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Influences of Long-Term Fertilizer and Tillage Management on Soil Fertility of the North China Plain

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Pedosphere 2011年第6期21卷 813-820页

作者： NIU Ling-An HAO Jin-Min ZHANG Bao-Zhong NIU Xin-Sheng Quzhou experimental station China Agricultural University Quzhou 057250 （China）

In the North China Plain, fertilizer management and tillage practices have been changing rapidly during the last three decades; however, the influences of long-term fertilizer applications and tillage systems on fertility of salt-affected soils have not been well understood under a winter wheat (Triticum aestivum L.)-maize (Zea mays L.) annual double cropping system. A field experiment was established in 1985 on a Cambosol at the Quzhou experimental station, China Agricultural University, to investigate the responses of soil fertility to fertilizer and tillage practices. The experiment was established as an orthogonal design with nine treatments of different tillage methods and/or fertilizer applications. In October 2001, composite soil samples were collected from the 0–20 and 20–40 cm layers and analyzed for soil fertility indices. The results showed that after 17 years of nitrogen (N) and phosphorous (P) fertilizer and straw applications, soil organic matter (SOM) in the top layer was increased significantly from 7.00 to 9.30–13.14 g kg-1 in the 0–20 cm layer and from 4.00 to 5.48–7.75 g kg-1 in the 20–40 cm layer. Soil total N (TN) was increased significantly from 0.37 and 0.22 to 0.79–1.11 and 0.61–0.73 g N kg-1 in the 0–20 and 20–40 cm layers, respectively, with N fertilizer application; however, there was no apparent effect of straw application on TN content. The amounts of soil total P (TP) and rapidly available P (RP) were increased significantly from 0.60 to 0.67–1.31 g kg-1 in the 0–20 cm layer and from 0.52 to 0.60–0.73 g kg-1 in the 20–40 cm layer with P fertilizer application, but were decreased with combined N and P fertilizer applications. The applications of N and P fertilizers significantly increased the crop yields, but decreased the rapidly available potassium (RK) in the soil. Straw return could only meet part of the crop potassium requirements. Our results also suggested that though some soil fertility parameters were maintained or enhanced unde

关键词： rapidly available K rapidly available P soil organic matter straw return total N

Subsoiling and Ridge Tillage Alleviate the High Temperature Stress in Spring Maize in the North China Plain

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Journal of Integrative Agriculture 2013年第12期12卷 2179-2188页

作者： TAO Zhi-qiang SUI Peng CHEN Yuan-quan LI Chao NIE Zi-jin YUAN Shu-fen SHI Jiang-tao GAO Wang-sheng College of Agronomy and Biotechnology China Agricultural University Wuqiao experimental station China Agricultural University

High temperature stress（HTS） on spring maize（Zea mays L.） during the filling stage is the key factor that limits the yield increase in the North China Plain（NCP）.Subsoiling（SS） and ridge tillage（R） were introduced to enhance the ability of spring maize to resist HTS during the filling *** field experiments were conducted during the 2011 and 2012 maize growing seasons at Wuqiao County,Hebei Province,*** with rotary tillage（RT）,the net photosynthetic rate,stomatal conductance,transpiration rate,and chlorophyll relative content（SPAD） of maize leaves was increased by 40.0,42.6,12.8,and 29.7% under SS,and increased by 20.4,20.0,5.4,and 14.2% under R,***,the treatments reduce the intercellular CO 2 concentration under *** SS and R treatments increased the relative water content（RWC） by 11.9 and 6.2%,and the water use efficiency（WUE） by 24.3 and 14.3%,respectively,compared with *** SS treatment increased the root length density and soil moisture in the 0-80 cm soil profile,whereas the R treatment increased the root length density and soil moisture in the 0-40 cm soil profile compared with the RT *** with 2011,the number of days with temperatures 33°C was more 2 d and the mean day temperature was higher 0.9°C than that in 2012,whereas the plant yield decreased by 2.5,8.5 and 10.9%,the net photosynthetic rate reduced by 7.5,10.5 and 18.0%,the RWC reduced by 3.9,5.6 and 6.2%,and the WUE at leaf level reduced by 1.8,5.2 and 13.1% in the SS,R and RT treatments,*** the root length density and the soil moisture also decreased at different *** yield,photosynthetic rate,plant water status,root length density,and soil moisture under the SS and R treatments declined less than that under the RT *** results indicated that SS and R can enhance the HTS resistance of spring maize during the filling stage,and led to higher yield by directly improving soil moisture and root growth and indirectly improving

关键词： high temperature stress spring maize filling stage subsoiling ridge tillage

Ecohydrological change mechanism of a rainfed revegetation ecosystem at southeastern edge of Tengger desert,Northwest China

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Science China Earth Sciences 2004年第Z1期47卷 71-77页

作者： XIAO Honglang CHENG Guodong LI Xinrong SONG Yaoxuan WANG Xinping Shapotou Desert experimental Research station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Study is made on a 45 km-long artificial ecosystem without irrigation in Tengger desert on the basis of long-term ecological monitoring and ecohydrological *** in water allocation, utilization, cycle and balance patterns in more than 40-year evolution of the soil-plant system are analyzed. The formation of a drought horizon in shrub rhizosphere and its effect, ecohydrological function of the crust and its effect on the soil-plant system change are discussed. Driven by water self-regulation and water stress, the soil-plant system is going to develop towards the steppe desert to ensure more effective use and optimum collocation of water resource.

关键词： ecohydrology, artificial ecosystem, soil-plant evolution, water balance, drought horizon, bio-crust, Chinese desert.

CO_(2) Assimilation Rate in Production Systems for Papaya Crops

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Phyton-International Journal of experimental Botany 2021年第3期90卷 933-947页

作者： R.Ariza-Flores D.Trujillo-García M.A.Otero-Sánchez E.Canales Sosa C.H.Avendaño-Arrazate L.A.Gálvez-Marroquín P.Cadena Iñiguez Iguala experimental station National Institute of ForestAgricultural and Livestock Research(INIFAP)IgualaCP.40000México Superior Agricultural College of the State of Guerrero IgualaGuerrero.CP.40000México Rosario Izapa experimental station-INIFAP Tuxtla ChicoChiapas.CP.30870México Valles Centrales experimental station-INIFAP OaxacaOaxaca.CP.68200México Centro de Chiapas experimental station-INIFAP OcozocoautlaChiapas.CP.29140México

The aim of this study was to evaluate some physiological aspects of papaya crops in semi conventional and organic production *** following factors assessed in this experiment were:*** systems(organic and semi conventional);***(Maradol and Maradona F1),and *** crop plants(Canavalia,vegetative cover and no cover).Twelve treatments were obtained-product of factors’combination-and distributed under a threerepetition experimental design of subdivided *** factors examined in this study,that changed the CO_(2) assimilation rate,were production system and *** was determined that the greatest gas exchange in papaya crops happened at 13:40 h but achieving the highest CO_(2) assimilation was also affected by the production system and ***,they showed some effects in CO_(2) assimilation,transpiration,stomatal conductance,intercellular CO_(2),leaf temperature,chlorophyll,and *** general,the combination of factors that accentuated in this experiment were the semi conventional-Maradona-Canavalia with a crop yield of 53.5 t ha^(-1),followed by treatments organic-Maradona-no cover and semi conventional-Maradona-vegetative cover.

关键词： Respiration production system Carica papaya L.

Effects of shrub species and microhabitats on dew formation in a revegetation-stabilized desert ecosystem in Shapotou, northern China

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Journal of Arid Land 2014年第4期6卷 389-399页

作者： YanXia PAN XinPing WANG Shapotou Desert experimental Research station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Dew is an important supplement water source in arid and semi-arid areas. In order to determine the dew formation on different kinds of soils associated with various shrub species and microhabitats, we performed measurement of accumulated dew formation amount and duration in October 2009 in a revegetation-stabilized arid desert ecosystem in Shapotou area, northern China. The results indicated that the accumulated dew formation amount was four times larger at open spaces as compared to under the canopy, and it was nearly twice as much under living Artemisia ordosica plants（L.A.） as compared to under living Caragana korshinskii plants（L.C.）. The opposite characteristics were found for dew duration between different microhabitats. Dew amounts at different vertical heights around the shrub stands were in the order of 50 cm above the canopy〉the canopy edge〉under the canopy. Dew amount continued to increase after dawn, and the proportion of average accumulated dew amount after dawn accounting for the average maximum amount increased from above the canopy to under the canopy. Dew formation duration after sunrise accounted for more than 50% of the total formation duration during the day time. Contrary to the distribution characteristics of dew amount, dew duration after dawn and total dew formation duration during the day time were both highest under the canopy, followed by at the canopy edge and then at 50 cm above the canopy. The portion of dew duration after dawn accounting for the total dew duration during the day time increased from above the canopy to under the canopy. From these results, we may conclude that dew availability as a supplemental water resource for improving the microhabitats in water-limited arid ecosystems is position dependent especially for the plant microhabitats at different stands layers.

关键词： dew amount dew duration shrub species microhabitat soil surface type

Ion Accumulation, Water Relations and Osmotic Adjustment in Atriplex argentina, A. crenatifolia, *** and A. nummularia under Saline Conditions

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Journal of Agricultural Science and Technology(A) 2016年第5期6卷 324-334页

作者： Nadia Barcena Monica Ruiz Carlos Parera Agricultural experimental station-San Juan National Institute of Agricultural Technology (INTA) Integrated Unit INTA-NationalUniversity of San Juan San Juan 5400 Argentina

Salinity is a major stress that adversely affects growth and productivity in plants. There are species that tolerate this stresswithin the genus Atriplex. Four species, A. lampa, A. crenatifolia, A. nummularia and A. argentina were compared for their ionaccumulation and water relations under saline conditions. A greenhouse study was conducted by irrigating the four species with NaCIsolutions at concentrations 0%, 1%, 2% and 4% starting when plants were six months old. Plants were harvested 45 d after startingthe salinity treatments and analyzed for their ion contents. In the four Atriplex species, Na^＋ and Cl^- contents in plants increased, whileCa^2＋ and Mg^2＋ decreased with the increase of salinity in the irrigation solution. The results suggested that A. argentina and *** were able to maintain a higher leaf relative water content （RWC） at low leaf water potential, which was associated witha greater capacity of osmotic adjustment. A. lampa showed lower ion accumulation and minor osmotic adjustment than the otherspecies. It can be concluded that the accumulation of ions favors the lower osmotic potential and contributes to osmotic adjustment inthese halophytes.

关键词： Atriplex sp., salinity stress, osmotic adjustment, ion accumulation, water relations.

PHYTOPLANKTON,ESPECIALLY DIATOMS,IN THE GUT CONTENTS AND FECES OF TWO PLANTIVOROUS CYPRINIDS-SILVER CARP AND BIGHEAD CARP

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Chinese Journal of Oceanology and Limnology 1994年第4期12卷 308-315页

作者：谢平刘建康 Donghu experimental station of Lake Ecosystems Institute of Hydrobiology Chinese Academy of Sciences Wuhan

In order to clarify whether the planktivorous silver carp and bighead carp can collect phytoplanktonas small as Cyclotella(<20μm)in Donghu Lake,studies on phytoplankton in their gut contents and feceswere made in *** fish were cultured in both net cage in Donghu Lake and aquaria with the *** the intestine,the average valve diameter of Cyclotella changed *** average ratio of emptyfrustule of Cyclotella to total Cyclotella in the foregut contents of the fishes were 1.8—1.9 times higherthan that in the lake water,but changed little from foregut to *** aquarium experiment showedthat both carps could collect particles as small as 8-10μm, which was obviously narrower than the dis-tance between their gill ***,secretion of mucus plays an important role in collecting suchsmall

关键词： planktivorous fishes gut contents and feces diatoms valve diameter empty frustule

Changes in the patterns of inorganic nitrogen and TN/TP ratio and the associated mechanism of biological regulation in the shallow lakes of the middle and lower reaches of the Yangtze River

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Science China Earth Sciences 2006年第Z1期49卷 126-134页

作者： WU Shikai XIE Ping WANG Songbo ZHOU Qiong Donghu experimental station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

The changes of NH3-N, NO3-N, NO2-N and TN/TP were studied during growth and non-growth season in 33 subtropical shallow lakes in the middle and lower reaches of the Yangtze River. There were significant positive correlations among all nutrient concentrations, and the correlations were better in growth season than in non-growth season. When TP＞0.1 mgL-1, NH3-N increased sharply in non-growth season with increasing TP, and NO3-N increased in growth season but decreased in non-growth season with TP. These might be attributed to lower dissolved oxygen and low temperature in non-growth season of the hypereutrophic lakes, since nitrification is more sensitive to dissolved oxygen and temperature than antinitrification. When 0.1 mgL-1＞TP＞0.035 mgL-1, TN and all kinds of inorganic nitrogen were lower in growth season than in non-growth season, and phytoplankton might be the vital regulating factor. When TP＜0.035 mgL-1, inorganic nitrogen concentrations were relatively low and NH3-N, NO2-N had significant correlations with phytoplankton, indicating that NH3-N and NO2-N might be limiting factors to phytoplankton. In addition, TN/TP went down with decline in TP concentration, and TN and inorganic nitrogen concentrations were obviously lower in growth season than in non-growth season, suggesting that decreasing nitrogen (especially NH3-N and NO3-N) was an important reason for the decreasing TN/TP in growth season. The ranges of TN/TP were closely related to trophic level in both growth and non-growth seasons, and it is apparent that in the eutrophic and hypertrophic state the TN/TP ratio was obviously lower in growth season than in non-growth season. The changes of the TN/TP ratio were closely correlated with trophic levels, and both declines of TN in the water column and TP release from the sediment were important factors for the decline of the TN/TP ratio in growth season.

关键词： nitrate-nitrogen, ammonium-nitrogen, nitrite-nitrogen, shallow lakes, phytoplankton.

experimental STUDIES ON THE ROLE OF PLANKTIVOROUS FISHES IN THE ELIMINATION OF MICROCYSTIS BLOOM FROM DONGHU LAKE USING ENCLOSURE METHOD

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Chinese Journal of Oceanology and Limnology 1996年第3期14卷 193-204页

作者：谢平 Donghu experimental station of Lake Ecosystems CERN Institute of Hydrobiology Chinese Academy of Sciences Wuhan

The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.

关键词： enclosure experiments water bloom hypertrophic lake planktivorous fishes grazing pressure