Spatial Competition Research Articles

The Effects of Infectious Diseases on the Consequences of Interspecific Competition in Grassland Communities

As infectious diseases have a severe impact on the individual survival and competitive ability of host species in grassland communities, competition between relevant species may have different consequences, potentially influencing the species composition of grassland communities and the functioning of grassland ecosystems. Understanding the impact of infectious diseases on competition is thus crucial for the health management of grassland ecosystems. How do infectious diseases affect the competitive coexistence of grassland plant species? In this study, by drawing on Tilman’s multispecies competition model and incorporating the spread characteristics of grassland plant diseases, we built three spatial competition models of two grass species subject to infectious diseases, and we analyzed the invasion conditions of infectious diseases and how they impact the population dynamics and competitive consequences of the species. Our model revealed the following: (1) Diseases with high transmission rates and low virulence are more likely to invade populations, while the presence of non-host species is detrimental to disease invasion. (2) Disease promotes the coexistence of competing species, breaking down the original competition–compromise trade-off mechanism for species coexistence and greatly expanding the range of parameters within which the two species can coexist. (3) Pathogen infections indirectly weaken the suppression of inferior species by dominant species, which is similar to the cascade effect seen in trophic interactions. Our findings highlight the importance of disease in species coexistence and grassland biodiversity maintenance.

Competition effects can mislead selection in eucalypt breeding trials

The assessment of plant performance and the accuracy of genetic selection can be significantly affected by genetic competition among individuals. In addition to genetic causes, competition is influenced by external factors such as environment and age. This research uses multi-location multi-age Eucalyptus dunii trials to answer four questions: i) Are there major changes when competition effects (both genetic and residual) are estimated in single-age and multi-age models? ii) What are the implications of considering competition effects on the early selection of eucalypt clones? iii) What are the impacts of considering the reliability of direct (DGE) and indirect genotypic effects (IGE) as a weight in a selection index?, and iv) Which clones hold the potential to form highly productive clonal plantations in Southern Brazil when deployed together as clonal composites? The dataset contained three trials established in different locations in Southern Brazil, where growth traits were measured at 3.5 and 7 years. We fitted single-age and multi-age spatial competition models for each trial. The multi-age spatial competition model was a valuable tool for selecting superior eucalypt clones. Neglecting the IGEs led to changes in clone ranking, reducing the effectiveness of early selection. Additionally, a selection index where DGEs and IGEs are weighted by their reliability was proposed. Therefore, our study contributes to understanding the magnitude of IGE's impact on the daily practice of eucalypt breeding, such as early selection and multi-age analyses, and proposes selection strategies that consider the quantity and quality of information provided by the models for each individual.

Provincial income convergence in Vietnam: spatio-temporal dynamics and conditioning factors

In this article, we use a three-step procedure that combines the log t convergence test, Explanatory Spatial Data Analysis, and ordered logit regression to determine the spatio-temporal dynamics and determinants of provincial income clustering in Vietnam during the 2010–2020 period. Our findings are three-fold. First, provincial income clustering in Vietnam follows patterns of club convergence towards multiple equilibria. Seven convergence clubs encompassing 61 provinces are identified. Second, spatial autocorrelation encourages neighboring provinces to converge toward shared income equilibria. High-income clusters are observed in the Northern and Southern Key Economic Regions, while low-income clusters are concentrated in the mountainous areas of Northern Vietnam. Finally, both internal and external factors significantly affect the formation of convergence clubs. Vital internal factors include localities’ initial conditions of physical capital and structural change. Meanwhile, external factors refer to spatial externalities among neighboring provinces. We highlight spatial complementarity in physical capital accumulation and spatial competition in industrial intensification among neighboring provinces.

Optimization of land use to accommodate nutritional transformation of food systems: a case study from the Beijing–Tianjin–Hebei region

The transformation and reconstruction of China’s food system not only faces many risks, such as the unceasing growth of food consumption on the demand side and the structural imbalance of dietary nutrition, but also must address serious challenges, such as constraints of resources, environment, and production capacity on the supply side. The optimal allocation of land use structure is an important method to realizing a transformation of sustainable food systems, achieving the goal of nutrition security, and guiding coordinated spatial development. This study takes the Beijing–Tianjin–Hebei region as an example, analyzing the development trends of the region’s dietary nutrition structure clarifies the objectives for improving dietary nutrition. This study uses comprehensive optimization model and dynamic land system model, exploring land use optimization schemes under different nutritional goals and development scenarios. The result show that the dietary structure in the Beijing–Tianjin–Hebei region is transitioning from “food based” to “intake balance” and gradually evolved to “intake diversity,” with the main objectives being to maintain stable calorie intake while moderately increasing protein intake and reducing fat intake. Achieving this goal will gradually increase demand for cultivated land and intensify spatial competition for land use. However, by optimizing land use allocation, it is possible to free up more spatial resources to balance economic development and ecological protection and reduce land use fragmentation, thereby significantly enhancing regional economic benefits and the value of ecosystem services based on improvements in dietary nutrition.

Let's (re)locate digitally: spatial competition for users' engagement in the social media space

Let's (re)locate digitally: spatial competition for users' engagement in the social media space

Sharing or sparing? The trade-offs among urban services, food production and ecosystem services

As urbanization continues to spread rapidly, the competition for space among urban, agricultural, and natural land uses is becoming increasingly fierce. The urgent question is how to harness the advantages of urbanization while mitigating its potentially harmful consequences. This research extends analytical framework of land sharing and sparing to urban land use and provides a comparable quantification approach to determine the comprehensive impact of urban services, food production, and ecosystem services. The results show that the overall value loss of the land sparing scenario is 23.6% lower than that of the sharing scenario on average, and the Eco-sparing scenario exhibits the smallest loss, which is only 55.4% of that under the Urb-sharing scenario. While land-sparing strategies mitigate the loss of local food production and ecosystem services, fostering a potentially mutually beneficial outcome, they also elevate the cost of accessing urban services. This creates a delicate trade-off between urban services and food production/ecosystem services, ultimately posing challenges in achieving an optimal win-win situation. The key contribution of this paper lies in extending the land sharing and sparing framework to urban areas, agricultural land, and ecosystems. It also introduces methods to quantitatively assess trade-offs among these land uses. This extended framework for land use offers insights into spatial competition due to urbanization and provides decision-making analysis tools for land use and planning.

Compete or Avoid? Assessing Brand Competition Strategies with Spatial Colocation Analysis

Spatial competition considerations are important in hotel location selection. This study proposes and demonstrates a method of colocation network analysis to quantify the potential encroaching effect of spatial inter- and intra-competition between units of business brands that seek expansion. The environmental context of the study is a network of the top five budget hotel brands in the Beijing hotel market. The results reveal that brands implement different strategies in their hotel placement, which are subject to different levels of the encroaching effect. However, the method is applicable in a variety of hospitality settings, specifically in those that involve the development strategies of chain brands. The simulation capability of the method can assist hospitality brands in assessing the outcomes of a proposed development and, thus, aid hoteliers in the spatial allocation of new units with the least adverse effects on their existing business networks.

Ecological determinants of spotted hyena Crocuta crocuta occupancy in Comoé National Park, Côte d’Ivoire

Knowledge of the large carnivore guild is important in view of a possible lion reintroduction into the Comoé National Park (CNP), northern Côte d’Ivoire. We used camera trapping to assess activity patterns, habitat selection, and ecological factors influencing the occupancy of the spotted hyena Crocuta crocuta. Our results showed that the presence of leopard Panthera pardus, the only current other large carnivore and thus potential competitor, did not influence hyena occupancy. Hyena occupancy was only significantly related to Euclidian distance to nearest water point. Manly’s alpha habitat selection index values show a preference of spotted hyena for shrub savannah (αSa = 0.71), and Pianka’s overlap index showed low spatial competition with leopard (OIJ(PNC) = 0.12). Our findings showed that spotted hyena were mostly nocturnal, and generally active at the same time slots with leopard, leading to a high index of temporal overlap (OIJ(time) = 0.78). The kernel density estimation confirmed that spotted hyenas and leopard shared almost half of their activity patterns (Δ1 = 0.49 and 95% CI = 0.26–0.71). Prey diversity is high in CNP but anthropogenic threats appear to suppress population growth of prey and predators. Conservation efforts should continue to reduce pressures before contemplating a potential lion Panthera leo reintroduction.

Maintaining carbon in the forest soils of the Morvan (France): spatial and knowledge competition around the evolution of practices

Maintaining carbon in the forest soils of the Morvan (France): spatial and knowledge competition around the evolution of practices

Metagenome-assembled genomes of three Hepatoplasmataceae provide insights into isopod-mollicute symbiosis.

The digestive organs of terrestrial isopods harbour bacteria of the recently proposed mollicute family Hepatoplasmataceae. The only complete genome available so far for Hepatoplasmataceae is that of 'Candidatus Hepatoplasma crinochetorum'. The scarcity of genome sequences has hampered our understanding of the symbiotic relationship between isopods and mollicutes. Here, we present four complete metagenome-assembled genomes (MAGs) of uncultured Hepatoplasmataceae members identified from shotgun sequencing data of isopods. We propose genomospecies names for three MAGs that show substantial sequence divergence from any previously known Hepatoplamsataceae members: 'Candidatus Tyloplasma litorale' identified from the semiterrestrial isopod Tylos granuliferus, 'Candidatus Hepatoplasma vulgare' identified from the common pill bug Armadillidium vulgare, and 'Candidatus Hepatoplasma scabrum' identified from the common rough woodlouse Porcellio scaber. Phylogenomic analysis of 155 mollicutes confirmed that Hepatoplasmataceae is a sister clade of Metamycoplasmataceae in the order Mycoplasmoidales. The 16S ribosomal RNA gene sequences and phylogenomic analysis showed that 'Candidatus Tyloplasma litorale' and other semiterrestrial isopod-associated mollicutes represent the placeholder genus 'g_Bg2' in the r214 release of the Genome Taxonomy Database, warranting their assignment to a novel genus. Our analysis also revealed that Hepatoplasmataceae lack major metabolic pathways but has a likely intact type IIA CRISPR-Cas9 machinery. Although the localization of the Hepatoplasmatacae members have not been verified microscopically in this study, these genomic characteristics are compatible with the idea that these mollicutes have an ectosymbiotic lifestyle with high nutritional dependence on their host, as has been demonstrated for other members of the family. We could not find evidence that Hepatoplasmataceae encode polysaccharide-degrading enzymes that aid host digestion. If they are to provide nutritional benefits, it may be through extra-copy nucleases, peptidases, and a patatin-like lipase. Exploration of potential host-symbiont interaction-associated genes revealed large, repetitive open reading frames harbouring beta-sandwich domains, possibly involved with host cell adhesion. Overall, genomic analyses suggest that isopod-mollicute symbiosis is not characterized by carbohydrate degradation, and we speculate on their potential role as defensive symbionts through spatial competition with pathogens to prevent infection.

Root spatial distribution and belowground competition in an apple/ryegrass agroforestry system

CONTEXTForestry and fruit industry is a unique and advantageous industry in Xinjiang, China, and it is an important channel for farmers to increase income. With limited land resources and a shortage of forage in southern Xinjiang, farmers began to establish a fruit-grass interplanting model to improve the comprehensive economic benefits of orchards. OBJECTIVEThe objective of this study was to explore the effects of apple/ryegrass intercropping system on root spatial distribution and competition, and to evaluate the performance of field microclimate, soil physical properties and productivity under intercropping. METHODSIn the study, three different planting patterns were designed: sole-cropped apple (The spacing of the rows of apple trees was 4.0 m, and the plant spacing was 1.0 m), sole-cropped ryegrass (Strip sowing, row spacing was 0.25 m), and apple/ryegrass intercropping (The distance from apple row to ryegrass row was 1.0 m). Two-year field experiments were conducted to measure the root length density (RLD), specific root length (SRL), interspecific competitiveness index, soil moisture content, organic matter content, air temperature, relative humidity, wind speed, yield, land equivalent ratio (LER) and aggressivity. RESULTS AND CONCLUSIONCompared with sole cropping, intercropping reduced the RLD of apple and ryegrass and increased the SRL of ryegrass. The competition space between apple and ryegrass was concentrated in the soil area of 100 cm horizontally and 0–20 cm vertically, and apple was more competitive than ryegrass. Intercropping increased the content of soil moisture and organic matter and improved the microclimate of farmland, decreased the air temperature, increased the relative humidity of an orchard, and decreased wind speed. Although intercropping reduced ryegrass and apple yield, land equivalent ratio (LER) was 1.27–1.30, indicating that intercropping improved land use efficiency. Root competition led to an uneven distribution of root length density (RLD) and specific root length (SRL). The plasticity of root morphology and root spatial distribution was key to adapting to competition and maximizing the absorption of water and nutrients in apple/ryegrass agroforestry systems. SIGNIFICANCEApple/ryegrass intercropping system maximizes resource utilization and reduces interspecies resource competition. It improved land use efficiency, improved the comprehensive benefits of fruit and grass production.

Spatial Competition and Unevenness in Global Capitalism: Labor, Nature, and the Seesaw of Capital

Critical studies of globalization seek to unmask how this stage of capitalist history reshapes patterns of uneven development around the world. While globalization can reproduce long-standing patterns of North–South unequal exchange, in this paper, I focus on how capital mobility and competition contribute to uneven development. Drawing primarily on Neil Smith’s theory of uneven development, I offer a theoretical discussion of how capital’s capacity to seesaw from place to place in its search for higher profits—and the spatial competition between places that this capacity triggers—constitutes a source of unevenness. Regions, nations, and localities adapt to capital’s seesaw by offering, among others, cheaper labor and lower environmental regulation costs. While this can work for a time, advantages are either eroded by the unfolding contradictions of capitalism or competed away by the emergence of new areas. In the last section, I offer a tentative illustration of this argument with a brief examination of pollution havens and Special Economic Zones.

New horizons in light control of plant photomorphogenesis and development

Light from Sun has tremendously shaped the evolution of plants and represents one of their key triggers for proper morphogenesis and development. Energy from Sun light is converted by photosynthesis into chemical energy that ultimately drives all energy consuming processes in plants. Besides, Sun light provides information about environmental conditions or constraints and signals important parameters such as day length, time point of season, direction and intensity of illumination or spatial competition with neighbouring plants. Plants possess a sophisticated array of photoreceptors that perceive this information (photoperception) and initiate signalling pathways that control appropriate responses at developmental or physiological level. While the primary processes of photoperception are largely understood, many aspects of the subsequent signalling networks are still elusive and especially the interaction with other signalling networks is far from understood. Light represents also a highly versatile tool for scientists to study morphogenesis and development of plants by a steadily increasing number of remote sensing technologies that allow to observe plants in real time and high resolution (photodetection). Further, scientists now can even use the knowledge about photobiology and photoreceptors to construct synthetic tools that can be genetically introduced into plants to monitor internal processes (so-called biosensors). Recent technological developments in optogenetics even allow to generate tools that actively regulate gene expression or metabolism by selective illumination (photocontrol). In this perspective article we highlight progress in our understanding of light signalling and a number of selected technological improvements in photocontrol with a special focus on the areas of phytochrome signalling and plant optogenetics.

Herbivorous Reef Fish Interaction with the Habitat and Physicochemical Variables in Coral Ecosystems in the Mexican Tropical Pacific

Herbivorous fish can mediate spatial competition between algae and corals, which is crucial for coral ecosystems. However, in areas with limited coral coverage like the Mexican tropical Pacific (MTP), this dynamic is not fully understood. This study, using a functional trait approach and ordination analysis, explores whether herbivorous reef fish assemblage influences the benthic habitat components or if physicochemical factors define the habitat variability in the MTP’s Cleofas and Marietas insular systems. We analyzed if this relationship persisted across systems and over time, and identified species traits tied to habitat variability. Island comparison analyses between Cleofas and Marietas reveal that both herbivorous reef fish and physicochemical variables shape the habitat. Cleofas had larger mobile herbivorous fish that formed groups related mostly to macroalgae cover. In contrast, temporal analysis of Marietas shows that the habitat is primarily shaped by physicochemical variables with herbivorous fish being mainly small farmer species related to branching corals. Notably, these closely situated insular systems present varied ecosystem mediators, influenced by diverse drivers including fish traits and environmental factors. This study underscores the potential of employing a framework of ecological species traits combined with ordination methods to unravel the distinct site dynamics that contribute to the persistence of coral ecosystems within the MTP.

Spatial Competition, Strategic Entry Responses, and the North Dakota Railroad War of 1905

Spatial Competition, Strategic Entry Responses, and the North Dakota Railroad War of 1905

Spatial Competition, Strategic Entry Responses, and the North Dakota Railroad War of 1905

Spatial Competition, Strategic Entry Responses, and the North Dakota Railroad War of 1905

Spatial Competition in Fast-Charging Networks

Spatial Competition in Fast-Charging Networks

Spatial Competition and Pass-through of Fuel Taxes – Evidence from a Quasi-natural Experiment in Germany

Spatial Competition and Pass-through of Fuel Taxes – Evidence from a Quasi-natural Experiment in Germany

The Effect of Spatial Competition on Retail Gasoline Prices

This paper explores the nature of retail gasoline market competition in the Russian Federation by applying a detailed panel structure database at the level of individual filling stations. This market is a highly concentrated one, which theoretically enables companies to exercise market power. Furthermore, in most of the administrative districts of the Russian Federation, one vertically integrated oil company will dominate; this is often the company located nearest to its own refinery. Spatial econometric analysis has yielded some interesting empirical results concerning how the local market is affected. First, there is no confirmation of the hypothesis that gas stations compete only with the nearest gas stations. Second, there is strong evidence that stations compete with other filling stations located within five kilometers, and the intensity of competition decreases as the distance between stations increases. A relationship between certain characteristics of filling stations and the price behavior of individual filling stations also became evident. These results suggest that retail fuel prices are influenced by such features of filling stations as brand name and services provided. The conclusion is that the brand name of competing stations and even the geographical distribution of these specific brands are more important determinants of the retail price of gasoline than the number of competing stations.

INNOVATION, COOPETITION AND SPILLOVER EFFECTS IN EUROPEAN REGIONS

Innovation and investment are critical to economic growth. In this article, we address the complex task of evaluating the capacity of regional innovation to increase investment and generate spillovers in regions of the European Union (EU) from both spatial and temporal perspectives. Using panel data estimation methods and exploring the effects of dynamic spatial autocorrelation, our findings show a positive spatial autocorrelation at the level of EU regions. We also observed spatial competition, both in terms of the distribution of investments and in terms of the diffusion of short-term innovation gains. We argue that, in the short term, EU regions tend to behave as competitors for investment fixing, but in the long run, innovation has the potential to generate spillover effects on neighbouring regions. Furthermore, we find that investment patterns were characterized by a significant temporal autocorrelation, showing that shocks to investment in regions tend to be absorbed in a few periods. This paper attempts to fill existing gaps by using estimation methods for dynamic spatial panel data to identify and explore the effects of regional innovation on investment for the 154 European Union regions, and reports original findings as regards the knowledge spillover across European regions.