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381.
青藏高原农牧业生态风险时空变化特征与分区防控   总被引:1,自引:0,他引:1  
青藏高原地区是我国重要的生态安全屏障、战略资源储备基地,农牧业是青藏高原涵盖范围最广的产业,明晰其生态风险对实现青藏高原农牧业可持续发展具有重要意义。构建了青藏高原农牧业生态风险评价体系,并以216个县域为评价单元,分析1990—2015年农牧业开发综合生态风险的时空分布及其重心转移规律,并结合区域农牧业开发强度实现农牧业生态风险权衡分区。结果表明:(1)青藏高原综合生态风险总体有上升趋势,呈“东部多核聚集、西部零星散列”的分布格局。(2)风险重心向西北方向移动,风险主趋势方向转为西北—东南走向。(3)青藏高原限制开发区面积占比最大为50.84%,其次为发展预警区与自然恢复区,青藏高原整体农牧业开发强度较高,应在保障高原生态安全屏障功能的情况下减缓农牧业开发。针对区域特征提出农牧业发展方案,以期为青藏高原地区农牧业开发生态风险防范及发展规划提供科学指引。  相似文献   
382.
实施农业农村现代化创新发展措施,将有效促使乡村振兴战略长远推进,形成我国农业农村创新发展的新局面。基于甘肃省86个县域研究单元,从创新投入、创新保障、创新效果三个维度构建了包含28个二级指标的农业农村创新发展评价指标体系,就农村地区创新发展水平进行综合评价。结果表明:(1)甘肃省农业农村整体创新发展得分呈上升趋势,但增长幅度较为缓慢。综合创新能力得分较高的县(区)主要集中在河西地区东部,得分较低的县(区)主要集中在南部民族地区。河西地区创新保障和创新效果水平处于全省前列,南部民族地区创新投入水平较低。(2)全省农业农村创新发展在东西方向上表现为西高东低,2013年以后逐渐表现出“两头高、中间低”趋势;在南北方向上表现北高南低;在东南—西北方向上呈现出西北高、东南低;在西南—东北方向上呈现出东北高、西南低。创新发展指数方向特征未发生明显变化,在空间上具有一定的锁定性。(3)创新发展热点区域集中在河西地区张掖市、武威市及金昌市,冷点区域集中分布在南部民族地区;极冷点区和极热点区数量减少,县域农业农村创新发展差距在减小。(4)多元资本投入、农业经济发展、自然地理条件及资源禀赋、农业基础设施配置、农业发展政策等通过内外因素结合创新发展供需两侧作用于甘肃省农业农村创新发展时空演化。  相似文献   
383.
低碳技术创新的双重外部性与“搭便车”风险严重制约了我国低碳技术创新联盟的稳定发展。基于此背景,运用随机博弈模型分析多主体惩罚机制对低碳技术创新联盟演化的影响,结果表明:多主体惩罚机制的实施能有效提升低碳技术创新联盟的稳定性。其中,第二方惩罚机制是影响低碳技术创新联盟稳定性的主要因素,第一方与第三方惩罚机制及随机干扰则对联盟的稳定速率有重要影响。为促进我国低碳技术创新联盟稳定发展,助力“碳达峰、碳中和”目标的实现,进一步从政策制定与管理实践角度提出优化我国低碳技术创新联盟稳定性的对策建议。  相似文献   
384.
“十四五”时期,我国进入了以降碳为重点战略方向、推动减污降碳协同增效的发展阶段。推进工业园区清洁生产审核能有效提升园区清洁生产水平,对于促进工业领域绿色低碳转型具有重要意义。本研究首先回顾了我国工业园区的发展历程,梳理了我国工业园区的发展现状,提出工业园区发展面临的问题及开展清洁生产审核的必要性;其次,分别从政策、研究、实践层面详细论述了工业园区推进清洁生产审核的进展;再次,分析推进工业园区清洁生产审核存在的问题;最后,建议下一步从完善政策支撑体系、加强方法学研究、强化试点示范作用三个方面推进工业园区清洁生产审核。本研究将为我国推进工业园区清洁生产审核提供理论依据和政策支持。  相似文献   
385.
ABSTRACT

The concept of an agro-production park combines industrial with environmental and animal friendly agriculture. In The Netherlands, academics and government introduced this idea—what we consider a boundary concept—to align economic and environmental ambitions. In this contribution, we argue that boundary concepts are important in deliberations as they create a sphere of engagement that enables participants to scrutinize their routines and to explore new interpretations and practices that replace their normal ways. In this way we ground the notion of ‘reflexive governance’ in deliberative practices for sustainable agriculture. We explored if and how the concept of an agropark induced frame-reflective conversations about conflicting and overlapping interpretations. We conducted a frame analysis of four Dutch national newspapers from which we derived four possible interpretations of an agropark: Pigs in the City, Surviving Farmers, Pigs in the Mud and Surviving Citizens. Next, we analysed 10 deliberative sessions about agroparks to study if reflectivity occurred. Our findings suggest that to move to more sustainable agriculture, the introduction of innovative boundary crossing concepts invites participants to reflect on conflicting frames and engage in reflective governance. However, facilitators and governmental actors need to support this boundary crossing for it to become tangible.  相似文献   
386.
农业生态观光园规划设计研究   总被引:1,自引:0,他引:1  
农业生态观光园在规划设计理念上必须体现观光、休闲、生态环保和教育综合性特点,满足都市游客在快节奏城市生活压力下渴望回归田园的心理需求,因此在农业观光园的设计过程中必须始终保持以科技支撑的现代生态农业为载体,在规划和景观设计上注重时代性与传统性的结合,最大限度地体现自然性。生态观光园规划设计应表现自然生态环保理念,具有包容性、完善的功能设施和高质量的服务。  相似文献   
387.
Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far‐reaching consequences within aquatic ecosystems.  相似文献   
388.
In this paper, we explored how aridity influences the regional deforestation and land-use patterns (i.e. crops/pastures) in South American Dry Chaco. To do this, we contrasted land use during last decade (2001–2012) with a spatially explicit aridity index, which we complemented with a crop water balance model. Land-use classifications were performed by considering the temporal variability of NDVI from MODIS satellites, showing that 40 and 60% of deforested land was assigned to crops and pastures, respectively. Results indicate that although the regional deforestation pattern was not associated with the aridity gradient, with drier areas similarly deforested as wetter areas, contrasting differences were observed in the use of this land, with crops mostly located (90%) in wetter areas and pastures evenly distributed across the whole aridity gradient. This research highlighted the strong effect of water limitations on the land-use option after deforestation and may help to set the basis for future land-use planning policies.  相似文献   
389.
Past decades have witnessed the rise of sustainable agriculture movements throughout the world. In parallel with this international trend, ecological agriculture (with essential goals of food security, rural employment, poverty alleviation, natural resource management and environmental protection) has been advocated as a workable approach for the realization of sustainable agriculture in China. Two decades of ecological agricultural development have shown that it not only gained legitimacy at the senior policy level but also became a focus of scientific research in fields such as ecological economics, ecology, and agricultural and environmental sciences. However, this endeavour is hardly known in the West and little attention has been paid so far to examining the broader politico-economic and sociocultural contexts within which it has evolved. This paper attempts to provide a general review of the emerging background, development history, policy initiatives and recent tendencies of ecological agriculture. In addition, the extant problems and potential contributions of this alternative practice to China's sustainable agricultural development are discussed. The purpose of this study is to identify the gap between the policy rhetoric and practical implementation of Chinese ecological agriculture and therefore to facilitate its moving towards sustainable development.  相似文献   
390.
廉同辉  袁勤俭 《自然资源学报》2013,28(10):1827-1834
国际标准产业分类体系是目前国际上最有影响和权威的产业分类体系。深入了解国际标准产业分类体系中农、林、牧、渔业分类演化,对正确收集、处理和测算我国农、林、牧、渔业的指标以及国际间数据比较至关重要。论文首先详细地剖析国际标准产业分类体系的农、林、牧、渔业的分类演化,然后依据国际标准产业分类体系的最新变化,结合我国农、林、牧、渔业现状,为我国国民经济行业分类中农、林、牧、渔业的修改和调整提供建议。  相似文献   
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