3.2.1. Evolution of Aggregation Degree of Sites

Through the Thiessen polygon division of the sites in the Xingyang–Guangwu trough area, the changes of the coefficient of variation (CV value) of polygons and the difference of the positive value of the domain area in each period were analyzed. These two values helped to study the evolution process of mutual distance and aggregation of sites in the area, and then to estimate the degree of resource and environmental impacts (Figure 5 and Table 1). difference of the positive value of the domain area in each period were analyzed. These two values helped to study the evolution process of mutual distance and aggregation of sites in the area, and then to estimate the degree of resource and environmental impacts (Figure 5 and Table 1).

*3.2. Spatial Aggregation Characteristics of the Xingyang–Guangwu Trough in the Typical* 

The study selected 128 settlements in different periods and different hierarchy structures in the Xingyang–Guangwu trough area to analyze the relationship between their

Through the Thiessen polygon division of the sites in the Xingyang–Guangwu trough area, the changes of the coefficient of variation (CV value) of polygons and the

*Water* **2022**, *14*, 2961 8 of 15

aggregation characteristics and the ancient lakes and swamps.

3.2.1. Evolution of Aggregation Degree of Sites

*Settlement Aggregation Area* 

**Figure 5.** Thiessen Polygonal Analysis map of Xingyang–Guangwu trough. (**a**) Yangshao period; (**b**) Longshan period; (**c**) Xia Dynasty; (**d**) Shang Dynasty. **Figure 5.** Thiessen Polygonal Analysis map of Xingyang–Guangwu trough. (**a**) Yangshao period; (**b**) Longshan period; (**c**) Xia Dynasty; (**d**) Shang Dynasty.

The sites were distributed in clusters and were greatly affected by environmental

cv area range cv area range cv area range cv area range


Xingyang–Guangwu trough 0.9 1.77–81.64 0.7 5.16–71.51 0.8 6.72–158.2 1.2 1.02–60.4

Xingyang–Guangwu trough 0.9 1.77–81.64 0.7 5.16–71.51 0.8 6.72–158.2 1.2 1.02–60.4

**Table 1.** Thiessen Polygon Analysis index table of Xingyang–Guangwu trough. **Table 1.** Thiessen Polygon Analysis index table of Xingyang–Guangwu trough.


3.2.2. Evolution of Lake and Swamp and Distribution Characteristics of Settlement Density in Different Periods 3.2.2. Evolution of Lake and Swamp and Distribution Characteristics of Settlement Density in Different Periods Further kernel density analysis was performed on the site data in different periods,

Xingyang–Guangwu trough area from the Yangshao period to the Xia–Shang Dynasties, the CV values of sites were all higher than 0.64, showing a significant clustering distribution pattern [32]. Among them, the distance between the sites of the Shang Dynasty was the closest, and the aggregation degree was the highest (Table 1)). In addition, the CV value and the positive difference of the domain area fluctuated in a wide range in each period, indicating that the number and distribution of the sites were greatly affected by

*Water* **2022**, *14*, 2961 9 of 15

Further kernel density analysis was performed on the site data in different periods, and visual processing was performed. According to relevant research and experimental analysis of the search radius and based on the overall scale of the Xingyang–Guangwu trough, 2 km was selected as the search radius of the kernel density analysis. At the same time, spatial overlay analysis was carried out on the ranges of the lakes and swamps and the kernel densities in different periods (Figure 6). and visual processing was performed. According to relevant research and experimental analysis of the search radius and based on the overall scale of the Xingyang–Guangwu trough, 2 km was selected as the search radius of the kernel density analysis. At the same time, spatial overlay analysis was carried out on the ranges of the lakes and swamps and the kernel densities in different periods (Figure 6).

(**a**) (**b**)

the environment.

(**c**) (**d**)

**Figure 6.** Kernel density analysis map of Xingyang–Guangwu trough. (**a**) Peiligang period; (**b**) Yangshao period; (**c**) Longshan period; (**d**) Xia and Shang Dynasty. **Figure 6.** Kernel density analysis map of Xingyang–Guangwu trough. (**a**) Peiligang period; (**b**) Yangshao period; (**c**) Longshan period; (**d**) Xia and Shang Dynasty.

The sites from the Peiligang period to the Xia–Shang Dynasties were mainly concentrated to the east of the Xingyang–Guangwu trough. With the changes of the lakes and swamps, the density distribution of sites in different periods had certain differences. Specifically: The sites from the Peiligang period to the Xia–Shang Dynasties were mainly concentrated to the east of the Xingyang–Guangwu trough. With the changes of the lakes and swamps, the density distribution of sites in different periods had certain differences. Specifically:


spread to the west of the lakes and swamps, forming two aggregation centers in the east and west. sites spread to the west of the lakes and swamps, forming two aggregation centers in the east and west. (4) During the Xia and Shang Dynasties, the lakes and swamps in the Xingyang–

(1) During the Peiligang period, the lakes and swamps were in the largest range and were widely distributed in this area. During this period, there were few sites around

(2) During the Yangshao period, the northern and western boundaries of the lakes and swamps did not change much, but the southern boundary receded to the north, and the eastern boundary receded to the west. With the recession of the eastern boundary of the lakes and swamps, the sites formed three aggregation centers in the east. (3) During the Longshan period, the western boundary of the lakes and swamps receded. The number of sites remained basically unchanged during this period, but the

the lakes and swamps, and no aggregation centers were formed.

*Water* **2022**, *14*, 2961 10 of 15

(4) During the Xia and Shang Dynasties, the lakes and swamps in the Xingyang–Guangwu trough disappeared, while the lakes and swamps in the east of the area with the Xingze lake as the center were in a stable period. During this period, the number of sites increased significantly, mainly located in the eastern part of the Xingyang– Guangwu trough and close to the Xingze lake and formed a gathering center, with Xiaoshuangqiao, Baizhai Mall, Daishigu, and other city sites as the core. Guangwu trough disappeared, while the lakes and swamps in the east of the area with the Xingze lake as the center were in a stable period. During this period, the number of sites increased significantly, mainly located in the eastern part of the Xingyang–Guangwu trough and close to the Xingze lake and formed a gathering center, with Xiaoshuangqiao, Baizhai Mall, Daishigu, and other city sites as the core.

3.2.3. Analysis of the Distance Relationship between Settlements of Different Levels and Adjacent Lake and Swamp 3.2.3. Analysis of the Distance Relationship between Settlements of Different Levels and Adjacent Lake and Swamp

The settlements of different scales and levels in the Xingyang–Guangwu trough area showed differences in distance from the surrounding lakes and swamps. Through the analysis of the relative distance between the two, the relationship between the spatial distribution characteristics of the settlement hierarchy and the lakes and swamps in different periods was explored. During the Yangshao and Longshan periods, Xingyang–Guangwu trough lakes and swamps still existed. Xizhang Village in the center of the lakes and swamps was selected as the center point, 5 km was the radius interval, and four buffer zones were divided; during the Xia and Shang Dynasties, the Xingyang–Guangwu trough lakes and swamps disappeared, but the Xingze lake on the east side of the trough still existed, which had an impact on the settlements in this area. However, the central location of the Xingze lake is still controversial. In this research, the western boundary of the Xingze lake, which is academically accepted, was selected as the reference point, and four buffer zones were divided with 5 km as the radius interval, counting and analyzing the number of settlements based on the hierarchy system in each buffer zone (Figure 7). The settlements of different scales and levels in the Xingyang–Guangwu trough area showed differences in distance from the surrounding lakes and swamps. Through the analysis of the relative distance between the two, the relationship between the spatial distribution characteristics of the settlement hierarchy and the lakes and swamps in different periods was explored. During the Yangshao and Longshan periods, Xingyang–Guangwu trough lakes and swamps still existed. Xizhang Village in the center of the lakes and swamps was selected as the center point, 5 km was the radius interval, and four buffer zones were divided; during the Xia and Shang Dynasties, the Xingyang–Guangwu trough lakes and swamps disappeared, but the Xingze lake on the east side of the trough still existed, which had an impact on the settlements in this area. However, the central location of the Xingze lake is still controversial. In this research, the western boundary of the Xingze lake, which is academically accepted, was selected as the reference point, and four buffer zones were divided with 5 km as the radius interval, counting and analyzing the number of settlements based on the hierarchy system in each buffer zone (Figure 7).

**Figure 7.** Buffer analysis map of Xingyang–Guangwu trough. (**a**) Yangshao period; (**b**) Longshan period; (**c**) Xia and Shang Dynasty. **Figure 7.** Buffer analysis map of Xingyang–Guangwu trough. (**a**) Yangshao period; (**b**) Longshan period; (**c**) Xia and Shang Dynasty.

in the 15 km buffer zone, and the number outside 15 km began to gradually decrease.

**Table 2.** A table of the distance between settlements and lakes and swamps in the Xingyang–

General settlement 1 10 14 13

General settlement 1 10 15 11

General settlement 9 20 15 8

*3.3. The Relationship between the Hierarchical Structure of Early Settlement Clusters and Lakes* 

Through the above analysis of the aggregation characteristics of the settlements in the Xingyang–Guangwu trough area, the following conclusions are offered: Due to the unique environment and geographical condition of the lakes and swamps, the hierarchical structure of early settlement communities clearly showed a concentric distribution around the lakes and swamps. This feature indicates that the early settlement clusters were closely related to the interactive development of the lakes and swamps. The specific pattern of

The results show that from the Yangshao period to the Xia–Shang Dynasties, the central settlements were generally located in the buffer zone of 5 km and 10 km close to the lakes and swamps, and the general settlements were mainly located in the middle and

The results in different periods are as follows: During the Yangshao period, the central settlements such as Qingtai and Wanggou settlements were concentrated in the 5 km and 10 km buffer zones in the eastern half of the lakes and swamps. The number of general settlements reached the maximum in the 15 km buffer zone and began to decrease in the 20 km buffer zone. In the Longshan period, there existed only the Chezhuang central settlement. Within the 10 km buffer zone in the center of the lakes and swamps, the number of general settlements reached the maximum within the 15 km buffer zone and began to decrease within the 20 km buffer zone. During the Xia–Shang Dynasties, the Xiaoshuangqiao settlement at its highest level concentrated in the buffer zone of 5 km. Central settlements such as the Dashigu settlement and Dongzhao settlement were located in the buffer zone of 10 km to 15 km. The number of general settlements reached the maximum in the buffer zone of 10 km and began to decrease in the buffer zone of 15 km

**Period Settlement Level 5 km 10 km 15 km 20 km** 

Yangshao period Central settlement 1 2 1 0

Longshan period Central settlement 0 1 0 1

Xia and Shang Dynasty Central settlement 4 2 4 0

this feature in different periods is as follows (Figure 8):

(Table 2).

*and Swamps* 

Guangwu trough area.

The results show that from the Yangshao period to the Xia–Shang Dynasties, the central settlements were generally located in the buffer zone of 5 km and 10 km close to the lakes and swamps, and the general settlements were mainly located in the middle and outer buffer zones of 15 km and 20 km. Furthermore, the number reached the maximum in the 15 km buffer zone, and the number outside 15 km began to gradually decrease.

The results in different periods are as follows: During the Yangshao period, the central settlements such as Qingtai and Wanggou settlements were concentrated in the 5 km and 10 km buffer zones in the eastern half of the lakes and swamps. The number of general settlements reached the maximum in the 15 km buffer zone and began to decrease in the 20 km buffer zone. In the Longshan period, there existed only the Chezhuang central settlement. Within the 10 km buffer zone in the center of the lakes and swamps, the number of general settlements reached the maximum within the 15 km buffer zone and began to decrease within the 20 km buffer zone. During the Xia–Shang Dynasties, the Xiaoshuangqiao settlement at its highest level concentrated in the buffer zone of 5 km. Central settlements such as the Dashigu settlement and Dongzhao settlement were located in the buffer zone of 10 km to 15 km. The number of general settlements reached the maximum in the buffer zone of 10 km and began to decrease in the buffer zone of 15 km (Table 2).

**Table 2.** A table of the distance between settlements and lakes and swamps in the Xingyang–Guangwu trough area.


*3.3. The Relationship between the Hierarchical Structure of Early Settlement Clusters and Lakes and Swamps*

Through the above analysis of the aggregation characteristics of the settlements in the Xingyang–Guangwu trough area, the following conclusions are offered: Due to the unique environment and geographical condition of the lakes and swamps, the hierarchical structure of early settlement communities clearly showed a concentric distribution around the lakes and swamps. This feature indicates that the early settlement clusters were closely related to the interactive development of the lakes and swamps. The specific pattern of this feature in different periods is as follows (Figure 8):


**Figure 8.** Concentric distribution map of early settlement circles. **Figure 8.** Concentric distribution map of early settlement circles.

#### **4. Discussion 4. Discussion**

inside to the outside.

central settlement.

The evolution of the ancient Yellow River distributary and its lakes and swamps had a significant impact on the early human living environment. Since the early Holocene, the west distributary of the ancient Yellow River disappeared, and the east ancient Yellow River distributary continued to flood, affecting the Xingyang–Guangwu trough area. The disappearance of the ancient Yellow River distributary provided the area with abundant natural resources. For example, flat, vast, and fertile land could be used for agricultural activities, and lake and swamp water resources could be used as fisheries. According to the research report of the animal bones collected in this area, the Chinese round snail and mussels accounted for 23% of the total [33]. A large number of freshwater wildlife found in this area could be closely related to the large area of shallow water lakes. Since the Shang Dynasty, the large-scale flat and fertile land after the disappearance of the western lakes and swamps provided a vast hinterland, and a complete and complex hierarchical settlement system was developed in this area. This spatial distribution characteristic fully demonstrates the harmonious relationship between humans and water under the influ-The evolution of the ancient Yellow River distributary and its lakes and swamps had a significant impact on the early human living environment. Since the early Holocene, the west distributary of the ancient Yellow River disappeared, and the east ancient Yellow River distributary continued to flood, affecting the Xingyang–Guangwu trough area. The disappearance of the ancient Yellow River distributary provided the area with abundant natural resources. For example, flat, vast, and fertile land could be used for agricultural activities, and lake and swamp water resources could be used as fisheries. According to the research report of the animal bones collected in this area, the Chinese round snail and mussels accounted for 23% of the total [33]. A large number of freshwater wildlife found in this area could be closely related to the large area of shallow water lakes. Since the Shang Dynasty, the large-scale flat and fertile land after the disappearance of the western lakes and swamps provided a vast hinterland, and a complete and complex hierarchical settlement system was developed in this area. This spatial distribution characteristic fully demonstrates the harmonious relationship between humans and water under the influence of the ancient Yellow River distributary.

(1) During the Yangshao period, central settlements were distributed in the nearest circle around the Xingyang–Guangwu trough lakes and swamps. The general settlements were mostly distributed in the outer circle. From the inner circle to the outer circle, the number of settlements first increased and then decreased, forming a concentric

(2) During the Longshan period, the settlements were distributed around the Xingyang– Guangwu trough lakes and swamps, and the number gradually decreased from the

(3) During the Xia and Shang dynasties, the Xingyang–Guangwu trough lakes and swamps disappeared, and the overall settlement structure reversed direction, forming a concentric distribution around the eastern Xingze lake. The highest-level settlement was distributed in the innermost circle, the secondary level settlement was located in the middle circle, and the general settlements were scattering around each

distribution feature surrounding lakes and swamps as a whole.

ence of the ancient Yellow River distributary. The data for this study were obtained from a multidisciplinary field. At present, the geographical environment, such as paleoclimate, paleogeology, and sedimentary experiments and determinations of rivers and lakes, are still in progress, and the archaeological investigation, exploration, and excavation of the sites in this area are still ongoing. This will provide more information and data for further in-depth analysis of this research and more precise lake and swamp boundaries and the resulting geographical units in each period will be clarified. It will contribute further to the study of the spatial connection between the sites. The data for this study were obtained from a multidisciplinary field. At present, the geographical environment, such as paleoclimate, paleogeology, and sedimentary experiments and determinations of rivers and lakes, are still in progress, and the archaeological investigation, exploration, and excavation of the sites in this area are still ongoing. This will provide more information and data for further in-depth analysis of this research and more precise lake and swamp boundaries and the resulting geographical units in each period will be clarified. It will contribute further to the study of the spatial connection between the sites.

#### **5. Conclusions**

Based on the geographical environment of the ancient Yellow River distributary and the vectorized data of early sites, this research uses the GIS spatial quantitative analysis method. From a multi-dimensional perspective, the typical settlement aggregation area (Xingyang–Guangwu trough area) of the ancient Yellow River distributary in Zhengzhou is identified. The study focuses on the area and conducts an overlay analysis of settlement in different periods, ancient lakes and swamps, topography, and other information. It shows the relationship between the changes of the ancient lakes and swamps and the aggregation degree, density distribution, and the evolution pattern of the settlement structure of the early sites. Research indicates:

(1) From the Peiligang period to the Xia and Shang dynasties, the early sites in the area where the ancient Yellow River distributary once flowed through show ribbon-like clustering features with multiple centers. The Xingyang–Guangwu trough area, which is a typical settlement area in the ancient Yellow River distributary area, is numerous and has a high degree of complexity of aggregations.


The early settlements showed aggregation characteristics under the influence of the ancient environments. This paper explores the mechanisms of settlement formation in such areas, and the research hopes to provide strong support for the systematic protection and overall display and utilization of cultural heritage-intensive areas.

**Author Contributions:** J.L., Y.S., W.Z. and J.Z. contributed equally to this research. Conceptualization, J.L. and Y.S.; writing—original draft, W.Z., J.L. and J.Z.; methodology, W.Z.; formal analysis, W.Z. and J.Z.; project administration, J.L.; writing—review and editing, J.Z. and Y.S.; funding acquisition, Y.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are available on request from all the authors.

**Acknowledgments:** All authors sincerely thank to Zhe Liu (School of architecture, Zhengzhou University) for his guidance on the language translation problem of the manuscript.

**Conflicts of Interest:** The authors declare no conflict of interest.

## **References**

