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1.
Finbarr G. Horgan Enoka P. Kudavidanage Anura Weragodaarachchi Daniel Ramp 《Paddy and Water Environment》2018,16(2):225-241
The Nilwala Ganga Basin of Sri Lanka includes important natural wetlands that are habitat for vulnerable animal and plant species. Flood protection and intensive rice production in the Basin have resulted in degraded acid soils and declining rice yields. However, traditional ‘maavee’ rice production outside the flood protection scheme has continued to generate a high-value rice product. This study reports on interviews conducted with farmers and other stakeholders to document the production practices and the potential environmental and economic benefits associated with maavee rice paddies. The maavee production system has prevailed for at least several decades. Farmers apply no chemicals to their paddies, relying instead on alluvial deposits as a source of nutrients, and on the natural pest and disease resistance of their traditional varieties. The maavee rice product can attain three times the selling price of rice from conventional farms making it more economically viable than conventional rice production. However, much of maavee production is for home consumption and the system is threatened by increasing labour costs, an ageing farming population and pressures to increase rice yields. Non-invasive production practices and the proximity of maavee paddies to regenerating wetlands in the Kirala Kele Sanctuary suggest that traditional paddies may constitute an important habitat for vulnerable wildlife; however, maavee farmers also perceive wetland birds as potentially damaging to rice. Based on a SWOT (strengths, weaknesses, opportunities and threats) analysis, we make recommendations for future research needs and potential management actions to safeguard the environmental and economic sustainability of the maavee system. 相似文献
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Sirirat Kiatpathomchai P. Michael Schmitz T. S. Amjath Babu Sutonya Thongrak 《Paddy and Water Environment》2008,6(3):319-326
Rice and shrimp farming are two important economic activities in rural southern Thailand that compete each other in land allocation
leading to land use conflicts. Moreover, it can be observed that the conversion of rice fields to shrimp farms is already
extended from coastal areas to the inlands. These conversions are making more area be saline which is essential condition
for shrimp cultivation but deleterious for rice farming. We are looking at the unidirectional externalities originating from
the conversion which brings the productivity of adjacent rice fields further down. This study attempts to quantify the external
effects on rice yield and efficiency of rice farming by constructing three models. Model I, we assess the rice yield function
by using the multiple linear regression while in Model II, we attempt to delineate the technical efficient frontier of rice
farms by using an input oriented non-parametric approach, so called data envelopment analysis. Model III, we probe into the
factors influencing technical efficiency scores using the Tobit regression. Database of the study is constituted by primary
survey data from 120 rice farms in Songkhla province for the crop year 2004/2005. The 30 out of 120 sample farms have been
affected by externality of shrimp farming. The empirical results of all three models show that shrimp farming externalities
caused a production drop of 467–515 kg paddy rice per ha and significantly affect the technical efficiency of rice farms.
The measures of internalizing this externality are discussed. 相似文献
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Hiroshi Ikeura Sengthong Phongchanmixay Salermphon Phonsangone Phetyasone Xaypanya Somphone Inkhamseng Somnuck Soubat 《Paddy and Water Environment》2016,14(2):343-353
The unevenness of rice productivity in lowland areas is caused by differences in farming techniques, accessibility of water, planting environment, and other field-specific factors. In order to increase rice production in low-productivity fields, this study examined the factors affecting yield reduction. In this study, the influence of water conditions, farming activities, and soil fertility on rice yield were analyzed in a lowland area located in the northern part of Lao PDR. A field survey was conducted in a village in Vientiane Province during the rainy season of 2013. Water conditions were observed (i) prior to land preparation, (ii) between land preparation and transplanting, and (iii) after transplanting. Farming activities were recorded in each lowland rice field weekly from June to August. Yield surveys were also conducted in 47 field blocks, and soil samples were collected for soil fertility analyses. The ponding of fields commenced in the middle of June, and extended from the upper part to the lower part of the lowland area. Transplanting was conducted following the distribution of surface water, and no serious water shortages were observed after transplanting in the surveyed areas. There was no correlation between grain yield and the content of total nitrogen or available phosphorus in the field soil. Significant differences in grain yield were detected between direct and plot-to-plot irrigation, early and late ponding, and transplanting in July and in August. The results suggest that water shortages and the delay of field ponding before land preparation led to late transplanting which caused yield reduction. 相似文献
4.
Converting rice paddy to dry land farming in the Tai Lake Basin,China: toward an understanding of environmental and economic impacts 总被引：1，自引：0，他引：1
Water pollution is a well-known major problem in the Tai Lake Basin, China. Compared to industries and domestic sewage, non-point pollution from agriculture is more difficult to detect, measure, and control. Therefore, a range of policies has been formulated, among which is that of ‘adjustment of the planting structure.’ However, this policy during implementation has been used to simply convert paddy fields to dry land and food crops to cash crops. More surprisingly, to date, no research has provided evidence that such an agricultural land-use change contributes to the reduction of agricultural nutrient pollution. Based on an extensive farm survey, this research finds that conversion of rice paddy to dry land farming has not generated a positive effect on nutrient pollution control. It is estimated that nitrogen runoff from agricultural land has increased by 11 %, while phosphorus runoff has increased more than two times since land-use patterns changed, as farmers are inclined to apply more fertilizer on dry land than in paddy fields. However, this agricultural land-use change is economically effective as land-use conversion increases the net profits of farming in a significant way. It is demonstrated that, compared to environmental concerns, economic considerations are seen to have greater benefits after such an adjustment in the planting structure. These findings have important implications for policy making by local authorities in their efforts to improve environmental management and pollution control in their territories. 相似文献
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Rodents are a severe and chronic pest for farmers in the upland farming system of Lao PDR where upland rice is the predominant subsistence crop. Farmers participated in developing and implementing a series of ecologically-based rodent management (EBRM) strategies designed to reduce the impact of rodents in their upland farming system. These were tested in replicated Treatment and Reference sites in two provinces of northern Laos. A survey was conducted with farmers to determine their knowledge, attitudes and practices prior to and after the implementation of EBRM. This paper reports on the results of the post-implementation survey and compares results with the pre-implementation survey. The survey revealed that rodents remained the most important pest for these farmers. The mean estimated yield loss of upland rice was 12%. There was a significant reduction in the yield loss from pre- to post-treatment, but the time by treatment interaction was not significant. Trapping rodents in the fields remained the most important control strategy for these farmers and also was considered the most effective method. There was an increase in effort expended by farmers in controlling rodents post-treatment on Treatment sites in Luang Namtha, but no difference for other sites. The money spent on controlling rodents was lower on all sites post-treatment except for Treatment sites in Luang Namtha. Farmers on the Treatment sites in Luang Namtha had the lowest effort during the pre-treatment period and thought they needed to increase their rodent management efforts because of their involvement in this project. As a result of the project, farmers were more aware of the problems of rodents and were interested in adopting EBRM strategies. 相似文献
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提高水稻家庭农场全要素生产率是贯彻落实“谷物基本自给、口粮绝对安全”新粮食安全观的重要举措。本文基于长江流域612户水稻家庭农场的微观调查数据,运用三阶段DEA模型实证研究水稻家庭农场全要素生产率。研究表明,年龄、受教育程度、农地细碎化程度等环境因素对水稻家庭农场全要素生产率具有重要影响;水稻家庭农场的耕种面积和规模报酬呈现倒U型关系,且适度经营规模区间为8.0～9.3 hm2;水稻家庭农场全要素生产率未达到有效的主要原因是规模效率相对较低。基于此,本研究主要从规范农地流转市场、完善家庭农场市场竞争机制、加快建设高标准农田、提升家庭农场主自身能力建设等方面提出相关对策建议,以有效提升水稻家庭农场全要素生产率。 相似文献
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稻作方式对优质食味品种南粳9108的产量、品质及效益的影响 总被引：1，自引：0，他引：1
以南粳9108为试验材料,研究了不同稻作方式对优质稻品种产量、品质及效益的影响。结果表明,不同稻作方式实收单产由高到低依次为钵苗机插、毯苗机插、稻鸭共作和稻虾共作;整精米率由高到低依次为稻鸭共作、稻虾共作、钵苗机插和毯苗机插,垩白粒率及垩白度表现为钵苗机插最高、稻鸭共作最低,稻田综合种养模式稻米的外观品质表现较好。稻田综合种养模式降低了南粳9108稻米的蛋白质含量和直链淀粉含量,适当提高了稻米的胶稠度,稻米RVA特征谱表现出消减值降低和崩解值提高,改善了蒸煮食味品质。经济效益由高到低依次为稻虾共作、稻鸭共作、钵苗机插、毯苗机插,综合种养模式的效益明显高于单一种稻模式。 相似文献
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为了缓解稻田共作出现的“重渔轻稻”矛盾,以南粳9108和丰优香占为供试品种,以稻麦轮作（R-W）为对照,设置稻鸭共作-紫云英轮作（RD-Mv）、稻虾轮作（R-C）两种稳稻种养模式,通过综合栽培措施调控构建稳产水稻群体（产量>7.5 t/hm2）,研究不同稻作模式下水稻产量形成和周年经济效益。结果表明,与R-W相比,RD-Mv能显著提高水稻产量,平均提高7.17%,R-C产量与R-W相当,RD-Mv增穗增产,R-C增粒稳产。RD-Mv和R-C能增加水稻剑叶SPAD值,提高叶面积指数,较R-W分别增加9.97%~33.45%和12.78%~39.78%,差异显著。RD-Mv和R-C提高了水稻地上部干物质积累量,主要增加了播种至分蘖中期的积累量。RD-Mv和R-C的光合势和分蘖中期前的群体生长率显著高于R-W,分蘖中期后的群体生长率无显著差异。周年效益方面,R-C利润高,产投比达3.12,RD-Mv利润有所提高,但产投比仅2.29,低于R-W的2.51。综上,稻鸭共作-紫云英轮作和稻虾轮作均能稳产增收,叶绿素含量高、叶面积指数高、光合势好、前期干物质积累多且群体生长好是其增产稳产的原因。 相似文献
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《Journal of Crop Improvement》2013,27(1-2):229-247
SUMMARY The livelihood and calorie needs of large populations based in developing countries is dependent on rice cultivation. More than three billion people consume rice as a staple food. To meet the future demands of the human population, innovative tools such as genomics are being used to improve rice yield increase, for the incorporation of stress resistance/tolerance in rice varieties, and for the improvement of the nutritional quality of rice. These new tools include: sequencing, large-scale analysis of expressed sequence tags, high throughout microarray analysis and genetic transformation. Rice now serves as a model for a science based crop design for the agronomic, nutritional, and economic benefit of farmers. This article discusses the use of biotechnology as a tool to improve the rice plant for the benefit of mankind. 相似文献
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介绍了2009—2011年将乐县开展水稻高产创建活动所取得的实效及组织措施,通过加强技术指导与培训、抓好＂五新工程＂等措施来推广高产优质的水稻品种和水稻高产群体调控增产增效措施,从而实现增产增收的目的。 相似文献
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对山区马铃薯—再生稻耕作制进行探讨。结果表明,马铃薯—再生稻耕作制既增产又增收。每667m2马铃薯产量达1 658 kg,再生稻两季产量达877.3 kg,产值达5 021.5元,纯收入达3 887.5元,比单季稻和单种再生稻效益显著提高。文章对其主要栽培技术进行了总结。 相似文献
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Sipaseuth J. Basnayake S. Fukai T.C. Farrell M. Senthonghae Sengkeo S. Phamixay B. Linquist M. Chanphengsay 《Field Crops Research》2007
Rice is a major source of food for more than 2.7 billion people and planted on nearly 130 million hectares in which 10% is subjected to low temperature problems. Dry season (DS) rice cropping has been expanding in the high altitude lands in Asia and the low temperature is one of constraints to rice production. This study aims to quantify the potential for growing irrigated rice in DS, particularly in high altitude areas in northern Lao PDR where temperatures are low and pose problems for seedling establishment. Research focused on identifying sowing times to avoid the detrimental effects of low temperature, the optimal seedling age for transplanting, the potential of plastic covers and half burnt paddy husk layer to protect nursery seedbeds from low temperature and varieties suitable for this environment. Studies were conducted over 5 years and were examined at six locations. In two locations, where temperature was favorable for rice production throughout the DS, time of sowing was not critical. In higher altitude areas in northern Lao PDR, however, low temperature caused establishment problems in nurseries. In these areas, mid-November sowing before the onset of winter reduced the low temperature effects on seedling establishment while sowing in mid winter (December and January) increased the risk of failure. There were no significant effects of seedling age (25-, 35- and 45-day old) for transplanting on yield for DS rice. Using clear plastic to cover the nursery increased minimum temperatures on average by about 4 °C, which improved seedling growth and resulted in higher grain yield. The mean minimum temperature of 12 °C for 30 days after seeding is critical and temperature below 12 °C resulted in high risk of crop failure due to poor germination, poor seedling growth or insufficient seedlings. Rice needs to be sown at times where the mean minimum temperature exceeds 12 °C or plastic covers are required to protect seedlings. The current popular varieties did not show significant tolerance to extreme cold temperature. 相似文献
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烟草是我国重要的经济作物。连作种植作为烟草的主要栽培方式，具有节省劳力、劳作时间、生产成本等优势，但烟草长期采用连作会导致土传病虫害增多、杂草群落较为单一、土壤肥力和微量元素下降等诸多问题，降低了烤烟产量和烟叶品质；加上烟草连作中烟叶采收后，农田基本处于闲置状态，造成土地资源浪费，加重了烟粮争地的矛盾，导致烟农收入减少。针对烟草连作栽培所出现的问题，笔者提出了“烟草-水稻”轮作耦合养鸡养鱼的综合种植与养殖模式。该模式在烤烟采收后，将水稻直接种植在烟垄的两侧，实现烟垄免耕，节省了水稻生产成本。水稻种植后，垄肩保持湿润无水，便于鸡捕食等活动，垄沟灌水便于水稻生长和养鱼，通过鸡鱼在稻田活动可防控田间病虫草害，鸡鱼粪便可培肥土壤，利于降低农药和肥料用量，进而改善农田生态环境，产出优质的稻米、鸡和鱼等农产品，显著提高稻作经济效益，并实现烟田土壤改良和烟农收入增加的双重目标。本文结合“烟草-水稻”轮作耦合养鸡养鱼的具体实施情况，论述了该模式的技术要点、综合效益和发展展望等，以期为“烟草-水稻”轮作下开展养殖提供技术借鉴。 相似文献
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Tuyet Thi Anh Truong John Fry Phu Van Hoang Hoang Huy Ha 《Paddy and Water Environment》2017,15(4):931-941
The consumption of energy inputs in agricultural production has been increasing rapidly during the past decades. However, given the limitations and costs of non-renewable energy, increasing production while using the least energy possible has become a major concern of most nations. Prompted by this concern, we conducted a face-to-face survey of 90 farming households in Thai Nguyen Province, Vietnam, to find out how energy is being used in agriculture and, specifically, in their rice production. Through analysis of energy input–output balances, combined with economic efficiency analysis, a comparison was made of conventional and SRI methods of rice production. The study found that applying the SRI method can save around 23% of energy inputs, while increasing energy outputs by 11%. Economic benefits per hectare also rise by more than 8 million dong (USD 364) compared to those under the conventional cultivation system. The study also showed conflicts between the energy and economic balances for manual compared with machine ploughing operations. This study contributes to providing an overview of energy consumption in rice cultivation at the household level. Its findings can help stakeholders to assess current policies and make better decisions on the uses of energy in agricultural production. In addition, the comprehensive approach taken here to analysing energy use and efficiency could expand the analysis and comparison of energy uses at sectoral or activity level—still a new field in Vietnam and many other countries. 相似文献
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《Journal of Crop Improvement》2013,27(1-2):93-130
Abstract Despite a significant increase in food production during the last century, world production will need to be doubled or tripled by the year 2050 to meet the needs of an expected 10 billion global population. Fortunately, a second revolution in agriculture appears to be taking place from advances in biotechnology. Worldwide in 1999, about 40 million hectares of transgenic plants were grown, and this area is expected to increase significantly for years to come. Rice (Oryza sauva L.) is the staple food of the majority of 3.5 billion people in Asia. Increases in population in the rice growing regions of Asia will require 70% more rice in 2025 than is consumed today. In addition, rice, in its milled form, is poor in essential amino acids and a range of vitamins and micronutri-ents, which creates malnutrition. With the increasing number of genes discovered in plants and other organisms, transgenic research is being utilized to improve agronomic traits of rice, such as resistance to biotic and abiotic stress, and to increase photosynthetic efficiency which collectively increase yield. Research is also moving toward improvement of grain quality traits, including amino acids, micronutrients, and vitamins. Genome sequencing and the techniques for rice transformation have been developed. Thus, collaborative efforts in genomics, transformation, and molecular breeding of rice are expected to lead to a significant contribution to global food security. In this article, we review the current status of genetic improvement of rice. Improved methods for transgene expression in rice and potential modifications that will significantly improve yield and grain quality of rice are also discussed. 相似文献
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Weihua JiangXiaojing Jiang Jianren YeQiang Fu Yongbin FengJu Luo Zhaojun Han 《Crop Protection》2011,30(2):130-133
Super rice has the potential to deliver very high yields but is also susceptible to attack by the striped rice stem borer, Chilo suppressalis. In this study, surveys and field trials were performed to examine this problem and efficient ways were found to lower the borer’s population density. It was found that larger super rice plants provided more refuges for borers to evade insecticide contact and had a longer growth period allowing borers to complete their larval development in an intact environment. The current cultivation regime was shown to favour outbreaks of borers. Super rice is harvested leaving tall field stubbles until the following growing season, thus providing food and cover in which borers may successfully overwinter. We found that borer larvae were distributed to a greater height in the plants of super rice than in common rice, making control through agricultural operations more feasible. Burning fields after harvest, which killed 84.5% of borers, seemed the best remedy, though this practice is forbidden in China for ecological reasons. Leaving short stubbles followed by appropriate treatment of the rice straw killed 74.0% of the borer population. In addition, spring irrigation after the pre-pupation dispersal movements of borers killed more than half of the overwintering population. Pre-winter rotary tillage had little effect on borer numbers but enhanced the population reduction effect of irrigation the following spring. Based on the results obtained, efficient control of borers on super rice can be achieved by harvesting leaving short stubbles, followed by rotary tillage and spring irrigation. This regime can reduce the borer population by more than 98%, minimising chemical use and maximising use of a reduced agricultural workforce. 相似文献
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在分析我国大米处于适度进口的基础上,指出了我国大米安全的若干风险,即国内大米消费人口有增无减,国内大米生产增长空间不大,水资源、土壤环境等影响水稻生产的问题仍然严重,"镉大米"成为大米质量安全的痛点,粮源、贸易与禁运风险存在过或可能再度发生,大米进口毕竟有了量的突破,大米进口集中在个别国家可能导致真需粮时无粮,低价大米长期流入国内不利于保护稻农利益,大米实际进口量大于统计进口量可能误导决策。 相似文献