描述:
t important methods
commonly used in the prehistoric culture exhibiton. Scene reappearance is not simply
an artistic creation, but a serious scientific work. Which archaeological information
描述:
th, the demand of water resource is
continuously increasing. That is to say water shortage has become a global problem. Water
resources carrying capacity is the basis and prerequisite of regional socio-economic development,
which is significant to realize the coordinated development of regional "water resources-
ecological environment-socio-economy" composite system. So it has become the focus and hot
topic in water science field nowdays.
描述:
th, the demand of water resource is
continuously increasing. That is to say water shortage has become a global problem. Water
resources carrying capacity is the basis and prerequisite of regional socio-economic development,
which is significant to realize the coordinated development of regional "water resources-
ecological environment-socio-economy" composite system. So it has become the focus and hot
topic in water science field nowdays.
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:
large-scale farming tool that can
water
continuously from the ground-surface water in the rivers, lakes, or pools, and is mainly applied to lifting
water to the high ground or drain water in the low-lying farmland. Due to the reason that the traditional
描述:
be given when fully and rational use of local
climatic resources such as solar radiation, heat and water, while other conditions (such as soil
fertility, carbon dioxide concentration, cultivation level etc.)
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:
ttention, but
also agriculture and eco-environmental sustainable development important
problems. Farming-pastoral Transitional zone in north China, as our county
returning farmland to forest and returning cropping land to grassland are the
focus areas, natural environment and socio-economic conditions shown a
clear transition characterized by the transition zone of the interpenetration and
staggered distribution of agriculture and animal husbandry, which is curbing
desertification important ecological barrier, but also ecologically fragile belts.