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Few empirical data exist to examine the influence of regional scale environmental gradients on productivity patterns of plant species. In this paper we analyzed the productivity of several dominant grass species along two climatic gradients, mean annual precipitation (MAP) and mean annual temperature (MAT), in the Great Plains of the United States. We used climatic data from 296 weather stations, species production data from Natural Resource Conservation Service rangeland surveys and a geographic information system to spatially integrate the data. Both MAP and MAT were significantly related to annual above-ground net primary production (ANPP). MAP explained 54 % to 89 % of the variation in ANPP of two C4 short-grasses, Bouteloua gracilis and Buchloë dactyloides, and two C4 tall-grasses, Andropogon gerardii and Schizachyrium scoparium (= Andropogon scoparius). MAT explained 19 % to 41 % of the variation in ANPP of two C4 grasses, B. gracilis and B. dactyloides, and 41 % to 66 % of the variation in ANPP of two C3 grasses, Agropyron smithii and Stipa comata. ANPP patterns for species along both gradients were described by either linear, negative exponential, logistic, normal or skewed curves. Patterns of absolute ANPP (g/m2) for species differed from those of relative ANPP (%) along the MAP gradient. Responses were similar for species with common functional characteristics (e.g. short-grasses, tall-grasses, C3, C4). Our empirical results support asymmetric responses of species to environmental gradients. Results demonstrate the importance of species attributes, type of environmental gradient and measure of species importance (relative or absolute productivity) in evaluating ecological response patterns.

Weather in the Corn Belt and northern plains and the elimination of traditional commodity programs have refocused attention on farmland valuation. This study uses a statistical formulation of information provided by individual regressors to examine the sensitivity of farmland values to changes in inflation, returns on agricultural assets, and the cost of capital. The results indicate that inflation provides the most information on changes in farmland values; however, the regional results indicate that regions that tend to be more sensitive to changes in the return on agricultural assets also rely more heavily on government payments.

Pest risk maps are an important source of decision support when devising strategies to minimize introductions of invasive organisms and mitigate their impacts. When possible management responses to an invader include costly or socially sensitive activities, decision makers tend to follow a more certain (i.e. risk-averse) course of action. We present a new mapping technique that assesses pest invasion risk from the perspective of a risk-averse decision maker. We demonstrate the approach by evaluating the likelihood that an invasive forest pest will be transported to one of the continental US states or Canadian provinces in infested firewood that may be carried by visitors to US federal campgrounds. We test the impact of the risk aversion assumption using distributions of plausible pest arrival scenarios generated with a geographically explicit model developed from data documenting camper travel across the study area. Next, we prioritize regions of high and low pest arrival risk via application of two stochastic ordering techniques that employ, respectively, first- and second-degree stochastic dominance rules, the latter of which incorporates the notion of risk aversion. We then identify regions in the study area where incorporating risk aversion changes a region's pest risk value considerably. While both methods identified similar areas of highest and lowest risk, they differed in how they demarcated moderate-risk areas. Each method provides a tractable way to incorporate decision-making preferences into final risk estimates, and thus helps to better align these estimates with particular decision-making scenarios about an organism of concern. Overall, incorporation of risk aversion helps to refine the set of locations that could be confidently targeted for costly inspections and outreach activities.

This paper focuses on the development of the OKANOLA project to provide research, education and demonstration to stimulate the development of winter rape as a major profitable rotational crop with winter wheat in the Oklahoma and Kansas, USA. Information on the major insect pests of rape and winter wheat and the challenges in their management are also presented.

Oil concentration and fatty acid composition were determined in achenes of two annual Helianthus species (112 populations) and 11 perennial species (103 populations) from the Great Lakes region and the Central Great Plains of the U.S. The highest average oil concentration was observed in annual H. petiolaris Nutt. with 28.8%, followed by H. annuus L. with 25.4%. Among the perennial species, H. hirsutus Raf. had the highest average oil concentration with 29.8%. The highest average palmitic (C16: 0) and stearic (C18:0) fatty acids were observed in H. tuberosus L. (6.5 and 3.5%, respectively), while the lowest values were observed in H. pauciflorus Nutt. ssp. subrhomboideus (4.2 and 2.1, respectively). The highest oleic acid (C18:1) was observed in H. annuus (24.7%) and the highest linoleic (C18:2) was observed in H. pumilus Nutt. with 71.3%. Sufficient variability appears to be present in the wild species for enhancement of oil and fatty acid characteristics for cultivated sunflower. /// La concentración de aceite y la composición del ácido graso fueron determinados en aquenios de dos especies de Helianthus anuales (112 poblaciones) y 11 especies perennes (103 poblaciones) procedentes de la región de los Grandes Lagos y de las Grandes Planicies Centrales de los EE.UU. El promedio mayor de concentración de aceite se observó en la anual H. petiolaris Nutt. con 28,8%, seguida por H. annuus L. con 25,4%. Entre las especies perennes, la H. hirsutus Raf. tuvo el promedio mayor de concentración de aceite con 29,8%. El promedio mayor de concentración de ácidos grasos, palmítico (C16:0) y esteárico (C18:0) fueron observados en la H. tuberosus L. (6,5% y 3,5%, respectivamente), mientras los valores más bajos fueron observados en la H. pauciflorus Nutt. ssp. subrhomboideus (4,2 y 2,1, respectivamente). El mayor ácido oléico (C18:1) se observó en la H. annuus (24,7%) y el mayor ácido linoléico (C18:2) se observó en la H. pumilus Nutt. con 71,3%. Parece haber suficiente variabilidad en las especies silvestres, para lograr un mejoramiento de las características de aceite y ácido graso del girasol cultivado.

This chapter uses the lens of social-ecological resilience to understand community gardens in three very different locations, and how they may represent the rapidly growing community garden movement in different urban contexts in the Global North. The first case focuses on the burgeoning community gardens movement in Vienna, Austria, where gardening has a strong history and prominence in the urban landscape. The second case explores community gardening in the context of a small city in the agriculturally dominated Great Plains of the USA: Lincoln, Nebraska. The third case explores community gardens in New York City, to understand the function and meaning of community gardens, post-Hurricane Sandy. The physical space, embodied practices and communities of practice associated with these community gardens reflect their local context to support vital social-ecological functions ranging from generating local ecosystem services to cultivating community empowerment and bolstering food sovereignty.

Wheat, barley, flaxseed, and oilseed sunflower acreage respond to different economic variables. Wheat and barley acreage must be divided among program-complying, program-planted, and nonprogram-planted acreage because these categories respond to different variables and respond to own expected-revenue and price-risk variables in opposite ways. Flaxseed, sunflower, and nonprogram-planted acreage of wheat and barley have highly significant, positive responses to their own expected revenue and negative responses to their own-price risk. Flaxseed and sunflower acreage have been more responsive to their lagged values than to expected revenues for wheat.

Biotic response to the buildup of greenhouse gases in Earth's atmosphere is considerably more complex than an adjustment to changing temperature and precipitation. The fertilization effect CO2has on some plants, the impact UVB radiation has on health and productivity of organisms, and the resulting changes in competitive balance and trophic structure must also be considered. The intent of this paper is to review direct and indirect effects of anthropogenic greenhouse gases on wildlife, and to explore possible effects on populations of birds and their habitats in the northern Great Plains. Many of the potential effects of increasing greenhouse gases, such as declining plant nutritional value, changes in timing of insect emergence, and fewer and saltier wetlands, foreshadow a decline in avian populations on the Great Plains. However, other possible effects such as increased drought resistance and water use efficiency of vegetation, longer growing seasons, and greater overall plant biomass promise at least some mitigation. Effects of multiple simultaneous perturbations such as can be expected under doubled CO2scenarios will require substantial basic research to clarify.

This paper describes a range of state-level issues and responses to groundwater law. It begins with a description of groundwater law, both for the USA in general and for the three states (Kansas, Nebraska and Texas) in particular. It then follows with an account of groundwater allocation law problems faced by Kansas due to groundwater mining. The next section addresses groundwater issues and innovations in each state: (1) in Kansas, a water reuse project and an aquifer storage and recovery project; (2) in Nebraska, two types of interstate conflicts, one dealing with antiexportation statutes and the other dealing with allocation of an interstate river and the surface-groundwater interaction with that river; and (3) in Texas, questions about the continued efficacy of its Rule of Capture groundwater doctrine and about the advisability of moving groundwater long distances within the state.

This chapter presents the changing conditions of a subregion and a specific place embedded within the larger region (space) of the Great Plains. From a general overview of the Great Plains, through a discussion of a portion of its High Plains subregion, and ending with a specific Kansas community, the focus is on general economic and environmental conditions. While some places within the larger space of the North American Great Plains/prairie region may find the wherewithal to succeed in the longer term - by capitalizing on local features and local entrepreneurial strength - these are likely to be exceptional in a large and relatively sparsely populated region.