Establishing the ecological planning principles from empirical studies in agricultural environments of Taiwan

Studies have suggested that the heterogeneity and arrangement of landscape structures are influential to the faunal biodiversity of environments. How does the landscape structure in agricultural landscape arrangements improve the functions of the natural ecosystem? Previous research has uncovered a great amount of information on the relationships between landscape structure and wildlife; however, for landscape designers and planners, such information is site-specific and has limited utilization. Hence, this study aimed to organize and categorize the relationships between environments and biodiversity and transfer this information into design principles in agricultural landscapes. This study attempted to integrate aspects of previous research into a systematic framework. The current study searched literature between 2007 and 2016 from the following journals: Landscape Ecology, Landscape and Urban Planning, and Journal of Applied Ecology. In all, this study collected 58 empirical studies of agricultural environments similar to that of Taiwan and revealed the valuable relationship between wildlife and agricultural environments. The outcomes reviewed from the literature were categorized by semi-natural elements and divided into six sub-categories: forests, hedgerows, grasslands, flowers, water, and heterogeneity of the natural landscape. The landscape attributes that were frequently discussed included patch number, patch area, connectivity, species richness, edge area, distance from semi-natural elements, and complexity. The landscape attributes formed by these elements were organized into a table as a checklist for designers’ convenience. The checklist will help landscape planners and designers to create agricultural landscapes with integral ecosystems.

     

Location and amino acid sequence around the ADP-ribosylation site in the cholera toxin active subunit A1

Renatured, S-carboxymethylated subunit A₁ of cholera toxin possess the ADP-ribose transferase activity (Lai, et.al., Biochem. Biophys. Res. Commun. 1981, $\text{102}$, 1021). In the absence of acceptor self ADP-ribosylation of A₁ subunit was observed. Stoicheometric incorporation of ADP-ribose moiety was achieved in 20 min at room temperature in a 0.1 – 0.2M PO₄(Na) buffer, pH 6.6. On incubation of the complex with polyarginine, 75% of the enzyme-bound ADP-ribose moiety was transferred to the acceptor in 25 min. The ADP-ribosylated A₁ was stable at low pH, and on cleavage with BrCN, the ADP-ribose moiety was found associated with peptide Cn I, the COOH-terminal fragment of A₁ subunit. On further fragmentation with cathepsin D, a dodecapeptide containing ADP-ribose moiety was isolated whose structure was determined as: Asp-Glu-Glu-Leu-His-Arg-Gly-Tyr-Arg¹-Asp-Arg-Tyr. The Arg¹ in the peptide was indicated to be the site of ADP-ribosylation.     

Special issue: Local landscape planning and management in rural areas

Landscape and Ecological Engineering -