Takyric solonetz is spread mainly in arid area，Northwest China． Its poor soil structure and
extremely low hydraulic conductivities ( Ks ＜ 0. 1 mm/d) are the key factors restricting its amelioration．
The ECe
( electrical conductivity of saturated paste extract) ，SAＲe
( sodium adsorption ratio of saturated
paste extract) ，and pHs
( pH of saturated paste) of the native soil studied at depth of 0 ～ 30 cm were
12. 30 dS /m，44. 12 ( mmol /L) 0. 5 and 9. 33，respectively． After deep tillage，beds ( 1. 0 m width，0. 5 m
height) were formed． The drip lines were placed on beds covered with plastic． Lycium barbarum L．
seedlings were then planted． A three-year field experiment was conducted to determine if reclamation
could be achieved while cropping Lycium barbarum L． by using drip irrigation where soil beneath the dripemitters near the plants was replaced with sand in niches that were 0. 2 m ground diameter and 0. 2 m
depth． The purpose of sand-filled niche was to increase the area over which infiltration of water occured
thereby reducing the application rates to values that more closely matched the saturated hydraulic
conductivity of the native soil，provide a reservoir for holding the applied water before it infiltrated and
avoid the adversely mechanical impact and the stirring action of applied water on soil surface． Five
treatments based on soil matric potential ( SMP) thresholds used to trigger drip irrigation were designed to
find the optimal drip irrigation schedule，i． e． ， － 5 kPa ( S1) ， － 10 kPa ( S2) ， － 15 kPa ( S3) ，
－ 20 kPa ( S4) and － 25 kPa ( S5) ． The results showed that significant improvement was achieved in
soil infiltration capability，which was demonstrated by the increasingly enlarged wetted area beneath the
drip emitter． Consequently，a desalt region ( ECe ＜ 4 dS /m) was formed，and high SMP level was
favorable for the salt-leaching in soil． The ratio of ECe /SAＲe was increased significantly after planting，
which indicated the changes of soil salt composition characteristics and the amelioration of soil physical
properties． After planting with drip irrigation，the contents of soil available nutrients were increased
sharply． Nitrate nitrogen showed a high migration with water movement，and had potential to be lost by
leaching，so nitrogen fertilizer should be applied in the later period during one irrigation event to reduce
the leaching of nitrogen and raise fertilizer use efficiency． While available phosphorus was distributed
mainly in depth of 0 ～ 20 cm under drip emitter，due to its low migration with water． After three years
experiment，S1 had the lowest survival rate ( 56. 8%) ，and S3 got the highest ( 81. 1%) ，S2，S3 and
S4 gave higher fruit yields than other treatments significantly ( p ＜ 0. 05) ， which was around
900 kg /hm2，and it was close to the level in local farmland． The findings indicated that a sand-filled
niche beneath the drip emitter could be adopted for the reclamation of highly saline-sodic wasteland of
takyric solonetz． Considering the factors，including soil water-salt properties，soil nutrients distribution
and the growth of Lycium barbarum L． ，an SMP of － 10 kPa in the first two years and － 20 kPa from the
third year could be used to trigger drip irrigation．
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