They define Adaptive Monitoring like this:
A monitoring program in which the development of conceptual models, question setting, experimental design, data collection, data analysis, and data interpretation are linked as iterative steps. An adaptive monitoring program is one that can evolve in response to new questions, new information, situations or conditions, or the development of new protocols but this must not distort or breach the integrity of the data record. The adaptive monitoring approach can be applied to all kinds of monitoring including question-driven, passive and mandated monitoring programs.So models, questions, etc etc all linked into iterative steps, with the ability to evolve in response to new questions, information or conditions. Why isn't it Adaptive Management? Well, it doesn't directly involve decision making about anything other than the monitoring plan itself, at least on the surface, so that rules out Decision Theoretic AM. They claim that experimentation isn't required, which would rule out Experimental-Resilience AM. However, one of the three things they claim needs to be done to make Adaptive Monitoring is to build partnerships with ... wait for it ... policy makers. In other words, it is meant to influence decision making.
What I find interesting is that both of their case studies involve monitoring plots in different "treatments", which makes them suspiciously experimental sounding. In addition, in both case studies there are management decisions being made on the basis of the results of the monitoring, so I would suggest that the difference between AManagement and AMonitoring is a question of badging and marketing, rather than fundamental differences. Both case studies would benefit enormously from a decision theoretic approach to the whole management system, rather than a narrow focus on monitoring.