Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Chine → 2008 → Experimental Study of Conservation Tillage in Thenorth of Mu Us Sandy Land

Northwest University of Science and Technology (2008)

Experimental Study of Conservation Tillage in Thenorth of Mu Us Sandy Land

LeiJinYin

Titre : Experimental Study of Conservation Tillage in Thenorth of Mu Us Sandy Land

Auteur : Lei Jin Yin

Grade : Doctoral Dissertation 2008

Université : Northwest University of Science and Technology

Résumé
In recent years, study about wind-induced desertification, which focused on wind erosion control on farmland in north China, got more and more concern due to the dust storm occurred frequently. Some research indicted that the farmland is one of main sources of wind erosion and dust storm. And it is also the weakness links of controlling wind erosion in our country. So, the farmland has been become the main research object and frontiers for controlling wind erosion. The sandy area in the north of Jingbian County is farming-pastoral interlaced zone, where ecological environment is fragile. Furthermore, traditional tillage makes no cover on soil in winter and spring, which enhances soil drying and wind erosion. So, using conservational tillage technology instead of traditional tillage to get high yield and control wind erosion is an effective way to develop ecological agriculture, control desertification, realize sustainable agriculture development, and improve local ecological environment.This paper was based on the survey of climate and soil nutrients changes in the past 20 years in the north windy desert area, Jingbian County. Field observation was conducted at Yangqiaopan Demonstration Farm, Jingbian Agriculture Bureau. Four tillage measurements were investigated : no tillage, residue mulching, film mulching, and traditional tillage for corn. Based on successful introduction of winter wheat, investigation of no tillage, film mulching, and traditional tillage for winter wheat were conducted. Protection effects against wind of different tillage measurements were tested in wind tunnel. Combined the field observation, wind tunnel simulation, and statistics methods, the soil characteristics, water and fertilizer using efficiency, economy profits, and wind control benefit under conservational tillage were systematically investigated. Main results lie below :(1) Strong wind, dry and cold weather often occurred simultaneously in study area, the long term average climate erosion index here is 92.8.The potential wind erosion danger in this area is high. Compared the soil nutrient at two different periods of 1983 and 2003 , it is proved that the proportion of soil fertilizer of Class1 and Class2 decreased 1-2%, Class5 and Class6 increased 5-7%. So, we can see that wind erosion is serious in the study site.(2) Corn conservational tillage improved soil characteristics, water and fertilizer using efficiency, and economy profits.Soil temperature under film mulching, no tillage, and residue mulching was not sensitive to air temperature, and relatively stable throughout the entire crop growing season. But soil temperature under traditional tillage was very sensitive to air temperature. Soil bulk density Compared to traditional tillage, no tillage and residue mulching reduced soil bulk density of 0-20 cm layer, and film mulching increased it. But, no tillage and residue mulching increased bulk density of 20-40 cm layer. The soil water content in 0-60 layer under film mulching, residue mulching, and no tillage were 10.88 mm, 6.26 mm, and 5.08 mm higher than traditional tillage, respectively. No tillage increased the soil nutrients stratification ratio. Organic matter, total N, and available K increased with cultivation time under all tillage measurements, and increased faster under no tillage. Available N and total P decreased with cultivation time, slower under no tillage. WUE under no tillage, residue mulching, and film mulching were 13.3%, 8%, and 22.0% higher than traditional tillage, respectively ; N, P fertilizer using efficiency were 61%, 23%, and 60% higher, respectively ; crop yield were 4.44%, 13.14%, and 19.26% higher, respectively. Economy profits were according to this sequence : no tillage>residue mulching>traditional tillage>film mulching. Though introduction experiment proved that winter wheat can be planted in this area.

Mots clés : Mu Us Sandy Land Farming-Pastoral Interlaced Zone Soil Wind Erosion Conservation Tillage

Présentation (Dissertationtopic)

Page publiée le 6 mai 2013, mise à jour le 9 janvier 2018