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Construction of Ecosystem Model of English Writing for Minority College Students

Based on the Ecological Systems Theory, this paper constructs an ecosystem model of English writing for minority college students. The ecosystem includes Microsystem, Mesosystem, Exosystem, Macrosystem and Chronosystem. Based on this model, this paper analyzes the main tasks of language policy makers and foreign language teachers and the new challenges faced by minority students in English learning. Keywords—English writing; minority college students, Ecological Systems

INTRODUCTION Construction of the ecological civilization is a long-term plan that will affect the well-being of the people and the future of the nation. In the face of the severe situation of tighter resource constraints, serious environmental pollution and degradation of ecosystems, it is necessary to establish the concept of ecological civilization that respects, adapts to and protects nature, and give priority to the construction of ecological civilization. The construction of ecological civilization should be integrated into all aspects and the whole process of economic, political, cultural and social development. Chinese people are responsible for building a beautiful China so as to achieve the lasting development of the Chinese nation.
The construction of ecological civilization this paper is talking about can be understood as the impact of ecological environment on our lives from a macro perspective. Then, from the microscopic point of view, the ecological environment that affects the learning of English by minority college students has its own unique performance. English writing ability is a concentrated expression of students' English comprehensive ability. Therefore, it has practical significance to explore the ecosystem structure that affects the English writing of minority college students. Ethnic minority college students are an indispensable force for building a beautiful China and realizing the lasting development of the Chinese nation. Under the background of globalization, the English writing ability of ethnic minority college students affects their contribution to the national economic, political, cultural and social constructions. Then, through the reverse thinking, we can say that the current national economy, politics, culture, and society are part of the ecosystem of English writing that constitutes ethnic minority college students.
Based on the Ecological Systems Theory, this paper attempts to construct an ecosystem model of English writing for minority college students. Based on this model, what are the main tasks of language policy makers and foreign language teachers in order to improve the English writing ability of minority college students? What are the new challenges for minority college students in learning English?
II. ECOLOGICAL SYSTEMS THEORY The Ecological Systems Theory is also called the Development in Context or the Human Ecology Theory. The Ecological Systems Theory was proposed and perfected by Urie Bronfenbrenner [1]. The theory holds that a person will be developed under the influence of several environmental systems and is generally accepted as a leadership theory in the field of development psychology. The Ecological Systems Theory has five interconnected environmental systems: Ⓐ Microsystem, which is the direct environment inclusive of the family, the school, and the peer group. Ⓑ Mesosystem, which consists of direct environmental connections, such as, the impact of home and school on children. Ⓒ Exosystem, which refers to the indirectly external environmental conditions, such as, the impact of the parent's workplace on the child. Ⓓ Macrosystem, which refers to larger cultural background, such as, western culture, national economy, politics, culture, etc. Ⓔ Chronosystem, which refers to the changes in the living environment and lifestyle.
In the Ecological Systems Theory, the four systems of Microsystem, Mesosystem, Exosystem and Macrosystem are nested, and the fifth Chronosystem runs through the first four systems. The five systems interact with each other.

MINORITY COLLEGE STUDENTS
The English writing of minority college students is one of their social activities, so it is necessary to study the English writing of minority college students from the standpoint of humanism. Writing can express students' thoughts and feelings and reflect the complex relationships between minority college students and their families, teachers, classmates, and their life circle. We should study the psychological and cognitive processes of minority college students in English writing. It is even more important for us to study how minority college students use a foreign language (for most minority college students, it is a third language) to write in a certain social, economic, political, and cultural environment and under certain material conditions.

A. Microsystem
In the Ecological Systems Theory, Microsystem is the direct environment, which refers to the direct impact of families, schools, and peer groups on individual development. As far as the development of students' English writing ability is concerned, the direct influencing factors include English writing rhetoric theory, English writing theory, English writing teaching theory, English writing teaching activities, students' English writing activities and so on.
The rhetorical theory of English writing discussed in this paper is not a rhetorical device such as metaphor, personification, or rhetorical question. The so-called rhetoric is the intention of conveying meaning, including the subject of writing, the purpose of writing, the object of writing, and the individual's writing motivation [2]. For minority college students, the rhetoric environment of English writing is more complex, involving the constraints and influence of crossethnic, cross-cultural, and cross-social factors. In English writing, the author should pay attention to whom the article is written for, and must use the correct language, appropriate language, and clear meaning [3]. In addition to diaries, most of the purpose of writing is to communicate with others, even if the composition of the exam is the same. The better communication effect the composition has, the higher score the teacher will give. If writing is only for one's own purpose, write as one wants, but in a society where people interact, English writing is also a tool for communication, and proper use of English rhetoric will add a lot to the effectiveness of communication. Then the learner's writing is both educational and entertaining. In English writing, the theoretical knowledge of English writing is an indispensable tool for learners to improve the quality of English writing [4]. Learners can master basic writing skills such as lexical, syntactic, grammatical, textual structure, and basic expressions such as description, description, explanation, and discussion. At the same time, they can properly apply the rhetoric theory of English writing. In this way, students have laid a solid foundation for improving their English writing ability.
Each country has formed its own schools and methods based on the research and practice of teaching English writing according to its own social conditions, economic development, cultural status, and education. In China, the method of English writing for minority college students is still in the process of exploration and has not yet reached a conclusion. For example, the teaching theories of English writing include the resultsoriented teaching method, the process-oriented teaching method, the teaching method of only paying attention to the language forms of students' writing, the teaching method of only paying attention to the contents of students' writing, and the teaching method of genre.
The classroom teaching environment of English writing also has a direct influence on students' writing. There are various forms of English writing teaching for minority college students. For example, the forms can be lecture-style teaching activities, conversational teaching activities, seminar teaching activities, practical activity teaching activities, competitive teaching activities, and free learning-style teaching activities. The English level of minority college students is generally relatively low, so the students' English writing activities mainly include English basic sentence writing exercises, writing a diary, translation exercises for English writing, peer revision, regular English writing exercises, and so on.

B. Mesosystem
Mesosystem consists of direct environmental connections, namely, the impact of home and school on children. For the development of students' English writing ability, the Mesosystem is, in the direct environment, the influence of English writing rhetoric theory, English writing theory, English writing teaching theory, English writing teaching activities, and students' English writing activities together on students' English writing ability.
The influence of various factors on students' English writing ability in the Microsystem will have an interactive effect. English writing rhetoric theory and English writing theory will influence the formation of English writing teaching schools. English writing teaching schools will guide English writing teaching activities and students' English writing activities. For minority college students, the English writing teaching activities will determine the students' English writing activities, and the feedback from the students' English writing activities will cause the English writing teaching activities. According to the special performance of minority college students, the teaching schools of English writing with minority characteristics will be formed. Therefore, the rhetoric theory of English writing and the theory of English writing will be continuously improved. It can be seen that the four factors in the Mesosystem affect the performance of minority college students' English writing at the same time.

C. Exosystem
Exosystem refers to the indirectly external environmental conditions. For the development of English writing ability of minority college students, the external environment conditions that indirectly affect them are also the conditions that affect the four factors of Microsystem. That is, the external environmental conditions will affect the English writing rhetoric theory, English writing theory, English writing teaching theory, English writing teaching activities, and students' English writing activities.
The language courses offered for minority college students from elementary school to middle school include both the native language and the mandarin. Their English writing behavior will inevitably have the influence of both the mother tongue and the mandarin. Therefore, the rhetoric theory of native language writing and native language writing theory, together with Chinese writing rhetoric theory and Chinese writing theory, will affect the rhetoric theory and English writing theory of minority college students. The teaching theory of native language writing and the teaching theory of Chinese writing will affect the teaching theory of English writing for minority college students. Chinese writing teaching Advances in Social Science, Education and Humanities Research, volume 322 activities and Chinese writing teaching activities will affect the English writing teaching activities for minority college students. Students' native language writing activities and Chinese writing activities will affect the English writing activities of minority college students.

D. Macrosystem
Macrosystem refers to larger cultural background. For college students, the expression of views, values, and philosophy of life in their English writing cannot be separated from the cultural environment they live in, the surrounding cultural environment, the cultural environment they learn through books, and so on.
Minority college students have lived in their own cultural atmosphere since they were young. Therefore, they have formed a sense of love for their own culture since they were young, and they have been influenced by their own excellent traditional culture since they were young. From the perspective of cultural communication, they have borne the burden of inheriting and promoting the outstanding national culture. China is a multi-ethnic country. The cultures of various ethnic groups will influence and infiltrate each other, and constantly absorb the parts of other ethnic cultures that they need. In particular, ethnic minorities continue to absorb the outstanding elements of Han culture. While Chinese minority college students are learning English, they are naturally exposed to Western culture. They have the opportunity to learn from the world's outstanding cultural achievements, but at the same time they also face the severe challenges of Western cultural products and values. Therefore, minority college students should be allowed to selectively accept Western culture.
The formulation and implementation of the national language education policy must safeguard and realize the cultural interests of the country [5]. That is to say, the English writing of minority college students should promote the dissemination of ethnic languages and cultures in China, and on the other hand, promote the national language and cultural identity and national cohesion. The development of the national economy will determine the demand for language. In the context of deepening reform, the English language skills mastered by minority college students will play a positive role in the development of ethnic areas. Contemporary minority college students must have a high degree of political literacy and ability to judge what are right and what are wrong. Therefore, when they express their opinions in English writing, they must not have political prejudice or prejudice against the motherland.

E. Chronosystem
Chronosystem refers to the changes in the living environment and lifestyle. For minority college students, Chronosystem refers to a change of lifestyle and learning environment.
The development of the English writing ability of minority college students changes with time. Time and environment are combined to explore the dynamic process of this development. The way of life of minority college students includes their material life, values, moral values, aesthetic values and other spiritual life, such as clothing, food, housing, traveling, labor and study, rest and entertainment, social exchanges, and dealing with other people. The way of their lives reflects the period when they grew up and the social conditions under which various minorities lived. Their English writing ability develops with the development of their life style. Their learning environment includes school learning environment, family learning environment and social learning environment. The school learning environment refers to the school building, teachers, teaching conditions, teaching means, school atmosphere, and style of study. The family learning environment refers to the material conditions that the family provides for students to study, such as comfortable rooms, harmonious family relations, and family members who can help students learn. The social learning environment refers to the social atmosphere that influences students to establish a correct outlook on life, a world view, and a learning purpose [6]. The change of learning environment has often become a driving force for the development of English writing ability of minority college students.

A. The main tasks of language policy makers and foreign language teachers
Based on this model, in the process of improving the English writing ability of minority college students, the role played by policy makers is mainly reflected in the Macrosystem and some of Exosystem, that is, policy makers should create an ecological environment that is conducive to the physical and mental health of minority college students from a macro perspective. The minority college students can have a positive attitude in English writing, produce outstanding minority talents, and play an active role in promoting the process of building a moderately prosperous society. The role played by foreign language teachers is mainly reflected in Microsystems, Mesosystem, and Exosystem. Foreign language teachers must study and discuss the Chinese, English and native writing rhetoric theory, writing theory and writing teaching theory suitable for minority college students. Under the guidance of these kinds of theories, writing teaching activities are effectively implemented. Students are scientifically and rationally organized to do some writing. Efforts are made to create a micro-ecological environment suitable for the development of English writing ability of minority college students. Specifically, teachers should choose or compile English writing materials suitable for minority college students [7]. In the classroom, students should be centered in English writing activities.

B. The new challenges faced by minority students in English learning
Minority college students are the hope for the development of minority regions. English learning plays a very important role in improving the comprehensive quality of minority college students. In addition to the influence of native language and Chinese language, the influence of other ecological factors cannot be ignored. Therefore, the minority university students must understand the country's political system, national economic development, the country's language education policy. On the basis of the promotion of the national culture, the minority university students should understand the culture of other ethnic groups in the country. For western culture, the minority university students should take its essence and get rid of its dross. In short, to meet the needs of the new situation, the minority university students should actively meet the challenges from all aspects.
V. CONCLUSION According to the discussion above, the ecological system of English writing for minority college students is shown in Fig. 1.
In this system, the four systems of Microsystem, Mesosystem, Exosystem and Macrosystem are nested, and the fifth Chronosystem runs through the first four systems. Each of the four factors in the Microsystem will affect the English writing performance of minority college students, while the Mesosystem will show that each of the four factors will affect the English writing performance of minority college students at the same time. The Exosystem affects Microsystem and Mesosystem, and therefore also affects the performance of minority college students in English writing. The influence of Macrosystem is reflected by national politics, national economy, national language education policy, national culture, other national cultures, and Western culture. The influence of Microsystem, Mesosystem, Exosystem and Macrosystem on the English writing performance of minority college students will change with time. These five systems thus constitute a whole system--the English writing ecosystem of minority college students.
ACKNOWLEDGMENT I would like to give my sincere gratitude to Prof. Yang Liqun, my colleague who, with extraordinary patience and consistent encouragement, gave me great help by providing me with necessary materials, advice of great value and inspiration of new ideas.