Integrated Rice-duck Farming Research Articles

Effects of integrated rice-duck farming on weed pressure, herbivore-predator interactions and economic benefits

ABSTRACT This study was conducted to evaluate whether conventional farming can be replaced by a lower chemical pollution farming system, integrated rice-duck farming in a suburban agricultural area in northern Zhejiang, Southeast China. We comprehensively assessed the impacts of integrated rice-duck farming on weeds and herbivorous insects along with their natural enemies during the rice-growing season. We found that the rice-duck system effectively controlled weeds within the paddy fields. Nevertheless, the abundance of herbivores, particularly planthoppers and leafhoppers was increased in the duck-roaming paddy fields compared to the control and conventional fields, indicating the inefficiency of the rice-duck system in the control of rice main herbivore pests. Rice-duck farming significantly reduced the abundance of predators, especially spiders and dragonflies, therefore an ‘enemy-free space’ was created for herbivores which might be responsible for the observed herbivore increase in the rice-duck fields. Despite the inefficiency of rice-duck farming in the control of rice main herbivore pests, the net income of the rice-duck treatment with an organic certification was 7.6 and 1.4 times higher compared to the conventional and control treatments, respectively. In the view of the favourable results obtained in this study, the integrated rice-duck farming system might be suggested as a high economic return organic farming method suitable for modern farmers.

Effects of integrated rice-duck farming system on duck carcass traits, meat quality, amino acid, and fatty acid composition

Integrated rice-duck farming (RD) system, which aims to improve the welfare of ducks, has gained popularity in Asian countries. However, the effects of RD system on the carcass and quality traits of duck meat have not been evaluated. Here, a paddy field experiment was conducted to examine the effects of RD system on the carcass and quality traits of duck meat. A total of 180 Jinding ducklings (7 days old) were randomly divided into 2 rearing systems of floor pen rearing (FPR) system and RD system. After 11 weeks, 12 ducks from each rearing system (6 males and females each) were used for carcass traits, meat quality, amino acid, and fatty acid analyses. The results showed that ducks reared in the RD system had higher carcass yield and intramuscular fat content (P < 0.05) than those reared in the FPR system; however, ducks reared in the RD system had lower protein and moisture content (P < 0.05). Additionally, the concentration of essential amino acids, including Tyr, Val, Met, Phe, His, Ala, Arg, and Pro, was higher in the breast muscle of ducks reared in the RD system than those reared in the FPR system. Furthermore, higher saturated fatty acid (C12:0, C14:0, C16:0, C18:0, and C21:0), monounsaturated fatty acid (C16:1, C18:1, and C18:1T), and polyunsaturated fatty acid (C22:2, C18:2n-6, and C22:6n3) content was recorded in the breast muscle of ducks reared in the RD system than those reared in the FPR system (P < 0.05). Taken together, our results indicated that the RD system improved the carcass traits, intramuscular fat, essential amino acids, and polyunsaturated fatty acids profiles of the ducks. These findings suggest that the RD system is an effective strategy to improve the welfare and meat quality of ducks.

Can integrated rice-duck farming reduce CH4 emissions?

Integrated rice-duck farming (IRDF) has proven to decrease methane (CH4) emissions due to increased dissolved oxygen caused by duck bioturbation. The duck bioturbation, however, also causes many bubbles of CH4 that were overlooked in previous studies. Therefore, it is uncertain whether IRDF could decrease CH4 emissions. We hypothesize that the effect of IRDF on CH4 emissions is related with the intensity of duck bioturbation. We simulated duck's disturbance (trampling and foraging) by stirring and aerating the surface soil in flooded rice fields. Three treatments were disturbed with an interval of 12h (D12), 24h (D24), and 48h (D48), respectively, with non-disturbance as the control (CK). CH4 emissions as bubbles during the disturbance period (CH4-A) were investigated. Besides, CH4 emissions were investigated every 2h (CH4-B), which lasted for 4days during the rice elongation stage. Compared with CK, D12, D24, and D48 decreased CH4-B emissions by 17.1%, 14.0%, and 10.1%, respectively. However, the CH4-A emissions under D12, D24, and D48 were equivalent to 14.2%, 14.0%, and 11.9% of CH4 emissions under CK, respectively. On the whole, simulated duck bioturbation had limited effects on the reduction of total CH4 emissions.

Integrated Rice-Duck Farming Decreases Soil Seed Bank and Weed Density in a Paddy Field

Coupled cropping-breeding modes have been highly recommended due to their ecological and sustainable nature. Integrated rice-duck farming is a typical ecological planting system in rice paddy fields and has been widely popularized in Asia where a considerable area of cropland has been planting rice. In this study, two experimental treatments of turbid water or rice-duck treatment were established to compare with the control and a conventional treatment in absence of ducks. The turbid water treatment imitated the muddying effect by duck activities with the trampling and foraging effects excluded, while the rice-duck treatment included all of the mentioned effects by raising ducks in rice paddy field. Results showed that the rice-duck treatment significantly reduced soil seed bank density by more than 40% and the figures under the turbid water treatment were 18.2% and 30.5%, accordingly, in the early and late rice growing seasons. Moreover, the rice-duck treatment significantly altered the vertical distribution of soil seed bank by substantially declining the seed density in the topsoil (0–5 cm). Changes in soil seed bank density considerably contributed to the declines in above-ground weed density because a significant correlation was detected between the soil seed bank density in the early season and the weed density in the late season. Our results of declined soil seed bank and weed density in integrated rice-duck farming imply that this system is highly efficient as a biological pathway for controlling weeds.

Quantifying the spatiotemporal dynamics and multi-aspect performance of non-grain production during 2000–2015 at a fine scale

In recent years, large quantities of cultivated land in China have been converted to non-grain production. There is a growing need to understand the spatiotemporal dynamics and multi-aspect performance of non-grain production to aid further agricultural development and ensure grain security. Multi-temporal high-resolution aerial photographs were used to investigate the trends of four categories of non-grain production (pond farming, duck rearing, nursery plantation and vegetable production) in the Tongxiang region of China from 2000 to 2015. Spatial analysis was then utilized to identify spatial autocorrelation and hotspots for different non-grain production categories. Finally, environmental and economic indicators were applied to assess the performance of different non-grain production categories from the perspective of environmental impact, economic benefits and grain security and to link the performance to the differences in dynamics. The results showed that the non-grain production in Tongxiang increased by 2460.68 ha from 2000 to 2015. The non-grain expansion in different periods was closely related to the central and local policy orientation. Environmental and economic analyses revealed that nursery plantation and pond farming consistently dominated in Tongxiang due to their low investment requirements, low environmental pressure and relatively high economic profit. All non-grain production categories exhibited strong spatial autocorrelation in 2000–2015, as evidenced by spatial analysis. Conspicuous regional disparities were also observed in the hotspots of different non-grain production categories, in part due to local traditions and the clustering effect. Non-grain production activities generated more pressure on the local environment than rice plantation despite high economic benefits. Furthermore, the expanding non-grain production in rural China will lead to an overestimation of grain outlook and jeopardize national grain security in the long run. Eco-agricultural systems, such as integrated rice-duck farming systems, could increase the likelihood of an economic and ecological win-win situation between non-grain production and grain cultivation.

Integrated rice-duck farming decreases global warming potential and increases net ecosystem economic budget in central China.

Over the past decades, many attempts have been made to assess the effects of integrated rice-duck farming on greenhouse gas emissions, use efficient of energy, soil fertility, and economic significance. However, very few studies have been focused on the effects of the farming on net ecosystem economic budget (NEEB). Here, a 2-year field experiment was conducted to comprehensively investigate the effects of ducks raised in paddy fields on CH4 and N2O emissions, global warming potential (GWP), rice grain yield, and NEEB in central China. The experiment included two treatments: integrated rice-duck farming (RD) and conventional rice farming (R). The introduction of ducks into the paddy fields markedly increased the rice grain yield due to enhanced tiller number and root bleeding rate. RD treatment significantly elevated the N2O emissions (p < 0.05) but decreased CH4 emissions (p < 0.05) during rice growing seasons compared with R treatment. Analysis of GWP based on CH4 and N2O emissions showed that compared with R treatment, RD treatment significantly decreased the GWP by 28.1 and 28.0% and reduced the greenhouse gas intensity by 30.6 and 29.8% in 2009 and 2010, respectively. In addition, RD treatment increased NEEB by 40.8 and 39.7% respectively in 2009 and 2010 relative to R treatment. Taken together, our results suggest that the integrated rice-duck farming system is an effective strategy to optimize the economic and environmental benefits of paddy fields in central China.

Integrated rice-duck farming mitigates the global warming potential in rice season

Integrated rice-duck farming (IRDF), as a mode of ecological agriculture, is an important way to realize sustainable development of agriculture. A 2-year split-plot field experiment was performed to evaluate the effects of IRDF on methane (CH4) and nitrous oxide (N2O) emissions and its ecological mechanism in rice season. This experiment was conducted with two rice farming systems (FS) of IRDF and conventional farming (CF) under four paddy-upland rotation systems (PUR): rice-fallow (RF), annual straw incorporating in rice–wheat rotation system (RWS), annual straw-based biogas residues incorporating in rice–wheat rotation system (RWB), and rice-green manure (RGM). During the rice growing seasons, IRDF decreased the CH4 emission by 8.80–16.68%, while increased the N2O emission by 4.23–15.20%, when compared to CF. Given that CH4 emission contributed to 85.83–96.22% of global warming potential (GWP), the strong reduction in CH4 emission led to a significantly lower GWP of IRDF as compared to CF. The reason for this trend was because IRDF has significant effect on dissolved oxygen (DO) and soil redox potential (Eh), which were two pivotal factors for CH4 and N2O emissions in this study. The IRDF not only mitigates the GWP, but also increases the rice yield by 0.76–2.43% compared to CF. Moreover, compared to RWS system, RF, RWB and RGM systems significantly reduced CH4 emission by 50.17%, 44.89% and 39.51%, respectively, while increased N2O emission by 10.58%, 14.60% and 23.90%, respectively. And RWS system had the highest GWP. These findings suggest that mitigating GWP and improving rice yield could be simultaneously achieved by the IRDF, and employing suitable PUR would benefit for relieving greenhouse effect.

Community-Based Organic Agriculture in the Philippines

This paper explores institutional mechanisms that might be required to boost both organic agriculture and rural development in the Philippines. Special attention is paid to community-based organic agriculture as a pathway to rural development. The Philippines has two decades of experience of community-based natural resource management. Unlike public natural resources such as forests, watersheds or fisheries, however, the community-based organic agriculture programme is intended to deal with the private property regime. Thus, if the programme is to be successful, agrarian land reform must continue. Integrated rice–duck farming is among the suitable and viable options for organic agriculture, given that rice is a major agricultural crop and duck meat is popular in the Philippines. Area-based organic food certification systems need to be formulated and a government–farmers partnership should be forged to facilitate farmers' access to domestic and international organic food markets.

Communitarian cooperative organic rice farming in Hongdong District, South Korea

It is often questioned whether sustainable agriculture by smallholder farmers can phase out conventional agriculture. This paper draws on a case study of organic rice farming in Hongdong District, South Korea, and provides insights into communitarian cooperative organic farming, a collective organic farming model. Various organic farming practices (e.g. integrated rice–duck farming) have been collectively adopted by small-scale rice farmers in Hongdong since 1994. Organic rice farming in Hongdong is characterised by place-based cooperatives, community-supported agriculture, and strong community leadership. Hongdong has demonstrated that communitarianism and smallholder cooperatives can work for each other complementarily and therefore that communitarian organic farming through smallholder cooperatives is highly operational. The Hongdong organic farming model is of great relevance to other parts of rice-growing Asia, which are dominated by smallholding farmers, in terms of the twin goals of food security and food safety.

An institutional and policy framework to foster integrated rice–duck farming in Asian developing countries

Asia has accounted for the vast majority of the world's rice and meat-duck production. In the integrated rice–duck farming (IRDF) system, ducklings are released into rice paddies in order to maximize the use of renewable resources in a closed-cycle flow of nutrients during rice vegetation periods. Rice–duck farming used to be widely adopted in tropical and subtropical eastern Asian countries, but has remained unpopular in the wake of prevailing agricultural productivism characterized by specialization, intensification, mechanization and excessive dependence on agrochemicals. This paper sets out institutional pathways that can redevelop IRDF in Asia. These include organic food certification systems, organic farmers' cooperatives, community-wide organic farming, localized technical extension and educational services, and between-farm rice–duck integration. A comprehensive package of these institutional tools would further expedite the expansion of IRDF particularly in low-income Southeast Asia where the rice or duck farming landscape is overwhelmingly dominated by smallholders.

Theory and reality of integrated rice–duck farming in Asian developing countries: A systematic review and SWOT analysis

The integrated rice–duck farming (IRDF), in which ducks feed on insects and weeds in paddies and fertilise rice plants, has been a flagship of Asian sustainable-agriculture movements. Nevertheless, IRDF is not spreading rapidly enough to the extent to which it becomes a successful alternative agriculture. This paper undertakes a systematic review of a collection of experimental IRDF studies in order to derive an insight from the divergent experimental settings and findings. The paper also identifies the strengths and weaknesses of, opportunities for and threats to IRDF from the perspective of IRDF farmers, using the expert elicitation method. Five IRDF expert farmers from each of South Korea, Malaysia and Vietnam were interviewed for this purpose. The experimental studies and the expert farmers concurred that the most recognisable empirical strength of IRDF is the synergy of rice and ducks. It was found that the establishment of organic food certification systems provides an opportunity for IRDF to grow. On the other hand, labour-intensiveness was found the most challengeable weakness of IRDF. In parallel, labour shortage in rural areas was found as a serious threat to IRDF. It appears that the weaknesses and threats are more influential than the strengths and opportunities to shaping the adoption of IRDF. In order to make IRDF economically more feasible, the non-market ecological benefits of IRDF in mitigating land degradation and global warming can and should be internalised through appropriate policy instruments.

Effect of integrated rice-duck farming on rice canopy structure index

水稻株型结构能够影响水稻的产量和品质。稻鸭共作能否对水稻株型结构产生影响, 目前这方面的定量研究还很少。本研究通过田间对比试验, 探讨了稻鸭共作与常规稻作两种处理对水稻分蘖期和齐穗期的部分株型结构指标的影响。结果表明, 与常规稻作方式相比, 稻鸭共作使水稻基部宽度呈减小趋势、冠层幅度呈增大趋势, 最终使植株松散度显著增加, 分蘖期和齐穗期增幅分别为12.2%和42.3%。稻鸭共作使水稻倒3叶和倒4叶的叶长、叶开角和披垂度减少, 使剑叶和倒2叶的叶长、叶开角和披垂度增大, 从而使水稻呈上披下挺的株型结构, 并使叶面积主要分布于上部叶片。稻鸭共作使水稻植株的基叶高呈增加趋势, 在齐穗期与常规处理达到显著性差异。稻鸭共作有利于水稻生育前期和中期的茎蘖合理发展, 而且在后期可促进水稻上部功能叶片的生长, 这在一定程度上有利于水稻高产的形成。

Effect of Integrated Rice-Duck Farming on Rice Yield, Farm Productivity, and Rice-Provisioning Ability of Farmers

The feasibility of the rice-duck system of rice production, practiced in some East Asian countries, is studied in Bangladesh as a sub-project of the Poverty Elimination Through Rice Research Assistance (PETRRA). The Bangladesh Rice Research Institute (BRRI) implements the sub-project in collaboration with two NGOs, FIVDB and BDS, in the northeastern (greater Sylhet) and southern (Barisal) regions of the country. Each demonstration trial, conducted in the field of the farmers, is treated as a replication. In these trials, the rice-duck system is compared with the methods of growing rice solely, as traditionally practiced by the farmers in Bangladesh. Evaluation of the activities carried out under the PETRRA sub-project shows that the rice-duck system is not only feasible, but also economically rewarding for the farmers. The yield of rice is, on average, 20% higher in the rice-duck system than the traditional rice system (sole rice), thereby ensuring about 50% higher net return and rice-provisioning ability. The ducks in the rice-duck fields control weeds and insects very effectively; as a consequence, labor and pesticide costs for controlling weeds and insects are minimized and the soil health is improved. The ducks provide another source of added income for the farmers. In view of the favorable results obtained in the study, it might be suggested that the rice-duck system be spread throughout the country as an income-generating activity for the resource-poor farmers.