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31.
This study provides a method for assessing a multiplicity of environmental factors in red spruce growth in the Great Smoky Mountains National Park (GSMNP) of Southeastern USA. Direct and indirect factors in the annual growth increment are first organized into a schematic input-output envirogram (ARIRS), and this information is then used to construct a simulation model (ARIM). The envirogram represents a structured conceptualization of most environmental factors involved in growth, as developed from relevant literature. This interdisciplinary synthesis distinguishes direct vs. indirect factors in growth and takes account of the systems ecology concept that indirect factors may be as important as or more important than direct ones in regulating growth. The ARIRS envirogram summarizes hierarchically organized, within- and cross-scale, local-to-global interactions, and its construction makes it obvious that growth is influenced by many cross-scale spatiotemporal interactions. More research on genecology is still needed to clarify the role of phenotypic plasticity and adaptive capacity in nutrient cycling, global change, and human disturbance. 相似文献
32.
Ok K. Koo Hun Kim Hyun J. Kim Christopher A. Baker Steven C. Ricke 《Journal of environmental science and health. Part. B》2016,51(7):490-496
Tatsoi (Brassica narinosa) is a popular Asian salad green that is mostly consumed as a source of fresh produce. The purpose of this study was to assess the microbial diversity of Tatsoi cultivated in a hydroponic system and of its ecosystem. Tatsoi leaves, nutrient solution, and perlite/earth samples from a trickle feed system (TFS) and an ebb-and-flow system (EFS) were collected and their microbial communities were analyzed by pyrosequencing analysis. The results showed that most bacteria in the leaves from the TFS contained genus Sporosarcina (99.6%), while Rhizobium (60.4%) was dominant in the leaves from the EFS. Genus Paucibacter (18.21%) and Pelomonas (12.37%) were the most abundant microbiota in the nutrient solution samples of the TFS. In the EFS, the nutrient solution samples contained mostly genus Rhodococcus and Acinetobacter. Potential microbial transfer between the leaves and the ecosystem was observed in the EFS, while samples in the TFS were found to share only one species between the leaves, nutrient solution, and earth. Together, these results show that the bacterial populations in Tatsoi and in its ecosystem are highly diverse based on the cultivation system. 相似文献
33.
Pal R Kim KH Jeon EC Song SK Shon ZH Park SY Lee KH Hwang SJ Oh JM Koo YS 《Environmental monitoring and assessment》2009,148(1-4):109-125
The atmospheric concentrations of several reduced sulfur compounds (RSCs) including H(2)S, CH(3)SH, DMS, CS(2), and DMDS were measured concurrently from a series of field campaigns covering multiple locations in the surroundings of a large industrial region (August 2004 to September 2005). These field studies have been designed and undertaken to inspect the concentrations of RSCs in ambient air. The RSC concentrations were found to occur in a highly variable range. H(2)S (1.06 +/- 2.07 ppb) was found to be the most abundant RSC followed by CS(2) (0.84 +/- 0.54 ppb), DMDS (0.36 +/- 1.21 ppb), DMS (0.24 +/- 0.83 ppb), and CH(3)SH (0.11 +/- 0.23 ppb). The RSC levels measured at the study area were comparable to those observed previously from other polluted environmental settings. When these RSC data were examined further in terms of spatial (industrial vs. non-industrial sites) and seasonal (summer vs. winter seasons) grouping schemes, differences in their concentration levels were statistically insignificant in most cases. In contrast, there were fairly strong variations in temporal patterns over a diurnal cycle. If these RSC concentration data were converted to diagnose the malodor strengths, their effects were in most cases insignificant with minor contribution towards odor nuisances. 相似文献