Valuation of Ecosystem Services of Fluvial Beaches in the Southeastern Peruvian Amazon

Abstract

Riverine beaches in the Amazon are valuable ecosystems for local populations, providing areas for recreation and classic beach activities. However, these ecosystems are subject to multiple pressures. The study presents the results of the willingness to pay (WTP) of 518 respondents at two beaches (Hawaii and Bora Bora) in the Peruvian Amazon (Puerto Maldonado, Madre de Dios). Over 58% of respondents indicated that they would use DAP to maintain beach ecosystem services (BES) beyond recreational use. The amount of payment was an average WTP value of USD 1.41/person/visit for Hawaii and USD 1.34/person/visit for Bora Bora. While factors related to environmental perception had a decisive influence, WTP at beaches was independent of economic factors such as income. The results can support decision-makers with quantitative data on social preferences regarding beach improvement policies in the southeastern Peruvian Amazon.

1. Introduction

The importance of ecosystem services has evolved to become a fundamental aspect of wilderness management [1,2]. The Amazon’s freshwater ecosystems, from wetlands to lakes, lagoons, swamps, rivers, estuaries, and streams, among others, have in common the presence of a permanent or temporary body of water. These ecosystems cover an area of approximately one million square kilometers and play an essential role in climate regulation, nutrient transport, water quality, biodiversity support, recreation, and food production, benefiting local, regional, and global communities [1,2]. Compared to other ecosystems, the biodiversity of these freshwater systems is disproportionately high, but the surface area of these systems is less than 1% of the planet [1]. The frequent proximity of freshwater ecosystems to human population centers has made these areas attractive for visitation. However, the impact of activities in these areas is intense [1,3,4].

Freshwater biodiversity is affected not only in the Amazon ecosystem but globally, due to a number of factors that threaten its continuity. The reasons for the decline of freshwater biodiversity are many, but the most important threats are habitat degradation, pollution, alteration of water flows and extraction, overfishing, and the introduction of exotic species; factors that will be exacerbated by the effects of climate change. All of these human-induced actions are not permanent and will eventually affect human well-being. This is due to the intimate link between human livelihoods and freshwater biodiversity as a basic service; water-related services that support the health, livelihoods, and well-being of people, taking into account the needs of Indigenous and local communities, as well as people in situations of poverty and vulnerability [1,5].

In particular, coastal and inland beaches are under severe pressure as components of freshwater ecosystems; they are viewed as ecosystems that offer advantages that are directly related to tourism, aesthetics, and recreation [1,6]. Beaches provide a range of ecosystem services that benefit society and are essential for human use. This is because beaches are strongly influenced by and interact physically and biologically with freshwater systems [1,6]. This means that sandy beach systems play an important role in the global land–freshwater interface [1,7]. When discussing impacts on the dynamic ecosystems of freshwater beaches and their associated goods and services, it is important to consider the potential impacts on adjacent habitats, both physical and ecological [1,7].

Over the years, economic valuation techniques have focused on people’s preferences in real markets. However, for natural resources and environmental goods (such as scenic and recreational beauty), there was no defined market to determine consumer preferences and willingness to pay [1,7]. Contingent valuation research conducted in aquatic ecosystems in Latin America and the Amazon focused on obtaining income for recreational values and environmental services, social benefits, and public policy implementation. Similarly, consumer economic behavior is measured by the responses obtained for the range of prices set, as well as the variation in willingness to pay for socioeconomic and environmental variables in the surveys [1,7]. This direct valuation process facilitates the identification of the preferences expressed by current or potential visitors, as well as the evaluation of the maximum willingness to pay (WTP) to prevent the degradation of environmental quality in the Amazonian aquatic ecosystems [1,7].

Recognizing the value of beach ecosystem services and how they may be affected, studies have been carried out to determine how bathers value these ecosystems [4]. This refers to willingness to pay (WTP) studies, as they facilitate the identification of environmental preferences and are often used in public environmental projects [1,8]. In order to provide relevant information on possible solutions to the progressive degradation of beach ecosystems, these studies used the contingent valuation method to estimate the WTP for the beach ecosystem service. WTP can be calculated using revealed preferences [1,9], which determine WTP by dividing individual payments to consume a resource or by analyzing stated preferences (economic value through a hypothetical market) and asking respondents to report their WTP directly [1,9,10,11].

Many studies analyze differences in spatial heterogeneity using the Contingent Valuation Method (CVM) [1,12] as well as directly identifying ideal market scenarios through field studies to assess visitor satisfaction and improve ecosystem services [1,11,12]. Despite its widespread use, the contingent valuation method has some limitations, such as the deviation from the starting point, which presents a hypothetical scenario and does not ensure that respondents really answer the following questions [13]. In general terms, several methodological caveats have been identified. However, experts in the field have noted that the results of properly conducted processes approximate reality [11].

Despite the favorable context for the use of VCMs in the valuation of ecological services, studies on freshwater or inland beaches are scarce, as most of them refer to coastal or marine areas, such as water treatment plants [1,14,15,16], for beach restoration [1,17], and its application in tourism services [1,16,18].

The economic, recreational, aesthetic, and cultural aspects of beaches make them a desirable resource [1,19], but human activities are always putting pressure on them. This is the case of the freshwater beaches of the Peruvian Amazon, where there are several problems related to water pollution [20] and the quality of sand and silt on beaches [21,22,23,24]. There is no history of studies on WTP in freshwater beach ecosystems in the southern Peruvian Amazon, but there are private beaches that charge for access and maintenance services, without any methodological basis for estimation. Therefore, here we present an alternative view by investigating the WTP of visitors for ecosystem services in two free access river beaches (Bora Bora and Hawaii) in the city of Puerto Maldonado, Tambopata, Madre de Dios–Peru. We address the following research questions: (1) What are the descriptive characteristics of the river beaches? (2) Which socio-economic variables influence the WTP for the ecosystem services of the river beaches? (3) What is the WTP for the ecosystem services of the river beaches using the Contingent Valuation Method (CVM)? (4) What is the average value of the WTP for the ecosystem services of the river beaches?

2. Materials and Methods

2.1. Study Area

In the southeast of the Peruvian Amazon lies the department of Madre de Dios. It borders Puno to the south, Cusco to the west, and Ucayali to the north, and internationally with Brazil and Bolivia. It has an area of about 85,000 km² and a population of about 141,000 inhabitants [25].

The study areas were the river beaches of Bora Bora and Hawaii, located on the outskirts of the city of Puerto Maldonado, which has an area of 16.61 km² and a population of 85,024 inhabitants [25]. Puerto Maldonado lies between the Madre de Dios and Tambopata rivers. It is geographically located between the coordinates 12°38′49″–12°32′56″ south latitude and 69°11′40″–69°13′40″ west longitude, with an average altitude of 201 m above sea level [25].

The climate is hot and humid, the hottest months being August and September, with annual rainfall of more than 2000 mm and an average temperature of 26°. The dry season is from June to August, with the heaviest rainfall from October to April. The surazo or friaje is caused by cold polar winds from the south, with temperatures dropping to an average of 8 °C for several days [25,26,27].

Bora Bora Beach is located on the left bank of the Madre de Dios River, in the area of El Triunfo, 3.5 km from the center of the city of Puerto Maldonado (Figure 1). The access road is terrestrial and the entrance to the beach is free and has a nice view of the Continental Bridge. Hawaii Beach is located on the right bank of the Tambopata River, in front of the Tambopata Port in Puerto Maldonado, 2.2 km from the center of the city of Puerto Maldonado. Access is by boat, usually on Saturdays and Sundays throughout the day. On these beaches, you can enjoy beautiful landscapes at sunset. These beaches were chosen because they are places that the population can access without payment restrictions. Evaluations to determine how much visitors are willing to pay for services at Bora Bora and Hawaii beaches in Puerto Maldonado were conducted in 2021.

2.2. Beach Characterization

Seasonal visits were made to river beaches during the months of June through August, according to [1] and adapted by [28]. A technical inspection was carried out in the study area to establish a baseline since there is little scientific and official information about the two beaches. In this field inspection, the characteristics of the beaches were described in detail. For this purpose, information was collected on the generalities, uses, and activities of the beach, its environmental characteristics, the pollution present, the services and facilities available, and the use of the space [1].

2.3. Contingent Valuation and Willingness to Pay

The study proposes the use of the Contingent Valuation Method (CVM), which determines the monetary value of a good or service without a market [1,29,30,31,32,33,34].

WTP was projected by means of a question to accept or not (simple bounded dichotomous format) a random amount for the maintenance of beach ecosystem services [29,30,31,32,33,35]. The surveys simulated the hypothetical scenario that the resident will face while making a decision on whether or not to purchase a certain good in the market: “The river beaches of Bora Bora and Hawaii, surrounding the city of Puerto Maldonado, provide adequate conditions of quality of use and permanent maintenance of ecosystem services by the competent authority that guarantee the safety of visitors”.

To reduce the hypothetical bias, it was considered that the construction of the hypothetical market should accurately reflect the ecosystem service of river beaches. To this end, all support was provided to clearly define and explain the environmental good or service, as well as the specific characteristics of the change in BES. Also, they were provided with the mechanism or method of collection (WTP) in the form of public services managed by local governments [1,34,36].

Based on previous DAP studies [1,34,36], a survey was designed to determine the willingness to pay of visitors to the two selected river beaches. Structure of the survey questionnaire for the contingent valuation (CV) study [1,34,36], was structured in three pieces for the current study: the first section collected socioeconomic data from visitors, including standard questions about gender, age, occupation, education level, monthly income, frequency of visits, interest in ecology and environmental issues, satisfaction, and the time cost of beach access. Second, it included Beach Ecosystem Services (BES), including the importance of BES and preservation of BES for future generations; and finally, questions related to WTP, hypothetical prices obtained in the pilot survey (15% of respondents in the final sample), considered open-ended questions to visitors by WTP. The hypothetical or starting price values with the highest frequencies were assigned to the final survey for Hawaii (USD 0.26, USD 0.79, USD 1.32, and USD 1.84) and Bora Bora (USD 0.26, USD 0.79, and USD 1.32), where the surveys were distributed with specifications of the maximum amount to be paid. The survey has been validated by experts [10,11,37,38].

Specific questions concerning beach usage were posed to the BES, including how frequently people visit the beaches each month, what their primary activities are, and how satisfied they are with the beaches.

Following the experience of beach ecosystem valuation [4], respondents were given an explanation of the many types of ecosystem services and examples of each type. In this case, the following topics were covered: (i) the importance of each BES category; and (ii) the respondents’ desire to conserve BES. The criteria ranged from not very interested to very interested, and high, medium, and low values for preserving BES for future generations were formed to classify the importance of BES (provisioning, regulating, supporting, and cultural).

“Would you be willing to pay for the preservation of the ecological services of the beach?” was the proposed WTP. An open-ended survey was used to determine WTP values for payments per visit, and a final survey was used to determine payment ranges. Socio-economic criteria for the WTP analysis of BES maintenance were discovered through the survey. In this regard, the CVM has been used extensively around the world to determine user WTP for maintaining the benefits associated with river beaches [1,13,29,34,36,39,40].

A total of 518 surveys (Bora Bora (190 visitors surveyed) and Hawaii (328 visitors surveyed)) were conducted, with a margin of error of approximately 5% and a confidence level of 95%. Based on the hypothetical prices obtained, a simple random probability sample was taken, where everyone had an equal chance of participating and being selected for the study. For this purpose, visitors who were 18 years of age or older and able to pay were considered. In the case of Bora Bora beach, according to visitors and local residents, an average of 1600 visitors/month is estimated. In the case of Hawaii beach, 9600 visitors/month.

2.4. Statistical Analysis

Data were extracted and compiled from a comprehensive questionnaire administered between June and August 2021. For the statistical data analysis, descriptive and inferential techniques, as well as the Chi-square test, were used. Additionally, a binary logistic regression (logit, Equation (1)) model was employed to identify the various factors that may have a significant impact on visitors’ WTP (Willingness to Pay) for the beaches. All statistical analysis were made using STATA software (version 18).

$$Pi=P(Z_i\le X_i\beta =F\left(X_i\beta \right)={\displaystyle \frac{e^{X_i\beta }}{1+e^{X_i\beta }}}$$

(1)

where Pi = it is the probability that the dependent variable equals one, so β is the change in the probability that P = 1 is associated with a unit change in x_i, holding the other explanatory variables constant.

The likelihood function was expressed as follows:

$$\mathrm{Log\; L}=\sum _i^n{Y}_i(X_i\beta )-\sum _i^n\mathrm{l}\mathrm{o}\mathrm{g}(1+e^{X_i\beta })$$

(2)

To determine the marginal effects of changes in the regressor variables on the conditional probability, models based on the derivatives of the probability with respect to a given explanatory variable were used (Equations (3) and (4)).

$${\displaystyle \frac{\partial Pi}{\partial xij}}\equiv {\displaystyle \frac{\partial }{\partial xij}}P\left(yi={\displaystyle \frac{1}{xi}}\right)={\beta }_j ·f(x_j{\beta }_j)$$

(3)

where f(z) is the corresponding density function (Equation (4)).

$${\displaystyle \frac{\partial Pi}{\partial xij}}={\displaystyle \frac{\partial }{\partial xij}}P\left(yi={\displaystyle \frac{1}{xi}}\right)={\beta }_j · {\displaystyle \frac{e^{X_i\beta }}{{(1+e^{X_i\beta })}^2}}$$

(4)

The following equation was used to calculate the marginal effects for the mean value of the explanatory variables (Equation (5)).

$$n^{-1}\sum _{i=1}^{n}f\left(x_j{\beta }_j\right)\beta ó f\left({\overline{x}}_j{\beta }_j\right)\beta$$

(5)

Taking into account previous studies such as [1,41], binary regression analysis was used to explain how socioeconomic variables influenced participants’ willingness-to-pay responses to yes/no questions (dichotomous outcome).

Three models were evaluated according to the level of significance of the socioeconomic variables, total, 10% and 5%. It was decided to use a model with a 10% significance level (0.10) to include more variables. In the Hawaii study, the variables hypothetical price (hp), interest in environmental issues (ica), and frequency of visits (fv) were included. In the Bora Bora study, the variables hypothetical price (hp) and time cost to access the beach (ctaevu) were used.

The following equation was used to determine the probability of answering yes for WTP for the maintenance of beach ecosystem services [42,43,44,45,46] (Equation (6)).

$$Prob\left(yes\right)={\beta }_0-{\beta }_1\left(WTP\right)+\sum {\beta }_i{Z}_i$$

(6)

where Prob(yes) is the parametric method for estimating WTP using logit regression; where the dependent variable is beachgoers who say “yes” to paying or “no” to paying the bid level.

The WTP for the maintenance of beach ecosystem services in this type of model was:

$$WTP={\displaystyle \frac{{\widehat{\beta }}_0\sum _2^n{\widehat{\beta }}_i{Z}_i}{{\widehat{\beta }}_1}}$$

(7)

The parametric estimation of the minimum WTP was carried out using the logit model, which mathematical representation of the probability (P_k) of accepting a payment for the maintenance of beach ecosystem services is as follows:

$$P_k=E\left(Y={\displaystyle \frac{1}{X_k}}\right)={\displaystyle \frac{1}{1+{ e}^{-({\widehat{\beta }}_0+{\widehat{\beta }}_1{X}_1+\dots +{\widehat{\beta }}_k{X}_k)}}}$$

(8)

where, Y = 1 if the answer is affirmative (yes) and Y = 0 if the answer is negative (no), with respect to the willingness to accept a minimum compensation, and X_k represents the set of socioeconomic and cultural variables characteristic of the survey.

The criteria used to evaluate the variables were as follows: Sex (male, female); Age (18–35, 36–55, >55); Level of education (no education, primary school, high school or bachelor’s degree); Interest in environmental issues (low, medium, high); Income (<252.63 USD, 252.89 USD to 526.32 USD, 526.58 USD to 921.05 USD, 921.32 USD to 1315.79 USD, >1315.79 USD); Frequency of visits (biannual, monthly, bi-weekly, weekly); Satisfaction (very dissatisfied, dissatisfied, satisfied, very satisfied); Access time (60 min, 30–60 min, 15–30 min).

To ensure the validity of the results, a variance inflation factor (VIF) was used to control for multicollinearity. Hawaii beach reported VIF values for the variables; income with 1.32, education level with 1.23, frequency of visits with 1.13, gender with 1.11, satisfaction with 1.08, age with 1.07, interest in environmental issues with 1.07, time of access to the beach with 1.06, and hypothetical price with 1.05. For Bora Bora beach, it was income with 1.71, education level with 1.142, frequency of visits with 1.24, gender with 1.34, satisfaction with 1.05, age with 1.12, interest in environmental issues with 1.10, time of access to the beach with 1.04, and hypothetical price with 1.11. In each case, they have a low correlation and do not need to be tested [47].

3. Results

3.1. River Beach Characterization

The beaches of Hawaii and Bora Bora cover approximately 5.37 ha and 6.38 ha, respectively; both, however, lack infrastructure and services. During the visits, we observed pollution, especially litter and waste on the beach, with no specific regulation, except for sewage. However, the environmental characteristics are still acceptable for recreational use (

Table 1. Beach characterization.

Beach Characterization		Hawaii	Bora Bora
Infrastructure and services	Beach access	Limited access	Good access
	Road conditions	Good access	Good access
	Type of transport	Private	Private
	Parking areas	Absence	Presence (not zoned)
	Public toilets	Absence	Absence
	Waste bins	Absence	Absence
	Lifeguard	Absence	Absence
	Control and monitoring	Absence	Absence
	Beach activities	Enjoy sunbathing and swimming	Enjoy sunbathing and swimming
	Recreational and sports equipment (sports grounds)	Absence	Absence
	Trading	Presence (Unorganized)	Presence (Unorganized)
	Motor vehicles on the beach	Absence	Absence
	Equipment (umbrellas, chairs)	Presence	Presence
	Signage–Public information	Absence	Absence
Contamination	Odors	Seasonal Only	Seasonal Only
	Waste	Seasonal Only	Seasonal Only
	Waste piles	Seasonal Only	Seasonal Only
	Discharges or discharges to the river (Wastewater/domestic)	Absence	Absence
Environmental characteristics	Beach area	>100 m	>100 m
	Beach shape	Straight	Straight
	Beach width	>100 m	>100 m
	Beach particles	Sand	Sand
	Sand color	Gray	Gray
	Sand grain type	Medium sand	Medium sand
	Type of swell	Waters with currents	Waters with currents
	Mouths	Absence	Absence
	Turbidity	Clear	Clear

). Despite the abandonment and lack of regulation by the competent authority, it is necessary that the authority develops beach conservation plans through immediate public policies to avoid the deterioration of ecosystem services due to seasonal pollution.

On the other hand, it is important to mention that the influx of visitors to private beaches is mainly due to the adequate environmental conditions they offer for recreation and rest. In this context of use and challenges related to infrastructure and services, pollution, as well as the conditions of free access to river beaches, present similarities with other regions worldwide; therefore, the presence of the minimum environmental conditions that offer recreational enjoyment and rest perceived by visitors are sufficient for their access, as researchers have found in different areas of the world [17,39,41,48,49,50,51].

3.2. Visitor/Bather Perception

According to the data obtained, the sampled population is local, which is common in the river beaches of the Peruvian Amazon. According to surveys of locals and visitors to the beaches, it is estimated that Bora Bora has an average of 1600 visitors/month during the dry season, while Hawaii has 9600 visitors/month.

The results showed that the highest percentage of respondents at the beaches studied were women between the ages of 18 and 35. The main educational level of visitors to Hawaii and Bora Bora was primary school, with 50% and 59%, respectively. Interest in environmental issues was generally high. The majority of visitors were employed, with salaries ranging from USD 252.81 to USD 526.32. Bora Bora had visitors with the highest and lowest purchasing power; 1.1% of respondents reported incomes above USD 1315.79, while 28.1% of respondents reported incomes between USD 0 and USD 252.63 (

Table 2. Descriptive metrics of socioeconomic characteristics affecting river beach ecosystem services.

Beach	Sex	Age	Education Level	Interest in Environmental Issues	Income	Frequency of Visits	Satisfaction	Access Time	Hypothetical Price
Hawaii (n = 328)
Category	Woman	18–35	Primary	High	252.89 US$ to 526.32 US$	Semi-annual	Satisfied	60 min	0.26 US$
Frequency	178	146	164	217	204	161	178	317	66
Percentage	27.8%	44.51%	50%	66.16%	62.20%	49.08%	54.27%	96.64%	20.12%
Bora Bora (n = 190)
Category	Woman	18–35	Primary	High	<252.63 US$	Semi-annual	Satisfied	60 min	0.26 US$
Frequency	130	111	112	101	103	112	126	180	45
Percentage	68.4%	58.4%	59.0%	53.2%	54.2%	59.0%	66.3%	94.7%	39.8%

Notes: Variables: Sex (female and male); Age (18 to 35, 36 to 55, and >55); Level of education (no education, primary school, high school or bachelor’s degree); Interest in environmental issues (low, medium, high); Income (<252.63 USD, 252.89 USD to 526.32 USD, 526.58 USD to 921.05 USD, 921.32 USD to 1315.79 USD, >1315.79 USD); Frequency of visits (biannual, monthly, bi-weekly, weekly); Satisfaction (very dissatisfied, dissatisfied, satisfied, very satisfied); Access time (15 to 30 min, 30 to 60 min and 60 min).

).

Most visitors visit the beaches on a monthly and semi-annual basis, primarily for recreational reasons. Visitors report varying degrees of satisfaction with beach use, with Hawaii reporting the highest satisfaction (54%) compared to Bora Bora (32%) (Table 2).

Regarding the entry price (hp) obtained in the pilot survey and used in the final survey, in both beaches; Hawaii (USD 0.26, USD 0.79, USD 1.32, and USD 1.84) and Bora Bora (USD 0.26, USD 0.79, and USD 1.32) opted for the lowest price (S/1.00), with a positive response of 20.1% and 39.5%, respectively. This confirms the economic theory of consumption in terms of tastes and preferences.

Cultural services were the most important (77%), followed by provisioning services (77%), support services (76%), and regulatory services (74%). It should be noted that the services ranked as most important differed between the two beaches. In Hawaii, support and cultural services were most important, while in Bora Bora, cultural and regulatory services were most important. At the level of importance for their maintenance, Hawaii and Bora Bora presented mostly medium values (interested) of BES, with priority given to support services for Hawaii and cultural services for Bora Bora.

3.3. Willingness to Pay for River Beach Ecosystem Services

Before proceeding with the econometric analysis, we verified that the hp variable met the assumptions of the dichotomous logit model using the contingent valuation method (CVM). In our case, the coefficient β of hp for both beaches was negative.

The logit model considered (p < 0.10) of the willingness to pay (WTP) for ecosystem services; Hawaii beach presents a logit model coefficient (R²) of 0.17, while Bora Bora has 0.14, which suggests an adequate model to classify individuals, a situation consistent with the principles of demand. As for the LR chi²(3) test, it is assumed that the null hypothesis that no variable infers WTP is rejected (LR chi²(3) =0 for Hawaii and LR chi²(2) =0 for Bora Bora). Overall, the logistic trend shows that the response rate decreases as the level of the WTP offer increases, which is consistent with demand-side principles.

For the Hawaii beach, hp had a negative impact per unit change as the price increased, so the probability of visitors paying for the ecosystem service decreased by 1.31 times and 7% on WTP. Factors such as frequency of visits (fv) and interest in environmental issues (ica) were positive and significant (p < 0.05), suggesting that these factors positively influenced WTP (

Table 3. Descriptive metrics of socioeconomic characteristics affecting river beach ecosystem services.

Hawaii Beach Variables	Coefficients	Standard Error	z	p-Value	Odds Ratio	Marginal Effect (dy/dx)
hp	−0.27	0.06	−4.85	0.00	0.76	−0.07
fv	0.29	0.14	2.06	0.04	1.34	0.07
ica	0.56	0.24	2.34	0.02	1.75	0.14
_cons	−0.54	0.72	−0.76	0.45
LR chi2(3)	30.95
Pseudo R2	0.17
Bora Bora Beach Variables	Coefficients	Standard Error	z	p-Value	Odds Ratio	Marginal Effect (dy/dx)
hp	−0.21	0.09	−2.25	0.02	0.81	−0.05
ctaevu	1.65	0.92	1.79	0.07	5.20	0.39
_cons	−0.70	0.97	−0.72	0.47
LR chi2(2)	11.30
Pseudo R2	0.14

Notes: Sex (sex), age (age), education level (edu), interest in environmental issues (ica), income (ing), frequency of visits (fv), access time (ctaevu), and hypothetical price (hp).

). The variable fv contributes 1.34 times to the occurrence of the event, while at the marginal effects level, a higher frequency of visits increases the probability of WTP by 7%. As for ica, it contributes 1.75 times to the occurrence of the event, while at the marginal effects level, a greater interest in environmental issues increases the probability of WTP by 14%.

As for the beach of Bora Bora, hp negatively influences the unit change as the price increases; consequently, the visitor’s probability of paying for the ecosystem service decreases by 1.24 times and the willingness to pay by 5%. While ctaevu was positive and significant (p < 0.05), indicating that this variable positively influences WTP (Table 3). The variable ctaevu contributes 5.20 times to the occurrence of the event, while at the marginal effects level, a shorter beach access time increases the probability of WTP by 39%.

In both beaches, whose access is free, curiously, the variables income, age, level of education, or sex were not determinant in the WTP. For the inhabitants of the city of Puerto Maldonado, Bora Bora beach is more distant, located on the northeast side of the city, crossing one of the longest bridges in Peru (continental) over the Madre de Dios River, so the cost of time to access the beach is fundamental in the WTP decision for the ecosystem service. In contrast, at Hawaii Beach, located close to the city on the banks of the Tambopata River, visitors are more interested in environmental issues, which is reflected in the frequency of visits for personal or family recreation purposes, which drives the WTP. Visitor demand is reflected in an average of 9600 visits per month at Hawaii Beach and 1600 visits per month at Bora Bora.

The predictive ability of the model based on the final survey data from Hawaii Beach adequately determined the membership of 148 people in group D (WTP) and 88 in group ~D (no WTP). Conversely, 43 people did not accept WTP when they actually did, while 49 people did not accept WTP. The probability of predicting people’s WTP for the beach was 77.5%, while the opposite was 35.8%. The overall goodness of fit of the model was 60.06%. Regarding the beach of Bora Bora, the model determined that 85 people belonged to group D (WTP) and 48 to group ~D (no WTP). Conversely, 28 people did not accept the WTP when in fact they did, and 29 people did not accept the WTP. The probability of predicting people’s WTP for the beach was 75.2%, while the opposite was 37.7%. The overall goodness of fit of the model is 60%.

Overall, WTP (+) predominated among visitors to the two river beaches, with 58.2% at Hawaii and 59.5% at Bora Bora. Descriptive statistical analysis was conducted by beach to determine the value visitors were willing to pay (

Table 4. Estimated WTP payable at each beach (per revenue—USD).

Variable	Observations	Mean	Standard Deviation	Minimum	Maximum
Hawaii Beach
WTP	328	1.41	0.35	0.58	2.24
Bora Bora Beach
WTP	190	1.34	0.76	1.17	5.25

). The analysis revealed an average WTP of USD 1.41/person/visit, slightly higher than Bora Bora beach with a WTP of USD 1.34/person/visit.

4. Discussion

4.1. River Beach Characterization

Information on the contingent valuation of river beaches in the Amazon is scarce compared to coastal beaches or lakes. Several studies have investigated the possible factors influencing the economic valuation of river beaches [5,17,19,28,40,41,52]. The analysis of beaches with different natural characteristics, pollution problems, and services allows us to understand the elements that influence the use and enjoyment of the beach. The results of the study (Table 1) suggest that the two beaches analyzed have similarities and some slight differences. To highlight one aspect, both beaches are long and have low turbidity (clear water). The favorable environmental conditions have a positive impact on activities such as beach soccer, volleyball, swimming, and sunbathing. However, the fact that they are open to the public without government control means that there is often chaos and pollution due to the accumulation of rubbish at the end of the day [53,54,55,56].

4.2. Visitor/Bather Perception

The conservation of marine and riverine beaches has been debated to varying degrees in the literature [1,14,41,50,52,57]. The consensus is that, in general, beaches are vulnerable to man-made elements and climate variability [58]. Long-term droughts, floods, water scarcity, decreased soil productivity, agricultural yields, disease outbreaks, invasion of alien species, water levels, decreased mangrove and reed cover, biodiversity status, and water purity are some of the ecological indicators that indicate that the beach ecosystem is in danger. In the case of the Amazon, what is usually mentioned is the progress of deforestation and the increase in activities that threaten the sustainability of natural resources.

The Madre de Dios and Tambopata Rivers are two of the most important watercourses in the Madre de Dios region, essential for the development of forestry, fishing, and agricultural activities. The current situation shows that population pressure, reduced land-use capacity, and contamination of fisheries by agricultural and gold mining activities are forcing the local population to seek other alternatives, accelerating the degradation of the beach ecosystem. This phenomenon is also observed in other areas with freshwater beaches [51,59,60].

Different people expressed different perceptions of WTP for the Hawaii and Bora Bora beaches. These different perceptions were associated with marginal utility derived from the preserved river ecosystem, and the results were manifested in WTP responses and quantities by significant variables (p < 0.10).

During the study period, an unfavorable interaction was identified in relation to beach pollution, where visitors exert a negative influence that would lead to ecosystem degradation due to a lack of attention to sustainability in their recreational activities. This attitude indicates a willingness to engage in beach recreation regardless of the environment. These findings are consistent with those of other studies conducted in similar contexts [53,54,55,56].

Visitors clearly identified cultural, provisioning, and support services, while regulating services were less recognized by visitors. The identification of BES may have been biased because direct-use provisioning services are crucial to both local economic and cultural elements, particularly tourism. Also, when asked about support services, they were not recognized as precursors of the other services. Consideration should be given to the most appropriate classification system for ecosystem services based on their fitness for purpose. Nevertheless, the research and questionnaire design may have contributed to the bias in the results presented here by approaching the classification of BES from research rather than a practical standpoint. In the present research, four categories were chosen. However, there are sometimes discrepancies in the identification of services, more so in the case of regulatory and support services, which causes confusion among visitors and requires a clear separation between them [2,14,40,60].

4.3. Willingness to Pay for Ecosystem Services of Beaches

Several studies of WTP for the preservation of the natural benefits of beaches have reported that visitors show a positive willingness to pay when the resources they could hypothetically contribute are used to preserve or improve the condition of beaches [1,2,14,18,52,60]. In particular, this study has found that a number of factors influence the presence of WTP (+) on both beaches, as determined by logistic regression analysis.

According to this study, the proposed WTP for the beach in Hawaii is USD 1.41/person/visit, while that of Bora Bora is USD 1.34/person/visit. The estimated willingness to pay for the ecosystem services of Hawaii and Bora Bora beaches guarantees their use and conservation, but there is a slight variation with respect to private beaches, which range from 1.58 USD to 2.63 USD, with the Botafogo, Miranda, and Taricaya beaches standing out.

Data from Hawaii and Bora Bora beaches showed that 58.2% and 59.5% of respondents, respectively, were willing to pay because, as in previous research, they believed the hypothetical situation would improve ecological services and benefit future generations [12,14,18,40,52], it was found that WTP (+) is not solely determined by income. Consequently, the logistic regression showed that the responses were influenced by the frequency of visits, interest in environmental issues, and time cost of access to the beach, all of which were mostly related to the secondary and higher education levels.

On the other hand, 41.8% of respondents who answered “no to payment” in Hawaii and 40.5% in Bora Bora are mostly at the same educational level. However, they are constrained by a moderate to low income. Moreover, 19.5% of respondents in Hawaii and 18.4% in Bora Bora said they could not afford it because they believe it is the government’s responsibility and because they do not trust the local government structures assigned to manage the funds, attributing this mistrust to high levels of corruption, a common problem in developing countries. On the other hand, 22% in Hawaii and 19.5% in Bora Bora did not do so because of their low income. The reality and analysis are similar to numerous studies conducted in inland water environments, such as lakes and rivers [12,15,18,24,57,61].

4.4. Limitations of the Study

It is important to remember that the contingent valuation approach used in the study could not have fully captured the more complex phases of the BES. This is because the method only allows for the detailed analysis of one scenario, rather than evaluating multiple potential scenarios in terms of environmental trade-offs and WTP. Therefore, it is suggested that a detailed analysis be carried out to address the various related aspects of how environmental change affects WTP, as well as social preferences in terms of the economic valuation of BES.

The quantification of the population of visitors to the beaches of Hawaii and Bora Bora was based on information provided by the locals, as there is currently no local, regional, or national institution that keeps records of visitors to the beaches. Based on this information, a sample was selected to analyze the WTP. On the other hand, many visitors were reluctant to be interviewed, so more time was needed for data collection.

5. Conclusions and Policy Implications

The beaches of Hawaii and Bora Bora, located near the city of Puerto Maldonado, are open to the public. Despite the lack of management by the competent authority, there is a high demand from bathers due to the favorable environmental conditions for recreational activities, despite the lack of infrastructure and basic services.

There was a higher representation of women among the total number of respondents. In the context of improving the quality of use and continuous maintenance of ecosystem services, the most influential socio-economic variables in WTP were identified as frequency of visits and interest in environmental issues in the case of Hawaii, and the cost of access time in the case of Bora Bora.

The average WTP per person per visit was USD 1.41 for Hawaii and USD 1.34 for Bora Bora. Visitor WTP results are lower than for private beaches, but consistent with the local socio-economic reality. However, it is important to analyze the data in monetary terms to ensure the continued provision and maintenance of ecological services.

The implementation of a strong environmental education policy is essential to increase the knowledge and commitment of visitors to river beaches. This education has a number of benefits, including the training of river beach managers, public access to relevant information on important river-related issues, direct community involvement in the management of river beach areas, and the promotion of environmentally sound practices to reduce negative impacts.

Consequently, since interest in environmental issues has emerged as a crucial factor in beaches, it is imperative to address environmental issues such as solid waste management and promote orderly visitation through education and awareness at various levels; initial, primary, secondary, and higher education, authorities, managers, visitors/bathers and tourism operators, in order to achieve greater awareness and ensure the sustainable use of river beaches.

Finally, it is necessary to implement a means of payment that gives confidence to the visitors, through funds managed by public-private institutions, where the value to be paid for the ecosystem service of the river beaches is intended for such purposes and not questioned for acts of corruption.