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1.
农业耕作制度变化及其环境效应是国内外广泛关注的学术前沿问题。近60 a来,江苏太湖地区农业耕作制度发生较大变化,主要表现在种植制度从偏重粮食生产转向粮经作物协调发展,用地作物增多而养地作物减少,作物品种经历了改进与优化过程,作物熟制经历了从“双三制”恢复到两熟制。施肥种类从有机肥为主转变为完全施用化肥,氮磷钾肥投入比例从长期严重失调发展到逐渐趋于协调。在总结近60 a来江苏太湖地区农业耕作制度变化特征的基础上,〖JP2〗分析了农业耕作制度变化对地表水土环境的影响,并提出了今后需要进一步关注的研究方向  相似文献   

2.
Environmental impacts have become an important consideration in the manufacturing industry due to increasing public pressure for environment protection and the requirements of recently launched legislations. Data envelopment analysis (DEA) is a widely adopted methodological approach for the benchmarking of the relative efficiency of different production units. Changes in production efficiency may affect environmental impacts. DEA can be used for identifying the most efficient production facility and hence, the environmental impacts generated from the different production lines can then be benchmarked. Life cycle assessment (LCA) is carried out to quantify the full environmental impacts of a product from ‘cradle to grave’. The integration of LCA with DEA, efficiency and environmental impact of different production processes for a certain family of products can be evaluated and benchmarked. The proposed two-stage approach can help to reduce the aggregate environmental impacts of the manufacturing phase and is used to benchmark the environmental performance of several production lines in a manufacturing company.  相似文献   

3.
Sub-Saharan African countries are being strongly urged to enhance their rice production, because their rice consumption and importation rates have been rapidly increasing in recent years. Areas planted to rice in Africa are classified agro-ecologically into rainfed upland, rainfed lowland, and irrigated. Rainfed lowland includes extensive areas of unexploited land that has great potential for the promotion of rice growing. For the unexploited rainfed lowlands of Ghana, we have been studying the development of low-cost rice-farming systems that require no large-scale irrigation or land reclamation. For such systems, it is important to select suitable areas where water for rice farming can be obtained naturally; floodwaters offer promise for this purpose. Delineation and mapping of floodwater prone areas suitable for rice production is important for successful utilization of this land resource. Here, we propose a method of assessing flood probability from submergence frequency, as estimated from satellite imagery and geospatial data. ALOS/PALSAR images acquired in May, June, August, and September 2010 were used to classify land and water, and then a submerged-area map was produced. From the results, we were able to accurately detect non-submerged areas and submerged areas with water depths of at least 3?cm. The number of times classified into submerged area was defined as submergence frequency, and it was approximated by distance from reservoirs representing White Volta River, ponds, and swamps. In addition, flood extent derived from reservoirs was simulated using digital elevation model (DEM). Finally, a flood probability assessment map was produced by integration of the estimated submergence frequency and flood extent simulation. The results of a comparison of soil moisture data measured at 69 points in the field and the NDVIs computed by ALOS/AVNIR showed that areas with high potential for flooding retained high levels of soil moisture and were more likely to show less deterioration of vegetation in the dry season. The validation of these results confirmed the adequacy of the flood probability assessment method.  相似文献   

4.
Sustainable development requires methods and tools to measure and compare the environmental impacts of human activities for the provision of goods and services (both of which are summarized under the term "products"). Environmental impacts include those from emissions into the environment and through the consumption of resources, as well as other interventions (e.g., land use) associated with providing products that occur when extracting resources, producing materials, manufacturing the products, during consumption/use, and at the products' end-of-life (collection/sorting, reuse, recycling, waste disposal). These emissions and consumptions contribute to a wide range of impacts, such as climate change, stratospheric ozone depletion, tropospheric ozone (smog) creation, eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources, water use, land use, and noise-among others. A clear need, therefore, exists to be proactive and to provide complimentary insights, apart from current regulatory practices, to help reduce such impacts. Practitioners and researchers from many domains come together in life cycle assessment (LCA) to calculate indicators of the aforementioned potential environmental impacts that are linked to products-supporting the identification of opportunities for pollution prevention and reductions in resource consumption while taking the entire product life cycle into consideration. This paper, part 1 in a series of two, introduces the LCA framework and procedure, outlines how to define and model a product's life cycle, and provides an overview of available methods and tools for tabulating and compiling associated emissions and resource consumption data in a life cycle inventory (LCI). It also discusses the application of LCA in industry and policy making. The second paper, by Pennington et al. (Environ. Int. 2003, in press), highlights the key features, summarises available approaches, and outlines the key challenges of assessing the aforementioned inventory data in terms of contributions to environmental impacts (life cycle impact assessment, LCIA).  相似文献   

5.
Efficient use of energy helps to achieve increased production and productivity and contributes to the economy, profitability, and competitiveness of agricultural sustainability of rural communities. Evaluation of wheat and barley production systems in view of energy balance was conducted in Khorasan Razavi Province, Iran. Data were collected by using a face-to-face questionnaire from wheat and barley fields in 2011. Results revealed that total energy input for wheat was 51,040 MJ ha?1 and for barley 44,866; in wheat and barley systems, renewable energy was consumed by 25.43 and 23.53 %, while non-renewable energy was consumed by 74.57 and 76.47 %, respectively. Energy use efficiency, energy productivity, and net energy were 1.7 kg MJ?1, 0.088 kg MJ?1, and 35,987 MJ ha?1 in wheat system and 1.83 kg MJ?1, 0.092 kg MJ?1, and 33,833 MJ ha?1 in barley system, respectively. Energy intensiveness in wheat fields (61.84 MJ $?1) was higher than in barley fields (58.71 MJ $?1). Also, benefit-to-cost ratio in wheat system (1.59) was higher than in barley system (1.35). In general, production in barley fields was more sustainable than wheat production because, in view of ecological indices such as amount of energy use and renewable energy consumption, it was more environment-friendly production.  相似文献   

6.
安徽省粮食生产的主成分分析及其趋势预测   总被引:2,自引:0,他引:2  
采用安徽省1978~2010年的相关社会经济统计资料为基础数据,在对33 a来粮食动态变化的定量定性分析基础上,利用主成分分析方法探讨了区域粮食生产的影响因子。然后根据安徽33 a粮食总产量的历史数据,建立GM(1,1)预测模型,对安徽省未来20 a(2011~2030年)的粮食产量进行中长期的模拟预测,以期为相关部门粮食生产决策提供科学依据。研究表明:(1)1978~2010年,安徽省粮食生产在波动中增长,粮食总产量和人均粮食产量曲线的动态变化基本吻合。(2)影响粮食生产的3个主要成分分别是社会经济发展水平、农业生产成本和粮食作物播种面积。(3)粮食生产在2011~2030年将保持平稳增长的良性发展态势,2030年粮食预测产量达到4 119万t,比2010年增长了1 039万t,年均增长15%。〖HJ1〗〖HJ〗  相似文献   

7.
This article describes a study of the environmental impacts of the use of industrial agricultural chemicals in four Asian countries—China, India, the Philippines and Thailand. The objective was to contribute objectively to the discussion on the extent of the problem, past and current damages to the environment to and outline possible paths to sustainable and environmentally benign agriculture. The four countries are experiencing rapid economic growth under a tremendous population growth pressure that, with the exception of China, will continue without leveling of in a foreseeable future. This requires more food production that has been accomplished by the increased use of industrial chemical fertilizers. Although the four countries uses of industrial chemicals vary, the mix of nutrients appears to be imbalanced, resulting in large nitrogen losses into the environment, especially in China. A suggested solution of the problem begins with reducing (China) or maintaining (India, the Philippines, Thailand) average nutrient application levels needed by the crops and includes optimal hybrid agriculture by using organic fertilizers, and fertilizers in the irrigation water already overloaded with nitrogen. There is a need to balance fertilizer N and P applications with the crop needs.  相似文献   

8.
Agricultural crops are affected by climate change due to the relationship between crop development, growth, yield, CO2 atmospheric concentration and climate conditions. In particular, the further reduction in existing limited water resources combined with an increase in temperature may result in higher impacts on agricultural crops in the Mediterranean area than in other regions. In this study, the cropping system models CERES-Wheat and CROPGRO-Tomato of the Decision Support System for Agrotechnology Transfer (DSSAT) were used to analyse the response of winter durum wheat (Triticum aestivum L.) and tomato (Lycopersicon esculentum Mill.) crops to climate change, irrigation and nitrogen fertilizer managements in one of most productive areas of Italy (i.e. Capitanata, Puglia). For this analysis, three climatic datasets were used: (1) a single dataset (50?km?×?50?km) provided by the JRC European centre for the period 1975–2005; two datasets from HadCM3 for the IPCC A2 GHG scenario for time slices with +2°C (centred over 2030–2060) and +5°C (centred over 2070–2099), respectively. All three datasets were used to generate synthetic climate series using a weather simulator (model LARS-WG). Adaptation strategies, such as irrigation and N fertilizer managements, have been investigated to either avoid or at least reduce the negative impacts induced by climate change impacts for both crops. Warmer temperatures were primarily shown to accelerate wheat and tomato phenology, thereby resulting in decreased total dry matter accumulation for both tomato and wheat under the +5°C future climate scenario. Under the +2°C scenario, dry matter accumulation and resulting yield were also reduced for tomato, whereas no negative yield effects were observed for winter durum wheat. In general, limiting the global mean temperature change of 2°C, the application of adaptation strategies (irrigation and nitrogen fertilization) showed a positive effect in minimizing the negative impacts of climate change on productivity of tomato cultivated in southern Italy.  相似文献   

9.
Precision agricultural fertilization technique at small scale is the key for regional cultivated land protection and management. Taking Dingzhuang Town (located in Guangrao County, Shandong Province) as a case study, this article explores the precision agricultural fertilization technique at small scale. First, three main cropping systems are identified via field investigation, namely wheat–maize–soybean, garlic–maize and cotton. Then, application amount of fertilizer N, P and K under the three cropping sys...  相似文献   

10.
为了探索长江流域双季稻体系氮肥施用对氨挥发损失的影响,评价Denitrification Decomposition (DNDC)模型对产量和氨挥发拟合的适应性,设计了早稻和晚稻不同氮肥用量田间试验,采用密闭室间歇通气法原位观测氨挥发排放通量,利用DNDC模型进行模拟分析,并运用模拟结果探讨了水稻产量和氨挥发损失与施氮量之间的关系。结果显示,模型能较好模拟双季稻体系水稻产量和氨挥发,早稻、晚稻和双季稻产量模拟值与观测值的相关系数分别为0.994、0.928、0.979,早稻、晚稻和整个双季稻生育期氨挥发模拟值与观测值的相关系数分别为0.994、0.998和0.997,均达到极显著水平。DNDC模型能较好预测因施肥引起的氨挥发排放峰,但在氨挥发通量和排放总量的定量上还需要进一步改进。敏感性指数分析表明,气温是影响作物产量的关键因素,氮肥用量和气温是影响氨挥发的主要因素。DNDC模型在模拟双季稻体系籽粒产量上具有较高的可信度,DNDC模拟和田间观测数据计算的最高产量施氮量分别是420和417 kg·hm-2。稻田氨挥发损失量与施氮量之间满足二次函数和线性关系,二次函数能更好描述两者之间的关系。为使DNDC更准确的进行估算和应用,有必要获取更翔实的环境资料以减少输入数据的不确定性。  相似文献   

11.
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.  相似文献   

12.
长江中下游地区是我国稻麦主产区,辨析该区农业生产过程的环境效应,可为实现农业绿色发展提供理论指导。以稻麦轮作典型生产区江苏南京为例,应用生命周期评价方法对该系统生命周期的资源消耗和污染物排放清单进行分析和评价。结果表明:在该稻-麦轮作体系中,水稻生命周期的环境影响主要是富营养化、水体毒性、环境酸化和土壤毒性,环境影响指数分别为2.32、0.76、0.33和0.27;而小麦生命周期的环境影响主要为富营养化、水体毒性、土壤毒性和环境酸化,环境影响指数分别为2.50、2.09、0.32和0.23。肥料、农药、柴油的生产和使用是引起能源消耗和气候变暖的主要因素;农户超量施用氮肥是造成潜在环境酸化和富营养化的关键;农药的使用是造成水体毒素和土壤毒素的最主要原因;而氮肥和农药投入对人类毒性均有较大影响。因此,在工业领域加快新型能源开发,实施清洁生产;在农业领域优化田间管理措施(如减少氮肥施用、研发多功能一体化农机及推广低毒高效农药)能有效控制长江中下游地区稻麦生产负面环境影响,提高该区农业可持续发展能力。  相似文献   

13.
Life cycle assessment part 2: current impact assessment practice   总被引:26,自引:0,他引:26  
Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse, recycling, through to ultimate disposal. These all contribute to impacts such as climate change, stratospheric ozone depletion, photooxidant formation (smog), eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources and noise-among others. The need exists to address these product-related contributions more holistically and in an integrated manner, providing complimentary insights to those of regulatory/process-oriented methodologies. A previous article (Part 1, Rebitzer et al., 2004) outlined how to define and model a product's life cycle in current practice, as well as the methods and tools that are available for compiling the associated waste, emissions and resource consumption data into a life cycle inventory. This article highlights how practitioners and researchers from many domains have come together to provide indicators for the different impacts attributable to products in the life cycle impact assessment (LCIA) phase of life cycle assessment (LCA).  相似文献   

14.
张家口坝上地区环境与经济协调发展浅析   总被引:4,自引:0,他引:4  
张家口坝上地区自然条件较差,是河北省及全国范围内经济发展为落后的地区,,发展经济与改善环境是本区所面临的两大难题。本文对其经济与环境间的相互影响进行了分析,并以可持续发展为理论基础,提出了开发水资源,发展灌溉农业,实现粮食稳定自给和退耕还牧,改善生态环境的发展对策。  相似文献   

15.
农业面源是造成太湖富营养化的重要污染源。通过对太湖西岸重点保护区内农民进行随机入户调查,系统地研究了当地农民在水稻种植中的施肥行为特征及其主要影响因素。研究结果表明:(1)在普遍过度施用氮肥的背景下,个体农户在施肥量和施肥种类上存在显著差异;(2)农户施肥行为普遍具有主观性和盲目性的特征。农民的年龄阶段和其对控制化肥用量的态度对氮肥施用量具有显著性影响;(3)在分析化肥施用态度和环境意识对施肥量的影响中,出现了一些与预期相反的趋势。这进一步显示了当地农民在施肥方面缺乏科学引导,导致部分农民尽管存在着良好的控制化肥施用的意愿,却不知如何有效实施。因此,针对当地农民年龄大、文化低等普遍特征,有针对性地设计一些不用复杂模型和流程的简单施肥改善项目,并辅以参与激励措施与风险保障措施,在降低当地氮肥施用量和流失量方面具有巨大潜力,并对太湖流域的水污染控制起到事半功倍的效果  相似文献   

16.
三峡库区消落带农用坡地氮素流失特征及其环境效应   总被引:1,自引:0,他引:1  
三峡库区消落带坡地的自发农用较为常见,消落带的这种利用方式可能加剧养分流失并对库区水环境造成影响.通过对库区2011~2013年3个落干期消落带农用坡地的地表径流、壤中流中氮素形态与浓度进行定位监测,研究消落带农用坡地氮素流失特征及其环境效应.结果表明:常规施肥下,消落带农用坡地侵蚀模数为1 443 kg/(hm2·a),落干期内坡地平均径流量为230 mm,径流系数为0.58,其中壤中流流量占总径流量的77%.历次降雨产流事件中常规施肥处理时,地表径流、壤中流中TN平均浓度分别是4.85±0.85、20.73±2.05 mg/L,落干期地表径流(泥沙)和壤中流的TN流失量分别为6.63± 1.19、35.22±3.38 kg/hm2,分别占当季施肥量的2.2%、11.7%.可见,随壤中流流失是三峡库区消落带农用坡地氮素流失的主要途径.与常规施肥处理相比,减量施肥处理使地表径流(泥沙)、壤中流TN流失通量分别显著降低了25%、48%,表明减少氮肥用量可以显著降低消落带农用带来的环境风险,建议消落带农用地氮肥进行减量施肥,使其既不影响作物产量,也显著降低氮流失.  相似文献   

17.
The beginning of the twenty-first century saw a surge in the growth of construction industry, particularly the housing sector in India. This led to the growing demand of ceramic tiles. This growth is responsible for large-scale consumption of natural resources and generation of solid waste. The objective of this paper is to assess the environmental impact of vitrified ceramic floor tile supply chain by performing life cycle assessment (LCA) following international standards of ISO 14040 series guidelines. The impact has been determined by conducting a LCA using Umberto NXT software (eco-invent 3.0 database) with ReCiPe endpoint and midpoint methods. It has been found that the manufacturing stage of supply chain is generating highest impact on environment in all the categories. Impact analysis of different input resources/material shows that red oxide used in glaze preparation, electricity in manufacturing, packaging material, distribution by trucks, installation of tiles using concrete and disposal of packaging material are responsible for most of the environmental impact. This study will offer the essential quantitative assessment to recognise the phases and materials which are highly responsible for the degradation of environment so that appropriate interventions by the different stakeholders can be planed.  相似文献   

18.
South Africa, a main food exporter in SADC, is characterised by a dual agricultural economy consisting of a well-developed commercial sector and smallholder, often subsistence, farming. Using the Ricardian cross-sectional framework, we examine the impact of climate change on a nationwide sample of crop, horticulture, livestock and mixed commercial farming systems. We find that a simultaneous decrease in precipitation and an increase in temperature will reduce productivity; and that an increase in temperature alone negatively affects farm output more than a decrease in precipitation. One of the most robust findings is the difference in the extent to which different commercial production systems will be impacted. That is, the results indicate that the strongest impact will be amongst specialised commercial crop farming system. In contrast, mixed farming systems appear to be the least vulnerable. This finding is consistent with studies on small-holder farms in sub-Saharan Africa. Hence, it appears that despite the likely benefits derived from economies of scale, commercial farms are, somewhat, equally vulnerable to climate change. Further, a province-wise assessment revealed that areas that already face disadvantageous climatic conditions will become even less productive. Overall, the findings suggest that practicing mixed farming methods will strengthen the resilience of commercial farms to climate change and that access to extensions—insurance and irrigation—is likely to reduce the risks.  相似文献   

19.
Understanding crop responses to climate is essential to cope with anticipated changes in temperature and precipitation. We investigated the climate–crop yield relationship and the impact of historical climate on yields of rice, maize and wheat in the Koshi basin of Nepal. The results show significant impact of growing season temperature and precipitation on crop production in the region. Rice, maize and wheat cultivated at altitudes below 1,100, 1,350 and 1,700 m amsl (above mean sea level), respectively, suffer from stress due to higher temperatures particularly during flowering and yield formation stages. Responses of crop yields to a unitary increment in growing season mean temperature vary from ?6 to 16 %, ?4 to 11 % and ?12 to 3 % for rice, maize and wheat, respectively, depending on the location and elevation in the basin. In most parts of the basin, we observe warming trends in growing season mean temperatures of rice, maize and wheat over the last few decades with clear evidence of negative impacts on yields. However, at some high-elevation areas, positive impacts of warming are also observed on rice and maize yields. If the observed trends in temperature continue in future, the impact is likely to be mostly negative on crop production in the basin. However, crop production may gain from the warming at relatively higher altitudes provided other conditions, e.g., water availability, soil fertility, are favorable.  相似文献   

20.
The environmental impacts of moving to different traction power sources have not been well studied in either developing countries or modern agriculture. This study assesses the environmental impact of the transition from animal to tractor power and vice versa. Three different scenarios are analyzed: a developing country context where draught animal power (DAP) is actually in use; a similar context where DAP is replaced by mechanical traction; and a developed country scenario where mechanical traction is replaced by DAP. The impact assessment focuses on global warming (GW) and primary energy consumption (PEC). The DAP system refers to an Indonesian case study where Peranakan Ongole cattle are used for work, together with the production of milk and meat, and fed with two forage-supplying alternatives. The mechanical traction system considers the cases of a two-wheel tractor (2WT) and a rear-wheel-drive tractor (4WT). In the first scenario, assessing DAP impacts for plowing through process subdivision and indirect impacts allocation to co-products, DAP has a consistent advantage regarding energy consumption, while for CO2eq emissions, performance is better only in the case of 2WT. In the second scenario, considering product equivalent systems, substituting DAP with tractor power and maintaining the same DAP livestock farming more than doubles the impact; only with the introduction of modern, specialized livestock farming is a reduction achieved. In the third scenario, replacing mechanical traction with DAP results in a greater than three-fold increase in impact for PEC and more than 17 times increase for GW. Further work on the influence of system definition and the socio-economic background would improve the estimates produced in this study.  相似文献   

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