首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
基于欧氏距离的农业可持续发展评价理论构建与实例验证   总被引:10,自引:0,他引:10  
杨世琦 《生态学报》2017,37(11):3840-3848
基于欧氏距离构建了农业可持续发展评价理论体系,包括农业可持续发展模型、评价函数、评价等级、目标系统、零系统与评价指标框架。选取宁夏吴忠市2000—2012年数据开展了实例验证,可持续发展指数(ASDI)范围是[0.65,0.70],呈现平缓上升趋势,呈现中持续发展状态。评价结果基本反映了农业系统情况,表明基于欧氏距离构建农业可持续发展评价方法是可行的。该方法的创新性与优势表现在:一是具有可靠的方法论;二是构建了农业可持续发展模型,引入目标系统与零系统概念,建立了农业可持续发展评价参照系,提升了评价的可控性;三是数学函数中隐含了指标权重,回避专家打分法引起的误差或错误,也回避了由于指标增减中指标权重不得不重新赋值的专家打分法缺陷;四是可持续发展评价指数采用函数模型转换,把欧氏距离转换成百分数值一方面易理解,另一方面不同系统的指数值能够进行相互比较。宁夏吴忠农业可持续发展水平偏低的主要原因是氮肥施用量高、秸秆还田率低、复合肥或专用肥比例低、保护性农作技术推广不够、土壤有机质低以及农村人均收入偏低等。  相似文献   

2.
江苏省区域农业生态经济的时空变异分析   总被引:1,自引:0,他引:1  
唐婷  李超  张雷  吕坤  周治国 《生态学报》2014,34(14):4025-4036
以江苏省徐连、沿海、宁镇扬、沿江和太湖5个经济区及其9个代表县市区域为研究对象,基于"社会-生态-经济"的系统分析,建立了包括目标层、准则层和指标层3个层次多指标的农业生态经济综合评价指标体系,采用主成分分析方法对评价指标体系进行检验、筛选,并以江苏省为案例,综合分析了农业生态经济系统的时空变异特征。结果表明:江苏省农业生态经济发展水平的时空变异明显,空间上,徐连、沿海、宁镇扬、沿江和太湖5个经济区表现出由北向南逐渐上升的趋势,且随时间的推移逐渐上升;时间上,徐连和太湖经济区农业生态经济发展水平在1999—2008年间呈持续上升,处于良好或优质协调状态。虽然两经济区的农业生态环境-经济发展协调发展水平均较高,但差距较大,徐连和太湖经济区的农业生态环境-经济发展协调度从1999年到2008年呈逐渐下降趋势,但总体上仍处于良好或优质协调状态。  相似文献   

3.
Engineering research and development contributes to the advance of sustainable agriculture both through innovative methods to manage and control processes, and through quantitative understanding of the operation of practical agricultural systems using decision models. This paper describes how an engineering approach, drawing on mathematical models of systems and processes, contributes new methods that support decision making at all levels from strategy and planning to tactics and real-time control. The ability to describe the system or process by a simple and robust mathematical model is critical, and the outputs range from guidance to policy makers on strategic decisions relating to land use, through intelligent decision support to farmers and on to real-time engineering control of specific processes. Precision in decision making leads to decreased use of inputs, less environmental emissions and enhanced profitability-all essential to sustainable systems.  相似文献   

4.
肖明  董楠  吕新 《生态学杂志》2015,26(8):2571-2580
可持续农业概念提出30多年,世界各地区都有不同的认识.我国类似的概念被称作生态农业,历经几十年的实践,在理论、模式及配套技术上都有了认识总结,但迄今仍然缺乏明确界定的应用指导.欧盟提出的有机农业模式现在被广为接受,但其受益群体和承担的社会责任、生态责任均有一定的局限性.针对以上问题,本文从生态学角度出发,分析了生态失衡弊端对农产品质量安全的负面影响,提出了可持续安全农产品概念.支持该概念的农业生产模式追求两方面的价值,一是拥有一个健康的生态圈环境作为农业产业平台,二是能从这个产业平台可持续地获取安全农产品.围绕该概念的核心价值,设计了生产可持续安全农产品的农业构建模式,同时提出了对不可逆、不可控、难修复的农艺措施在改良之前放弃使用的原则.最后通过与有机农业在承担责任、受益群体、农艺措施选用以及对转基因技术的认识等方面进行对比,反证可持续安全农业模式下生产的农产品在数量安全、质量安全上的先进性.  相似文献   

5.
The control of heavy metals in such a way that soil functioning and product quality are not impeded is a prerequisie to sustainable agricutture. The current status of heavy metal accumulation in agricultural soils differs widely by region, by metal, and by agricultural system; levels of concern have already been reached in several regions (for instance, in the Netherlands and Australia). An analysis of the input and output fluxes of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in agriculture and of their resulting accumulation in agricultural soils is necessary to define strategies that ensure sustainable management of these metals in agricultural systems. In this article, general aspects of heavy-metal balance studies are described for the agricultural sector within the broader context of substance flow analysis and industrial ecology. The approach chosen in this study is both precautionary and related to actual problem areas.  相似文献   

6.
利用农业生物多样性持续控制有害生物   总被引:6,自引:0,他引:6  
高东  何霞红  朱书生 《生态学报》2011,31(24):7617-7624
农业生物多样性对保障全球粮食安全和农业可持续发展至关重要.人类在多样性的形成上发挥了关键作用,人类结合自然进化创造了遗传多样性、物种多样性和生态系统多样性.农业生物多样性发挥了很多社会经济和环境功能:保障粮食安全;维持农业生态系统可持续发展;赋予农村经济适变性.但当前人类毁灭农业生物多样性的速度更为惊人.在总结石油农业单一化种植的生态负效应、传统农业提倡“天人合一”的生态正效应的基础上,分析讨论了利用农业生物多样性持续控制有害生物的必要性和可行性,从生态系统多样性、物种多样性和种内遗传多样性3个层次,归纳了构建和恢复农田生物多样性的基本方法.基于病理学、生态学、营养学和生理学等学科领域,从群体异质效应、稀释效应、微生态效应、诱导抗性效应、物理阻隔效应、生理学效应和化感效应等7个方面,归纳了利用农业生物多样性持续控制有害生物的基础原理.寻求低投入、高效益、多样化和可持续的农业生产系统是当今世界许多科学家、决策者和生产者共同关心的问题.农业生物多样性具有重要的生态作用,在现代农业框架下,是合情合理构建持续、稳定、健康、高产的农田生态系统,持续控制有害生物的金钥匙.为此必须加强四方面的课题研究:各种作物之间的相生相克关系及其作用机理;各种有害生物的主要天敌种类、生物学、生态学特性及其适生环境;利用农业生物多样性全面、持续控制有害生物的农业生产模式;与其相配套的农艺措施与农业机械.  相似文献   

7.
试论东北地区农业节水与农业水资源可持续利用   总被引:7,自引:0,他引:7  
刘作新 《应用生态学报》2004,15(10):1737-1742
针对振兴东北老工业基地大背景下的东北地区水资源紧缺状况,通过对农业水资源和农业节水潜力的系统分析,提出了东北地区的系统农业节水战略.根据东北地区农业生产特点和农业发展需求,进行节水农业分区,确定不同农业类型区节水高效栽培模式与关键集成技术体系.论述了东北地区农业水资源可持续利用系统学方略和实施系统节水治水工程的必要性,以及农业节水研究的发展趋势.  相似文献   

8.
广西灵川县种植业的可持续发展   总被引:1,自引:0,他引:1  
广西是我国南方农业大省(区),明确其农业发展的制约因素,提出具体的解决措施,实现农业可持续发展,对解决农业、农村和农民问题,促进经济持续、快速、健康发展,实现社会主义现代化建设战略目标具有重要的理论和现实意义。主要采用了参与性农户评估方法(PRA),通过随机入户方式,与农户面对面交流,并结合调查问卷,对广西桂林市灵川县11个乡镇的农户进行了调查访问,为方便研究和数据处理,在数据分析过程中将该县11个乡镇分为3个片区:东部片区、中部片区、北部片区,对比3组农户的文化素质、种植制度、冬季农业现状、农业需求和农田水利设施等方面问题,探讨广西农业可持续发展的制约因素,并提出相应的对策,以期为广西农业可持续发展提供理论依据。调查结果表明,虽然目前灵川县农业取得众多发展成就,但仍存在以下几个方面的问题,严重影响了该县种植业可持续发展的进程。一是种植制度结构单一,二是冬季农业发展薄弱,三是种植技术贫乏,四是基础设施建设不完善等,因此,为促进灵川县种植业可持续发展,亟需采取以下对策和措施:调整作物种植结构,建立合理的种植制度;大力发展冬季农业;满足农民最迫切的农业需求;加强农业基础设施建设等。  相似文献   

9.
Sustainability would never be achieved farewell as agricultural practices continue beyond the carrying capacity of the ecosystem through the exaggerated abuse of agricultural chemicals. The rapid growth of agricultural productivity in chemical farming systems is shrinking off. Moreover, environmental torrent from agricultural activities jeopardizes agricultural growth in several countries. Problems associated with the wealthy agricultural production in the developed world and underproduction in developing countries necessitate a widely accepted assessment of the present status of agriculture. It is time to install new farming systems committed to following environmental and sustainable approaches, and producing healthy food free from agrochemical residues. Ecologically oriented farming routines are being developed within the frame of the recent achievements in environmental biotechnology, the most important of which is the clean farming system which is increasingly acknowledged as a potential solution to copious problems overlaying present world agriculture. It is a farming system, which aims at evading the routine use of agricultural chemicals and reducing their rates of application. Clean farming systems directly give rise to four environmental biotechnologies, i.e., recycling of composted organic waste, fortifying the rhizosphere soil with biofertilizers, encouraging the use of biopesticides in agricultural practices and bioremediation of polluted agro‐ecosystems.  相似文献   

10.
Agroecosystems have traditionally been considered incompatible with biological conservation goals, and often been excluded from spatial conservation prioritization strategies. The consequences for the representativeness of identified priority areas have been little explored. Here, we evaluate these for biodiversity and carbon storage representation when agricultural land areas are excluded from a spatial prioritization strategy for South America. Comparing different prioritization approaches, we also assess how the spatial overlap of priority areas changes. The exclusion of agricultural lands was detrimental to biodiversity representation, indicating that priority areas for agricultural production overlap with areas of relatively high occurrence of species. By contrast, exclusion of agricultural lands benefits representation of carbon storage within priority areas, as lands of high value for agriculture and carbon storage overlap little. When agricultural lands were included and equally weighted with biodiversity and carbon storage, a balanced representation resulted. Our findings suggest that with appropriate management, South American agroecosystems can significantly contribute to biodiversity conservation.  相似文献   

11.
The dike-pond system was a form of ecological engineering that was a component of successional dikes and ponds along the banks of the Pengxi River in the drawdown zone (DDZ) of the Three Gorges Reservoir (TGR). The application of science-based evaluation system was appropriate for the flows of emergy in this agricultural ecosystem. The Emergy Analysis (EmA) has the ability to transform different types of inputs to a common form to allow meaningful comparisons across different systems. This study made use of the emergy analysis that assessed two different types of farming methods in the DDZ of the TGR. One method was planning crops in a dike-pond system (model I), and the other method was conventional agriculture (model II). In addition, the Exergies of both yields of agriculture methods were calculated, and the Exergy and Emergy Density (ED) were combined to explore the quality of these methods. The results showed that the two models relied on different resources. The ED yield of both models were similar, but the emergy investment of model II was greater than that of model I. Model II also used less renewable energy input to the agricultural systems than model I. The agricultural emergy sustainability index (AESI) of model I system (AESI = 2.4 > 1) was greater than that of model II system (AESI = 0.5 < 1), which indicated that the sustainable development of model I was stronger than that of model II in the DDZ of the TGR. The ratio Exergy/Emergy density (Rex/em) in the two models of different agricultural system were 121.52 × 10−3 J/sej (Model I) and 24.19 × 10−3 J/sej (model II). Model I was greater than model II, and the result intimated that the model I agricultural system was a new method in the DDZ, but it was older and closer to the steady state than model II. The Emergy and Exergy analysis certifies that model I has a more acceptable and more sustainable development potential and is more stabilized in the DDZ of the TGR.  相似文献   

12.
Non-governmental organizations have proposed nine different global prioritization schemes, some of them focusing on areas with low vulnerability (a proactive reasoning) and some others targeting areas with high vulnerability (a reactive reasoning). The main threat to the remaining natural habitats of these areas is the expansion of agriculture. We evaluated the spatial congruence between agricultural land cover and global conservation priority areas in the present and in the future using a spatial model of land use cover change from 2000 to 2100. We showed that by the year 2000, the extent of agriculture was larger in reactive priority areas than in the rest of the world, while it was smaller in areas highlighted as important under proactive approaches. During the twenty-first century, we found a general increase in agriculture area and the difference between the approaches of conservation schemes is expected to hold true, although we found that high-biodiversity wilderness areas (HBWA), a proactive scheme, may be specially affected in certain scenarios of future change. These results suggest an increase in conservation conflicts over this century. In face of agricultural expansion, both kinds of prioritization approaches are important, but different strategies of protection are necessary (e.g., reactive approaches need the urgent protection of remnant habitats, while proactive ones have space to create megareserves). Further, conservation organizations must include agriculture expansion data and their uncertainty in conservation planning in order to be more successful in biological conservation.  相似文献   

13.
王勇  章家恩 《生态科学》2007,26(3):274-280
经济社会发达地区普遍是以城市为中心的,可持续发展面临着严重的资源环境压力。发达地区的农业比重较低,发展空间萎缩,受环境污染的影响大,自身发展也存在诸多问题。但发达地区非常需要保留农业的适度发展,因为农业具有不可替代的生态服务功能,对城市可持续发展有强大的推动作用。保持发达地区农业可持续发展的策略是维持农业生态系统的健康,以及采取科学的、生态的农业环境和资源管理的技术手段。  相似文献   

14.
This study aimed to enhance land use and land cover (LULC) change models by addressing their main limitations, which include the lack of accountability and temporal stability of driving forces. Additionally, the study aimed to create area-based scenarios to forecast future LULCs, rather than solely relying on distribution-based scenarios. To accomplish this goal, the study developed a coupled System Dynamics (SD) and Cellular Automata (CA) modeling system to simulate possible LULC changes in the Gavkhooni Basin, central Iran. The study utilized LULC maps from Landsat images in 2001, 2011, and 2021 to analyze spatio-temporal land use changes in the region. Agricultural and residential transition suitability layers were produced using a spatial Multi-Criteria Evaluation procedure and applied to inform the CA model in the proper allocation of LULC changes. Three interconnected water supply, agricultural, and residential area projection subsystems were developed using system dynamics method to determine land requirements for LULC conversions from 2020 to 2041, taking into account factors such as water availability, land suitability, agricultural labor force, and economic development. Ten scenarios were developed based on changes in the key variables affecting the limiting factors, such as climatic conditions and water management policies, to project agricultural and residential areas in the future. The CA's spatial allocation informed by transition suitability layers was found to be satisfactory with a Kappa-location value of 0.85. The subsystems were competent in projecting water supply with Mean Absolute Error (MAE) values of 6.57% and the dynamics of agricultural and residential areas with MAE values of 2.94%, whereas those of the Markovian Chain model were found to be 23.02% and 7.5% for agricultural and residential areas, respectively. The study found that available agricultural areas varied significantly between 86.53 and 1480 sq.km under different climatic conditions, irrigation efficiency, and agricultural water assignment coefficients between 2024 and 2033. Residential area demand was found to be increasing with different rates under the scenarios between 47.40 and 73.01 sq.km. The SD-CA coupled framework presented in this research can be viewed as a decision support system to develop compensatory strategies for better management and planning of agricultural and residential lands.  相似文献   

15.
农业生命周期评价研究进展   总被引:1,自引:0,他引:1  
作为评价产品系统全链条环境影响的有效工具,生命周期评价(LCA)方法已广泛用于工业领域。农业领域也面临着高强度的资源和环境压力,LCA在农业领域的应用应运而生。旨在综述已有农业LCA研究的基础上,鉴别农业LCA应用存在的问题,并为农业LCA未来的发展提出建议。目前农业LCA存在系统边界和功能单位界定不明晰、缺少区域清单数据库、生命周期环境影响评价模型(LCIA)不能准确反映农业系统环境影响、结果解释存在误区等方面的问题。为了科学准确地衡量农业系统的环境影响,促进农业系统的可持续发展,文章认为农业LCA应该从以下几个方面加强研究,即科学界定评价的参照系、系统边界的扩大及功能单位的合理选取、区域异质性数据库构建与LCIA模型开发、基于组织农业LCA的开发以及对于利益相关者行为的研究。  相似文献   

16.
薛智超  甄霖  闫慧敏 《生态学报》2023,43(15):6081-6098
黄土高原丘陵沟壑区生态环境脆弱,近几十年生态保护工程的实施带来显著的生态恢复效果,也对农户的生计策略与区域粮食安全产生了影响。刻画生态脆弱区人-地系统复杂响应过程,可以为区域可持续的土地利用管理模式提供依据。研究从土地多功能出发,着眼于黄土丘陵沟壑区河谷川地、梁峁区域、黄土塬地、土石山地以及城郊区域等不同的典型地貌类型与代表区域,采用多层次利益相关者参与式的评估框架,以农户的耕地利用行为及生态工程影响与未来发展为切入点,设置惯性发展情景、发展优先兼顾生态情景、农业优先兼顾生态情景以及生态优先兼顾发展情景,构建多智能体模型对区域土地利用与土地多功能的时空变化开展模拟。主要结果表明:(1)生态优先兼顾发展情景综合影响最高且对各维度影响相对均衡,而农业优先兼顾生态情景对区域土地的经济维度的功能和社会维度具有更为明显的提升效应;(2)根据土地多功能空间变化模拟结果,区域土地利用破碎化明显且耕地的撂荒对全域土地多功能均表现出明显的限制作用,农业优先兼顾生态情景中土地功能发生下降的面积最少;(3)发生土地功能下降的区域主要分布在土地质量较差、坡度处于5—15°范围内、地形起伏度较大以及距离道路较远...  相似文献   

17.
Most of the world's biodiversity will continue to exist outside protected areas and there are also managed lands within many protected areas. In the assessment of millennium targets, there is therefore a need for indicators to measure biodiversity and suitability of habitats for biodiversity both across the whole landscape/seascape and in specific managed habitats. The two predominant land uses in many inhabited areas are forestry and agriculture and these are examined. Many national-level criteria and indicator systems already exist that attempt to assess biodiversity in forests and the impacts of forest management, but there is generally less experience in measuring these values in agricultural landscapes. Existing systems are reviewed, both for their usefulness in providing indicators and to assess the extent to which they have been applied. This preliminary gap analysis is used in the development of a set of indicators suitable for measuring progress towards the conservation of biodiversity in managed forests and agriculture. The paper concludes with a draft set of indicators for discussion, with suggestions including proportion of land under sustainable management, amount of produce from such land, area of natural or high quality semi-natural land within landscapes under sustainable management and key indicator species.  相似文献   

18.
In the development of strategies for countermeasures aimed at the rehabilitation of contaminated areas, essential is to identify criteria for assessing their effectiveness and factors influencing the priority of the criteria chosen. A method is suggested for assessing effectiveness of countermeasures in agriculture based on a multicriterium analysis of radiologic, economic, regulatory and socio-psychological indicators characterizing the use of countermeasures. Rating of countermeasures strategies is presented depending on financing of works on the rehabilitation of the Chernobyl affected areas.  相似文献   

19.
《农业工程》2020,40(5):347-352
Ecological studies have been focused on large, rare or endangered species but species which are adapted to traditional agroecosystems or rural environments received less attention. For example, Little owl is a typical inhabitant of agricultural lands and its population had greatly reduced due to the mechanized agriculture. In this paper, we built the first country level habitat suitability map for the little owl and identified the most influential environmental predictor of its distribution in Iran. We used species presence data (177 distribution points) and eight uncorrelated environmental variables to model the species suitable habitats using the maximum entropy approach (Maxent). Results showed that suitable habitats for this species are located in the northwest, parts of north east and southwest of Iran. Distance to forests, distance to human settlements and distance to agricultural lands are the most important determinants of the little owl distribution in Iran. Human migrations from rural areas to the cities and availability of many vacant human settlements surrounded by traditional and semi-modern agricultural landscapes produce suitable habitats for little owl in Iran.  相似文献   

20.
土壤生物与可持续农业研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
农业的可持续发展是人类文明持续繁荣的重要保障。从原始农业到工业化农业的发展历程,是"自然力"不断削弱,"人为调控力"不断加强的过程。新兴的可持续农业,则希望将人为调控和自然过程协调融合,建立近自然的高效的现代农业体系。但是,面对土壤生物极高的多样性、生物和非生物过程的复杂互作及其高度的时空异质性,基于还原论的传统科学研究方法探究地下生态系统的"自然过程"困难重重。人为管理措施对农田生态过程调控的针对性和调控效果受到极大限制。尽管如此,土壤生物在生态系统服务中的作用已在世界范围内得到空前重视。如何充分发挥土壤生物在可持续农业中的作用,已成为现代农业研究领域的重要突破口。简述了土壤生物与可持续农业研究的学科发展历史,总结了农业管理措施对土壤生物及土壤食物网特征的影响,突出了土壤生物群落在可持续农业模式中土壤结构改善、土壤肥力提高和化肥农药减施等方面的积极作用;最后探讨了当前的研究难点和未来的研究方向,并对如何充分发挥土壤生物在现代农业中的贡献进行了初步的思考。认为:土壤有机质,土壤结构和土壤食物网以及三者的内在联系是可持续农业研究的关键。土壤有机质管理是调控土壤结构、土壤食物网及生态系统生产力的重要支点,但也是可持续农业模式不确定性的重要来源。基于同位素示踪等整体性分析方法,开展典型农田生态系统土壤食物网特征及其生态功能的系统研究,揭示农业模式、土壤食物网特征及生态系统生产力的关键联系,是充分发挥土壤生物在可持续农业中的积极作用的基础。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号