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9篇 您的检索式:作者名="YaYong Luo"
    题名 作者 年代 出处 被引量
1Variation in soil water content to rainfall under Caragana microphylla shrub in Horqin Sandy Land显示文摘In order to investigate the spatio-temporal variability of soil water content to rainfall under Caragana microphylla shrub in Horqin Sandy Land,a plot of 25 m × 25 m,where there were 6 shrub canopies of C. microphylla,was sited for measuring soil water content at two soil layers of 0-20 cm (top layer) and 20-40 cm (lower layer). Soil water content was measured on the 1st,5th,10th and 15th day after a 42 mm rainfall in Naiman of Inner Mongolia. The results showed that soil water contents at both layers under C. microphylla shrub were gradually decreased after the rain. Soil water content at the top layer outside the shrub canopy was higher than that inside the shrub canopy within 5 days,and became similar inside and outside the shrub canopy on the 10th day after the 42 mm rainfall,and it was lower outside than that inside the shrub canopy on the 15th day. The soil water content at lower layer in the area without shrubs was higher than that under shrub canopy all along. All the measured values of soil water content can be fitted to a variogram model. There was significant autocorrelation of the values of soil water content between top layer and lower layer,except for the fourth measured values of soil water content at top layer. The range and spatial dependence of soil water content at top layer were lower than that at lower layer.Wang, ShaoKun Zhao, XueYong Qu, Hao Luo, YaYong Yun, JianYing 2010Journal of Arid Land2010,2,3:8
2Toward sustainable desertification reversion:A case study in Horqin Sandy Land of northern China显示文摘Desertification reversion is an interactive process involving climate, land use change, and water processes. In order to reveal the relationship between desertification reversion and these factors, we analyzed historical data on precipitation, air temperature, desertified land changes, underground water tables, and water body changes in Naiman County in the central part of Horqin Sandy Land. Our analysis showed that during 1961-2010 the annual precipitation fluctuated dramatically and has decreased fairly consistently in recent years. The air temperature increased by 0.50-1.25 °C, and the minimum temperature increased more obviously. The desertified land area increased from 42,300 km2 in 1959 to 62,000 km2 in 1985, and then declined to about 50,000 km2 in 2010. The underground water tables have been lowered by about 10 m in the past 30 years, and declined more rapidly in recent years. Desertified land is significantly related to the amount of total cropland, and underground water tables are significantly correlated with annual precipitation and the amount of irrigated cropland. Therefore, it is necessary to pursue sustainable desertification reversion without compromising the capacity for local development and restoration of degraded land, through application of appropriate management measures for improving water availability in this region.XueYong Zhao ShaoKun Wang YaYong Luo WenDa Huang Hao Qu Jie Lian 2015Research in Cold and Arid Regions2015,7,1:6
3An effective spray drift-reducing method for a plant-protection unmanned aerial vehicle显示文摘A spraying system for a plant-protection unmanned aerial vehicle(UAV)was designed to reduce spray drift.A custom low-speed wind tunnel was constructed to generate a wind speed ranging from 0 to 5.92 m/s.The results showed that the wind speed was attenuated with an increase in distance.To compensate for the attenuation,a linear-fitting model was adopted.Then,the relationship between the spraying pressure and atomization rate was analyzed,and a fuzzy algorithm was adopted to adjust the spraying angle and pressure according to the wind speed and its changing rate.Finally,an evaluation of the proposed system in the compensated wind tunnel was conducted,and the drift distance was reduced by 33.7%compared with the system without adjustment of the spraying angle and pressure.Yayong Chen Chaojun Hou Yu Tang Jiajun Zhuang Jintian Lin Shaoming Luo 2019International Journal of Agricultural and Biological Engineering2019,12,5:2
4Plant distribution at the mobile dune scale and its relevance to soil properties and topographic features显示文摘Xiaoan Zuo Halin Zhao Xueyong Zhao Yirui Guo Yulin Li Yayong Luo 2008Environmental Geology2008,,5:2
5Seasonal changes in the relationship between species richness and community biomass in grassland under grazing and exclosure, Horqin Sandy Land, northern China显示文摘How species diversity-productivity relationships respond to temporal dynamics and land use is still not clear in semi-arid grassland ecosystems. We analyzed seasonal changes of the relationships between vegetation cover, plant density, species richness, and above-ground biomass in grasslands under grazing and exclosure in the Horqin Sandy Land of northern China. Our results showed that in grazed and fenced grassland, vegetation cover, richness, and biomass were lower in April than in August, whereas plant density showed a reverse trend. Vegetation cover during the growing season and biomass in June and August were higher in fenced grassland than in grazed grassland, whereas plant density in April and June was lower in fenced grassland than in grazed grassland. A negative relationship between species richness and biomass was found in August in fenced grassland, and in grazed grassland the relationship between plant density and biomass changed from positive in April to negative in August. The relationship between the density of the dominant plant species and the total biomass also varied with seasonal changes and land use (grazing and exclosure). These results suggest that long-term grazing, seasonal changes, and their interaction significantly influence vegetation cover, plant density, and biomass in grasslands. Plant species competition in fenced grassland results in seasonal changes of the relationship between species richness and biomass. Long-term grazing also affects seasonal changes of the density and biomass of dominant plant species, which further affects the seasonal relationship between plant density and biomass in grasslands. Our study demonstrates the importance of temporal dynamics and land use in understanding the relationship between species richness and ecosystem function.XiaoAn Zuo XueYong Zhao TongHui Zhang ShaoKun Wang YaYong Luo Xin Zhou 2013Research in Cold and Arid Regions2013,5,2:2
6Desertification Reversion in Relation to Land Use Change and Climate in Naiman County, Inner-Mongolia, China显示文摘Analyses of desertified land and land use change in Naiman County of Inner-Mongolia showed that there was a fluctuated in-crease of rain-fed cropland in the period from 1951 to 1960, then decreased until the middle of the 1990's, then increased again, while irrigated cropland consistently increased. The woodland and build-up land consistently increased while grassland area de-creased. The area of water body increased from 1975 to 1995 and then decreased while river beach decreased. Wetland change fluctuated with a maximum of 303.53km2 in 1995 and a minimum of 62.08 km2 in 2002. Invasion of cropland into river beach does not only change land coverage on the beach, but also the hydrological process of the river systems and deeply influence wa-ter availability. The correlation between cropland and underground water table is negative and significant. Increase of irrigated cropland is the primary cause of water availability reduction. Water table reduction is negatively correlated to cropland. The total desertified land has decreased since 1975. A rapid increase occurred before 1959, but it is difficult to assess the change of deserti-fication due to lack of data from 1959 to 1975. Changes of different types of desertified lands were different. There is no signifi-cant correlation between land use and different types of desertified land, but there is a significant negative correlation between woodland and total desertified land. The correlation between grassland and total desertified land is positive and significant. There is a significant correlation between different land cover and key factors such as water body and annual precipitation, river beach and runoff, area of shifting dune and annual precipitation, and cropland and underground water table. Desertification reversion in Naiman County is fragile and will be even much more fragile due to population growth, rapid land use and climate change. This will lead to continued invasion of irrigated cropland into more fragile ecosystems and reduction of water availability.XueYong Zhao XiaoAn Zuo Gang Huang YingXin Huang ShaoKun Wang YaYong Luo WenDa Huang Hao Qu Wei Mao Jie Lian 2010Research in Cold and Arid Regions2010,2,1:2
7Photosynthesis of Digitaria ciliaris during repeated soil drought and rewatering显示文摘The ability of psammophyte photosynthesis to withstand and recover from severe droughts is crucial for vegetation stability in semi-arid sandy lands. The responses of gas exchange and chlorophyll fluorescence of an annual grass, Digitaria ciliaris, were measured through three soil drought and rewatering cycles. Results showed that the net photosynthesis rate(P n) decreased by 92%, 95%, and 63% at end of the three drought periods, respectively, water use efficiency(WUE) decreased by 67%, 54%, and 48%, while the constant intercellular CO2 concentration(C i) increased by 1.08, 0.88, and 0.45 times. During those three cycles, the trapping probability with no dark adaptation(F v′/F m′) decreased by 55%, 51%, and 9%, the electron transport per cross section(ET0′/CS0′) decreased by 63%, 42%, and 18%, and the dissipation per cross section(DI0′/CS0′) increased by 97%, 96%, and 21%. These results indicated that D. ciliaris was subjected to photoinhibition and some non-stomatal limitation of photosynthesis under drought. However, after four days of rewatering, its photosynthetic characteristics were restored to control values. This capability to recover from drought may contribute to making the plant's use of water as efficient as possible. Furthermore, the photosynthesis decreased more slowly in the subsequent drought cycles than in the first cycle, allowing D. ciliaris to enhance its future drought tolerance after drought hardening. Thus, it acclimatizes itself to repeated soil drought.YaYong Luo XueYong Zhao JingHui Zhang YuLin Li XiaoAn Zuo DianChao Sun 2015Research in Cold and Arid Regions2015,7,1:2
8Relationship between the haplotype distribution of Artemisia halodendron(Asteraceae) and hydrothermal regions in Horqin Sandy Land, northern China显示文摘The genetic diversity of Artemisia halodendron(Asteraceae), a constructive and dominant species in Horqin Sandy Land,was investigated to examine the genetic relationships with different hydrothermal regions in Horqin Sandy Land. We sequenced chloroplast DNA(cp DNA) fragments(trn L–F) of 243 plants from 10 populations across the Horqin Sandy Land.The analyses of cp DNA variation identified seven haplotypes. A low level of haplotype diversity(H_d=0.706) and nucleotide diversity(π=0.0013) was detected. Haplotypes clustered into two tentative clades. Low genetic differentiation among regions was consistently indicated by hierarchical analyses of molecular variance(AMOVA). Across the sampled populations, the haplotype distributions were differentiated with hydrothermal gradients.WenDa Huang XueYong Zhao YuLin Li YuQiang Li YaYong Luo 2018Research in Cold and Arid Regions2018,10,2:0
9ISSR analysis of Caragana microphylla(Leguminosae) in different temperature gradients显示文摘Caragana microphylla is the most dominant and constructive shrub species in the Horqin Sandy Land of northeastern China. We evaluated the level of genetic variation within and among C. microphylla populations sampled from three different temperature gradients in the Horqin Sandy Land by using inter-simple sequence repeat polymorphism(ISSR) molecular markers. The results show that eight ISSR primers generated 127 bands, of which 123(96.85%) were polymorphic. At the species level, genetic diversity was relatively high(P = 96.85%, h = 0.3143, I = 0.4790). The highest genetic diversity was observed in the Subp6 population from low temperature regions, whereas the lowest diversity was found in the Subp2 population from high temperature regions. Six populations of C. microphylla clustered into two clades. These results have important implications for restoring and managing the degraded ecosystem in arid and semi-arid areas.WenDa Huang XueYong Zhao YuLin Li YuQiang Li YaYong Luo Jing Feng Na Su 2015Research in Cold and Arid Regions2015,7,1:0
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