RESUMO
Landscape planning is clearly ecologically and socially relevant. Concern about sustainability between human and environment is now a driving paradigm for this professional. However, the explosion of the sustainable landscape in China is a very recent phenomenon. What is the sustainable landscape? How is this realized in practice? In this article, on the basis of the reviews of history and perplexities of Chinese landscape and nature analysis of sustainable landscape, the ecothinking model, an implemental tool for sustainable landscape, was developed, which applies ecothinking in vision, culture, conservation and development of site, and the process of public participation for a harmonious relationship between human and environment. And a case study of the south entrance of TongNiuling Scenic Area was carried out, in which the most optimum scenario was chosen from among three models according to the ecothinking model, to illustrate the construction of the ecothinking model and how to achieve a sustainable landscape.
Assuntos
Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Ecossistema , Planejamento Ambiental/tendências , Plantas , HumanosRESUMO
Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillus fusiformis. Its algaelysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that: (1) the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; (2) the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesmus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 x 10(7) cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 microg/L, about 70% was removed; (3) the strain B5 lysed algae by secreting metabolites and these metabolites could bear heat treatment.
Assuntos
Chlorella/citologia , Microcystis/citologia , Scenedesmus/citologia , Carbono , Contagem de Células , Morte Celular , Chlorella/crescimento & desenvolvimento , Clorofila/metabolismo , Clorofila A , DNA Ribossômico/genética , Bases de Dados de Ácidos Nucleicos , Eutrofização , Microcystis/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Scenedesmus/crescimento & desenvolvimento , Análise de Sequência de DNA , Esgotos/microbiologiaRESUMO
A new LOS2 gene was cloned from C. bursa-pastoris by rapid amplification of cDNA ends (RACE). The full-length cDNA of C. bursa-pastoris LOS2 gene (designated as Cblos2) was 1694 bp containing a 1332 bp open reading frame (ORF) encoding a 444 amino acid protein. The predicted CbLOS2 protein contained enolase-N domain, enolase domain, conserved putative DNA-binding and repression domains like LOS2 from A. thaliana. Bioinformatic analysis indicated that CbLOS2 had similarity with other enolase proteins. Cold acclimation assay revealed that Cblos2 expressed constitutively in C. bursa-pastoris and was involved in the cold acclimation process, implying CbLOS2 was a bi-functional enolase.