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Sun Y.,Northwest University, China | Sun Y.,Shaanxi Provincial Land Engineering Construction Group Company Ltd | Sun Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Yan X.,Northwest University, China | And 4 more authors.
Emirates Journal of Food and Agriculture | Year: 2017

An experiment was conducted to verify how the grain yield and associated photosynthesis characteristics of wheat respond to seeding rate with cultivar replacement. Seven wheat cultivars released from 1940 to 2004 that were once widely grown on the Loess Plateau were grown in field experiments during the 2011-2012 growing season at the Changwu experiment station in China using three seeding rates (100, 250, and 350 seeds m-2), using a randomized complete block with a split-plot design and three blocks. The grain yield increased linearly with cultivar development in all seeding rate treatments, with annual genetic gains ranging from 0.65% to 1.29%. The cultivars released after the 1980s were less sensitive to seeding rate and had better population regulation. The improvements in the harvest index and thousand grain weights of the modern cultivars were significantly and positively correlated with the grain yield. The photosynthetic rate of the flag leaf and the leaf area index at anthesis consistently increased with cultivar replacement, contributing more to the thousand-grain weight and resulting in grain yield increases. Diffuse non-interceptance at anthesis resulted in opposite, stable trends with time. One reason to adapt modern cultivars for modern cultivation is their lower sensitivity to seeding rate. Thus, larger sinks for the grains and the optimization of plant types for light interception should be given greater consideration in dryland wheat breeding on the Loess Plateau.

Han J.,Shaanxi Province Real Estate Development Corporation | Han J.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Han J.,Engineering Research Center for Land Consolidation of Shaanxi Province | Xie J.,Engineering Research Center for Land Consolidation of Shaanxi Province | And 3 more authors.
Chinese Geographical Science | Year: 2012

This paper analyzed the water-retention mechanism of feldspathic sandstone (fine- (< 1 mm diam.) and gravel-sized (2.3 cm diam.) in Mu Us Sandy Land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on water retention in sandy land. The results showed that as the proportion of fine feldspathic sandstone in the sandy land soil increased, the soil texture changed from sand to silt loam, the capillary porosity gradually increased from 26.3% to 44.9%, and the soil saturated hydraulic conductivity decreased from 7.10 mm/min to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy land soil, playing the role of a 'water absorbent' and 'water retaining agent' in sandy land. Amendment with feldspathic sandstone can increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land soil and increase soil water retention. © 2012 Science Press, Northeast Institute of Geography and Agroecology, CAS and Springer-Verlag Berlin Heidelberg.

Jin L.,China Agricultural University | Jin L.,Heilongjiang Academy of Agriculture science | Hu K.,China Agricultural University | Deelstra J.,Institute for Agricultural and Environmental Research Bioforsk As | And 3 more authors.
Acta Agriculturae Scandinavica Section B: Soil and Plant Science | Year: 2014

Water scarcity and nitrate contamination in groundwater are serious problems in the North China Plain (NCP). The objective of this study was to compare the effects of farmer's practice and optimal water and nitrogen management on nitrate leaching, and water and nitrogen use efficiencies (WUE, NUE) during winter wheat season in the NCP. A winter wheat experiment with four treatments (traditional irrigation plus traditional fertilizer, W1N1; traditional irrigation plus optimal fertilizer, W1N2; optimal irrigation plus traditional fertilizer, W2N1; optimal irrigation plus optimal fertilizer, W2N2) was conducted from October 1999 to June 2001 in Beijing suburban. The soil-plant system, water and solute transport model was calibrated and validated based on the data collected from the experimental field, then the model was used to simulate the water movement, nitrogen (N) transport, and crop growth process. The results showed that the simulated soil water content, nitrate concentration in the soil profile, leaf area index, crop N uptake, and grain yield were all in good agreement with the measured data. The simulated results indicated that the improved management of water and fertilizer practice could increase crop yield, and reduce water drainage, nitrate leaching, and gaseous N loss compared to farmers' practice. WUE and NUE under improved practice were 1.36 kg m-3 and 34.9 kg kg-1N-1 in 2000, 1.07 kg m-3 and 31.5 kg kg-1N-1 in 2001, respectively. Compared to farmers' practice, the optimal management practice can save water about 4-19%, water drainage decreased 50-65%, N leaching reduced over 90% and gaseous N loss decreased about 70%, at same time leading to an increase in WUE and NUE by 10.6% and 10.3% in 2000, 64.5% and 98.3% in 2001, respectively. © 2014 Taylor & Francis.

Han J.,Shaanxi Provincial Land Engineering Construction Group Co. | Han J.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Liu Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Liu Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | And 2 more authors.
Journal of Geographical Sciences | Year: 2015

Depended on the analysis of ground snow situation, soil moisture loss speed and soil structure after planting crops of Mu Us Sandy Land remedied with feldspathic sandstone in the fallow period, it is concluded that feldspathic sandstone mixed with sand improved the sand stabilization in the governance of Mu Us Sandy Land in the fallow period. The sandy land remedied with feldspathic sandstone had big snow coverage, 25%–75% higher than normal sand; soil moisture losses slowed down, and moisture content rose by over 3 times; soil structure had been improved, and water stable aggregate content increased by 6.52%–18.04%; survival rate of protection forest increased to 85%; and ground flatness is less than 1%. The above conditions weakened sand rising conditions of Mu Us Sandy Land in the fallow period and formed two protective layers of snow cover and soil frozen layer under cold weather so as to prevent against wind erosion. © 2015, Science in China Press and Springer-Verlag Berlin Heidelberg.

Han J.,Shaanxi Land Construction Group Co. | Han J.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Han J.,Engineering Research Center for Land Consolidation | Zhang Y.,Shaanxi Land Construction Group Co. | And 2 more authors.
Land Use Policy | Year: 2014

Based on the relationship between land policy and land engineering, we defined the concept of 'land engineering' and its contents, and demonstrated the significance of the establishment of land engineering. On the one hand, the land policy guided the development of the land engineering. On the other hand, the land engineering is an important means to improve and execute the land policy. The contents of land engineering are summarized as follows: (1) conversion of non-agricultural land into agricultural land; (2) conversion of low standard use land into a high standard use land; (3) conversion of current land into human construction use; (4) conversion of polluted and damaged land into usable land. Our study provides scientific support for the efficient utilization of land resources. © 2013 Elsevier Ltd.

Li X.-M.,Shaanxi Land Engineering Construction Group | Li X.-M.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Li X.-M.,Engineering Research Center for Land Consolidation | Han J.-C.,Shaanxi Land Engineering Construction Group | And 5 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2014

Hysperspectral inversion of soil salinity was researched in the present paper with the chosen study object of typical semiarid area in North Shaanxi Province. The studying sites were selected, the hyperspectral data were collected, and the soil samples were taken back for experiment analysis. The reflectance of soils (R), the logarithm of the reciprocal of the reflectance (Log(1/R)) and the continual removed reflectance (Rcr) were used to research the soil salinity. The correlations between the hyperspectral character and soil salinity was studied to filter the characteristics bands. Then the partial least squares regression (PLSR) was used to study the inversion model of soil salinity with Matlab program, and the precision was compared with the verifying sites. The research result showed that the root mean square error (RMSE) of the inversion with Rcr was the least (1.253<1.367<1.575), and its precision was the best; the correlation between the predicted value and the measured value was well (r2=0.761), the trend line was near y=x. In conclusion, the quantificational inversion model with the variables of Rcr establised by PLSR was well, which will improve the survey efficiency of soil salinity.

Wang Y.-L.,Chinese Academy of Sciences | Wang Y.-L.,University of Chinese Academy of Sciences | Liu L.-C.,Chinese Academy of Sciences | Gao Y.-H.,Chinese Academy of Sciences | And 5 more authors.
Chinese Journal of Applied Ecology | Year: 2016

Water is a major limiting factor for plant growth in arid and semi-arid regions. To find out the main sources of water for two artificial sand-fixation plants (Caragana korshinskii and Artemisia ordosica), we analyzed the characteristics of hydrogen and oxygen stable isotopes in water molecules of rainfall, soil water and xylem water. To analyze water sources of these two plants, we used a direct comparison method and a multi-variate mixed linear model. The results showed that an equation of local meteoric water line in Shapotou was δD=7.83δ18O+5.64 (R2=0.91). The value for rainfall δ18O varied during plant-growing season, which was higher in the beginning and end of growing season, and lower in the peak of growing season. The value for soil water δ18O in the upper layers changed dramatically. The change range became smaller in the deeper soil layer. C. korshinskii had a greater efficiency (56.1%) in utilizing soil water in 40-80 cm soil layer. A. ordosica had a utilizing efficiency of 56.4% in 20-60 cm soil layer. A week after rain event, C. korshinskii and A. ordosica showed a higher efficiency in upper soil water. C. korshinskii showed an increase of 12.5% in utilizing soil water in 0-40 cm soil layer and A. ordosicas showed an increase of 10% in utilizing soil water in 0-20 cm layer. These results suggested that C. korshinskii and A. ordosica changed their water use strategy after large rainfall events, which might enable them to more easily adapt to arid environment. © 2016, Science Press. All right reserved.

Li Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Li Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Li Y.,Chinese Academy of Sciences | Cao Z.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | And 8 more authors.
Journal of Cleaner Production | Year: 2016

Climate change and human activities have affected ecological environment in recent decades. This paper investigates the ecological environment change of the Mu Us sandy land based on a combined analysis of land cover and normalized difference vegetation index (NDVI) change trends. The results show that land cover changed moderately during 1990-2010, and areas experienced conversion accounted for 10% of the total land surface. The NDVI values show an evident increase at about 0.0076 year-1 during 2000-2014. This rate is lower than that of Shaanxi-Gansu-Ningxia region (0.0117 year-1), but greatly exceeds those of the Three-North Shelter Forest and the upper reaches of the Yellow River. Four categories of grids have been identified for accurate ecological restoration through analyzing the ecological performance index mainly based on land cover and NDVI indicators. The ecological restoration projects laid important foundation for ecological reconstruction in the Mu Us, while the wetting trend has been major climatic factors in vegetation improvement since 2000 (R = 0.687, P ≤ 0.01). However, both field investigation and statistical data analysis indicate that the ecological restoration in the Mu Us are experiencing increasing challenges, due to the growing human activities and still fragile eco-environment. Therefore, this paper suggests that urban-rural development and coal exploitation in this region should give full consideration to the carrying capacity of water and land resources. Overall, the evolving 'science' of 'BIG DATA' on coupled human-environment system can help to reveal the dynamics of ecological environment, and contribute valuable information for decision making concerning natural resources management and urban-rural development. © 2016 Elsevier Ltd.

Liu Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Liu Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Yang R.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Yang R.,University of Chinese Academy of Sciences | And 5 more authors.
Land Use Policy | Year: 2014

Based on surveys on rural land-use change at village scale in Yucheng City, Shandong province, this paper presents how land-use change takes place in response to inhibitive institutional forces in light of an outmoded land ownership system and unreasonable land use rights administration, and discusses it in the broader social context of industrialization, rural depopulation, a dual-track land market, and land use legislation. Spatial comparison of land use maps interpreted from aerial photographs in different period unveils a decrease in arable land for farming, and an increase in rural settlements, facilities land and unused land. Despite rural depopulation, rural settlements area nearly tripled during 1967-2008. Nearly all newly gained non-agricultural land originated from farmland at the village fringe while formerly facilities land and unused land had been converted to residential use and it was abandoned later. Thus, the destructive farmland conversion from productive use to non-agricultural uses took place at multiple stages. Questionnaire survey of 1650 households in 48 villages in Yucheng City indicated that 41% of the households had multiple dwellings, even though some of them are not occupied or even ruined. This finding may damp the rosy picture of the reportedly slowdown in China's farmland reduction in recent years as these destructive changes are too small to detect from satellite imagery, and it will also provide a practical scientific basis for constituting more strict farmland protection objectives and strategies for China in the near future. In order to hold back the destructive conversion trend from farmland to non-agricultural uses, the authors argue that policy and institution innovation concerning land use and urban-rural development in China needs feature highly in the government's agenda. © 2013 Elsevier Ltd.

Li Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Li Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | Liu Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Liu Y.,Key Laboratory of Degraded and Unused Land Consolidation Engineering | And 3 more authors.
Land Use Policy | Year: 2014

The accelerated rural hollowing driven by vast and increasing out-migration of rural labors under urban-rural dual-track system has imposed huge obstacles on improving land use efficiency and coordinating urban-rural development in China. Taking Dancheng County in Henan Province as an example, this paper analyzes the status quo of rural hollowing and discusses two typical rural residential land consolidation and allocation (RRLCA) practices in traditional agricultural areas (TAAs) of China. The results show that, Dancheng experienced rapid rural hollowing characterized as the hollowing of rural industries, infrastructure, and residential population and settlements. However, Dancheng has considerable potential and the necessity of RRLCA, for the model-based estimation shows that the potential of increasing farmland by carrying out RRLCA was about 5649. ha. The two community-based RRLCA practices show positive effects on the improvement of local living conditions, increment of farmland area and development of rural industries. Their experiences, including self-organized rural planning, democratic decision-making, and endogenous institutional innovation may benefit future RRLCA. Overall, it indicates that promoting community-based RRLCA scientifically according to local conditions could provide an integrated platform for increasing farmland area, developing modern agriculture, promoting new countryside construction, and thus revitalize hollowed villages. On considering the limitations and obstacles of current initiatives, suggestions for future RRLCA in rural China have been put forward. © 2014 Elsevier Ltd.

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