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1

Abundance and breeding ecology of Brown Accentors Prunella fulvescens in Lhasa, Tibet

100%
Lu X.
Acta Ornithologica
|
2006
|
tom 41
|
nr 2
2

The annual cycle of molt in the Cape hare Lepus capensis in Northern China: pattern, timing and duration

100%
Lu X.
Acta Theriologica
|
2003
|
tom 48
|
nr 3
Molt is an important life history event for mammals occurring in temperate and cold zones. In the present paper, I investigate the pattern, timing and duration of seasonal molts of the Cape hares Lepus capensis Linnaeus, 1798 in northern China, by tracing and scoring the process of each molt quantitatively. All the seasonal molts in both overwintering and juvenile hares went through a similar order: midback (together with nape), flanks, belly, upper tail, and legs. Yet, there was a relatively confused pattern of replacement during the heaviest molting period of overwintering hares, compared to a relatively uniform pattern among juvenile hares. Overwintering hares experienced a spring and a fall molt. The fall molt was already initiated prior to completion of the spring molt and had a relatively short duration. Juveniles born early in the year (before July), before their fall molt, had undergone a postnatal molt, but those born late (July to September) had not. The juvenile fall molt had already begun when the postnatal molt was at its later stages. These facts suggest that the time budget for fall molt is tight and seasonally constrained. The timing and duration of molts in the overwintering and early-born juvenile hares were independent of indi­vidual age. Among overwintering hares, both sexes started spring molt synchronously, but the females were behind the males in late period of this molt and consequently further delayed throughout subsequent fall molt. This may be related to a higher cost of reproduction in females. No sexual difference was found in the molting progress of juvenile hares.
3

Body weights of the Cape hare Lepus capensis in the northern China

100%
Lu X.
Acta Theriologica
|
2000
|
tom 45
|
nr 2
This paper analyzed body weights of the Cape hare Lepus capensis Linnaeus, 1758 in northern China during 1990-1993. Body weight of the hares increased faster in the first five months of life. The juveniles with the same eye lens weight weighed less in spring-summer than in autumn, in the southern region than in the northern. The overwintering females increased weight with reproduction, the older of which gained more, In autumn-winter, body weights of adult females and males in the whole study region were 2.29 ± 0.05 and 2.11 ± 0.06 kg respectively. Body weight of the over­wintering hares varied seasonally. At the beginning of the breeding season female was the lightest while male the heaviest, and then female became heavier and male lighter. Regardless of age, area and season, females were usually heavier than males.
4

Breeding biology of Rock Sparrows Petronia petronia in the Tibetan plateau, with special reference to life history variation across altitudes

63%
Li S., Lu X.
Acta Ornithologica
|
2012
|
tom 47
|
nr 1
The Rock Sparrow Petronia petronia has been well studied with respect to reproductive biology at low-altitude in Europe, but not at high altitudes. This study presents the information on a Rock Sparrow population breeding in an alpine meadow at 3400 m altitude and compares the life history traits with their lower-altitude counterparts studied in Europe. The birds are resident all year round in this area. Nests of Rock Sparrows tended to cluster and were mainly located in abandoned burrows of the Ground Tit Parus humilis. Pairs were monogamous and territorial behaviors were absent, which differed from European populations, where Rock Sparrows show a series of mating systems and display strong territoriality around the nest site. Egg-laying took place between late May and late June, with every pair making a single nesting attempt. Clutch size averaged 5.1 ± 0.9, incubation undertaken by female only lasted 12.7 ± 0.8 days, and young in the nest were fed by both parents for 19.9 ± 0.7 days. Breeding success, measured as the proportion of nests with at least one fledgling, was 89%. Compared to their lower-altitude populations studied in Europe, the high-altitude Rock Sparrows start breeding later, experience a shorter breeding season, produce fewer but bigger eggs, and have a longer nestling period. Such a life history strategy that allows birds to allocate more energy into individual offspring should be adaptive to the harsh high-altitude conditions.
5
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Climate response of Salix oritrepha growth along a latitudinal gradient on the northeastern Tibetan Plateau

51%
Lu X., Sigdel S. R., Dawadi B., Wang Y.
Dendrobiology
|
2019
|
tom 81
6

Comparison of soil microbial biomass and enzyme activities among three alpine grassland types in Northern Tibet

51%
Lu X., Fan J., Yan Y., Wang X.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 2
Soil microbial biomass and enzyme activities have an important influence on nutrient cycling. The temporal variation in soil microbial biomass C, N, and enzyme activities during the growing season were determined under three different alpine grasslands in Northern Tibet. The results showed that soil microbial biomass C, and N contents and enzyme activities of the alpine meadow (AM) and the alpine meadow steppe (AMS) sites were much higher than those of the alpine steppe (AS) site. Soil microbial biomass C, N variations were not significantly correlated with the soil temperature and moisture, except that microbial biomass N seemed associated with the microsite where soil temperature was higher. Our results demonstrate that soil temperature was one of most important factors explaining the seasonal variation of microbial biomass N, but how the alpine grassland ecosystem's type affects microbial biomass C, N and enzyme activity are still needed to be clarified by determining other correlative ecological factors and covering prolonged observation periods.
7

Evaluating health hazards of harmful metals in roadway dust particles finer than 100 μm

51%
Shi D., Lu X., Wang Q.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 6
Pollution degrees and health hazards of harmful metals in roadway dust particles finer than 100 μm in various functional areas in Xi’an, China were investigated in our study exploring the impact of land use methods on the environment. X-ray fluorescence spectrometry was used to measure the content of harmful metals, and their pollution degrees were assessed by using the geoaccumulation index and Nemerow synthetic pollution index. The health risks of harmful metals to local residents were judged using the U.S. EPA health risk model. The present study reveals that Co, Cr, Pb, Cu, and Zn in the samples were 2.1-6.3, 1.9-4.8, 2.1-9.7, 1.1-4.6, and 0.9-13.0 times the corresponding background contents of local soil, respectively. Due to the influence of local land use and the diversity of sources, harmful metals in the various functional areas have different variation characteristics. The assessment results show that Ni, Mn, and V were unpolluted, while Co, Cr, Pb, Cu, and Zn presented pollution in different degrees. The analyzed harmful metals were moderately polluted in park and traffic areas, while in residential and educational areas were heavily polluted. The non-carcinogenic hazards of all measured harmful metals were within the safe range, and the cancer hazards of Co, Cr, and Ni were in the acceptable range.
8

Comparison of spatial interpolation methods based on rain gauges for annual precipitation on the Tibetan Plateau

51%
Zhang X., Lu X., Wang X.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 3
Accurate precipitation data are of great importance for environmental applications. Interpolation methods are usually applied to afford spatially distributed precipitation data. However, due to the scarcity of rain gauges, different spatial interpolation methods may result in deviations from the real spatial distribution of precipitation. In this study, three different interpolation methods were investigated with regard to their suitability for producing a spatial precipitation distribution on China’s Tibetan Plateau. Precipitation data from 39 rain gauges were spatially interpolated using ordinary kriging, cokriging with covariates as elevation (Cok-elevation), and cokriging with covariates as tropical rainfall measuring mission (Cok-TRMM). The results showed that the mean absolute error (MAE), mean relative error (MRE), and root mean square error (RMSE) for Cok-TRMM amounted to 103.85 mm, 0.32, and 134.50 mm, respectively. These numbers were lower than the figures for ordinary kriging (MAE 111.01 mm, MRE 0.34, RMSE 144.86 mm) and Cok-elevation (MAE 111.43 mm, MRE 0.34, RMSE 144.35 mm). In addition, the correlation coeffi cient between observed and predicted values of Cok-TRMM (r² = 0.53) was higher than that for ordinary kriging (r² = 0.46) and Cok-elevation (r² = 0.46). Our results demonstrate that Cok-TRMM is more effective at producing a spatial precipitation distribution on the Tibetan Plateau and can serve as a new spatial interpolation method for precipitation in data-scarce regions.
9

Nesting and cooperative breeding behaviours of a high-altitude babbler, Tibetan Babax Babax koslowi

51%
Lu X., Ma X., Fan L.
Acta Ornithologica
|
2007
|
tom 42
|
nr 2
181-185
10

Preparation and Cu (II) adsorption characteristics of carboxymethyl cross-linked sewage sludge

51%
Wang T., Zhang W., Lu X.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 2
Sewage sludge was cross-linked with epichlorohydrin to increase its mechanical strength and applicability as an absorbent material. We investigated the effect of the conditions of the cross-linking reaction on the mechanical strength and Cu (II) adsorption capacity of epichlorohydrin cross-linking sewage sludge (ECS). Experimental results showed that cross-linking can raise signifi cantly the mechanical strength of sewage sludge. To improve the adsorption capacity of ECS, carboxymethyl cross-linked sewage sludge (CCS) with maximal adsorption capacity (65mg/g) for Cu (II) was synthesized from ECS by using chloroacetic acid as the etherifi cation agent. The experimental results showed that the adsorption properties of CCS for Cu (II) could best be described by the pseudo-second order model and Langmuir model, and the adsorption mechanism was ion exchange. Our data suggest that CCS is a promising absorbent for removal of heavy metals from wastewater.
11

The impact of climate change and human activity on net primary production in Tibet

51%
Qin X., Sun J., Liu M., Lu X.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 5
The Tibetan Plateau has faced environmental degradation in recent years due to intensified human activity and climate change. In this study, the dynamics of net primary production (NPP), annual mean temperature (AMT), annual mean precipitation (AMP), number of animals (NA), number of rural laborers (NRL), and animal husbandry (AH) were analyzed and the response of NPP to climate and human activity explored. The results show that NPP was increasing gradually from northwest to southeast and is similar to the distribution of AMP. In addition, NA, NRL, and AH cluster around Lhasa. Moreover, AMP had a negative correlation with NPP in Tibet while AMT has a positive effect on NPP. Moreover, because of the large number of livestock there is a negative relationship between NA and NPP in most Tibetan regions. Furthermore, it was found that human activity made a higher contribution to NPP in Tibet (24.73%) than climate factors (17.28%). It is, therefore, necessary to further explore the relationship between human activity and the vegetation dynamic in the region.
12

Jasmonic acid regulates the ascorbate–glutathione cycle in Malus baccata Borkh. roots under low root-zone temperature

51%
Li J., Lu X., Ma H., Lyu D.
Acta Physiologiae Plantarum
|
2017
|
tom 39
|
nr 08
13

Low-carbon development of the construction industry in China’s pilot provinces

45%
Du Q., Lu X., Yu M., Yan Y., Mu M.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 4
14

Leaf litter decomposition in three subalpine forests along an elevation gradient in Tibet

45%
Fan J., Zhang X., Lu X., Yan Y., Wang X.
Polish Journal of Environmental Studies
|
2014
|
tom 23
|
nr 4
Litter decomposition is a fundamental ecosystem process, and climate and litter chemistry strongly control rates of litter decay. In this work, three forests along an elevation gradient on the eastern slope of Sergyemla Mountain were selected to compare litter decomposition and chemical fraction loss rates, and further to evaluate the effects of environmental factors and litter chemistry on the litter decomposition process. The leaf litter decomposition coefficient of the mixed conifer and broadleaf forest (MCBF, 3,169 m a.s.l.), sclerophyllous evergreen broadleaf forest (SEBF, 3,453 m a.s.l.), and subalpine dark coniferous forest (SDCF, 3,957 m a.s.l.) sites were 0.04, 0.03, and 0.02 month-1, respectively. The litter mass loss at the MCBF site significantly correlated with litter quality, but that of the SEBF and the SDCF sites did not. In addition, there was a significant positive relationship between the litter mass loss and temperature along the elevation gradients. This study demonstrates that the litter decomposition rate decreases with increasing altitude along the elevation gradient. Climate is the key factor influencing litter decay across environmental gradients, but litter quality also affects decomposition rates in low-elevation forests.
15

Morphology of two Eschaneustyla species (Ciliophora, Urostylida), with notes on morphogenesis of Eschaneustyla lugeri

45%
Deng Y., Lu X., Li J., Ba S., Paiva T. S.
Acta Protozoologica
|
2018
|
tom 57
|
nr 2
16

Relationships between soil nutrients and plant diversity in riparian woodlands along the middle and lower reaches of the Yellow river, China

39%
Zhao Q., Xu S., Tang Q., Lu X., Wang S., Ji X., Ding S.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 3
17

Molecular characterization and evolutionary origins of farinin genes in Brachypodium distachyon L.

33%
Subburaj S., Luo N., Lu X., Li X., Cao H., Hu Y., Li J., Yan Y.
Journal of Applied Genetics
|
2016
|
tom 57
|
nr 3
18

Assessing the suitability of habitat for wintering Siberian cranes (Leucogeranus leucogeranus) at different water levels in Poyang lake area, China

27%
Chen B., Cui P., Xu H., Lu X., Lei J., Wu Y., Shao M., Ding H., Wu J., Cao M., Liu G.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 1
Poyang lake area (1000–3246 km²) is the most important wintering ground for the globally critically endangered Siberian crane (Leucogeranus leucogeranus). More than 98% of the Siberian crane population overwinters in Poyang lake area. Remote-sensing and the spatial analysis tools of geographic information system (GIS) technology were used to assess the suitability of the habitat for wintering Siberian cranes in Poyang lake area at different water levels. The results demonstrated that as the water level increased within the range of 7.93–12.16 m, the area of unsuitable habitat increased gradually, but the areas of good, fair and poor habitat decreased. When the water level reached 12.16 m, good habitat for Siberian cranes covered an area of only 3005 ha, which is only 0.93% of the area of the total lake area. When human disturbance factors including vehicles, fishing and construction activities were added to the analysis of the current distribution of Siberian crane habitat, the results again indicated that the area of good habitat decreased with an increase in water level within the range of 7.93–12.16 m. Additionally, the areas of good habitat occurred primarily in the region of two national nature reserves, which are the Poyang Lake National Nature Reserve and the Nanjishan National Nature Reserve. Our study provides important data and an important theoretical basis for water level management and nature reserve construction in Poyang lake area.
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