Increased crop diversity enhances soil food web structure and ecosystem function

Contributed by: Tvisha Martin

 

Keywords

Agriculture, Agroecosystem, Biodiversity, Biogeochemistry: C, Biogeochemistry: N, BIPOC, Climate change, Competition, Conservation, Consumption, Ecology, Environmental change, Field, Fundamental research, Person of color, Indian, Interactions, Lab, Nematode, North America, Terrestrial, Woman

 

Slides

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View and download in google slides here

 

Resources

Martin, Tvisha, and Christine D. Sprunger. Soil food web structure and function in annual row-crop systems: How can nematode communities infer soil health? Applied Soil Ecology 178 (2022): 104533 link

 

Notes

Slide 1: Researcher’s Background

Tvisha Martin is a soil scientist at Michigan State University where she studies how nematodes can be used as soil health indicators in agricultural systems.

PB: Why did you become a biologist?
TM: I became a biologist because I was exposed to the issues that losses in biodiversity such as agricultural intensification can cause to the environment. When I was young my city’s water supply was contaminated leaving us without water for 3 days. I quickly learned that intensive agriculture degraded the soil biodiversity so much that all fertilizer was running off into Lake Erie. This experience prompted my love for soil biodiversity preservation.

PB: What is your favorite part about your job?
TM: My favorite part of the job is getting to be outside and enjoy nature while sampling for my research.

PB: What obstacles have you overcome to get where you are?

TM: I have had to overcome a large race barrier to get where I am. My field is predominantly male and white – it has taken a lot of courage and standing up for myself to be a doctoral student in this field. In addition, I have had to battle the common perception from many of my Indian family members so they understand that being an agricultural scientist is a field that I have to also work very hard in, just like in medicine, engineering, or business.

PB: What advice do you have for aspiring biologists?
TM: I advise aspiring biologists to be curious and question everything they see in our natural world. You never know where your curiosity will take you and what doors it may open for you in terms of scientific discovery.

PB: Do you feel that any dimension of your identity is invisible or under-represented/marginalized in STEM?
TM: Yes

PB: Can you elaborate on your answer above?
TM: My race of being a POC woman is underrepresented in the Agricultural Sciences field.

 

Slide 2: Research Overview

Take home message of study

Increased agricultural management intensity is known to degrade soil food web structure. Nematodes play a large role in soil food webs and can be studied as indicators of food web structure. There are many types of nematodes found in soil and they are broken down into feeding groups based on their diet. Tvisha found that the types and diversity of nematodes found in the soil of agricultural systems differ based on the diversity of crops that have been planted in the field and whether the land was in a till or no-till rotation. These differences are important because increased food web structure can lead to improved ecosystem functioning. She found that overall, agriculture systems with greater crop diversity can enhance soil food web structure and therefore has the potential to improve carbon and nitrogen cycling.

 

Study system

A picture of a nematode (left) and the agricultural study site that Tvisha worked in (right).

 

Slide 3: Key Research Points

Key figure

Tvisha collected data on the types and diversity of nematodes in the soil for four types of agricultural systems – corn-soy with till, corn-soy no-till, corn-forage-forage chisel, and corn-forage-forage no-till. The nematode communities in each of these systems are depicted in each graph with different colored circles. 

The direction of each arrow points to what nematode community the soil health indicator is associated with. A red arrow indicates a significant association. 

This figure shows that indicators representing nitrogen (NAG, Protein) and carbon (GLU, POXC) in soil are positively related to systems with greater crop diversity (Corn-Forage-Forage till, and Corn-Forage-Forage No-till). 

 

Societal Relevance

This paper is important because it indicates that sustainable management practices (Corn-soy no-till, corn-forage-forage till, corn-forage-forage no-till) can enhance soil biological health and therefore may have important implications for nutrient cycling and enhances soil health.