Degradation of the Black Soil Region of NE China by Excessive Erosion.

The 1.03 million km² black soil region of China (9.3% of the total area) is located in the northeast part of the country. The topography of the region is characterized by gentle (mainly 0 ~ 5°), long slopes (mainly 750 m). The dominant soil is classified as Udic Argiboroll. The landuse is primarily soybean production (83% by area). This region produces around 17% of the grain (37% of soybean and 57% of corn) and is the only region in China that exports grain. As such its food production is vital to the food security of China. This region has been in production for a very short time, about 70 years, yet, due to intense mechanized cultivation, soil erosion has already become a very serious problem with gully erosion being a significant contributor. Gully densities ranging from 0.33 km/km² to 0.9 km/km² have been reported.  Soils in the NE Black Soil region are degrading rapidly and erosion has already affected crop yield in many areas. There needs to be a plan to adopt conservation tillage and erosion control practices to alleviate further degradation. Site characteristics that result in ephemeral gully erosion (EGE) need to be quantified and methods of controlling EGE need to be developed and implemented. A collaborative project has been established between USDA-ARS and scientists with Beijing Normal University and the Institute of Soil and Water Conservation through the Joint Sino-USDA Center. Research projects on developing agricultural production systems that provide environmental sustainability are being evaluated and collaborative efforts in assessing EGE are underway.