Ricardo RadulovichUniversity of Costa Rica | UCR · Department of Biosystems Engineering
Ricardo Radulovich
PhD
About
49
Publications
88,241
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999
Citations
Citations since 2017
Introduction
Originally an agricultural water scientist, to secure more water for food production I now also work at sea and in lakes, where the water is. We work mainly advancing and promoting aquatic food production alternatives for development (seaweed farming, aquatic agriculture, low-trophic fish mariculture). As work in water requires integration, aquatic food production systems include relations with fisheries and ecosystem services, as well as strong links to climate change and to agriculture.
Additional affiliations
August 1991 - June 1994
Position
- International Project Coordinator
Description
- Coordinated rural development project in Nicaragua, Honduras, El Salvador and Guatemala with base operation in Costa Rica.
July 1989 - June 1991
July 1985 - present
Position
- Professor
Description
- Univ. of Costa Rica is my home institution. I have worked elsewhere (Cornell Univ., CATIE, Zamorano, UNDP). Besides my research on aquatic food production and extension work on climate change, we are busy changing focus and name to Biosystems Engineering.
Publications
Publications (49)
As a response to growing land and freshwater shortages and climate change, the use of seaweeds as food, their cultivation at sea and its effect on biodiversity are being researched on both the Caribbean and Pacific coasts of Costa Rica. Native species, more plentiful on the Caribbean coast, were collected and pre-selected based on existing informat...
Simple techniques to grow land crops (tomato, lettuce, bean, maize, etc) potted and floating on lakes are described. The advantage of implementing these production systems is that extensive aquatic areas can be used and no water is used because the same water that evaporates anyway from the lake surface is now transpired by crops. Results evidencin...
Seaweed farming at sea is proving an increasingly competitive biomass production alternative for food and related uses. Farmed seaweed output has been growing exponentially, reaching 24 million tons by 2012. Remarkably, 99 % of this production occurred in merely eight Asian nations. Most of the remaining 150 countries and territories with coasts ar...
To meet carbon emissions targets, more than
30 countries have committed to boosting production
of renewable resources from biological materials and
convert them into products such as food, animal feed
and bioenergy. In a post-fossil-fuel world, an increasing
proportion of chemicals, plastics, textiles, fuels and
electricity will have to come from b...
El documento contribuye al avance del uso sostenible de los recursos marino-costeros. En ese contexto se describe el proceso de selección de macroalgas nativas, su cultivo principalmente utilizando líneas flotantes y luego el uso de lo así producido como alimento humano. La última parte del documento comprende varias recetas utilizando macroalgas,...
Over the last two decades, the sequestration of carbon in soils has often been advocated as a solution to mitigate the steady increase in the concentration of CO2 in the atmosphere, one of the most commonly mentioned causes of climate change. A large body of literature, as well as sustained efforts to attract funding for the research on soil organi...
To complement dwindling fisheries, white shrimp (Litopenaeus vannamei) was cultured at small scale by men and women of six fishing communities in low-cost floating cages made by them at sea near-shore in the Gulf of Nicoya, Pacific coast of Costa Rica. Growth and farming data were collected for 19 separate production events, six of them including p...
Freshwater shortages are increasingly limiting both irrigated and rainfed agriculture. To expand possibilities for controlled plant production without using land nor freshwater, we cultivated potted halophytes floating at sea that were provided with rain- and seawater. Plantlets of two mangroves (Avicennia germinans and Rhizophora mangle) and plant...
By 2050, human demand for food will increase by 70 %, or 5.4 thousand million tonnes per year. However, agriculture’s capacity to provide it is constrained by lack of additional land and freshwater, and is threatened by climate change. In response, this chapter explains how and why more seaweeds should be farmed at sea to supplement production of p...
Radulovich, R. 2015. Foods from Aquaculture. Abstract
Aquatic food production, broadly known as aquaculture, is already strong and expanding fast the world over. The growing supply and variety of foods from both fresh- and salt-water aquaculture represent a timely gastronomic revolution, particularly considering that fisheries are dwindling. This c...
Cellulase produced from the marine fungus Cladosporium sphaerospermum through solid state fermentation
(SSF) was investigated for its saccharification potential of seaweed biomass using the common green seaweed
Ulva fasciata. The seaweed substrate, containing inoculated fungus with 60% moisture content, cultured at
25 °C and pH 4 for four days, sho...
Cropping on water surfaces using land crops or eventually developing the cultivation at any depth of aquatic plants as crops, showed to be a viable option that can be implemented sustainably. Perhaps most beneficially, by using only water that anyway evaporates from the surface of lakes and dams, massive amounts of freshwater can be made available...
Considerando esto, y las ventajas que ya existen como semilla de alta calidad a un costo competitivo, alimento formulado y, sobre todo, mucho conocimiento sobre los diferentes aspectos de la producción, desde hace años nosotros así como colegas en México, Brasil y Perú, hemos independientemente explorado como alternativa o complemento el crecimient...
Aquatic and sustainable food production systems directly applicable on lakes are described, emphasizing as case activities that can be implemented at Lake Malawi.
Water is becoming the most severe and widespread limitation to increasing world food production and security. While irrigation is a very limited option precisely due to lack of water, rai...
When the Soil Science Society of America was created, 75 yr ago, the USA was suffering from major dust storms, causing the loss of enormous amounts of topsoil as well as human lives. These catastrophic events reminded public officials that soils are essential to society's well-being. The Soil Conservation Service was founded and farmers were encour...
Water scarcity may be the most limiting factor to increasing world food production. Irrigation water is already overdrawn beyond sustainable levels and to increase reliance on rainfed agriculture is risky, even more so with climate change. However, to promote deliberate food production at sea, both fished and farmed, and both plant and animal, requ...
In research funded by the Development Marketplace Program of the World Bank, the author describes growing shrimp in floating cages located in the Gulf of Nicoya off Costa Rica. The shrimp farming could provide coastal populations with alternative sources of income while also reducing pressure on natural resources. Shrimp, a favored fishing and pond...
Growing demands on world agriculture confront increasing freshwater limitations. To contribute alternatives, we have explored with considerable success the growth of land plants at sea off the Pacific coast of Costa Rica, irrigated with freshwater produced in situ through rainwater harvesting and/or passive solar distillation. Two different approa...
Se presenta un procedimiento simple, acompañado de la descripción del cilindro muestreador, para determinar por peso el contenido volumétrico de agua del suelo (Avol), directamente en el campo. Avol se determina muestreando y pesando cilindros con volumen conocido de suelo sin disturbar, comparando ese peso con el de una muestra similar con Avol ya...
Seaweed could be cultivated large scale as a biofuel The environmental and social costs of producing biofuels on land can be avoided by farming seaweed, says Ricardo Radulovich. The dream of tackling climate change with biofuels has been tarnished by the rush to produce them on land. Not only are there serious environmental costs, including defores...
La existencia humana se fundamenta en una bioeconomía que nace de la fotosíntesis, incluso de la fotosíntesis de antaño que produjo el combustible fósil. La sistematización en la captura de energía solar y carbono del aire por medio de esa fotosíntesis y las subsecuentes cadenas tróficas, o sea la agricultura, se ha limitado históricamente a la tie...
Las conocidas y crecientes limitaciones a la agricultura, pesca y disponibilidad de agua para riego tienen pocas soluciones viables y muy probablemente se acrecentarán con el cambio climático. Para contrarrestar estos y otros problemas, estamos desarrollando con y para pobladores costeros empobrecidos, unos sistemas productivos flotantes altamente...
In the seasonal (wet-dry) tropics, yields of rainfed staple crops are usually low and variable. However, our simulations have indicated that rainfall could be used more efficiently, increasing the length of the rainfed cropping season, the number of crops grown, and their yields, while decreasing yield variability and risk. To evaluate these predic...
Se presenta la extensión agrícola desde la perspectiva de su aplicación a países de Latino América principalmente.
Agricultural extension is discussed from the perspective of its application to tropical developing country conditions, particularly Latin America.
Se realiza un análisis sobre el efecto de la deforestación y las inundaciones en función de las externalidades de los sistemas productivos agrícolas.
Laboratory method to investigate flow of water and fertilizers in undisturbed soils. The effects that the high degrees of structure and micro-structure of tropical soils can have on water flow and interaction with fertilizers have not been thoroughly studied, in spite of being possibly of great relevance on economic and environmental aspects. This...
The effects of irrigation and the rainy season on soil gases, water and physical properties were studied in a lowland moist forest in Panama. Two control plots experienced a normal four-month dry season and two experimental plots were irrigated during the dry season.
The forest soils were well aerated. The average soil oxygen content at 20 cm never...
Se presenta el tema de validación de tecnologías agrícolas en las manos de los agricultores mismos, como parte de un esfuerzo experimental necesario de previo a la extensión o diseminación de una innovación.
Bypass flow was measured in two microaggregated Inceptisols from the humid Atlantic region of Costa Rica under water-application rates below those needed to produce ponding. Water was applied with a constant-head rainfall simulator to undisturbed soil cores taken when soils were near field capacity. For each application rate, in contrast to classic...
Se analiza la dicotomía existente entre pequeños agricultores tradicionales y la producción agrícola más tecnificada y a mayor escala.
Indices of water deficit (IDef) and of deficit + excess (IStres) produced with the water balance model AQUA were correlated against rainfed regional yields of one annual planting of rice and beans, and of two different planting dates of maize. Data used are from northern Costa Rica, with 12 years of rice yield data available and eight years for the...
Tropical deforestation is frequently decried as a potential cause of future environmental disaster. But is this attitude fair? And does it take into account the reality of life in the developing countries?
A new method for characterizing macropore size distribution is presented for a well-aggregated Oxic Dystropept at La Selva, Costa Rica, known to exhibit macropore flow. Samples were taken as undisturbed cores from a secondary forest and an abandoned pasture. The method is based on hydraulic principles including the Poiseulle equation, and on water...
An approach to upgrading rainfed tropical cropping, based on the optimization of rainfall water use, is presented. As an example, two stations in Costa Rica, with a rainy season of six to eight months and a dry period in the rainy season (veranillo) were used. These stations represent a large portion of the Pacific coast of Central America.The pote...
Effects of soil structure on solute transport were studied in a clayey, well-aggregated Oxic Dystropept under grass and secondary forest at La Selva, Costa Rica. Field application of Rhodamine B dye without ponding (simulating heavy rainfall) showed preferential flow along decayed-root channels, animal burrows, cracks, and other macro-pores. Prefer...
A practical model that considers both deficits and excesses as days of stress, AQUA, was developed and validated against crop yields from Northwestern Costa Rica. AQUA is based on daily water balance calculations, and inputs are: Daily precipitation (P); averages of monthly potential evapotranspiration (ETP); and crop and growth stage parameters th...
Published collection efficiencies (volume of water collected divided by percolating volume calculated from a water balance) of zero-tension lysimeters are <10%, suggesting that samples collected by such lysimeters may not be representative of the water percolating downward. By increasing catchment area to 2500 cm 2 , and by pushing the lysimeter ri...
Rainfall prediction for the end of rainy season in the Pacific Regime. An inverse relationship was found between the monthly precipitation values of the begining of the rainy season and the values for the end of the rainy season of the same year, for six stations from the semidry Pacific Regime of Costa Rica. Early season (Mayor April + May) values...
Compaction of an alluvial soil of volcanic origin due to foot traffic. We studied some effects of walking on bare soil while removing the vegetation from an abandoned pasture with a machete at a humid lowland site in Costa Rica. The control treatment consisted of clearing plot vegetation from outside the plot without stepping on the soil. Walking o...
The Hydraulic Press (HP) is gaining some acceptance as a tool for estimating plant water status and some large cotton growers in the Central California area are already using this instrument for irrigation scheduling. Since no published data validating the use of the HP with cotton have been found, the objective of this research was to develop a da...
Questions
Questions (2)
Even though 'tropical seaweeds' is a very broad field, as it would be 'temperate seaweeds', I still would like to have the most useful guides at hand just to see not only if I ever get them right but it is important to systematize the guides for farming/harvesting from the wild to use them, separating this field from the more phycological one that needs to identify every seaweed.
Food production needs to be doubled by 2050, yet 90% of increases must come from increases in productivity (i.e. yield/area) while only 10% from increasing farmed land area. The reason is that there is growing shortage of adequate land area to be added into agriculture. This is very much related to growing shortages of freshwater--essential for agricultural production at the rate of ca. 50.000 liters/ha/day.
70% of the world's available water is already used for irrigation
Climate change is having negative impacts on agriculture.
The ocean has all the water and space that is needed, plus an overabundance of nutrients for fertilizer-free seaweed production up to a considerable scale.
Seaweeds have been amply shown to be very productive and edible/nutritious. (24 million tons were produced by farming in 2012).
What is stopping the development of this extremely valuable resource? Can it be that most people have not asked themselves the question? That's why I asked it from you. Thank you for sharing your thoughts and insights.
