**1. Introduction**

Coastal zones are amongst the most dynamic areas of the planet, where processes occurring in the atmosphere, hydrosphere, lithosphere and biosphere are endlessly interacting in a continually changing balance. For human beings, these balances are highly relevant, as the coasts are home to socio-cultural and economic processes vitally important to humankind [1]. Benefits provided by these systems drive their exploitation, often leading to severe degradation [2]. Such negative changes stimulated the need for coastal study and monitoring in recent years [3].

The reduction in space available for the natural functioning of coastal ecosystems, due to phenomena such as sea level rise and the construction of infrastructure, produces what is known as "coastal squeeze", which may lead to the disappearance of some species, ecosystems and, consequently, ecosystem services. According to Silva et al. [4], this phenomenon includes local, regional or global anthropogenic processes and favors negative consequences at different time scales that induce alterations in the natural dynamic of ecosystems and inhibit the capacity of ecosystems to adapt to climate change. Human actions are therefore one of the most important pressures faced by ecosystems [1].

The Drivers–Pressure–State–Impact–Response (DPSIR) framework [5] has been widely used to assess coastal squeeze. However, in 2016, Elliot et al. [6] reported that, since 1999, 25 schemes for management and decision making across ecosystems have used derivations of the DPSIR conceptual framework. Elliot et al. [6] recognized that clearer,

**Citation:** Abarca, S.C.; Chávez, V.; Silva, R.; Martínez, M.L.; Anfuso, G. Understanding the Dynamics of a Coastal Lagoon: Drivers, Exchanges, State of the Environment, Consequences and Responses. *Geosciences* **2021**, *11*, 301. https:// doi.org/10.3390/geosciences11080301

Academic Editors: Gianluigi Di Paola, Germán Rodríguez, Carmen M. Rosskopf and Jesus Martinez-Frias

Received: 21 May 2021 Accepted: 19 July 2021 Published: 21 July 2021

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**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

more comprehensive, nested conceptual models are needed to quantify the links between pressure–state change in marine and coastal ecosystems.

The Drivers, Exchanges, State of the Environment, Consequences and Responses (DESCR) framework is based on the Drivers–Pressure–State–Impact–Response (DPSIR) framework, which is considered a useful system for the organization and presentation of environmental sustainability factors [5]. DESCR is a variant of this methodology, in which, instead of analyzing the pressures, the bidirectional exchanges of fluxes of matter and energy with the environment are considered simultaneously, evaluating their natural dynamics and connectivity. These exchanges, in which the drivers modify the state of the environment and vice versa, are considered in this cycle, as suggested by [7]. This analysis of the exchanges reflects the intensity of the pressures that exist in the study area. The impacts are evaluated as consequences in the ecosystems and can be positive, negative or neutral [4]. This methodology was described in a study on coastal squeeze in Puerto Morelos, Mexico, as a tool to evaluate and manage the consequences of the phenomenon [4].

Over recent years, environmental management has developed considerably in Latin America, but problems associated with anthropic factors such as pollution, destruction and degradation of renewable natural resources and the environment are still all too common [8]. In the case of Mexico, the tourist boom of recent years [9] has left its mark. In the state of Veracruz, the coastline, ca. 745 km in length [10], is dotted with urban and touristic developments and is of great importance ecologically, socially and economically [9]. In particular, the coastal lagoon of La Mancha (Figure 1), in the state of Veracruz, belongs to the municipality of Actopan. The lagoon has been on the Ramsar List of Wetlands of International Importance since 2004 [11] and was also established as a Priority Mangrove Conservation Site by CONABIO, the National Commission for the Knowledge and Use of Biodiversity [12]. Tourism in the vicinity of La Mancha is managed by a sustainable ecotourism company, called *La Mancha en Movimiento S.S.S.*, where local fishermen, housewives, farmers and others have been trained to work as eco-guides [13].

It is important to identify, describe and analyze the anthropic and natural actions that regulate the lagoon ecosystem of La Mancha, in order to understand the conservation status of this environment and subsequently generate viable responses to manage it in a sustainable way. To explain the development and evolution of the coastal ecosystems of the area around La Mancha, a literature review was carried out, analyzing physical and environmental characteristics of the area, impacts of anthropic activities and consequences of the pressures on the lagoon, dune and mangrove ecosystems in the area, according to the DESCR framework. The characteristics of the lagoon and associated ecosystems were analyzed from a qualitative perspective. This approach could be used as a basis to outline policies for the sound management and use of this area.
