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据报道,我国今后农药使用趋势是: 1.目前大力推广使用的有9种:三环唑、富士一号、粉锈宁、特克多、水胺硫磷、混灭威、敌鼠钠盐、丁草胺、草甘膦。 2.近年内仍可继续用的有22种:井冈霉素、多菌灵、托布津、克瘟散、叶青双、叶枯宁、叶枯净、萎锈灵、克菌丹、乙磷铝、杀虫双、叶蝉散、速灭威、辛硫磷、乙酰、敌敌畏、二嗪农、乐果、氧化乐果、马拉松、二溴磷、倍硫膦。 3.逐步控制使用的有24种:百菌清、敌菌灵、401、甲胺磷、磷铵、久效磷、1605、3911、治螟灵、呋喃丹、杀虫胀、二氯苯醚菊酯、溴氰菊酯、氯氰菊酯、多虫畏、速灭杀丁、杀灭菊酯、溴甲 相似文献
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据统计,彭县有药用植物630余种,隶属150科。其中药用低等植物10种,主要为蝉花、长松萝,节松萝、雪茶等。药用蕨类植物40种,主要有石松、木贼、海金沙、单芽狗脊蕨、槲蕨、石苇等。药用种子植物580余种,其中裸子植物有银杏、侧柏等5种、双子叶植物460余种,单子叶植物93种,主要有首乌、药用大黄、川牛膝、连、黄连、三叶木通,牡丹、厚朴、杜仲、贴梗海棠、杏、橘,吴茱萸、黄皮树、楝、酸枣、紫花地丁、羽叶三七、川芎、蒿本,重齿毛当归、防风、北柴胡、紫花前胡、益母草、薄荷、玄参、双边瓜蒌、忍冬、党参、桔梗、牛蒡、白术、云木香、红花、泽泻、天南星、天门冬、米贝母、玉竹、土茯苓、藜芦、射干、姜、白芨、天麻等。药用动物有40余种,分属33科,主要有地龙、蝉蜕、九香虫、僵蚕、虻虫、蜂蜜、蜂蜡、羌活鱼、龟板、鳖甲、乌梢蛇、鸡内金、夜明砂、狗肾、豹骨、穿山甲,牛黄、猴骨等.矿物药有空青石、绿矾、滑石、禹余粮、硫磺,自然铜和种乳石等7种.目前彭县中草药已正式收入中国药典1985年版的 相似文献
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省、自治区、直辖市控制区范围(国家重点扶持的贫困县除外)北京市东城区、西城区、宣武区、崇文区、朝阳区、海淀区、丰台区、石景山区及门头沟区、通州区、房山区、昌平县、大兴县天津市市区河北省石家庄市市区及辛集市、藁城市、晋州市、新乐市、鹿泉市邯郸市市区及武... 相似文献
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沙棘(Hippophae rhamnoides Linn.)又名醋柳、酸刺、黑刺等,是胡颓子科沙棘属落叶或小乔木。广泛分布于大西洋沿岸和欧洲西部斯堪的纳维亚南部,直至巴尔干、土尔其、伊朗、阿富汗、蒙古、巴基斯坦、印度北部以及我国辽宁、内蒙古、河北、山西、陕西、甘肃、宁夏、青海、新疆、西藏、四 相似文献
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中国海滨旅游研究进展 总被引:2,自引:0,他引:2
在阅读大量相关文献资料的基础上,试图从海滨旅游兴起的原因、海滨旅游主体、海滨旅游客体及海滨旅游主客体间关系4个方面对近年来国内有关海滨旅游的研究作一系统综述.在此基础上,对中国海滨旅游以后的研究进行了展望. 相似文献
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Impacts of Camping on Vegetation: Response and Recovery Following Acute and Chronic Disturbance 总被引:3,自引:0,他引:3
Experiments with controlled levels of recreational camping were conducted on previously undisturbed sites in two different plant communities in the subalpine zone of the Wind River Mountains, Wyoming, USA. The plant communities were coniferous forest with understory dominated by the low shrub Vaccinium scoparium and a riparian meadow of intermixed grasses and forbs, of which Deschampsia cespitosa was most abundant. Sites were camped on at intensities of either one or four nights per year, for either one (acute disturbance) or three consecutive years (chronic disturbance). Recovery was followed for three years on sites camped on for one year and for one year on sites camped on for three years. Reductions in vegetation cover and vegetation height were much more pronounced on sites in the forest than on sites in the meadow. In both plant communities, increases in vegetation impact were not proportional to increases in either years of camping or nights per year of camping. Close to the center of campsites, near-maximum levels of impact occurred after the first year of camping on forested sites and after the second year on meadow sites. Meadow sites recovered completely within a year, at the camping intensities employed in the experiments. Forest sites, even those camped on for just one night, did not recover completely within three years. Differences between acute and chronic disturbance were not pronounced. 相似文献
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大气氮沉降增加是全球变化的重要现象之一,草原生态系统对氮沉降增加的响应成为草地生态学的研究热点之一。凋落物分解是草原生态系统养分循环和能量流动的主要途径,氮沉降增加引起草原植物群落结构变化,导致凋落物质量、土壤肥力、土壤微生物和土壤动物的变化,最终影响凋落物的分解。本文综述了氮沉降对草原凋落物结构、化学组成和分解环境的影响等方面的国内外最新研究进展,讨论了需进一步加强研究的内容,以期为进一步拓展该领域研究的广度和深度、为全面分析和评估全球变化对草原生态系统的影响提供参考。 相似文献
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Landscape ecological assessment: a tool for integrating biodiversity issues in strategic environmental assessment and planning 总被引:11,自引:0,他引:11
To achieve a sustainable development, impacts on biodiversity of urbanisation, new infrastructure projects and other land use changes must be considered on landscape and regional scales. This requires that important decisions are made after a systematic evaluation of environmental impacts. Landscape ecology can provide a conceptual framework for the assessment of consequences of long-term development processes like urbanisation on biodiversity components, and for evaluating and visualising the impacts of alternative planning scenarios. The aim of this paper was to develop methods for integrating biodiversity issues in planning and strategic environmental assessment in an urbanising environment, on landscape and regional levels. In order to test developed methods, a case study was conducted in the region of Stockholm, the capital of Sweden, and the study area embraced the city centre, suburbs and peri-urban areas. Focal species were tested as indicators of habitat quality, quantity and connectivity in the landscape. Predictive modelling of habitat distribution in geographic information systems involved the modelling of focal species occurrences based on empirical data, incorporated in a landscape ecological decision support system. When habitat models were retrieved, they were applied on future planning scenarios in order to predict and assess the impacts on focal species. The scenario involving a diffuse exploitation pattern had the greatest negative impacts on the habitat networks of focal species. The scenarios with concentrated exploitation also had negative impacts, although they were possible to mitigate quite easily. The predictions of the impacts on habitats networks of focal species made it possible to quantify, integrate and visualise the effects of urbanisation scenarios on aspects of biodiversity on a landscape level. 相似文献
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M. A. Arthur G. B. Coltharp D. L. Brown 《Journal of the American Water Resources Association》1998,34(3):481-495
ABSTRACT: Forest land managers are concerned about the effects of logging on soil erosion, streamflow, and water quality and are promoting the use of Best Management Practices (BMPs) to control impacts. To compare the effects of BMP implementation on streamwater quality, two of three small watersheds in Kentucky were harvested in 1983 and 1984, one with BMPs, the other without BMPs. There was no effect of clearcutting on stream temperatures. Streamflow increased by 17.8 cm (123 percent) on the BMP watershed during the first 17 months after cutting and by 20.6 cm (138 percent) on the Non-BMP watershed. Water yields remained significantly elevated compared to the uncut watershed 8 years after harvesting. Suspended sediment flux was 14 and 30 times higher on the BMP and Non-BMP Watersheds, respectively, than on the uncut watershed during treatment, and 4 and 6.5 times higher in the 17 months after treatment was complete. Clearcutting resulted in increased concentrations of nitrate, and other nutrients compared to the uncut watershed, and concentrations were highest on the non-BMP watershed. Recovery of biotic control over nutrient losses occurred within three years of clearcutting. The streamside buffer strip was effective in reducing the impact of clearcutting on water yield and sediment flux. 相似文献
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State of the environment reporting (SoER) is a well-established and widely applied environmental management tool in the South African context. Despite a wealth of knowledge about conducting and preparing SoERs, there is a paucity of research on the effect SoER has had on decision-making at the local government sphere. This study investigated the effect of SoER on decision-making for a sample of municipalities in the Gauteng Province of South Africa. The methodology relied on interviews with key role players, which include the ‘‘environmental function’' as well as ‘‘other functions’' responsible for infrastructure development and planning within the municipalities. The results show that notwithstanding the extensive time and resources spent on SoER, it appears to have had a limited effect on decision-making, especially beyond the environmental function. Recommendations to improve the influence of SoER on decision-making in developing countries include improved clarity on the purpose and home of SoER within municipalities, adequate budget and capacity, and effective cooperative governance both within the municipalities, and with other spheres of government. 相似文献
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本文基于2011—2019年我国31个省级行政区的面板数据,探究了数字经济发展对区域环境质量的影响。研究发现,总体来说,数字经济对环境质量具有显著的改善作用;数字经济对环境质量的改善作用在2014—2019年显著,在中部和西部省份显著,在环境污染程度较高的省份显著。传导机制检验表明,经济规模扩张、产业结构优化及绿色技术创新在数字经济对环境质量的作用机制中发挥中介作用。进一步分析表明,政府竞争在数字经济对环境质量的改善作用中起着负向调节作用,制度环境在数字经济对环境质量的作用机制中发挥正向调节作用。因此,应高质量地推动数字经济发展、充分发挥数字经济的环境质量改善作用、匡正地方政府的竞争行为及努力营造良好的制度环境,以改善环境质量。 相似文献
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城镇建设用地需求预测与配置研究 总被引:11,自引:0,他引:11
针对我国现行城镇建设用地预测方法存在的问题,对城镇建设用地预测方法进行了探索性研究;通过构建科学的建设用地需求预测方法,为土地利用规划提供科学依据。在C—D生产函数的基础上,提出了土地、资本与产出GDP的要素关系模型、恩格尔系数与人均建设用地面积关系模型和时间序列的ARIMA建设用地模型。对成都市城镇建设用地总量进行了实证分析,对4种预测方法的结果进行了定量评价,并据此提出成都市建设用地的配置方案。 相似文献
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秦皇岛港东港区煤尘污染与气象特征关系分析 总被引:4,自引:0,他引:4
本文分析了秦皇岛港东港区煤尘污染与气象条件的关系,分析结果表明,表征煤尘污染的因子总悬浮颗粒物及降尘与自然降水、大风等气象因子具有明显的相关性,并依据分析提出了相应的管理建议。 相似文献