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Understanding the dynamics of species invasions in aquatic ecosystems is crucial for conservation and management efforts. We investigated the influence of species interactions and habitat complexity on biotic resistance to invasion by small-bodied freshwater fishes in peninsular Florida. Specifically, we focused on the interactions between two native species, Florida bass (Micropterus salmoides) and eastern mosquitofish (Gambusia holbrooki), and a common invader, the green swordtail (Xiphophorus hellerii). Our experiments included tanks with varying levels of structural complexity to mimic different habitat types. The presence of both native species significantly reduced swordtail survival, but the effect varied depending on habitat complexity. In habitats with strong predation refuge, mosquitofish facilitated bass predation on swordtails, whereas in habitats with weak predation refuge, bass suppressed mosquitofish aggression, leading to interference. Mosquitofish predominantly occupied vegetated areas and aggressively interacted with swordtails, significantly reducing invader survival. Our findings highlight the importance of considering species interactions and habitat complexity in predicting biotic resistance to invasions. We conclude that diverse interactions among native species can either enhance or impede invasion resistance, with implications for conservation and management strategies. Further research is needed to understand the broader impacts of multiple predators and competitors on invader dynamics in aquatic ecosystems.

The concept of adaptive capacity has received significant attention within social-ecological and environmental change research. Within both the resilience and vulnerability literatures specifically, adaptive capacity has emerged as a fundamental concept for assessing the ability of social-ecological systems to adapt to environmental change. Although methods and indicators used to evaluate adaptive capacity are broad, the focus of existing scholarship has predominately been at the individual- and household- levels. However, the capacities necessary for humans to adapt to global environmental change are often a function of individual and societal characteristics, as well as cumulative and emergent capacities across communities and jurisdictions. In this paper, we apply a systematic literature review and co-citation analysis to investigate empirical research on adaptive capacity that focus on societal levels beyond the household. Our review demonstrates that assessments of adaptive capacity at higher societal levels are increasing in frequency, yet vary widely in approach, framing, and results; analyses focus on adaptive capacity at many different levels (e.g. community, municipality, global region), geographic locations, and cover multiple types of disturbances and their impacts across sectors. We also found that there are considerable challenges with regard to the ‘fit’ between data collected and analytical methods used in adequately capturing the cross-scale and cross-level determinants of adaptive capacity. Current approaches to assessing adaptive capacity at societal levels beyond the household tend to simply aggregate individual- or household-level data, which we argue oversimplifies and ignores the inherent interactions within and across societal levels of decision-making that shape the capacity of humans to adapt to environmental change across multiple scales. In order for future adaptive capacity research to be more practice-oriented and effectively guide policy, there is a need to develop indicators and assessments that are matched with the levels of potential policy applications.

Abstract Social networks are not just patterns of interaction and sentiment in the real world; they are also cognitive (re)constructions of social relations, some real, some imagined. Focusing on networks as mental entities, our essay describes a new method that relies on stylized network images to gather quantitative data on how people “see” specific aspects of their social worlds. We discuss the logic of our approach, present several examples of “visual network scales,” discuss some preliminary findings, and identify some of the problems and prospects in this nascent line of work on the phenomenology of social networks.

The purpose of this chapter is to provide an overview of the field of social network analysis (SNA), including both theory and method, as applied to the understanding of organizations. It starts with a discussion of fundamental concepts of SNA. Examples of network concepts at dyadic level, node‐level and group or whole network level of analysis are tabulated, along with thumbnail accounts of sample research in both the network and theory of networks domains. The chapter ends with a discussion of the methodological tools and challenges. Two major strategies including full network analysis and ego network approach, for studying social networks have been elaborated. A best practice in network research methodology is called the ethnographic sandwich. The ethnographic sandwich refers to sandwiching a formal, quantitative network study in between two layers of ethnographic work: one at the beginning of the study and one at the end of the study.