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Potato absorption and phytoavailability of Cd, Ni, Cu, Zn and Pb in sierozem soils amended with municipal sludge compost

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Journal of Arid Land 2018年第4期10卷 638-652页

作者： LIU Zheng NAN Zhongren zhao chuanyan YANG Yang College of Earth and Environmental Sciences Lanzhou University State Key Laboratory of Grassland and Agro-Ecosystems Lanzhou University

Effects of sludge utilization on the mobility and phytoavailability of heavy metals in soil-plant systems have attracted broad attention in recent years. In this study, we analyzed the effects of municipal sludge compost （MSC） on the solubility and pIant uptake of Cd, Ni, Cu, Zn and Pb in a soil-potato system to explore the mobility, potato plant uptake and enrichment of these five heavy metals in sierozem soils amended with MSC through a potato cultivation trial in Lanzhou University of China in 2014. Ridge regression analysis was conducted to investigate the phytoavailability of heavy metals in amended soils. Furthermore, CaC12, CH3COONH4, CH3COOH, diethylene triamine pentacetic acid （DTPA） and ethylene diamJne tetraacetic acid （EDTA） were used to extract the labile fraction of heavy metals from the amended soils. The results show that the MSC could not only improve the fertility but also increase the dissolved organic carbon （DOC） content of sierozem soils. The total concentrations and labile fraction proportions of heavy metals increase with increasing MSC percentage in sierozem soils. In amended soils, Cd has the highest solubility and mobility while Ni has the lowest solubility and mobility among the five heavy metals. The MSC increases the concentrations of heavy metals in the root, stem, peel and tuber of the potato plant, with the concentrations being much higher in the stem and root than in the peel and tuber. Among the five heavy metals, the bioconcentration factor value of Cd is the highest, while that of Ni is the lowest. The complexing agent （DTPA and EDTA） extractable fractions of heavy metals are the highest in terms of phytoavailability. Soil properties （including organic matter, pH and DOC） have important impacts on the phytoavailability of heavy metals. Our results suggest that in soil-potato systems, although the MSC may improve soil fertility, it can also increase the risk of soils exposed to heavy metals.

关键词： municipal sludge compost amended soils heavy metals mobility ridge regression phytoavailability

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Characteristics of Caragana korshinskii and Hippophae rhamnoides stemflow and their significance in soil moisture enhancement in Loess Plateau, China

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Journal of Arid Land 2014年第1期6卷 105-116页

作者： ShengQi JIAN chuanyan zhao ShuMin FANG Kai YU State Key Laboratory of Grassland and Agro-Ecosystems School of Life SciencesLanzhou University College of Resource and Environmental Sciences Gansu Agricultural University Ministry of Education Key Laboratory of Western China Environmental Systems Lanzhou University

Stemflow of xerophytic shrubs represents a significant component of water replenishment to the soil-root system and influences water utilization of plant roots at the stand scale,especially in water-scarce semi-arid *** stemflow of two semi-arid shrubs(Caragana korshinskii and Hippophae rhamnoides)and its effect on soil moisture enhancement were evaluated during the growing season of 2011 in the semi-arid loess region of *** results indicated that stemflow averaged 12.3%and 8.4%of the bulk precipitation for *** and ***,*** stemflow increased in a linear function with increasing rainfall *** relationship between funneling ratios and rainfall suggested that there existed a rainfall depth threshold of 11 mm for both *** and *** funneling ratios were 156.6±57.1 and49.5±30.8 for *** and ***,respectively,indicating that the canopy architecture of the two shrubs was an effective funnel to channel stemflow to the root area,and *** showed a greater potential to use stemflow water in the semi-arid *** individual rainfall events,the wetting front depths were approximately 2 times deeper in the rooting zone around the stems than in the bare area outside canopy for both *** and ***,soil water content was also significantly higher in the root area around the shrub stem than in the area outside the shrub *** confirms that shrub stemflow conserved in the deep soil layers may be an available moisture source for plant growth under semi-arid conditions.

关键词： precipitation stemflow funneling ratio rainfall intensity Anjiapo catchment

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Effect of vegetation on soil water retention and storage in a semi-arid alpine forest catchment

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Journal of Arid Land 2013年第2期5卷 207-219页

作者： Chao WANG chuanyan zhao ZhongLin XU Yang WANG HuanHua PENG College of Resources and Environmental Sciences Lanzhou University School of Life Sciences Lanzhou University College of Resources and Environmental Sciences Xinjiang University

The runoff generated from mountainous regions is recognized as the main water source for inland river basins in arid environments. Thus, the mechanisms by which catchments retain water in soils are to be understood. The water storage capacity of soil depends on its depth and capacity to retain water under gravita- tional drainage and evapotranspiration. The latter can be studied through soil water retention curve （SWRC）, which is closely related to soil properties such as texture, bulk density, porosity, soil organic carbon conteMt, and so on. The present study represented SWRCs using HYDRUS-1D. In the present study, we measured pl^ysical and hydraulic properties of soil samples collected from Sabina przewalskii forest （south-facing slope with highest solar radiation）, shrubs （west-facing slope with medium radiation）, and Picea crassifolia forest （north-facing slope with lowest radiation）, and analyzed the differences in soil water storage capacity of these soil samples. Soil water content of those three vegetation covers were also measured to validate the soil water storage capacity and to analyze the relationship between soil organic matter content and soil water content. Statistical analysis showed that different vegetation covers could lead to different soil bulk densities and differences in soil water retention on the three slope aspects. Sand content, porosity, and organic carbon content of the P. crassifolia forest were rela- tively greater compared with those of the S. przewalskii forest and shrubs. However, silt content and soil bulk density were relatively smaller than those in the S. przewalskii forest and shrubs. In addition, there was a sig- nificant linear positive relationship between averaged soil water content and soil organic matter content （P〈0.0001）. However, this relationship is not significant in the P. crassifolia forest. As depicted in the SWRCs, the water storage capacity of the soil was 39.14% and 37.38% higher in the P. crassifolia forest

关键词： vegetation soil water storage soil properties soil water retention curve forest catchment Heihe River

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Spatiotemporal patterns of precipitation based on the Bayesian maximum entropy method in a typical catchment of the Heihe River watershed,northwest China

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International Journal of Digital Earth 2022年第1期15卷 911-933页

作者： Hong Wang chuanyan zhao Fei Zang Zhanlei Rong Yapeng Chang Youyan Liu State Key Laboratory of Grassland Agro-ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouPeople’s Republic of China College of Geographical Science Qinghai Normal UniversityXiningPeople’s Republic of China Academy of Plateau Science and Sustainability People’s Government of Qinghai Province & Beijing Normal UniversityXiningPeople’s Republic of China Qinghai Research Centre of Qilian Mountain National Park Qinghai Normal UniversityXiningPeople’s Republic of China

Precipitation patterns are vital to water resource management and hydrological research,especially in the upper reaches of inland rivers in arid and semiarid ***,estimating spatiotemporal precipitation patterns at a basin scale is challenging due to limited *** this study,spatiotemporal patterns of precipitation amount,frequency,duration,and intensity at different time scales from 2014 to 2019 are estimated using the Bayesian maximum entropy method in the Tianlaochi catchment of the Heihe River watershed,northwest *** study's results show that the annual average precipitation amount was 535.9 mm from 2014 to 2019,with precipitation amount between May and September accounting for 85.9%of the annual precipitation *** daily precipitation,the average frequency rate of light precipitation is highest at 59.55%,however,the average contribution rate of moderate precipitation is highest at 50.33%.The spatial distribution of precipitation is characterized by high-value areas concentrated in the central valley and low-value areas located at the catchment's *** most important driving factors of precipitation patterns are elevation,relative humidity,and wind *** outcomes can be used to establish accurate hydrological models in the catchment and provide support for water resource management in the Heihe River watershed.

关键词： Geostatistics precipitation patterns spatial estimation cross-validation grey relational analysis

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Physiological responses of Populus euphratica Oliv. to groundwater table variations in the lower reaches of Heihe River, Northwest China

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Journal of Arid Land 2012年第3期4卷 281-291页

作者： Yang zhao chuanyan zhao ZhongLin XU YiYue LIU Yao WANG Chao WANG HuanHua PENG XiangLin ZHENG State Key Laboratory of Pastoral Agricultural Ecosystem Institute of Arid Agroecology School of Life Science Lanzhou Uni-versity Lanzhou 730000 China MOE Key Laboratory of Oasis Ecology College of Resource and Environmental Science Xinjiang University Urumqi 830002China Key Laboratory of Western China's Environment Systems MOE Lanzhou University Lanzhou 730000 China

Riparian vegetation in the lower reaches of Heihe River serves important ecological functions. However, the riparian ecosystems have been constantly deteriorating in the past 30 years simply due to water interception for oasis agricultural irrigation in the middle reaches of the river. This study pays a particular attention to Populus eu- phratica Oily. forest because it is a dominant component of the riparian ecosystem in the lower reaches of Heihe River where the depth of groundwater table is the controlling factor in sustaining riparian ecosystems. To reveal leaf-related physiological responses of Populus euphratica Oliv. forest to groundwater table variations, we analyzed the relationships between the depth of groundwater table （DG） and three leaf-related parameters, i.e. leaf stomatal density （SD）, specific leaf area （SLA）, and stable carbon isotopic composition （6~SC）. Our results show that the relationship between DG and leaf SD is a bi-mode one shaped by both salt stress and water stress. That is, salt stress appeared in shallow groundwater conditions and water stress happened in deep groundwater conditions, and the thin layer around 2.7 m of DG is a stress-free layer. Leaf SD fluctuated according to the DG variation, first de- creased with increasing DG, then increased at depths ranging 2.7-3.7 m, and after a relatively stable plateau of SD at depths ranging 3.7-5.2 m, decreased again with increasing DG. Our results also show that SLA decreased ex- ponentially with increasing DG and foliar 6130 values are also strongly dependent on DG, further demonstrating that these two parameters are sensitive indicators of water stress. The exponential curve suggests that SLA is more sensitive to DG when groundwater table is shallow and 3 m seems to be a threshold beyond which SLA becomes less sensitive to DG. Foliar 613C becomes more sensitive when the groundwater table is deep and 7 m seems to be a threshold below which the 6130 signature becomes more sensitive to DG.

关键词： opulus euphratica Oily stable carbon isotopic composition stomatal density specific leaf area groundwater table

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Leaf gas exchange and photosynthesis curves of Elymus nutans and Potentilla anserina under fencing and grazing conditions in the Qilian Mountains, Northwest China

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Journal of Arid Land 2019年第3期11卷 431-445页

作者： LIU Junjie WANG Xiaoping GAO Yunfei RONG Zhanlei ZHANG Guangde WANG Wenbin GE Lijuan MAO Yahua GUO zhaoxia zhao chuanyan State Key Laboratory of Grassland Agro-ecosystems School of Life SciencesLanzhou UniversityLanzhou 730000China Institute of Arid Meteorology China Meteorological AdministrationLanzhou 730020China

Potentilla anserina *** Elymus nutans *** dominant species in the subalpine meadows of *** is one of the most important factors that influence community structure and productivity of subalpine *** how grazing changes photosynthetic capability is essential for preservation and restoration of ***,information about the effects of grazing on photosynthetic capability remains *** were conducted in fencing and grazing areas in the Qilian Mountains,Northwest *** leaf gas exchange and photosynthetic curves of *** and *** were measured at different growth *** showed that grazing decreased the values of leaf gas exchange parameters,such as net photosynthetic rate,stomatal conductance,transpiration rate,and intercellular CO2 concentration of *** and *** addition,grazing decreased the values of net photosynthetic rate-photosynthetically active radiation(PN-PAR)curve parameters,such as light-saturated net photosynthetic rate,apparent quantum efficiency,light compensation point,light saturation point,and dark respiration *** results demonstrated that grazing was the primary limiting factor for photosynthesis of dominant grassland species in the study area.

关键词： grazing diurnal variation gas exchange Potentilla anserina Elymus nutans photosynthetic capacity

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Actual evapotranspiration of subalpine meadows in the Qilian Mountains, Northwest China

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Journal of Arid Land 2019年第3期11卷 371-384页

作者： GAO Yunfei zhao chuanyan Muhammad W ASHIQ WANG Qingtao RONG Zhanlei LIU Junjie MAO Yahua GUO zhaoxia WANG Wenbin State Key Laboratory of Grassland and Agro-Ecosystems School of Life SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Grassland and Agro-Ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China Ministry of Natural Resources and Forestry Timmins District5520 Hwy 101 ESouth PorcupineONPON 1 HOCanada

As a main component in water balance,evapotranspiration(ET)is of great importance for water saving,especially in arid and semi-arid *** this study,the FAO(Food and Agriculture Organization)Penman-Monteith model was used to estimate the magnitude and temporal dynamics of reference evapotranspiration(ET0)in 2014 in subalpine meadows of the Qilian Mountains,Northwest ***,actual ET(ETc)was also investigated by the eddy covariance(EC)*** indicated that ETc estimated by the EC System was 583 mm,lower than ET0(923 mm)estimated by the FAO Penman-Monteith model in ***,ET0 began to increase in March and reached the peak value in August and then declined in September,however,ETc began to increase from April and reached the peak value in July,and then declined in *** ETc and ET0 values during the growing season(from May to September)were 441 and 666 mm,respectively,which accounted for 75.73%of annual cumulative ETc and 72.34%of annual cumulative ET0,respectively.A crop coefficient(kc)was also estimated for calculating the ETc,and average value of kc during the growing season was 0.81(ranging from 0.45 to 1.16).Air temperature(Ta),wind speed(u),net radiation(Rn)and soil temperature(Ts)at the depth of 5 cm and aboveground biomass were critical factors for affecting kc,furthermore,a daily empirical kc equation including these main driving factors was *** result demonstrated that the ETc value estimated by the data of kc and ET0 was validated and consistent with the growing season data in 2015 and 2016.

关键词： actual evapotranspiration reference evapotranspiration crop coefficient meteorological factors biotic factors

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Modified non-rectangular hyperbola equation with plant height for photosynthetic light-response curves of Potentilla anserina and Elymus nutans at various growth phases in the Heihe River Basin, Northwest China

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Journal of Arid Land 2019年第5期11卷 764-773页

作者： LIU Junjie WANG Xiaoping RONG Zhanlei GAO Yunfei ZHANG Guangde WANGWenbin GE Lijuan MAO Yahua GUO zhaoxia WANG Qingtao zhao chuanyan State Key Laboratory of Grassland Agro-ecosystems School of Life SciencesLanzhou UniversityLanzhou 730000China Institute of Arid Meteorology China Meteorological AdministrationLanzhou 730020China College of landscape and Ecological Engineering Hebei University of EngineeringHandan 056000China

The non-rectangular hyperbola(NRH)equation is the most popular method that plots the photosynthetic light-response(PLR)curve and helps to identify plant photosynthetic ***,the PLR curve can't be plotted well by the NRH equation at different plant growth phases due to the variations of plant ***,plant physiological parameters have been considered into the NRH equation to establish the modified NRH equation,but plant height(H),an important parameter in plant growth phases,is not taken into *** this study,H was incorporated into the NRH equation to establish the modified NRH equation,which could be used to estimate photosynthetic capability of herbage at different growth *** explore photosynthetic capability of herbage,we selected the dominant herbage species Potentilla anserina *** Elymus nutans *** the Heihe River Basin,Northwest China as the research ***,twenty-four PLR curves and H at different growth phases were measured during the growing season in *** showed that the maximum net photosynthetic rate and the initial slope of PLR curve linearly increased with *** modified NRH equation,which is established by introducing H and an H-based adjustment factor into the NRH equation,described better the PLR curves of *** and *** than the original *** results may provide an effective method to estimate the net primary productivity of grasslands in the study area.

关键词： plant height modified non-rectangular hyperbola equation Potentilla anserina Elymus nutans photosynthetic light-response curve Qilian Mountains

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极端干旱区尾闾湖生态需水估算——以东居延海为例

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生态学报 2014年第8期34卷 2102-2108页

作者：张华张兰赵传燕西北师范大学地理与环境科学学院兰州730070

以东居延海为研究对象,利用遥感技术目视解译ETM影像,提取东居延海2002—2012年各月湖面面积。通过水文保证率法确定不同保证率下的湖面面积,结合额济纳旗气象站观测的风速、相对湿度、气温、水汽压、降水量等气象数据估算湖泊蒸发耗水... 详细信息

以东居延海为研究对象,利用遥感技术目视解译ETM影像,提取东居延海2002—2012年各月湖面面积。通过水文保证率法确定不同保证率下的湖面面积,结合额济纳旗气象站观测的风速、相对湿度、气温、水汽压、降水量等气象数据估算湖泊蒸发耗水量和湖泊降水补给量,根据湖泊渗漏系数估算湖泊渗漏量,最后运用水平衡原理构建湖泊生态需水模型,估算了东居延海在湖面面积保证率为50%、75%、95%时各月月均和年均生态需水量,其中年均生态需水量分别为1.78×108、1.60×108、1.03×108m3,约占莺落峡年均径流量的9.66%、8.66%、5.59%,约占正义峡年均径流量的16.27%、14.60%、9.42%,约占狼心山年均径流量的30.81%、27.65%、17.84%。

关键词：东居延海生态需水湖面蒸发渗漏量 ETM影像

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基于野外台站的“自然地理学”实践教学探索与实践:以兰州大学草业科学专业为例

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草业科学 2024年第7期41卷 1775-1780页

作者：李伟斌赵传燕草种创新与草地农业生态系统全国重点实验室/兰州大学农业农村部草牧业创新重点实验室/兰州大学草地农业教育部工程研究中心/草业科学国家级实验教学示范中心/兰州大学草地农业科技学院甘肃兰州730020 祁连山中部亚高山生态系统野外科学观测研究站甘肃张掖734000

利用野外台站建设的优势开展“自然地理学”实践教学,培养学生的实践能力和科技创新能力、提升教学效果,是当前“自然地理学”实践教学探索的重点方向。本文以兰州大学草业科学专业为例,从野外台站的选择、实践内容的设计与优化、新教... 详细信息

利用野外台站建设的优势开展“自然地理学”实践教学,培养学生的实践能力和科技创新能力、提升教学效果,是当前“自然地理学”实践教学探索的重点方向。本文以兰州大学草业科学专业为例,从野外台站的选择、实践内容的设计与优化、新教学模式的探索等方面,系统论述了基于野外台站的实践教学在“自然地理学”教学中的应用,总结分析了实践教学在“自然地理学”教学中的成效,并提出了改进方向,为今后“自然地理学”课程实践教学的应用和改进提供了参考。

关键词：野外台站自然地理学实践教学教学模式

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