Changes In Population Density Research Articles

Exploring the Relationship between Temporal Fluctuations in Satellite Nightlight Imagery and Human Mobility across Africa

Mobile phone data have been increasingly used over the past decade or more as a pretty reliable indicator of human mobility to measure population movements and the associated changes in terms of population presence and density at multiple spatial and temporal scales. However, given the fact mobile phone data are not available everywhere and are generally difficult to access and share, mostly because of commercial restrictions and privacy concerns, more readily available data with global coverage, such as night-time light (NTL) imagery, have been alternatively used as a proxy for population density changes due to population movements. This study further explores the potential to use NTL brightness as a short-term mobility metric by analysing the relationship between NTL and smartphone-based Google Aggregated Mobility Research Dataset (GAMRD) data across twelve African countries over two periods: 2018–2019 and 2020. The data were stratified by a measure of the degree of urbanisation, whereby the administrative units of each country were assigned to one of eight classes ranging from low-density rural to high-density urban. Results from the correlation analysis, between the NTL Sum of Lights (SoL) radiance values and three different GAMRD-based flow metrics calculated at the administrative unit level, showed significant differences in NTL-GAMRD correlation values across the eight rural/urban classes. The highest correlations were typically found in predominantly rural areas, suggesting that the use of NTL data as a mobility metric may be less reliable in predominantly urban settings. This is likely due to the brightness saturation and higher brightness stability within the latter, showing less of an effect than in rural or peri-urban areas of changes in brightness due to people leaving or arriving. Human mobility in 2020 (during COVID-19-related restrictions) was observed to be significantly different than in 2018–2019, resulting in a reduced NTL-GAMRD correlation strength, especially in urban settings, most probably because of the monthly NTL SoL radiance values remaining relatively similar in 2018–2019 and 2020 and the human mobility, especially in urban settings, significantly decreasing in 2020 with respect to the previous considered period. The use of NTL data on its own to assess monthly mobility and the associated fluctuations in population density was therefore shown to be promising in rural and peri-urban areas but problematic in urban settings.

Sustainable land use scenarios generated by optimizing ecosystem distribution based on temporal and spatial patterns of ecosystem services in the southern China hilly region

Urban expansion and inappropriate land uses in the southern China hilly region have caused a decline in the regional ecosystem services capacity. The exploration of regional ecosystem services under the principle of protecting and improving ecological functions is essential for optimizing land use. Therefore, we determined the ecosystem service value (ESV) in the southern China hilly region from 2000 to 2020 and attempted to analyse the drivers that caused these changes. The ESV decreased from 2000 to 2005 and then increased from 2005 to 2020, with the changes being correlated with changes in regional precipitation, temperature, GDP, and population density. We optimized the land use in 2035 based on these results and conducted simulation experiments to optimize the spatial pattern in three future scenarios: business as usual scenario (BUS), coordinated development scenario (CDS), and ecological priority scenario (EPS). The highest ESV was achieved in the EPS, followed by the CDS, and the lowest ESV was in the BUS. An optimized CDS was regarded as the most feasible approach for the future because it could effectively balance the synergistic relationships between social and ecological factors. The results are a practical scientific resource for future planning and the study provides a feasible method for the implementation of a national ecological protection strategy in the southern China hilly region.

Influence of the natural radon radiation on the spread of the COVID 19 pandemic

The statistics of COVID-19 accumulated in Ukraine show areas with a significantly lower incidence of diseases. The purpose of the study was to identify factors that could influence the pattern of the pandemic in a particular area. Within the study it was assumed that the level of health care is approximately the same throughout the country. Population density was considered the main factor influencing the dynamics of the spread of infection. To reduce the impact of changes in population density across regions, it was normalized by the average population density in the country. The normalization of statistics for the country resulted in a model in the form of a linear relationship between the normalized values of the number of COVID-19 cases in the region and the size of the region. Subsequent analysis of the graphical data made it possible to identify four regions with the lowest incidence of COVID-19. The geographical proximity of these regions Dnipro, Kherson, Vinnytsia and Kirovograd, indicates the presence of a common factor for them, not typical for the rest of Ukraine. Such a factor may be the location of 83% of Ukraine's uranium deposits in the territories around Kirovohrad. Radon is one of the decay products of uranium, so the population of these areas may experience increased exposure to radon. This noble gas has more than a century of medical use, in particular for pulmonary diseases, although there is still no consensus about its effectiveness and side effects. Considering that COVID-19 was often complicated by pulmonary diseases, it can be assumed that the geological specificity of these four regions of Ukraine had an impact on the course of the COVID-19 pandemic in their territories. The study findings are important in terms of further COVID-19 research and prevention strategies.

Spatiotemporal evolution and relationship between construction land expansion and territorial space conflicts at the county level in Jiangsu Province

In rapidly urbanizing areas, intense human development activities and fierce competition for spatial resources have led to apparent territorial space conflicts. This paper selects Jiangsu Province as the study area to explore the spatiotemporal evolution characteristics and response relationship between the expansion of county-level construction land and territorial space conflicts from 1985 to 2020 to provide a reference for regional territorial space optimization. The results show that the construction land expansion intensity (CEI) at the county level showed a spatial characteristic of greater power in the southeast than in the northwest. The spatial expansion mode (SEI) was mainly characterized by spread type, with construction land experiencing marginal expansion, the emergence of new independent expansion points, and then the expansion process of agglomeration distribution. From 1985 to 2020, there was a significant increase in territorial space conflicts and an increase in spatial aggregation at the county level. The regions with high space conflicts intensity index (SCII) values and high increase in space conflicts intensity changes (SCIIC) were mainly located in Xuzhou, Nanjing, and at the junction of Changzhou, Wuxi, Suzhou, and Zhenjiang. There was a positive correlation between CEI and SCIIC, and the correlation of positive correlation units increased from south to north. There was a positive correlation between SEI and SCIIC, and the units with a strong positive correlation were mainly located in Xuzhou, Nantong, Changzhou, and Wuxi. The changes in population density and GDP also affect SCIIC. This paper strengthens the understanding of the spatiotemporal evolution characteristics and related relationships of construction land expansion and territorial space conflicts at the county level over a long time, which can provide a decision-making basis and reference for the regulation of county construction land expansion, territorial space optimization in Jiangsu Province.

Applications of evolutionary game theory in urban road transport network: A state of the art review

A sustainable transport infrastructure is one of the pillars of a sustainable city. However, the literature indicates that urbanization, population growth, changes in population density, and motorization make it difficult for the current road transport system to meet mobility needs for a sustainable city. Traffic crashes and congestion on roads are common as a result of increasing travel times, fuel consumption, and carbon emissions, thereby reducing efficiency and sustainability of mobility systems. Managing these issues involves the interaction of multiple decision-makers, such as vehicles, pedestrians, traffic system operators, and authorities. Accordingly, these are well-suited to being analyzed under the guise of game theory. While classical game theory possesses multiple limitations, it can be argued that evolutionary game theory (EGT) models are more effective for real-world scenarios. This manuscript presents a state-of-the-art review on EGT applied to the road transportation network. The manuscript has divided the application of EGT in advancing the transportation network into multiple categories, i.e., choice-based analysis, traffic management, behavioral interactions, routing operation, and transport safety. This manuscript provides an in-depth analysis and a comparative criticism of the various proposed evolutionary game models. Finally, the manuscript discusses the challenges and provides recommendations for future research on evolutionary game models in transportation networks. These insights aim to facilitate targeted activities based on current research needs.

Repeated long-term population growth overshoots and recessions among hunter-gatherers

We propose a model that may explain long-term population growth and decline events among human populations: The intensification of production generates a tradeoff between the adaptive capacity of individuals to generate a surplus of energy to maximize their fitness in the short-run and the long-term capacity of a population as a whole to experience a smooth transition into a demographic equilibrium. The model reconciles the conflicting insights of dynamic systems models of human population change, and we conduct a preliminary test of this model’s implications in Central Texas by developing time-series that estimate changes in human population density, modeled ecosystem productivity, human diet, and labor over the last 12,500 years. Our analysis indicates that Texas hunter-gatherers experienced three long-term population growth overshoots and recessions into quasi equilibria. Evidence indicates that each of these overshoots and recessions associate with changes in diet and labor devoted to processing high density, lower quality resources to unlock calories and nutrients. Over the long-term, population recessions may be necessary for populations to experiment with social and physical infrastructure changes that raise the carrying capacity of their environment.

Study on Urban Expansion and Population Density Changes Based on the Inverse S-Shaped Function

For decades, the continuous advance of urbanization has led to the continuous expansion of urban land and rapid increase in the total area of cities. The phenomenon of urban land expansion faster than population growth has become widespread. High population density can lead to problems such as traffic congestion and exacerbated air pollution and can hinder sustainable development, affecting the quality of life of urban residents. China is currently in a phase of rapid urbanization, with high urban population density and rapid decline in urban population density. The decrease in urban population density is conducive to promoting sustainable urban development. This study selected 34 cities in China as sample cities and analyzed the spatial expansion and population density changes using land use and population density data from 2000, 2005, 2010, 2015, and 2020 in order to provide reference for controlling population density and promoting sustainable urban development. The conclusions of the study are as follows: In the 34 sample cities, the average urban radius was only 11.61 km in 2000, but reached 17.98 km in 2020, with an annual growth rate of 2.5%. There were significant spatial differences in urban expansion. Beijing and Shanghai, as the most developed cities in China, had urban radii exceeding 40 km, while the less developed cities of Liaoyang and Suzhou had urban radii of only 9 km. Although the population density decreased in most cities, the population density values in first-tier cities in China, such as Tianjin, Beijing, and Shanghai, continued to rise. Cities with loose spatial expansion patterns had faster decreases in population density than compact-type cities. The rate of urban spatial expansion was negatively correlated with changes in population density, with cities that had faster urban spatial expansion also having faster declines in artificial ground density.

Population Dynamics and Its Driving Forces in China from 2000 to 2020

Exploring population dynamics and its driving factors has important practical significance for guiding reasonable population distribution. In view of this, this paper systematically analyzes the population dynamics and driving factors in China based on the latest three decennial censuses, using research methods such as the population concentration index, the center of gravity model, relative change in population density and multiple linear regression. The conclusions are as follows: (1) China’s population distribution is uneven, and the trend of polarization in population distribution is increasingly evident. The spatial differences in population growth are shifting from east–west to north–south. Under the influence of the “core–periphery effect”, more people are gathering in a few large cities. (2) The factors affecting population changes have obvious temporal variability: terrain and temperature have an increasing impact on China’s population changes. Temperature in particular has become an important factor in China’s population changes. Population changes are gradually shifting from being driven by a single economic factor to being driven jointly by social and economic factors. (3) The factors affecting population changes also have obvious spatial heterogeneity: temperature affects population changes in both the eastern and central–western regions, while terrain only affects population changes in the central–western regions. Currently, population changes in the economically developed eastern region are more driven by economic factors, while the central–western regions are driven by both economic and social factors. Central cities in the central–western regions are experiencing accelerated population agglomeration, while central cities in the eastern region are losing their ability to attract population agglomeration. The above conclusion basically clarifies the patterns and influencing factors of China’s population changes since the 21st century, which can provide a useful reference for future population development and regional planning.

Camera Trap Methods and Drone Thermal Surveillance Provide Reliable, Comparable Density Estimates of Large, Free-Ranging Ungulates.

Camera traps and drone surveys both leverage advancing technologies to study dynamic wildlife populations with little disturbance. Both techniques entail strengths and weaknesses, and common camera trap methods can be confounded by unrealistic assumptions and prerequisite conditions. We compared three methods to estimate the population density of white-tailed deer (Odocoileus virgnianus) in a section of Pilot Mountain State Park, NC, USA: (1) camera trapping using mark-resight ratios or (2) N-mixture modeling and (3) aerial thermal videography from a drone platform. All three methods yielded similar density estimates, suggesting that they converged on an accurate estimate. We also included environmental covariates in the N-mixture modeling to explore spatial habitat use, and we fit models for each season to understand temporal changes in population density. Deer occurred in greater densities on warmer, south-facing slopes in the autumn and winter and on cooler north-facing slopes and in areas with flatter terrain in the summer. Seasonal density estimates over two years suggested an annual cycle of higher densities in autumn and winter than in summer, indicating that the region may function as a refuge during the hunting season.

Habitat quality affects the social organization in mouse lemurs (Microcebus griseorufus)

Species can either maintain a certain social organization in different habitats or show different social organizations in similar habitats. The reasons underlying this variability are not always clear but might have consequences for population dynamics, especially under changing environmental conditions. Among mammals, the primate genus Microcebus lives in small groups of closely related females, derived from female philopatry and dispersed males, as illustrated by the well-studied Microcebus murinus. Here, we studied the genetic structure of a population of the congeneric Microcebus griseorufus, inhabiting three adjacent habitats with different resource availabilities. In order to learn more about the plasticity of the species’ social organization under these different conditions, we analyzed the spatial arrangement of mitochondrial haplotypes of 122 individuals. The study revealed high haplotype diversity and a pronounced difference in spatial distribution between the sexes. Females exhibited spatial aggregation of haplotypes, suggesting a system of female philopatry and matrilines, similar to M. murinus. Male haplotypes were dispersed, and males were more likely to carry rare haplotypes, indicating higher dispersal activity. These findings hint towards the unity of the social organization across the genus Microcebus, suggesting a phylogenetic origin of the social organization. Yet, with decreasing resources, the clustering of female haplotypes declined and approached a random distribution in the marginal habitat, with cluster sizes correlating with resource availability as predicted by the socioecological model. Our study supports the notion that social organization is shaped by both phylogenetic origin and ecological conditions, at least in these small primates.Significance statementImpacts of habitat degradation are mostly described in terms of changes in population densities in relation to the reduction of resources. This neglects the possible effects of altered social organizations due to declining resources or population densities. Using a genetic sampling of three subpopulations of mouse lemurs in Madagascar along a gradient of food availability up to the limit of the species’ ecological tolerance, we show that their social organization consisting of spatial clusters of closely related females and overdispersed males converges towards random spatial distributions of both sexes with declining food availability.

Evidence for density-dependent effects on body composition of a large omnivore in a changing Greater Yellowstone Ecosystem.

Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance-density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance-density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 1758) in the Greater Yellowstone Ecosystem, with estimates of body composition (lean body mass and percent body fat) serving as indicators of individual performance over two decades (2000-2020) during which time pronounced environmental changes have occurred. Several high-calorie foods for grizzly bears have mostly declined in recent decades (e.g., whitebark pine [Pinus albicaulis, Engelm, 1863]), while increasing human impacts from recreation, development, and long-term shifts in temperatures and precipitation are altering the ecosystem. We hypothesized that individual lean body mass declines as population density increases (H1), and that this effect would be more pronounced among growing individuals (H2). We also hypothesized that omnivory helps grizzly bears buffer energy intake from changing foods, with body fat levels being independent from population density and environmental changes (H3). Our analyses showed that individual lean body mass was negatively related to population density, particularly among growing-age females, supporting H1 and partially H2. In contrast, population density or sex had little effect on body fat levels and rate of accumulation, indicating that sufficient food resources were available on the landscape to accommodate successful use of shifting food sources, supporting H3. Our results offer important insights into ecological feedback mechanisms driving individual performances within a population undergoing demographic and ecosystem-level changes. However, synergistic effects of continued climate change and increased human impacts could lead to more extreme changes in food availability and affect observed population resilience mechanisms. Our findings underscore the importance of long-term studies in protected areas when investigating complex ecological relationships in an increasingly anthropogenic world.

Evaluación de polisacáridos en floculación mediada por complejo polielectrolítico

Water is an increasingly valuable resource because its availability, primarily it is limited to precipitation and water storage; for that reason, increasing population density and climate change can interfere with water accessibility. Urban and industrial activities can produce wastewater and pollute waterbodies that could represent a significant water source; however, it needs to be treated prior to its use. Flocculation is an important pollutants removal method to reduce a variety of organic and inorganic molecules from wastewater, using the flocculant’s intrinsic charges to stabilize/precipitate them, by different methods, one of them being via polyelectrolyte complex. Flocculant versatility depends on its capacity to remove pollutants and there are commercial flocculants with remarkable efficiencies. However, their toxicity can limit their use in waterbodies or for former human use. Research shows that polysaccharides are great option as flocculants because of their easily charged conformation and high molecular weight to neutralize pollutants and precipitate flocs, they are biocompatible, biodegradable, and easy to modify to modulate the flocculant interaction due to the functional group’s high density. This review explores the latest research on polysaccharide polyelectrolyte flocculation and derivatives and their pollutant removal capacity, the polysaccharides evaluated were the most commonly researched such as chitosan, cellulose, chitin, alginate, gums, dextran, among others. Recent research tendencies on these polysaccharides flocculation capacity, showed promising results (up to 99% removal efficiencies) with a wide variety of contaminants, making them excellent candidates for their application in green flocculation.

Estimate of population density and diagnosis of main factors of spatial heterogeneity in the metropolitan scale, western China

We estimated the population density and quantified its characteristics using remote sensing, census data, and Geographic Information System (GIS). The interactive influence of these factors on population density was quantified based on geographic detectors to identify the differentiation mechanisms in the Chengdu metropolitan area of China. We identified the key factors that contribute to population density growth. The models used to simulate population density had the highest R2 values (>0.899). Population density tended to increase with time, with a multicentre spatial agglomeration pattern; the centre of gravity of the spatial distribution tended to move from the southeast to the northwest. Industry proportions, Normalised Difference Vegetation Index (NDVI), land use, distance to urban centers or construction land, and GDP per capita can satisfactorily explain population density changes. The combined impact of these elements on population density variation exhibited mutual and non-linear strengthening, with the mutual effect of the two elements intensifying the impact of each individual element. Our study identified the key driving forces that contribute to the differentiation of population density, which can provide valuable support for the development of effective regional and targeted population planning guidelines.

Suitability of NASA’s Black Marble Daily Nighttime Lights for Population Studies at Varying Spatial and Temporal Scales

This paper investigates the potential link between changes in NASA’s Black Marble VIIRS/NPP Gap-Filled Lunar BRDF-Adjusted Nighttime Lights Daily L3 Global 500 m Linear Lat Lon Grid (VNP46A2) nighttime lights product (NTL) and human dynamics, particularly population counts and changes at a variety of spatial and temporal scales. We conducted analyses in four case studies at varying resolutions to explore the relationship of NTL data for population studies, including demographic research, disaster mitigation and adaptation planning, and infrastructure development. The analyses were conducted using different administrative geographies, including a refugee camp, a subnational region, and a country. We compared changes in population counts, density, migration, and displacement against changes in daily, weekly, monthly, and annual NTL values. Our case study results demonstrate that out-migration does not always lead to a decrease in NTL. We found that rural population decline did not correspond to a decrease in NTL. Despite significant out-migration in many rural areas NTL remained largely unchanged. NTL provided essential information on infrastructure damage in the short-term aftermath of this disaster; however, NTL alone was not correlated to the location of displaced individuals. Through news reports, we were able to corroborate the NTL changes to downtimes of the electrical systems. Monthly NTL averages were highly correlated to population counts, but a pixel-level analysis showed that the changes in NTL were primarily attributed to economic diversification. In summary, NTL is the product of several factors including demographic, environmental, economic, and political forces that shape electricity infrastructure, and we suggest that NTL data must first be parameterized with ancillary ground-level information in order to be effectively applied to population models.

Redundant actions of neuropeptides encoded by the dh-pban gene for larval color pattern formation in the oriental armyworm Mythimnaseparata

The pyrokinin (PK)/pheromone biosynthesis-activating neuropeptide (PBAN) family, which is defined by a conserved C-terminal pentapeptide (FXPRLamide), is involved in many physiological processes in insects. In the oriental armyworm Mythimna separata, the larvae exhibit a variety of color patterns in response to changes in population density, which are caused by melanization and a reddish coloration hormone (MRCH), which is a member of the FXPRLamide neuropeptides. Interestingly, in some lepidopteran insects, MRCH is known as a PBAN, which activates the pheromone gland to produce sex pheromones. PBAN is encoded by a single gene, dh-pban, which encodes additional FXPRLamide neuropeptides, such as the diapause hormone (DH) and subesophageal ganglion neuropeptides (SGNPs). To determine the roles of the dh-pban gene, which produces multiple types of FXPRLamide neuropeptides after post-transcriptional cleavage of the precursor protein, we performed CRISPR/Cas9-mediated targeted mutagenesis in M. separata. We demonstrated that knockout armyworm larvae lost density-dependent cuticular melanization and retained yellow body color, even when reared under crowded conditions. Moreover, our rescue experiments using the synthetic peptides showed that not only PBAN but also β- and γ-SGNPs significantly induce the cuticular melanization in a dose dependent manner. Taken together, our results provide genetic evidence that neuropeptides encoded by the single dh-pban gene act redundantly to control density-dependent color pattern formation in M. separata.

Temporal-spatial monitoring of population growth with RS-GIS technology at Wasit province of Iraq

In this study, the growth rate of the population in a spatial-temporal manner has been modeled and explored by relying on the data from remote sensing and using the analytical functions of the geographic information system in Wasit province of Iraq during the period from 2000 to 2020. WorldPop layers were used to prepare population maps and forecast it in 2025 with the help of artificial neural networks. The predictive model was highly accurate (R 2 = 0.98). The next step was to measure the relationship between the rate of population growth and the changes in water areas and the primary production of vegetation with the help of time series of satellite data, which showed the distribution of the population. It is denser in the central, northwestern and southeastern areas of Wasit province. Low density populations have higher frequency. While from 2015 onwards, the frequency of some population classes with higher density increased compared to lower densities. In general, the trend of changes in the average population in the study area has been completely linear. But the maximum annual population density changes were upward and nonlinear. Changes in the area of ​​deciles representing denser areas have increased and the area of ​​deciles representing less densely populated areas has faced a decrease. The results and findings of this study showed that NPP changes were less predictable compared to population density changes because it is a complex function of climatic and human factors. In the estimated population density map in 2025, dense population cores have been formed in the northeastern areas of Wasit province in the vicinity of the border areas with Iran.

JUSTIFICATION OF A NEW MODEL OF MUNICIPAL DISTRICT MANAGEMENT IN THE CONTEXT OF TERRITORIAL PLANNING

Since 2003, the administrative-territorial division in Russia existed as part of rural and urban settlements, municipal districts, urban districts, intracity territories. This system of territorial division showed its ineffectiveness in terms of the timeliness of solving local problems and the quality of territorial planning, since local authorities constantly experienced personnel "hunger," lack of funding. In addition, external and internal migration of the population contributed to the change in population density in certain territories, to the demand for existing objects of social, engineering and transport infrastructure. Since 2019, municipal districts have been introduced, which, according to the criterion of population density and with the consent of citizens, unite rural settlements. Accordingly, changes are predicted in the compilation of territorial planning documents - master plans for rural settlements. The main problems of drawing up and applying master plans for the development of territories were considered, the economic effectiveness of creating municipal districts in the context of territorial planning was justified on the example of one of the districts of the Udmurt Republic. Centralization of management will save budget funds, establish information collection and optimize territorial planning processes, update and create new master plans for the development of territories, and increase the investment attractiveness of territories.

Affecting of Nature and Human Activities on the Trend of Vegetation Health Indices in Dak Nong Province, Vietnam

This study aims to evaluate the effects of natural and human conditions on vegetation covers using VCI and TCI indices (the satellite-based Vegetation Health Indices (VHIs)) in Dak Nong province. Factors affecting the VHIs included in the analysis involve land use, soil, population, topography, distance to roads and surface water. The data analysis period is the dry season from 2000 to 2020. The trend of the VHIs’ change in this study is analyzed using Sen’s method with monitoring data from Modis. The effects of factors affecting the VHIs are based on logistic regression and discriminant analysis. The analysis results show that the VHIs are clear and show both increasing and decreasing trends. Based on logistic regression analysis, the influence of land use types on the trend of the VHIs in the direction of increasing from negative to positive will be from PdF, UnL, AnC, SpF, PtF, PeA and then to PdR. Corresponding to the soil will be from ACa, FRp, FRx, FRr, ACh, LVx, FLg and then to LVg. Based on the discriminant analysis method, it was found that there are only four primary factors affecting the trend of the VHIs in order of decreasing level of closure: population density, land use, soil and population growth rate and to the road. These results show that in places where labour resources are available, plants are interested in investment due to high profits, nutrient-rich soil and convenience for plant care; the VHIs tend to increase and vice versa. Compared with VCI, the trend of TCI tends to be sloping negative and more pessimistic. Through the coefficients of the logistic regression equation and the difference function, the TCI is more sensitive than the VCI when the independent variables change, especially for changes in population density and land use. Thus, TCI can be considered the preferred option for assessing vegetation health trends in the context of climate change.

ВЛИЯНИЕ ТЕРРИТОРИАЛЬНЫХ ОСОБЕННОСТЕЙ НА ДЕЯТЕЛЬНОСТЬ ПРАВООХРАНИТЕЛЬНЫХ ОРГАНОВ СИБИРСКОГО КРАЯ (1925-1930 гг.)

Based on published materials and previously unpublished archival sources, the paper analyzes the impact of territorial features of Siberia on the activities of law enforcement agencies during the existence of the Siberian Krai (1926-1930). The author examines the overall criminogenic situation, the effectiveness of law enforcement agencies and their shortcomings stemming from the territorial features of Siberia: vast amounts of space, low population density, ethnic territories, complex terrain, climatic and seasonal changes. The author argues that, combined with the lack of communication and transportation means, these features created special conditions for the development and formation of law enforcement agencies that are not characteristic of the system on the national scale.

Resistance of the citrus rootstock forner-alcaide 5 to Tylenchulus semipenetrans in replant situations

The resistance of the citrus rootstock Forner-Alcaide 5 to Tylenchulus semipenetrans was assessed in comparison to the susceptible Carrizo citrange (S) in two replant situations. Changes in soil and root population densities were monitored after planting the new trees to detect tree infection and nematode population growth over time. The efficacy of pre-plant control methods such as fumigation with 1,3 Dichloropropene (1,3D) or 2-year fallowing was also assessed. Fumigation and fallowing reduced juveniles + males/250 cm3 soil to undetectable levels for 3 and 2 years, respectively, and postponed root parasitism on Forner-Alcaide 5 for 3 and 2.5 years, respectively. Forner-Alcaide 5 supported lower densities of juveniles + males/250 cm3 soil and females/g root than Carrizo citrange in both replant situations The efficacy of the resistant rootstock was enhanced when combined with 1,3D fumigation or 2-year fallowing because the pre-planting control reduced densities of juveniles + males in soil before establishing the orchard, and the resistant rootstock, the female densities in the roots. Selection for virulence within the field population did not occurr after 9-years of exposure of Forner-Alcaide 5 to the nematode. The durability of the resistance can be enhanced by combining rootstock resistance with pre-planting control methods in order to delay root parasitism, and therefore, diminish the selection pressure exerted on the resistant rootstock. Forner-Alcaide 5 exibited higher scion diameter and yield than Carrizo citrange.