AN ON-LINE KNOWLEDGE CENTER FOR WATER AND NUTRIENT MANAGEMENT FOR THE NURSERY AND GREENHOUSE INDUSTRY

We have developed a web-based knowledge center for water and nutrient management and conservation, for the nursery and greenhouse industries. Increasing environmental concerns and legislation in the Unites States and other countries require that we take a more comprehensive approach to improving and integrating cultural best management practices, since these operations are typically intensive users of resources which are applied to relatively small land areas. The website (http://www.waternut.org) provides the general public with an overview of the project and a link to the knowledge center (http://www.waternut.org/moodle/), which provides access to more than twenty intensive learning modules over the internet, within a Moodle learning management framework. These learning modules have been designed to actively engage learners in topics on substrate, irrigation, surface water, nutrient and pathogen management, which are integral to formulating farm-specific strategies for effective water and nutrient management. Additionally, tools such as irrigation audits and water and nutrient management planning are covered in specific modules. Over fifty regulatory agency, industry and education professionals have been active in the developmental review of these resources, through face-to-face workshops and on-line reviews of content. By providing on-line access to in-depth learning modules though this knowledge center, we intend to reach out to many different audiences, to a comprehensive informational resource of best management practices, to increase the efficiency of 693 Proc. IS on Greensys2007 Eds.:S. De Pascale et al. Acta Hort. 801, ISHS 2008 resources used by commercial ornamental operations. BACKGROUND The ornamental (nursery and greenhouse) industry is a major economic force in US agriculture, which in 2002 had 4.82M acres in production, accounting for 15.4% of wholesale crop receipts, with an average net return of $947 per acre (USDA, 2002). This industry is highly diverse in terms of production practices and the species of plants grown, with approximately 400 genera and more than 2000 species of ornamentals in production. Container-nursery and greenhouse systems differ radically from traditional agronomic-type agricultural operations in terms of how they use water and nutrients. This is because these industries produce plants in soilless substrates which differ markedly in how they retain water and nutrients in comparison to traditional soils. There is no doubt that we need to take more effective steps to manage and conserve resources, in general. In order to do this, we need to effectively coordinate our existing educational resources, to increase the knowledge and capacity of the diverse group of professionals that serve these industries, and identify the gaps in our knowledge that require further research. The majority of ornamental plant material grown in the United States is produced in container-nursery or greenhouse operations. These operations are classified as intensive agricultural systems because they use a combination of expensive resources (labor, water, fertilizers, etc.) to produce plants in large numbers on small acreages. Water and nutrient management is complicated for these operations, for a number of reasons (Lea-Cox and Ross, 2001), including the fact that the nutrient efficiency of many species has not been adequately researched, especially for herbaceous and woody perennial species; the growth rate and hence the nutrient uptake of many species varies specifically with temperature, together with other environmental growth factors, especially water; nursery and greenhouse systems use a wide range of irrigation methods to grow different sizes of plants and species demanded by the marketplace; the nutritional requirements of this wide range of species means that producers rely on a variety of fertilization methods, including conventional, controlled-release, and soluble fertilizers, where appropriate; production times for annual species can range from weeks to month, whereas production times are typically from a few months (for herbaceous species) to years for woody perennials and large trees. Also, semi-closed or closed production systems require an advanced knowledge of plant health and pathogen management, which is often a deterrent to recycling water and nutrients. The quantity and quality of water used by intensive agriculture are topics of national interest since clean water is a critical requirement to sustain natural and managed terrestrial and aquatic ecosystems. Non-point source (NPS) nutrient pollution is a leading cause of degraded water quality in the United States. Water and nutrient management have consistently ranked within the top five research priorities of grower organizations in the United States during the past decade (American Nursery and Landscape Association, 2004). Increasing public demands on water supplies and water treatment, the possibility of high nutrient (nitrogen and phosphorus) discharge rates to rivers and groundwater, and increasing legislative and regulatory requirements are all factors driving the need for efficient management of resources, to mitigate impacts on the environment. As agricultural and urban development intensifies over time, the ability of watersheds to process nutrients will be much more uncertain. Land-use change has been identified as the most significant local, regional, and global human impact on the hydrologic system (Bhaduri et al., 2000). Given the nationwide expansion of ornamental production and the intensive use of water and nutrients by these operations, we have to ensure that producers are familiar with the most current best management practices.