Authors:Qiuju Zhou, Ronald Rousseau, Liying Yang, Ting Yue, and Guoliang Yang
‘Diversity’ is a concept that features prominently in a variety of disparate disciplines (Stirling 2007 ). Yet it is almost impossible to find a precise definition. In the nineties, Stirling ( 1998 ), following
Authors:N. C. Kenkel, N. C. Kenkel, D. A. Peltzer, D. A. Peltzer, D. Baluta, D. Baluta, D. Pirie, and D. Pirie
Hooper, D.U. and P.M. Vitousek. 1997: The effects of plant composition and diversity on ecosystem processes. Science 277 : 1302-1305.
The effects of plant composition and diversity on ecosystem processes
In two arid/semiarid regions, we studied diversity of algae in lakes and pools with salinity ranging from 0.1‰ up to 39‰ In plankton and periphyton of 34 lakes in northern Kazakhstan, we found 252 species belonging to 113 genera of 8 algal divisions. In 24 pools with experimental salinity ranges in the Negev desert of Israel, we recorded 86 species from 47 genera of 6 algal divisions. The dominant groups of both arid regions are represented by widespread species of diatoms, green algae, and cyanobacteria in similar proportions. Alkaliphiles among the indicators of acidification and betamesosaprobionts among the indicators of saprobity prominently prevail in both regions. The indices of saprobity in lakes (1.48–2.7) and in pools (0.75–2.18) reflect a low-trophic loading. Oligohalobes-indifferents are most common in both arid regions. Cluster analysis based on data containing 420 species revealed 9 clusters, of which the highly diverse communities of low mineralized lakes and pools and the low diversity communities of highly-mineralized lakes and pools are separated at the highest dissimilarity level. CCA analysis revealed correlation of the algal species diversity preferences with salinity level in lakes in Kazakhstan and in pools of Israel, which are more impacted by arid factors. These results point to mineralization being the most important variable defining the diversity levels irrespective of the type and location of reservoirs in the arid regions.
The multidimensional character and inherent conflict with categorisation of interdisciplinarity makes its mapping and evaluation
a challenging task. We propose a conceptual framework that aims to capture interdisciplinarity in the wider sense of knowledge
integration, by exploring the concepts of diversity and coherence. Disciplinary diversity indicators are developed to describe
the heterogeneity of a bibliometric set viewed from predefined categories, i.e. using a top-down approach that locates the
set on the global map of science. Network coherence indicators are constructed to measure the intensity of similarity relations
within a bibliometric set, i.e. using a bottom-up approach, which reveals the structural consistency of the publications network.
We carry out case studies on individual articles in bionanoscience to illustrate how these two perspectives identify different
aspects of interdisciplinarity: disciplinary diversity indicates the large-scale breadth of the knowledge base of a publication;
network coherence reflects the novelty of its knowledge integration. We suggest that the combination of these two approaches
may be useful for comparative studies of emergent scientific and technological fields, where new and controversial categorisations
are accompanied by equally contested claims of novelty and interdisciplinarity.