Sustainable Development and Soils in the Portuguese Education System: Open Problems and Further Challenges

Abstract

The curricular documents for Basic Education Sciences in Portuguese schools (ages 6 to 15) that currently affect teachers and students across the world integrate Sustainable Development concerns regarding soils. A sharp gap emerges between the official documents and the teachers’ perceptions of how to approach such issues. Urgent measures are required to bridge both worlds: reformulations of the official documents that guide teachers’ practices and educational resources focused on soils from a Sustainable Development perspective. A new organization of the curricular documents for this theme that aims to promote quality education among Portuguese Basic Education schools worldwide is proposed.

1. Introduction

In 2015, the United Nations [1] established the Sustainable Development Goals (SDGs) with the purpose of creating achievable goals by 2030, aiming to improve quality of life and safeguard the planet. This vision of the future reflects concerns about the various challenges that societies face, which result from a growing imbalance between what citizens need and the resources available on Earth. As so, radical changes in citizens’ unsustainable consumption rates are required to mitigate current problems affecting society, namely those emerging from the fragility of the physical environment [2]. To this end, it is essential to promote an education that encourages the integration of all knowledge in inter- and transdisciplinary approaches, which demands overcoming the traditionally established gap between the natural and the human and social sciences and integrating natural and social and humanistic scientific knowledge with non-scientific and non-Western forms of knowledge [3].

The conservation of Earth’s resources for future generations is everyone’s responsibility and imposes new challenges for all sectors of society (politicians, businessmen, educators, media), including the geoscientists, as their activity is focused on the production and use of geoscience knowledge [2,4].

The role of geosciences in achieving SDGs is widely recognized, namely in areas such as agrogeology (where SDGs 1, 2, 3 and 15 can be enhanced), climate change (that meets SDGs 1, 2, 11, 13 and 14), geological hazards (that promotes SDGs 1, 2, 11 and 13), or hydrogeology (that relates to SDGs 1, 2, 3, 6, 11, 12, 13, 14 and 15) [5]. To this end, the development of specific skills in geosciences education is particularly important, such as practical work, whether in the laboratory or in the field. However, the role of geosciences can be extended to other less obvious domains that are the target of the 2030 Agenda, such as achieving gender equality and empowering all women and girls at all levels of decision making, which is the aim of the 5th goal of the 2030 Agenda [6], or to provide teaching resources regarding fieldwork activities [7] in geoconservation studies to assist geoeducation practices (e.g., [8,9]), therefore meeting the 8th, 11th and 12th goals of the 2030 Agenda [5].

However, there is a lack of recognition of the role of geosciences in achieving these and other SDGs, one of the explanations being that, in most countries, there is no commitment to this area of knowledge in school curricula [10]. Another recognized justification is the worrying underrepresentation of geologists in scientific publications on sustainability [11]. As a way of overcoming these constraints, Stewart and Gill [12] suggest, “Firstly, our geoscience community needs to substantially broaden its experience. And secondly, we need to explicitly integrate “sustainability” into geoscience education, training and continued professional development” (p. 167).

The current organization of the Portuguese education system covers pre-school education and 12 years of schooling. It includes 9 years corresponding to three cycles of Basic Education (the 1st cycle is 4 years, i.e., ages 6 to 10; the 2nd cycle is 2 years, i.e., ages 10 to 12; and the 3rd cycle is 3 years, i.e., ages 12 to 15) and three years of Secondary Education (ages 15 to 18). In the 1st cycle, the teaching of geology is dispersed in other areas of knowledge (i.e., biology, physics, history) in the subject of Environmental Studies. In the 2nd and 3rd cycles of General Basic Education, geology is included within the discipline of Natural Sciences with Biology themes. In secondary education in the Scientific Area, in the first two years, the subject is called Biology and Geology, with an equitable division of topics in the two areas per academic year. In the third year of secondary education, Geology is an independent discipline, but it is optional [8].

The organization of the Portuguese education system decisively influences not only school communities in Portugal but also those that are guided by the same curriculum in Portuguese-speaking countries spread across Africa, Asia and Oceania [13,14,15,16]. The Network of Portuguese School in Portugal during the academic year 2020/2021 involved a total of 147,041 teachers and 1,595,312 students, and the Network of Portuguese Schools Abroad involved a total of 925 teachers and 10,525 students (Figure 1).

The United Nations General Assembly voted unanimously to approve 2008 as the International Year of Planet Earth (IYPE) framed within the United Nations Decade for Education for Sustainable Development (2005–2014). The IYPE aimed to build on the existing knowledge of some half a million Earth scientists all over the world and make it more available for the improvement of everyday life, as expressed in the Year’s subtitle: Earth Sciences for Society. “Soil: Earth’s living skin” was among the scientific themes selected for the IYPE, and promoting sustainable extraction of Earth’s resources was among the range of the initiative’s objectives [17,18]. In fact, the thematic “soil” is one of the geosciences issues that provide close relationships with the 2030 Agenda and, according to Lal et al. [19], its sustainable use is critical to meet several SDGs.

Table 1. Examples that express how learning about soils can contribute to achieving different SDGs (adapted from [19]).

SDGs	Goal	How Developing the Theme “Soils” Can Promote the Achievement of SDGs
1	No poverty	Depending on the characteristics of each region, sustainable soil management and improved agricultural exploitation can be key factors in eliminating poverty.
2	Zero hunger	Sustainable soil management is fundamental to achieve SDG2, thus mitigating one of humanity’s greatest enemies (hunger), currently exacerbated by the COVID-19 pandemic.
3	Good health and well-being	Healthy soils generate healthy crops which, in turn, nourish the animals, enabling their health and productivity. Soils can also indirectly contribute to well-being and health, as they are important in creating medicines, filtering water, providing shelter, creating clothes, forming fuel...
4	Quality education	Soil education can contribute considerably to improve the quality of education due to its holistic and interdisciplinary character. Curriculum changes should incorporate dimensions that aim to increase awareness about soils, i.e., to educate and communicate about soils to promote quality education, in an integrated approach to face environmental problems. The relationship between soil and its role in food security, women’s empowerment and environmental sustainability (SDGs 2, 5 and 15) are important themes for students to explore in a school context, thus promoting work capacity, leadership, collaboration and inclusiveness.
5	Gender equality	Equal opportunities are sought for women in soil sciences, which continue to be few in this area (and others), namely in the composition of editorial boards of journals and funding panels, in the leadership of conferences, …
6	Clean water and sanitation	Soils play an important role in the circulation, storage and transformation of water and influence the quality and availability of water supply. For example, unsustainable agricultural practices imply less soil organic matter, facilitating the transfer of pollutants to groundwater and causing problems in water quality.
9	Industry, Innovation and Infrastructure	Promote local soil-based food production and appropriate and sustainable strategies, thus reducing, for example, dependence on food imports. A stable soil with a high infiltration capacity can decrease the rate of surface runoff and keep soil particles together, reducing sediment loads in the runoff, which can help, for example, in reducing the accumulation of sediments in channels and dams. It is important to know how soils are handled, stored and reused in construction projects, always encouraging best practices promotion.
11	Sustainable cities and communities	Urban development affects local soils in terms of sealing, densification, excavation and pollution. The original soils are highly impacted and are partially eliminated or mixed. Possible solutions include urban gardening or vertical gardening. Lately, with the COVID-19 pandemic, awareness of the positive effects of gardening and agriculture in urban contexts has increased considerably. Additionally, the production, management and potential recycling of urban waste are important issues for the sustainability of cities, as the organic fraction of urban waste could (and should) be conveniently treated and recycled through composting, to later be used in agricultural soils.
12	Responsible consumption and production	Learning from small-scale farming methods, enhancing the sustainable use of soils and scientific knowledge of sustainable food systems. Food production in local food chains fosters a local circular economy and reduces the associated pollution. The need to produce animal products (meat, dairy products) compared to plant production requires changes in the human diet, namely more plant-based consumption.
13	Climate action	Climate change has a major impact on soils and vice versa. Therefore, sustainable land management is essential so that we can face a climate crisis and produce enough food while adapting to a changing climate.
15	Life on land	It is intended to promote the sustainable use of terrestrial ecosystems, reverse soil degradation affected by desertification, drought and floods, and mitigate the loss of biodiversity, thus achieving neutrality of soil degradation and benefiting our own survival.
16	Peace, justice and strong institutions	Fertile and productive soil plays an important role in establishing food security. A safe and healthy agricultural sector plays a vital role in preventing conflicts and migration and, ultimately, building peace and stability. Soil science also assists in the characterization of illegal environmental deposits with toxic residues and environmental contaminants. Deep cooperation in criminal justice can reduce corruption and bribery, associated, for example, with illegal trade in geological resources.

suggests several examples that show how learning about soils can contribute to achieving different SDGs.

All these examples of articulations between the theme “soils” and the SDGs imply the need for collaboration between professionals from various sectors, namely, politicians, engineers, researchers, technicians, and other professionals in areas related to soil (directly or indirectly), in addition to teachers.

The present study aims to characterize the approach to the theme “soils” in Portuguese schools, considering the SDGs of the 2030 Agenda. To this end, the framework of the curricular documents of the Sciences of Basic Education was analyzed, as well as the perceptions of a group of science teachers of Basic Education (from 6 to 15 years old) about these curricular documents and about their educational practices. Suggestions are also presented that aim at a better adaptation of the contents and the organization of the Essential Learning documents for Basic Education in the approach of the theme “soils” in a Sustainable Development (SD) perspective.

2. Methodology

The accomplishment of the present investigation was based on two methodologies aimed at: (1) verifying whether the curricular documents of Sciences for Basic Education in Portuguese schools (ages 6 to 15) present guidelines to develop themes related to soils that promote SDGs; (2) analyzing science teachers’ perceptions about their practices and the approach to the theme “soils” from an SD perspective.

2.1. Methodology for the Analysis of Curriculum Documents

This investigation fits into the interpretive paradigm with a qualitative approach to the study subject [20,21]. It followed a descriptive-interpretative strategy of an exploratory nature [20], privileging the content analysis [22] of the documents that constituted the corpus of analysis.

In this research, a content analysis was carried out on the curriculum documents of Sciences for Basic Education in Portuguese schools. The pre-defined categories, understood as rubrics with specific meanings according to which the corpus was classified by the researchers [23], allowed us to situate the apprehension of the object of analysis and make it relevant in relation to its objectives [20]. These categories resulted from a theoretical framework based on the proposal by Lal et al. [19], which is presented in Table 1.

Table 2. Definition of the categories of the analysis instrument used in the present study. The relationship between soils and SDGs was established according to Lal et al. [19].

SDG’s	Category	Codification
1	No poverty	C1
2	Zero hunger	C2
3	Good health and well-being	C3
4	Quality education	C4
5	Gender equality	C5
6	Clean water and sanitation	C6
9	Industry, Innovation and Infrastructure	C7
11	Sustainable cities and communities	C8
12	Responsible consumption and production	C9
13	Climate action	C10
15	Life on land	C11
16	Peace, justice and strong institutions	C12

shows the relationship between the SDGs and the category that will be considered for this analysis and the respective coding.

The analysis instrument used was designed and adapted for documents with specific characteristics (curricular and transversal). Thus, the proposed analysis/categorization reflects the researcher’s experience as a teacher, namely in the correlations she establishes when interpreting these documents, which may be questionable for other researchers.

The collected corpus consists of official curricular documents for science subjects in Basic Education, as well as two documents considered transversal to different subjects, but which are deemed crucial to understand the DS concept (

Table 3. List of eleven documents of the corpus by cycles of Basic Education, subjects, grade and respective bibliographic references.

Documents	Cycle	Science Subjects	Schooling Grade
Essential Learning	1st (ages 6 to 10)	Environmental Studies	First [24]
			Second [25]
			Third [26]
			Fourth [27]
	2nd (ages 11 to 12)	Natural Sciences	Fifth [28]
			Sixth [29]
	3rd (ages 13 to 15)	Natural Sciences	Seventh [30]
			Eighth [31]
			Ninth [32]
Student’s Profile by the End of Compulsory Schooling	1st, 2nd and 3rd (ages 6 to 15)	Transversal	First to ninth [33]
Referential Environmental Education for Sustainability	1st, 2nd and 3rd (ages 6 to 15)	Transversal	First to ninth [34]

).

After all the categorization of these documents, the analysis was validated by three specialists in different but converging areas (Science Education, Geology and SD), because “with the help of experts, the researcher confronts whether his categories of analysis may represent (or not) aspects of a theory or topic he intends to investigate” [21] (p. 222). This validation resulted in minor adjustments to the categorization already included in the results presented in Section 3.1.

In the following subsections, the analysis methodology adopted will be described per document.

2.1.1. Essential Learning

The Essential Learning documents are organized by subjects and schooling grades (Table 3). Taking into account the twelve categories of the analysis instrument (Table 2) used to categorize the corpus, the evidence related to soils in the Geosciences Topics of these documents was grouped. Section 3.1.1 presents the results of this analysis, as well as its discussion, also considering the SDGs to which they are related.

2.1.2. Student’s Profile by the End of Compulsory Schooling

This document is described “as a reference document for the organization of the entire education system, contributing to the convergence and articulation of decisions inherent to the various dimensions of curriculum development” [33] (p. 8). It defines Principles, Vision, Values and Areas of Competence that are intended to be developed throughout the 12 years of compulsory education.

“Sustainability” is defined as one of the eight guiding principles, and “one of the greatest existential challenges of the contemporary world, which consists of establishing, through political, ethical and scientific innovation, lasting and safe synergy and symbiosis relationships between social, economic and technological systems and the Earth System, on whose fragile and complex balance the historical continuity of human civilization depends” [33] (p. 14). The results of this analysis are presented in Section 3.1.2.

2.1.3. Referential Environmental Education for Sustainability

This document is part of the set of references prepared by the General Directorate of Education in the context of Education for Citizenship, aiming to guide the implementation of sustainability within the curriculum in the different teaching cycles. Thus, this categorization was made by the teaching cycle.

The document is organized by themes, sub-themes and objectives. In this work, what was categorized was Table III of this document [34] (pp. 16–19), where the themes, sub-themes and objectives by teaching cycle appear; the themes related to “soils” were identified in the geoscience topics. Only the organizing table of the topics covered in this document was analyzed, highlighting the references that can be included in the categories of analysis that were established in

Table 4. Number of references by category of the Essential Learning documents.

Categories	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10	C11	C12	TOTAL
Number of references	2	2	11	37	0	9	12	11	9	4	28	3	128

. Section 3.1.3 presents the results of this analysis, as well as its discussion, also considering the SDGs with which they can be related.

2.2. Methodology for Analysis of the Perceptions of Teachers on Teaching Practices

This investigation used a quantitative approach, with statistical analyses being carried out on the collected data. A search was made using a questionnaire that was applied to 14 teachers from a group of schools in central Portugal, who were selected because they were interested in attending an in-service teacher education on Geoscience Didactics. The design and validation of this questionnaire were included in João et al. [35]. This questionnaire consists of two parts: one regarding the teachers’ characterization and another that assesses the teachers’ perceptions about their educational practices in the development of geology themes, namely from an SD perspective. The group of teachers answered the questionnaire before starting an in-service teacher education program on Geoscience Didactics designed to overcome teachers’ needs as a result of the research outputs presented in the following section.

3. Results

This section reports the results of the Analysis of Curriculum Documents (Section 3.1) and the Analysis of perceptions of teachers on teaching practices (Section 3.2) regarding the approach to the theme “soils” in the Portuguese education system, taking the SDGs of the 2030 Agenda into account.

3.1. Analysis of Curriculum Documents

In the following subsections, the results of the analysis are presented for each type of curriculum document.

3.1.1. Essential Learning

The Essential Learning documents were analyzed by school grade, identifying the references related to each of the defined categories. Table 4 shows the number of references identified by category, and the graph in Figure 2 represents the number of references by category and by school grade.

Category C4 “Quality education” stands out with 37 references, as it was considered that all references identified relating the soil to the SDG’s contribute to the promotion of quality education. Regarding all these references, which are important topics for students to explore in a school context, they show that: or they are presented with a holistic and interdisciplinary character; and/or they promote soil awareness, as well as soil education and communication, in an integrated approach to environmental problems; and/or they emphasize the relationship between soil and its role in food security.

The second category with the highest number of references (28) is C11, “Life on land,” as the theme “soils” often arises from the need to reverse its degradation, minimize desertification and face drought, and from the implications that those phenomena have on ecosystems balance and biodiversity conservation. For example, the Essential Learning document for the 8th grade refers “Critically analyze the role of rocks and soil in the existence of life in the terrestrial environment and of the subsystems in the maintenance of life” [31] (p. 8). Category C5 “Gender equality” is the only category among these documents that does not have any reference associated with the theme “soils”.

Of the 128 categorized references, most are concentrated in the 8th grade, and this fact may be associated with the themes of this school grade, in which the promotion of sustainability on Earth planet is clearly highlighted. It should be noted that category C4 “Quality education” is the one that has references in all analyzed school years. Categories C3 “Good health and well-being” and C11 “Life on land” have references in eight of the nine schooling grades under study. The 9th grade displays the lowest number of references, only three. Most schooling grades have references in different categories of analysis, which shows how easily the theme “soils” from a DS perspective can be approached in different ways by relating it to different areas, namely agriculture, health, infrastructure, water, biodiversity and justice.

3.1.2. Student’s Profile by the End of Compulsory Schooling

The Student’s Profile by the End of Compulsory Schooling document, which supports all curriculum documents, is organized into eight guiding principles, one of which is sustainability. Thus, as this document is articulated with the Essential Learning document, sustainability is considered a principle that cuts across all themes.

3.1.3. Referential Environmental Education for Sustainability

Figure 3 represents the number of references per analysis category in each cycle of Basic Education recognized from the analysis of the Referential Environmental Education for Sustainability document. In a total of 245 references, all categories have references in this document, but the highest number of references (83) is in the 3rd Cycle of Basic Education.

The category that displays the highest number of references throughout Basic Education is C4 “Quality Education,” as once again it was considered that all references promote this SDG.

3.2. Analysis of Perceptions of Teachers on Teaching Practices

The 14 teachers involved in this analysis have a permanent contract with the same school cluster and have more than 25 years of practice (6 between 25 and 29 years, 4 from 30 to 34 years, and 4 from 35 to 40 years). With regard to their academic profile,

Table 5. Academic profile of the teachers participating in the study by teaching cycle of Basic Education.

1st Cycle			2nd Cycle	3rd Cycle
Primary Teaching Course	Complementary Training	Master Degree	Graduation Degree	Graduation Degree	Master Degree
6	5	1	5	3	1

shows the number of teachers by teaching cycle with a Primary Teaching Course + Complementary Training, Graduation and Master degrees.

The preservice teacher education of the 1st Cycle of Basic Education is generalist, including several subjects that cover different knowledge areas. Regarding the 8 teachers of the 2nd and 3rd Cycles, who teach Biology and Geology contents, 4 have preservice teacher education only in Biology, 3 only in Geology and 1 in Natural Sciences (Biology and Geology).

The results related to teachers’ perceptions of their educational practices are described in the following subsections. They are presented in accordance with three different dimensions: “Actions/valences that they consider as facilitators for science education” (3.2.1); “Strategies/activities they adopt to teach geoscience topics” (3.2.2); and “Constraints they identify to teach geoscience topics” (3.2.3).

3.2.1. Actions/Valences Considered as Facilitators for Science Education

The teachers considered almost all actions/valences presented as important or very important in promoting science education (Figure 4). The actions/valences to be implemented/to have in science classes that all teachers considered “Very important” for the training of young citizens are: (i) “Include practical science activities in all teaching cycles”; (ii) “Explore the importance of scientific literacy in everyday life”; (iii) “Teaching science using active teaching and learning strategies (teaching by research, by projects...)”; (iv) Address science topics provided in the curricular guidelines from a perspective of promoting sustainable development”.

Thirteen of the fourteen also consider as “Very important”: (i) “Having science resources and equipment in schools (lab material, teaching kits...),” (ii) “Having a science laboratory at school since the 1st Cycle of Basic Education,” (iii) “Show the useful/practical nature of science contents,” and (iv) “Identify and explore the presence of S&T in the different dimensions of students’ daily lives, namely at home (e.g., reading labels), in health (e.g., more effective drugs), in the media (e.g., computer; mobile phone)”.

On the contrary, the action that is classified by more teachers (two) as “Nothing/Little important” was “Stimulating meetings between researchers and the educational community.” Moreover, the action “Start science education from the earliest years” was classified as “Not at all/Little important” by one of the teachers.

It is also worth noting the actions considered “Moderately Important” by more teachers (five): (i) “Conduct a sequential teaching of the same topics throughout the teaching cycles” and (ii) “Promote meetings between researchers and the educational community.” The issue regarding the relevance of promoting the sequential teaching of the same themes throughout the different teaching years/cycles is highlighted because, although all teachers consider it as “moderately important” (five) or “very important” (nine), in another questionnaire, three teachers admitted that they do not consider this concern (Figure 5).

Eleven teachers mentioned that when planning their classes, they consider whether students have already addressed the same topics in previous years and if/how they will address them in later years. Of these eleven, the majority (seven) claim that they seek to analyze “(…) the official documents of the other schooling grades of the same education cycle.” In relation to the other grades of other teaching cycles, fewer teachers referred to this analysis, only three. Some even mentioned that they met with colleagues from the same cycle who teach different grades (four) and only two with colleagues from other cycles.

It should also be noted that all the teachers considered “Very important” “To approach science topics provided in the curricular guidelines in a perspective of promoting sustainable development.” Given the importance, it was deemed necessary to deepen the understanding that teachers have about the SD dimensions through the type of relationships that they establish between the environmental, economic and social dimensions of SD and the theme “soils” (Figure 6).

All teachers related the theme “soils” to the environmental dimension of SD (14 to “Natural resources—exploitation and consumption”; 13 to “Risks and consequences of the use of natural resources”). Still in the environmental dimension, the category “Social and ethical issues in STSE” was mentioned by only one teacher, while the category “World human population” was mentioned by only two teachers. The four categories that no teacher related to the theme “soils” are all included in the social dimension. Moreover, the remaining categories of this dimension have little expressiveness. The economic dimension of the “soils” theme is recognized by some teachers but less frequently than the environmental one.

3.2.2. Adopted Strategies/Activities to Teach Geoscience Topics

Figure 7 shows the implementation frequency of strategies/activities to teach geoscience topics in teachers’ practices. All teachers reported that they frequently adopted two of the strategies/activities presented: the “Exploration of the themes relating them to the daily lives of the students” and the “Resolution of exercises from the manuals by the students, which are later revised in the class group.” Also, all teachers say that they often or sometimes adopt the “Elaboration of concept maps with students,” the “Exploration of PowerPoint^® presentations,” the “Exploration of the textbook (e.g., reading aloud, underlining parts of the textbook...),” the “Survey of the students’ previous ideas about the curricular themes before starting their exploration,” and the “Conducting of practical experimental activities by the teacher for the students to see”.

On the other hand, the strategies/activities that most teachers admit they do not adopt (not once) are “Exploration of digital resources (e.g., sensors, mobile applications—APP...),” “Organization of visits by researchers/specialists for dialogue and/or development of some activity,” and “Participation with students in contests and/or meetings and/or science seminars.” Also noteworthy is the strategy/activity “Exploration of themes from a sustainable development perspective,” which twelve teachers admit to frequently use, one a few times and another says never to do so.

It should be added that three teachers mentioned that they adopted other strategies/activities not referred to in the presented list of statements. Two did not specify which ones, and one added that he sometimes guides research work about a certain theme with a subsequent presentation of the results by the students to the class.

3.2.3. Identified Constraints in Teaching Geoscience Topics

Figure 8 shows the opinion of teachers in relation to a list of statements (adapted from [37]), which are presented as possible constraints for the teaching of geoscience topics (rocks, minerals, soils, earthquakes, volcanoes, fossils...).

All the statements/constraints presented were recognized by some teachers. Eleven of the fourteen teachers surveyed agreed that “The number of students per class sometimes makes it difficult to carry out practical activities,” and ten teachers agreed that “The lack of laboratory technicians greatly limits the performance of practical activities, namely geosciences,” “The carrying out of fieldtrips has logistical and financial constraints,” and “Laboratories do not have adequate resources to carry out practical geoscience activities.” Half of the teachers (seven) agreed that “The lack of supporting documents/guides/guidelines for the teacher makes it difficult to carry out practical activities on geoscience topics.” In the context of this work, it is also worth noting that five teachers agreed that “The exploration of geoscience themes in the context of Sustainable Development implies more work for the teacher, in the planning and definition of teaching resources to be used” and three understood that “The preparation of geosciences themes from a perspective of Education for Sustainable Development is not part of the program/curriculum guidelines/goals/essential learning.” In addition to the constraints presented, more related to teaching practices, teachers were also asked for their opinions on their own training, initial and continuous, to understand whether this issue would also be a possible constraint for teaching geoscience topics (Figure 9).

Although the majority stated that they had specific training in geoscience didactics, half of the teachers said that they had not developed plans and didactic resources to explore geoscience topics, the majority admitting that today they recognize that the initial training they had was not enough to feel prepared to teach geoscience topics in Basic Education.

Teachers’ opinions on the need for continuing education to teach geoscience topics are represented in Figure 10. Most of the surveyed teachers felt the need to undergo continuous training, both in didactics and geoscience topics. However, only a minority had attended these programs or others specifically in SD. The justification that most teachers gave for this low attendance was “because I never found training on this topic here in the area that I could attend”.

4. Discussion

The theme “soils” is represented in all analyzed documents of Essential Learning (from the 1st to the 9th grades of Basic Education). However, it appears that these references are mostly aimed at exploring the properties and characteristics of soils, while orientations to explore other articulations, namely with food and water resources, are less frequent. However, such articulations are indispensable in view of the need to reduce the levels of hunger in the world and of poverty in general (SDG 2 and SDG1, respectively). According to [19], it is necessary to review school curricula periodically, and the theme “soils” must be present at all levels of education, properly articulated with the problems that emerge from its unsustainable use, from the perspective of promoting environmental, social and economic sustainability. Among these documents (Essential Learning of Environmental Studies and of Natural Sciences), the environmental dimension is overestimated [38], leading teachers to strongly link the term sustainability to environmental aspects and rarely to economic and social aspects [39,40]. However, sustainable solutions require global thinking and local actions, fostered by true transdisciplinary education, at all levels, that overcome the established division between the natural and the human and social sciences that guides current education visions [3].

In the Student’s Profile by the End of Compulsory Schooling document, there is an explicit reference to the concept of sustainability, defined as one of the eight guiding principles across all years and themes. This document is articulated with the Essential Learning documents; therefore, it assumes, although not explicitly, the relevance of promoting sustainability. One of the Competency Areas defined (“Well-being, health and environment”) specifically aims to foster education for SD.

The Referential Environmental Education for Sustainability document, in its entirety, aims to promote education for sustainability. It is organized by teaching cycles, and although it defines “Themes,” “Sub-themes,” “Objectives” and “Performance Descriptors,” it does not present a clear orientation of how to relate them with the themes of the Essential Learning documents. Thus, it is necessary to establish a clear articulation between these two documents, that is, to point out references from the Referential Environmental Education for Sustainability document in the Essential Learning documents, thereby contributing to assisting teachers’ practices in sustainability issues.

The themes included in the Essential Learning documents are organized from a spiral perspective; that is, the themes reappear throughout basic schooling, aiming at a successively more in-depth approach. However, according to [41], this perspective can compromise students’ learning due to gaps and/or repetitions in the exploration of these themes throughout their schooling. Those gaps and/or repetitions can essentially emerge from the fact that most teachers do not know the curricular documents assigned to other schooling grades and/or cycles, which can normally result in a repetition (and not a more in-depth approach to the themes) noticed by the students [42]. In addition, the results obtained from the answers to the questionnaire applied in this work show that not all teachers are concerned about knowing if their students have already worked on the themes they will teach to avoid these repetitions and/or gaps. Some mentioned that they analyzed the official documents of the schooling grades of the same education cycle, but few considered documents related to other cycles. This question is included in the Essential Learning Implementation Assessment Report [43], in which the issue of vertical and horizontal articulations is one of the greatest difficulties recognized by the surveyed teachers. Other international studies corroborate these difficulties [44,45,46] and add, as possible justifications, the lack of didactic resources and the inadequate training of teachers. Orale and Uy [44] identified another problem in this spiral organization, calling it “When the spiral is broken”, which refers to students’ difficulties when they were not able to master the previous themes and then are subject to them, but approached in a more complex way.

As for the most frequently used strategies/activities, we highlight the exploration of the themes relating them to the students’ daily lives, the resolution of exercises in the school textbook, and subsequent revision in the classroom. According to a recent study developed by the Observatory of Educational Resources, more than 92% of teachers (out of the 4590 teachers from 1st to 12th grades who participated in that study) systematically resort to textbooks to prepare their plans [47]. The over-use of school textbooks in guiding pedagogical practices, therefore replacing official curriculum documents when teachers plan their classes, is very worrying since there is practically no articulation between the Essential Learning documents and the textbooks [43]. This situation was also emphasized in other studies [48,49] that recognized the occurrence of some mismatch between school textbooks and current curricular documents, which makes the school textbook an unsuitable working tool in the teaching and learning process.

Another highlight derives from the fact that all the teachers involved in the present investigation assume that they carry out (sometimes or frequently) experimental practical activities for the students to see; that is, the students do not carry them out, being limited to observing them. This situation, in the approach to geoscience themes, is justified by the teachers participating in this investigation: (i) by the high number of students per class, (ii) by the lack of conditions in the laboratories, (iii) by the lack of guides to support the teacher, and even (iv) by the deficient initial training they had and the reduced offer of continuous training in the experimental teaching of geosciences. These arguments were also recognized in other similar studies, namely by Andrade & Massabni [50] and by Souza et al. [51].

Regarding infrastructures, whose inadequacy the teachers considered to limit the performance of practical work in geosciences, Rodrigues et al. [52] found this difficulty in implementing experimental activities in the 1st Cycle of Basic Education, and in the 2nd and 3rd Cycles of Basic Education in 152 schools in central Portugal: only 24% of those have properly equipped science laboratories, in 8% of the schools the science rooms are spaces that have the same furniture as any other classroom intended for the teaching of another subject, and in 68% of the schools the spaces fall within the typology called “pseudo-laboratories” (i.e., they correspond to rooms intended for science teaching, but without the appropriate characteristics to promote practical activities, having only, for example, side benches or water points, therefore corresponding to normal classrooms).

Some of the results from this investigation open the door for further exploration of this issue in other studies, which may incorporate data gathered using other instruments to enable triangulation of findings and enhancement of the conclusions that are given here.

5. Towards a New Approach to “Soils” in Portuguese Curricular Documents

To promote quality education regarding the role of soils in achieving the 2030 Agenda goals Basic Education teachers at Portuguese schools need adequate teaching resources and education focused on soils from an SD perspective. However, above that, the official documents that guide their practices require some improvements to make them clearer, better organized, and more efficient, namely by promoting the sequential implementation of the soil theme, encouraging students to carry out practical work, and suggesting new assessment strategies.

Appendix A includes a new proposal for the implementation of the theme “soils” in the Essential Learning documents of Basic Education in Portuguese schools. To support this proposal, curricular documents in Earth Sciences from other countries were analyzed (Singapore, Canada, United States of America, England and Australia). The selection criteria for these countries were: (i) having obtained good results in the TIMSS 2019 in Earth Sciences, (ii) covering different continents (different cultures), (iii) having the curriculum documents available for consultation, (iv) having a more complete structure than the current Portuguese Essential Learning documents, namely presenting possible articulations of the theme with other schooling grades (thus promoting its sequential implementation), and displaying proposals for evaluation strategies.

6. Conclusions

The importance of studying soils to achieve DSGs is unavoidable, and the school’s role in this purpose is widely recognized. The present work reports research aimed at characterizing the approach to the theme “soils” in Portugal and in Portuguese schools across the world (around 148,000 teachers and more than 1.5 million students during the 2021/2022 school year), considering the SDGs of the 2030 Agenda.

This research reveals that the curricular documents of the Sciences of Basic Education that guide geoscientific education integrate SD concerns regarding soils as an important natural resource to achieve SDGs. They include nine documents of Essential Learning, i.e., one per schooling grade, and two transversal reference documents (i.e., Student’s Profile by the End of Compulsory Schooling and Referential Environmental Education for Sustainability). However, the content analyses of these documents show that they lack articulation between them, therefore being of limited use to the teachers for whom they are intended. In fact, although all teachers relate the theme “soils” to the environmental dimension of SD, their perceptions about how to approach such issues during their practices show a great discrepancy in relation to the official documents’ aims and scope. Reasons include the replacement of curricular documents by textbooks in their practices despite their recognized inadequacy to meet the official documents rationale, the logistics constraints in the teaching of geoscience topics and their need to undergo continuous training, both in didactics and on geoscience topics.

Policy makers in charge of conceiving curricular norms and conditions for their implementation on the ground and education actors seem to inhabit worlds apart, making it difficult to educate students to face current problems resulting from the unsustainable use of soils. Urgent measures are required to bridge both worlds and provide effective quality education.

On the one hand, official documents need to be clearer, more coherent and designed to be understood and used by the educational actors in real scenarios. However, any reformulation of curriculum documents presupposes the previous discussion and validation by in-service teachers, and it cannot be exclusively determined by policy makers. To overcome the current gap that separates the world of curriculum documents from the world of educational practices, teachers should be consulted, as they are particularly aware of the day-to-day constraints that they face to equip their pupils with adequate skills to mitigate current problems affecting society and that jeopardize their future.

This work proposes reorganization for the implementation of the theme “soils” in the Essential Learning of Basic Education documents in Portuguese schools that emerged from the results obtained throughout this research. However, for the proposed suggestions to have an impact on teachers’ practices, it is essential to provide them with didactic resources aligned with SD concerns regarding soils, as well as to conceive and develop education programs designed to assist the teachers in the development of their work with the respective students. These programs will have to correspond to the needs and expectations of teachers and must be in line with the SDGs, thus contributing to improving their self-confidence in implementing innovative approaches in their practices and promoting quality education.