1. Introduction
Shandong peninsula is located in North China and surrounded by Bohai Sea and Yellow Sea with the coastline more than 3000 km. There are two types of coast-plain coast and harbor bay coast. During the past decades the coastal erosion along Shandong Peninsula was obviously aggravated by the interaction of human activities and coastal dynamic forces. Modern coastal erosion has severe effects on the development of marine economy, coastal environment and coastal landforms.

2. Modern coastal erosion and its results

2.1 Modern coastal erosion
Based on the field investigation and collected related data, modern coastal erosion along Shandong Peninsula have three features as follows:
(1) Widespreading coastal erosion and high erosion rate
Along the coast of Yellow River Delta, the coastal erosion near to the abandoned river mouth is obvious in spite of the sedimentation and regression at the present river mouth. From 1855AD, the "new land " was formed at a average rate of 23.5 km²/a because of the sedimentation in front of the Yellow River mouth, and at the same time the erosion took place along the coast near to the abandoned river mouth. For example, about 330 km² land was lost during 1949-1976 and along Shenxiangou river mouth there was 2.8 km transgression in the period of 1961-1964 at the average erosion rate of 930 m/a.

From Zimai River mouth to Bailang River mouth along Laizhou Bay, the coastline was erode with 200-300 m transgression at a average rate 6-10 m/a during the past 30 years. From Jiaolai River mouth to Hutouya, the average erosion rate was 68-100 m/a with the 1.5-2.0 km transgression during the period of 1954-1976.

The harbor bay coast along Shandong Peninsula is the main type of coast. The sandy beaches have undergone severe erosion in the past 30 years with the average rate of 2 m/a.

(2) Obviously seasonal changes of coastal erosion
The most severe coastal erosion along Shandong Peninsula is directly affected by wind surges and typhoon surges. So the changes of coastal erosion have obvious seasonal characteristics. During the summer season the typhoon surges can cause great damage for the coastal area and rapid coastal erosion. For example, the coastal erosion along Shandong Peninsula during No9216 typhoon in 1992 is shown in Tab.1

Tab.1 Coastal erosion along Shandong Peninsula during No.9216 typhoon*

Whole coast area Longkou&Penlai Rizhao Haiyang&Rushan Qingdao

Coastal erosion widespread& 2-10 m 4-6 m 8-10 m 20-40 m & transgression 145.3ha land losed Economic lose 43.5×108yuan Dead person 76

* Coastal erosion & transgression refer to the sandy beaches

(3) ntensifying coastal erosion caused by human activities
During the past decades, many dams intercepted the sand to the sea and the runoff mostly used for industry and agriculture as well as the exploitation on sandy beaches along Shandong Peninsula increased rapidly. All above caused a total sand loss at 2×107 t/a, which intensified the coastal erosion during the condition of wind surges and typhoon surges.

2.2 Results of coastal erosion
The results of coastal erosion in Shandong Peninsula include:

1. the loss of land resources;
2. the damage of coastal forest;
3. the destroy of coastal building and sea walls;
4. the ground water pollution because of the intruding sea water;
5. the loss of potential tourist resources;
6. the damage of coastal sea-farming;
7. the loss of some coastal environment benefiting for the marine creatures.

3 Conversation coastal landforms

Various coastal landforms provide important natural environment for coastal bio-diversity, and usually coastal landforms such as the sand beaches and pebble beaches have the function for coastal tourism. The coastal erosion will destroy the coastal environment and beaches. In Shandong Peninsula the coastal tourism is flourishing and is one of the key aspects for economic development in 21th century. There are many cases of coastal erosion which are harm to the coastal tourism. So the conversation of coastal landforms is urgent for the government and the public in the coastal area along Shandong Peninsula. The countermeasures for protecting coastal landforms are shown as follows:

3.1 Based on scientific investigations, To determine the coastal areas which is most urgent to protection.

3.2 To adopt a series measures to control the coastal erosion along Shandong Peninsula. mplementing beach nourishment and engineering renovation suitable to local coastal conditions.

3.3 For the purpose of avoiding irrational exploitation of coastal resources, to educate the public especially the local government officials with perfect knowledge of marine engineering and coastal landforms.