Time filter

Source Type

Liu Y.,CAS Yantai Institute of Coastal Zone Research | Xu Z.,State Power Environmental Protection Research Institute | Duffy R.,CAS Yantai Institute of Coastal Zone Research | Chen W.,Institute of Chemical Defence | And 3 more authors.
European Journal of Soil Biology | Year: 2011

Stable isotopic characteristics of plant water represent an integrated response of root systems to water sources with different isotopic signatures. Analysis of these signatures can help to identify many ecological processes involved in the uptake, transport and utilization of different water sources. In August 2003, we collected soil water samples throughout the soil profile from a subalpine shrub ecosystem in Wolong Nature Reserve, West China, along with stem water samples from the two dominant shrub species, Quercus aquifolioides and Salix luctuosa. Stable isotope contents of the different water samples were determined in conjunction with rootlet biomass distribution of each species and soil water content throughout the soil profile. Results indicated that these subalpine non-phreatophytic shrubs utilized soil water primarily from the top 30 cm of the soil profile. Water uptake patterns were significantly positively correlated with rootlet biomass distribution as well as the soil water content profile. Hence, the two shrubs could play an important role in keeping rainwater from entering river channels quickly, thereby reducing risk of flooding. © 2011.

Yang W.,Nanjing University | Yang W.,Huazhong Agricultural University | Liu F.,Nanjing University | Liu F.,Water Resources Research Institute of Shandong Province | And 3 more authors.
Agroforestry Systems | Year: 2013

We analyzed the growth and photosynthetic responses of Canarium pimela K. D. Koenig (Chinese black olive) and Nephelium topengii (Merr.) H. S. Lo. (Hainan shaozi) to a light gradient to recommend better procedures for optimizing seedling establishment and growth of both species in restoration and agroforestry practices. One-month-old seedlings were exposed to four irradiance levels (46, 13, 2 and 0. 2 % full sunlight) inside shade cloth covered shadehouses for 1 year. With decreased sunlight both species displayed trends of decreased relative growth rate (RGR) and leaf area (LA), and increased specific leaf area and leaf area ratio (LAR). The mean values of light-saturated net photosynthetic rate (Pmax) in 46 and 0. 2 % full sunlight were 10. 11 and 3. 44 μmol CO2 m-2 s-1 for C. pimela and 6. 26 and 3. 47 μmol CO2 m-2 s-1 for N. topengii, respectively. C. pimela had higher RGR in 46 and 13 % full sunlight than in 2 and 0. 2 % full sunlight. Differences in growth rates can be explained by the different values of LA, LAR and leaf mass ratio, as well as by the different values of photosynthetic saturation irradiance and net photosynthetic rate (Pmax) between the two species. Both morphological and physiological responses to shading indicate N. topengii could be rated as "very shade-tolerant," while C. pimela could be rated as "intermediately shade-tolerant". © 2012 Springer Science+Business Media B.V.

Zhao Y.,Water Resources Research Institute of Shandong Province | Zhao Y.,Shandong Provincial Key Laboratory of Water Resources and Environment
Material Science and Environmental Engineering - Proceedings of the 3rd annual 2015 International Conference on Material Science and Environmental Engineering, ICMSEE 2015 | Year: 2016

Runoff nutrient monitoring of water and soil loss usually adopts field acquisition followed by laboratory analysis which is very complex. To verify the reliability of the rapid nutrient measurement method of Ion Selective Electrode (ISE) in water and soil loss monitoring, the nitrogen ammonia ISE as an example was compared with traditional Nessler reagent spectrophotometry by simulating rainfall. Studies were conducted with regard to accuracy, anti-ion interference and migration rule in slope runoff. Experimental results showed that: With confidence level of 95%, results of the two methods are no significant difference; the maximum value of measurement range of ISE is 1000 mg/L and that of spectrophotometric method is 2 mg/L; ISE can automatically resist ion interference; when the power function model is used to simulate ammonia nitrogen migration in slope runoff, the fitting coefficient of measurement value of electrode method is 0.9537 and that of spectrophotometric method is 0.9305. © 2016 Taylor and Francis Group, London.

Tian S.G.,Water Resources Research Institute of Shandong Province
Advanced Materials Research | Year: 2013

Effects of promoting rainwater infiltration and the impact factors of concave herbaceous field were analyzed in urban area of Jinan at different scenarios of designed rainfall frequencies, greening rates and concave depths. The capability of rainwater storage and infiltration is correlated negatively with designed rainfall frequency, and positively with concave depth, greening rate and soil infiltration coefficient. The results show that when the ratio of green space is 30% and the concave depth is 100mm, the rainwater collection rate of concave herbaceous field is 76.55% and 63.45% respectively under the rainfall of 1- year and 3- years return periods. © (2013) Trans Tech Publications, Switzerland.

Ma L.,Water Resources Research Institute of Shandong Province | Sui L.,Zhanhua Land Resources Bureau
Applied Mechanics and Materials | Year: 2012

Sediment diverted from the Lower Yellow River is crucial for irrigation district sustainable development. As a complex problem, spatial distribution of sediment in district is related with natural geographical environment, incoming water amount and sediment concentration, methods of treatment, engineering facilities. Analysis of sediment distribution is the precondition for sediment utilization, transportation and treatment. As Bojili irrigation district for example, the paper analyzed sediment siltation characteristics in desilting branch, main canal, branch canal and field ditch with long term observed data from 1985 to 2009. Proportions of sediment siltation in different parts of irrigation system were calculated and difference of seasonal siltation in desilting branch was discussed. Besides, the paper proposed effective suggestions about reducing sediment siltation and improving transportation with long distance. © (2012) Trans Tech Publications, Switzerland.

Discover hidden collaborations