Teil II: Stoffstromnetze für Fruchtfolgen

The general results of material flow analyses for agricultural farms presented in Part I are now specified for three farms in Lower Saxony. For this, the existing material flow net for winter wheat is extended by the crops of winter barley, winter rye, summer barley, rape, sugar beets and potatoes. The assessment is essentially done regarding the impact categories of resource depletion, cumulated energy demand (CED) and emissions to atmosphere. Besides the assessment of single farms or crops, also the comparison, of different agricultural production systems is possible, whereby the choice of the functional unit and the basis of comparison (with reference to input or output) is of major importance. Additionally, as for agricultural means of production, the material flows and emissions resulting from the provision of carbolime — an often employed carbonate fertiliser as for sugar-beet cultivation — are derived completely within this article. Furthermore, sensitivity analyses on the subject of detail intensity of agricultural basic data are presented for the example of machine employment. The material flow nets are regarded as transferable to other farms with similar crop rotation systems, with an appropriate expenditure of information gathering and parameterisation. The complete net can be used as a module within further investigations, e.g. of the industrial processing of food, as a pre-production chain for agricultural resources being part of the production process (winter wheat — mill, brewing barley — brewery, sugar beets — sugar-factory).     

Life cycle assessment of the winter wheat-summer maize production system on the North China Plain

A life cycle assessment (LCA) method was used to examine the environmental impact of the winter wheat-summer maize production system on the North China Plain. The LCA considered the entire system required to produce 1 ton each of winter wheat and summer maize. The analysis included raw material extraction and transportation, agrochemical production and transportation, and arable farming in the field. First, all emissions and resource consumption connected to the different processes were listed in a life cycle inventory (LCI) and related to a common unit (1 ton of grain). Subsequently, a life cycle impact assessment (LCIA) was conducted, in which the inventory data were aggregated into indicators for environmental effects, including energy depletion, climate change, acidification, aquatic eutrophication, human toxicity, aquatic and terrestrial ecotoxicity. For winter wheat systems, energy depletion and acidification were the most relevant environmental impacts, and energy depletion and aquatic eutrophication were the primary concerns for summer maize systems. The results revealed that the most important source of environmental impact in the winter wheat-summer maize production system in Huantai County was the production and application of nitrogen fertilisers. The environmental impacts of winter wheat were much stronger than those of summer maize due to higher inputs and lower use efficiency of agrochemicals.     

Gasförmige Stickstoffemissionen im Lebensweg von Getreide zur Energiebereitstellung

The reduction of energy-based environmental pollution is a declared goal of governmental action in all industrialised countries. In this context, the aim of this paper is to investigate the emissions of volatile nitrogen species with regard to their resulting environmental impacts by the example of the heat provision from whole cereal crops as a substitute for light oil products. First, the applied methodology of a Life Cycle Assessment is discussed. The emissions of volatile nitrogen species and their resulting environmental impacts are subsequently quantified putting a special focus on the emissions of gases from biogenic sources in the agroecosystem. The comparison of heat provision based on whole cereal crops versus light oil over the entire life cycle shows that heat from biomass results in a lower environmental impact regarding the anthropogenic greenhouse effect, but a higher one with respect to eutrophication, acidification and the depletion of the stratospheric ozone layer. These results may change if the energy crops are produced extensively during agricultural processes, if other mitigation measures are undertaken or if the emissions from the combustion in the biomass-fired boiler are reduced.     

Development and test of a crop growth model for application within a Global Change decision support system

When examining potential impacts of Global Change on water resources on the regional scale, spatial and temporal changes in crop water and nitrogen demand are of fundamental significance. State-of-the-art crop growth models are powerful tools to assess the response of crops to altered environmental conditions and cultivation practices. In this paper, the process-based, object-oriented and generic DANUBIA crop growth model is presented. To evaluate the performance of the model, a validation analysis is carried out by comparing modelled data with various field measurements of sugar beet, spring barley, maize, winter wheat and potato crops. Model performance statistics show that crop growth is efficiently simulated. The closest agreement between measured and modelled biomass and leaf area index is achieved for sugar beet and winter wheat. Additionally, the response of the model to changed nitrogen availability caused by cultivation practices is analysed and reveals good results. The results suggest that the model is a suitable tool for numerically assessing the consequences of Global Change on biomass production, water and nitrogen demand, taking into account the complex interplay of water, carbon and nitrogen fluxes in agro-ecosystems.     

不同灌溉方式冬小麦农田生态系统碳平衡研究

全球气候变暖趋势明显,陆地生态系统碳循环的研究成为目前的研究热点,而农田生态系统是陆地生态系统的重要组成部分,由于农田生态系统是受人类强烈调节与控制的复合系统,其碳循环受各类农作措施的影响极大。新疆地处干旱区,水分条件是农田碳循环的最重要限制因子。为此,分析不同灌溉方式对冬小麦（Triticum aestivuml）农田生态系统碳平衡的影响,从而提出有利于新疆冬小麦生产的固碳减排的灌溉方式。试验于2012—2013年在伊宁县科技示范园冬小麦试验田进行,选择伊农18冬小麦品种为供试材料,确定滴灌和漫灌为两个试验主因子并设置小区。试验自冬小麦返青开始至完全成熟结束,期间平均每7天采1次样,其中用典型样株法采集小麦植株,分根、茎、叶等不同器官单独烘干测定植株固碳量;用静态钠石灰吸收法测定冬小麦土壤呼吸;收集整理已发表国内外文献中的各类碳排放参数确定本研究中所需参数;采用王小彬的碳平衡计算方法分析不同灌溉方式农田生态系统碳平衡,据此对滴灌和漫灌两种灌溉方式的冬麦农田作物生物量固碳、土壤碳排放量和作物生产过程中物质投入的间接碳排放量,以及两种灌溉方式下冬麦农田生态系统净碳值进行分析。试验结果表明：滴灌条件下冬麦农田生态系统小麦的固碳量、土壤碳排放总量分别比漫灌小麦的高出15.38%和11.43%,冬小麦穗是差异形成的主要原因;而农业生产资料排碳总量比漫灌少排3.88%;但无论是滴灌还是漫灌,耗电碳排放量均占农业生产资料碳排放总量的59%以上,是农业生产资料碳排放的第一大来源。两种灌溉方式下冬小麦田生态系统的净碳值均呈现出固碳并存在显著差异（p〈0.01）,且滴灌冬麦农田生态系统净碳值比漫灌高25.39%。因此,新疆冬小麦生产中采用滴灌方式更有利于农田生态系统的固碳,     

Simulating the yields of bioenergy and food crops with the crop modeling software BioSTAR: the carbon-based growth engine and the BioSTAR ET0 method

Background

With a growing production and use of agricultural substrates in biogas facilities, the competition between food and energy production, environmental issues, and sustainability goals has seen an increase in the last decade and poses a challenge to policy makers. Statistical yield data has a low spatial resolution and only covers standard crops and makes no statement in regard to yields under climate change. To support policy makers and regional planners in an improved allocation of agricultural land use, a new crop model (BioSTAR) has been developed.

Results

Simulations with weather and yield data from 7 years and four regions in Lower Saxony have rendered overall good modeling results with prediction errors (RMSE and percentage) ranging from 1.6 t and 9.8% for winter wheat to 2.1 t and 11.9% for maize. The model-generated ET₀ and ET_a values (mean of four locations) are lower than ET₀/ET_a values calculated with the Penman-Monteith method but appear more realistic when compared to field trial data from northern and eastern Germany.

Conclusions

The model has proven to be a functioning tool for modeling site-specific biomass potentials at the farm level, and because of its Access® database interface, the model can also be used for calculating biomass yields of larger areas, like administration districts or states. Out of the seven crops modeled in this study, only limited yield and test site data was available for winter barley, winter rye, sorghum, and sunflower. For further improvement of model performance and model calibration, more trial data and data testing are required for these crops.     

An application of Markov Decision Programming to ecologico-cybernetics—A decision method applied to the antifrost of winter wheat

Modern ecologico-cybernetic principle is of importance to decreasing damages in relation to agricultural productions. As an illustration of this, the authors studied some of the questions about the optimal policy of choosing actions for the antifrost measures of winter wheat by means of the finite-stage model of Markov Decision Programming (MDP). The related data came from the investigation results of the investigated region in the northeastern part of Henan, China. First, the authors give the states, ecologico-cybernetic action measures, transition probabilities and reward values in relation to these antifrost action measures of winter wheat crop. Second, the authors describe the principles and computational procedures of the ecologico-cybernetic decision-makings based on the finite-stage model of MDP. Third, a simple table applicable to the decision-making practice is given. Finally, we evaluate the results of this study, point out their shortcomings and suggest that this method is applicable to the other fields in relation to decreasing damage ecologico-cybernetics.     

Systematische Exploration stoffbezogener Umweltproblematiken

With the aim of providing results for precautionary environmental politics at an early point in time, a strategy is being sought to optimize the identification of research objects in substance-related environmental research. Both, proven as well as potential substance risks are considered as such. This approach is meant to support pro-active elements in environmental chemistry (as opposited to re-active elements associated with environmental damage). In the atmosphere, substance risks are created by perturbations of functions of the atmosphere and of other natural spheres, as far as atmospheric functions are part of the cause-effect relationships. A complete risk assessment includes exposure and effects analyses, a prerequisite for the latter is the identification of critical effect thresholds (in general: criticalities). However, the state of knowledge in many cases does not allow for a quantitative analysis of the cause-effect relationships. Exposure analysis can be significant for the identification of relevant research objects, because the quantification of the spatial and temporal extent of the potential damage constitutes an important risk category which can be addressed by exposure analysis. Examples for priority issues of substance-related environmental research are given based on combined exposure and effect analyses, as well as on exposure analyses alone. References for the knowledge production process in substance-related environmental science are provided in the field of risk assessment and using the syndrome concept.     

Teil V: Bewertung landwirtschaftlich-industrieller Stoffströme

Agricultural and industrial production chains as product lines are connected and their assessment is performed for a varnish based on linseed oil that is almost completely composed of renewable raw materials. Using a production line analysis, the ecological and social effects of the production are assessed, and different assessment techniques for ecological assessment are used as well. The life cycle inventory results from a material flow analysis including pre-production chains. For optimisation, a scenario of conventional agricultural linseed oil production against ecologically produced linseed oil is assessed. All assessment methods identify the same aspect of the product as the most important: The content of volatile organic compounds (VOC), that are released during usage. Further problems such as waste in the oil mill, emittance of acidic substances (mostly NO_x) from burning and heavy metals from tinplate production for containers are identified only from one or another of the assessment methods, a feature which stresses the influence on results from the choice of method. All methods prefer the ecological production of linseed, but the significance regarding the system boundaries is low (0.6% UBP, 1.7% Eco-indicator) due to dominating VOC-emissions. The use of material flow analyses in LCA is possible for agricultural production, especially seamless connection is provided between the different production steps. Also parameterisation is easy so that the defining of scenarios is efficient and transparent.     

A study on the spatial distribution of nitrogen and phosphorus balance, and regional nitrogen flow through crop production

The spatial distribution patterns of the nitrogen and phosphorus input/intake amounts in crop production within two small basins are examined, based upon a cropping unit distribution map that is obtained from remote sensing data analysis. Firstly, we examine the availability and suitability of approaches to the spatial distribution analysis of cultivation patterns classified from material flow characteristics of crop production using seasonal remote-sensing data. Secondly, material flow units in crop production are grouped according to the cultivation patterns obtained from the remote-sensing data analysis. Consequently, the spatial patterns of the amounts of both nitrogen and phosphorus inputs/intakes through crop production on farmland are examined and their spatial distribution maps are prepared according to the material flow units. In addition, we developed a nitrogen flow and runoff model and the model is simulated based on the examination of the results of spatial distribution patterns of the material flow units. The annual nitrogen runoff from small catchments, where various crops are cultivated, varies from 2.7 kg ha(-1) year(-1) to 108 kg ha(-1) year(-1) and the annual balanced losses of nitrogen in small catchments varied from -30 kg ha(-1) year(-1) to 101 kg ha(-1) year(-1). Also, the monthly changes in soil nitrogen of each material flow unit is estimated at -55 kg ha(-1) as a maximum decrease and 114 kg ha(-1) as a maximum increase. These results indicate that the spatial distribution patterns of nutrient input and intake through agricultural activities should be considered when analyzing the material flows and nutritient movement in soil-water systems in rural areas for watershed environmental control and regional agricultural management.     

Runoff water management technologies for dryland agriculture on the Loess

SUMMARY

Arid and semi-arid environments undergo periodic seasonal agricultural droughts of varying extents and duration, erratic and ineffective rainfall of high intensity and short duration, with high surface runoff. High efficiency water-harvesting agriculture has been routinely used in the Loess Plateau agricultural production of China over the past 10 years. Localized habitat effect and regional water resource enrichment are the theoretical basis of high efficient water-harvesting agriculture. Features of this agricultural system are described, including: water harvesting of surface runoff from roads and collection in concrete yards on plastic sheets; water storage cellar tanks for harvesting runoff to provide life-saving/critical irrigation, with devices for water lifting and conveying such as hand pumps and pipelines; feasible methods of water use for limited supplies such as drip, hole, subsoil, and super-sheet irrigation; agronomic measures of high water use efficiency; and field micro-catchment for water harvesting and conservation to increase fallow efficiency in rainy seasons. Using the stored runoff water to irrigate the mulched winter wheat and spring corn, as well as vegetables and fruit trees, significant yield increasing and water use efficiency improvements have been achieved. Plastic mulching for increasing fallow efficiency in rainy seasons and improving yield of the next winter wheat crop have been developed and demonstrated. These techniques have provided obvious benefits in terms of soil and water conservation on slope farmland in the hill regions and remarkable effects of storing water and reducing drought in the dryland farming regions have been obtained.     

Untersuchungen zur Eignung von Neutralsalzen als Referenzmittel bei der mikrobiologisch-ökotoxikologischen Bewertung von Pflanzenschutzmitteln im Boden

Goal and Scope

The information value of microbiologicalecotoxicological investigations of pesticides in soil increases if reference compounds with known biocidal effects are included. But those reference compounds used until now often are of remarkable environmental and human toxicity and therefore are difficult to handle. Inorganic neutral salts sometimes were discussed as alternatives, but their suitability needs to be tested before.

Methods

For laboratory experiments some microbial activities in soil were selected whose effects had been proved in several microbiological-ecotoxicological investigations. They include the mineralization of carbon and nitrogen (+ nitrification) as well as the biomass-related parameters dehydrogenase activity and substrate-induced short-term respiration. Several agricultural soils were used to confirm the results.     

Teil III: Stoffstromanalyse

A material flow analysis is performed to check the measures of groundwater protection, especially those undertaken to reduce nitrate leaching in water protecting areas. The impacts both of direct and of indirect agricultural processes are assessed. Implementing the methodology of cost counting into the material flow analysis allows one to test whether the equalization payments (agreed on in voluntary agreements between farmers and water economy for special groundwater protecting measures as direct drilling or intercropping) are appropriate for compensating the resulting economical losses for the farmer. It is shown that this extensive production produces more profit — despite lower yields and inferior quality — due to equalization and lower production costs. However, these results strongly depend on yield estimation. Groundwater protecting measures with low input (e.g. nitrogen reduction) reduce environmental impacts on a regional and also on a global scale, while other measures such as intercropping increase them due to additional fertilizer application. So it is still difficult to choose one or the other because of weighing global against regional effects in a qualitative and quantitative way.     

基于MODIS数据的河南省冬小麦产量遥感估算模型

小麦是世界上最重要的粮食作物,小麦生产对中国的粮食保障起着十分重要的作用,及时、准确、大范围对小麦产量进行监测预报,对于农学经济发展和粮食政策制定具有极为重要的现实意义。对作物产量进行遥感监测的原理是建立在其遥感特征基础之上的,通过建立作物长势指标与遥感信息的定量关系,可实现对作物产量的监测预报。文章基于2009年MODIS遥感数据和气象数据,利用Arcgis和ENVI提取纯小麦像元,并提取纯小麦像元对应的NDVI、NPP和LAI,获取分县NDVI、NPP和LAI均值,利用统计软件对产量数据和分县遥感参数均值进行数据整理和分析,建立了河南省冬小麦产量估算模型。以往研究多采用遥感图像上某像元和地面调查点进行研究,具有很大的不确定性,文章以县为单位,对冬小麦平均单产和县域内冬小麦种植像元遥感参数的均值进行相关研究,提高了模型模拟精度。同时文章选用多种遥感参数和多项气象因子建立估产模型,避免了针对一个参数进行估产的局限性。在最佳时相的选择上,根据冯美辰（2010）以往的研究结果,从4月以后,5月8日和4月20Et植被指数和产量相关性最大,4月份之前冬小麦处于返青到拔节期,对产量来说还有很多不确定闪素,因此文章选用5月8El和4月20日进行冬小麦估产研究。结果表明,5月8日的估产模型优于4月20日,加入气象冈子的遥感气象估产模型优于只采用遥感参数进行估产的遥感模型。利用2010年产量数据对模型精度进行检验,遥感气象模型预测精度在70．2％N99．7％之间,平均精度为90．7％;遥感模型预测精度在68．1％到95．5％之间,平均精度为83．9％。表明遥感气象模型模拟精度更高,其精度可以满足大面积估产要求,可以对产量预报提供科学参考。     

A study on the Spatial Distribution of Nitrogen and Phosphorus Balance, and Regional Nitrogen Flow Through Crop Production

The spatial distribution patterns of the nitrogen and phosphorus input/intake amounts in crop production within two small basins are examined, based upon a cropping unit distribution map that is obtained from remote sensing data analysis. Firstly, we examine the availability and suitability of approaches to the spatial distribution analysis of cultivation patterns classified from material flow characteristics of crop production using seasonal remote-sensing data. Secondly, material flow units in crop production are grouped according to the cultivation patterns obtained from the remote-sensing data analysis. Consequently, the spatial patterns of the amounts of both nitrogen and phosphorus inputs/intakes through crop production on farmland are examined and their spatial distribution maps are prepared according to the material flow units. In addition, we developed a nitrogen flow and runoff model and the model is simulated based on the examination of the results of spatial distribution patterns of the material flow units. The annual nitrogen runoff from small catchments, where various crops are cultivated, varies from 2.7 kg ha^–1 year^–1 to 108 kg ha^–1 year^–1 and the annual balanced losses of nitrogen in small catchments varied from –30 kg ha^–1 year^–1 to 101 kg ha^–1 year^–1. Also, the monthly changes in soil nitrogen of each material flow unit is estimated at –55 kg ha^–1 as a maximum decrease and 114 kg ha^–1 as a maximum increase. These results indicate that the spatial distribution patterns of nutrient input and intake through agricultural activities should be considered when analyzing the material flows and nutritient movement in soil–water systems in rural areas for watershed environmental control and regional agricultural management.     

中国农业领域温室气体主要减排措施研究分析

气候变暖已成不争事实,主要是由于人为温室气体（GHG）排放增加所致,为减缓气候变暖趋势,各领域迫切需要采取减排措施;农业是一个重要的GHG排放源,农业领域采取减排措施对于减少我国GHG排放、保护农村生态环境有重要意义。文章在大量阅读前人研究结果的基础上,总结我国农业领域主要的减排管理措施,主要从农业活动、农村生活和生物质能源利用三方面进行阐述,并简要分析各措施的减排效果和存在问题。分析发现,农业活动的水肥管理是农田温室气体减排的研究热点,但由于地域和管理流程上的差异,对措施的减排效果尚存在争议;农村生活中存在巨大的减排潜力,采取恰当的减排措施不但可以减少GHG排放,还可以改善农村生态状况和环境卫生条件;农村生物质能源有很大发展潜力,合理开发利用,可以有效替代化石能源消耗,缓解能源危机,减少GHG排放,保护生态环境。总之,在农业领域采取积极的减排措施,有助于国家效应对气候变化,降低农业源污染和GHG排放,减轻环境压力,转换农业发展模式,加速农业现代化,促进农业生产的可持续发展和社会主义新农村建设。     

徐州地区主要农产品生产基地土壤环境质量评价

对徐州地区主要农产品生产基地的土壤进行了采样监测 ,对照国家无公害农产品产地的环境质量标准 ,采用单项污染指数法和综合污染指数法对 11个基地土壤的 7项污染指标进行了环境质量评价。结果表明 ,该地区主要农产品生产基地的土壤环境质量总体优良 ,完全能满足目前国家所规定的无公害农产品安全生产的要求     

臭氧和氮肥交互对小麦干物质生产、N、P、K含量及累积量的影响

利用中日合作建立的亚洲首个稻麦轮作开放式臭氧浓度升高（ozone-free air controlled enrichment,O3-FACE）平台,选取小麦品种（Tritcium aestivum）扬麦16为试材,研究了不同臭氧和氮肥水平下,小麦不同部位干物质量以及N、P、K质量分数的变化。结果表明,臭氧胁迫下,常氮水平小麦根、叶和穗干物质量以及根冠比与对照相比均显著降低,降幅分别为37.4%、17.4%、12.8%、29.8%,而增施氮肥后,小麦根叶穗及根冠比与常氮下相比均显著增加,增幅分别为60.5%、23.2%、10.7%、43.6%;常氮条件下,臭氧浓度升高明显降低N、P、K累积量及成熟期叶中N、P、K质量分数,降幅分别为10.93%、11.65%、7.64%、23.87%、14.81%、14.9%,而成熟期穗中N、P、K质量分数明显增加,增幅分别为6.15%、10.34%、13.12%,增施氮肥后,N、P、K累积量及小麦叶中N质量分数与常氮相比明显增加,增幅分别为15.58%、11.91%、9.00%、10.74%,叶中P、K质量分数也有所增加但增幅很小,而增施氮肥对其他部位的N、P、K质量分数影响不大。臭氧和氮肥对茎部干质量及N、P、K质量分数影响均不明显。总之,增施氮肥对小麦在臭氧胁迫下的生物量累积和养分累积有一定的缓解作用。     

O3浓度升高对麦田土壤碳、氮含量和酶活性的影响

近地层O₃作为全球最重要的大气污染物之一,其对作物的生长发育、土壤酶活性、土壤碳、氮的影响机制已成为人们关注的重要问题。采用开顶式气室(OTCs)法模拟研究O₃浓度升高对冬小麦土壤碳、氮含量和酶活性的影响。结果表明,O₃浓度升高导致麦田0~10 cm和10~20 cm土层的全碳(TC)和全氮(TN)含量呈现出下降的趋势。O₃浓度升高对土壤酶活性也有影响。在冬小麦灌浆期,O₃胁迫可促进土壤脱氢酶活性提高。当O₃浓度为120 nL·L^-1时,0~10 cm、10~20 cm和20~40 cm土层的脱氢酶活性分别比对照处理提高59.4%、51.5%和22.2%。O₃胁迫对土壤转化酶活性的影响随着冬小麦生长期和土壤采样深度的不同而发生变化。在冬小麦拔节期,O₃处理对不同土层脲酶活性的影响没有达到显著差异水平,但是在灌浆期,20~40 cm土层的脲酶活性随着O₃浓度的增加而提高,在120 nL·L^-1浓度O₃处理下脲酶活性比对照处理提高24.6%。在O₃胁迫条件下土壤转化酶活性与土壤全碳含量、土壤脲酶活性与土壤全氮含量均呈现出显著的正相关关系。     

基于卫星遥感的秸秆焚烧监测及对空气质量影响分析

每年6月是我国小麦收割的主要时节,也是秸秆焚烧发生的严重时期.利用卫星遥感技术监测2007年6月全国秸秆焚烧状况,并以某市为例,结合气象资料分析秸秆焚烧对环境空气质量的影响.研究结果表明,秸秆焚烧主要分布在冬小麦生产区,华北平原是秸秆焚烧集中区域,火点数占全国的86.9%;秸秆焚烧主要发生在6月上半月,火点数占全月的87.3%.相关分析表明,该市700、800 km范围缓冲区内火点数变化趋势与空气污染指数有较好一致性,相关系数均达0.54,当秸秆焚烧发生在不利于污染物扩散的气象条件下时,将导致空气质量明显下降.