重庆喜获＂国家园林城市＂殊荣

近日,国家住房和城乡建设部正式公布2009年国家园林城市、县城和城镇评审结果,决定命名重庆市等41个城市为国家园林城市,重庆市荣昌县、重庆市云阳县等31个县城为国家园林县     

＂八大盒＂提升项目建管水平

多年来,资料不齐全、不完备一直是项目建设管理中的一个顽疾。为此,我省国家水土流失重点治理工程根据项目建设管理办法及有关规范性文件要求,结合不同部门、不同专业人员的检查评估要求,按照“系统性、完整性、准确性、真实性”原则,分类归档、完善资料,从八个方面对内业资料进行系统整编,简称“八大盒”。具体为：基本文件资料盒、设计资料盒、监理资料盒、招投标资料盒、施工资料盒、建设管理资料盒、财务资料盒、竣工资料盒。     

重庆实施＂阳光工程＂帮助农民工转移就业

为应对金融危机对农民工就业带来的不利影响,2009年以来,重庆通过创新机制实施阳光工程,加大政府财政投入,顺利帮助20余万农民工实现转移就业。     

我国＂三品一标＂农产品总量稳步增长

无公害农产品、绿色食品、有机农产品和地理标志农产品是我国安全优质农产品的主导品牌。据农业部统计．2011年1－5月．我国“三品一标”继续保持快速发展态势，总量稳步扩大，质量稳定可靠，市场影响力明显增强。     

奉新县早稻＂万亩高产创建示范片＂建设成效及措施

2010年,根据江西省农业厅〈江西省2010年粮棉油高产创建项目实施方案〉文件精神,结合江西省奉新县粮食生产发展实际情况.多措并举,该县全力开展早稻＂万亩高产创建示范片＂工作,将其作为发展粮食生产的核心工作紧抓不放,努力扩大创建规模、提高创建质量、增强辐射影响,取得了明显的成效.     

发挥山区种植优势实现玉米优质高产——壶关县实施玉米＂万亩高产创建示范片＂建设的对策与经验

壶关县地处山西省东南部,太行山东南端,是一个典型的农业大县、生态强县和旅游名县.全县辖12个乡镇1个经济开发区,390个行政村,总面积1013km〈＇2〉,其中耕地面积2.37万hm2,总人口30万人,其中农业人口26.5万人.2010年,壶关县承担了农业部＂万亩玉米高产创建示范片＂的建设任务.在组织实施和具体实践中,紧紧围绕＂高产、优质、高效、生态、环保＂的工作原则,以科学发展为引领,以示范建设为依托,以转变方式为抓手,确保了玉米高产品种的推广应用,提升了玉米增密技术的适用范围,实现了全县粮食产量的持续高产.     

贵州省赫章县野马川镇“五园新村＂生态建设成效初探

赫章县野马川镇在“五园新村”生态建设中，从毕节试验区实际情况出发，问计于民，按照“全省重点整治村庄”、“和谐家园”、“三化同步”等产业发展思路，把产业发展作为城镇重点建设内容之一，因地制宜，着力抓好在全县生态文明家园建设点上的产业发展规划和试点示范，带动群众走上小康之路。     

农业部提出“十二五＂期间水产品质量安全工作总体思路

6月13日．农业部在四川省成都市召开了全国水产品质量安全管理工作会议。农业部副部长牛盾在会上强调．“十二五”期间水产品质量安全管理工作的总体思路是，坚决贯彻党中央、国务院对食品安全工作的战略部署．树立科学监管理念．按照立足当前、着眼长远、标本兼治、重在治本的工作原则，着力完善体制机制，延伸基层监管网络，     

农业部公益性行业科研专项“核技术在高效、低碳农业中的应用＂项目执行交流会、中国原子能农学会八届五次常务理事会及《核农学报》编委会会议在河南郑州同期召开

2012年4月11-12日,由中国原子能农学会主办,河南省科学院同位素研究所有限责任公司承办的农业部公益性行业科研专项”核技术在高效、低碳农业中的应用”项目执行交流会、中国原子能农学会八届五次常务理事会及《核农学报》编委会会议在河南省郑州市龙源大酒店成功召开。共有包括项目参加单位负责人及相关学者、学会常务理事会成员及《核农学报》编委在内的90余位代表分别出席了会议。河南省科学院院长郭新和、纪委书记李海现、河南省科技厅政策法规与基础研究处处长杨梦琳及河南省农学会秘书长冯天福出席大会开幕式并致辞。     

Priming effect and its regulating factors for fast and slow soil organic carbon pools: A meta-analysis

The priming effect (PE) plays a critical role in the control of soil carbon (C) cycling and influences the alteration of soil organic C (SOC) decomposition by fresh C input.However,drivers of PE for the fast and slow SOC pools remain unclear because of the varying results from individual studies.Using meta-analysis in combination with boosted regression tree (BRT) analysis,we evaluated the relative contribution of multiple drivers of PE with substrate and their patterns across each driver gradient.The results showed that the variability of PE was larger for the fast SOC pool than for the slow SOC pool.Based on the BRT analysis,67%and 34%of the variation in PE were explained for the fast and slow SOC pools,respectively.There were seven determinants of PE for the fast SOC pool,with soil total nitrogen (N) content being the most important,followed by,in a descending order,substrate C:N ratio,soil moisture,soil clay content,soil pH,substrate addition rate,and SOC content.The directions of PE were negative when soil total N content and substrate C:N ratio were below 2 g kg~(-1)and 20,respectively,but the directions changed from negative to positive with increasing levels of this two factors.Soils with optimal water content (50%–70%of the water-holding capacity) or moderately low pH (5–6) were prone to producing a greater PE.For the slow SOC pool,soil p H and soil total N content substantially explained the variation in PE.The magnitude of PE was likely to decrease with increasing soil pH for the slow SOC pool.In addition,the magnitude of PE slightly fluctuated with soil N content for the slow SOC pool.Overall,this meta-analysis provided new insights into the distinctive PEs for different SOC pools and indicated knowledge gaps between PE and its regulating factors for the slow SOC pool.     

Environmental risks for application of iron and steel slags in soils in China: A review

Iron and steel slags are smelting wastes, mainly including blast furnace slag(BFS) and steel slag(SS) produced in the iron and steel industry. Utilization of iron and steel slags as resources for solving the problem of slag disposals has attracted much attention with increasing iron and steel smelting slags in China. Because the iron and steel slags contain calcium(Ca), magnesium(Mg), phosphorus(P), and silicon(Si), some have tried to use them as Si-and P-fertilizers, for producing Ca-Mg-P fertilizers, or as soil amendments in agriculture. However, in the iron metallurgical process, several pollutants in iron ores can inevitably transfer into iron and steel slags, resulting in the enrichment of pollutants both in BFS(mainly nickel(Ni), copper(Cu), mercury, zinc(Zn),cadmium(Cd), chromium(Cr), arsenic, lead, selenium, fluorine(F), and chlorine(Cl)) and in SS(mainly Ni, Cr, Cd, Zn, Cu, F, and Cl), in which some of pollutants(especially Cr, Ni, F, and Cl) exceed the limits of environmental quality standards for soils and groundwater. The elements of manganese, barium,and vanadium in iron and steel slags are higher than the background values of soil environment. In order to ensure soil health, food safety, and environmental quality, it is suggested that those industrial solid wastes, such as iron and steel slags, without any pretreatment for reducing harmful pollutants and with environmental safety risk, should not be allowed to use for soil remediation or conditioning directly in farmlands by solid waste disposal methods, to prevent pollutants from entering food chain and harming human health.     

A review of cadmium sorption mechanisms on soil mineral surfaces revealed from synchrotron-based X-ray absorption fine structure spectroscopy: Implications for soil remediation

The sorption of cadmium(Cd) is one of the most important chemical processes in soil, affecting its fate and mobility in both soil and water and ultimately controlling its bioavailability. In order to fundamentally understand the sorption/desorption of Cd in soil systems, X-ray absorption fine structure spectroscopy(XAFS) has been applied in numerous studies to provide molecular-level information that can be used to characterize the surface adsorption and precipitation reactions that Cd can undergo. This information greatly improves our current knowledge of the possible chemical reactions of Cd in soil. This paper critically reviews the mechanisms of Cd sorption/desorption at the mineral-water interface based on XAFS studies performed over the past twenty years. An introduction to the basic concepts of sorption processes is provided, followed by a detailed interpretation of XAFS theory and experimental data collection and processing,ending finally with a discussion of the atomic/molecular-scale Cd sorption mechanisms that occur at the soil mineral-water interface. Particular emphasis is placed on literature that discusses Cd adsorption and speciation when associated with iron, manganese, and aluminum oxides and aluminosilicate minerals.Multiple sorption mechanisms by which Cd is sorbed by these minerals have been found, spanning from outer-sphere to inner-sphere to surface precipitation,depending on mineral type, surface loading, and pH. In addition, the application of complementary techniques(e.g.,113 Cd nuclear magnetic resonance(NMR) and molecular dynamics simulation) for probing Cd sorption mechanisms is discussed. This review can help to develop appropriate strategies for the environmental remediation of Cd-contaminated soils.     

大宁党参高产栽培技术

党参因产地及加工方法不同,有不同的商品名。巫溪称"大宁党"、巫山称"巫山党"、"单支党"、"条党"、"庙党",奉节称"条党"。巫溪所产党参是川党参(C.tangshen Oliv.)中的一种,即"大宁党",其名称来源于产地命名(巫溪县在明国时期为大宁县),在植物学分类上为"条党",即产于重庆、湖北、陕西交界处的党参,其形状多条状,故名"条党"。     

Human and ecological risks of metals in soils under different land-use types in an urban environment of Bangladesh

Trace metal contamination in soil is of great concern owing to its long persistence in the environment and toxicity to humans and other organisms.Concentrations of six potentially toxic trace metals,Cr,Ni,Cu,As,Cd,and Pb,in urban soils were measured in Dhaka City,Bangladesh.Soils from different land-use types,namely,agricultural field,park,playground,petrol station,metal workshop,brick field,burning sites,disposal sites of household waste,garment waste,electronic waste,and tannery wast,and construction waste demolishing sites,were investigated.The concentration ranges of Cr,Ni,Cu,As,Pb,and Cd in soils were 2.4–1258,8.3–1044,9.7–823,8.7–277,1.8–80,and 13–842 mg kg^-1,respectively.The concentrations of metals were subsequently used to establish hazard quotients(HQs)for the adult population.The metal HQs decreased in the order of As>Cr>Pb>Cd>Ni>Cu.Ingestion was the most vital exposure pathway of studied metals from soils followed by dermal contact and inhalation.The range of pollution load index(PLI)was 0.96–17,indicating severe contamination of soil by trace metals.Considering the comprehensive potential ecological risk(PER),soils from all land-use types showed considerable to very high ecological risks.The findings of this study revealed that in the urban area studied,soils of some land-use types were severely contaminated with trace metals.Thus,it is suggested that more attention should be paid to the potential health risks to the local inhabitants and ecological risk to the surrounding ecosystems.     

Importance of hydrogenotrophic, aceticlastic and methylotrophic methanogenesis for methane production in terrestrial, aquatic and other anoxic environments: A mini review

Microbial methanogenesis is a major source of the greenhouse gas methane(CH4).It is the final step in the anaerobic degradation of organic matter when inorganic electron acceptors such as nitrate,ferric iron,or sulfate have been depleted.Knowledge of this degradation pathway is important for the creation of mechanistic models,prediction of future CH4 emission scenarios,and development of mitigation strategies.In most anoxic environments,CH4 is produced from either acetate(aceticlastic methanogenesis)or hydrogen(H2)plus carbon dioxide(CO2)(hydrogenotrophic methanogenesis).Hydrogen can be replaced by other CO2-type methanogenesis,using formate,carbon monoxide(CO),or alcohols as substrates.The ratio of these two pathways is tightly constrained by the stoichiometry of conversion processes.If the degradation of organic matter is complete(e.g.,degradation of straw in rice paddies),then fermentation eventually results in production of acetate and H2 at a ratio of>67%aceticlastic and<33%hydrogenotrophic methanogensis.However,acetate production can be favored when heterotrophic or chemolithotrophic acetogenesis is enhanced,and H2 production can be favored when syntrophic acetate oxidation is enhanced.This typically occurs at low and elevated temperatures,respectively.Thus,temperature can strongly influence the methanogenic pathway,which may range from 100%aceticlastic methanogenesis at low temperatures to 100%hydrogenotrophic methanogenesis at high temperatures.However,if the degradation of organic matter is not complete(e.g.,degradation of soil organic matter),the stoichiometry of fermentation is not tightly constrained,resulting,for example,in the preferential production of H2,followed by hydrogenotrophic methanogenesis.Preferential production of CH4 by either aceticlastic or hydrogenotrophic methanogenesis can also happen if one of the methanogenic substrates is not consumed by methanogens but is,instead,accumulated,volatilized,or utilized otherwise.Methylotrophic methanogens,which can use methanol as a substrate,are widespread,but it is unlikely that methanol is produced in similar quantities as acetate,CO2,and H2.Methylotrophic methanogenesis is important in saline environments,where compatible solutes are degraded to methyl compounds(trimethyl amine and dimethyl sulfide)and then serve as non-competitive substrates,while acetate and hydrogen are degraded by non-methanogenic processes,e.g.,sulfate reduction.     

Combined application of a straw layer and flue gas desulphurization gypsum to reduce soil salinity and alkalinity

Burying a straw layer and applying flue gas desulphurization(FGD)gypsum are effective practices to ameliorate soil salinization or alkalization and to increase crop yield;however,little information exists on the effects of such integration in saline-alkali soils.A soil column experiment was conducted to investigate the effects of a straw layer plus FGD gypsum on soil salinity and alkalinity.We placed a straw layer(5 cm thick)at a depth of 30 cm and mixed FGD gypsum into the 0–20 cm soil layer at application rates of 7.5,15.0,22.5,and 30.0 t ha^-1,with no straw layer and FGD gypsum as a control(CK).The soil water content in the 0–30 cm soil layer was significantly higher(>7.8%)in the treated soil profiles after infiltration than in the CK,but decreased after evaporation.The electrical conductivity(EC)of the 10–30 cm soil layer was 230.2%and 104.9%higher in the treated soil profiles than in the CK after infiltration and evaporation,respectively,and increased with increasing rates of FGD gypsum application,with Ca^2+and SO4^2-being the main dissolved salts.Compared to those in the CK,the concentrations of Na^+,Cl^-,and HCO3-decreased in the treated soil profiles at depths above 55 cm,but the other soluble ions increased,after infiltration.A similar trend occurred after evaporation for all soluble ions except for HCO3-.The p H and exchangeable sodium percentage in the treated soil profiles were significantly lower than those in the CK over the entire profile,and decreased with increasing FGD gypsum application rates.Therefore,the incorporation of a straw layer plus FGD gypsum can reduce salinity and alkalinity,but the quantity of FGD gypsum should be controlled in saline-alkali soils.     

Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

Measuring ammonia(NH₃)volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in agriculture.The small area of chambers used for NH₃volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are adopted.Our aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH₃volatilization in urea-amended field plots and ii)to define the critical period of NH₃-N losses during which the concentration of sampling effort is capable of reducing uncertainty.The use of only one chamber covering 0.015%of the plot(51.84 m²)generates a value of NH₃-N loss within an expected margin of error of 30%around the true mean.To reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per plot.Concentrating the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH₃volatilization.This strategy enhances the power of detection of NH₃-N loss abatement in field experiments using chambers.     

Distribution of 137Cs and 60Co in plough layer of farmland: Evidenced from a lysimeter experiment using undisturbed soil columns

Radionuclide fallout during nuclear accidents on the land may impair the atmosphere, contaminate farmland soils and crops, and can even reach the groundwater. Previous research focused on the field distribution of deposited radionuclides in farmland soils, but details of the amounts of radionuclides in the plough layer and the changes in their proportional distribution in the soil profile with time are still inadequate. In this study, a lysimeter experiment was conducted to determine the vertical migration of 137Cs and 60Co in brown and aeolian sandy soils, collected from the farmlands adjoining Shidaowan Nuclear Power Plant(NPP) in eastern China, and to identify the factors influencing their migration depths in soil. At the end of the experiment(800 d), >96% of added 137Cs and 60Co were retained in the top 0–20 cm soil layer of both soils;very little 137Cs or 60Co initially migrated to 20–30 cm, but their amounts at this depth increased with time. The migration depth of 137Cs was greater in the aeolian sandy soil than in the brown soil during 0–577 d, but at the end of the experiment, 137Cs migrated to the same depth(25 cm) in both soils. Three phases on the vertical migration rate(v) of 60Co in the aeolian sandy soil can be identified: an initial rapid movement(0–355 d, v = 219 ± 17 mm year-1), followed by a steady movement(355–577 d, v = 150 ± 24 mm year-1) and a very slow movement(577–800 d, v = 107 ± 7 mm year-1). In contrast, its migration rate in the brown soil(v = 133 ± 17 mm year-1) was steady throughout the 800-d experimental period. The migration of both 137Cs and 60Co in the two soils appears to be regulated by soil clay and silt fractions that provide most of the soil surface area, soil organic carbon(SOC), and soil pH, which were manifested by the solid-liquid distribution coefficient of 137Cs and 60Co. The results of this study suggest that most 137Cs and 60Co remained within the top layer(0–20 cm depth) of farmland soils following a simulated NPP accident, and little reached the subsurface(20–30 cm depth). Fixation of radionuclides onto clay minerals may limit their migration in soil, but some could be laterally distributed by soil erosion and taken up by crops, and migrate into groundwater in a high water table level area after several decades.Remediation measures, therefore, should focus on reducing their impact on the farmland soils, crops, and water.     

青花菜品种在南亚热带地区的适宜性研究

青花菜又称绿叶菜,原产于地中海沿岸,其特点是营养价值高,含有多种矿物质等营养,位居同类蔬菜之首。由于青花菜生育期短,耐寒性强,主要产区在北方,在南方只有冷凉地区有少量栽培,而贵州属典型的南亚热气候类型,特别是在罗甸地区,秋季作物收获后,冬季只种植一些白菜类蔬菜。而营养价值高的青花菜,     

南疆阿拉尔垦区海岛棉耗水规律研究

通过对7个海岛棉品种土壤水分动态变化分析研究,结果表明,不同品种各生育期土壤含水量、土壤蓄水量存在极显著差异.所有品种土壤含水量在不同土层的变化趋势基本一致,呈现出"Z"字型的规律性变化.即随土层深度的增加,土壤含水量逐渐减少,80-100 cm土层土壤含水量又升高.含水量最高的土层是0-20 cm,最低的土层是60-80 cm.这种规律性变化与棉花生长特点、根系的发育特点以及吸收特点有关.534、IZ181、新海21是节水型品种,能够较充分利用有限的灌溉水,在干旱半干旱地区具有强大的优势.