Lisa A. Schulte

Homogenization of northern U.S. Great Lakes forests due to land use

Human land use of forested regions has intensified worldwide in recent decades, threatening long-term sustainability. Primary effects include conversion of land cover or reversion to an earlier stage of successional development. Both types of change can have cascading effects through ecosystems; however, the long-term effects where forests are allowed to regrow are poorly understood. We quantify the regional-scale consequences of a century of Euro-American land use in the northern U.S. Great Lakes region using a combination of historical Public Land Survey records and current forest inventory and land cover data. Our analysis shows a distinct and rapid trajectory of vegetation change toward historically unprecedented and simplified conditions. In addition to overall loss of forestland, current forests are marked by lower species diversity, functional diversity, and structural complexity compared to pre-Euro-American forests. Today’s forest is marked by dominance of broadleaf deciduous species—all 55 ecoregions that comprise the region exhibit a lower relative dominance of conifers in comparison to the pre-Euro-American period. Aspen (Populus grandidentata and P. tremuloides) and maple (Acer saccharum and A. rubrum) species comprise the primary deciduous species that have replaced conifers. These changes reflect the cumulative effects of local forest alterations over the region and they affect future ecosystem conditions as well as the ecosystem services they provide.

Ecological effects of large fires on US landscapes: benefit or catastrophe?

The perception is that todays large fires are an ecological catastrophe because they burn vast areas with high intensities and severities. However, little is known of the ecological impacts of large fires on both historical and contemporary landscapes. The present paper presents a review of the current knowledge of the effects of large fires in the United States by important ecosystems written by regional experts. The ecosystems are (1) ponderosa pine-Douglas-fir, (2) sagebrush-grasslands, (3) pinon-juniper, (4) chaparral, (5) mixed-conifer, and (6) spruce-fir. This review found that large fires were common on most historical western US landscapes and they will continue to be common today with exceptions. Sagebrush ecosystems are currently experiencing larger, more severe, and more frequent large fires compared to historical conditions due to exotic cheatgrass invasions. Historical large fires in south-west ponderosa pine forest created a mixed severity mosaic dominated by non-lethal surface fires while todays large fires are mostly high severity crown fires. While large fires play an important role in landscape ecology for most regions, their importance is much less in the dry pinon-juniper forests and sagebrush-grasslands. Fire management must address the role of large fires in maintaining the health of many US fire-dominated ecosystems.

Targeting perennial vegetation in agricultural landscapes for enhancing ecosystem services

Over the past century, agricultural landscapes worldwide have increasingly been managed for the primary purpose of producing food, while other diverse ecosystem services potentially available from these landscapes have often been undervalued and diminished. The incorporation of relatively small amounts of perennial vegetation in strategic locations within agricultural landscapes dominated by annual crops—or perennialization—creates an opportunity for enhancing the provision of a wide range of goods and services to society, such as water purification, hydrologic regulation, pollination services, control of pest and pathogen populations, diverse food and fuel products, and greater resilience to climate change and extreme disturbances, while at the same time improving the sustainability of food production. This paper synthesizesthe current scientific theoryand evidence for the role of perennial plants in balancing conservation with agricultural production, focusing on the Midwestern USA as a model system, while also drawing comparisons with other climatically diverse regions of the world. Particular emphasis is given to identifying promising opportunities for advancement and critical gaps in our knowledge related to purposefully integrating perennial vegetation into agroecosystems as a management tool for maximizing multiple benefits to society.

High crop prices and conservation Raising the Stakes

Agricultural conservation policy does not happen in a vacuum but, rather, is linked to a myriad of other policies affecting individual farms, national and international trade, and energy production and distribution. While the primary purpose of commodity subsidies is to supplement farmer income, they have also had a strong influence on cropland expansion and agricultural intensification. One result of this expansion and intensification has been burgeoning crop productivity. Another has been a decline in the provision of ecosystem services, the benefits that people obtain from ecosystems. The services people obtain from agroecosystems include soil stabilization and enhancement, water filtration and flood control, carbon sequestration, wildlife habitat, and recreation opportunities (e.g., hunting and wildlife viewing). This tension between farmer income support and the provision of ecosystem services is inherent to the current configuration of US agricultural conservation policies such as the Conservation Reserve Program (CRP). Developed during a time of crop surpluses, CRP was originally a set-aside mechanism to reduce both soil erosion and the overall amount of crops produced. Today, the program has a stronger focus on environmental impacts. The recent emergence of the bioeconomy—which we define as the production, distribution, and consumption of agricultural goods and services to meet

Bird Communities of Early-Successional Burned and Logged Forest

Because logging has replaced fire as the most extensive and frequent disturbance regime in northeastern Minnesota, monitoring bird populations and their habitats has become increasingly important. We surveyed early-successional forests created by fire or logging for birds and their habitat during the 1994 and 1995 breeding seasons. We found that overall bird species richness and number of individuals (territorial males/ ha) were higher (P < 0.05) in burned forests than in logged forests. The American crow (Corvus brachyrhynchos), house wren (Troglodytes aedon), common yellowthroat (Geothlypis trichas), clay-colored sparrov (Spizella pallida), song sparrow (Melospiza melodia), Lincolns sparrow (M. lincolnii), and brown-headed cowbird (Molothrus ater) were more abundant in burned areas. The Nashville warbler (Vermivora ruficapilla), chestnut-sided warbler (Dendroica pensylvanica), black-throated green warbler (D virens), and mourning warbler (Oporornis agilis) were present in greater numbers in the logged areas. We related these differences in bird presence and abundance to vegetation differences in the burned and logged habitat types. Burned areas had higher densities of dead trees, wider size ranges of dead trees, and greater heterogeneity in the shrub layer. Logged areas had higher densities of live trees, more live tree species, and wider size ranges of live trees. Red maple (Acer rubrum) was the live tree species found in greatest abundance in logged areas. If management goals include simulating natural disturbances like fire and maintaining bird populations, more dead trees should be left within logged habitats and the variability among logged areas should be increased.

Linking Resilience Theory and Diffusion of Innovations Theory to Understand the Potential for Perennials in the U.S. Corn Belt

In the last 200 yr, more than 80% of the land in the U.S. Corn Belt agro-ecosystem has been converted from natural perennial vegetation to intensive agricultural production of row crops. Despite research showing how re-integration of perennial vegetation, e.g., cover crops, pasture, riparian buffers, and restored wetlands, at strategic landscape positions can bolster declining regional ecosystem functions, the amount of land area devoted to row crop production in the Corn Belt continues to increase. As this region enters a time of fast-paced and uncertain reorganization driven by the emerging bioeconomy, changes in land use will continue to take place that will impact the resilience of the Corn Belts linked social and ecological systems for years to come. Both resilience theory and the diffusion of innovations theory investigate how change is brought about in systems through the adaptation and innovation of social actors. In this paper, we integrate these two frameworks in the analysis of 33 in-depth interviews to improve our understanding of how rural Corn Belt stakeholders make conservation decisions in the midst of an uncertain future. Interview data indicate that the adoption of conservation practices is based not only on immediate profitability but also on the interplay between contextual factors at three distinct levels of the system: compatibility with farm priorities, profitability, practices, and technologies; community-level reinforcement through local social networks, norms, and support structures; and consistent, straightforward, flexible, and well-targeted incentives and regulations issuing from regional institutions. Interviewees suggest that the multiscale drivers that currently support the continued expansion of row crop production could be realigned with conservation objectives in landscapes of the future. Adaptation of social actors through collaborative learning at the community level may be instrumental in brokering the sort of multiscale system change that would lead to more widespread adoption of perennial cover types in the Corn Belt.

Using biodiversity to link agricultural productivity with environmental quality: Results from three field experiments in Iowa

Agriculture in the US Corn Belt is under increasing pressure to produce greater quantities of food, feed and fuel, while better protecting environmental quality. Key environmental problems in this region include water contamination by nutrients and herbicides emitted from cropland, a lack of non-agricultural habitat to support diverse communities of native plants and animals, and a high level of dependence on petrochemical energy in the dominant cropping systems. In addition, projected changes in climate for this region, which include increases in the proportion of precipitation coming from extreme events could make soil and water conservation in existing cropping systems more difficult. To address these challenges we have conducted three cropping systems projects in central Iowa: the Marsden Farm Cropping Systems experiment, the Science-based Trials of Row-crops Integrated with Prairies (STRIPs) experiment, and the Comparison of Biofuel Systems (COBS) experiment. Results from these experiments indicate that (1) diversification of the dominant corn–soybean rotation with small grains and forage legumes can permit substantial reductions in agrichemical and fossil hydrocarbon use without compromising yields or profitability; (2) conversion of small amounts of cropland to prairie buffer strips can provide disproportionately large improvements in soil and water conservation, nutrient retention, and densities of native plants and birds; and (3) native perennial species can generate large amounts of biofuel feedstocks and offer environmental benefits relative to corn- and soybean-based systems, including greater carbon inputs to soil and large reductions in nitrogen emissions to drainage water. Increasing biodiversity through the strategic integration of perennial plant species can be a viable strategy for reducing reliance on purchased inputs and for increasing agroecosystem health and resilience in the US Corn Belt.

Landscape, community, countryside: linking biophysical and social scales in US Corn Belt agricultural landscapes

Understanding the interplay between ecological and social factors across multiple scales is integral to landscape change initiatives in productive agricultural regions such as the rural US Corn Belt. We investigated the cultural context surrounding the use of perennial cover types—such as stream buffers, wetlands, cellulosic bioenergy stocks, and diverse cropping rotations—to restore water quality, biodiversity, and ecosystem function within a Corn Belt agricultural mosaic in Iowa, USA. Through ethnographic techniques and 33 in-depth interviews, we examined what was most important to rural stakeholders about their countryside. We then used photo elicitation to probe how interviewees’ assessments of farm practices involving perennial cover types were related to their sense of place. Our interviewees perceived their rural “countryside” as a linked social and biophysical entity, identifying strongly with the farming lifestyle and with networks of people across the landscape. While most interviewees approved of perennial farm practices on marginal agricultural land, implementation of these practices was neither a priority nor strongly assimilated into rural experience and ethics. We identified three scale boundaries in our interviewees’ perception of place which present key challenges and opportunities for landscape change: landscape-community, individual-community, and community-institution. In all cases, community social norms and networks—exhibited at landscape spatial scales—may be instrumental in bridging these boundaries and enabling networks of perennial cover types that span privately owned and operated farms.

Oak Conservation and Restoration on Private Forestlands: Negotiating a Social-Ecological Landscape

In the midwestern United States, oak (Quercus spp.) forests are considered critical habitat for conserving biodiversity and are a declining resource. Ecological conditions, such as deer herbivory and competition from more mesic broad-leaved deciduous species, have been linked to poor oak regeneration. In the Midwest, where up to 90% of forestland is privately owned, a greater understanding of social dimensions of oak regeneration success is especially critical to designing effective restoration strategies. We sought to determine factors that serve as direct and indirect constraints to oak restoration and identify policy mechanisms that could improve the likelihood for restoration success. We conducted in-depth qualitative interviews with 32 natural resource professionals working in the Midwest Driftless Area. We found that most professionals anticipate that oak will remain only a component of the future forest. Furthermore, they identified the general unwillingness of landowners to adopt oak restoration practices as a primary driving force of regional forest change. The professionals pointed to interdependent ecological and social factors, occurring at various scales (e.g., economic cost of management, deer herbivory, and exurban residential development) as influencing landowner oak restoration decisions. Professionals emphasized the importance of government cost-share programs and long-term personal relationships to securing landowner acceptance of oak restoration practices. However, given finite societal resources, ecologically- and socially-targeted approaches were viewed as potential ways to optimize regional success.

Ecological and economic benefits of cross-boundary coordination among private forest landowners

A significant challenge facing forestry today is managing private forests sustainably in the face of continued ownership fragmentation (i.e., parcelization). Cross-boundary coordination––where forest practices are coordinated across multiple properties––has been proposed as a mechanism by which landscape-level ecological and economic benefits may be accrued in privately-owned landscapes, but few tests of the concept exist. Using a case study approach, we quantify the extent to which ownership-centric forest management is constrained by economies of scale and misses opportunities to achieve ecological objectives in three landscapes in Wisconsin, USA. Methods are based on existing forest management plans and include spatial analysis of patch distributions and shapes, simulation of forest practices, and calculation of net present value over a 20-year horizon. Our results indicate substantial opportunity for cross-boundary coordination: between 62% and 88% of the managed properties within our study landscapes were adjacent to other properties with forest management plans. At a patch scale, coordination can result in ecological benefits that can be accrued into the future (e.g., maintenance of large patches and natural ecosystem boundaries). Because these landscapes are already highly parcelized, however, coordination offers little opportunity to impact the overall landscape-scale structure. Greater economies of scale can also be gained by coordinating forest practices, including increases in the size (16–99%) and volume of timber sales (16–94%), and a modest economic advantage (3–6%). As first steps, investment in data infrastructure and professional training are required to support cross-boundary multi-ownership forest management. More broadly is the need to shift from policies and practices that are largely ownership-centric to those that include and better incorporate landscape-centric perspectives.