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:
ogical characteristics of
the crops and people’s production and business activities, largely dominated by light,
heat, water, gas and other climatic factors.
描述:
duction in the area is
restricted by disadvantageous natural resources and environmental conditions,
including low arable land area per capita, frequent drought events and a landscape
dominated by mountains. Forage crop rotation systems could improve soil fertility,
increase crop外eld and provide quality forage supplies for livestock production.
Additionally, their adoption is considered a suitable means to advance sustainable
agriculture development. In this study, the role and status of forage crop rotations in
Tianshui city were studied.
描述:
est region,
which c
ombined with the
water-saving, agricultural soil and water conservation techniques, and then taken "
drought
resistance, reduce erosion, increase efficiency" as a principle.
描述:
governors of HAN
Dynasty. The policy was carried out in most area of the west and the north. In
DONGHAN Dynasty, it also appeared in the inner area. The thesis is to tell opening
up wasteland and analyses the origin and features of opening up wasteland to get the
conclusion: Opening up wasteland in ancient times began in War times and was
developed fully in HAN Dynasty. Opening up wasteland in northwest area of HAN
Dynasty was only a comprehensive policy to defend the country, including the
content of politics
、
military and economy. It was t not for the people but for the
country. The policy was spread and lasted for a long time. In economy, it promoted
the development of agricultural economy in northwest area by bringing new tools and
ways of farming, which also joined the relationship between the central area and the
northwest. In politics, it laid a solid foundation for the unity of northwest area and the
victory against HUN. In culture, it advanced the communication and joint among
different races. Meanwhile, it was a base for opening up wasteland by troops and
common people in Cao Wei period.