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1.
疏干水资源化利用是将煤矿开采废水经处理后用于煤化工生产,其不仅可以缓解旱区煤炭及化工企业面临的水资源供需矛盾,而且还能改善生态环境。目前疏干水资源化利用项目已在蒙陕地区部分煤化工企业实施,但其具体效益尚未明了,文中以已实施该项目的煤化工企业为典型,采用静态和动态评价分析企业实施该项目产生的经济效益,定义并计算各评价指标,同时定性定量描述其社会、生态环境效益,构建完整综合的评价体系,从而全面阐释该项目各方效益,结果显示疏干水资源化利用项目经济、社会、生态环境效益显著,建议在行业及区域推广以促进旱区水资源可持续发展。  相似文献   
2.
王宏春 《园艺与种苗》2021,(3):73-74,78
通过对繁昌县平铺镇农村人居环境整治情况的调查,发现存在整治难、维护难等一系列问题,对其成因进行了分析,并提出了相应的应对措施。  相似文献   
3.
新疆农村被动式太阳房夏季不同降温控制模式的降温效果   总被引:3,自引:2,他引:1  
冬季供暖性能良好的被动式太阳房,夏季室内普遍存在着过热问题。该文以新疆石河子农村的2栋不同构造的被动式太阳房为研究对象,提出4种不同的降温控制模式。通过夏季降温试验研究,重点讨论了白天热压通风、夜间自然通风、地板辐射供冷等措施对于缓解被动式太阳房夏季过热程度的作用,并在此基础上分析了降温措施对室内热舒适适应性的影响程度。试验结果表明:对于新疆农村没有地下室的被动式太阳房,采用该文提出的热压通风结合夜间通风降温模式,满足80%可接受舒适度要求的时长占比可提升35.04%;耦合地下室的被动式太阳房,依靠合理的通风措施和地板辐射供冷,满足80%可接受舒适度的时长占比达到85.80%,可基本实现夏季降温的目标。  相似文献   
4.
Soil loss from riparian areas supporting the annual invasive weed, Impatiens glandulifera (Himalayan balsam), was measured and compared with equivalent values recorded at nearby, topographically similar areas supporting perennial vegetation over a cumulative seven-year period, along sections of two separate river systems; one in Switzerland, and one in the UK. Soil loss from colonised locations was significantly greater than from reference locations in four of the seven measurement periods. Despite contrasting results, standard deviations, based on soil losses and gains, were predominantly higher for colonised areas at both rivers over most monitoring periods. These findings indicated that areas colonised by Himalayan balsam experience higher sediment flux in comparison with areas free of invasion. Here, we test those original interpretations by reinterrogating the datasets using a more robust analysis of inequality. Nine datasets were tested, five of which (i.e. 56%) showed that sediment flux was significantly greater at Himalayan balsam-invaded areas than at reference areas. Three datasets showed no difference in sediment flux between invaded and reference areas (33%), and one (11%) showed higher sediment flux at reference areas. Most results uphold our original interpretations and support our hypothesis that hydrochory probably dictates where colonisation initially occurs, by depositing Himalayan balsam seeds in slack or depressional areas along river margins. Once Himalayan balsam becomes established and sufficient perennial vegetation is displaced, seasonal die-off and depleted vegetation cover may increase the risk that some areas will experience significantly higher sediment flux.  相似文献   
5.
为了探索福建省茎用芥菜1年2代繁育技术,选择6个茎用芥菜品种,分别进行冬春季正常繁育和夏秋季高山加代繁育的2代繁育试验,并对比各品种2代繁育的生育期、株高、株幅和种子产量。结果表明:所有参试茎用芥菜品种只要通过打破种子休眠、衔接好2代繁育的播种期都能完成1周年2代繁育,夏秋季高山加代繁育的全生育期比冬春季正常繁育平均缩短约50 d;冬春季繁育比夏秋季高山加代繁育株高增加31.2%~132.9%,株幅增加1.5%~21.8%,所有参试品种冬春季繁育的种子产量都极显著高于相应夏秋季高山加代繁育,种子产量增加17.8%~153.6%。  相似文献   
6.
【目的】科学客观地进行土地生态安全评价,提出可行有效的土地生态系统优化对策,为桂西资源富集区土地生态安全的维护及未来发展提供参考。【方法】基于BP神经网络方法构建土地生态安全评价模型,通过分析影响土地生态系统的自然、经济、社会3个主导因素,建立桂西资源富集区土地生态安全评价指标系统,对2008—2017年桂西资源富集区土地生态安全程度进行评价。【结果】桂西资源富集区2008—2017年土地生态安全程度均属于一般安全状态,且由一般安全状态逐步接近较安全状态;其中百色市、河池市、崇左市分别在不同因素下的土地生态安全程度存在较大差异,且差异在逐年增大。【结论】为了避免桂西资源富集区土地生态安全系统存在发展失衡的倾向,建议桂西资源富集区政府优化营商环境,坚持"绿水青山就是金山银山";制定合理的耕地保护政策,缓解人地矛盾关系。  相似文献   
7.
本试验旨在研究在湖羊全混合颗粒料中添加不同类型蛋氨酸(蛋氨酸钙盐与蛋氨酸羟基类似物异丙酯)对湖羊生长性能及血清生化指标、抗氧化指标和激素含量的影响。选取体重为(19.99±2.04) kg的健康湖羊72只,随机分为3组:对照组、试验Ⅰ组(在基础饲粮中添加1.5 kg/t蛋氨酸钙盐)和试验Ⅱ组(在基础饲粮中添加1.5 kg/t蛋氨酸羟基类似物异丙酯),每组6个重复,每个重复4只(公母各占1/2)。预试期7 d,正试期80 d。结果表明:1)与对照组相比,试验Ⅰ组、试验Ⅱ组总增重、平均日增重均有上升的趋势,其中试验Ⅰ组总增重提高了12.8%(P>0.05),试验Ⅱ组总增重提高了3.1%(P>0.05);料重比方面,试验Ⅰ组、试验Ⅱ组均有下降的趋势,其中试验Ⅰ组下降了12.2%(P>0.05),试验Ⅱ组下降了3.6%(P>0.05)。2)试验Ⅱ组血清甘油三酯(TG)、总胆固醇(TCH)、低密度脂蛋白胆固醇(LDL-C)、总蛋白(TP)含量显著高于对照组和试验Ⅰ组(P <0.05)。3)血清抗氧化指标及激素含量各组之间无显著差异(P>0.05)。综上所述,全混合颗粒料中添加蛋氨酸羟基类似物异丙酯及蛋氨酸钙盐具有提高肉羊生长速度、降低料重比的趋势,同时影响部分血清生化指标,但对血清抗氧化指标及激素含量无显著影响。  相似文献   
8.
评估人工灌丛植被重建对干旱半干旱区陆地生态系统蒸散的影响,不仅能揭示植被变化与水文过程的耦合机理,又可为区域生态治理与水资源管理提供科学指导。该研究利用Landsat-8OLI/TIR遥感影像及气象数据等驱动SEBAL模型,反演宁夏盐池县的年内不同日期的陆表蒸散,结合目视解译选取的人工灌丛区与对照草地,评估了人工灌丛植被对陆表蒸散的影响。结果表明:1)SEBAL模型的蒸散反演精度与站点观测结果较为一致,可用于干旱半干旱区蒸散反演及空间特征研究;2)盐池县人工灌丛植被区日平均蒸散为1.20mm/d,高于对照草地1.17mm/d的日平均蒸散量,即干旱半干旱区人工种植灌木林增加了生态系统水分消耗,但不同季节和不同生物地理条件下的蒸散增强作用存在差异,蒸散增强在8月份最大,而3、4月份呈现负效应;3)人工灌丛的密度越大、植被盖度越高,对陆表蒸散的增强作用越强,特别在NDVI0.4的高盖度情况下蒸散增强作用更加明显。由此可知,在水资源紧缺的干旱半干旱区开展以灌木树种为主的植被重建需在合理的生态水文阈值范围内开展,才能构建出稳定可持续的人工生态系统。  相似文献   
9.
  1. Marine protected areas (MPAs) and freshwater protected areas (FPAs), collectively aquatic protected areas (APAs), share many commonalities in their design, establishment, and management, suggesting great potential for sharing lessons learned. However, surprisingly little has been exchanged to date, and both realms of inquiry and practice have progressed mostly independent of each other.
  2. This paper builds on a session held at the 7th World Fisheries Congress in Busan, South Korea, in May 2016, which explored crossover lessons between marine and freshwater realms, and included case studies of four MPAs and five FPAs (or clusters of FPAs) from nine countries.
  3. This review uses the case studies to explore similarities, differences, and transferrable lessons between MPAs and FPAs under five themes: (1) ecological system; (2) establishment approaches; (3) effectiveness monitoring; (4) sustaining APAs; and (5) challenges and external threats.
  4. Ecological differences between marine and freshwater environments may necessitate different approaches for collecting species and habitat data to inform APA design, establishment and monitoring, but once collected, similar spatial ecological tools can be applied in both realms. In contrast, many similarities exist in the human dimension of both MPA and FPA establishment and management, highlighting clear opportunities for exchanging lessons related to stakeholder engagement and support, and for using similar socio‐economic and governance assessment methods to address data gaps in both realms.
  5. Regions that implement MPAs and FPAs could work together to address shared challenges, such as developing mechanisms for diversified and sustained funding, and employing integrated coastal/watershed management to address system‐level threats. Collaboration across realms could facilitate conservation of diadromous species in both marine and freshwater habitats.
  6. Continued exchange and increased collaboration would benefit both realms, and may be facilitated by defining shared terminology, holding cross‐disciplinary conferences or sessions, publishing inclusive papers, and proposing joint projects.
  相似文献   
10.
Thailand aims to increase the use of renewable and alternative energy by 25% of total consumption under the Alternative Energy Development Plan (AEDP 2012–2021) by 2021, which include outputs from energy crops. This initiative is likely to put pressure on land resources, especially near parks and protected areas. Our study examined energy crop plantations, farmer responses to the AEDP, and community roles in forest protection in four villages adjacent to Phu Wiang National Park, Thailand in 2014. The majority of respondents (80%, n = 50) used their land for rice cultivation, but many villagers increased plantings of sugarcane (54%) and cassava (20%) because of high market demand for energy crops. Only a few examples of agricultural expansion into the national park were observed. Nevertheless, encroachment is likely to occur at this and other national parks as a result of government incentives to plant energy crops and the limited availability of agricultural land. Reliance on community-based management strategies may not be powerful enough for villagers to withstand the pressures of modernization, materialism, and other socioeconomic influences, possibly negating the effect of sustainability. Striking an equitable balance between government policies, community development, and forest protection will be a challenge for resource managers.  相似文献   
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