Katherine L. Gross, Director and University Distinguished Professor W.K. Kellogg Biological Station and Department of Plant Biology

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1 Ecosystem Services and Diversity in Agricultural Systems Katherine L. Gross, Director and University Distinguished Professor W.K. Kellogg Biological Station and Department of Plant Biology Michigan State t University it kgross@kbs.msu.edu

2 What are ecosystem services? Ecological systems have the potential to provide a diversity of services that enhance and sustain human well being The value of these services has been estimated to be in the Trillions of Dollar$$ Constanza et al 1997 Diverse ecological communities have the capacity to provide us with a greater variety of ecosystem services

3 Agricultural and Ecosystem Services Food, fiber and fuel are important ecosystem services provided by agricultural systems Conventional agricultural Conventional agricultural practices have focused on increased crop production.. an increase in one ecosystem service

4 Corn Production and Inputs These on farm increases in yields are driven by increased inputs fertilizer, pesticides and technologies (GMOs) Hatfield& Pruger 2004;

5 Unintended Offsite consequences Nutrient inputs to Mississippi River have increased with fertilizer use in the Midwestern US

6 An offsite cost: Coastal Dead zones Increased nutrients to coastal areas, attributed to agricultural practices, create dead zones, which devastate coastal fisheries A off site loss of ecosystem services can can cost millions of dollars Goolsby, D. and W. Battaglin, 1997.

7 N retention and removal by Wetlands Wetlands and vegetated zones adjacent to agricultural lands can reduce downstream N inputs Habitats can be created to increase the landscape capacity to intercept and remove Nitrogen from ground water

8 Pollinator Services for Agriculture World wide pollination services to crop plants are estimated $10B in US Native pollinators have been reduced due to habitat loss, disease and pesticides Reductions in commercial honey bee populations are increasing costs of providing this service Pollinator Services: Almonds 2000 $40/hive 2004 $75/hive 2006 $140/hive 2007 $200+/hive (estimated) NRC 2006

9 Native bees from adjacent habitats enhance crop yield Recent work in CA has shown that pollination by native bees enhances fruit set in commercially important crops Chapparal habitats near agricultural fields are the habitat (source) for native bees Adjacency of wild habitat to agricultural fields increases this service Greenleaf & Kremen PNAS 2006

10 Soybean aphid Damage Biological Control: Soybean Aphid Soybean aphids first detected in 2000, now occur in 21 states Can cause 40-50% yield loss Estimated cost to control with pesticide: >$90M Experimental work at KBS has explored potential for Biological Control

11 KBS-LTER Experimental Design TREATMENTS: S P A Early successional Poplars Alfalfa P5 C1 A5 N5 L5 C5 S5 O5 N2 N3 L4 C Conventional tillage S1 L2 O3 N4 N No till P1 O2 S3 C4 L Low input / legume cover P6 A6 N6 L1 P2 A3 O4 O Organic / Legume cover S6 O6 O1 C2 L3 A4 L6 C6 100 m N1 A2 P3 S4 A1 S2 C3 P4

12 Field inputs affect pests and predators Densities of aphids are lower in organic treatments Predators, lady beetles, keep aphid density below critical thresholds h Evidence for within field or on farm ecosystem services Costamagna & Landis 2007 Ecol Appl

13 Off Farm Habitats Sustain Predators Woods and uncultivated habitats adjacent to croplands are critical to sustaining predator services (Ladybeetles ) to crops Overwintering Aggregation sites Feeding Reproduction Uncultivated habitats Cultivated habitats Colunga & Gage 1998

14 Strong Biocontrol potential if system managed for biodiversity (ecosystem service) Top-down 3 7 x Generalist predators Soybean aphid Bottom-up x Soybean plant Costamagna & Landis 2007 Ecol. Appl.

15 How can we enhance diversity in agricultural landscapes?

16 On Farm Change inputs Organic Cover crops On and Off-farm farm approaches Off farm Managing the landscape Cropped and uncropped lands

17 Conclusions 1. Strong potential for enhancing ecosystem services in agriculture by changing practices on and off-farmfarm Reduced inputs, cover crops and rotations can increase internal benefits: nutrient management, pest control On-farm management can reduce or enhance potential lf for ecosystem services from surrounding habitats 2. Need to consider off-farm farm (landscape scale) potentials for ecosystem services Proximity to unmanaged areas can influence ecosystems services provided to - and lost from- agricultural landscapes Active management of off-farm farm landscapes can enhance ecosystem services on farm