scholarly journals Quantifying the links between land use and population growth rate in a declining farmland bird

2019 ◽  
Vol 9 (2) ◽  
pp. 868-879 ◽  
Author(s):  
Matthieu Paquet ◽  
Debora Arlt ◽  
Jonas Knape ◽  
Matthew Low ◽  
Pär Forslund ◽  
...  
2018 ◽  
Vol 10 (7) ◽  
pp. 2584 ◽  
Author(s):  
Andrea Colantoni ◽  
Ilaria Zambon ◽  
Maria Gras ◽  
Enrico Maria Mosconi ◽  
Alessandra Stefanoni ◽  
...  

This article presents empirical results of a multivariate analysis run with the aim to identify (apparent and latent) socioeconomic transformations that shape the distribution pattern of cropland in a metropolitan region of southern Europe (Athens, Greece) over a sufficiently long time interval spanning from 1960 to 2010. The study area is representative of monocentric cities expanding in an unregulated fashion and experiencing sequential cycles of economic growth and recession. Percent share of cropland in total municipal area increased moderately over time. A non-linear relationship with the distance from downtown Athens was also observed, indicating that the highest rates of cropland were observed at a distance ranging between 20 and 30 km from the inner city. A multivariate regression was run by decade at each municipality of the study area using 11 predictors with the aim to identify the factors most associated with cropland decline along urban fringes. Distance from downtown Athens, soil and climate quality, population growth rate, and competing land use were the most relevant factors correlated with cropland expansion (or decline) in the study area. Competing land use was particularly important for cropland decline in a first urbanization phase (1960–1980), while population growth rate—and hence an increased human pressure—was positively associated with agricultural areas in a subsequent phase (1990–2010). In these regards, per capita urban land had a non-linear spatial behavior, being correlated negatively with cropland in 1960 and 1970 and positively in 2010, possibly indicating a moderate change from a monocentric model towards a more dispersed metropolitan configuration impacting distribution of agricultural areas. Empirical findings of this study suggest that effective strategies supporting peri-urban agriculture require a comprehensive knowledge of the local socioeconomic context and relevant biophysical conditions—specifically focusing on the dominant soil and climate attributes.


Author(s):  
J. X. Zhang ◽  
G. Y. Cai

Abstract. The old city of Beijing represents the brilliant history and attracts people’s attention worldwide. With the rapid development of urbanization in Beijing, the old city is facing the problem that more and more people are working or living in this limited region. How to estimate the land use efficiency in the old city is crucial for the city planners to perform some policy-making decisions. Based on the Sustainable Development Goal 11 (SDG 11) which is to develop inclusive, safe, resilient and sustainable cities and human settlements, in which indicator SDG 11.3.1 is designed to testify the land use efficiency that is defined as a ratio between land consumption rate to population growth rate(PGR).This paper focus on how to evaluate the land use efficiency in the old city where the land is limited to a region while people are in a continuous growing. Based on the extraction of buildings from high resolution images with sub-meter spatial resolution in the area enclosed by the second-ring road which is mainly consists of Dongcheng and Xicheng districts, this study obtained the 3D building information including building height and floor numbers over years from 2005, 2010 to 2015 with the help of visually interpretation, POI information and the in situ investigation. By calculating the ratio of the building density growth rate(BDGR) to the population growth rate, the land use efficiency in the old city was computed for each year. Our results showed that most of the ratios are greater than 1 over year from 2005 to 2010 and less than 1 during periods from 2010 to 2015. Which means that the land use efficiency tend to lower from 2010 to 2015 than from 2005–2010. The reasons caused this phenomenon has been discussed in the discussion part. The results are helpful for local governors or managers to make a better decision in the protection and conservation of the old city, and to keep a sustainable old city.


2018 ◽  
Vol 8 (1) ◽  
pp. 10 ◽  
Author(s):  
Rita Nicolau ◽  
João David ◽  
Mário Caetano ◽  
José Pereira

This paper presents a methodological approach for the assessment of the indicator 11.3.1: “Ratio of Land Consumption Rate to Population Growth Rate” proposed by the United Nations (UN), discussing the definitions and assumptions that support the indicator quantification, and analysing the results provided by different formulations applied to mainland Portugal, at the municipality level. Due to specific limitations related to the actual formula proposed by the UN (LCRPGR) for the computation of the indicator, an alternative formulation derived from Land Use Efficiency (LUE) was explored. Considering that the land to which the indicator refers may be described by specific classes represented in Land Cover Land Use (LCLU) maps, in the estimation of the land consumption rate we tested two LCLU datasets: Corine Land Cover and COS—the Portuguese LCLU reference map. For the estimation of the population growth rate, prior allocation of inhabitants to the areas where people are most likely to reside was deemed necessary, using a dasymetric mapping technique based on LCLU information. The results obtained for 2007–2011 and 2011–2015 showed, in most municipalities, an increase in the urban area and a decrease in urban population, leading to negative values both in LCRPGR and LUE in most of the territory. Clearly, LUE performed better than LCRPGR in what urban development monitoring and urban area dynamics trends are concerned. Furthermore, LUE was much easier to interpret.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helena Bestová ◽  
Jules Segrestin ◽  
Klaus von Schwartzenberg ◽  
Pavel Škaloud ◽  
Thomas Lenormand ◽  
...  

AbstractThe Metabolic Scaling Theory (MST), hypothesizes limitations of resource-transport networks in organisms and predicts their optimization into fractal-like structures. As a result, the relationship between population growth rate and body size should follow a cross-species universal quarter-power scaling. However, the universality of metabolic scaling has been challenged, particularly across transitions from bacteria to protists to multicellulars. The population growth rate of unicellulars should be constrained by external diffusion, ruling nutrient uptake, and internal diffusion, operating nutrient distribution. Both constraints intensify with increasing size possibly leading to shifting in the scaling exponent. We focused on unicellular algae Micrasterias. Large size and fractal-like morphology make this species a transitional group between unicellular and multicellular organisms in the evolution of allometry. We tested MST predictions using measurements of growth rate, size, and morphology-related traits. We showed that growth scaling of Micrasterias follows MST predictions, reflecting constraints by internal diffusion transport. Cell fractality and density decrease led to a proportional increase in surface area with body mass relaxing external constraints. Complex allometric optimization enables to maintain quarter-power scaling of population growth rate even with a large unicellular plan. Overall, our findings support fractality as a key factor in the evolution of biological scaling.


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