Effects of Land Cover Pattern Along Urban-Rural Gradient on Bird Diversity in Wetlands

Abstract

Wetlands play an important role in the feeding, breeding, and lives of birds. However, available habitats for bird species are changing due to intensifying human activity, especially in the context of China’s mass urbanization. Urban sprawl has taken over the wetlands along the lakes in the past decades, which places tremendous pressure on wetland ecosystems and, therefore, on bird communities. However, the ways urban land cover pattern along the urban-rural gradient affects bird communities is still unclear. To investigate the influence of land cover pattern on the α and β diversity of birds in the urban-rural gradient we chose 31 sites distributed within the wetlands around the Dianchi Lake in Yunnan, China. We calculated the species richness to indicate α diversity and used the Morisita–Horn index to indicate β diversity. Meanwhile, we assessed the land cover pattern of each site by measuring the proportion of emergent plants, floating plants, submerged plants, ponds, forests, lawns, roads, agricultural lands and built lands in a quadrat of 1 square kilometer. Simple linear regressions, model selection, and an averaging approach based on corrected Akaike information criterion (AICc) were used to test the effects of land cover pattern on bird diversity. Using one-way ANOVA and Tukey’s HSD (honestly significant difference) test, we compared the difference between α and β diversity, respectively, along the urban-rural gradient. Based on our analyses, urban and suburban wetland birds were significantly homogeneous. The community structure in rural wetlands, however, was significantly different from that of the suburban and urban areas. According to our research, the land cover patterns that influenced bird species richness were the built lands acreage, submerged plants acreage, ponds acreage, and the edge density of emergent plants. Meanwhile, of these variables, the built lands acreage, ponds acreage and edge density of emergent plants were significantly different in urban, suburban, and rural wetlands. Therefore, to maintain high biodiversity in wetlands affected by urbanization, we must pay more attention to the land cover patterns.

Behavioral plasticity mediates adaptation to changes in food provisioning following the COVID-19 lockdown in black-headed gulls (Larus ridibundus)

“…Dianchi Lake (24°40′-25°02'N, 102°37′-102°48′E) is located on the Yunnan-Guizhou Plateau in southwestern China (Mao et al, 2019; Figure 1); it has an area of 308.6 km 2 and an average elevation of 1,888 m a.s.l. (Wang et al, 2021).…”

Propuesta de humedales artificiales, impulsores de biodiversidad, que depuran aguas contaminadas para la recuperación de lagunas urbanas de Concepción, Chile

“…En los casos que no se cuenta con humedales naturales se debe recurrir a humedales artificiales (Figura 4), como hábitat de macrófitas, los cuales desempeñan un papel importante en la alimentación, la reproducción y la vida de las aves, más aún cuando la expansión urbana se ha apoderado de los humedales en las últimas décadas, lo que ejerce una presión enorme sobre estos ecosistemas y, por lo tanto, sobre las comunidades de aves (Mao et al, 2018). Las actividades humanas, especialmente la conversión y degradación de hábitats, están causando disminuciones en la biodiversidad global, pero medidas de mitigación efectivas pueden generar cambios favorables en la biodiversidad (Newbold et al, 2015).…”

“…Desde el punto de vista urbanoambiental, este tratamiento da origen a una combinacion laguna-humedal que es armónica paisajísticamente y potencia la biodiversidad. La presencia de este tipo de hábitat particulares (humedales, pastizales, terrenos boscosos), distribuidos en la matriz urbana, podría amortiguar los efectos nocivos de la urbanización en las aves (Rodrigues, Borg(Rodrigues, Borques-Martins y Zilio, 2018) es-Martins y Zilio, 2018) y otros seres vivos de manera que el humedal, además de tratar las aguas, genera un hábitat que debe considerarse desde la planificación urbana por sus efectos en la urbe (Mao 2018).…”

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