Current trends and future directions in quantitative geodiversity assessment

Abstract

Geodiversity assessment is recent and is passing through a stage of methodological development and consolidation. With rapid environmental change, improving the developmental states of geodiversity assessment is of paramount importance. A scientometric analysis is presented to identify knowledge gaps, current trends and avenues for future research in quantitative geodiversity assessment literature. The study is categorised into three areas of analysis: (a) methodological intentions of geodiversity assessment, (b) current trends in geodiversity assessment methods and (c) current geographic trends. A ranking tool was developed to determine whether the current methodological intentions of geodiversity assessments trend towards combined geodiversity and biodiversity assessments or towards the independent assessment of geodiversity. Results showed that about 50% of publications independently assessed geodiversity with no consideration for biodiversity, 32% discussed or reviewed geodiversity by mentioning potential links to biodiversity and 12% more strongly linked geodiversity assessment to biodiversity assessment. Tools used by scholars to determine geodiversity values varied from statistical through to the more frequently adopted geographic information systems (GIS) and spatial analytical software approaches. Study sites selected for geodiversity assessments were predominantly terrestrial at the state-wide scale. Marine assessments, or seabed geodiversity, were mostly absent from the literature, with only two publications found. Brazil in South America had many geodiversity assessments and European scholars have played crucial roles in the development of quantitative geodiversity assessment in recent years. Subsequent research will benefit from developing a unified geodiversity assessment approach, reaching a consensus on an accepted definition and standardising the geodiversity concept, broadening research site environment types and developing strategies to promote further international and intranational collaboration.

Biodiversity and ecosystem functions depend on environmental conditions and resources rather than the geodiversity of a tropical biodiversity hotspot

“… 10 ). To describe geodiversity, simple feature numbers were initially used but later, inspired by biology, replaced by metrics such as the Shannon diversity index 11 – 13 .…”

“…Using geodiversity as a surrogate for biodiversity burgeoned around the new millennium 13 , mainly to identify areas for conservation or natural heritage or to manage the exploitation of ecosystem services 12 , 14 – 16 . This endeavour was based on the hypothesis that specific geo-sites should support unique biota so that high geodiversity is coupled with high biodiversity 17 – 19 .…”

Towards Transferable Use of Terrain Ruggedness Component in the Geodiversity Index

“…They sometimes depend on the purpose of the study [14] or are neutral, and combine the widest range of the abiotic components [15]. Two widely used methods of geodiversity assessment [4,16]-which have also been modified for geodiversity evaluation on micro- [17], mid-and large-scale [18] study areas [17,19] or evaluation purposes [12,20,21]-are the one developed by Pereira et al [22], which equals the G value to the sum of geological, geomorphological, paleontological, pedological and mineral occurrence sub-indices, and the second one by Serrano and Ruiz-Flaño [3], which divides the multiplication of all geodiversity elements in an area and the terrain ruggedness index (R) of that area with the value of the natural logarithm of the area. The second method, which is to be discussed in greater detail in this article, has been extensively used and applied at various levels-ranging from local [23] to landscape [10] ones-and geographic environments, for example karst [17,24,25] and even the seabed [19], among others.…”

“…If the methods are standardized, site data can be put within larger-scale levels and contexts (a regional, landscape or global one) [47]. Similarly, such standardization procedures should be carried out in quantitative geodiversity assessment [16], since geodiversity evaluation has not adopted a unified approach [4]. Unfortunately, present geodiversity evaluation methods are set only for the aims of specific studies [16], which makes their data and results incomparable [50].…”

A Quantitative GIS and AHP Based Analysis for Geodiversity Assessment and Mapping

“…Qualitative methods (e.g., [8,[13][14][15][16][17][18][19]) are based on the knowledge and sensibility of an expert or a group of experts, and because of this are characterized by a high degree of subjectivity. Quantitative methods (e.g., [20][21][22][23][24][25][26][27][28][29]) calculate geodiversity by means of simple algorithms; the repeatability of the results and the relatively high objectivity make these methods highly preferred [30]. Even quantitative methods have their limitations: the choice of criteria and parameters is still subjective, and the quality or absence of the input data affects the entire calculation [11].…”