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Erosion response to anthropogenic activity and climatic changes during the Holocene: case studies in northwestern China and southern Norway

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Journal of Geographical Sciences 2002年第4期12卷 467-471页

作者： HE Xiubin1,2, TANG Keli1, John A Matthews3, Geraint Owen3(1. inst.tute of soil and water conservation, CAS, Yangling 712100, China 2. Northwest SCI-Tech University of Agriculture and Forestry, Yangling 712100, China 3. Department of Geography, Univer inst.tute of soil and water conservation CAS Yangling China Northwest SCI-Tech University of Agriculture and Forestry Yangling China Department of Geography University of Wales Swansea UK

soil erosion assessment and prediction play critical roles in addressing problems associated with erosion control or soil conservation. The past dynamics of soil erosion can provide valuable information for us to understand the relations of soil erosion to environmental change and anthropogenic activity. The present paper has compared Holocene climatic changes in northwestern China with those in southern Norway, and investigated the past dynamics of erosion activity during the Holocene. Modern soil erosion on the Loess Plateau is a combination of the intensive natural erosion and human-induced erosion, the latter being four times greater than the former. Because of global warming and increasing human activities, climate on the Loess Plateau is becoming dryer and more unstable, causing an enhanced erosion problem and water scarcity. In the arctic-alpine region of southern Norway, however, the global warming and regional wetting caused expansion of the largest European ice cap. This has accentuated the erosion in that region, with a higher frequency of avalanches and debris flows.

关键词： anthropogenic activity China climate changes erosion response Norway

Implications of agricultural success in the Yellow River Basin and its strategy for green development

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 122-133页

作者： Gang HE Zhaohui WANG Qichao ZHU Jianbo SHEN Fusuo ZHANG College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Low-carbon Green Agriculture in northwestern China Ministry of Agriculture and Rural AffairsBeijing 100125China College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China

The Yellow River Basin is an important food production area and an ecological challenge for China, where environmental protection and water scarcity are the major constraints. For the upper reaches of the Yellow River Basin,optimizing the adoption of chemicals in agricultural production and integrating crops with livestock are the key strategies for protecting the *** dryland agriculture in the middle and upper reaches, this study summarizes four aspects of efficient precipitation techniques in terms of collection,storage, conservation, and use, which have greatly improved crop yields and supported dryland crop production. Irrigated agriculture in the middle and lower reaches is the core area of China's grain production, where the area under water-saving irrigation reached 13.0 Mha in 2018, greatly improving water use. Compared with 1998, cereal production in 2018 increased by 62.2 Mt under similar total water withdrawals(49.7 billion to 51.6 billion m~3),and the annual soil erosion at the Tongguan Hydrological Observatory reduced by 584 million m~3 in 2018, achieving great success in environmental protection and efficient water use. The Chinese government has set a goal for the Yellow River Basin to become the national leader in environmental protection and efficient water use by 2035. Such a high demand requires the combined efforts of the whole community, as well as the adoption of new technologies,coordinated basin-wide development, and adequate policy support.

关键词： Ecological agriculture drylands agriculture irrigation water-saving technology policy support

Selenium Accumulation and Antioxidant Status of Rice Plants Grown on Seleniferous soil from northwestern India

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Rice science 2014年第6期21卷 327-334页

作者： Sucheta SHARMA Reeti GOYAL Upkar Singh SADANA Department of Biochemistry Punjab Agricultural University Department of soil Science Punjab Agricultural University

Greenhouse experiment was conducted to investigate selenium accumulation and its antioxidant response in two rice varieties （PR116 and Pusa Basmati 1121） grown on normal and seleniferous soils. The plant growth was reduced at early developmental stages and flowering was delayed by a period of 10 d on seleniferous soil. Selenium accumulation increased by 3-20 and 13-14 folds in leaves, 18 and 3 folds in grains from Pusa Basmati 1121 and PRl16 varieties, respectively. Selenium accumulation in leaves from rice plants grown on seleniferous soil resulted in significant increase in chlorophyll content, hydrogen peroxide, proline, free amino acids, total phenol and tannin contents. Lipid peroxidation levels and peroxidase activities in leaves increased whereas catalase activity showed a reverse trend. It is concluded that selenium accumulation decreased dry matter content in rice during crop development but these plants were able to combat selenium toxicity by inducing alterations in their defense system.

关键词： antioxidant enzyme chlorophyll content rice selenium

soil EROSION PROCESS RESEARCH AND ITS POTENTIAL IMPACT ON EROSION PREDICTION MODEL DEVELOPMENT

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International Journal of Sediment Research 2005年第4期20卷 350-357页

作者： Chi-hua HUANG1 and Fenli ZHENG2soil Erosion Research Laboratory, Purdue Univ., West Lafayette, IN 47907-2077, USA. State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau, inst.tute of soil and water conservation, CAS and MOWR, northwestern A & Univ. soil Erosion Research Laboratory Purdue Univ. West Lafayette IN 47907-2077 USA State Key Laboratory of soil Erosion and Dryland Fanning on the Loess Plateau Institute of Soil and Water Conservation CAS and MOWR Northwestern A & Univ. Yangling Shaanxi 712100 China

This paper highlights past efforts in developing erosion process concepts that lead to the development of the current process-based erosion prediction model, i.e., WEPP. Recent progress includes the development of a multiple-box system that can simulate hillslope hydrologic conditions. Laboratory procedures enable the quantification of near-surface hydrologic effects, i.e., artesian seepage vs. drainage, on the soil erosion process and sediment regime, flow hydraulics, and sediment transport and deposition processes. These recent findings improve soil erosion science and provide new erosion control strategies that may have additional environmental benefits relative to the traditional erosion control practices. The paper also discusses the potential impacts of the erosion process on erosion model development and future research directions of soil erosion process research and model development .

关键词： soil erosion process Erosion prediction model Surface condition Spatial and temporal variability Transport capacity

Effects of mulching for water conservation on soil carbon,nitrogen and biological properties

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Frontiers of Agricultural Science and Engineering 2017年第2期4卷 146-154页

作者： Xiaomin PI Tongxun ZHANG Benhua SUN Quanhong CUI Yun GUO Mingxia GAO Hao FENG David W.HOPKINS Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China of Ministry of Agriculture/College of Natural Resources and Environment Northwest A&F University inst.tute of water Saving Agriculture in Arid Areas of China Northwest A&F University College of water Resources and Architectural Engineering Northwest A&F University inst.tute of water and soil conservation Chinese Academy of Sciences and Ministry of Water Resources The Royal Agricultural University

The effect of mulching with straw, white plastic film and black plastic film for improving soil water storage and on the soil properties was examined in a wheat-maize rotation system on Loess soil in northwestern China. All the mulches improved the water storage to some extent and led to warmer soils. However, the organic C and total N contents of the soils declined significantly under the mulches, particularly the plastic film mulches,and this could have long-term detrimental effects on soil quality and the sustainability of the some mulching practices.

关键词： biomass carbon mulch nitrogen plastic films soil straw water storage

Lanthanum chloride improves maize grain yield by promoting photosynthetic characteristics, antioxidants enzymes and endogenous hormone at reproductive stages

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Journal of Rare Earths 2019年第7期37卷 781-790页

作者： Wenwen Cui Muhammad Kamran Quanhao Song Bingyun Zuo Zhikuan Jia Qingfang Han Key Laboratory of Crop Physiological Ecology and Tillage in northwestern Loess Plateau of Ministry of Agriculture/College of Agronomy Northwest A&F University Yangling 712100China Key Laboratory of Agricultural soil and water Engineering in Arid and Semiarid Areas Institute of Water-saving Agriculture in Arid of ChinaNorthwest A&F UniversityYangling 712100China Zhumadian Academy of Industry Innovation and Development Huanghuai UniversityZhumadian 463000China Zhumadian Academy of Agricultural Sciences Zhumadian 463000China

Despite an increase in application spectrum of rare earth elements in agriculture, all studies show that the suitable accumulation of rare earth elements can improve the crop seedling growth, but there is little research about REEs on physiological mechanisms of crops at reproductive stages. Therefore, this study was conducted to examine the possible potential benefits of lanthanum chloride(LaCl3) on the senescence and grain yield responses of maize. In this study, maize seeds were pre-treated by soaking with LaCl3 at the concentrations of 0(CK), 400(LC1), 800(LC2) and 1200(LC3) μmol/L, to evaluate its effect on the green leaf area, chlorophyll contents, photosynthesis, antioxidants, endogenous hormones in the later crop growth stages. The results show that LC1 and LC2 treatments evidently increase green leaf area, above ground dry biomass, accompanied by a distinct increase in the chlorophyll contents, and photo synthetic capacity, which promote the ear characteristics and grain yield of maize. In addition, LC1 and LC2 treatments simultaneously increase the activities of antioxidants, including superoxide dismutases, catalases, peroxidases, soluble protein, and enhanced levels of auxin, gibberellin and zeatin,following a dose-response tendency. Themalondialdehyde and abscisic acid levels transiently increase with the progression in the growth stage of the crop but are markedly decreased at LC1 and LC2 treatments, while LC3 treatment has no significant effect on malondialdehyde and even accelerates the accumulation of abscisic acid in maize leaves. Our data suggest that seed priming with LaCl3 at a suitable concentration range(400-800 μmol/L) can prolong the functional periods of leaves, increase photosynthetic capacity, enhance antioxidant activity, and alter endogenous hormone levels at reproductive stages, resulting in delaying leaf senescence rate and increasing yield. However, the moderate concentration of LaCl3 for maize is LC2(800 μmol/L), and can be effectiv

关键词： Seed priming LaCl3 Maize Photosynthesis Antioxidants Endogenous hormones

Research progress on control of Orobanche by trap crops

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Research progress on control of Orobanche by trap crops

Utilizing comprehensive decision analysis methods to determine an optimal planting pattern and nitrogen application for winter oilseed rape

中国第六届植物化感作用学术研讨会

作者： MA Yong-qing The State Key Laboratory of soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University

Broomrapes (members of the genus Orobanche) are biennial or perennial parasitic plants belonging to the family Orobanchaceae,which are national key entry quarantine *** to now,over 100 species of the genus Orobanche were identified worldwide which are distributed almost *** China,23 species were identified which are mainly distributed in northwestern ***,***,***,*** and *** are the most damageable among these *** *** parasitic plants which could parasitized the roots of their *** could produce a large number of tiny *** the seeds are spread widely,it is difficult to fully wipe *** seeds with strong viability can overwinter in the soil and stay viable for 5 to 10 years in absent of the ***,Orobanche is not only a harmful parasitic weed but also a stubborn weed with a long-term *** other plants,parasitic weeds of the genus Orobanche could produce a large number of seeds throughout a growth *** the seeds were ripe,they enter into a period of *** the seeds completed the after-ripening process,in order to germinate,they must undergo a period of conditioning in a warm and moist environment and expose to germination *** germination,induced by historian inducers,the germ tubes of the seeds could produce haustoria which establish connections with the host roots so that the parasitic plants can parasite on the roots of the *** this way,the germ tubes can insert the host roots and absorb water and nutrients from the hosts through the vascular ***,the Orobanche could grow continually and complete its growth *** to the fact that the tiny seed of Orobanche could store limited nutrients,the germinated seeds stimulated by germination stimulants would die from nutrients depletion without finding the host roots several days after *** process is called suicidal *** common control methods are

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Journal of Integrative Agriculture 2020年第9期19卷 2229-2238页

作者： DU Ya-dan CUI Bing-jing ZHANG Qian SUN Jun WANG Zhen NIU Wen-quan Key Laboratory of Agricultural soil and water Engineering in Arid and Semiarid Area of Ministry of Education/Northwest A&F University Yangling 712100P.R.China

Oilseed rape is one of the most important oil crops *** the appropriate cultivation method(planting pattern and nitrogen level)is necessary to achieve high yield,quality and resource utilization ***,the optimal method for oilseed rape varies across countries and *** objective of the present study was to determine an appropriate cultivation method,including planting pattern and nitrogen application,for winter oilseed rape in northwestern *** planting patterns:ridge film mulching and furrow planting(RFMF)and flat planting(FP),and six nitrogen(N)amounts:0(N0),60(N60),120(N120),180(N180),240(N240),and 300(N300)kg N ha–1 were applied across three growing seasons(2014–2017).Three comprehensive decision analysis methods:principal component analysis,grey correlation degree analysis and the combined entropy weight and dynamic technique for order preference by similarity to ideal solution method were used to evaluate the growth and physiological indicators,nutrient uptake,yield,quality,evapotranspiration,and water use efficiency of winter oilseed *** pattern,nitrogen amount and their interaction significantly affected the indicators *** RFMF pattern significantly increased all indicators over the FP *** of N also markedly increased all the indicators except for seed oil content,but the yield,oil production and water use efficiency were decreased when N fertilizer exceeded 180 kg N ha–1 under FP and 240 kg N ha–1 under *** evaluation results of the three comprehensive decision analysis methods indicated that RFMF planting pattern with 240 kg N ha–1 is an appropriate cultivation method for winter oilseed rape in northwestern *** findings are of vital significance to maximize yield,optimize quality and improve resource use efficiencies of winter oilseed rape.

关键词： appropriate cultivation method comprehensive decision analysis method northwestern China winter oilseed rape

Response of yield,quality,water and nitrogen use efficiency of tomato to different levels of water and nitrogen under drip irrigation in northwestern China

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Journal of Integrative Agriculture 2017年第5期16卷 1153-1161页

作者： DU Ya-dan CAO Hong-xia LIU Shi-quan GU Xiao-bo CAO Yu-xin Key Laboratory of Agricultural soil and water Engineering in Arid and Semiarid Area Ministry of Education/Northwest A&F UniversityYangling 712100P.R.China

The objective of this study was to investigate the effects of applying different amounts of water and nitrogen on yield, fruit quality, water use efficiency （WUE）, irrigation water use efficiency （IWUE） and nitrogen use efficiency （NUE） of drip-irrigated greenhouse tomatoes in northwestern China. The plants were irrigated every seven days at various proportions of 20-cm pan evaporation （Ep）. The experiment consisted of three irrigation levels （11, 50% Ep; 12, 75% Ep; and 13, 100% Ep） and three N application levels （N1, 150 kg N ha^-1; N2, 250 kg N ha^-1;and N3, 350 kg N ha^-1）. Tomato yield increased with the amount of applied irrigation water in 12 and then decreased in 13. WUE and IWUE were the highest in Ii. WUE was 16.5% lower in 12 than that in I1, but yield was 26.6% higher in 12 than that in I1. Tomato yield, WUE, and IWUE were significantly higher in N2 than that in N1 and N3. NUIE decreased with increasing N levels but NUE increased with increase the amount of water applied. Increasing both water and N levels increased the foliar net photosynthetic rate. I1 and 12 treatments significantly increased the contents of total soluble solids （TSS）, vitamin C （VC）, lycopene, soluble sugars （SS）, and organic acids （OA） and the sugar：acid ratio in the fruit and decreased the nitrate content. TSS, VC, lycopene, and SS contents were the highest in N2. The harvest index （HI） was the highest in 12N2. 12N2 provided the optimal combination of tomato yield, fruit quality, and WUE. The irrigation and fertilisation regime of 75% Ep and 250 kg N ha^-1 was the best strategy of water and N management for the production of drip-irrigated greenhouse tomato.

关键词： tomato drip irrigation yield fruit quality water use efficiency (WUE)