- Agronomic: rice
- Animals: fish
- Animal Production: manure management
- Crop Production: fertigation, irrigation, organic fertilizers, contour farming, terraces
- Education and Training: demonstration, networking, on-farm/ranch research, youth education
- Energy: energy conservation/efficiency
- Farm Business Management: new enterprise development, value added
- Production Systems: organic agriculture, permaculture
- Sustainable Communities: local and regional food systems, sustainability measures
It is known that rice can be successfully grown in Vermont. However, rice farming can be an extremely water-intensive farming practice. We seek to understand how a variable water supply in rice paddies affects growth and grain yield at 2 Vermont farms. We will manipulate water level using 4 water treatments (control, saturated soil, low-water level, and mid-water level) for 4 temperate rice strains. We will use a randomized block design with 10 replicates. We will estimate plant vigor, record the panicle formation date, maturation date, and estimate percent sterility per panicle post-harvest as a measure of cold resistance. The harvested grain will be dried, threshed, and dehulled to quantify total grain yield of each water treatment and cultivar. We will use ANOVA to analyze the effects of water level on the size and survival of each life history stage (transplant, vegetative, reproductive, ripening) and the final grain yield of the 4 cultivars at each site. We will collect rainfall and temperature data at each farm to detect any significant climatic differences. We will also monitor wildlife in the rice paddies to quantify biodiversity indices and assess the ecosystem services provided by these constructed wetland habitats. The project is timely and necessary, as farmers must prepare for future changes in the climate, including an increased probability of severe weather events, including flooding and drought. The project results will inform northeastern rice farmers how to utilize subprime agricultural land to grow rice and increase farm income in a changing climate.
Regular farm tours will be held to demonstrate the progress of the project. Workshops will be planned to give more in depth information and skills and presentations of the results are planned at the NOFA-VT Winter conference. Results will also be posted at University of Vermont websites and on the NOFA-VT website.
Project objectives from proposal:
Description of problem and significance
Climate change, along with increases in temperature and severe weather events, has profound implications for agriculture in the northeastern U.S. (Hoffman and Smith, 2011). Rice feeds more than 3 billion people worldwide (IRRI, 2010) and receives 24-30% of the world’s freshwater resources (Bouman et al., 2007). We will investigate how a variable water supply affects rice growth and grain yields, therefore informing northeastern rice farmers how to best prepare for climate change. We will examine how 4 temperate rice strains respond to variable water levels in 2 different Vermont climates (Whole Systems Research Farm in Moretown, VT, and JM Plants and Produce in Shelburne, VT).
Previous research has demonstrated that rice can be successfully grown in the northeastern US and has the potential to become an important commercial crop (Akaogi, 2009). However, growing a water-intensive crop such as rice presents important future challenges in the face of climate change and variability in the water supply. Water provides an essential plant resource, but is also a thermal sink with the ability to retain heat and release it slowly, thereby extending the rice-growing season. However, a combination of higher temperatures and increased evaporation due to climate change will cause more intense and frequent droughts in the northeastern US, which will lead to a reduction in the availability of water for input into agricultural systems (Hayhoe et al., 2006).
Climate change models predict more severe weather events, including an increase in flooding and erosion. Rice paddies are wetlands that perform important, but poorly understood, ecosystem services by increasing biodiversity in the landscape, moderating climate, controlling flooding and erosion, and capturing nutrients to prevent excess runoff (Hansson et al., 2005; Bouman et al., 2007). In an effort to begin to estimate the biodiversity within rice paddies, we will survey the constructed wetlands for aquatic wildlife. We will quantify biodiversity as a biotic index, a scale value that quantifies the quality of an aquatic environment by indicating the types and numbers of species present (Simon et al., 2000).
Growing rice sustainably in the northeast brings multiple benefits to the farmer and environment. First, rice is a staple food crop that feeds over half of the human population around the world (IRRI, 2010) and is an adaptable crop that can grow in a variety of habitats. Rice has not been commercially grown in the northeastern US, even with the availability of cold-hardy varieties. Thus, this important grain must be imported, although there is an opportunity to grow rice locally. Because rice is such an important crop, local growers would benefit economically from the sale of local grain. There is a great opportunity for outreach, as it is a new grain crop for the area and there is much information to share and still much to learn. The major opportunity for growing rice in the northeast is the ability to diversify and add value to farms by utilizing marginal soils without transitioning prime agricultural land.
Linda and Takeshi Akaogi have been growing rice on their southern Vermont farm since 2006. A rice paddy system consists of a complex wetland habitat, including (1) the rice paddy, which is a temporary pool; (2) the reservoir, which is a permanent pool; and (3) the irrigation channels between the paddy and reservoir and the outlets. The Akaogis identified 5 temperate rice varieties that produced seed in 2007. After collaborating with rice researchers at Cornell University in 2008, the Akaogis grew 25 varieties that produced seed, selecting 3 varieties for experimental trials. These 3 varieties yielded an average of 6500 lbs/acre, which is comparable to strains from northern Japan and twice the average yield for wheat (Akaogi, 2009). The Akaogi Farm employed traditional intensive water use practices in growing rice in their paddies.
Sustainable water use management strategies for rice farmers is a top priority of the International Rice Research Institute, and they are investigating management strategies for rice farmers to cope with the effects of climate change (Wassmann, 2007). To date, the IRRI recommends that farmers establish efficient irrigation infrastructure, coupled with water-saving techniques. Good nutrient management with alternate wetting and drying are also recommended as a sustainable management practice (IRRI, 2010). However, a greater understanding of the adverse effects of variability in the water supply on the sustainability of rice production, environment, and ecosystem services is needed (Bouman et al., 2007).
We will build off the methods outlined in the Rice Growing Manual for the Northeast USA (Akaogi, 2009) by experimentally quantifying how varying water use during each stage of the rice plant’s life cycle (i.e., seedling, vegetative, reproductive, and ripening phases) affects annual crop yield. Our main objective is to determine the optimum water levels that will both conserve water resources and maintain yields for 4 temperate rice varieties adapted to the northern VT climate. We will conduct these experiments at the Whole Systems Design Research Farm (WSRF) and the JM Plants and Produce Farm during the 2012 growing season (April – September). We will utilize the 2-year-old constructed rice paddies at WSRF. We will also grow a series of plants in 5-gallon buckets following guidelines in the Rice Growing Manual (Akaogi, 2009). JM Plants and Produce currently does not have constructed rice paddies, so we will exclusively utilize the 5-gallon bucket method and design for future rice paddy construction. We anticipate that this research will open the door to many other questions regarding growing rice sustainably in the northeastern US.
The rice trials will take place at the Whole Systems Design Research Farm in Moretown, VT (N44 15’3.49" W 72 45’20.18") and JM Plants and Produce Farm in Shelburne, VT (N 44° 23′ 21.81" W 73° 12′ 46.96"). We will manipulate water levels in 2 constructed rice paddies and rice grown in 5-gallon buckets to increase our statistical sample and power to detect differences among water treatments. We will have 4 water treatments with 10 replicates per treatment. Organic, high-N fertilizers (e.g., duck and chicken manure) will be added to the paddies via an irrigation system (“fertigation”) at regular intervals. Fertigation presents a unique opportunity to harness the nutrients available in water on-farm and put them to productive use while reducing their ability to enter local watersheds. Rice (a heavy feeding crop) can grow in poor subsoil if fertigated. We hope this project will instigate interest in using marginal agricultural soils on working farms to grow rice.
Due to the differences in climate at each site, we will also grow 4 different rice cultivars as recommended by Vermont rice grower Takeshi Akaogi (Table 1). Oryza sativa var. Akitakomachi, Matsumae, and Hayayuki are all varieties cultivated from northern Japan and bred for cold tolerance and early maturity (Akaogi, 2009). M-202 is one of the earliest maturing varieties from California. These cultivars have been successfully grown and have yielded grain at the Akaogi farm in southeastern VT. We will measure the growth, first heading date, date of maturity, cold tolerance and yield of each strain to compare differences among rice-growing potential in the Mad River and Champlain Valleys of Vermont.
During the growing season, we will manipulate water level of rice growing in 5-gallon buckets in a series of 4 experimental water treatments (Table 2). The control treatment follows water level guidelines outlined in the Rice Growing Manual (Akaogi, 2009). The buckets will be set-up as a randomized block design (Figure 1) to reduce variance in the data, as variability within each block is less than the variability of the entire sample (Gotelli and Ellison 2004). Treatments will be randomized within blocks, and each block will receive each water treatment replicate. We will gather data on plant vigor, cold-hardiness, panicle formation, maturation date, total grain yield, biodiversity of rice paddies, temperature and rainfall in order to assess difference among rice varieties, farm location, and water level treatments.
JM Plants and Produce has a holding/warming pond, but currently does not have rice paddies. Therefore, we will grow all rice in buckets here and assess the site for future rice paddy construction. The rice paddies at the WSRF are fertigated by a gravity-fed system, so water levels are more difficult to manipulate as precisely as the bucket treatments. However, the upper paddy tends to maintain drier conditions as it drains into the lower paddy, which maintains more saturated conditions (Figure 2). We will measure water input and output into the WSRF constructed paddies by calculating the small pool’s capacity and track how many times it drains through the growing season.
We will estimate plant vigor by counting stem number of each treatment plant and consistently assess survival of each treatment plant. We will record panicle formation date, maturation date, and percent sterility per panicle post-harvest as a measure of cold resistance. The harvested rice will be divided into water and cultivar treatments and dried on site, and then threshed and dehulled off site in order to access processing equipment. We will quantify total grain yield of each water treatment and cultivar. We will also collect weekly rainfall and temperature data at each farm using a temperature and rain gauge.
We are also interested in quantifying biodiversity indices and assessing the ecosystem services provided by these constructed wetlands. We realize that data collected from a single growing season will be insufficient to fully access the biodiversity within the paddies, but it will be helpful in providing baseline data. We will estimate the index of biotic integrity (IBI) based on crayfish, fish, and amphibian assemblages in small, shallow wetland habitats of less than 5 ha (Simon et al. 2000). We will use a 3m common sense minnow seine with 3 mm bar mesh to collect amphibians, crayfish and fish from each of the constructed wetlands in the WSRF paddy system. We will conduct 3 sampling trials between mid-June and mid-August.
The major question is whether there are differences in rice performance and grain yield among water level treatments. We are also interested in detecting differences among strains in dealing with water stress and between farms, which are located in different growing zones. To do this, we will use analysis of variance (ANOVA) to analyze the effects of water level on the size and survival of each of the 4 life history stages and the final grain yield of the 4 cultivars at each site. Analyzing each life history stage separately will provide information on when water is most limiting during the rice life cycle. We will set the treatment effect in the ANOVA model as fixed and the block effect as random (Gotelli and Ellison 2004). We will also use ANOVA to examine climatic differences (temperature and rainfall) between the 2 farms.
We will create a database of aquatic wildlife collected from the paddies. In the past, the Akaogi farm has focused on amphibian use of the rice wetlands. They have monitored seasonal changes, number of individuals, and have researched information on amphibian life cycles and habitat requirements. Unfortunately, these data have not been made available in a report. We will assess biodiversity within the WSRF rice fields and obtain the information gathered at the Akaogi farm to generate a scientific report on how sustainable rice agriculture in the northeast can enhance the biodiversity of the region. Together, this information is not only imperative in advising the construction of new rice fields, but is also informative in achieving conservation objectives for each species.