[Research progress on carbon sink function of agroforestry system under climate change].

As a land comprehensive utilization system, agroforestry system can absorb and fix CO2 effectively to increase carbon storage, and also reduces greenhouse effect convincingly while reaching the aim of harvest. The regulatory role in CO2 makes humans realize that agroforestry systems have significant superiority compared with single cropping systems, therefore, understanding the carbon sinks of different components in an agroforestry system and its influencing factors play an important role in studying global carbon cycle and accurate evaluation of carbon budget. This paper reviewed the concept and classification of agroforestry system, and then the carbon sequestration potentials of different components in agroforestry systems and influencing factors.

[Photosynthetic rate, transpiration rate, and water use efficiency of cotton canopy in oasis edge of Linze].

The measurement system of Li-8100 carbon flux and the modified assimilation chamber were used to study the photosynthetic characteristics of cotton (Gossypium hirsutum L.) canopy in the oasis edge region in middle reach of Heihe River Basin, mid Hexi Corridor of Gansu. At the experimental site, soil respiration and evaporation rates were significantly higher in late June than in early August, and the diurnal variation of canopy photosynthetic rate showed single-peak type.

Canopy and leaf gas exchange of Haloxylon ammodendron under different soil moisture regimes.

In order to reveal the drought resistance and adaptation of the C(4) desert plant Haloxylon ammodendron under artificially controlled soil moisture regimes, representative plants were selected to measure canopy photosynthesis using canopy photosynthetic measurement system. The results showed that appropriate soil moisture significantly enhances the canopy and leaf photosynthetic capacity, and extremely high soil moisture is not conducive to the photosynthesis of H. ammodendron.

[Effects of farmland shelterbelt on photosynthetic characteristics and grain yield of maize in Hexi corridor oasis].

Farmland shelterbelt is a main component of oasis agro-ecosystem in the Hexi corridor of Gansu Province, which plays an important role in maintaining local agricultural production and ecological balance. This paper studied the photosynthetic characteristics of maize at its grain-filling stage and the grain yield of maize under the protection of the shelterbelt. The results showed that at the same distances east and west of the shelterbelt, maize plants at the east side always intercepted more photosynthetic active radiation (PAR) than those at the west side.