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Physiological Responses of Halophyte Suaeda salsa to Water Table and Salt Stresses in Coastal Wetland of Yellow River DeltaSoil salinity and waterlogging are two major environmental problems in estuarine wetlands. The objective of this study was to investigate the effects of salt stress, water table, and their combination on growth, chlorophyll content, antioxidant system, and ion accumulation in Suaeda salsa plant, which is the pioneer plant in coastal wetland of the Yellow River Delta (YRD). The results showed that plant height, number of branches, and biomass were significantly affected by water table and salt stress. With enhanced salt stress, the ratio of leaf to total biomass increased and the ratio of root to total biomass decreased. The contents of Chl-a, -b, Chl-a?+?b, and carotenoids (Car) decreased significantly with increasing soil salinity and the water table level. Salt stress enhanced the activity of superoxide dismutase (SOD) and catalase (CAT), but reduced the content of protein. With the lowering water table level, the activity of CAT and protein content increased, and activity of SOD decreased. Na+ and Cl- content were up-regulated with increasing salt stress (NaCl), whereas, the contents of other cations (K+, Ca2+, and Mg2+) and anions (SO(4)(2-) and NO(3)(-)) were decreased. In summary, the results indicated that the S. salsa plants could adapt to the adverse soil environments through modifying their growth and physiology status at the highly saline and intertidal zone, such as the YRD estuarine wetlands, and also could be used as a bio-reclamation plant to decline the high salt in saline soils.
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The Role of Agriculture in a Modernizing SocietyChina's success in addressing food
 problems after adopting the reforms in 1978 has been nothing
 less than remarkable. Grain output (rice, wheat and maize)
 has almost doubled and most hunger has been eliminated. Ever
 since China embarked on its reform agenda more than 30 years
 ago, its economic growth and poverty reduction have been
 nothing less than remarkable. Agriculture has been an
 important contributor to these developments. Since 1978,
 China has almost doubled its cereal production (rice, wheat
 and maize) and it is now feeding 1.3 billion people, or 20
 percent of the world's population, while having less
 than 11 percent of the world s agricultural land and less
 than 6 percent of its water. New challenges are presenting
 themselves for China's agriculture, and old ones are
 resurfacing. High (land saving) Total Factor Productivity
 (TFP) growth and increasingly open domestic and
 international markets, combined with grain self-sufficiency
 targets, a multitude of very small, fragmented production
 structures, and distorted land and labor markets have
 defined Chinese agriculture over the past three decades. The
 relative importance of agriculture s three problems in
 policymaking thus evolves during the course of development
 away from the food to the farm and field problems. This
 shift has however recently been compounded by a resurgence
 of the food problem, as global supplies struggle to keep up
 with demand. China's agriculture anno 2030 will be
 predominantly a modern commercial smallholder agriculture
 that ensures self-sufficiency in cereal food (rice and
 wheat), but not in cereal feed (maize and soybeans). The
 sector will maximize rural employment opportunities in labor
 intensive high value agricultural products and act as a
 diligent custodian of its precious natural resources.