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Long Term Experiments

Long-term experiments (LTEs) are robust research instruments for ecosystem productivity and sustainability because these capture the behavior and relationship between crop production systems and the changing environment at different time points over long periods.

Inspired by the Green Revolution, IRRI proactively begun looking at the sustainability of intensive rice cropping systems in the 1960s with the long-term vision of determining interactions between different ecosystem components.

The institute has been at the forefront of rice research using more advanced rice varieties, fertilizer management, irrigation approaches, and modern pest control methods. After almost 60 years, IRRI is still leading in what is now called sustainable agricultural intensification. 

In particular, IRRI’s long-term continuous cropping experiment (LTCCE) which has been running for more than 50 years has become one of a few ‘classical’ long-term experiments in the world. It is also the longest-running triple rice cropping experiment globally.

What we contribute

Information and insight from LTEs are valuable in addressing UN Sustainable Development Goals (SDGs) on Zero Hunger (SDG 2) and Life on Land (SDG 15), among others.

IRRI’s LTE continues to provide evidence on how agronomic management and improved rice varieties contribute to higher system productivity and resource use efficiency while minimizing environmental impacts under changing climates.

The massive compendium of IRRI LTE data from the 1960s to the present is a valuable asset. It documents yield trends over time and reflects how the changing climate has affected the performance of intensive rice cropping systems.

Dedicated to its mission of ensuring the sustainability of rice-based agroecosystems, IRRI maintains the operation and management of the IRRI LTE at a minimum cost. In 2017, the Deputy Director General for Research (DDGR) initiated launching the long-term experiments at the HQ as a common resource for all IRRI researchers.

Data access policy is now in place and these long-term datasets are open to IRRI researchers for reuse in addressing current sustainability questions. IRRI researchers, using their respective resources, are welcome to gather measurements and observations in these long-term experiments (including remote sensing and ground-truthing).

IRRI’s existing Soil Archive (est. 1983) also offers a rare resource that allows scientists to step back in time to investigate sustainability indicators using more advanced methodologies that are now available.

Outputs and Deliverables

  1. Research on sustainability of rice-based ecosystems using long-term experiments
  2. FAIR (findable, accessible, interoperable and reusable) data management and collection for addressing sustainability research questions through local and international collaborations
  3. Publications
  4. Capacity building