安徽省土壤固碳潜力及有机碳汇(源)研究

利用安徽省多目标区域地球化学调查获取的土壤全碳和有机碳数据,采用"单位土壤碳量"方法计算土壤碳储量以及土壤固碳潜力。结果显示,研究区表层(0~0.2 m)土壤固碳量潜力为237.48 Mt,其中土壤有机碳固碳量潜力为141.67 Mt,土壤无机碳固碳量潜力为95.81 Mt;中层(0~1.0 m)土壤固碳量潜力为1104.61 Mt,其中土壤有机碳固碳量潜力为469.32 Mt,无机碳固碳量潜力为635.28 Mt。与全国第二次土壤普查比较,近30年间区内表层土壤有机碳储量增加了7.07 Mt,本区表层土壤有机碳总体为"碳汇"区。碳汇区主要分布在江淮分水岭(六安—滁州一线)以北地区;碳源区则分布于淮河以北固镇县周围及淮河沿岸局部地区。此项工作为进一步探讨安徽省土壤固碳能力及土壤固碳减排潜力提供科学依据。     

不同施肥对春玉米源库特征及其关系的影响

采用田间小区试验方法研究了不同氮、磷、钾肥用量对春玉米源、库特征及源库关系的影响。试验设氮、磷、钾肥处理各4个(氮、磷、钾肥用量分别为:N:0、120、240、360kghm-2;P2O5:0、75、150、225kghm-2;K2O:0、120、240、360kghm-2)。研究结果表明,当N用量为240kghm-2、P2O5用量为150kghm-2、K2O用量为240kghm-2时,春玉米的叶绿素含量、叶面积指数、干物质积累量等源特性和穗粒数、百粒重、产量、经济系数等库特性均高于其它处理;表征源库关系的茎鞘物质输出率处于相对较低的水平,粒叶比最低。因此在N、P2O5、K2O用量分别为240kghm-2、150kghm-2、240kghm-2时既可以保持较高的叶源性能,又能促进籽粒库容的增大,能够获得协调的源库关系。     

上海农田生态系统碳源汇时空格局及其影响因素分析

以1990—2009年上海市农作物产量、农田面积、农业投入等相关统计数据为依据,对上海农田生态系统主要碳源汇进行了测算,分析了上海农田生态系统碳源汇的时空变化特征,并探讨了农田生态系统碳源汇的影响因素。结果表明,1999—2009年上海农田生态系统碳吸收总量总体处于逐步下降趋势,且经济作物和果蔬作物碳吸收比例分别下降和上升明显;碳排放总量则呈逐步下降并趋于稳定的趋势,农用化学品投入是其主要排放源;单位面积碳吸收和排放量则一直处于波动状态。2009年上海各区县农田生态系统碳吸收量、碳排放量和单位耕地面积碳吸收量均为远郊大于近郊,而单位耕地面积碳排放量则为近郊大于远郊。碳源汇影响因素相关性分析表明,碳吸收与粮食作物和经济作物产量显著正相关,而与果蔬作物产量显著负相关;碳排放与农用化学品投入和燃料动力使用以及耕作灌溉管理均显著正相关。     

Assessment of Luffa cylindrica as Support in Biofilms Reactors for the Biological Treatment of Domestic Wastewater

A simultaneous treatment of BOD, phosphorous and ammonia in artificial wastewater was carried out in biofilm reactors with Luffa cylíndrica as organic support and compared with PVC's support under variations of dissolved oxygen of 1.5 a 3.0 mg l^?1 in the same reactor. During semicontinous treatment, the removal of BOD (92.5%) with Luffa cilíndrica was higher than PVC support (80%). Nitrification only existed at levels of oxygen of 3 mg l^?1, showed in the effluent a final concentration of ammonium of 17 and 19 mg l^?1 for Luffa cilíndrica and PVC support, respectively. In reactors with Luffa cilíndrica a higher percentage of P removal (40%) was reached, while no elimination in reactors with PVC was observed. The formation of anaerobic-aerobic zones inside the natural support probably allowed the increase in the efficiency of removal of phosphorous. Oxidation of organic matter, P removal and nitrification can be achieved with the variation of oxygen inside of the same biofilm reactor using L. cylindrical as support material.     

半干旱采煤塌陷区植被土壤碳循环及源、汇功能转换特征

以大柳塔矿区采煤塌陷前后不同草地为研究对象,以区域实测数据为基础,分析了0—80cm土层土壤有机碳储量变化以及春季、夏季、冬季3个季节不同植被部位以及土壤碳循环差异及碳源/汇功能转换特征。结果表明:(1)对照区和沉陷区不同季节土壤碳储量都具有明显的垂直分布特征,采煤沉陷造成春季草地生态系统土壤碳储量显著下降(P=0.001),随季节变化呈现出冬季夏季春季的趋势;(2)采煤沉陷造成草地生态系统春季地上立枯和枯落物碳储量显著上升(P=0.000,P=0.004),冬季枯落物和根系碳储量下降(P=0.016,P=0.015),沉陷区不同植被部位碳储量随季节变化均呈现出春季夏季冬季的趋势;(3)相较对照区,沉陷区植被碳储量随季节变化均表现为碳源过程,土壤碳储量随季节变化由碳源—碳汇过程转变为碳汇过程;(4)相关分析显示,对照区地上新鲜植被碳储量和立枯碳储量呈现出显著的负相关性(P0.05),而沉陷区地上新鲜植被碳储量和立枯碳储量呈现出极显著的正相关性(P0.01)。     

Organic Fertilizer Source and Application Method Impact Ammonia Volatilization

ABSTRACT

Ammonia (NH₃) volatilization from fertilizer applications reduces efficiency and poses environmental hazards. This study used semi-open static chambers to measure NH₃ volatilization from organic fertilizers (feather meal, blood meal, fish emulsion, cyano-fertilizer) to evaluate the impacts of fertilizer source, application method, and rate on NH₃ volatilization. In 2014, two application rates (28 and 56 kg N ha^?1) were applied to lettuce (Lactuca sativa L.). Solid fertilizers (feather meal, blood meal) were preplant applied in a subsurface band, whereas liquid fertilizers (fish emulsion, cyano-fertilizer) were applied weekly through drip irrigation beginning two weeks after transplanting. In 2015, a single application rate (28 kg N ha^?1) was applied to cucumber (Cucumis sativus L.). Solid fertilizers were applied in either subsurface or surface bands. There was a significant difference in NH₃ volatilization among fertilizers, but there was little difference between application rates. Liquid fertilizers had lower NH₃ emissions than solid fertilizers due to their timing and placement. In 2014, blood meal at 56 kg N ha^?1 and feather meal at both rates had the highest NH₃ fluxes. In 2015, surface-banded blood and feather meal had the highest NH₃ fluxes. Fertilizer decisions for organic systems should consider NH₃ emission losses and practices for their reduction.     

A Novel High Capacity Biofilm Reactor System for Treatment of Domestic Sewage

A lab-scale novel biofilm reactor system, Ultra-Compact Biofilm Reactor (UCBR), was studied to investigate its performance and operational characteristics for domestic sewage treatment. The reactor was operated at four different hydraulic retention times, namely, 90, 60, 30 and 15 min. The operating ranges of volumetric loading rates in terms of COD, BOD₅, NH⁺ ₄-N and TKN were 5.6-62.1 kg COD/m³ d, 2.6-32.5 BOD₅/m³ d, 0.6-3.2 kg NH⁺ ₄-N/m³ d and 0.82-6.2 kg TKN/m³ d, respectively. The COD, BOD₅ and NH⁺ ₄-N removal efficiencies at 90-min hydraulic retention time (HRT) and 60-min HRT could exceed 80%, 90% and 99%, respectively. The corresponding maximum biomass concentrations were 12.0 g/L and 15.0 g/L at 90-min HRT and 60-min HRT, respectively. At 30-min HRT, the biomass concentration increased to a maximum of 24.0 g/L. However, COD and BOD₅ removal efficiencies decreased to 75% and 80%, respectively, while the NH⁺ ₄-N nitrification efficiency decreased to only 25% to 30%. These observations suggested that high biomass concentration alone was not sufficient to provide a high removal capacity in a UCBR. Further reduction in HRT to 15 min led to an excessive biomass decline from 22.5 g/L to 4.0 g/L. On the whole, the UCBR was able to sustain COD removal and NH⁺ ₄-N conversion of up to 5.96-18.70 kg COD/m³ d and 0.73-1.00 kg NH⁺ ₄-N/m³ d, respectively.     

Accumulation of Inorganic and Organic Pollutants by Biofilms in the Aquatic Environment

In a partly urbanized catchment to the south of Trier, Germany, short term variations in river sediment compounds as well as the bioaccumulation of pollutants on surface associated microbial coatings (biofilms) were investigated weekly during a period of six months. Concentrations of selected heavy metals (Cu, Zn, Pb), polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and for microbial characterisation protein, carbohydrate and uronic acid were analyzed. Sorption processes on biofilms were determined by temporal variations in pollutants and microbial parameters and through the comparison of sorbed substances in biofilms and sediments. The results show, that sorption events on biofilms play an important and dynamic role in spring and summer for transport and accumulation of the investigated pollutants in the aquatic environment. The amount of pollutants sorbed on sediment particles is not only dependent on the particulate bound or solved pollutants in the river water, but is strongly controlled by the changing conditions of the biofilms.     

安徽省干旱灾害监测及决策支持系统应用

本文对利用NOAA气象卫星遥感监测资料和土壤水分人工观测资料开展安徽省干旱监测的指标进行了介绍.针对干旱灾害预警服务,重点阐述了干旱灾害决策支持系统（DSS）的组成、实现方法,尝试采用决策支持系统实现安徽省干旱灾害的推理诊断和决策服务.     

SWAT模型及其在水环境非点源污染中的应用研究进展

非点源污染是水环境污染的主要来源之一,其过程机理复杂,应用水环境污染模型模拟是研究非点源污染的重要手段.SWAT模型是国际上著名的分布式流域水环境模型之一,结合了遥感(RS)、地理信息系统((GIS)技术,能够准确、长时间段连续地模拟复杂流域的各种水环境过程以及气候变化、土地利用类型、管理措施对流域水平衡和非点源污染的影响,为监测、评价、研究流域水环境非点源污染状况提供了强大的支持平台.在大量调研国内外相关文献的基础上,围绕模型的主要标志性改进及应用成果介绍了SWAT模型的发展历程和现状,论述了模型应用于水环境非点源污染研究的几个主要方面和国内外研究新进展,分析了目前国内应用SWAT模型进行水环境非点源污染研究存在的问题,并对SWAT非点源污染子模型的发展趋势做了展望,以推广这一先进模型在国内的应用范围,提高非点源污染模拟、监测、评价工作的效率及结果的可靠性.     

Physiological and Nutritional Evaluation of the Application of Phosphite as a Phosphorus Source in Cucumber Plants

The aim of this study was to determine how different phosphite and phosphate rates applied together affect the growth and morphology parameters in cucumber plants as well as to characterize the nutritional and physiological state of phosphorus (P). Different foliar application rates of phosphite were applied to analyze subsequent biomass production, the relative growth rate, morphological parameters, P bioindicators, P forms, and P-use efficiency. The data suggest that the application of phosphite as a P fertilizer at a rate of ≥0.5 mM would be an appropriate and effective strategy under suboptimal conditions of phosphate in the growth medium, represented by 0.5 mM in our work, as it improved the growth parameters, number of flowers, leaf area, nutritional state of P, incorporation of P in structural organs, and P-use efficiency by the plant. The results indicate that the validity of the foliar use of phosphite as a P fertilizer in cucumber plants was subject to phosphate availability in the culture medium.     

流域农业非点源污染研究概况

本文对有关非点源污染的概念作了简要介绍,并从流域内非点源污染物浓度与负荷、影响因素及机理、预测与评价、模型化以及控制与管理等方面,介绍了以流域为单位的农业非点源污染研究概况。     

Land Application of Lake-Dredged Materials for Bahiagrass Establishment in the Subtropical Beef Pasture

Background  The continued need to dredge lakes, rivers, and canals in Florida, both for maintenance and environmental improvement, will produce millions of cubic meters of dredged materials. Productive disposal options of lake-dredged materials (LDM) may provide substantial and intangible benefits that will enhance the environment, community, and society. Objective  The objective of this study was to assess lake-dredged materials from Lake Panasoffkee as soil amendment for early establishment of bahiagrass (BG,Paspalum notatum Flügge) in subtropical beef cattle pasture at Sumter County, Florida. Results and Discussion. This study encompassed two phases: Phase 1 comprised of five small observation plots (0.3 x 0.3 m); Phase 2 consisted of five larger test plots (30.5 x 30.5 m). Each of the plots in Phase 1 and Phase 2 had a different ratio LDM to natural soil (NS): Plot 1 (0% LDM + 100% NS); Plot 2 (25% LDM + 75% NS); Plot 3 (50% LDM + 50% NS); Plot 4 (75% LDM + 25% NS); and Plot 5 (100% LDM + 0% NS). Each plot was seeded with BG and early growth and yield establishment were monitored for 16 weeks. Conclusion  Results disclosed significantly taller (p ≤ 0.001) plants and higher biomass production (p ≤ 0.001) of BG from plots amended with 75% LDM than those of BG planted on plots with 0% LDM. Results suggest that LDM can serve as source of lime and fertilizer to establish BG beef pasture fields. Sediments with high CaCO₃ improved the physical and chemical conditions of subtropical beef pastures. Lake-dredged materials could be removed from the spoil containment areas, trucked to other locations, and incorporated into existing fields for agricultural uses. There is still much to be learned, but it is certain that Lake Panasoffkee sediments should be regarded as a resource, with no observed harmful ecological effects. Recommendation and Outlook  The agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficial resource, as a part of the ecological system. This study has been continued for several years to explore and assess the long term efficacy of LDM on productivity and quality of BG beyond its early establishment stage. Joint contribution of the USDA-ARS and the Florida Agricultural Experiment Station, Journal Series No, R-09253.     

Application of a Gaussian Plume Model to Determine the Location of an Unknown Emission Source

A concept called equipotential pollution source is introduced assuming that the Gaussian Plume model completely describes the dispersion of pollutants in the atmosphere. For a given wind direction and atmospheric stability category, wherever an emission source might lie on the curve, the ratio of the concentrations at chosen sampling sites lying in the downwind direction would bne the same. A method is developed to describe the curve. The point of intersection of two such curves gives the location of the unknown source. It is discussed that simultaneous control of pollutants with known and unknown sources would ensure better adaption of the Gaussian Plume model and hence better results. The method might be effective in the determination of a transboundary emission source.     

Oxygen Transfer and Industrial Wastewater Treatment Efficiency of a Vertically Moving Biofilm System

A vertically moving biofilm system (VMBS) was developed to treat wastewater. In this system, the biofilm grows on a biofilm module consisting of plastic media that is vertically and repeatedly moved up into the air and down into the water. The objectives of this study were to investigate the oxygen transfer efficiency and industrial wastewater treatment performance of the VMBS. The oxygen transfer coefficient (K _L a) depended on the movement frequency (n) of the biofilm module and was proportional to n ^1.67. K _L a values measured were within the range of 0.0001 to 0.0027 s^-1. The VMBS exhibited good carbonaceous removal when treating industrial wastewater produced in a factory manufacturing synthetic fibres. Removal efficiency of filtered chemical oxygen demand (COD) and biological oxygen demand (BOD₅) was up to 93.2 and 97.9%, respectively. The volumetric removal rates of filtered COD and BOD₅ reached 1320 g COD m^-3 day^-1 and 700 g BOD₅ m^-3 day^-1. The areal organic removal rates, based on the surface area of the biofilm substrata, were 16 g BOD₅ m^-2 day^-1 and 39 g COD m^-2 day^-1. No clogging occurred during the experiment. The mean areal biofilm mass increased with increasing the mean areal BOD₅ removal rate. The new biofilm process has such advantages as high carbonaceous oxidation, energy saving, simpleconstruction and easy operation for industrial wastewater treatment.     

Soil Respiration and Biogenic Carbon Dioxide Sink in the Territory of Russia: An Analytical Review

Studies on the assessment of soil respiration and ecosystem CO₂ sink in the territory of Russia are reviewed over the period since the adoption of the United Nations Framework Convention on Climate Change (Rio de Janeiro, 1992). The first estimates of total soil respiration in the entire territory of Russia, made in 1995 to 1998, amount to 3.1 and 4.3 Gt C per growing season and per year, respectively. On average, soil CO₂ efflux over the cold season (November–March) accounts for 20–30% of annual efflux. The contribution of heterotrophic respiration (R _H ) to the total soil respiration (R _S ) may reach 30–70%, depending on ecosystem type. Despite differences in methods used to measure R _H , the results obtained by different authors vary within a relatively narrow range, from 2.9 to 3.5 Gt C/year at an uncertainty level of about 20%. The soil cover of Russia (11.7% of the global land area) accounts for 6.3% of global soil CO₂ efflux. The data on ecosystem CO₂ sink are widely scattered among publications. Estimates of carbon balance differ depending on approaches and methods used to determine its individual components and the level of uncertainty in the results. However, most of them confirm the main conclusion: the territory of Russia with its forests is an absolute CO₂ sink with a potential of 200 Mt C/year. This conclusion has been corroborated in the absolute majority of studies performed by Russian and international research teams.     

概率配点法在流域非点源污染不确定性分析中的应用

农业非点源污染的形势十分严峻,流域水环境模型虽能为非点源污染管理提供决策支撑,但显著的不确定性制约着模型的应用效果。系统的不确定性分析十分重要,而传统的基于Monte Carlo模拟的不确定性分析方法存在着计算成本高昂的缺点。因此,尝试将概率配点法（Probabilistic Collocation Method）应用于流域非点源污染的不确定性分析。研究以美国Newport Bay流域的二嗪磷农药非点源污染为案例,利用WARMF模型进行污染模拟。结果表明,在许多情况下,概率配点法可以通过很小的计算成本获得与传统Monte Carlo模拟方法相近的不确定性分析结果,体现出该方法在非点源污染研究中应用的优势。此外,还揭示了管理因素对于非点源污染模拟及其不确定性分析的影响作用。