Farming in Canada and the USA is dominated by row cropping concentrated in central regions. Using the Corn Belt of Iowa and the Lake Erie Lowlands of Ontario—sources of pollution affecting the Gulf of Mexico and Great Lakes—as exemplary regions, this paper provides a retrospective review of the landscape effects of policies and practices related to environmental stewardship and agricultural trade. Conservation policies and typical farm practices are described and compared for the two regions with an emphasis on lasting beneficial environmental outcomes. Connections among land cover changes, environmental consequences, and changes in environmental and trade policies and programs are considered along with future changes in farm management, trade liberalisation, and farm revenue sources. The paper concludes with prospective ideas of how policies and practices can maintain or enhance environmental benefits within intensively farmed landscapes as best approaches for agriculture.
ABSTRACT: Appearances matter for managing riparian landscapes because the appearance of landscapes affects public willingness to accept plans and designs that improve ecological quality. Riparian landscape design and planning should respect and strategically incorporate characteristics that the public values and expects to see. Such design can be quite novel in its ecological effects, but it also should be sufficiently familiar in appearance to correspond with cultural values. This paper describes some influential cultural values for riparian landscapes and demonstrates how attention to such values supports public acceptance of ecologically innovative design in rural and urban watersheds.
Farm production practices often focus on mitigating negative consequences of cropping – particularly annual crops like corn, cereals and oilseeds. Some of North America’s most-intensive farmlands are rapidly converting their remaining perennial cover to annual crops. While perennial cover like woodlands, grasslands and wetlands are valued for the many landscape services they provide, they are vulnerable to conversion to other cover types under drivers of landscape change. Conversions within farms constitute nuances rather than new land uses, yet landscape composition effects can be substantial when considering habitat, biodiversity, soil and water quality, carbon sequestration, and aesthetics. As the farm landscape becomes increasingly dominated by annual crop vegetation, the key drivers behind land cover types and management merit critical examination. This paper reviews recent studies on farmland composition and management in central Canada and the United States, identifying trajectories and magnitudes of landscape changes. To consider forces, both speculative examination of policies and information from farmer interviews help identify motivations for changes in perennial or annual proportions of farm landscapes. The paper concludes with forces that increase perennialization and existing or prospective pathways to improve the balance between annual and perennial vegetation.
More than 80% of the people in the USA and Canada live in cities. Urban development replaces natural environments with built environments resulting in limited access to outdoor environments which are critical to human health and well-being. In addition, many urban open spaces are unused because of poor design. This paper describes case studies where traditional landscape architectural design approaches would have compromised design success, while evidence-based landscape architecture (EBLA) resulted in a successful product. Examples range from school-yard design that provides safe levels of solar radiation for children, to neighborhood parks and sidewalks that encourage people to walk and enjoy nearby nature. Common characteristics for integrating EBLA into private, public, and academic landscape architecture practice are outlined along with a discussion of some of the opportunities and barriers to implementation.
Landscape composition is consequential to ecological functions, and in agricultural regions a simple descriptor of composition is whether the growing habit of vegetation is annual or perennial. Annual vegetation includes most of the crop species grown in central North America (e.g., corn, soybeans, cereal grains, canola), and perennial vegetation includes hay and forage crops (e.g., alfalfa) and most non‐crop land covers (e.g., woodlands, grasslands, wetlands). Recent data show that in farmlands perennial cover is converting to annual cover. Using new remotely sensed annual crop layer spatial data for an intensively farmed region (1,700 km 2 ) of the Lake Huron watershed in Southern Ontario, Canada, this paper describes changes in farmland composition and which transitions are occurring, with suggestions for why the changes are occurring. Perennial cover has rapidly been converted to annual cover in the past five years, with working‐lands perennial cover types identified as the most vulnerable to conversion. Other land cover types are relatively static. Implications for agricultural land conservation and stewardship require attention to this rapid change for conservation of soil, water, and biodiversity in the Great Lakes basin.
Abstract Geomorphic river design strives for natural resilience by encouraging geomorphic form complexity and morphological processes linked to greater habitat diversity. Increasing availability of high‐resolution topographic data and spatial feature mapping methods provide advantages for morphological analysis and river restoration planning. We propose and evaluate an approach to quantifying topographic variability of geomorphic form and pixel‐level surface roughness resulting from channel planform geometry differences using spatially continuous variety computation applied to component metrics including flow direction, aspect and planform curvature. We define this as the geomorphic form variation (GFV) approach and found it scalable, repeatable and a multi‐stage analytical metric for quantifying physical aspects of river‐bed topographic variability. GFV may complement process‐based morphological feature mapping applications, hydraulic assessment indices and spatial habitat heterogeneity metrics commonly used for ecological quality evaluation and river restoration. The GFV was tested on controlled synthetic channels derived from River Builder software and quasi‐controlled sinuous planform flume experiment channels. Component variety metrics respond independently to specific geometric surface changes and are sensitive to multi‐scaled morphology change, including coarser‐grained sediment distributions of pixel‐level surface roughness. GFV showed systematic patterns of change related to the effects of channel geometry, vertical bed feature (pool‐bar) frequency and amplitude, and bar size, shape and orientation. Hotspot analysis found that bar margins were major components of topographic complexity, whereas grain‐scale variety class maps further supported the multi‐stage analytical capability and scalability of the GFV approach. The GFV can provide an overall variety value that may support river restoration decision‐making and planning, particularly when geomorphic complexity enhancement is a design objective. Analysing metric variety values with statistically significant hotspot cluster maps and complementary process‐based software and mapping applications allows variety correspondence to systematic feature changes to be assessed, providing an analytical approach for river morphology change comparison, channel design and geomorphic process restoration.
