scholarly journals Early season grazing effects on birch, grass, herbs and plant litter in coastal meadows used by reindeer: a short-term case study

Rangifer ◽  
2002 ◽  
Vol 22 (2) ◽  
pp. 123 ◽  
Author(s):  
Svein M. Eilertsen ◽  
Ivar Schjelderup ◽  
Svein D. Mathiesen

The effects of short-term grazing by reindeer (Rangifer tarandus tarandus) on birch (Betula pubescens), grasses, herbs and plant litter in coastal meadows in spring were investigated in grazed and control plots in 1996 and 1997. The meadow contained 29 different plant species, all but one of which (Deschampsia caespitosa) were intensively grazed by reindeer. Young birch eaten by reindeer did not increase in mean height (9 cm), while birch protected from grazing grew from 9 to 22 cm (P<0.05) during the two years of the experiment. The ratio of grasses to herbs was higher (P<0.05) in the grazed plots than in the control plots, and the relative abundace of grasses increased during the summer in both years. The abundance of Rumex asetosa and Alchemilla subcrenata decreased (P<0.05) in response to grazing. From spring 1996, plant litter increased (P<0.05) on the control plots until the investigation came to an end in spring 1998, unlike grazed vegetation. Reindeer affects the coastal meadows in northern Norway in spring by browsing on birch and grazing on herbs and grass which in the long term might influence the cultural landscape in favour of the growth of grass species.

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Yi Ren ◽  
Alparslan Emrah Bayrak ◽  
Panos Y. Papalambros

We compare the performance of human players against that of the efficient global optimization (EGO) algorithm for an NP-complete powertrain design and control problem. Specifically, we cast this optimization problem as an online competition and received 2391 game plays by 124 anonymous players during the first month from launch. We found that while only a small portion of human players can outperform the algorithm in the long term, players tend to formulate good heuristics early on that can be used to constrain the solution space. Such constraining of the search enhances algorithm efficiency, even for different game settings. These findings indicate that human-assisted computational searches are promising in solving comprehensible yet computationally hard optimal design and control problems, when human players can outperform the algorithm in a short term.


Temida ◽  
2003 ◽  
Vol 6 (4) ◽  
pp. 3-13 ◽  
Author(s):  
Vesna Nikolic-Ristanovic

In this paper the author explores, focusing largely on the example of the Balkans, the connection between the expansion of neoliberal market economy and war, and related to it the growth of illegal markets and the shadow economy, on one hand, and the victimisation by human trafficking, on the other. By locating human trade within expanding local and global illegal markets, the author is arguing that, without taking into consideration wider social contexts, which create structural incentives for illegal markets and transnational organised crime, we can hardly understand the causes, let alone build effective strategies to combat and prevent it. Consequently, on the basis of the analyses of human trade as a form of both transnational organised crime and illegal markets, some strategies (short-term and long-term) for the prevention and control of human trafficking on both the micro and macro level are suggested.


2014 ◽  
Vol 39 (3) ◽  
pp. 77-85
Author(s):  
Harmen Janse ◽  
Kees van der Flier

Haiti was struck by a heavy earthquake in 2010 and international aid poured into the country. News reports in 2011 were not very positive about the results of post-disaster reconstruction: “The relief efforts are only putting Haiti on life-support instead of evolving into the next stage of development”. One of the non-governmental organisations (NGOs) involved in Haiti was Cordaid, implementing a ‘transitional shelter strategy’ to support the transformation of neigh-bourhoods from a state of life-support into a state of self-sustaining development. The strategy was implemented in both a rural and an urban area. The main feature of the strategy was the provision of structures that could be adapted from simple shelters to permanent houses. Since the results of the strategy were mixed and ambiguous, a comparative case study was conducted to evaluate the shelter strategy in both areas. The objective was to draw lessons about what has to be taken into account when formulating future urban shelter strategies. The case study is discussed in this article. The main finding from the case study is that producing the intended number of shelters within the financial and time budgets that were set (efficiency), was more difficult in the urban area than in the rural area. But the conditions for linking relief and development (effectiveness) are more favourable in the urban context. NGOs may achieve long-term (effective) results in the urban context when a lower efficiency can be justified. That is why NGOs need to engage in a debate about the extent to which they are able to focus on long-term shelter or housing strategies. The important element in the debate is communication with the donors who are often focused on short-term relief measures. However urban areas cannot be rebuilt with only short-term interventions. The link between relief and development has to be made by a process-orientated approach focusing on capacities of local participants.


2016 ◽  
Vol 5 (1) ◽  
pp. 26-41 ◽  
Author(s):  
Rebecca Hamilton ◽  
Diane Brown

Libraries are taking on new roles in a disaster and with that comes strategic responsibilities beyond traditional asset recovery activities. In the past, library disaster plans have emphasized recovery of materials. Here, the emphasis is on continuing business operations. Libraries have become the centers of communication for their communities in a crisis. This article will demonstrate the essential role of libraries before, during and after a disaster, both short term and long term and how to get a seat at the table with community planners by demonstrating the functions that are critical to recovery. A literature review and case study are used to develop these recommendations. A critical success factor is to use a disaster preparation methodology that includes a business continuity plan.


2016 ◽  
Vol 13 (24) ◽  
pp. 6651-6667 ◽  
Author(s):  
Jing Tang ◽  
Guy Schurgers ◽  
Hanna Valolahti ◽  
Patrick Faubert ◽  
Päivi Tiiva ◽  
...  

Abstract. The Arctic is warming at twice the global average speed, and the warming-induced increases in biogenic volatile organic compounds (BVOCs) emissions from Arctic plants are expected to be drastic. The current global models' estimations of minimal BVOC emissions from the Arctic are based on very few observations and have been challenged increasingly by field data. This study applied a dynamic ecosystem model, LPJ-GUESS, as a platform to investigate short-term and long-term BVOC emission responses to Arctic climate warming. Field observations in a subarctic tundra heath with long-term (13-year) warming treatments were extensively used for parameterizing and evaluating BVOC-related processes (photosynthesis, emission responses to temperature and vegetation composition). We propose an adjusted temperature (T) response curve for Arctic plants with much stronger T sensitivity than the commonly used algorithms for large-scale modelling. The simulated emission responses to 2 °C warming between the adjusted and original T response curves were evaluated against the observed warming responses (WRs) at short-term scales. Moreover, the model responses to warming by 4 and 8 °C were also investigated as a sensitivity test. The model showed reasonable agreement to the observed vegetation CO2 fluxes in the main growing season as well as day-to-day variability of isoprene and monoterpene emissions. The observed relatively high WRs were better captured by the adjusted T response curve than by the common one. During 1999–2012, the modelled annual mean isoprene and monoterpene emissions were 20 and 8 mg C m−2 yr−1, with an increase by 55 and 57 % for 2 °C summertime warming, respectively. Warming by 4 and 8 °C for the same period further elevated isoprene emission for all years, but the impacts on monoterpene emissions levelled off during the last few years. At hour-day scale, the WRs seem to be strongly impacted by canopy air T, while at the day–year scale, the WRs are a combined effect of plant functional type (PFT) dynamics and instantaneous BVOC responses to warming. The identified challenges in estimating Arctic BVOC emissions are (1) correct leaf T estimation, (2) PFT parameterization accounting for plant emission features as well as physiological responses to warming, and (3) representation of long-term vegetation changes in the past and the future.


2019 ◽  
Vol 125 ◽  
pp. 01003 ◽  
Author(s):  
Wesley Beek ◽  
Bart Letitre ◽  
H. Hadiyanto ◽  
S. Sudarno

The Water as Leverage project aims to lay a blueprint for urban coastal areas around the world that are facing a variety of water-related issues. The blueprint is based upon three real case studies in Bangladesh, India and Indonesia. The case of Indonesia focuses on Semarang, a city that faces issues like flooding, increased water demand, and a lack of wastewater treatment. In this report I summarise the different techniques available to tackling these issues. Along with this I provide a cost-benefit analysis to support decision makers. For a short term it is recommended to produce industrial water from (polluted) surface water as a means to offer an alternative to groundwater abstraction. On a long term it is recommended to install additional wastewater and drinking water treatment services to facilitate better hygiene and a higher quality of life.


Author(s):  
Clony Junior ◽  
Pedro Gusmão ◽  
José Moreira ◽  
Ana Maria M. Tome

Data science highlights fields of study and research such as time series, which, although widely explored in the past, gain new perspectives in the context of this discipline. This chapter presents two approaches to time series forecasting, long short-term memory (LSTM), a special kind of recurrent neural network (RNN), and Prophet, an open-source library developed by Facebook for time series forecasting. With a focus on developing forecasting processes by data mining or machine learning experts, LSTM uses gating mechanisms to deal with long-term dependencies, reducing the short-term memory effect inherent to the traditional RNN. On the other hand, Prophet encapsulates statistical and computational complexity to allow broad use of time series forecasting, prioritizing the expert's business knowledge through exploration and experimentation. Both approaches were applied to a retail time series. This case study comprises daily and half-hourly forecasts, and the performance of both methods was measured using the standard metrics.


Author(s):  
Guangwen Bi ◽  
Chuntao Tang ◽  
Bo Yang

Elimination of soluble boron will be a challenge to reactor operation for PWR. This paper is to promote a control strategy of soluble boron-free operation for a small PWR, through selection of burnable poison (BP), BP loading and control rod loading, based on the reactivity balance and manage requirement. The analysis for on-power operation and shutdown condition indicated that this strategy could be suitable for long-term and short-term reactivity and power distribution control for soluble boron-free operation.


Author(s):  
J. Douglas Hill ◽  
Paul Moore

Nuclear power plants rely on Instrumentation and Control (I&C) systems for control, monitoring and protection of the plant. The original, analog designs used in most nuclear plants have become or soon will be obsolete, forcing plants to turn to digital technology. Many factors affect the design of replacement equipment, including long-term and short-term economics, regulatory issues, and the way the plant operates on a day-to-day basis. The first step to all modernization projects should involve strategic planning, to ensure that the overall long and short-term goals of the plant are met. Strategic planning starts with a thorough evaluation of the existing plant control systems, the available options, and the benefits and consequences of these options.


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