1. Profile along the Yellow River

(1) Element distribution characteristics of Juancheng (HA) profile

According to the spatial variation pattern of surface soil element content in the HA profile (Fig. 4-4a, b, c, d), the elements can be divided into 3 groups: The first group of elements: As, Cd, Co, Cr, Cu, F, Hg, Mg, Mo, Ni, Pb, V, Zn, Most elements such as Al, Fe, K, Ca, Mg; second group elements: P, Si, Na; third group elements: B, Se, N, S. The dotted line in the figure is the regional abnormal lower limit of each element, which is obtained from the statistics of surface soil element content values ??from the geochemical survey of more than 1:250,000 target areas in Shandong Province. The abnormal lower limit of each element is the average value + 2 times the deviation after excluding the abnormal values. Difference.

The content of the first group of elements at about 500 m from the beginning of the profile is low, while the content of the second group of elements except P is high. From the profile, it can be seen that this section is in the old Yellow River Before the dike.

From 500 m to 6 km, the content of the first group of elements is higher, and the content of most elements is higher than the lower limit of regional anomalies, but the anomaly contrast is not large; while the elements of the second group show negative anomalies or Low background.

The third group of elements has smaller changes in the HA profile, and the content is within the regional background range.

Figure 4-4a Element distribution map of Juancheng (HA) section along the Yellow River

Figure 4-4b Element distribution map of Juancheng (HA) section along the Yellow River

Figure 4-4c Element distribution map of Juancheng (HA) profile along the Yellow River

Figure 4-4d Element distribution map of Juancheng (HA) profile along the Yellow River

From soil vertical profile It can be seen that life elements and agricultural elements such as P and N show obvious surface enrichment in general. Elements such as Cd and Hg show obvious surface enrichment in individual vertical sections. The contents of other elements change irregularly with depth. sex. Overall, the vertical change patterns of the first group of elements are relatively consistent.

The changes in horizontal and vertical content of soil elements show that most trace elements (mainly the first group of elements) are controlled by the content of major elements, that is, together with the contents of Fe, Al, K, Ca, and Mg There is a positive waxing and waning relationship, but an inverse growth and decline relationship with Si and Na content.

(2) Element distribution characteristics of Pingyin (HB) profile

Similar to the HA profile, the elements in the HB profile can also be divided into 3 groups: the first group: As, Cd, Most elements such as Co, Cr, Cu, F, Hg, Mg, Mo, Ni, Pb, Se, V, Zn, Al, Fe, K, Ca, Mg; second group: P, Si, Na; third group Group: B, N, S. (Figure 4-5a, b, c, d)

At about 1 km away from the starting section of the profile, that is, within the Yellow River embankment, the content of the first group of elements is lower, while the content of the second group of elements is higher. High; from 1 to 6 km, the village density increases, the content of the first group of elements is higher, and most of them show abnormal facets, while the second group of elements have low background or negative anomalies; from 6 km to the end of the profile, the first group of elements The element content dropped to the background range, while the content of the second group of elements increased significantly, among which P showed an obvious abnormality. The third group of elements is similar to the HA profile, and its content changes irregularly. Among them, B and N have similar change characteristics to those of the first group of elements, but their content changes are smaller and have not reached abnormal content levels.

In the surface soil of the HB profile, trace elements such as As, Cr, and Mn have the most obvious anomalies, while other elements show weak anomalies. Vertical profiles of soil show that P, N, Se, S and other elements have strong surface enrichment characteristics, with P and N being the most enriched. Some vertical profiles are contaminated by Cd, Cu, Cr, Hg, Pb and other elements. The enrichment trend of elements in the surface layer is obvious. Similar to the HA profile, the vertical distribution characteristics of most elements are similar. It can also be seen from the spatial content change diagram of the surface soil and vertical soil in the HB profile that most trace elements (mainly the first group of elements) are controlled by major elements, and are expressed as Fe, Al, K, Ca, Mg The content waxes and wanes inversely with the Si and Na content, but this relationship is not as obvious as the HA profile.

(3) Element distribution characteristics of Lijin (HC) profile

Compared with HA and HB profiles, the contrast of trace element anomalies in HC profile is smaller, and the anomalies are mainly distributed in the front section of the profile. That is, within about 4.5 km before the Yellow River embankment and within 200 m from the beginning of the Yellow River profile, the contents of most trace elements are low. Abnormal elements mainly include: As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V, Zn, Se and other trace elements and Al, Fe, Ca, Mg and other major elements. Within this range, Si and Na are Negative anomaly distribution (Figure 4-6 a, b, c, d). Outside the Yellow River embankment 6 km away from the Yellow River, most trace and major elements show weak anomaly distribution, and the types of anomalous elements are the same as those in the first 4.5 km.

Different from the HA and HB profiles, the soil vertical profile reflects the As, Cd, Co, Cr, Cu, F, Hg, Mn, Mo, Ni, P, Pb, V, Zn, Se, Most elements such as N and S show varying degrees of surface enrichment, while major elements such as Al, Fe, K, Ca, and Mg also show obvious surface enrichment, while Si and Na show surface depletion. It is inferred that Surface enrichment of trace elements may be related to macroelements and their resulting soil physical and chemical properties.

2. Section along the Xiaoqing River

A large amount of industrial and urban domestic wastewater in Jinan City and along the Xiaoqing River is discharged into the Xiaoqing River. The ecological environment of the river has been seriously damaged, and the water in the Xiaoqing River has been severely damaged. , farmland in downstream areas is generally irrigated with river water, leading to pollution of farmland along the coast. Investigations show that various harmful elements are abnormally distributed in a large area along the Xiaoqing River and its tributaries. This study deployed two soil profiles perpendicular to the Xiaoqing River along the Xiaoqing River. One is located near Jinan City in the middle and upper reaches of the Xiaoqing River (XA profile), and the other is located near Dongying City in the lower reaches of the Xiaoqing River (XB profile).

Figure 4-5a Element distribution map of Pingyin (HB) profile along the Yellow River

Figure 4-5b Element distribution map of Pingyin (HB) profile along the Yellow River

Figure 4-5c Element distribution map of Pingyin (HB) profile along the Yellow River

Figure 4-5d Element distribution map of Pingyin (HB) profile along the Yellow River

Figure 4-6a Yellow River Element distribution map of Lijin (HC) profile along the Yellow River

Figure 4-6b Element distribution map of Lijin (HC) profile along the Yellow River

Figure 4-6c Element distribution in Lijin (HC) profile along the Yellow River Figure

Figure 4-6d Element distribution map of Lijin (HC) profile along the Yellow River

(1) Element distribution characteristics of Jinan (XA) profile

The XA profile is located Near Licheng, Jinan City. The section starts from the Yellow River, passes through Xiaoqing River and Jinan Iron and Steel Plant, and ends at the park southeast of Jinan Iron and Steel Plant. The section is in a densely populated area. The profile measurement uses farmland soil as the collection object. No samples were collected within about 2 km of the Jinan Iron and Steel Plant. Park soil was collected at the end point of the profile.

As can be seen from Figure 4-7a, b, c, d, there are occasional discontinuous As, Cd, Co, Cr, Cu, F within a range of about 3 km from the Yellow River to Xiaoqing River. , Mn, Mo, Ni, P, Pb, V, Zn, Se, N, S and other trace elements are abnormal. Compared with the profile distribution of major elements, it can be found that the spatial distribution characteristics of elements in this section are similar to those of the three Yellow River profiles, with smaller anomaly contrast and a mutually reinforcing relationship between trace elements and major elements.

Most trace elements in the adjacent Xiaoqing River show obvious abnormal distribution. At the same time, the macro elements also show obvious abnormalities. It is inferred that the trace element abnormalities here are due to the dual effects of Xiaoqing River pollution and soil texture. result.

In the section from Xiaoqinghe to Jinan Iron and Steel Plant, the contents of most elements fall within the background range, and the distribution of major elements is also very gentle. There are anomalies in elements such as Hg, Cd, Cr, Cu, Pb, and Se in this section, especially It is the Hg and Se abnormalities that are obvious.

Near the Jinan Iron and Steel Plant, Cu, Hg, P and other elements show a very obvious abnormal distribution, indicating the strong pollution impact of the Jinan Iron and Steel Plant on the nearby soil.

It can be seen from the element distribution characteristics in the vertical profile of the soil that Hg, Se, P, N, S and other elements show strong surface enrichment characteristics, especially Hg and Se elements from the Yellow River to adjacent Jinan Steel plant, the surface enrichment gradually increases, reflecting the increasing pollution levels of residents and Jinan Steel Plant.

(2) Element distribution characteristics of Dongying (XB) profile

This profile is located near Dongying City. It is a north-south profile that crosses the Xiaoqing River. The profile is 25 km long. The surface soil was collected at a point spacing of 500 m in each section, and the section at about 7 km in the Xiaoqing River crossed another river called the Branch River.

Multi-target regional geochemical surveys in the lower reaches of the Yellow River in Shandong Province show that there are large areas of trace element anomalies distributed in strips along the Xiaoqing River and branch rivers near Dongying. The anomalies trend parallel to the rivers and are distributed intermittently. .

As can be seen from Figure 4-8a, b, c, d, the entire profile has discontinuous distribution of various trace element anomalies from the starting end to about 20 km, and the anomalies of each element after 20 km Basically disappeared.

From the beginning of the profile to the branch river section, trace amounts of As, Cd, Co, Cr, Cu, Mo, Ni, F, Mn, Pb, V, Zn, Se, S, etc. are discontinuously distributed. The elements are abnormal, the abnormal contrast is small, and there is a certain wax and wane relationship with the spatial distribution of constant elements.

In the range from Branch River to Xiaoqing River, the abnormal contrast of trace elements such as As, B, Cd, Co, Cr, Cu, Pb, V, Zn, Mo, Ni, F, and Mn is relatively large. Correspondingly, there is also an obvious abnormal distribution of major elements in this range, which is characterized by low Si and Na and high Al, Fe, K, Ca, and Mg. It is similar to the three profiles along the Yellow River. It is inferred that this range Internal trace element anomalies are mainly caused by soil macrocomponents (texture).

The element contents of the 6 vertical soil profiles collected along the profile vary greatly, but the regularity is poor. Only elements such as N and Hg, Se and P on some vertical profiles show obvious surface enrichments. set, but careful observation shows that the vertical distribution characteristics of each trace element seem to be related to the vertical changes of the major elements.

Figure 4-7a Element distribution map of Jinan (XA) section along the Xiaoqing River

Figure 4-7b Element distribution map of Jinan (XA) section along the Xiaoqing River

Figure 4-7c Element distribution map of Jinan (XA) section along the Xiaoqing River

Figure 4-7d Element distribution map of Jinan (XA) section along the Xiaoqing River

Figure 4-8a Small Element distribution map of Dongying (XB) section along the Qinghe River

Figure 4-8b Element distribution map of Dongying (XB) section along the Xiaoqing River

Figure 4-8c Dongying (XB) section along the Xiaoqing River Profile element distribution map

Figure 4-8d Dongying (XB) profile element distribution map along the Xiaoqing River

3. Profile along the Tuhai River

Multiple target areas Geochemical surveys found that trace amounts of heavy metals occasionally appeared abnormally along the Tuhai River. In this survey, a profile (TA profile) was set up to conduct research on anomalies near Yucheng.

As can be seen from Figure 4-9a, b, c, d, elements such as As, Cd, Co, Cr, Cu, F, Mn, Mo, Ni, Pb, V, Zn, and Se on this section The anomalies are mainly concentrated in the range of 2.5 km to 10.5 km of the profile, and the anomaly contrast is small. Only elements such as Cd, Hg, and P develop strong single-point anomalies. The abnormal distribution of most trace elements in this profile is similar to several profiles along the Yellow River and the Xiaoqing River XB profile. It shows that the abnormal spatial distribution of major elements is coupled with the anomalies of most trace elements, mostly concentrated in the 2.5-10.5 km profile range. , among which SiO2 and Na2 O show negative anomalies, while Al2 O3, Fe2 O3, MgO, CaO and K2 O show positive anomalies, reflecting that the distribution of trace elements is restricted by major elements (soil texture); B, Hg, P, Elements such as N and S are similar to the aforementioned profiles, with no obvious regularity and no large-scale abnormalities except for a few points.

In the vertical direction of the soil, elements such as P, Se, and N show obvious surface enrichment, while the hierarchical enrichment of other elements is not obvious. The vertical changes in trace element content also show characteristics related to the macroelement content.