Search

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ten years ago, Garrott and Oli ([6]) stated that the US Bureau of Land Management's (BLM) Wild Horse and Burro Program was facing a critical crossroads. Moving forward: Integrating ecology into equid legislation Feral equids are simultaneously treated as wild, livestock, and pet populations. At the time, the abundance of feral equids on BLM lands was estimated at approximately 40,000 individuals, or approximately 13,000 more than the agency-determined maximum appropriate management level (AML; BLM [2]). Furthermore, the BLM has funded research on the development and application of fertility control, as well as on interactions between equids and their environments (BLM [2]). [Extracted from the article]

Operational satellite remote sensing products are transforming rangeland management and science. Advancements in computation, data storage and processing have removed barriers that previously blocked or hindered the development and use of remote sensing products. When combined with local data and knowledge, remote sensing products can inform decision‐making at multiple scales.We used temporal convolutional networks to produce a fractional cover product that spans western United States rangelands. We trained the model with 52,012 on‐the‐ground vegetation plots to simultaneously predict fractional cover for annual forbs and grasses, perennial forbs and grasses, shrubs, trees, litter and bare ground. To assist interpretation and to provide a measure of prediction confidence, we also produced spatiotemporal‐explicit, pixel‐level estimates of uncertainty. We evaluated the model with 5,780 on‐the‐ground vegetation plots removed from the training data.Model evaluation averaged 6.3% mean absolute error and 9.6% root mean squared error. Evaluation with additional datasets that were not part of the training dataset, and that varied in geographic range, method of collection, scope and size, revealed similar metrics. Model performance increased across all functional groups compared to the previously produced fractional product.The advancements achieved with the new rangeland fractional cover product expand the management toolbox with improved predictions of fractional cover and pixel‐level uncertainty. The new product is available on the Rangeland Analysis Platform (https://rangelands.app/), an interactive web application that tracks rangeland vegetation through time. This product is intended to be used alongside local on‐the‐ground data, expert knowledge, land use history, scientific literature and other sources of information when making interpretations. When being used to inform decision‐making, remotely sensed products should be evaluated and utilized according to the context of the decision and not be used in isolation. [ABSTRACT FROM AUTHOR]

The emergence of large-scale fire classifications and products informed by remote sensing data has enabled opportunities to include variability or heterogeneity as part of modern fire regime classifications. Currently, basic fire metrics such as mean fire return intervals are calculated without considering spatial variance in a management context. Fire return intervals are also only applicable at a particular grain size (defined as the spatial unit of interest) even though they are typically applied homogeneously. In this study, we utilized a 29-yr fire occurrence database to show how spatial variance changes with respect to grain as postulated by Wiens (1989) when reporting fire patterns within the Great Plains, USA. We utilized data from the Monitoring Trends in Burn Severity database of fire occurrence for the years 1984-2012. We analyzed median numbers of fire along with their variance at four spatial grains ranging from small units (e.g., plots at 3 9 3 km resolution) to large units (e.g., landscapes at 1500 9 2700 km resolution). Median number of fire occurrences was consistently low, irrespective of grain. Despite the consistency in low median numbers of fires across grain, variance in the numbers of fires between units decreased. Variance within units, however, did not change as grain increased indicating fire-pattern-scale inconsistencies. Fire pattern interpretations depended entirely on the scale at which it is calculated. Given that the Great Plains region has a large disparity in fire patterns (i.e., some regions burn often, while others may never burn), fire regime classifications will benefit from including scale-specific variance estimates as a foundation for understanding changes in fire regimes and corresponding social-ecological and policy responses. [ABSTRACT FROM AUTHOR]

Management for biodiversity and other ecosystem services from North America's rangelands has received increasing attention as recognition of the societal value of those services and payment mechanisms for them have grown. This, combined with adverse effects of livestock management on North American rangeland biodiversity and predictions of a warmer and drier climate reducing rangeland productivity, has led some rangeland scientists to call for a paradigm shift from utilitarian-driven management to biodiversity conservation management. A challenge for rangeland science is to describe management changes required for this shift and to elucidate consequent ecological and economic tradeoffs. On the basis of two criteria, direct alteration of biodiversity and alteration of one or more drivers of biodiversity, a framework of ten ecological conditions is proposed for making the transition from livestock-centered management toward biodiversity-centered management on Great Plains rangelands: (1) composition and productivity of plant communities; (2) herbivory patterns; (3) fire regimes; (4) habitat contiguity; (5) stream hydrology; (6) temporal ecological variability; (7) herbivorous mammal communities; (8) fate of ungulate production; (9) apex predators; and (10) size of management units. Reflecting trends in rangelands elsewhere around the world, a shift toward management for biodiversity on the Great Plains may be facilitated by changes underway in land ownership and by a potentially increasing number of landowners for whom livestock production is of secondary importance to lifestyle and natural amenity benefits from the land. [ABSTRACT FROM AUTHOR]

Before planting millions of hectares to switchgrass (Panicum virgatum L.) monocultures for producing biomass feedstock for biorefineries, it has been proposed that monocultures be tested against polycultures so, among other issues, the economics of both systems can be compared. This research was conducted to determine the lowest cost lignocellulosic biomass feedstock production system from among four monocultures and four polycultures. Randomized complete block designs with four replications were established at two Oklahoma locations. Plots were managed to represent anticipated production activities if perennial species were established in a low input system and harvested once a year to produce biorefinery feedstock. The four monocultures included switchgrass, sand bluestem (Andropogon hallii Hack.), Old World bluestem (OWB) (Bothriochloa ischaemum L. Keng), and big bluestem (A. gerardii Vitman). The four polycultures included mixtures of four grasses, four grasses and four forbs, eight grasses and eight forbs, and OWB with alfalfa (Medicago sativa L.). Plots were harvested once a year for 3 yr. For every treatment that included a mix of species, a dominant species emerged by the third harvest, suggesting that over time these treatments may not differ greatly from monocultures with minor representation of other species. The average yield was 4.6 Mg ha-1yr-1 for treat- ments seeded as monocultures at one location compared with 4.0 Mg ha-1yr-1 for the treatments seeded as polycultures. At the second location, monocultures averaged 7.9 Mg ha-1yr-1 and polycultures 6.5 Mg ha-1yr-1. Economics favored monocultures for the location and environmental conditions that occurred during the time period studied. [ABSTRACT FROM AUTHOR]

This article focuses on the effects of fire and grazing on wind erosion, soil water content, and soil temperature. The physical, chemical, and biotic properties of soil may be altered by fire through numerous complex processes across spatial and temporal scales. Among the potential changes are erosion rates, soil temperature, and soil water content. Each of these factors may affect nutrient cycling and productivity of above and below-ground resources. Additionally, wind erosion can reduce air quality. Highly preferential grazing of burned sites has been confirmed for cattle and fire effects may be exacerbated by intensive herbivores. Wildfires rarely respect pasture boundaries, being of irregular shape and generally smaller than the average pasture in the western United States. Following wildfire, the burned area may be fenced, or the remainder of the pasture burned to prevent concentrated herbivores on burned patches.

Focuses on land cover and landscape pattern changes in an area of northwestern Oklahoma. Features of the U.S. Conservation Reserve Program; Factors responsible for the increase in juniper woodlands and mixed woodlands.

Presents a study which proposes a paradigm which enhances heterogeneity instead of homogeneity to promote biological diversity and wildlife habitat on rangelands grazed by livestock. Topic of how many animals and plants which are dependent on rangelands are imperiled in the United States; Potential causes for the decline in grassland bird populations; View that traditional rangeland management approach is incapable of providing an ecological framework for alternative management objectives.

ABSTRACT.--Wallows are circular soil depressions created by repeated bison (Bison bison L.) dust-bathing. Despite more than a century of bison absence from the Great Plains and lack of evidence on wallow persistence, many studies have classified grassland soil depressions as `relict' wallows. We studied bison wallowing on a tallgrass prairie site in Oklahoma where bison were reestablished in late 1993. Bison use of existing soil depressions fitting descriptions for relict wallows located before reintroduction and bison formation of new active wallows were documented from 1993-1995. Bison avoided existing depressions, instead forming active wallows in different locations. Bulk density and soluble salt, sodium and clay content of soils in existing depressions were significantly higher than soils in active wallows or nearby reference sites. These depressions occurred primarily on shale-derived soils rich in silt and clay, whereas active wallows were formed mostly on sandy loam soils overlying sandstone. The spatial distribution and soil conditions of these depressions suggested pedogenic, rather than animal disturbance, origins. Soil sampling beneath the depressions revealed a dense clay lens located above a natric (high exchangeable sodium content) horizon, both of which were absent from soils in nearby reference sites. Natric soil horizons, known as claypans, are formed by pedologic processes common to soils derived from marine shales. Thus, these soil depressions, and possibly other `relict' bison wallows, are not persistent soil disturbances resulting from bison wallowing, but small patches of landscape and soil heterogeneity resulting from variation in underlying geological materials. [ABSTRACT FROM AUTHOR]

Studies of thermal selection by organisms, including fishes, are common and provide data that are useful for conservation and management. Advances in temperature sensing technology have improved these studies; however, the benefits of new technology (e.g., increased accuracy and greater deployment flexibility) should be carefully considered and compared to disadvantages (e.g., higher costs and training requirements). Fiber-optic distributed temperature sensing (FO-DTS) has become more common in aquatic applications and may provide a novel and useful method of relating thermal patchiness to habitat selection by fishes or other aquatic organisms. We present a case study using FO-DTS to conduct a microhabitat-scale resource selection study using stream fishes of the Ozark Highland ecoregion in the south-central United States. We describe the setup and deployment of FO-DTS and how it was integrated into traditional microhabitat survey methods at three stream sites that were repeatedly surveyed over consecutive days. We successfully used FO-DTS to characterize thermal selection by Neosho Bass Micropterus velox at our sites and conclude that the technology would be applicable to similar, microhabitat-scale evaluations. We then compare costs, benefits, and disadvantages of FO-DTS to other sensing methods that could have been used to complete our study. We found that FO-DTS provided accurate measures and greater coverage compared to most alternatives but that equipment costs were far greater. We provide suggestions for additional fisheries applications where FO-DTS may be useful while acknowledging that in some instances, the upfront costs of the technology may outweigh the potential benefits. • We compare temperature selection using fiber-optic distributed temperature sensing and cheaper and less precise alternatives. • We describe set up and use of the fiberoptic distributed temperature sensing system in an aquatic environment. • The benefits of the fiberoptic system relate to coverage and precision but are much more costly upfront. • The fiberoptic system may be useful in dynamic environments or where species are sensitive to small temperature changes. [ABSTRACT FROM AUTHOR]

Studies habitat characteristics affecting lark sparrow nest-site selection and nest success in a southern mixed-grass prairie in Oklahoma. Background to the study; Methods; Results and discussion.

The article focuses on the impact that oil and gas extraction technologies have had in reducing ecosystem services in crop and rangelands in the Great Plains region. It states that satellite-derived net primary production, the amount of carbon fixed by plants and accumulated as biomass, has declined as a result of oil and gas activity from 2000 through 2015. It comments on the impact of hydraulic fracturing on water quality and water use regimes and the need for land use policy reforms.

While prescribed burning is a proven tool in the management of forests and grasslands, its use has been limited due, in part, to potential risks that may result in legal liability, property damage, and personal injury. The purpose of this study is to understand the factors that shape landowners' and fire professionals' perceptions of risks associated with prescribed burning activities. The data for this study were collected from active prescribed fire professionals involved in Prescribed Burn Association (PBA) activities in 14 Southern and Mid-western states. Perceived risk was higher among respondents with higher levels of concern related to safety and weather but lower among respondents with more experience in burning activities. Sociodemographic variables such as age and income were not significantly correlated with risk perception. These findings are useful for better understanding how landowners and fire professionals perceive risk and offer insight into how perceived risk affects decisions to apply prescribed burns., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Grasslands are among the most imperilled biomes of the world. Identifying the most appropriate framework for restoring grasslands is dependent on the objectives of restoration, which is inherently determined by human priorities. Debates over the appropriate conservation model for grasslands have often focused on which species of herbivores should be the focus of restoration efforts. Here we discuss three perspectives of herbivore-based conservation in North American grasslands. First, the Pleistocene rewilding perspective is based upon the idea that early humans contributed to the demise of megafauna that were important to the evolution and development of many of North America's grasslands; therefore, their aim of restoration is rewilding of landscapes to pre-human times. Second, the bison rewilding perspective considers American bison a keystone herbivore that is culturally and ecologically important to North American grasslands. A third perspective focuses on restoring the pattern and processes of herbivory on grasslands and is less concerned about which herbivore is introduced to the landscape. We evaluate each of these three conservation perspectives in terms of a framework that includes a human domain, an herbivore domain and a biophysical domain. While all conservation perspectives partly address the three domains, they all fall short in key areas. Specifically, they fail to recognize that past, current and future humans are intimately linked to grassland patterns and processes and will continue to play a role in structuring grasslands. Furthermore, these perspectives seem to only superficially consider the role of fragmentation and climate change in influencing grassland patterns and processes. As such, we argue that future grassland conservation efforts must depend on the development of a model that better integrates societal, economic and policy objectives and recognizes climate change, fragmentation and humans as an integral part of these ecosystems.This article is part of the theme issue 'Trophic rewilding: consequences for ecosystems under global change'., (© 2018 The Author(s).)

Ecological theory predicts that diversity decreases variability in ecosystem function. We predict that, at the landscape scale, spatial variability created by a mosaic of contrasting patches that differ in time since disturbance will decrease temporal variability in aboveground plant biomass. Using data from a multi-year study of seven grazed tallgrass prairie landscapes, each experimentally managed for one to eight patches, we show that increased spatial variability driven by spatially patchy fire and herbivory reduces temporal variability in aboveground plant biomass. This pattern is associated with statistical evidence for the portfolio effect and a positive relationship between temporal variability and functional group synchrony as predicted by metacommunity variability theory. As disturbance from fire and grazing interact to create a shifting mosaic of spatially heterogeneous patches within a landscape, temporal variability in aboveground plant biomass can be dampened. These results suggest that spatially heterogeneous disturbance regimes contribute to a portfolio of ecosystem functions provided by biodiversity, including wildlife habitat, fuel, and forage. We discuss how spatial patterns of disturbance drive variability within and among patches.