbert Levine Chih-Hung Tan Yutaka Matsuno C.-C. Huang Randolph Barker 《Paddy and Water Environment》2006,4(4):245-250
This paper presents protocols for estimating the magnitudes and monetary values of two non-market outputs from paddy rice production. The protocols were developed during a workshop held in Taiwan in 2004 to set guidelines or protocols for measuring the multi-functional attributes of positive and negative externalities of paddy rice. The externalities attributed to paddy rice include groundwater recharge, subsidence reduction, flood damage amelioration, change in water quality, change in air quality, and preservation of scenic value. Methodologies were set forth for measuring and valuing each of these externalities. Two that reflect differences in complexity – groundwater recharge and change in air quality – are discussed here. The protocols consider regional variation, the need for evaluation of net effects, and the avoidance of double counting. The conclusions presented are those from the workshop as a whole.
相似文献
Randolph BarkerEmail: |
5.
A paddy-field consolidation (PC) project was carried out with large subsidies as a public investment by prefectural governments
in order to improve agricultural productivity in Japan. The purpose of this study is to analyze the quantitative benefits
and costs of the PC projects. A benefit incidence (BI) analysis was used in view of the far-reaching effects on farmers to
consumers. The results were as follows. First, with the recent decline in rice price, certain farmer benefits primarily derived
from the projects have been transferred to consumers through rice price. The transfer ratio was more than half of the total
improvement effect of rice productivity which occurred on the farmers’ side, and all economic sectors including farmers and
consumers received net benefit even though all sectors paid construction costs or taxes. Therefore, maintaining flexibility
in rice price plays an important role to secure net benefits and obtain an agreement of all people involved in the project.
Second, some benefits with regard to effects on the rural environment that was not expected at the time of planning were revealed
on many project sites. Evaluating these intangible effects will be more important for the tax payers in order to evaluate
how the environment friendly planning of the project achieved benefits.
相似文献
Yoji KunimitsuEmail: |
6.
Water transfer from agriculture to urban domestic users: a case study of the Tone River Basin, Japan 总被引:3,自引:1,他引:2
Agricultural water reorganization measures (AWRM) is an approach that has been adopted in Japan for more than 30 years to
capture excess water from agriculture for other uses by relying on the modernization of existing irrigation infrastructures.
This paper reviews the history and processes of four such permanent water transfers by AWRM in the Tone River Basin, specifically
those conducted in the Saitama Prefecture, Japan. The benefit of AWRM for the agricultural sector is the lowering of rehabilitation
costs by sharing part of it with the city sector. AWRM does not require saving water at the on-farm level. Instead, the labor
requirement of farmers is reduced by the rehabilitation and installation of pipelines. The benefit to the city is the lower
cost, when compared with costs for the development of new water resources, and the relatively short duration of the project,
which are important factors in an environment of the rapid increase in domestic water demand.
相似文献
Yutaka MatsunoEmail: |
7.
This paper aims to evaluate the social value of the environmental multifunctionality of paddy fields in Taiwan; through individual
consumers’ direct expressions of their perceived benefit and to provide the empirical data thus collected for the reference
of the decision makers in the government. This study use contingent valuation method (CVM) to evaluates the value of environmental
multifunctionality of paddy fields from the purposefully selected pool of samples in Taiwan. The result shows if judged by
the threat that free trade poses to the retention of arable land, most respondents give a value of 114 NT/household/month
to 115 NT/household/month for 1% reduction of arable land to be restored to the existing level; and168 NT/household/month
to 181 NT/household/month for a reduction rate of 4%. There are 7,394,758 households in Taiwan. The aggregating result is
10,116,028,944 NT/year to 10,204,766,040 NT/year for 1% reduction of arable land to be restored to the existing level; and
14,907,832,128 NT/year to 16,061,414,376 NT/year for a reduction rate of 4%.
相似文献
Ya-Wen ChiuehEmail: Email: |
8.
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.
相似文献
Mattia CelioEmail: |
9.
Through empirical simulations of the Taiwanese rice market, we estimate the effects of agricultural policies designed to ensure optimal levels of two multifunctional outputs, groundwater recharge, and methane emissions. Optimal policy instruments differ by region to reflect land quality and the conditions of the aquifers in major rice production regions. The effects on rice production, resource allocation, and returns to farm assets differ as well.
相似文献
Richard N. BoisvertEmail: |
10.
Agriculture's multifunctional role as provider of non-commodity outputs has received increased attention in the debate on the future of agricultural policy. To identify appropriate economic policies, a distinction must be made between concerns involving market failure and a consequent misallocation of resources, and those relating to distributional issues. We argue that it is essential to restrict the concept of multifunctionality to non-commodity outputs involving technical externalities or public goods and for which market failure and the misallocation of resources are important (e.g., amenity values and agricultural pollution). Other non-trade concerns, such as rural incomes and employment and food security, involve distributional issues, but no resource misallocation. This distinction makes it possible to identify different types of domestic policy measures to address them effectively and efficiently. Through reference to an empirical application to Taiwanese paddy rice policy, we illustrate that the most effective way to reconcile non-trade concerns is through policy measures that correct for market failure by valuing non-commodity outputs appropriately and a separate set of measures that address distributional issues.
相似文献
David BlandfordEmail: |
11.
G. Levine 《Paddy and Water Environment》2007,5(4):279-284
The Lower Rio Grande Valley is a sub-tropical area with a productive irrigated agriculture, but with an over-committed single
water resource. It is experiencing a rapidly growing population that is placing increasing pressure on the water resource.
This, combined with expanding urban areas and land moving out of agriculture, has resulted in a vigorous water market, with
transfers from agriculture to municipal uses. For the US portion of the valley, transfers from agriculture to municipalities
are either short-term (usually 1 year) or permanent. Prices vary depending upon the location and timing, and result from negotiations
between the parties. Over time, and not without difficulty, the water market has been facilitated by appropriate enabling
legislation, water rights that have been validated judicially, and an efficient transfer mechanism that has a minimum of transaction
cost. Government involvement is primarily for protection of the public, and to facilitate the transfer process.
相似文献
G. LevineEmail: |
12.
Farmers in some parts of the Indochina Peninsula have been using earthen weirs to supply water to their rice fields, and the
use of such weirs is especially prevalent in Northeast Thailand. Although now a typical rain-fed rice cultivation area, a
significant percentage of rice fields in Northeast Thailand used earthen weirs before the extensive expansion of rain-fed
rice fields that occurred in the early 20th century. In this study, we clarified some of the historical changes associated
with the construction and use of earthen weirs and their effects on rice production. In particular, we investigated some of
the topographic effects, such as terrain, catchment size, and slope grade, on water delivery. In addition, water delivery
methods, construction periods, and the discontinued use of earthen weirs were examined with respect to regional influences
and topography. Earthen weirs were found to be most suitable in areas that exhibited complementarity between the riverbed
slope and the water catchment. The type of earthen weir was dependent on the magnitude of the riverbed slope. Earthen weirs
have been constructed continuously on steeper upstream slopes of rivers for more than a century, while weir construction on
lower riverbeds with larger catchments appears to be more recent.
相似文献
Keisuke HoshikawaEmail: |
13.
Kazumi Yamaoka Tatsumi Tomosho Masaru Mizoguchi Mikiko Sugiura 《Paddy and Water Environment》2008,6(1):115-128
In Japan, a developed country in Asia, the Land Improvement Act systems have worked as a measure of social capital accumulation
as well as an adjective law in implementing irrigation projects since 1949. This paper illustrates the status and problems
in applying the concept of social capital to agricultural and rural development policy systems in developing countries, EU
and Japan. The results obtained are summarized as follows: (1) it is desirable that governments formulate public policies
that are appropriate for correcting inefficiencies in resource distribution for accumulating social capital, so that the governments
play a significant role in developing and supporting social capital; (2) the effect of policies in the areas, where government-supported
land improvement projects have been implemented, has been improved, subsequent to which the efficient use of the national
budget allocated for the projects has been improved, while the projects significantly contribute to the national land conservation
and social stability by continuously promoting minimum social capital accumulation nationwide. In addition, Japan and countries
in the Asian monsoon region, which hold the five elements in common that constitute the characteristics of rice field irrigation
in humid climates, should take over the advantages of the land improvement project system while learning from the success
achieved by the LEADER+ programme in Europe, where society precedes Asian countries concerning the problems of decline in
the birth rate, and expansion of an aging society.
相似文献
Kazumi YamaokaEmail: |
14.
H. Jochemsen 《Potato Research》2008,51(1):59-73
Because of objections and worries related to genetically modified organisms (GMOs), the approval of GMO crops is a long and
expensive process. Recently some researchers argued that a specific form of genetic modification, cisgenesis, would be safer
and ethically more acceptable and therefore require a less stringent assessment. In this paper cisgenesis, as defined in recent
literature, is ethically evaluated. After some general remarks on ethics in science and technology, two different basic attitudes
towards reality are sketched as an evaluative framework for interventions in nature. Combined with general characteristics
of biotechnology in agriculture and a view of the role of genetic information in organisms, that framework helps to formulate
an ethical distinction between and evaluation of cisgenesis and transgenesis. It is argued that there is a significant ethical
difference between transgenesis and cisgenesis, but that nevertheless any form of genetic modification should be integrated
in a broader normative understanding of agriculture in order to work towards a more sustainable agriculture.
相似文献
H. JochemsenEmail: |
15.
E. Audsley 《Grass and Forage Science》1974,29(4):291-298
A linear programming model of a high-temperature grass-drying enterprise is described. From information about seasonal crop response, area of crop available and management constraints, the model determines the harvesting schedules which give greatest returns, less costs, from the enterprise over the season. This information can be used to examine the effects of long-term strategic decisions or to evaluate economically data on new crops from field experiments. For example, assuming a fixed cost of λ70,000/year for a high-temperature grass-drying installation and what is considered to be reliable input data for 1972, the returns less costs for optimum harvest schedules from different areas or crop varieties are:
The model can also provide information con cerning tbe limitations imposed by equipment stage of tbe process and management re straints sucb as limitations on overtime and shut downs for holidays or maintenance. 相似文献
Corp area | Surplus | |||
---|---|---|---|---|
Grass ac (ha) | Lucerne ac (ha) | Return, £ | Less costs £/ac(£/ha) | crop ac (ha) |
800(324) | 0(0) | 42,849 | 536(132.3) | 0(0) |
1000(405) | 0(0) | 60,286 | 603(1489) | 205(83) |
600(243) | 200(81) | 46,731 | 58.4(1442) | 0(0) |
800(324) | 200(81) | 65.661 | 65.7(1621) | 109(44) |
16.
Water management is an important factor in regulating soil respiration and the net ecosystem exchange of CO2 (NEE) between croplands and atmosphere. However, how water management affects soil respiration and the NEE of paddy fields remains unexplored. Thus, a 2-year field experiment was carried out to study the effects of controlled irrigation (CI) during the rice season on the variation of soil respiration and NEE, with flooding irrigation (FI) as the control. A decrease of irrigation water input by 46.39% did not significantly affect rice yield but significantly increased irrigation water use efficiency by 0.99 kg m?3. The soil respiration rate of CI paddy fields was larger than that of FI paddy fields except during the ripening stage. Natural drying management during the ripening stage resulted in a significant increase of the soil respiration rate of the FI paddy fields. Variations of NEE with different water managements were opposite to soil respiration rates during the whole rice growth stages. Total CO2 emission of CI paddy fields through soil respiration (total R soil) increased by 11.66% compared with FI paddy fields. The increase of total R soil resulted in the significant decrease of total net CO2 absorption of CI paddy fields by 11.57% compared with FI paddy fields (p < 0.05). There were inter-annual differences of soil respiration and the NEE of paddy fields. Frequent alternate wetting and drying processes in the CI paddy fields were the main factors influencing soil respiration and NEE. CI management slightly enhanced the rice dry matter amount but accelerated the consumption and decomposition of soil organic carbon and significantly increased soil respiration, which led to the decrease of net CO2 absorption. CI management and organic carbon input technologies should be combined in applications to achieve sustainable use of water and soil resources in paddy fields. 相似文献
17.
La purification d'un extrait mycélien soluble d'une souche deR. solani AG3 par chromatographie d'exclusion permet de recueillir une fraction antigénique. Une lapine est immunisée par voie intradermique.
L'immunsérum titre 0,125 par la technique de double-diffusion en agarose. Différentes techniques sérologiques (immunodiffusion,
électrotransfert suivi de révélation des fractions antigéniques, coloration immunoenzymatique du mycélium) sont appliquées
à des souches deR. solani AG1, AG2, AG3, AG4, AG5, AG6, AG7, AGBI et deCeratobasidium CAG1, CAG2, CAG3, CAG4 et CAG5. Le sérum se révèle spécifique des souches AG3.
A soluble mycelial extract ofR. solani AG3 was purified by size exclusion chromatography. Five peaks were present in the elution profile: the first was well defined
and of large volume. It was retained to immunise a female rabbit by intradermic injection. The titre of the antiserum determined
by double immuno-diffusion in agarose was 0.125. The antiserum was tested on isolates ofR. solani AG1, AG2, AG3, AG4, AG5, AG6, AG7, AGB1 and ofCeratobasidium CAG1, CAG2, CAG3, CAG4 and CAG5 (Table 1) using three different methods:
相似文献
– | - immunodiffusion with the test material adjusted to 3 mg/ml of proteins. Only AG3 isolates formed a single precipitation line (Fig. 1). |
– | - electrotransfer and immuno-blotting. Test samples containing 8 mg/ml of proteins were electrophoresed under natural conditions in a discontinuous system. The proteins were then electrotransferred to a nitrocellulose membrane. Immunoenzymatic staining showed that only one band was present in AG3 isolates (Fig. 2). |
– | - immunoenzymatic labelling of the mycelium demonstrated the presence of dark granules on the cell wall of only AG3 isolates (Fig. 3). |
18.
Delivery management water requirement (DMWR) is the use of bypass water in paddy field irrigation to help maintain desired water levels in irrigation canals and to distribute water to paddy plots in a uniform manner. Diverted irrigation water (DIW), DMWR, and the DMWR/DIW ratio were investigated for concrete lined irrigation ditches with large-sized paddy plots (100 m×100 m) during irrigation periods (May to mid-September). DIW and DMWR were measured at 5- to 10-day intervals at the inlets and outlets of irrigation ditches on stable water supply days. The mean DMWR/DIW ratios in irrigation ditches L1 and L2 over 3 years were 36 and 34%, respectively. The mean DMWR/DIW ratios displayed month-to-month and year-to-year variation. The monthly mean DMWR/DIW ratios were highest (55 and 71%) in June and lowest (<20%) in August and September. The annual mean DMWR/DIW ratios during a dry year markedly decreased to 11%, compared with 42% in other years. The decrease was due to the small DIW and farmers water management to maximize capture of limited irrigation water during the drought. The DMWRs in May and June were significantly (p<0.01) correlated with the DIWs, indicating that high DMWR in May and June are attributed to excessive DIW. 相似文献
19.
Trois méthodes de test de résistance sont comparées — méthodes en pot, en conteneur fermé et en bo?te de Petri — pour 5 génotypes
de pommes de terre à résistance partielle vis-à-vis deGlobodera pallida Pa3 à l'égard de 2 populations de Pa3 à virulence différente.
Les conclusions sont les suivantes:
相似文献
1) | les populations et l'interaction génotype × population ont des effects significatifs sur l'éclosion des kystes parentaux et le développement des nouveaux kystes ou des femelles (Tabl. 1). |
2) | la transformation utilisée sur les données ou l'absence de transformation agit sur les regroupements de même signification entre génotypes (Tabl. 2 et 4). |
3) | le pourcentage de résistance de chaque génotype dépend du témoin, de la population et du test utilisés (Tabl. 6): la méthode en conteneur fermé est la moins sévère, la méthode en bo?te de Petri est la plus sévère. |
4) | selon le niveau de résistance exigé par la réglementation, on choisira telle méthode et telle population. |
20.
In the Hetao Irrigation Districts of the Ningxia autonomous region, Upper Yellow River Basin, the continuous deep flooding irrigation method is used for the rice paddies. The field irrigation water use during the rice-growing season is two to three times higher than in other regions of North China where water-saving practices have been introduced. This paper, based on the data measured in experimental rice fields and sub-branch canal systems, presents main results concerning crop evapotranspiration, percolation and irrigation requirements for deep and shallow water irrigation. Causes for water waste relate to both the lack of regulation in supply and distribution canals and to the poor management of paddy fields. The potential for water saving is discussed using water balance data. Improved irrigation techniques and water management strategies, including the shallow water irrigation method, are suggested considering the expected impacts and benefits. Replacing the current continuous deep flooding with the shallow-ponded water irrigation method may reduce the growing season irrigation water use from 1,405 to 820 mm in average, with a likely increase in yields of 450 kg/ha. Water productivity would then increase from 0.49 to 1.03 kg/m3. Adopting improved canal management and modernization of regulation and control structures may lead to decreasing the gross irrigation demand from the present 3,100 mm to about 1,280 mm, which would highly benefit the environmental conditions in the area. 相似文献