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Sedimentary sequences in ancient or long-lived lakes can reach several thousands of meters in thickness and often provide an unrivalled perspective of the lake's regional climatic, environmental, and biological history. Over the last few years, deep-drilling projects in ancient lakes became increasingly multi- and interdisciplinary, as, among others, seismological, sedimentological, biogeochemical, climatic, environmental, paleontological, and evolutionary information can be obtained from sediment cores. However, these multi- and interdisciplinary projects pose several challenges. The scientists involved typically approach problems from different scientific perspectives and backgrounds, and setting up the program requires clear communication and the alignment of interests. One of the most challenging tasks, besides the actual drilling operation, is to link diverse datasets with varying resolution, data quality, and age uncertainties to answer interdisciplinary questions synthetically and coherently. These problems are especially relevant when secondary data, i.e., datasets obtained independently of the drilling operation, are incorporated in analyses. Nonetheless, the inclusion of secondary information, such as isotopic data from fossils found in outcrops or genetic data from extant species, may help to achieve synthetic answers. Recent technological and methodological advances in paleolimnology are likely to increase the possibilities of integrating secondary information. Some of the new approaches have started to revolutionize scientific drilling in ancient lakes, but at the same time, they also add a new layer of complexity to the generation and analysis of sediment-core data. The enhanced opportunities presented by new scientific approaches to study the paleolimnological history of these lakes, therefore, come at the expense of higher logistic, communication, and analytical efforts. Here we review types of data that can be obtained in ancient lake drilling projects and the analytical approaches that can be applied to empirically and statistically link diverse datasets to create an integrative perspective on geological and biological data. In doing so, we highlight strengths and potential weaknesses of new methods and analyses, and provide recommendations for future interdisciplinary deep-drilling projects

In the 1970s regional groundwater modelling began to be used in support of many hydrogeological investigations in the UK. A number of the studies were concerned with groundwater development at a regional scale in conjunctive use schemes; elsewhere the effect of pumping from aquifers on river flows or the ingress of saline water was considered. Due to the limited power of digital computers at that time, special numerical codes were often prepared for individual projects, with consequent inefficiency and inconsistency of practice. However, by the mid 1990s the need to formalize and standardize groundwater modelling projects was recognized. The Environment Agency of England and Wales prepared a strategy to manage and monitor the projects. A Template Project Brief was prepared to define the many tasks involved in groundwater studies and to clarify the roles of contractor and client (Environment Agency). In addition Guidance Notes were prepared to disseminate procedures and techniques that had resulted in successful outcomes. This paper summarizes some of the earlier studies, provides information about the Project Brief and Guidance Notes and illustrates some critical issues in groundwater modelling by reference to two case studies.

The number of groundwater specialists working in the UK or from a UK base is now estimated to significantly exceed 1000. This is at least a 60-fold increase over the 60 year period since the enactment of the legislation, in the form of the 1945 Water Act, that initiated a quantitative approach to groundwater management in the UK. Jack Ineson was the key initial influence in that process. Although the science that has been developed and the schemes and activities that have been undertaken over the period have been well documented, there has been no analysis in organizational and professional terms since the early 1990s. This review addresses that gap and attempts to assess critically, in the context of contemporary groundwater issues, what has been achieved by the profession in this period of rapid growth and how well it is equipped to deal with future challenges. Over the period not only has hydrogeology become a mainstream branch of the geosciences but groundwater studies have become recognized as a key component in the understanding and management of the natural environment. Many complementary disciplines in physical, biological and social science are now engaged in work on groundwater. The subject is much better understood both among policy makers and the general public, and its profile looks set to be raised with the heightened pressures from climate change on interactions between land and water.