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:
ch as the important town
of the Silk Road, multi-ethnic coexistence and the border district administrative center.
In order to ensure normal exchange between the East and the West, frequent contact
among ethnicities, and effective administration in He-xi area, it was extremely
essential to establish city defense. Therefore, the Tang government built the city
defense system that was mainly military defense and based on social balance. Mainly
included the screen protective system of Army, Shouzhuo, City, Town, Shu, etc.,
which had some focal point and very wide and located out of the cities; Three layers
external protective system that was composed of a deep ditch to round every city,
sheep and horses cities, city wall; Multiple structure system such Luo city(outer city),
Zi city(inner city), fang(residential area), Shi(markets), and so on; Garrison inside
cities and out of locality system; Feng, Yi and other information systems; General's
office person of ability system; Warehouse reserve and social balance system.
Because of the important geographical position strategic and the special social
security problem, the He-xi Prefecture and county city defense had formed Trinity
characteristic with the national defense and the security defense. The city defense
soldiers had a hand in Tuntian to bring about He-xi area’s agricultural advance; A
large number of people of city defense formed the consumer market, had promoted
the prosperity of the commerce; The city defense ensured traffic and military
assistance, made He-xi Prefecture and county cities become the rear base to
administer Central Asia. However, the city defense had its limitation, such as
impotent military might at times (it offered an opportunity of Tibetan expanded in
north-west area), because of the condition between the country and the locality. It, to
a certain extent, had influenced on the valid function of city defense.
描述:
isasters in China,
the earthquake caused the largest number of deaths accounted for 54% of the total
number, and 80-90% of China's earthquake occurred in rural areas.
描述:
stics of the basic
conditions for the development of agricultural industry in Jiuquan City and, the
situation of and constraints in the development of featured agricultural industry,
aiming at seeking an approach to futher develop the featured agricultural industry in
the city of Jiuquan.
描述:
siea. Low temperature is the key factor that limits
the growth, colour and appreciatability in winter in the northern of China. Introducing foreign gene
into kale through genetic engineering may create novel variety with cold tolerance. In this study,
BADH(encoding betaine aldehyde dehydrogenase) and TCH(encoding transcription regulation
factors) were used to be transformed into kale with Agrobacterium-mediated transformation.
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.