Ecosystems In Countries Research Articles

Operationalising relational theory of entrepreneurial ecosystems at city-level in Africa, Asia and the Middle East

Abstract Relational theory has been a key advancement in understanding how entrepreneurial ecosystems work. However, the theory has not yet been operationalised through measurement methodologies. This study proposes an indicator-based framework and composite index methodology which builds on relational ecosystem theory. Starting from the premise that common aggregation methods like the arithmetic mean fail to convey the interdependence of ecosystem components (such as complementarity vs. substitution), this study explores the potential of geometric mean as an alternative approach. Our analysis shows that geometric mean methods render more plausible results than simple arithmetic mean; they operationalise complementarity between components more directly by introducing heftier penalties for imbalances in the ecosystem. Additionally, our methodology identifies the less-explored city-level as the most meaningful unit of analysis of entrepreneurial ecosystems. To test the index, we use a unique set of quantitative data for eleven middle-income cities, namely Accra, Amman, Bangkok, Beirut, Bengaluru, Cairo, Jakarta, Manila, Nairobi, Rabat, and Tunis. As most previously conducted measurements have targeted either mature or country ecosystems, our goal is not limited to methodological advancements in measuring entrepreneurial ecosystems, but it also relates to expanding the current status of research to less explored world regions.

Carbon Consumption, the Carbon-Based Ecosystem, and Output

This paper studies the effects of the carbon-based ecosystem on a country's output. We propose and estimate a dynamic game production model in which a country's ecosystem, as measured by its reservoir of carbon in land biomass and soils, is a productive input. This reservoir is diminished when higher levels of greenhouse gas concentrations reduce land sink absorption of atmospheric carbon. In equilibrium, a country's land carbon policy accounts for its direct effects on the ecosystem and on diminished land sink as GHG concentrations increase. We first estimate land sink absorption rates and the output elasticities of land use and the land carbon ecosystem for 152 countries. Calibrating the model to these estimates, we simulate the model to 2100 under four standard Representative Concentration Pathway scenarios. In the simulations, all countries experience higher average annual GDP growth under lower GHG concentration scenarios. The growth differentials between high and low scenarios are starkest for more developed countries. When compared to a counterfactual constant sink model, the ``active sink makes little difference in low concentration scenarios, but decreases global GDP growth by around 1.3% per year over the next 80 years in the highest scenario. Again, the differences are most pronounced in developed countries.

A Spatio-Temporal Autowave Model of Shanghai Territory Development

A spatio-temporal model of megacity development that treats the megacity as an active medium is presented. From our point of view, it is advisable to consider the process of urban ecosystem development from the standpoint of the theory of autowave self-organization in active media. According to this concept, the urban ecosystem is considered as interacting with each other’s natural and anthropogenic subsystems with significant heterogeneity of areas affected by human intervention and urban geobiocoenoses. The model is based on the general principles of active medium dynamics; therefore, it is universal for any object to be considered an active medium. The only difference when using the model to predict the development of urban ecosystems in countries with different socio-economic and political prerequisites is the variety of parameters included in the model, i.e., the activation parameter, the autowave process inhibitors, and the characteristic scales of the activator and inhibitor. The model was tested on the example of Moscow expansion in the period of 1952–1968 and showed good agreement with the map data. By means of the model, a prediction of Shanghai and surrounding territory development until 2030 was made.

Resource recovery from sanitation to enhance ecosystem services

Sanitation is often viewed as an unmentionable social obligation. Efficiently delivering this public good may involve use of ecosystem services, such as pollutant assimilation in wetlands, yet sanitation need not only consume: recovered resources (nutrients, organic matter and water) may enhance multiple ecosystem services, thereby expanding the value of sanitation. However, potential linkages between sanitation and ecosystem services have received limited attention. Bridging these fields will reveal opportunities to support sustainability goals, particularly in settings with extensive ecological assets but limited economic means. Here we develop a conceptual framework defining pathways through which recoverable resources can enhance ecosystem services and shed light on the viability of exploring synergistic interactions between engineered and natural systems. We find underexplored potential, particularly relating to the contribution resource recovery could make to regional ecosystems in countries across the globe. Such integrative work is needed to advance knowledge of sanitation–ecosystem linkages and stimulate policy efforts to enhance sustainable development and resource cycles. Sanitation is usually considered just an engineering and public health issue. This Perspective suggests avenues by which recoverable resources can enhance ecosystem services, such as provisioning nutrients for food production, and suggests synergies that can promote sustainable development.

Waste valorisation opportunities for bush encroacher biomass in savannah ecosystems: A comparative case analysis of Botswana and Namibia

Bush encroachment of savannah ecosystems in countries like Botswana and Namibia has been identified as a major problem threatening biodiversity, grazing land productivity and the generation of groundwater. Incidentally, the same problem presents a huge biomass energy resource opportunity which can be exploited through various technologies. This paper defines the scope of the problem in Botswana, comparing with the well documented and partly proven case of encroacher bush waste valorisation in Namibia. This biomass is therefore a large homogeneous sustainable waste resource base that is perennially available, due to the drought-hardiness of the encroachers. It is however, necessary to conduct preliminary studies to explore prospects and possibilities, benchmarking with globally renowned biomass experts like Germany and the United Kingdom. The study shows that the issue of bush encroachment in Botswana has been documented from as far back as 1971, though earlier studies were mostly evaluations from a natural resources perspective which did not proffer solutions. Besides a project by United Nations Development Programme to try and benchmark from Namibia’s biomass to charcoal initiatives from their encroacher bushes, there is no documented effort by Botswana to derive value out of the vast resource which has invaded thousands of hectares of rangelands. Meanwhile, Namibia has recorded significant success in converting the encroacher bushes into wood chips for use in boilers (heat production) for a cement plant, charcoal for domestic and commercial heating/cooking and briquettes for power generation. Feasibility studies have been made for the possibility of scaling up these projects, while exploring other existing and emerging sustainable technologies like pelletizing, gasification, pyrolysis and engineered wood products. Essentially, a review of the existing problem in Botswana, experiences for various cases and recommendations by experts make this compilation valuable for the nation and other regions experiencing the same problem.

Interspecific hybridization between Bursaphelenchus xylophilus and Bursaphelenchus mucronatus

Bursaphelenchus xylophilus is the pathogen that causes pine wilt disease, which has greatly damaged forests and ecosystems in countries of East Asia and Europe. Bursaphelenchus mucronatus is closely related to B. xylophilus in morphology and host plant specificity. A long-running debate has existed regarding whether these two species can successfully produce hybrid offspring. In the present study, we performed in the laboratory, hybridization of two B. xylophilus nematode isolates from China and Japan and three B. mucronatus isolates from China, Japan and France. Nematode isolates of B. xylophilus were successfully crossed with B. mucronatus isolates, and the rate of hybridization was relatively high; however, some hybrid offspring died. Successful hybridization occurred between B. xylophilus and B. mucronatus isolates from China, and 22 generations of hybrids were produced. All F1 hybrids could be backcrossed with their parents and produce offspring. Variation in mucro length among the hybrid offspring and their parents was observed. The hybrid offspring and their parents were inoculated into 3-months-old black pine (Pinus tunbergii) seedlings. Weaker pathogenicity of hybrid offspring was observed compared with that of their parents, and significantly fewer offspring nematodes than parents were reisolated from pines. Therefore, the offspring of B. xylophilus and B. mucronatus may exist in the forest and could influence disease epidemics.

Managing mangroves for coastal ecosystems change: A decade and beyond of conservation experiences and lessons for and from west-central Africa

Unsustainable human activities and climate change are threatening the sustainability of coastal ecosystems in countries of West-Central Africa. This paper advocates that focusing on mangrove ecosystem management can potentially mitigate these threats by pointing out clues on management orientations and opportunities for other coastal systems. This article elucidates this point by using evidence from informal interviews with stakeholders and expert-led literature reviews to assess mangrove conservation interventions implemented between 2000 and 2014 across countries of West Africa and Cameroon. Results show that many institutions are taking actions in countries of West Africa and Cameroon to conserve and restore mangroves. These interventions may be slowing down the rate of mangrove forest loss across West-Central Africa. However, this recovery does not appear to be benefiting other coastal ecosystems. This unequal distribution may be linked to the increasing challenges plaguing coastal ecosystems management, and hence the effectiveness of mangrove conservation efforts in this region. These problems are both internal and external to institutions, undertaking targeted interventions. External challenges are beyond the control of implementing organizations and synergize with internal institutional deficiencies to impede overall coastal ecosystem sustainability. Improving overall coastal ecosystems sustainability in this region will, therefore, require a coordinated approach between all stakeholders that are directly or indirectly influencing coastal ecosystems. In this regard, practitioners need to improve the effectiveness of traditional conservation practices, expand conservation efforts and funding mechanisms as well as develop integrated strategies that encompass all activities that affect coastal ecosystems, in a vertical and horizontal manner. Key words: Mangroves, coastal ecosystems, conservation effort, conservation challenges, ecosystem services.

Seed-mediated gene flow promotes genetic diversity of weedy rice within populations: implications for weed management.

Increased infestation of weedy rice—a noxious agricultural pest has caused significant reduction of grain yield of cultivated rice (Oryza sativa) worldwide. Knowledge on genetic diversity and structure of weedy rice populations will facilitate the design of effective methods to control this weed by tracing its origins and dispersal patterns in a given region. To generate such knowledge, we studied genetic diversity and structure of 21 weedy rice populations from Sri Lanka based on 23 selected microsatellite (SSR) loci. Results indicated an exceptionally high level of within-population genetic diversity (He = 0.62) and limited among-population differentiation (Fst = 0.17) for this predominantly self-pollinating weed. UPGMA analysis showed a loose genetic affinity of the weedy rice populations in relation to their geographical locations, and no obvious genetic structure among populations across the country. This phenomenon was associated with the considerable amount of gene flow between populations. Limited admixture from STRUCTURE analyses suggested a very low level of hybridization (pollen-mediated gene flow) between populations. The abundant within-population genetic diversity coupled with limited population genetic structure and differentiation is likely caused by the considerable seed-mediated gene flow of weedy rice along with the long-distance exchange of farmer-saved rice seeds between weedy-rice contaminated regions in Sri Lanka. In addition to other effective weed management strategies, promoting the application of certified rice seeds with no weedy rice contamination should be the immediate action to significantly reduce the proliferation and infestation of this weed in rice ecosystems in countries with similar rice farming styles as in Sri Lanka.

Historical biogeography of the predominantly Australian plant family Goodeniaceae

AbstractAimThe plant family Goodeniaceae includes 12 genera, largely restricted to Australia. They are a diverse and conspicuous element of the country's ecosystems and an important clade to consider in the effort to reconstruct the historical biogeography of this continent. We used a time‐calibrated molecular phylogeny to perform ancestral‐area reconstructions for the family, in order to: (1) determine its area of origin; (2) test whether vicariance played a role in the history of lineages occupying the south‐western and south‐eastern regions; (3) trace diversification processes in the central arid zone; and (4) trace potential eastward dispersals into the Pacific.LocationAustralia and the Pacific.MethodsWe employed a previously published molecular dataset to develop a time‐calibrated phylogeny for the Goodeniaceae using beast 1.6.1 with both primary and secondary node calibrations. Ancestral areas were reconstructed via both dispersal–extinction–cladogenesis (DEC) and statistical dispersal–vicariance analysis (S‐DIVA).ResultsThe Goodeniaceae split from Asteraceae + Calyceraceae c. 78 Ma, with the divergence of the Lechenaultia, Anthotium and Dampiera (LAD) clade from the remainder of the family c. 67 Ma. Although the geographical origin of the family is equivocal, the LAD clade originated in south‐western Australia, and the remainder of the family, especially Goodenia s.l., probably originated in the central Eremaean zone. The majority of Goodenia cladogenesis events occurred during the Miocene, with expansions to the north, south‐east and south‐west. The crown radiation of Scaevola s.l. occurred later, during the second half of the Miocene, and has involved several recent extra‐Australian dispersals into the Pacific.Main conclusionsAlthough it is unclear where in Australia the family originated, our results support a south‐western origin for the LAD clade and considerable diversification of some clades within Goodenia s.l. and Scaevola s.l. in that zone. A relative paucity of mid‐Miocene sister relationships between south‐western and south‐eastern lineages suggests that the occupants of these regions were not affected by contemporary vicariance events. Instead, our results suggest that the aridifying Eremaean zone was an important source and sink for lineages, especially in Goodenia s.l. Dispersal is inferred for the extra‐Australian lineages due to their recent origins.