scholarly journals Estimation of Forest Disturbance from Retrospective Observations in a Broad-Scale Inventory

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1298
Author(s):  
John W. Coulston ◽  
Christopher B. Edgar ◽  
James A. Westfall ◽  
Marcus E. Taylor
Keyword(s):  
Forest Disturbance ◽  
Effective Management ◽  
Forest Disturbances ◽  
Sample Weight ◽  
Policy Responses ◽  
The Us ◽  
Proper Estimation ◽  
True Population ◽  
Broad Scale ◽  
Better Than

Understanding the extent and timing of forest disturbances and their impacts is critical to formulating effective management and policy responses. Broad-scale inventory programs provide key estimates of forest parameters that indicate the extent and severity of disturbance impacts. Here, we review the use of a post-stratified estimator in a panelized design, in the context of disturbance observations that are collected retrospectively. We further develop a sample weight adjustment that is requisite for proper estimation of the extent and timing of disturbances. Using populations from areas of Arkansas, California, and Maine in the US, the weight adjustment technique was tested in a Monte Carlo simulation. We found that the estimated area of disturbance using the weight adjustment technique had satisfactory agreement with the true population values and performed considerably better than the conventional post-stratified estimation approach. The proliferation of panelized forest inventory designs globally suggests that accurate estimates of areal extent and timing of disturbances will often require that weighting adjustment techniques be employed in the estimation process.

A comparison of hierarchical models for relative catch efficiency based on paired-gear data for US Northwest Atlantic fish stocks

2013 ◽  
Vol 70 (9) ◽  
pp. 1306-1316 ◽  
Author(s):  
Timothy J. Miller
Keyword(s):  
Size Effects ◽  
Hierarchical Models ◽  
Northwest Atlantic ◽  
Fish Stocks ◽  
Gear Design ◽  
The Us ◽  
Conditional Beta ◽  
Binomial Models ◽  
Random Pair ◽  
Better Than

Selectivity and catch comparison studies are important for surveys that use two or more gears to collect relative abundance information. Prevailing model-based analytical methods for studies using a paired-gear design assume a binomial model for the data from each pair of gear sets. Important generalizations include nonparametric smooth size effects and normal random pair and size effects, but current methods for fitting models that account for random smooth size effects are restrictive, and observations within pairs may exhibit extra-binomial variation. I propose a hierarchical model that accounts for random smooth size effects among pairs and extra-binomial variation within pairs with a conditional beta-binomial distribution. I compared relative performance of models with different conditional distribution and random effects assumptions fit to data on 16 species from an experiment carried out in the US Northwest Atlantic Ocean comparing a new and a retiring vessel. For more than half of the species, conditional beta-binomial models performed better than binomial models, and accounting for random variation among pairs in the relative efficiency was important for all species.

Martin Shapiro: An Appreciation

The Forum ◽  
2016 ◽  
Vol 14 (2) ◽  
Author(s):  
R. Shep Melnick
Keyword(s):  
Institutional Environment ◽  
Empirical Studies ◽  
The Political ◽  
Public Officials ◽  
Thick Description ◽  
Past Half Century ◽  
The Us ◽  
The Matrix ◽  
The One ◽  
Better Than

AbstractOver the past half century no judicial politics scholar has been more respected or influential than Martin Shapiro. Yet it is hard to identify a school of thought one could call “Shapiroism.” Rather than offer convenient methodologies or grand theories, Shapiro provides rich empirical studies that show us how to think about the relationship between law and courts on the one hand and politics and governing on the other. Three key themes run through Shapiro’s impressive oevre. First, rather than study courts in isolation, political scientists should view them as “one government agency among many,” and seek to “integrate the judicial system in the matrix of government and politics in which it actually operates.” Law professors may understand legal doctrines better than political scientists, but we know (or should know) the rest of the political system better than they do. Second, although judges inevitably make political decisions, their institutional environment leads them to act differently from other public officials. Most importantly, their legitimacy rests on their perceived impartiality within the plaintiff-defendant-judge triad. The conflict between judges’ role as impartial arbiter and enforcer of the laws of the regime can never be completely resolved and places powerful constraints on their actions. Third, the best way to understand the complex relationship between courts and other elements of the regime is comparative analysis. Shapiro played a major role in resuscitating comparative law, especially in his work comparing the US and the EU. All this he did with a rare combination of thick description and crisp, jargon-free analysis, certainly a rarity the political science of our time.

scholarly journals Gangguan Hutan di KPH Kuningan Divisi Regional Jawa Barat dan Banten

2019 ◽  
Vol 10 (3) ◽  
pp. 159-165
Author(s):  
Ati Dwi Nurhayati ◽  
Liana Arhami
Keyword(s):  
Forest Fires ◽  
Forest Disturbance ◽  
Forest Products ◽  
Forest Disturbances ◽  
Community Based ◽  
Forest Protection ◽  
Pests And Diseases ◽  
Legal Remedies ◽  
Preventive Actions ◽  
And Control

Forest protection is an effort to prevent and control the destruction of forests, forest areas, and forest products caused by human actions, livestock, fires, pests and diseases. The aims of this research are to identify the types of forest disturbance especially those caused by humans and physically, analyze the factors causing forest disturbance, and analyze efforts to control forest disturbance at KPH Kuningan. Forest disturbances that occurred in the KPH Kuningan during 2010-2014 included: timber theft, forest fires, forest encroachment, and natural disasters. The background of forest disturbance in the Kuningan KPH is mainly due to the socio-economic conditions of the community around the forest that are still low. Strategic actions taken to prevent forest disturbance at the KPH Kuningan are to take pre-emptive actions in the form of counseling and establish good relations between officers and the community through social communication and Community Based Forest Management (PHBM), preventive actions in the form of patrols and safeguards against forest potential, and repressive actions in the form of legal remedies against the perpetrators. Key words: cause of forest disturbance, type of forest disturbance, forest disturbance control

Phenology Modelling and Forest Disturbance Mapping with Sentinel-2 time series in Austria

2020 ◽  
Author(s):  
Markus Löw ◽  
Koukal Tatjana
Keyword(s):  
Time Series ◽  
Bark Beetle ◽  
Forest Ecosystems ◽  
Forest Disturbance ◽  
Spatial Scales ◽  
Data Access ◽  
Forest Monitoring ◽  
Forest Disturbances ◽  
Disturbance Dynamics ◽  
Sentinel 2

Abstract Background Worldwide, forests provide natural resources and ecosystem services. However, forest ecosystems are threatened by increasing forest disturbance dynamics, caused by direct human activities or an altering natural environment. It is decisive to trace the intra- to trans-annual dynamics of these forest ecosystems. National to local forest communities request detailed area-wide maps that delineate forest disturbance dynamics at various spatial scales. Methods We developed a remote sensing based time series analysis (TSA) framework that comprises data access, data management, image pre-processing, and an advanced but flexible TSA. The data basis is a dense time series of multispectral Sentinel-2 images with a spatial resolution of 10 metres. We use a dynamic Savitzky-Golay-filtering approach to reconstruct robust but sensitive phenology courses. Deviations from the latter are further used to derive spatiotemporal information on forest disturbances. In a first case study, we apply the TSA to map forest disturbances directly or indirectly linked to recurring bark beetle infestation in Northern Austria. Finally, we use zonal statistics on different spatial scales to provide aggregated information on the extent of forest disturbances between 2018 and 2019.Results and Conclusion The outcomes are a) individual phenology models and deduced phenology metrics for each 10 metres by 10 metres forest pixel in Austria and b) forest disturbance maps useful to investigate the occurrence, development and extent of bark beetle infestation. The phenology modelling results provide area-wide consistent data, also useful for downstream analyses (e.g. forest type classification). Results of the forest disturbance detection demonstrate that the TSA is capable to systematically delineate disturbed forest areas. Information derived from such a forest monitoring tool is highly relevant for various stakeholders in the forestry sector, either for forest management purposes or for decision-making processes on different levels.

Antibiotic Treatment—Much Better than Nothing

2019 ◽  
pp. 135-154
Author(s):  
Janet R. Gilsdorf
Keyword(s):  
Clinical Trials ◽  
Bacterial Meningitis ◽  
Antibiotic Treatment ◽  
Animal Experiments ◽  
Effective Management ◽  
Basic Principles ◽  
Duration Of Therapy ◽  
The Past ◽  
Drug Doses ◽  
Better Than

Over the past five decades, many animal experiments as well as clinical trials of antibiotics in humans treated for meningitis have defined the levels of antibiotics that are present in infected meninges and in the blood, thus informing the drug doses necessary to successfully treat the infection. In spite of the different kinds of bacteria that cause meningitis and the availability of various antibiotics to treat it, several basic principles of effective management for all common forms of bacterial meningitis have emerged from the decades of research. As a result of these studies, most children with meningitis in America receive appropriate antibiotic treatment (the correct antibiotic and the correct dose for the correct duration of therapy), and their outcomes are much, much better than the disastrous outcomes of earlier eras.

Links between Domestic and Regional Security

2018 ◽  
pp. 23-42
Author(s):  
Kristian Coates Ulrichsen
Keyword(s):  
Identity Politics ◽  
Persian Gulf ◽  
Oil Prices ◽  
Regional Security ◽  
Fiscal Stress ◽  
Policy Responses ◽  
The Us ◽  
Other World ◽  
The Persian Gulf ◽  
The Arab Spring

This chapter examines the myriad linkages between domestic and regional security and how these are evolving across the Persian Gulf. The Persian Gulf noticeably did not share in the evolution of security structures that took place in other world regions such as Eastern Europe or Latin America during the 1980s and 1990s. Instead, the fallout from the US-led invasion and occupation of Iraq in 2003 and policy responses to the Arab Spring in 2011 led to the growth of what Kristian Coates Ulrichsen labels a “geopolitical straitjacket” that contributed to the rise of sectarian identity politics and the emergence of the dangerous new threat from ISIS. Coates Ulrichsen details the policy dilemmas that ISIS presents to policymakers in GCC states who face the additional pressure of having to take sensitive decisions against the backdrop of a potentially prolonged period of low oil prices and fiscal stress.

A method for creating a burn severity atlas: an example from Alberta, Canada

2020 ◽  
Vol 29 (11) ◽  
pp. 995
Author(s):  
Ellen Whitman ◽  
Marc-André Parisien ◽  
Lisa M. Holsinger ◽  
Jane Park ◽  
Sean A. Parks
Keyword(s):  
Forest Regeneration ◽  
Forest Disturbance ◽  
Google Earth ◽  
Burn Severity ◽  
Primary Forest ◽  
Surface Reflectance ◽  
Short Term ◽  
Automated Mapping ◽  
The Us ◽  
Development And Validation

Wildland fires are globally widespread, constituting the primary forest disturbance in many ecosystems. Burn severity (fire-induced change to vegetation and soils) has short-term impacts on erosion and post-fire environments, and persistent effects on forest regeneration, making burn severity data important for managers and scientists. Analysts can create atlases of historical and recent burn severity, represented by changes in surface reflectance following fire, using satellite imagery and fire perimeters. Burn severity atlas production has been limited by diverse constraints outside the US. We demonstrate the development and validation of a burn severity atlas using the Google Earth Engine platform and image catalogue. We automated mapping of three burn severity metrics using mean compositing (averaging reflectance values) of pixels for all large (≥200ha) fires in Alberta, Canada. We share the resulting atlas and code. We compared burn severity datasets produced using mean compositing with data from paired images (one pre- and post-fire image). There was no meaningful difference in model correspondence to field data between the two approaches, but mean compositing saved time and increased the area mapped. This approach could be applied and tested worldwide, and is ideal for regions with small staffs and budgets, and areas with frequent cloud.

Frequency Distributions for Hourly and Daily Clearness Indices

2001 ◽  
Author(s):  
Manuel Ibañez ◽  
William A. Beckman ◽  
Sanford A. Klein
Keyword(s):  
Solar Radiation ◽  
Recent Literature ◽  
Weather Data ◽  
Clearness Index ◽  
Frequency Distributions ◽  
The Us ◽  
Daily Frequency ◽  
Better Than ◽  
Exponential Probability

Abstract The clearness index for hourly and daily radiation is an important parameter in describing solar radiation. Liu and Jordan demonstrated that the monthly average daily clearness index could be used to predict the long-term distribution of daily solar radiation in a month. This paper reviews recent literature on the prediction of hourly and daily frequency distributions and cumulative frequency distributions of clearness indices. Ten years of measured weather data for six cities in the US are used to investigate the nature of the hourly and daily frequency distributions. A second set of ten years of data for six cities is used to verify the predictions. A bi-exponential probability density function is proposed that fits the observed bimodal nature of the data better than existing models. A case is made for the function being universal.

Chapter II. The World Economy

1989 ◽  
Vol 128 ◽  
pp. 20-39
Author(s):  
R.J. Barrell ◽  
Andrew Gurney
Keyword(s):  
Industrial Production ◽  
World Economy ◽  
Commodity Prices ◽  
Oil Prices ◽  
Short Term ◽  
Developed Country ◽  
Policy Responses ◽  
The Us ◽  
The World ◽  
Early Indicators

Our February forecast suggested that developments in the short term would be dominated by fears of accelerating inflation and policy responses to them. This has indeed been the case. In Japan, Germany and the US wholesale prices have begun to rise relatively rapidly. Although commodity prices, especially of metals and minerals and of developed country foods, have fallen in recent weeks, at least in dollar terms they remain high and oil prices appear to have hit temporary peaks at the beginning of the quarter. These developments are the result of demand pressure. Our equations for real commodity prices, which were reported in the August 1988 issue of the Review, do have rather strong influences from world industrial production in then. As commodity prices are more timely than figures for demand and output they have often been early indicators of rising demand and we believe that they are currently, and correctly, filling this role.

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