Ecological Intensification & Perennial Polyculture
Ecological intensification aims to harness ecological processes in order to keep pests in check, maintain fertility and prevent loss of soil, nutrients, and organic matter.
Our researchers believe that perennial polycultures offer previously unattainable levels of ecological intensification in agriculture. This contrasts with the advent of chemical-based input intensification that was responsible for increased yields in industrial agriculture last century.
Why Ecological Intensification?
- Plant diversity is important because it helps to keep populations of plant-loving insects and diseases in check.
- Diversity also tends to enhance productivity because resources such as sunlight, water, and nutrients are used more efficiently when species with different resource requirements grow together.
- Perenniality is important because when vegetation lives for many years, soils are not only protected against erosion, but they actually build and accumulate organic matter.
- Deep-rooted perennial plants are able to access nutrients and water that escape the reach of annual plants.
- With the intercrop systems, called polycultures, The Land Institute hopes to incorporate the benefits of diversity seen in nature.
- Ecological Intensification harnesses ecological processes to supplant the need for commercial inputs like fertilizers and pesticides.
- Researchers believe that by combining perennality and diversity in grain agriculture, levels of ecological intensification that were previously unachievable will effectively address many problems inherent in annual agriculture—including severe pest outbreaks, soil erosion, nutrient leakage and soil organic matter loss.
Levels of Ecological Intensification
At The Land Institute, we focus on everything from individual crop attributes, to how organisms interact with other organisms as well the soil and atmosphere in order to maximize what the ecosystem can be achieved through ecological intensification.
We’re working on three levels of ecological intensification to transform agriculture from having a degenerative to a regenerative impact:
All species in natural ecosystems have undergone many cycles of natural selection resulting in adaptations to specific ecological conditions. For example, many grass species have developed resistance to specific plant diseases. Genes coding for disease resistance can be incorporated into perennial crops through breeding. Perennialism is another trait that occurs at the species level and is controlled by numerous genes.
Plant communities in wild ecosystems usually feature many species. Biodiversity in plant communities helps to reduce disease and insect damage throughout the system, and helps plants take advantage of resources such as water, nutrients, and sunlight. Multi-species communities will help ensure more stable ecosystems for perennial grain agriculture.
It is extremely rare for wild ecosystems to remain in a disturbed state for very long. After disturbances like fire, drought, or floods, perennial species either re-sprout or germinate and take over dominance from ephemeral annual plants. Below ground, the quality of soil organic matter changes during succession as does the community of microorganisms that it supports.
What Is Succession and Why Does it Matter?
Ecological succession is a process of change that occurs after forests, grasslands, or other types of ecosystems have been disturbed by natural forces such as fire, floods, or drought. If disturbances are intense, ecosystems can be set back to very early stages of succession, often characterized by the proliferation of annual plant species, losses of nutrients, soil organic matter, and even topsoil itself.
In the wild, periods of high disturbance are almost always brief. No sooner does the ecosystem get knocked back with a disturbance such as a very hot fire, than perennial plants begin to sprout, soil organic matter begins to rebuild, soil microbes change, and the functioning of the ecosystem begins to improve.
In modern annual agriculture, we hold the ecosystem in the highly disturbed and highly compromised state indefinitely. By arresting succession, we make “permanent” a poorly functioning ecosystem that is extremely transient in natural ecosystems.
Perennial crops, which put far more energy into roots below ground and do not require frequent disturbance, allow for succession to take place once again. At The Land Institute, we are learning about the role succession plays in governing ecosystem functions in newly developed perennial polycultures.
Ecological Instensification Programs
At The Land Institute, we are working to combine plantings of complimentary perennial species in “intercrops” or “polycultures” and examine the critical functions of natural systems into agriculture: nutrient retention, carbon sequestration, and soil regeneration, and other indicators of soil health.
Additionally, The Ecology Team is learning how we can use crop diversity paired with biological control agents to manage pests and pathogens in our perennial crop systems.
Crop Protection Ecology
The Crop Protection Ecology team is learning how we can use crop diversity paired with biological control agents to manage pests in our perennial crop systems to create the kind of agricultural habitat that will make these grains as sustainably pest-free and productive as possible.
Crop Protection Genetics
Our Crop Protection Genetics Team is seeking to understand and control the diseases in our perennial crops by identifying potential pathogens, developing methods for monitoring their infection rates and measuring their damage, and determining which are most problematic.
Soil and Intercrop Ecology
The Soil and Intercrop Ecology program examines the critical functions of natural systems into agriculture: nutrient retention, carbon sequestration, and soil regeneration, and other indicators of soil health.
Additionally, The Land Institute is working to combine plantings of complimentary perennial species in “intercrops”. We are currently exploring Kernza and alfalfa bicultures and evaluating the biological nitrogen fixation of this intercrop. Other grain-legume combinations are also being considered.
Join us by supporting this work with a donation to The Land Institute.
Director of Ecological Intensification/Lead Scientist, Soil Ecology Program
Lead Scientist, Crop Protection Ecology
Research Associate, Crop Protection Genetics
Post Doctoral Research Associate, Crop Protection Ecology
Research Technician, Crop Protection Ecology
Research Technician, Ecology
Eric A. Cassetta
Soil Ecology Technician
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