共查询到20条相似文献，搜索用时 109 毫秒
1.
介绍了茄子绵疫病发病症状，分析了发生原因与栽培技术关系密切，根据其发病规律，提出农业防治与化学防治相结合的综合防治技术，以期为茄子绵疫病的防治提供参考。 相似文献
2.
3.
4.
枣豹蠹蛾生物学与防治研究 总被引：1，自引：0，他引：1
调查研究了枣豹蠹蛾生物学特性及防治技术。枣豹蠹蛾一年发生１代，以幼虫在被害枝条内越冬，６月上旬为化蛹盛期，６月下旬～７月上旬为成虫羽化盛期，７月上旬为幼虫孵化盛期。通过发生期预测，提出以人工防治为主，配合药剂防治，药剂防治适期为成虫发生盛期后３～７ｄ，药剂可用１５００倍１６０５或２０００倍氯氰菊酯。 相似文献
5.
6.
为探究陕西省榆林市靖边县樟子松松针小卷蛾有效的防治药剂，采用不同浓度的3种药剂进行了室内防治及田间防治试验。结果表明：不同药剂对樟子松松针小卷蛾防治效果差异较大，同一药剂不同稀释倍数的防治效果也各不相同。对樟子松松针小卷蛾防治效果较好的防治药剂为1.8%阿维菌素乳油1500～2000倍液、3%高渗苯氧威乳油1000倍液，同时这2种药剂对作物、环境较为安全，是防治樟子松松针小卷蛾的理想药剂，在实际防治过程中，可交替使用这2种药剂，以控制害虫为害。 相似文献
7.
枣树绿盲蝽象的防治技术及其存在的问题与建议 总被引：1，自引：0，他引：1
目前，绿盲蝽象已成为枣树生产中的主要害虫，为对其进行有效防治，现将生产中普遍采用的各项防治技术进行总结，同时，分析了当前绿盲蝽象防治中存在的问题，并提出相应建议。 相似文献
8.
云杉梢斑螟是云杉常见虫害之一，隶属于鳞翅目螟蛾科，主要为害云杉新生的树梢和嫩叶。为了有效控制云杉梢斑螟的为害，分析了云杉梢斑螟的形态特征、生活史及其发生与环境的关系，阐述了防治云杉梢斑螟的原则，并从生物防治、物理防治、化学防治、提高监测水平、扩大宣传、促进群防群治6个方面，提出了具体的防治措施，旨在提高云杉梢斑螟防治水平，从而促进云杉林木健康生长。 相似文献
9.
葡萄是一种易发多种病害而虫害较少的果树，由于此．使人们忽视了对害虫的防治，有些产区为此常造成较大损失。结合我区的生产实际，通过2004-2009年的试验推广，总结出以下防治方案，即葡萄害虫综合防治以农业防治为主，辅以必要的化学防治即可控制其为害。 相似文献
10.
11.
红富士苹果树冠枝(梢)叶分布与温度、湿度的关系 总被引：3，自引：0，他引：3
以12a生红富士苹果(Malus.domestica Borkhcv.Red Fuji)为试材,研究了北京地区树冠不同层次和部位温度、相对湿度的分布、动态变化与枝叶数量间的关系。结果表明,树冠不同层次温度从上到下逐渐降低,同一层次内温度从内膛到外围逐步增大,树冠不同层次相对湿度从上到下逐渐增大,同一层次内相对湿度从内膛到外围逐步减小;树冠温度日变化呈白天低-高-低的趋势,相对湿度的日变化呈白天高-低-高的趋势,夜晚树体温度、相对湿度趋于一致;7—8月份冠层温度、相对湿度高于5—6月份和9—10月份。应用多元统计分析的方法建立了树冠温度、相对湿度与枝(梢)叶量关系的回归方程,冠层内不同层次、部位的温度、相对湿度受冠层内枝(梢)叶数量和分布的影响,冠层内温湿度与累计长、中、短枝(梢)量和叶面积系数成线性负相关,而相对湿度与之成线性正相关。综合分析,冠层有良好温度和相对湿度的群体结构参数为生长季每hm2总枝(梢)量100万左右,叶面积系数控制在3.5～4.0,长、中、短枝(梢)比例分别为73～77、10～12和13～15。 相似文献
12.
In Europe and North America regeneration of brownfield land is an important objective of government policy. Regeneration to greenspace in particular, has been used to help reverse social and environmental decline, with typical benefits including increased flood retention capacity, temperature regulation, habitat for wildlife, building communities, encouraging local engagement and providing space for play and recreation.Regeneration project objectives are set to maximise the benefits of greenspace creation for a given location; setting the right objectives is critical to lever funding required to pump-prime activity. However, opportunities to heighten benefits delivered through the process of regeneration can be overlooked. This research identified that there was a disconnect between practices required to meet the defined objectives for a specific site and regeneration activity. This was often due to gaps in the project delivery plans: tasks which are important to realise improvement were missing. Emphasis was often found to be on site delivery, with a benign assumption that the benefits will arise as a result of project completion. Although there are some examples of practices to optimise benefits, a lack of consistency indicates scope for improvement.A logic model was co-produced with practitioners in a bid to address this issue and support project delivery planning. The model maps the social and environmental objectives for a site against specific project delivery stages. The model was refined through a workshop exercise involving discussion with practitioners who were planning new urban greenspaces on brownfield land.This paper presents the logic model to demonstrate what needs to be considered to improve the project delivery planning process, signposting the steps required to translate project objectives into outcomes, to optimise social and environmental benefits delivered during and after regeneration. The model could support those involved in project delivery planning and help raise the overall quality of new greenspace. 相似文献
13.
Following the increasing public health concerns related to physical inactivity in the population, the relationship between outdoor recreation and public health has been increasingly acknowledged over the last decades. To improve public health, planners and policy-makers aim to provide good accessibility to recreational landscapes to facilitate outdoor recreational activity. At the same time, they are facing development pressure due to urban growth. In order for planners and policy-makers to secure people access to urban and near urban recreational areas, there is a need to map and measure access in a way that is adequate as a basis for decision-making in planning and design processes. Access is often defined as distance, or proximity, from residents’ homes to recreational areas. This paper explores different ways to map and measure distance to recreational areas, and aims to provide better decision support for planners and decision-makers. Moss municipality in Norway serves as a case study. We begin by addressing the meaning of the term ‘recreational landscape’ and how the choice of definition affects the results when mapping recreational areas. We also discuss who we are measuring distance for, and how different user groups will have different thresholds or critical distances affecting their frequency of visits to a recreational area. Last, we explore different methods for measuring distance within a GIS environment. The paper shows how the purpose of the analysis must be decisive when defining recreational landscapes and choosing methods for measuring access to recreational landscape, in order to provide valuable input to planners and policy-makers aiming at enhancing the possibility for outdoor recreation for people. 相似文献
14.
Urban greenspaces are multifunctional spaces, providing services to people and biodiversity. With space in urban areas being limited creation and maintenance of urban greenspaces relies on understanding the preferences of urban residents for their characteristics. Such preferences are expected to vary with current availability, and the availability of alternatives to greenspaces such as gardens or gyms. We carried out a nationwide discrete choice experiment with Scottish urban residents to estimate values associated with greenspace attributes of: recreational features; plants and natural features; trees; accessibility; time to walk from home and size, to test the hypotheses that: (i) people are willing to pay to maintain greenspace, (ii) people have willingness to pay for greenspaces with multiple functions, including features for direct use (e.g. play equipment) and biodiversity (e.g. wildflowers), (iii) willingness to pay for individual greenspace will vary according to socioeconomic characteristics and (iv) vary with the amount of greenspace or substitute facilities available. We find a positive willingness to pay to maintain greenspace in general, and higher willingness to pay for larger greenspaces closer to home, which are multifunctional and contain both direct use features (e.g. children’s play park) and biodiversity features. Although we find significant heterogeneity in willingness to pay for maintaining greenspace, this is not well explained by either socioeconomic characteristics or the availability of substitute facilities. Our results have relevance for urban natural capital accounting, and demonstrate to urban planners the importance of the design and maintenance of multi-functional greenspaces for urban populations and would benefit from future research that further explores heterogeneity, including perceptions of greenspace access and substitutes, and greenspace quality. 相似文献
15.
Comparison of the Sensitivity of Landscape-fire-succession Models to Variation in Terrain, Fuel Pattern, Climate and Weather 总被引：1，自引：0，他引：1
Geoffrey J. Cary Robert E. Keane Robert H. Gardner Sandra Lavorel Mike D. Flannigan Ian D. Davies Chao Li James M. Lenihan T. Scott Rupp Florent Mouillot 《Landscape Ecology》2006,21(1):121-137
The purpose of this study was to compare the sensitivity of modelled area burned to environmental factors across a range of
independently-developed landscape-fire-succession models. The sensitivity of area burned to variation in four factors, namely
terrain (flat, undulating and mountainous), fuel pattern (finely and coarsely clumped), climate (observed, warmer & wetter,
and warmer & drier) and weather (year-to-year variability) was determined for four existing landscape-fire-succession models
(EMBYR, FIRESCAPE, LANDSUM and SEM-LAND) and a new model implemented in the LAMOS modelling shell (LAMOS(DS)). Sensitivity
was measured as the variance in area burned explained by each of the four factors, and all of the interactions amongst them,
in a standard generalised linear modelling analysis. Modelled area burned was most sensitive to climate and variation in weather,
with four models sensitive to each of these factors and three models sensitive to their interaction. Models generally exhibited
a trend of increasing area burned from observed, through warmer and wetter, to warmer and drier climates with a 23-fold increase
in area burned, on average, from the observed to the warmer, drier climate. Area burned was sensitive to terrain for FIRESCAPE
and fuel pattern for EMBYR. These results demonstrate that the models are generally more sensitive to variation in climate
and weather as compared with terrain complexity and fuel pattern, although the sensitivity to these latter factors in a small
number of models demonstrates the importance of representing key processes. The models that represented fire ignition and
spread in a relatively complex fashion were more sensitive to changes in all four factors because they explicitly simulate
the processes that link these factors to area burned.
The US Government's and the Canadian Government's right to retain a non-exclusive, royalty-free license is acknowledged 相似文献
16.
以6年生果实膨大后期‘赤霞珠’葡萄为试材,运用13C和15N标记技术,分别标记不同部位和节位的枝条叶片,研究碳氮营养吸收分配规律。结果表明:标记近主干和远主干枝条叶片,叶片合成的光合产物和吸收的氮素营养在近主干和远主干枝条之间不相互转运,近主干枝条上的果实对光合产物的征调能力强于远主干枝条上的果实,δ值(表示固定的13C同化物的量)是远主干枝条上果实的4.74倍;同一枝条不同节位的标记叶片距结果部位越近,果实的δ值和Ndff值越大,说明果实优先征调距果实近的叶片碳氮素营养;副梢保留6片叶所固定的光合产物总量和吸收的氮素营养总量均大于保留2片叶的,分别是其1.1倍和1.8倍。 相似文献
17.
Sustainable sources of funding for investment in Green Infrastructure have become increasingly difficult to identify due to centralised government financing cuts in the UK. Although local government, as traditional normative funders, have adopted innovative approaches to capital and revenue spending there remains a significant gap in how and what resources are supported. Business Improvement Districts (BIDs) are one set of stakeholders that potentially have a role to play in addressing funding deficits. As subscriber funded organisations, they work at a local level to enhance economic prosperity, as well as delivering socio-cultural and ecological enhancement in identified urban areas. This paper examines the experience of BIDs in London to debate the influences and barriers to their investing in Green Infrastructure. It argues that BIDs can act as critical advocates for Green Infrastructure planning where the latter aligns with local economic objectives. Moreover, we identify spatial variations in the extent to which BIDs in London engage with Green Infrastructure in their documentation and practice, illustrating differences in the perceived value of the concept. We conclude that BIDs hold the potential to facilitate investment in Green Infrastructure due to their position as conduits of business, local government, and community objectives. However, to fully embrace this role balance is needed between the setting of environmental objectives and the need to support local business needs, land ownership issues, and capital/revenue financing considerations. 相似文献
18.
Solène Croci Alain Butet Anita Georges Rahim Aguejdad Philippe Clergeau 《Landscape Ecology》2008,23(10):1171-1186
To evaluate the importance of urban woodlands to serve as potential sites for biodiversity conservation, we analysed bird,
carabid beetle and small mammal community responses to urbanisation at different spatial scales. We analysed the relationships
between the variations of the structure (species richness S, diversity H′ and dominance D) of animal communities of woodlands
distributed along a rural–urban gradient, and the variations along this same gradient of (1) the vegetation within woodlands,
(2) the landscape at 100 m and (3) 600 m around the woodlands. We identified the spatial scales whose variations along the
gradient most affected each animal community structure, and characterised community responses to these variations. Our results
showed that urbanisation affected taxa differently according to their dispersal ability. Carabid beetles, less mobile, seem
to be sensitive to increasing fragmentation and built surfaces from periurban to town centre which could make their movement
within the urban landscape difficult. Birds, mobile species, seem to be more sensitive to variations of the vegetation structure
within woodlands from periurban to town centre that could affect their capacity to maintain in habitat patches. Although our
study did not allow relating the small mammal community structure to urbanisation, it suggests that this taxa is sensitive
to urban local disturbances. A relevant management scale of woodlands can be specified for each taxa conservation. Urban woodlands
accommodate over 50% of the species present in periurban woodlands, and effective management could enhance this number. Woodlands
seem to be a good choice for promoting biodiversity conservation in towns. 相似文献
19.
Green spaces are vital to the wellbeing of urban communities, largely due to the many Cultural Ecosystem Benefits (CEB) that nature contributes to outdoor recreation experiences (e.g., relaxation, inspiration, spiritual enrichment). To ensure equity in the distribution of CEB, however, we require a better understanding of how they relate to ethnicity. Through 100 in-situ semi-structured interviews with green space users in the Lee Valley Regional Park, London, UK, this research explored variation in outdoor recreational CEB based on i) ethnicity and ii) green space activity and attribute preferences. We compared green space preferences and CEB of Black, Asian and minority ethnic (BAME) and white users of two distinct types of urban green space: parks and more biodiverse Sites of Special Scientific Interest (SSSIs). Both white and BAME visitors to parks prioritized games/sports and built features whereas visitors to SSSIs more often undertook wildlife viewing and prioritized natural features. However, we found that white and BAME users of both types of urban green space derived similar CEB. Peace and relaxation were primary among these benefits, a result of both nature interaction and its contrast to the urban environment. These results demonstrate that nature does not have to be the focal point of outdoor recreation to contribute to wellbeing; rather, even as a backdrop to sports and cultural activities, nature provides similar benefits to green space users. To promote use of green space and foster intercultural understanding, we recommend integrating these shared benefits obtained from nature within marketing and engagement strategies. Future research is needed to explore CEB variation within and among distinct ethnic communities to fully capture the diversity of lived experiences. 相似文献
20.
为进一步发掘新一轮退耕还林工程的研究热点及趋势,以新一轮退耕还林为主题,基于2012-2022年CNKI平台中的数据库,取300条样本,运用CiteSpace可视化分析的方法,深入解析我国新一轮退耕还林相关研究,包括研究机构合作网络、作者合作网络、关键词聚类图谱、关键词时区图谱和关键词突现图谱等方面。结果表明：(1)有关退耕还林的相关文献数量呈现先增加后下降的趋势。(2)有关我国新一轮退耕还林的研究文献主要围绕“后续产业”“农户收入”“生态效益”等问题展开,高频关键词显示新一轮退耕还林需要转变发展方式,要向高质量、可持续发展的方向转变,一味地扩大生态林规模并不可取。(3)退耕还林研究以对社会经济状况与初期退耕还林措施的综合改进分析为始发点,逐渐转变为以社会经济和生态效益的相互交织并存,并逐渐向以生态效益为主题逐步细分进行发展。所以,科研理念、方法之间的交融与并行以及怎样继续巩固和拓展退耕还林成果,如何合理的扩大退耕还林规模、保障农村环境安全、提高退耕农户增收,成为了今后科学研究发展的重要关键。 相似文献