The Personal Interview

Rangeland and pastures comprise about 42% of the total land area of the United States. About three-quarters of all domestic livestock depend upon grazing lands for survival. Many ranges have had domestic stock grazing for more than 100 years and, as a result, the plant composition has changed greatly from the original ecosystems. Western rangelands previously dominated by perennial bunchgrasses have been converted, primarily through overgrazing, to annual grasslands that are susceptible to invasion by introduced dicots. Today there are more than 300 rangeland weeds in the United States. Some of the most problematic include Bromus tectorum, Euphorbia esula, Centaurea solstitialis, C. diffusa, C. maculosa, and a number of other Centaurea species. In total, weeds in rangeland cause an estimated loss of $2 billion annually in the United States, which is more than all other pests combined. They impact the livestock industry by lowering yield and quality of forage, interfering with grazing, poisoning a...

Invasive weeds in rangelands: Species, impacts, and management

While the impacts of high exploitation on fish populations and aquatic ecosystems are well-documented for commercial fishing, particularly in the marine environment, the potential biological impacts of angling received less attention. This paper discusses angling patterns within a framework of basic ecological and evolutionary literature and examines potential biological impacts of angling by focusing on study results associated with high exploitation rates and pronounced selective exploitation. The impacts range from impacts occurring directly on the exploited species (truncation of the natural age and size structure, depensatory mechanisms, loss of genetic variability, evolutionary changes), to those that occur on the aquatic ecosystem (changes in trophic cascades, trait-mediated effects). As a third category, impacts related to the angling activity per se are distinguished (habitat modifications, wildlife disturbance, nutrient inputs, loss of fishing gear). Although the main threats to fish often are l...

/pdf/documented-and-potential-biological-impacts-of-recreational-5g4y7w5t9c.pdf

Documented and Potential Biological Impacts of Recreational Fishing: Insights for Management and Conservation

We postulate that the causes of the problem of invasive alien species are primarily economic and, as such, require economic solutions. Invasive alien species are of increasing concern for four reasons. First, introductions are increasing sharply, while mechanisms for excluding or eradicating alien species have been either withdrawn or progressively weakened. Both trends are due to the liberalization of and increase in international travel and trade, an economic phenomenon. Second, the costs of invasions are rising rapidly due partly to increasing human population density, and partly to increasing intensity of production in genetically impoverished agricultural systems. Third, biological invasions are associated with a high degree of uncertainty both because they involve novel interactions, and because invasion risks are endogenous. Actual risks depend on how people react to the possibility of invasions. Fourth, the exclusion and control of invasive species is a "weakest-link" public good. This places the well-being of society in the hands of the least effective provider. We argue that an economic solution to the problem of invasive species has two components. One is to use incentives to change human behavior so as to enhance protection against the introduction, establishment, and spread of invasive behavior. The other is to develop institutions that support the weakest members of global society, converting a "weakest-link" to a "best-shot" public good.

/pdf/biological-invasion-risks-and-the-public-good-an-economic-vbhb9dlkav.pdf

Biological invasion risks and the public good: an economic perspective

Wetlands are highly productive ecosystems, providing a number of goods and services that are of value to people. The open-access nature and the public-good characteristics of wetlands often result in these regions being undervalued in decisions relating to their use and conservation. There is now a substantial literature on wetland valuation, including two meta-analyses that examine subsets of the available wetland valuation literature. We collected over 190 wetland valuation studies, providing 215 value observations, in order to present a more comprehensive meta-analysis of the valuation literature that includes tropical wetlands (e.g., mangroves), estimates from diverse valuation methodologies, and a broader range of wetland services (e.g., biodiversity value). We also aim for a more comprehensive geographical coverage. We find that socio-economic variables, such as income and population density, that are often omitted from such analyses are important in explaining wetland value. We also assess the prospects for using this analysis for out-of-sample value transfer, and find average transfer errors of 74%, with just under one-fifth of the transfers showing errors of 10% or less.

/pdf/the-empirics-of-wetland-valuation-a-comprehensive-summary-39dtawbbgk.pdf

The Empirics of Wetland Valuation: A Comprehensive Summary and a Meta-Analysis of the Literature

https://www.tandfonline.com/doi/pdf/10.1080/07349165.1996.9725915

Economic effect of leafy spurge in the upper great plains: methods, models, and results

The economic impact of three invasive, exotic weeds--diffuse, spotted, and Russian knapweed (Centaurea diffusa, C. maculosa, and Acroptilon repens)--on Montana's economy was estimated using a procedure developed for another invasive weed species. Published data and that from a survey of county weed boards were used to estimate direct negative impacts of over $14 million annually due to infestation of over 2 million acres of rangeland and wildland. This amounts to about $10.63 on each infested grazing land acre and $3.95 on each infested wildland acre. Direct plus secondary economic impacts, estimated using an input-output model, are about $42 million annually, which could support over 500 jobs in the state's economy. This first approximation suggests the knapweed infestation problem in Montana deserves attention, although more work could be done to refine these estimates and to allow estimation of the impacts at sub-state levels.

The impact of knapweed on montana's economy

Dollar values were estimated for four prairie potholes and a wetland complex in North Dakota. Assessing these values required careful consideration of the ecological values and the societal values on a sitespecific basis. Assessments of value were made from four perspectivesowner, user, regional, and social. Values ofspecific outputs and total values varied among the five study sites. Annualper hectare values variedfrom the $10 owner value for the Nome wetland to the $921 regional value for the Alice wetland. The greatest analytical obstacle to obtaining more refined estimates was the physical and biological data needed to technically quantify wetland functions (e.g., groundwater recharge rates, groundwater flow paths andflow rates, runoffwater storage capacity, impacts ofrunofftiming on flood synchronization, and sedimentation rates). The perceived worth of wetlands has increased rapidly over the past two decades (Heimlich 1991) as society, "educated" by special interest groups, has come to consider that wetlands provide a wide range of social benefits. These social benefits include floodwater retention, sediment entrapment, nutrient assimilation, aquatic habitat, and terrestrial habitat (U.S. Department of Transportation 1983; U.S. Fish and Wildlife Service 1984; Amacher et al. 1989; Stavins 1990). Increasingly aware of these social benefits and of continued wetland conversions, many emphasize carefully considering the fate of remaining wetlands. Such consideration includes objective assessments of their economic worth to society, especially when

Empirical Valuation of Prairie Potholes: Five Case Studies

Economic Effect of Leafy Spurge in the Upper Great Plains: Methods, Models, and Results

Leafy spurge is a serious problem because of the speed with which it spreads and the difficulty of controlling it with available means. A rangeland economics model was developed to estimate the economic impacts of leafy spurge infestation on both ranchers and regional economies. A leafy spurge-induced carrying capacity reduction of about 580,000 animal unit months (AUMs), or enough for 77,000 cows, reduced ranchers annual net income nearly $9 million. Ranchers did not spend another $14 million on input costs, which reduced regional business activity. The regional impacts are about $75 million in reduced business activity for all sectors. These impacts on rancher incomes and regional economies suggest the potential economic returns of leafy spurge control could be substantial. Nomenclature: Leafy spurge (Euphorbia esula L. # EPHES). Additional index words: Regional impacts, rangeland, income, EPHES.

Economic impact of leafy spurge (Euphorbia esula) in North Dakota

Popular Tasks used by Researchers

How can I help with your research?

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

We encountered an error while loading the panel. Please try refreshing the page.

Something went wrong

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

Anyone with the link can view this chat. You can switch it back to private anytime.

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Jay A. Leitch

Author Tools

Chat about Author