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Estimating soil moisture content using laboratory spectral data

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Journal of forestry Research 2019年第3期30卷 1073-1080页

作者： Xiguang Yang Ying Yu Mingze Li Key Laboratory of Saline-Alkali vegetation ecology Restoration (SAVER) Ministry of Education Alkali Soil Natural Environmental Science Center (ASNESC) Northeast Forestry University

Monitoring soil moisture is important for agriculture and forestry and plays an essential role in land surface processes as well as providing feedback among the earth’s surface ecosystems. Large-scale regional soil moisture spatial data can be obtained with a reliable and operational approach using remote sensing. In this paper, we provide an operational framework for retrieving soil moisture using laboratory spectral data. The inverted Gaussian function was used to fit soil spectral data, and its feature parameters, including absorption depth (AD) and absorption area (AA), were selected as variables for a soil moisture estimate model. There was a significant correlative relationship between soil moisture and AD, as well as AA near 1400 and 1900 nm. A one-variable linear regression model was established to estimate soil moisture. The model was evaluated using the determination coefficients (R2), root mean square error and average *** models were established and evaluated in this study. The determination coefficients of the four models ranged from 0.794 to 0.845. The average accuracy for soil moisture estimates ranged from 90 to 92%. The results prove that it is feasible to estimate soil moisture using remote sensing technology.

关键词： Absorption feature Hyperspectral Inverted Gaussian function Remote sensing

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

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Journal of Environmental Sciences 2007年第2期19卷 217-221页

作者： XU Qiu-jin NIAN Yue-gang JIN Xiang-can YAN Chang-zhou LIU Jin Jiang Gao-ming Lake Research Center Chinese Research Academy of Environmental Sciences Beijing 100012 China Quantitative vegetation ecology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Effects of chitosan on a submersed plant, HydriUa verticillata, were investigated. Results indicated that H. verticillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand （COD）. Superoxide dismutase （SOD） activity and malondialdehyde （MDA） contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD （980 rag/L） and decreased with low COD （63 mg/L）, respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant ceils from the control experiment （untreated with chitosan） were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.

关键词： antioxdiant enaymes chitosan Hydrilla verticiUata malondialdehyde superoxide dismutase ultrastructure

Stress response of Lymantria dispar asiatica(Lepidoptera:Erebidae)larvae and its gut microbiota to manganese ion

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Journal of forestry Research 2021年第3期32卷 1241-1251页

作者： Jianyong Zeng Jiaxing Guo Jianghong Shi Zhongbin Shi Guocai Zhang Jie Zhang Department of forest Protection College of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Saline-alkali vegetation ecology Restoration Ministry of EducationCollege of Life ScienceNortheast Forestry UniversityHarbin 150040People’s Republic of China

To study the effect of manganese exposure on the herbivorous insect Lymantria dispar asiatica,fourthinstar larvae were fed a MnCl_(2)-amended diet(LdMn)for 84 h(0.40 mmol MnCl_(2)/g diet).Larvae were weighed before and after the diet administration to assess larval gain in mass under manganese *** whole bodies of half of the survivors were ground in liquid nitrogen for measuring enzyme activities and total antioxidant capacity(T-AOC).The intestinal tracts of the remaining survivors were collected and immediately frozen in liquid nitrogen for 16S rDNA sequencing of gut *** under manganese stress lost significant mass(p<0.05).The activities of digestive and antioxidant enzymes and T-AOC,but not trehalase and polyphenol oxidase,were significantly higher after Mn exposure,(p<0.05).A Venn diagram illustrated that the gut microbial OTU composition in the larvae also *** pies and correlation heatmaps also showed different relative abundances of gut *** other words,species quantity and relative abundance of gut microbes agreed with PCoA visualization and indicated that the gut microbial community in *** asiatica larvae differed significantly between control and *** classification also suggested that exposure to manganese stress significantly decreased gut microbial coenzyme transport and metabolism in *** asiatica *** results further our understanding about stress response of *** asiatica larvae.

关键词： Insect Manganese stress Enzyme Antioxidation Gut microbiota

A preliminary study of water use strategy of desert plants in Dunhuang,China

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Journal of Arid Land 2015年第1期7卷 73-81页

作者： YongQin CUI JianYing MA Wei SUN JiaHuan SUN ZhengHu DUAN Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Xinjiang Institute of ecology and Geography Chinese Academy of Sciences Ministry of Education Key Laboratory of vegetation ecology Institute of Grassland Science Northeast Normal University

Water is a restrictive factor for plant growth and ecosystem stability in arid and semiarid areas. The dynamics of water availability in soils and water use by plants are consequently critical to ecosystem functions, e.g. maintaining a high resistance to the changing climate. Plant water use strategies, including water-use efficiency （WUE） and the main water source that a plant species utilizes, play an important role in the evaluation of stability and sustainability of a plantation. The water use strategies of desert plants （Tamarix chinensis, Alhagi sparsifolia, Elaeagnus angustifolia, Sophora alopecuroides, Bassia dasyphylla and Nitraria sphaerocarpa） in three different habitats （saline land, sandy land and Gobi） in Dunhuang （located in the typical arid area of northwestern China） were studied. The stable isotope of oxygen was used to determine the main water source and leaf carbon isotope discrimination was used to estimate the long-term WUE of plant species in the summer of 2010. The results suggest that： 1） the studied desert plants took up soil water below the depth of 80 cm; 2） T. chinensis in the three habitats used deeper soil water and T. chinensis in the Gobi site had higher WUE than those in the saline land and the sandy land. The results indicated that desert plants in Dunhuang depended on stable water source and maintained high WUE to survive in water limited environments.

关键词： desert plant stable isotope water source water-use efficiency Dunhuang

Temporal variability of global potential water erosion based on an improved USLE model

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International Soil and Water Conservation Research 2024年第1期12卷 1-12页

作者： Jialei Li Muqi Xiong Ranhao Sun Liding Chen State Key Laboratory of Urban and Regional ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China

Assessing spatiotemporal variation in global soil erosion is essential for identifying areas that require greater attention and management under the effects of anthropogenic activities and climate *** erosion can be modelled using the universal soil loss equation(USLE),which includes rainfall erosivity(R-factor),vegetation cover(C-factor),topography(LS-factor),soil erodibility(K-factor),and management practices(P-factor).However,global soil erosion modeling faces numerous challenges,including data acquisition,calculation processes,and parameter calibration under different climatic and topographic ***,we presented an improved USLE-based model using highly distributed *** R-,C-,and P-factors were modified by the climate zone,country,and *** distributed model was applied to estimate the intensity and variations in global soil erosion from 1992 to *** validated the accuracy of this model by comparing simulations with measurements from 11,439 plot years of erosion *** results showed that i)the average global erosion rate was 5.78 t ha^(-1)year^(-1),with an increase rate of 4.26×10^(-3)t ha^(-1)year^(-1);ii)areas with significantly increasing erosion accounted for 16%of the land with water erosion,whereas those with significantly decreasing erosion accounted for 7%;and iii)areas with severe erosion included the western Ghats,Abyssinian Plateau,Brazilian Plateau,south and east of the Himalayas,and western coast of South *** erosion occurred mainly on the Amazon Plain and the northern coast of the *** study provides an improved water erosion prediction model and accurate information for researchers and policymakers to identify the drivers underlying changes in water erosion in different regions.

关键词： Soil erosion Distributed USLE model Rainfall erosivity Soil conservation Global change

A GIS-based Modeling Approach for Fast Assessment of Soil Erosion by Water at Regional Scale, Loess Plateau of China

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Chinese Geographical Science 2010年第5期20卷 423-433页

作者： HU Llangjun YANG Haijun YANG Qinke LI Rui Key Laboratory for vegetation ecology of Ministry of Education Northeast Normal University Changchun 130024 China Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China

The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of both regional patterns of soil loss and its impact factors in the plateau area. Based on the regional characteristics of precipitation, vegetation and land form, and with the use of Landsat TM and ground investigation data, the entire Loess Plateau was first divided into 3 380 Fundamental Assessment Units （FAUs） to adapt to this regional modeling and fast assessment. A set of easily available parameters reflecting relevant water erosion factors at a regional scale was then developed, in which dynamic and static factors were discriminated. Arclnfo GIS was used to integrate all essential data into a central database. A resulting mathematical model was established to link the sediment yields and the selected variables on the basis of FAUs through overlay in GIS and multiple regression analyses. The sensitivity analyses and validation results show that this approach works effectively in assessing large area soil erosion, and also helps to understand the regional associations of erosion and its impact factors, and thus might significantly contribute to planning and policymaking for a large area erosion control in the Loess Plateau.

关键词： soil erosion by water G/S-based modeling soil erosion assessment regional scale Loess Plateau

Spatial distributions of soil nutrients affected by land use,topography and their interactions,in the Loess Plateau of China

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International Soil and Water Conservation Research 2024年第1期12卷 227-239页

作者： Wenxin Zhou Changjia Li Wenwu Zhao Lindsay C.Stringer Bojie Fu State Key Laboratory of Earth Surface Processes and Resource ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Department of Environment and Geography University of YorkYorkUK York Environmental Sustainability Institute University of YorkYorkUK

Soil nutrient availability and their spatial distributions are strongly related to land use and landscape *** study aims to address the knowledge gap regarding the interaction between these factors and the underlying *** selected five land uses(grassland with Artemisia gmelinii,woodland with Robinia pseudoacacia,shrubland with Caragana korshinskii and Hippophae rhamnoides,and apple orchard with Malus pumila)and nine slope positions across hillslopes in the Loess Plateau,China,to investigate their combined effects on the contents and stocks of soil organic carbon(SOC),total nitrogen(TN)and total phosphorus(TP).Parametric and non-parametric statistical tests were conducted to determine the significant differences in the means or the medians of the soil nutrient *** showed that the SOC and TN contents of shrubland with Caragana korshinskii were statistically significantly greater than those of the grassland(pvegetation type and slope positions in land management and vegetation restoration activities.

关键词： Soil organic carbon Total nitrogen Total phosphorus Slope position vegetation restoration

Responses of Caryopsis Germination, Seedling Emergence, and Development to Sand Water Content of Agropyron cristatum （L.） Gaertn. and Bromus inermis Leyss.

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Journal of Integrative Plant Biology 2005年第12期47卷 1450-1458页

作者： Hui-Ling YANG Xuan-Wei ZHU Ming DONG Zhen-Ying HUANG Zhi-Ping CAO College of Resources and Environmental Sciences China Agricultural University Beijing 100094 China Laboratory of Quantitative vegetation ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Responses of caryopsis germination, seedling emergence, and development of Agropyron cristatum （L.） Gaertn. （Gramineae） and Bromus inermis Leyss. （Gramineae）, two dominant perennial grasses in the Otindag Sandland of China, to different sand water content （SWC; 1%, 2%, 3%, 4%, 6%, 8%, 12%, 16%, and 20%） were studied comparatively. The results showed that the germination responses of the two grasses to SWC were similar （i.e. caryopses could not germinate when the SWC was below 3%; at SWC ranging from 3% to 12%, the higher the SWC, the higher the germination percentage; and at a SWC of 12%-20%, germination reached similarly high percentages）. At a sand burial depth of 0.5 cm, the threshold of SWC for seedling emergence was 6% forA. cristatum and 8% forB. inermis; at 12%-20% SWC, the seedling emergence of both species reached similarly high percentages. The seedling growth responses of these two species to SWC gradients were different. For A. cristatum, the biomass of seedlings increased with SWC from 6% to 12%, and decreased with SWC from 12% to 20%. For B. inermis, the biomass of seedlings always increased with SWC from 8% to 20%. The results also showed that the seedlings of both species allocated more biomass to the roots with decreases in SWC. The SWC changes from April to October in natural microhabitats of both species suggested that the SWC may play an important role in caryopsis germination, seedling emergence, and the growth characteristics of the two grasses. The responses of caryopsis germination, seedling emergence, and the growth characteristics of these two species to SWC may determine their distribution pattems in the Otindag Sandland.

关键词： Agropyron cristatum Bromus inermis caryopsis germination Otindag Sandland sand water content seedling emergence seedling growth characteristics.

Growth and decline of arboreal fungi that prey on Bursaphelenchus xylophilus and their predation rate

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Journal of forestry Research 2022年第2期33卷 699-709页

作者： Haixiao Zhang Zhiyan Wei Xuefeng Liu Jie Zhang Guiping Diao Heilongjiang Province Key Laboratory of forest Protection College of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Saline-Alkali vegetation ecology Restoration Ministry of EducationCollege of Life SciencesNortheast Forestry UniversityHexing Road 26Xiangfang DistrictHarbin 150040People’s Republic of China

Pine wilt disease caused by pine wood nema-todes is a deadly disease of the genus Pinus requiring strong quarantine *** its discovery,it has been widely distributed throughout the *** is one of the coun-tries with a severe rate of infections due to its abundant pine *** this study,nematode-trapping fungi were collected from pine trees in Ninghai City,Zhejiang Prov-ince,which is the key area of pine wilt control in Febru-ary,May,September,October and *** results showed that nematode-trapping fungi of pine are abundant,especially the number and species detected in each month and are quite different;species of fungi in July,Septem-ber and November were more numerous and had higher separation *** dominant species in November was Arthrobotrys oligospora followed by Arthrobotrys cladodes;July and September it was *** each part of the tree,*** was the most widely distributed with a high separation ***,it is the dominant fungal species in the *** Bursaphelenchus xylophilus-trapping fungi are dependent on pine wood nematodes,and none were isolated from healthy pine *** arboreal ***-trapping fungi were found under the bark than in the *** is a close relationship between arboreal ***-trapping fungi and pine wood *** to make use of these resources to reduce the damage of pine wood nematode fusarium is the focus of future research.

关键词： Arboreal Bursaphelenchus xylophilus-trapping fungi Distribution Dominant species Culture conditions Rate of predation