The scaling relationship between leaf dry mass and leaf surface area has important implications for understanding the ability of plants to harvest sunlight and grow. Whether and how the scaling relationships vary across environmental gradients are poorly understood. We analyzed the scaling relationships between leaf mass and leaf area of 121 vascular plant species along an altitudinal gradient in a subtropical monsoon forest. The slopes increased significantly with altitude, it varied from less than 1 at low altitude to more than 1 at high altitude. This means that plants growing at high altitude allocate proportionately more biomass to support tissues in larger leaves and less in smaller leaves, whereas the reverse is true at low altitude. This pattern can be explained by different leaf strategies in response to environmental pressure and constrains.
Reference evapotranspiration (ET 0 ) is the key factor for hydrologic water balance, irrigation scheduling, and water resources planning. Based on Food and Agriculture Organization (FAO) Penman-Monteith method and the climate variables of 57 meteorological stations from 1960 to 2010 in southwest China, the spatial and temporal distributions of ET 0 were analyzed by using Mann-Kendall test and Sen's slope estimator. Sensitivity coefficient was used to analyze the sensitivities of ET 0 to four climate variables, and the key climate variables attributed to ET 0 change were determined. Result showed that there was a slight downward trend of ET 0 from 1960 to 2010 and spatially increasing trend from northeast to southwest in annual time scale. Results also showed that ET 0 had relatively higher sensitivity to wind speed and mean air temperature, and wind speed was the dominant variable for change of ET 0 in southwest China. The inverse relationship between increasing air temperature and decreasing evaporation, Bevaporation paradox,^existed in southwest China, and the negative contribution of wind speed to the changes of ET 0 offset the positive contribution of air temperature.
Large and growing data resources on the spatial and temporal diversity and distribution of the more than 400 carbon-bearing mineral species reveal patterns of mineral evolution and ecology. Recent advances in analytical and visualization techniques leverage these data and are propelling mineralogy from a largely descriptive field into one of prediction within complex, integrated, multidimensional systems. These discoveries include: (1) systematic changes in the character of carbon minerals and their networks of coexisting species through deep time; (2) improved statistical predictions of the number and types of carbon minerals that occur on Earth but are yet to be discovered and described; and (3) a range of proposed and ongoing studies related to the quantification of network structures and trends, relation of mineral "natural kinds" to their genetic environments, prediction of the location of mineral species across the globe, examination of the tectonic drivers of mineralization through deep time, quantification of preservational and sampling bias in the mineralogical record, and characterization of feedback relationships between minerals and geochemical environments with microbial populations. These aspects of Earth's carbon mineralogy underscore the complex coevolution of the geosphere and biosphere and highlight the possibility for scientific discovery in Earth and planetary systems.
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