scholarly journals Dragonfly Conservation in the Increasingly Stressed African Mediterranean-Type Ecosystems

2021 ◽  
Vol 9 ◽  
Author(s):  
Rassim Khelifa ◽  
Charl Deacon ◽  
Hayat Mahdjoub ◽  
Frank Suhling ◽  
John P. Simaika ◽  
...  

Freshwater habitats worldwide are experiencing many threats from environmental and anthropogenic sources, affecting biodiversity and ecosystem functioning. In Africa, particularly in Mediterranean climate zones, rapid human population growth is predicted to have great impact on natural habitats besides naturally occurring events such as unpredictable drought frequency and severity. Here, we analyze the potential correlation between odonate assemblage conservation priority (measured with the Dragonfly Biotic Index: DBI) and the magnitude of climate change and human perturbation in African regions with a dominant Mediterranean climate, namely Northern (NAR: Morocco, Algeria and Tunisia) and Southern African region (SAR: South Africa). Using a compilation of studies assessing odonate assemblages in lotic and lentic habitats of both regions (295 sites in NAR and 151 sites in SAR), we estimated DBI, temporal change in average annual temperature (T), annual precipitation (P), and human footprint index (HFI) in each site, then we tested whether sites with different levels of DBI were associated with different magnitudes of climatic and anthropogenic change. We estimated past (between 1980–1999 and 2000–2018) and future changes (between 1980–1999 and 2081–2100) in T and P based on three CMIP6 scenarios representing low (SSP126), moderate (SSP245), and high emission (SSP585), as well as the change in HFI from 1993 to 2009. We found that assemblages with higher DBI (i.e. higher conservation priority) encountered lower increase in T and slightly greater decrease in P than assemblages with lower DBI (i.e. lower conservation priority) in NAR during 1980–2018, but are projected to experience higher increase in T and lower decrease in P in future projections for 2081–2100. In SAR, the increase in T was mostly similar across assemblages but the decline in P was higher for assemblages with higher DBI during 1980–2018 and 2081–2100, suggesting that assemblages of higher conservation priority in SAR are threatened by drought. While HFI showed an overall increase in NAR but not in SAR, its temporal change showed only minor differences across assemblages with different DBI levels. We discuss the importance of management plans to mitigate the effects of climatic and anthropogenic threats, so improving conservation of odonate assemblages in these regions.

2018 ◽  
Vol 61 (3) ◽  
pp. 305-320 ◽  
Author(s):  
Yi Mei Tan ◽  
Justine E. Saunders ◽  
Siti Maryam Yaakub

AbstractSeagrass habitats provide a range of goods and benefits to coastal communities by supporting ecosystem functioning, food provisioning, and cultural values. However, they are at risk worldwide from anthropogenic activities, climate change impacts and limited resources, which hamper efforts to protect them. Effective conservation planning requires prioritisation of sites based on multiple factors, including their relative value and vulnerability (VU). The current study examines the efficacy of combining two well-established approaches – ecosystem service assessments and habitat VU analyses – to test a method for determining conservation priority for selected seagrass meadows in Southeast Asia. Seven seagrass meadows around Southeast Asia were selected and scored by the authors based on (1) the cumulative contribution of 12 ecosystem services (ES) and the condition of the meadows, (2) VU from 16 anthropogenic threats, which were each ranked against five factors (spatial scale, frequency, functional impact, resistance and recovery time) and (3) the combination of the two approaches to create a single numerical index. Prioritisation of sites differed when meadows were scored solely for the ES they provide, compared to how vulnerable they are to anthropogenic threats. The new combined analysis brought the two metrics together to give conservation priority to sites where management intervention will yield maximum conservation benefits from conservation effort, and resulted in the prioritisation of three sites: Barrang Lompo (Indonesia), Cape Bolinao (Philippines) and Beting Tanjung Kupang (Malaysia). This method is easy to use and does not require great technical expertise. It is also auditable, allowing for clear and transparent understanding of decision-making process.


2021 ◽  
Author(s):  
Fulya Aydin-Kandemir ◽  
Aynur Demir

Abstract Sultan Marshes is one of Turkey's Ramsar wetlands and has faced significant threats in recent years. Although the water was brought from other basins for restoration, observed temporal human-induced impacts and the current drought have damaged the wetland qualities of the Marshes. In this study, the temporal change of the Marshes and the human-induced effects are analyzed. Spatiotemporal surface water area (1984-2020) and whole land use changes (1990-2018) are evaluated with the temporal change of the Human Development, Global Terrestrial Human Footprint, and Ecological Footprint Indexes. The land use changes since 1990 reveal how the wetland has lost its functions. Especially between 1990-2000, the water area largely shifted into the sandy and swampy areas. In the swampy areas between 1990-2000, natural pasture formation was also observed in 2000. In addition, it is found that mining fields were constructed in the region between 1990-2000, albeit relatively small. According to the study, the most remarkable change occurred in the 1990-2000 period, considering the entire study timeline (1990-2018). In this period, there was also a transformation into irrigated agricultural lands around the national park. Moreover, there was a transformation from orchards and pasture areas to irrigated agricultural areas. When the changes in the wetland are evaluated with the human footprint data for 1993 and 2009, it was found that human impact was more substantial, especially in 1993 compared to 2009. This is in line with the continuous increase in HDI values between 1990 (0.54) and 2018 (0.81). Besides, the ecological footprint has increased since 1983. After 1983, the biocapacity in the region has steadily decreased to negative values.


2020 ◽  
Vol 5 ◽  

Human leukocyte antigen (HLA) loci are highly polymorphic and determine differential features of the immune response in subjects from different regions. HLA genes have been proposed to determine genetic susceptibility to several diseases, particularly to viral infections. Moreover, it has been suggested that each ethnic group could have a different specificity of T-lymphocyte reactivity to the same viral infections. In this review, we analyzed the distribution of HLA types in countries of the Asian, European and North African region. Also, we studied the relation between these HLA polymorphisms and susceptibility to infection by the coronavirus. Our findings indicated that homozygosity would increase susceptibility to viral infections and, in some cases, to coronavirus infection. HLA types showing higher susceptibility were reported in Asian population, including China, Singapore, and Taiwan. In contrast, lower susceptibility HLA variants were detected among African populations, some Asian populations, and Mediterranean populations. The presented evidence along with the spread pattern of COVID-19 infection suggests that HLA genetic variants might be related to its infection susceptibility and severity. The investigation of HLA genetic variants distribution would be a useful tool to predict different populations’ susceptibility to viral infections.


2020 ◽  
Vol 648 ◽  
pp. 111-123
Author(s):  
C Layton ◽  
MJ Cameron ◽  
M Tatsumi ◽  
V Shelamoff ◽  
JT Wright ◽  
...  

Kelp forests in many regions are experiencing disturbance from anthropogenic sources such as ocean warming, pollution, and overgrazing. Unlike natural disturbances such as storms, anthropogenic disturbances often manifest as press perturbations that cause persistent alterations to the environment. One consequence is that some kelp forests are becoming increasingly sparse and fragmented. We manipulated patch size of the kelp Ecklonia radiata over 24 mo to simulate persistent habitat fragmentation and assessed how this influenced the demography of macro- and microscopic juvenile kelp within the patches. At the beginning of the experiment, patch formation resulted in short-term increases in E. radiata recruitment in patches <1 m2. However, recruitment collapsed in those same patches over the extended period, with no recruits observed after 15 mo. Experimental transplants of microscopic and macroscopic juvenile sporophytes into the patches failed to identify the life stage impacted by the reductions in patch size, indicating that the effects may be subtle and require extended periods to manifest, and/or that another life stage is responsible. Abiotic measurements within the patches indicated that kelp were less able to engineer the sub-canopy environment in smaller patches. In particular, reduced shading of the sub-canopy in smaller patches was associated with proliferation of sediments and turf algae, which potentially contributed to the collapse of recruitment. We demonstrate the consequences of short- and longer-term degradation of E. radiata habitats and conclude that habitat fragmentation can lead to severe disruptions to kelp demography.


Author(s):  
I.G.C. Kerr ◽  
J.M. Williams ◽  
W.D. Ross ◽  
J.M. Pollard

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.


2020 ◽  
Vol 28 (Supplement) ◽  
pp. 86-109
Author(s):  
Kehinde Ibrahim

The judgments of the ECOWAS Court, which are final and immediately binding, are vital for the realisation of ECOWAS aims and objectives. The enforcement of its judgments is particularly important in the case of individuals whose enjoyment of fundamental human rights, as guaranteed under the ECOWAS Community laws, is dependent on effective enforcement. Yet, an existential puzzling paradox emanates through a poor record in the implementation of the ECOWAS Court's judgments. This problem, which is not limited to the West African region deserves scrutiny and concrete proposals. Legal and political considerations surface in assessing the existence of this paradox, and despite the lack of a consistent political will, to implement the decisions of ECOWAS Court relevant judicial actors have roles to play. National courts could take a bolder approach in complementing the work of the ECOWAS Court. The ECOWAS Court itself could put in place concrete mechanisms and adopt certain practices to address this poor record of non-implementation. It is yet to be seen how substantive mechanisms would work in practice.


2019 ◽  
Vol 13 (1-2) ◽  
pp. 95-115
Author(s):  
Brandon Plewe

Historical place databases can be an invaluable tool for capturing the rich meaning of past places. However, this richness presents obstacles to success: the daunting need to simultaneously represent complex information such as temporal change, uncertainty, relationships, and thorough sourcing has been an obstacle to historical GIS in the past. The Qualified Assertion Model developed in this paper can represent a variety of historical complexities using a single, simple, flexible data model based on a) documenting assertions of the past world rather than claiming to know the exact truth, and b) qualifying the scope, provenance, quality, and syntactics of those assertions. This model was successfully implemented in a production-strength historical gazetteer of religious congregations, demonstrating its effectiveness and some challenges.


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