scholarly journals The Theory of Island Biogeography on the Hawaiki Archipelago

2021 ◽  
Author(s):  
◽  
Khoi Dinh
Keyword(s):  
Exotic Species ◽  
Island Biogeography ◽  
Native Species ◽  
Physical Geography ◽  
Geographical Information ◽  
Similar Species ◽  
North East ◽  
The North ◽  
Theory Of Island Biogeography ◽  
Negative Effect

<p>This thesis addresses MacArthur and Wilson‟s Theory of Island Biogeography (1967) on a set of islands around the north-east coast of the North Island of New Zealand. The flora species lists from these islands were obtained from both published and unpublished island surveys whilst Geographical Information Systems (GIS) techniques were utilised in order to calculate the physical geography of islands.  These islands were an ideal study site for such research because they display natural gradients in both physical geography as well as native and exotic species richness. The literature on the Theory of Island Biogeography has yet to comprehensively understand the differences between the patterns of exotic richness and native richness. Furthermore, the importance of studies on exotics species is increasingly relevant given the negative effect they have had on native communities worldwide.  The results of my research illustrated that there were similar species-area and species-isolation relationships between exotic and native species. These two relationships were also consistent with what is expected under classical island biogeography principles. Interestingly however, I found that distance from the mainland had a stronger negative effect on exotics species. There were a significantly lower proportion of exotics with increasing isolation.  This result has applicable outcomes for conservation management on the Hawaiki archipelago. I suggested that weeding effort focus on larger islands and in particular the islands closer to the mainland. Globally, the biogeographical patterns of exotic species are still poorly examined. With insights from this study and other similar research the Theory of Island Biogeography may be an informative approach to dealing with the ominous threat of exotic species.</p>

scholarly journals The Theory of Island Biogeography on the Hawaiki Archipelago

2021 ◽  
Author(s):  
◽  
Khoi Dinh
Keyword(s):  
Exotic Species ◽  
Island Biogeography ◽  
Native Species ◽  
Physical Geography ◽  
Geographical Information ◽  
Similar Species ◽  
North East ◽  
The North ◽  
Theory Of Island Biogeography ◽  
Negative Effect

<p>This thesis addresses MacArthur and Wilson‟s Theory of Island Biogeography (1967) on a set of islands around the north-east coast of the North Island of New Zealand. The flora species lists from these islands were obtained from both published and unpublished island surveys whilst Geographical Information Systems (GIS) techniques were utilised in order to calculate the physical geography of islands.  These islands were an ideal study site for such research because they display natural gradients in both physical geography as well as native and exotic species richness. The literature on the Theory of Island Biogeography has yet to comprehensively understand the differences between the patterns of exotic richness and native richness. Furthermore, the importance of studies on exotics species is increasingly relevant given the negative effect they have had on native communities worldwide.  The results of my research illustrated that there were similar species-area and species-isolation relationships between exotic and native species. These two relationships were also consistent with what is expected under classical island biogeography principles. Interestingly however, I found that distance from the mainland had a stronger negative effect on exotics species. There were a significantly lower proportion of exotics with increasing isolation.  This result has applicable outcomes for conservation management on the Hawaiki archipelago. I suggested that weeding effort focus on larger islands and in particular the islands closer to the mainland. Globally, the biogeographical patterns of exotic species are still poorly examined. With insights from this study and other similar research the Theory of Island Biogeography may be an informative approach to dealing with the ominous threat of exotic species.</p>

scholarly journals The socio-economic determinants of social capital and the mediating effect of history: Making Democracy Work revisited

2013 ◽  
Vol 54 (1) ◽  
pp. 48-73 ◽  
Author(s):  
Emanuele Ferragina
Keyword(s):  
Social Capital ◽  
Collective Action ◽  
Middle Ages ◽  
Historical Analysis ◽  
Mediating Effect ◽  
The South ◽  
Economic Determinants ◽  
North East ◽  
The North ◽  
Negative Effect

Putnam argued that the different levels of social capital between the North and the South of Italy originated in the Middle Ages. In the North of Italy, the existence of a dense network of medieval towns gave rise to horizontal ties and collective action. Conversely, in the South of Italy, the authoritarian Norman rule generated hierarchical relationships and the absence of collective action. This article proposes an alternative explanation for the lack of social capital in the South of Italy using a comparative perspective. The analysis is undertaken in two steps: 1) testing the socio-economic determinants of social capital in 85 European regions; 2) performing a comparative historical analysis between deviant – that is, South of Italy and Wallonia – and regular – that is, North East of Italy and Flanders – cases. These cases are selected by looking at the residual of the regression model. The results suggest that medieval history does not explain the lack of social capital in the South of Italy. On the contrary, the historical legacy mitigates the negative effect of inequitable income distribution, low labour market participation and weak national cohesion on social capital.

The distribution of three eyeless Chaetozone species (Cirratulidae: Polychaeta) in the north-east Atlantic

2007 ◽  
Vol 87 (5) ◽  
pp. 1111-1114 ◽  
Author(s):  
S.J. Chambers ◽  
E.L. Dominguez-Tejo ◽  
J.M. Mair ◽  
L.A. Mitchell ◽  
A. Woodham
Keyword(s):  
Information System ◽  
World Wide ◽  
System Analysis ◽  
Distribution Patterns ◽  
Wide Distribution ◽  
Geographical Information ◽  
East Atlantic ◽  
North East ◽  
The North ◽  
Water Characteristics

Geographical information system analysis was applied to assist in the re-identification of records of Chaetozone setosa from the north-east Atlantic. Previously this species was considered to have a world-wide distribution. The aim of this study is to clarify and illustrate the distribution patterns associated with sediment and water characteristics of C. setosa and other Chaetozone species.

scholarly journals Study of elite black currant varieties selected at the Federal Agrarian Scientific Centre of the North-East

2021 ◽  
pp. 5-10
Author(s):  
N. S. Vakhrusheva ◽  
T. I. Saltykova ◽  
A. P. Sofronov
Keyword(s):  
Powdery Mildew ◽  
High Resistance ◽  
Control Sample ◽  
Black Currant ◽  
High Productivity ◽  
North East ◽  
The North ◽  
Good Taste ◽  
Negative Effect ◽  
Region 10

Elite varieties of black currant selected at the Federal Agrarian Scientific Centre of the North-East were studied with the purpose of identifying samples with an optimal combination of high productivity, large fruit, good taste, resistance to big bud mite and powdery mildew. The studies were carried out in 2015–2019 on a site located in the central agro-climatic zone of the Kirov region. 10 elite black currant varieties of 2013 planting were investigated. The varieties of Arkadiya and Vologda were used as control. The counts and observations were carried out using conventional methods. The combination of high productivity, its sustainability and high self-fertility was noted in varieties 71-2-07, 65-1-07 and 64-4-07. In terms of resistance to the pest, two highly resistant samples 71-2-07 and 65-1-07 were identified, which showed no signs of damage during the study period. The damage by big bud mite remained low across the entire experimental site. The average negative effect of big bud mite on the yield was found (r = -0.48). In the following 7 elite forms — 71-2-07, 65-1-07, 70-5-07, 46-1-07, 12-1-07, 15-1-07, 20-1-07 (70.0 % of the studied material), the maximum degree of damage by powdery mildew did not exceed 1.0 points, which indicates their high resistance. The combination of high resistance to big bud mites and resistance to powdery mildew was found in varieties 71-2-07 and 65-1-07. During the study period, 9 elite black currant varieties produced large-fruited berries. Out of these 9 forms, 3 (71-2-07, 64-4-07, 12-1-07) showed significantly higher values of this indicator compared to the Vologda control. Sample 27-1-07 was distinguished by a combination of large fruit, good taste and low acidity, as well as by high contents of ascorbic acid and dry matter. Sources of economically valuable traits were identified in 2 samples: 65-1-07 having a combination of high productivity, large fruit, high self-fertility, good taste, resistance to big bud mites and powdery mildew; 64-4-07 having a combination of high productivity, large fruit and high self-fertility. These genotypes can be recommended as a starting material for further breeding. On the basis of the results obtained, the Ariel variety (71-2-07) was forwarded to the State Variety Testing in 2020.

scholarly journals Assessment of groundwater quality using geographical information system (GIS), at north-east Cairo, Egypt

2015 ◽  
Vol 14 (2) ◽  
pp. 325-339
Author(s):  
M. F. El-Shahat ◽  
M. A. Sadek ◽  
W. M. Mostafa ◽  
K. H. Hagagg
Keyword(s):  
Information System ◽  
Groundwater Quality ◽  
Geographical Information System ◽  
Groundwater Resources ◽  
Geographical Information ◽  
Quaternary Aquifer ◽  
North East ◽  
The North ◽  
Groundwater Samples ◽  
Almost All

The present investigation has been conducted to delineate the hydrogeochemical and environmental factors that control the water quality of the groundwater resources in the north-east of Cairo. A complementary approach based on hydrogeochemistry and a geographical information system (GIS) based protectability index has been employed for conducting this work. The results from the chemical analysis revealed that the groundwater of the Quaternary aquifer is less saline than that of the Miocene aquifer and the main factors that control the groundwater salinity in the studied area are primarily related to the genesis of the original recharging water modified after by leaching, dissolution, cation exchange, and fertilizer leachate. The computed groundwater quality index (WQI) falls into two categories: fair for almost all the Miocene groundwater samples, while the Quaternary groundwater samples are all have a good quality. The retarded flow and non-replenishment of the Miocene aquifer compared to the renewable active recharge of the Quaternary aquifer can explain this variation of WQI. The index and overlay approach exemplified by the DUPIT index has been used to investigate the protectability of the study aquifers against diffuse pollutants. Three categories (highly protectable less vulnerable, moderately protectable moderately vulnerable and less protectable highly vulnerable) have been determined and areally mapped.

scholarly journals Securing Access to Drinking Water in North-Eastern Morocco: The Example of the Taourirt-Oujda Corridor

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 928
Author(s):  
Halima Jounaid ◽  
Taha Attou ◽  
Toufik Remmal ◽  
Aimad Bouaziz
Keyword(s):  
Drinking Water ◽  
Water Supply ◽  
Surface Waters ◽  
Groundwater Resources ◽  
Drinking Water Supply ◽  
Geographical Information ◽  
North East ◽  
The North ◽  
North Eastern ◽  
Eastern Morocco

Taourit-Oujda corridor (T.O.C.) is a geological entity of north-eastern Morocco with a total area of 4000 Km2. The drinking water supply in this arid region still faces challenges that meet a growing demand for a shortage of fresh water. This shortage is mainly due to the scarcity and irregularity of the precipitations, the overexploitation of the water resources, and the decrease of the capacity of storage dams that are the main source of drinking water supply in this area. This work aims at estimating deficit (to 2040) for drinking water provided by Machraa Hammadi dam and proposing favourable drilling sites to strengthen drinking water supply through the identification of groundwater resources that can be used in quantity and quality. To do this, a multi-criteria analysis (MCA) covering geological, hydrogeological and hydro-chemical aspects using the Geographical Information System (GIS) was carried out. This study shows that T.O.C. aquifer is more productive in the south-west of it, in the centre near the El Aioun municipality and in the north-east at the town of Sidi Bouhouria. According to Moroccan standards, defining the quality norms of surface waters, waters destined for irrigation, and of surface waters used for the production of drinking water, the groundwater in the center and north-east areas is also with good to medium overall quality groundwater.

scholarly journals A GIS based approach for the prediction of the dam break flood hazard – A case study of Zardezas reservoir “Skikda, Algeria”

2015 ◽  
Vol 27 (1) ◽  
pp. 15-20 ◽  
Author(s):  
Oussama Derdous ◽  
Lakhdar Djemili ◽  
Hamza Bouchehed ◽  
Salah Eddine Tachi
Keyword(s):  
Land Use Planning ◽  
Flood Hazard ◽  
Flow Simulation ◽  
Dam Break ◽  
Geographical Information ◽  
Hydraulic Modelling ◽  
North East ◽  
The North ◽  
Potential Failure ◽  
Gis Environment

Abstract The construction of dams in rivers can offer many advantages, however the consequences resulting from their failure could result in major damage, including loss of life and property destruction. To mitigate the threats of dam break it is essential to appreciate the characteristics of the potential flood in realistic manner. In this study an approach based on the integration of hydraulic modelling and GIS has been used to assess the risks resulting from a potential failure of Zardezas dam, a concrete dam located in Skikda, in the North East of Algeria. HEC-GeoRAS within GIS was used to extract geometric information from a digital elevation model and then imported into HEC-RAS. Flow simulation of the dam break was performed using HEC-RAS and results were mapped using the GIS. Finally, a flood hazard map based on water depth and flow velocity maps was created in GIS environment. According to this map the potential failure of Zardezas dam will place a large number in people in danger. The present study has shown that Application of Geographical Information System (GIS) techniques in integration with hydraulic modelling can significantly reduce the time and the resources required to forecast potential dam break flood hazard which can play a crucial role in improving both flood disaster management and land use planning downstream of dams.

scholarly journals Trophic niche partitioning between two native and two exotic carnivores in SW Portugal

Web Ecology ◽  
2007 ◽  
Vol 7 (1) ◽  
pp. 53-62 ◽  
Author(s):  
M. J. Santos ◽  
B. M. Pinto ◽  
M. Santos-Reis
Keyword(s):  
Exotic Species ◽  
Native Species ◽  
Human Mobility ◽  
Niche Partitioning ◽  
Home Range Size ◽  
Trophic Niche ◽  
Exclusion Principle ◽  
Feeding Strategies ◽  
Similar Species ◽  
Negative Effects

Abstract. The introduction of exotic species is one of the most pervasive consequences of the increased human mobility. The most known negative effects are the decrease or extinction of natives. The common-genet, Genetta genetta, and the Egyptian mongoose, Herpestes ichneumon, were introduced in the Iberian Peninsula in the 15th and 19th centuries, respectively. The competitive exclusion principle defines that two ecologically similar species cannot coexist. Thus, some degree of partitioning has to occur in species realized niche, which can occur at the trophic level. To test this hypothesis of partitioning we compared the diet of these two exotic species with that of two native species (stone marten, Martes foina, and red fox, Vulpes vulpes). The results show a high degree of overlap (>45%) between the diets of species similar in their feeding strategies (arboreal and ground feeding). Nonetheless, at the finer scale of prey consumed at the species level some differences are found between the native and exotic species. These results suggest that if coexistence is due to trophic niche partitioning it only occurs at the level of the consumed species. However, coexistence may also be due to a combination of different strategies (home-range size, time and space use) that structured the different realized niches of each species.

scholarly journals From 1900 to 2000: History of Earthworm taxonomy in the North and Northeast of Brazil and its current distribution in Brazilian Biomes

2020 ◽  
Vol 51 (3) ◽  
pp. 21-29
Author(s):  
Sandriel Costa Sousa ◽  
Luis Manuel Hernández-García ◽  
Martin Lindsey Christoffersen
Keyword(s):  
New Species ◽  
Exotic Species ◽  
Current Distribution ◽  
Native Species ◽  
Northeastern Brazil ◽  
Review Of The Literature ◽  
Slow Pace ◽  
The Past ◽  
The North ◽  
History Of

One of the initial milestones for earthworm taxonomy was the work of Michaelsen (1900), “Das Tierreich Oligochaeta”. During this period only two exotic species of the genus Amynthas were recorded for the North and Northeast of Brazil. A century has passed and little is known about the taxonomy of earthworms in these two regions and the distribution of these organisms in Brazilian Biomes. The Brazilian territory is divided into six large biomes, Amazonian, Caatinga, Cerrado, Atlantic Forest, Pampa, and Wetlands. Little is known about the distribution of earthworms in these environments. This article provides a review of the literature on the progress of taxonomy in northern and northeastern Brazil over a century and provides the current distribution of earthworms in Brazilian biomes. In the first four decades the taxonomy has advanced at a slow pace, with only 19 new species recorded. With the beginning of Gilberto Righi’s work, earthworm taxonomy has advanced significantly. After Righi’s death in 1999, taxonomy in the North and Northeast has only begun breathing again within the past two years, in which the description of nine new species and two new genera have appeared. There are currently 174 species distributed in thirteen of the sixteen states that make up the North and Northeast regions of Brazil. Regarding distribution, the Amazon, Mata Atlantica and Cerrado biomes stand out for being the most diverse in genera and species, while the Caatinga, Pampa and Pantanal biomes are less diversified. In addition, the Caatinga and Pampa are the only biomes having more exotic species than native species.

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