scholarly journals Analysis of the Performance of two Rangeland Protocols, Monitoring and Assessment

2016 ◽  
Vol 5 (2) ◽  
pp. 47
Author(s):  
Soumana Idrissa ◽  
Ása L. Aradóttir ◽  
Sigþrúður Jónsdóttir

<p>This study compared and contrasted data from the stick and modified Braun-Blanquet monitoring protocols in three areas with different land use histories: an unrestored barren area, a young and old restored areas. The study areas are part of extensive degraded of birch woodland and willow shrubland that have partly been re-vegetated.Vegetation and site characteristics were assessed in the three areas using the two protocols and soil sampling to characterize the ecological status of a land that has been re-vegetated. The analysis of the two protocols data indicates similar tendency which is the improvement of the ecological condition of the restored areas compared to the unrestored area. The soil carbon and nitrogen contents increased when the pH decreased with the restoration age. The improvement is better at the old restored area which has received more fertilization compared to the young restoration. Stick method estimated greater cover of vascular plants, litters, mosses and rocks, and lower amount of bare ground than modified Braun-Blanquet. The two protocols provided similar estimates cover of lichens and sedges. Stick method also provided three supplementary indicators which were not included in modified Braun-Blanquet: plants base, basal and canopy gaps. Another observation that could be proved by further studies, stick seemed to be more precise and economical than modified Braun-Blanquet. The indicators provided by the two protocols were related to the three attributes of ecosystems and the rangelands health indicators. This study is a preliminary that cannot be able to recommend one method, but it advocates stick method to assess and monitor vegetation dominated by herbaceous layer as grassland and modified Braun-Blanquet for the one dominated by woody layer.</p>

2021 ◽  
Vol 17 (2) ◽  
pp. 186-203
Author(s):  
Nathan Genicot

AbstractThe COVID-19 pandemic has given rise to the massive development and use of health indicators. Drawing on the history of international public health and of the management of infectious disease, this paper attempts to show that the normative power acquired by metrics during the pandemic can be understood in light of two rationales: epidemiological surveillance and performance assessment. On the one hand, indicators are established to evaluate and rank countries’ responses to the outbreak; on the other, the evolution of indicators has a direct influence on the content of public health policies. Although quantitative data are an absolute necessity for coping with such disasters, it is critical to bear in mind the inherent partiality and precarity of the information provided by health indicators. Given the growing importance of normative quantitative devices during the pandemic, and assuming that their influence is unlikely to decrease in the future, they call for close scrutiny.


2014 ◽  
Vol 22 (1) ◽  
pp. 43-48
Author(s):  
Ivan Stankoci ◽  
Jana Jariabková ◽  
Viliam Macura

Abstract The ecological status of a river is influenced by many factors, of which the most important are fauna and flora; in this paper they are defined as a habitat. During the years 2004, 2005, 2006 and 2011, research on the hydroecological quality of a habitat was evaluated in the reference section of the Drietomica River. Drietomica is a typical representative river of the Slovak flysch area and is located in the region of the White Carpathians in the northwestern part of Slovakia. In this article the results of modeling a microhabitat by means of the Instream Flow Incremental Methodology (IFIM) are presented. For the one-dimensional modeling, the River Habitat Simulation System (RHABSIM) was used to analyse the interaction between a water flow, the morphology of a riverbed, and the biological components of the environment. The habitat ´s hydroecological quality was evaluated after detailed ichthyological, topographical and hydro-morphological surveys. The main step was assessing the biotic characteristics of the habitat through the suitability curves for the Brown trout (Salmo trutta m. fario). Suitability curves are a graphic representation of the main biotic and abiotic preferences of a microhabitat´s components. The suitability curves were derived for the depth, velocity, fish covers and degree of the shading. For evaluating the quality of the aquatic habitat, 19 fish covers were closely monitored and evaluated. The results of the Weighted Usable Area (WUA = f (Q)) were evaluated from a comprehensive assessment of the referenced reach of the Drietomica River.


2006 ◽  
Vol 86 (6) ◽  
pp. 1443-1447 ◽  
Author(s):  
D. Fourgon ◽  
G. Lepoint ◽  
I. Eeckhaut

Analyses of the natural abundance of carbon and nitrogen stable isotopes were performed to investigate the feeding habits of two ophiuroids, Ophiomastix venosa and Ophiocoma scolopendrina, and to assess the potential benefit obtained by the symbiotic Ophiomastix venosa juveniles. A tracer experiment was also carried out to clarify the contribution of algae to the nitrogen uptake amongst the tested ophiuroids. Our results suggest that Ophiocoma scolopendrina adults occupy a higher position in the food web than Ophiomastix venosa and mainly feed on neuston. In contrast, O. venosa adults feed on the alga Sargassum densifolium and on organic matter associated with sediment. Free juveniles and symbiotic juveniles of O. venosa have intermediate δ13C values between both adult species. The high proportion of 13C in the symbiotic juveniles compared to the one in their conspecific adults indicates that their diet slightly differs from the latter and is closer to that of Ophiocoma scolopendrina. This raises the hypothesis that symbiotic juveniles steal neuston from their associated host, O. scolopendrina.


Author(s):  
Ximing Deng ◽  
Shutao Chen ◽  
Chunhua Lv ◽  
Kai Yang ◽  
Dongyao Shang ◽  
...  

2016 ◽  
Vol 13 (22) ◽  
pp. 6273-6284 ◽  
Author(s):  
Shuhua Yi ◽  
Jianjun Chen ◽  
Yu Qin ◽  
Gaowei Xu

Abstract. There is considerable controversy about the effects of plateau pika (Ochotona curzoniae, hereafter pika) on alpine grassland on the Qinghai-Tibet Plateau (QTP). On the one hand, pika is considered a keystone species. On the other hand, it is being poisoned. Although significant efforts have been made to study the effects of pika at a quadrat scale ( ∼  m2), our knowledge about its distribution and effects at a larger scale is very limited. In this study, we investigated the direct effects, i.e., burying and grazing, of pika by upscaling field sampling at a quadrat scale to a plot scale ( ∼  1000 m2) by aerial photographing. Altogether 168 plots were set on four different types of alpine grassland in a semiarid basin on the QTP. Results showed that (1) the effects of pika pile burying on the reduction of vegetation cover, biomass, soil carbon, and nitrogen were less than 10 %, which was much smaller than the effects of bald patches; and (2) pika consumed 8–21 % of annual net primary production of grassland. We concluded that the direct burying and grazing effects of pika on alpine grassland were minor in this region. The quadcopter is an efficient and economic tool for long-term repeated monitoring over large regions for further understanding the role of pika.


2007 ◽  
Vol 539-543 ◽  
pp. 4105-4110
Author(s):  
Ji Hyun Yoon ◽  
Bong Sang Lee ◽  
Eui Pak Yoon

The objective of this investigation was to correlate the chemical composition of welding rods for gas tungsten arc welding with the fracture resistance and tensile properties of type 347 welds through the systematic tests and microstructural analyses. Five weld metals which differed in contents of carbon, nitrogen and niobium each other and a high δ-ferrite containing weld metal were deposited by the six different welding rods. J-R fracture resistance and tensile properties were evaluated for the type 347 welds. The microstructural examinations were performed to relate key microstructural features to mechanical properties. It was found that the contents of Nb(C,N) precipitates in type 347 welds were determined by the mixed function of carbon and nitrogen and niobium contents in welding rods. The strengths of type 347 welds were in direct proportion to the contents of Nb(C,N) and J-R fracture resistances were inversely proportional to the contents of Nb(C,N). It was concluded that the type 347 weld with high fracture resistance and adequate strength was obtainable by controlling the sum of carbon and nitrogen contents near 0.1wt% and a limitation of the carbon content below 0.04 wt% in welding rod.


Author(s):  
N. Blazhko

Reviewed the current state of wetland landscape systems (PLC) Lviv region. Highlighted areas PLC of good ecological status, with a satisfactory ecological condition and unsatisfactory environmental conditions. Key words: overmoistened landscape systems (OLS)peat, peat, drainage improvement, environmental stabilizing factors, environmental destabilizing factors.


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