Spatial dispersion patterns of trees at different life stages are an important aspect to investigate in understanding the mechanisms that facilitate species coexistence. In this paper, Ripley's univariate L(r) and bivariate L 12 (r) functions were used to analyze spatial distribution patterns and spatial associations across different life stages of 131 tree species in a 20-ha plot of a tropical rainforest in Xishuangbanna, southwest China. Our results show that: (1) Saplings of 109 (83.2%) species have a significant clumped distribution, which confirms the ubiquity of clumped spatial distributions among tropical tree species.(2) Adults of 126 (96.2%) species have a random distribution suggesting that density-dependent mortality can make the spatial pattern of tropical trees more regular with time.(3) At small scales (0-10 m), 95 (72.5%) species have a neutral or negative sapling-adult association, implying that there is recruitment limitation within the vicinity of their conspecific adults. The reduction in spatial clumping in going from younger to older life stages and the neutral or negative sapling-adult association imply densitydependent mortality in the vicinity of adult trees. In accordance with the Janzen-Connell hypothesis, such density-dependent mortality can free up space for other species to colonize, contributing to the maintenance of species diversity.

Highlights• Direct green façades (DGFs) are being applied to buildings in high density cities.• A new methodology to evaluate DGFs' fine-scale cooling effect is presented.• DGF enables 4.67 and 8.03 °C maximum surface temperature reduction compared to bare wall at overall and pixel scales.• DGF cooling effect is most obvious around midday and significantly decreases at night.• Surface temperatures of DGF exhibit significant spatial variations at pixel scale. AbstractThermal regulation is a key ecosystem service provided by direct green façades (DGFs), as vegetated walls absorb short wave radiation, reduce solar re-radiation from hard surfaces, and provide cooling due to shading and evapotranspiration. Few studies have investigated the correlation between the cooling effect of DGFs and vegetation characteristics at a fine spatial and temporal scale. This paper presents a new methodology to evaluate the cooling effect of DGFs related to fine-scale plant characteristics for hot summer days using thermal infrared (TIR) and three-dimensional point cloud (3DPC) data, through a case study conducted at the Executive Office Building on Nanjing University's Xianlin Campus, China. Results show that daily mean DGF surface temperature is significantly lower than the average bare wall surface temperature, with a maximum reduction of 4.67 °C. The cooling effect of the DGF is most obvious during midday (10:30 h to 16:00 h) and significantly decreases at night. At the pixel scale, the DGF exhibits a significant spatial variation of surface temperatures, which may be closely related to the DGF's canopy structure. Among the four vegetation indices acquired based on 3DPC data, the percentage of green coverage and the cooling effect of the DGF exhibited a linear relationship, while plant thicknesses, point density, and volume of the green façade were power function distributions. Incoming solar radiation and air temperature are the dominant independent variables in cooling effect and surface temperature fitting models. Our findings can guide DGF design to cool the thermal environment more effectively and to enhance building energy savings.

The objectives of this study were to compare the influence of land use, to determine which land has an impact on hydrochemistry and to clarify the impact of land use on soil microbial diversity and the correlation between hydrochemistry and soil microbial diversity. The impacts were assessed through chemical and biological data from 4 land-use groups. The results showed that soil microbial diversity and water chemical composition were different under different land uses. There was a strong correlation between the main hydrochemical components under different land uses, and the M03 had the highest correlation. The Shannon index was the largest for M01, the Simpson index was the smallest for M01, and the Chao1 and Ace indexes were the largest for M02. Actinobacteria, Proteobacteria and Acidobacteria were the dominant bacteria with different land uses, and some bacteria were present or absent depending on the land use. It was found that the soil CO2 content was different with different land uses. Soil CO2 content, hydrochemistry and soil microbial species were related to each other. A heatmap analysis showed that the F− and soil CO2 content showed a strong correlation with soil microorganisms and that the dominant bacteria were positively correlated. Under different land uses, hydrochemistry, soil CO2 and soil microorganisms interact with one another.

No abstract

In this paper, we study continuous frames from projective representations of locally compact abelian groups of type Ĝ × G . In particular, using the Fourier transform on locally compact abelian groups, we obtain a characterization of maximal spanning vectors. As an application, for G, a compactly generated locally Euclidean locally compact abelian group or a local field with odd residue characteristic, we prove the existence of maximal spanning vectors, hence the phase retrievability, for the associated ( Ĝ × G)-frames.