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This work analyses the statistical link between the number of fractures counted by the geologist on fixed-size samples and the crushed length, namely the part of the sample that is crushed, a characteristic of the rock strength which must also be considered. For each sample, the fractures are classified according to their angle with the sample axis and it becomes possible to calculate a new attribute introduced in this paper, the “directional concentration”, a measurement of the dispersion of the fractures in the angular domain. This attribute explains the statistical link between fracturing and crushing, which leads to their correlation analyzed as a non-stationary regionalized variable. It then becomes possible to define spatial domains where, locally, the fractures are more or less numerous than expected based on a regionalized regression model. Two data sets were studied; the results were analyzed and interpreted by geotechnicians.

This work concerns mineral deposits consisting of geological bodies whose metal grades have different characteristics in terms of distribution and variogram, which means that estimating grades by ordinary kriging may produce unrealistic spatial continuity. This paper proposes a method based on the indicators of the geological objects (hereafter called units) and their product with the metal grade. This is illustrated by an application to a porphyry copper deposit. The aim of this paper is essentially to promote the use of variogram ratios to analyze and characterize deposits.

This paper is concerned with the problem of predicting the surface elevation of the Bradenbreccia pipe at the El Teniente mine in Chile. This mine is one of the worlds largest andmost complex porphyry-copper ore systems. As the pipe surface constitutes the limit of thedeposit and the mining operation, predicting it accurately is important. The problem istackled by applying a geostatistical approach based on closed-form non-stationary covariancefunctions with locally varying anisotropy. This approach relies on the mild assumptionof local stationarity and involves a kernel-based experimental local variogram a weightedlocal least-squares method for the inference of local covariance parameters and a kernelsmoothing technique for knitting the local covariance parameters together for kriging purpose.According to the results, this non-stationary geostatistical method outperforms thetraditional stationary geostatistical method in terms of prediction and prediction uncertaintyaccuracies.

When several polyphagous herbivore species share a parasitoid, the tri-trophic interaction networks can be difficult to predict. In addition to direct effects, the parasitoid may influence the herbivore community by mediating indirect interactions among hosts. The plant species can also modulate the parasitoid preference for a specific host. One of the indirect effects is apparent competition, a negative interaction between individuals as a result of the action of shared natural enemies. Here, we focus on the interactions between the parasitoid Fopius arisanus (Braconidae) and two generalist fruit fly pests: Bactrocera dorsalis and Bactrocera zonata (Tephritidae). This parasitoid was introduced into La Reunion in 2003 to control populations of B. zonata and can also interact with B. dorsalis since its invasion in 2017. Our main objective is to characterize the tri-trophic interactions between F. arisanus, fruit fly and host plant species. We developed a long-term field database of fruit collected before and after the parasitoid introduction and after the B. dorsalis invasion in order to compare parasitism rate and fruit fly infestation for the different periods. In laboratory assays, we investigated how the combination of fruit fly species and fruit can influence the preference of F. arisanus. In the field, before the invasion of B. dorsalis, the parasitism rate of F. arisanus was low and had a little impact on the fruit fly infestation rate. After the B. dorsalis invasion, we observed an increase in parasitism rate from 5% to 17%. A bioassay showed that females of F. arisanus could discriminate between eggs of different fruit fly and host plant species. The host plant species preference changed in relation to the fruit fly species inoculated. Field observations and laboratory experiments suggest the possible existence of apparent competition between B. dorsalis and B. zonata via F. arisanus.

When several polyphagous herbivore species share a parasitoid, the tri-trophic interaction networks can be difficult to predict. In addition to direct effects, the parasitoid may influence the herbivore community by mediating indirect interactions among hosts. The plant species can also modulate the parasitoid preference for a specific host. One of the indirect effects is apparent competition, a negative interaction between individuals as a result of the action of shared natural enemies. Here, we focus on the interactions between the parasitoid Fopius arisanus (Braconidae) and two generalist fruit fly pests: Bactrocera dorsalis and Bactrocera zonata (Tephritidae). This parasitoid was introduced into La Reunion in 2003 to control populations of B. zonata and can also interact with B. dorsalis since its invasion in 2017. Our main objective is to characterize the tri-trophic interactions between F. arisanus, fruit fly and host plant species. We developed a long-term field database of fruit collected before and after the parasitoid introduction and after the B. dorsalis invasion in order to compare parasitism rate and fruit fly infestation for the different periods. In laboratory assays, we investigated how the combination of fruit fly species and fruit can influence the preference of F. arisanus. In the field, before the invasion of B. dorsalis, the parasitism rate of F. arisanus was low and had a little impact on the fruit fly infestation rate. After the B. dorsalis invasion, we observed an increase in parasitism rate from 5% to 17%. A bioassay showed that females of F. arisanus could discriminate between eggs of different fruit fly and host plant species. The host plant species preference changed in relation to the fruit fly species inoculated. Field observations and laboratory experiments suggest the possible existence of apparent competition between B. dorsalis and B. zonata via F. arisanus.

An edited, revised, and expanded version of a paper discussed at the World Society of Ekistics Symposium Defining Success of the City in the 21st Century in Berlin on Oct 24-28, 2001 is presented. Among other things, Antoine discusses the changing urban policies towards sustainability in the Mediterranean.

Serge Antoine, a high-ranking civil servant (Conseiller-Maître à la Courdes Comptes) who, among his other distinguished posts, has been responsible for international relations at the French Ministry of the Environment and originator of the Mediterranean Blue Plan, is President of the Claude Nicolas Ledoux Foundation for future-oriented studies, member of the board of the international association Futuribles, and member of the World Society for Ekistics (WSE). The text that follows is an edited, revised and expanded version of a paper presented at the WSE Symposion \"Defining Success of the City in the 21st Century\", Berlin, 24-28 October, 2001.

The three-stage \"Blue Plan\" for the Mediterranean area proposes a concerted approach to socioeconomic problems, and its aim is to evaluate different development possibilities and select those designed to safeguard the marine environment and the Mediterranean sea-board for present and future generations. It takes fresh initiatives for a multinational cooperation favorable to the transfer of knowledge and technology. The Blue Plan might be an indication of a new solidarity and an emerging Mediterranean consciousness.