《Pedosphere》收录时间：2019-02-15作者：Arturo GARCA-SALDAA , Cesreo LANDEROS-SNCHEZ , María del Refugio CASTAEDA-CHVEZ , Juan Pablo MARTNEZ-DVILA , Arturo PREZ-VZQUEZ , Eugenio CARRILLO-VIL
There are very few studies on the application of fertilizers through irrigation water(fertirrigation) using a multi-gate irrigation system in sugarcane AES. Through fertirrigation, the application of fertilizers can be simplified, and their distribution uniformity in sugarcane fields improved. This paper provides an overview of the state of the art regarding fertirrigation with multi-gate irrigation in sugarcane agroecosystems(AES). In order to systematize, organize, and discuss the scientific data on fertirrigation with low-pressure multi-gate irrigation systems in sugarcane AES, bibliographic material from the following full-text scientific journal databases was screened: the Elsevier Science Direct Freedom Collection, Springer Link, and the International Society for Horticultural Science. Next,a matrix of keywords was used to analyze the interrelationships among the available literature, current issues, and the recent findings.We conclude that development of fertirrigation technologies with low-pressure multi-gate irrigation is much needed.
《Pedosphere》收录时间：2019-02-15作者：DENG Yusong , SHEN Xue , XIA Dong , CAI Chongfa , DING Shuwen , WANG Tianwei
In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland,leading to reduced nutrients, increased erodibility, and even desertification. The aim of this study was to investigate soil erodibility(the factor K in the Universal Soil Loss Equation, USLE) and physicochemical properties of the alluvial fans of the most severe collapsing gully erosion areas(Hubei, Jiangxi, Fujian, and Guangdong provinces) in southern China. The soils of the collapsing gully alluvial fans had a higher bulk density, but a lower total porosity, saturated water content, and silt and clay fractions than the control(CK) soils from the farmland without desertification. Soil quality gradually decreased from fan edge to fanhead. Significant decreases were found in soil p H, organic matter, cation exchange capacity, and total potassium, nitrogen, and phosphorus, as well as available nitrogen, phosphorus, and potassium, resulting in a gradual decrease in soil nutrients from the fanedge to the fanhead. Soil erodibility was greatest in the fanhead, and soil erodibility K values of the alluvial fans were 53.71%, 66.28%, 67.53%, and 71.68% greater than that in those of the CK soils of Hubei, Jiangxi, Fujian, and Guangdong, respectively, indicating a significant correlation between the soil erodibility K values and physicochemical properties, particularly sand fraction and organic matter content. The results provide new insights into the relationship between soil physicochemical properties and erodibility of alluvial fans, and suggest that improving soil structure might increase soil fertility in the collapsing gully alluvial fan farmland.
《Pedosphere》收录时间：2019-02-15作者：Cinisani M.TFWALA , Leon D.van RENSBURG , Zaid A.BELLO , Pieter C.ZIETSMAN
Dear Editor,Accurate measurement of volumetric soil water content (θ_v) is essential for efficient soil water management. HydraSCOUT (HS) probes are capacitance-type probes for θ_v measurement with high accuracy, but require calibration for different soil types. We aimed to
《Pedosphere》收录时间：2019-02-15作者：CHEN Xu , WEI Xiaorong , HAO Mingde , ZHAO Jing
Iron(Fe) deficiency in calcareous soils of the Loess Plateau of China is a wide spread issue and primarily affects agricultural production due to the relatively higher soil pH and carbonate content. Understanding the relationships between Fe distribution in soil fractions, Fe availability, and their responses to cropping and fertilization could provide essential information for assessing Fe availability in soils and managing soils to improve Fe availability. A long-term field experiment was established in 1984 in a split-plot design using cropping systems as main plots and fertilizer treatments as subplots on a farmland in the Loess Plateau. The cropping systems included fallow, continuous wheat cropping, continuous alfalfa cropping, continuous maize cropping, and a rotation system that included a legume. Various fertilization treatments using chemical and/or manure fertilizers were included in each cropping system. Soil samples were collected from 0–10 and 20–40 cm depths in 2012. Long-term planting of crops significantly increased the concentrations of available Fe in the soils. The largest increase was observed in the continuous alfalfa cropping system. Long-term cropping significantly increased the concentrations of Fe associated with carbonates and organic matter, but decreased the concentration of Fe associated with minerals in the soils. The effect of fertilization on the distribution of Fe in the soil fractions varied with cropping system and soil depth. The fertilization treatment with manure generally increased the concentrations of Fe associated with the soil fractions.Long-term cropping and fertilization in the highland farmland significantly affected the availability of Fe and the distribution of Fe fractions in the soil.
《Pedosphere》收录时间：2019-02-15作者：WU Di , FENG Yanfang , XUE Lihong , LIU Manqiang , YANG Bei , HU Feng , YANG Linzhang
Organic amendments such as vermicompost and biochar have been reported to enhance soil fertility and crop productivity.However, whether the co-application of both amendments has synergistic effects or whether such benefits are accompanied by the risk of gaseous nitrogen（N） loss in an agroecosystem remains unknown. A soil column experiment with a fully factorial design was conducted using three levels of vermicompost（no dose, low dose（1%, weight:weight）, and high dose（3%, weight:weight）） without or with biochar（1%, weight:weight） to investigate their effects on rice growth and gaseous N loss across the crop growing season. Our results demonstrated that synergistic interactions existed between vermicompost and biochar in promoting crop yield. Compared with biochar amendment alone, biochar combined with vermicompost significantly（P < 0.01） increased rice yield by 26.5%–35.3%. However,high dose of vermicompost significantly（P < 0.01） increased the cumulative ammonia（NH3） and nitrous oxide（N2O） emissions. In the presence of vermicompost, the incorporation of biochar amendment significantly（P < 0.01） decreased the cumulative N2O emission by 14.1%–18.6%. The lowest emission factor value of NH3 and N2O was achieved using biochar in combination with low dose of vermicompost. This study revealed that the combination of biochar and moderate dose of vermicompost offers a novel approach to promote crop productivity while reducing the environmental risk.
《Pedosphere》收录时间：2019-02-15作者：Natalia MóRTOLA , Romina ROMANIUK , Vanina COSENTINO , Maximiliano EIZA , Patricia CARFAGNO , Pedro RIZZO , Patricia BRES , Nicolás RIERA , Marcos ROBA , Mariano BUTTI , Daiana SAINZ , Lucrecia BRUTTI
Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical composition and pathogen content in a digestate from poultry manure, according to international regulations, and 2) the effect of its soil application on the major chemical and biological soil properties and on the growth of Lactuca sativa. The experiment consisted of two groups of pots（with and without crop）. Treatments applied to each group were as follows: low and high doses of digestate and inorganic fertiliser, and no application（control）(low dose: 70 kg nitrogen（N） ha-1 and 21 kg phosphorus（P） ha-1; high dose: 210 kg N ha-1 and 63 kg P ha-1). Soil samples were taken 7 and 34 d（harvest） after treatment applications. Heavy metal and pathogen contents in the digestate were below the upper limit values. Despite the high pH and electrical conductivity values of the digestate, both soil parameters presented acceptable values for crop growth. Although there were no initial increases in total inorganic N and available P in soil with digestate application, an increase in the fresh weight of crop was observed with the high dose application. This is probably associated with the slow nutrient release from the digestate during the development of the crop. Changes in the microbial community were temporary and occurred at the initial sampling stage of the experiment.
《Pedosphere》收录时间：2019-02-15作者：Dorsaf KERFAHI , Binu M.TRIPATHI , Johan W.Ferry SLIK , Rahayu S.SUKRI , Salwana JAAFAR , Ke DONG , Matthew Chidozie OGWU , Hyo-Ki KIM , Jonathan M.ADAMS
White sand heath forests(WS) or kerangas, an unusual variant of tropical forests in Borneo, characterized by open scrubby vegetation, low productivity, and distinctive plant species composition and soil microbial community, are regarded as a stressful lowpH and/or nutrient environment. We investigated whether the functional soil metagenome also shows a predicted set of indicators of stressful conditions in WS. Based on stress-tolerant strategies exhibited by larger organisms, we hypothesized that genes for stress tolerance, dormancy, sporulation, and nutrient processing are more abundant in the soil microbiota of WS. We also hypothesized that there is less evidence of biotic interaction in white sand soils, with lower connectivity and fewer genes related to organismic interactions. In Brunei, we sampled soils from a WS and a normal primary dipterocarp forest, together with an inland heath, an intermediate forest type. Soil DNA was extracted, and shotgun sequencing was performed using Illumina HiSeq platform, with classification by the Metagenomics Rapid Annotation using Subsystem Technology(MG-RAST). The results, on one hand, supported our hypothesis(on greater abundance of dormancy, virulence, and sporulation-related genes). However, some aspects of our results showed no significant difference(specifically in stress tolerance, antibiotic resistance, viruses, and clustered regularly interspaced short palindrome repeats(CRISPRs)). It appears that in certain respects, the extreme white sand environment produces the predicted strategy of less biotic interaction, but exhibits high soil microbiota connectivity and functional diversity.
《Pedosphere》收录时间：2019-02-15作者：ZHANG Meijun , FENG Meichen , XIAO Lujie , SONG Xiaoyan , Guangwei DING , YANG Wude
The persistence of Cry1 Ac protein in the soil and its effect on soil microbial communities are a core issue in assessing the ecological risk of transgenic Bacillus thuringiensis(Bt) cotton. In this study a field experiment was conducted on the cultivation of transgenic Bt cotton(Jin 26 and BtJ i 668) with the immediate returning of residues to the fields, in order to quantify the Cry1 Ac protein content in the fields and investigate its effects on the functional diversity of soil microbial communities. Cry1 Ac protein in the residue-soil mixture was gradually degraded in the transgenic Bt cotton fields. After transgenic Bt cotton straw was returned to the fields for 30 d, 63.73%and 58.33% of the initial amounts of Cry1 Ac protein were degraded in the Jin 26 and BtJ i 668 fields, respectively. Before the crops were sown in the following year(180 d after returning the straw), no Cry1 Ac protein was detected in the fields. After returning the cotton straw to the fields for 30 d, the Shannon-Wiener and McIntosh indices of soil microbial communities in the transgenic Bt cotton fields were significantly higher than those in the non-transgenic cotton fields. Meanwhile, the utilization of carbon sources including amino acids, amines, and carbohydrates by the soil microbial communities significantly increased. Both the McIntosh index and the utilization of carbohydrates increased until 180 d. Principal component analysis revealed that amino acids, amides, and carbohydrates were the main carbon sources distinguishing the two principal component factors. These findings indicated that Cry1 Ac protein did not accumulate in the fields after transgenic Bt cotton was planted for one year and the residues were immediately returned to the fields; however, the original functional diversity of soil microbial communities was affected continuously.
《Pedosphere》收录时间：2019-02-15作者：Katja BOLDT-BURISCH , Bernd Uwe SCHNEIDER , M.Anne NAETH , Reinhard F.HTTL
Nutrient-poor, sandy soils form the prevailing substrate at post-mining sites of the Lusatian region(Brandenburg, Germany) and present a challenge for vegetation development. We studied the organic acid quantity and composition of three commonly occurring pioneer plant species, the legumes Lotus corniculatus L. and Trifolium arvense L. and the grass Calamagrostis epigeios(L.) Roth, to determine if plant growth and exudation differed with(non-sterilized soil) and without(sterilized soil) an indigenous soil microbial community. We investigated whether organic acids were found in the rhizosphere and surrounding soil and whether this influenced nutrient mobilization. This study consists of linked field investigations and a greenhouse experiment. Plants were grown in the greenhouse in either sterilized or non-sterilized sandy soil from a reclamation site in the Lusatian mining landscape(Welzow Su¨d, East Germany). After seven months, the plant biomass, root morphology, organic acids, and water-soluble nutrients and root colonization with arbuscular mycorrhizal fungi(AMF) and dark septate endophytes(DSE) were analyzed. Roots of all three plants in the field and greenhouse experiments were highly colonized with AMF. Calamagrostis epigeios and T. arvense had a significantly higher colonization frequency with DSE than L. corniculatus. The quantity and composition of organic acids strongly differed among plant species, with the highest number of organic acids found for L. corniculatus and lowest for C. epigeios. The quantity of organic acids was greatly reduced in all plants under sterilized soil conditions. However, the composition of organic acids and plant growth in sterilized soil were reduced for both legumes, but not for C. epigeios, which had a higher biomass under sterilized conditions. Changes in nutrient concentrations in the field rhizosphere soil relative to those in the control were measurable after seven months. While the spectrum of organic acids and the growth of legumes seemed to be dependent on a highly diverse soil microbial community and a symbiotic partner, the grass C. epigeios appeared capable of mobilizing enough nutrients without an indigenous microbial community, and might be more competitive on sites where soil microbial diversity and activity are low.
《Pedosphere》收录时间：2019-02-15作者：DONG Xingchen , ZHANG Jian , QIU Huizhen , ZHANG He , LUO Chaoyue , DENG Delei , SHEN Qirong , JIA Zhongjun
Nitrogen（N） application may lead to niche segregation of soil ammonia-oxidizing archaea（AOA） and bacteria（AOB）, thereby reducing the competitive interactions between AOA and AOB due to higher ammonium substrate availability. However, the adaptive mechanisms of AOA and AOB under N enrichment remain poorly understood. Stable isotope probing（SIP） microcosm incubation was employed to reveal community changes of active AOA and AOB in a loess soil from a field experiment growing potatoes that received no N（control, CK）, low N(LN, 75 kg N ha-1), and high N(HN, 375 kg N ha-1). The results showed that the soil potential nitrification rate（PNR） was measured by culturing of the soil samples from the field experiment. Soil PNR was significantly increased in HN by87.5% and 67.5% compared with CK and LN, respectively. Compared with CK, the13C-amoA genes of soil AOA and AOB in HN had 2.58 × 104 and 1.55 × 106 copies, representing 1.6-and 16.2-fold increase respectively. It was indicated that AOB dominated soil ammonia oxidation. A phylogenetic analysis of the13C-amoA gene showed that N application significantly increased the proportion of54 d9-like AOA up to 90% in HN, while the Nitrososphaera gargensis-like and Nitrososphaera viennensis-like AOA were inhibited and completely disappeared. Nitrogen application also resulted in the community shift of active AOB-dominant group from Nitrosospira briensis-like to Nitrosospira sp. TCH711-like. Our study provides compelling evidence for the emergence and maintenance of active nitrifying communities under the intensified N input to an agricultural ecosystem.