描述:
ovement. Furthermore, analyses of
adverse effects on crop growth and development can probe into the crops’ adaptability to
adverse environments so as to optimize the breed selection and cultivation.
描述:
ncentrated v}}ith 85% of the
total dry lands. and it is important for the national economy and the countr<0's strategic
agricultural growth. Northwest arid areas basically depend on natural precipitation. water
shortage has seriously affected the farmers practices. The decision of farmers to plant dry
land is a two-stage decision-making behavior: They first have to decide whether to plant
dry land, and then decide what kind of crops planted in the dry lands. It is essential to find
effective ways to raise the enthusiasm of farmers planting and reasonable arrangements for
dry land crop structure. However. ver}} few people study dry land farming practice from the
perspective of water shortages.
描述:
f the earth's
surface.Therefore,it has great benefit for clarifying the mutual action between human
beings and land and their change principles in the historical period when the land use
and the land cover changes are chosen as the study perspective.
描述:
n the mountains. "Huaer" is such kind of song which is popular
in the areas of Gansu, Qinghai, Ningxia provinces. It is a cultural heritage
which has the most unique regional charm and features with rich contents
in northwestern region of China.
描述:
nd mingle, thus
breeding diversified and unique northwestern highland cultures, showing national
characteristics and original beauty, meanwhile forming a large number of tangible and
intangible cultural heritages.
描述:
basin in Gansu Province and Huangshui basin in Qinghai
Province. There have been found more than six hundreds tombs matching
this kind of culture in these years, however, the related or comprehensive
research are not many due to the limited sources. For this reason, I will
indicate its developed sequences and cultural characteristics } which are
based on materials from Xiaohandi tomb, Shanjiatou tomb as well as Lian
huatai tomb. Research methods include phased analysis of the帅ological
pottery and Comparative study on related tombs.