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1.
本文概述了吉林省东部长白山区农业气候资源的立体变化规律,分析了如何根据立体气候规律安排农作物品种的垂直布局,确定主要特产植物适宜裁培高度、森林植被类型和立体农业生态经济系统建设等问题,指出了充分利用气候资源搞好山区农业立体开发的有效途径。  相似文献   

2.
赵丰  聂晶川 《新疆环境保护》1993,15(3):28-29,36
根据新疆地区干旱、荒漠和具有绿洲生态系统的特点,提出了建设新疆绿洲立体农业的几个重要方面:保护和扩大绿洲;农、林、牧、草综合立体发展;大力发展种植业;推广庭院经济;合理投入等。  相似文献   

3.
大渡河干热河谷光、热资源充裕,雨、热同期,主、支流(沟)纵横交错,为农业灌溉提供了水源;经济林木资源优势相对突出,农业环境资源立体层次丰富。因此,本文提出了开发大渡河干热河谷农业环境资源的4种模式。  相似文献   

4.
通过镇江市在开展生态循环农业实践中形成的以沼气为纽带的资源利用、立体种养结合、节约型绿色农产品生产、秸秆综合利用、生态观光农业及种养加结合、农工贸一体化等6种发展模式,分析了发展生态循环农业中存在的主要问题,提出了发展生态循环农业的对策和建议,为各地发展生态循环农业提供参考。  相似文献   

5.
该文就常熟市农业资源的实际出发,从改造中低产田、开发长江滩地、复耕零星废弃地、利用庭园空间、立体利用水面、开发杂草资源、加工植物蛋白饲料及发展棉田套作等8个方面的途径,评价了农业开发潜力,说明在经济发达地区的农业开发是大有可为的。文章提出了相应的实施对策。  相似文献   

6.
建设生态农业 发展立体种植   总被引:2,自引:0,他引:2  
生态农业是按照生态经济规律建立起来的可持续发展的农业,立体种植,养殖,种养是生态农业向现代化集约经营发展的一种重要形式,新疆发展立体生态农业大有作为。  相似文献   

7.
阐述了人类不合理的农事活动所引发的6类农业环境地质问题——水资源匮乏及水资源污染、土壤污染、土壤侵蚀、土地沙化、土地盐碱化、土地非农业利用及农业地质灾害。综合治理农业环境地质问题是一项长期行为,必须建立在法制的基础上,因地制宜、合理布局、合理开发利用农业资源,使农业生产走上可持续发展的道路。  相似文献   

8.
本文运用现代集约持续农业观点,从分析青海省农业现状着手,以综合解决食物自给和持续发展为目标,对全小农业四个子系统及农业四个部门子系统进行了系统分析,从而提出了青海省发展种植业、畜牧业、水产业、林业的一些思路。  相似文献   

9.
发展无公害农业的几点思考   总被引:1,自引:0,他引:1  
“国以农为本,民以食为天”,农业是国民经济的立足之本,保护农业生态环境,发展无公害农业是一项功在当代,利在千秋的大事。我国在保护农业生态、控制污染方面已做了大量工作,取得了一定成效。同时,我们也应该认识到我国作为一个发展中国家,既有历史遗留下来的大量问题,又有经济发展过程中涌现的新矛盾、新问题。人多地少.土地负载沉重,农业生态系统的破坏较为严重,我国年均工业排污300多亿吨,废气4亿多立方米,废渣5亿吨,80%的废水未经处理就进入农田生态环境。由于农业措施本身所造成的污染十分严重,目前我国受农药污染的…  相似文献   

10.
四川省农业环境影响及发展循环经济模式初探   总被引:1,自引:0,他引:1  
曾晓兰 《四川环境》2009,28(3):114-119
四川省是农业大省,农业可持续发展对其经济发展具有重要意义,四川省的农业对环境的影响源于种植业和养殖业两方面。针对四川省农业的特点,本文提出四川省发展农业循环经济模式的思路及对策。  相似文献   

11.
选取2013—2016年粤港澳大湾区11市大气主要污染物数据,采用社会网络分析法(SNA)对粤港澳大湾区大气污染的空间关联性进行实证研究。结果发现:①大湾区城际大气主要污染物的空间关联均呈现出较典型的网络结构特征。②城际大气污染存在明显的空间关联和空间溢出,各城市空间联系越来越密切。③大湾区大气污染空间网络具有稳定性特征,PM2.5和SO2的空间溢出得到有效控制,而PM10和NO2的空间溢出具有长期稳定性。④珠海、佛山、惠州、中山在大湾区城际大气污染空间关联网络中处于中心地位。⑤各城市在大气污染空间网络中存在明显的非均衡地位。  相似文献   

12.
Abstract: The spatial variability of the data used in models includes the spatial discretization of the system into subsystems, the data resolution, and the spatial distribution of hydrologic features and parameters. In this study, we investigate the effect of the spatial distribution of land use, soil type, and precipitation on the simulated flows at the outlet of “small watersheds” (i.e., watersheds with times of concentration shorter than the model computational time step). The Soil and Water Assessment Tool model was used to estimate runoff and hydrographs. Different representations of the spatial data resulted in comparable model performances and even the use of uniform land use and soil type maps, instead of spatially distributed, was not noticeable. It was found that, although spatially distributed data help understand the characteristics of the watershed and provide valuable information to distributed hydrologic models, when the watershed is small, realistic representations of the spatial data do not necessarily improve the model performance. The results obtained from this study provide insights on the relevance of taking into account the spatial distribution of land use, soil type, and precipitation when modeling small watersheds.  相似文献   

13.
本文引入资源和环境因素,以城镇化综合指数为期望产出,运用SBM方向性距离函数测算了2010-2020年长江经济带112个地级市(州)的绿色城镇化效率,并采用空间面板模型和地理探测器对绿色城镇化效率的影响因素进行实证分析。结果表明:长江经济带绿色城镇化效率整体水平不高,下游地区绿色城镇化效率高于上游和中游地区,资源消耗和环境污染是效率损失的主要来源;绿色城镇化效率表现出较为明显的热点-次热点-次冷点-冷点自东向西的带状分布格局,存在显著的空间正相关性。政府财政支出对绿色城镇化效率产生负向影响,外商直接投资和产业结构对提升绿色城镇化效率有显著的促进作用,且三者的影响具有地区差异性;市场力因素有利于绿色城镇化效率的提高。邻近城市间绿色城镇化效率的空间溢出效应明显,且空间溢出效应是长江经济带绿色城镇化效率空间差异的最主要因素,各因素的影响具有协同增强的作用。  相似文献   

14.
通过对1960-2005年新疆54个气象站的气象资料进行分析,研究了新疆不同强度等级沙尘暴天气的时空分布年际演变趋势.结果显示:新疆各强度等级沙尘暴天气的发生区域均在逐年缩小,强沙尘暴、扬沙发生区域有东移的趋势,浮尘空间分布格局显现出向南退缩的趋势.沙尘暴空间格局变动较频繁没有明显的移动趋势.  相似文献   

15.
Site-specific phosphorus management is done to optimize crop production and minimize P loss from soils. The spatial variability of the available P prior to fertilizer application and the P-fixation tendency of soil both need to be taken into account for variable-rate P application. The objectives of this research were to document the spatial variability of the fertilizer-P availability index, which shows the P-fixation tendency, and to develop a strategy that takes the spatial distribution of this index into account for site-specific phosphorus application. In this study, the spatial patterns of the fertilizer-P availability index were characterized by using geostatistics. The ordinary kriging was used for spatial interpolation of the fertilizer-P availability index. Because the fertilizer-P availability index of soil is related to oxalate-extractable Fe and Al and because measuring oxalate-extractable Fe and Al is much easier than directly determining the fertilizer-P availability index, the spatial distribution of the fertilizer-P availability index can be obtained using the oxalate-extractable Fe and Al data. The spatial distribution of Olsen-extractable P, which was used to measure the available-P status prior to fertilizer-P application, was also estimated by using ordinary kriging. The required fertilizer-P amounts were then determined using the kriging estimates of the fertilizer-P availability index and Olsen-extractable P. A fertilizer-P recommendation map for the 430-ha study site in Changhua county, Taiwan was generated by using this approach for illustration. The proposed method for generating fertilizer-P recommendation maps can be used for variable-rate application to maintain an adequate P status for crop production and to potentially reduce the P loss from soils.  相似文献   

16.
引入变异系数和相关性分析,结合入境游客的群体特征与时空差异,详细分析了旅陕入境旅游流与三大口岸的空间差异及关联度大小。研究表明,入陕外国人、港澳台游客流和三大口岸入境旅游流在空间分布上存在显著差异,但最终趋于稳定;旅陕不同类别、国别入境旅游者与三大口岸关联度大小迥异。  相似文献   

17.
国土空间规划是统筹区域资源空间配置、开发管理和布局优化的总体方案,在引领区域协调发展上具有重要意义。国土空间规划必然导致土地利用类型及布局的改变,从而引起经济、社会、生态环境等方面的供给与需求变化。本研究从三生空间耦合协调的角度,通过生态系统服务和人类福祉需求的供需关系,揭示三生空间的供需连接与耦合关系。本研究借助 InVEST模型和生态服务价值当量法对生态系统服务供给与需求进行定量分析,同时引入耦合协调度模型与相对发展度模型,通过对生态系统服务供需变化进行耦合协调类型分析,探究国土空间用地结构调整所产生的供需间的协调关系,并用耦合协调状况对国土空间规划效益进行评价。研究发现,在规划期内宜宾市翠屏区生态系统服务供需总体耦合协调度呈现减小态势。2020-2035年耦合协调度从 0.60降低到 0.59,相对发展度由 1.05减小至 1.01。生态系统服务总体供给盈余明显,但由于供需分布空间差异,城镇地区为主要的供给赤字区域。影响生态系统服务需求的主要因素为环境净化需求,城市化指标对生态系统服务供需相对发展度具有较为普遍的负面影响。  相似文献   

18.
Management of river basins involves the making of informed choices about the desired levels of economic activities and ecosystem functioning in the catchment. Information on the economic and ecological effects of measures as well as their spatial distribution is therefore needed. This paper proposes the following instruments to support decision-making in river basins: (1) the linking of models and indicators to describe the economic and ecological effects of management actions and their spatial distribution and (2) an extended evaluation framework that aims to evaluate management actions on three objectives for sustainable river management. These are cost-effectiveness, spatial equity, and environmental quality. This paper illustrates the potential of these instruments for river basin management by a case-study on nutrient management in the Rhine basin. In this case-study four nutrient abatement strategies are formulated, based on policies of the International Commission for the Protection of the Rhine and the North Sea Commission. These strategies are analysed and evaluated on their contribution to the three management objectives. Results show that none of these strategies score highest on cost-effectiveness, spatial equity and environmental quality simultaneously. It appears that cost-effectiveness is in conflict with environmental quality, whereas spatial equity and cost-effectiveness show quite close correspondence. This means that a trade-off has to be made between costs and spatial equity on the one hand, and environmental standards on the other hand. This paper offers a framework to make these trade-offs more explicit and provides quantitative information on cause-effect relationships, economic and environmental effects and the spatial distribution of these effects for various management strategies. This information can be particularly useful in the development of compromises required to establish international agreement and co-operation.  相似文献   

19.
九华山国内客源市场空间结构与出游行为研究   总被引:6,自引:3,他引:6  
汪德根 《资源开发与市场》2004,20(5):342-344,347
在实地调查的基础上,分析了九华山国内客源市场空间结构及其演变特征,得出国内客源市场集中程度降低、客源吸引力不断增强、波浪式推进的演变结论,并探讨了九华山旅游行为空间模式主要以单一目的地旅游模式和区域旅游模式为主,根据旅游意向调查结果显示,九华山与黄山在客源市场方面具有较强的互补性。  相似文献   

20.
Accurate spatial representation of climatic patterns is often a challenge in modeling biophysical processes at the watershed scale, especially where the representation of a spatial gradient in rainfall is not sufficiently captured by the number of weather stations. The spatial rainfall generator (SRGEN) is developed as an extension of the “weather generator” (WXGEN), a component of the Agricultural Policy/Environmental eXtender (APEX) model. SRGEN generates spatially distributed daily rainfall using monthly weather statistics available at multiple locations in a watershed. The spatial rainfall generator as incorporated in APEX is tested on the Cowhouse watershed (1,178 km2) in central Texas. The watershed presented a significant spatial rainfall gradient of 2.9 mm/km in the lateral (north‐south) directions based on four rainfall gages. A comparative analysis between SRGEN and WXGEN indicates that SRGEN performs well (PBIAS = 2.40%). Good results were obtained from APEX for streamflow (NSE = 0.99, PBIAS = 8.34%) and NO3‐N and soluble P loads (PBIAS ≈ 6.00% for each, respectively). However, APEX underpredicted sediment yield and organic N and P loads (PBIAS: 24.75‐27.90%) with SRGEN, although its uncertainty in output was lower than WXGEN results (PBIAS: ?13.02 to ?46.13%). The overall improvement achieved in rainfall generation by SRGEN is demonstrated to be effective in the improving model performance on flow and water quality output.  相似文献   

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