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1.
随着中医行业发展和中医药制取技术的进步,中药渣的产生也与日俱增,现年产量已超过3500万吨。利用好中药渣资源不仅能保护环境,降低企业支出,还能创造额外的巨大经济效益。本文总结了中药渣在活性成分再提取、环境治理、作为饲料或饲料添加剂、作为有机肥料与栽培基质、作为轻工业生产原料等传统生态经济化利用现状,以及开发能源物质、膳食纤维产品、纳米纤维素类产品及复合材料等高值化利用现状,以期为中医药产业实现高质量发展提供参考。  相似文献   
2.
In the context of recent studies that have begun to establish a more quantifiable understanding of the use of urban greenways, this paper presents a preliminary investigation into the patterns in which a greenway is used and the mechanism behind the pattern of use of the greenway. Factors of the location, economic situation, environment and social background have been measured and analyzed in the use intensity model to interpret their impact on the use intensity of different sections of a greenway. The results suggest that use of the Waterfront Greenway in Guangzhou is highly impacted by population density, employment density, nearby service provision and the connectivity of the greenway to other parts of the city. In this case, the use intensity model with indicators such as location, economic, environmental and social factors has been shown to be applicable to the evaluation of the use of the greenways. Results from the case study suggest that providing greenways close to the residential zones, employment centers and key public services such as hospitals and schools will increase greenway use. The surrounding network system of a greenway must be carefully considered and designed to improve the linking of the greenway to other parts of the city, to increase the number of potential visitors to the greenway.  相似文献   
3.
The management of burnt wood after a fire may affect seed predation by vertebrates due to the change produced in habitat structure. We analyze the effect of burnt wood management on post-dispersal seed predation in the Holm oak. Three plots were established in a burnt forest, with three treatments per plot: (1) non-intervention (NI, all trees left standing), (2) “partial cut plus lopping” (PCL, felling 90% of trees, cutting their main branches, leaving all the biomass in situ), and (3) “salvage logging” (SL, felling the logs for their removal and masticating the woody debris). Acorns were buried to mimic dispersal by jays or rodents two and three years after fire, with two trials per year (7200 monitored acorns), and the predation rate was evaluated until the time of seedling emergence. The spatial patterns of acorn predation were assessed by computing a transformed-Ripley's K function and Moran's I correlograms. There was a large spatial and temporal variability in acorn predation, with differences among trials, plots, and replicates within treatments and plots. Overall, PCL showed the lowest predation values (83.0% versus 87.4 in NI and 88.0 in SL). Predator species (mice versus wild boar) also differed among treatments, wild boar having a negligible effect in PCL, presumably due to the physical barrier of felled logs and branches. The results support that: (1) salvage logging offers no advantage against predators and (2) that post-fire burnt wood management alters the guild of acorn predators and may reshape the pattern of seedling establishment.  相似文献   
4.
Abstract: Consensus is a term widely used in Sāmoa and elsewhere in the Pacific. It is considered to be a key feature of decision‐making and a fundamental characteristic of fa’asāmoa and other Pacific ways of being and doing. In Sāmoa it has been a mark of the strength and continuity of the fa’a matai through the ages of colonialism, neo‐colonialism and globalisation. However, although it has evolved in many ways to take into account new social trends (for instance allowing children to take part in family discussions) and remains strong at the family and village level, its role at the national level has virtually disappeared. This is seldom stated publicly and consensus is still held up as a defining characteristic of Sāmoaness. At the same time, although the rise of dissent is given little acknowledgement, it permeates public life. One could assume, based on this result that the ideology of consensus is perpetuated in order to reduce national public debate on governance issues.  相似文献   
5.
流浪犬猫是生存于人类社会、介于宠物犬猫和野生动物之间的一类特殊动物,其生存、活动、繁衍与社区人群的利益有时会产生直接冲突.本文介绍了流浪犬猫福利的特征和内涵,指出了其存在传播狂犬病、易攻击人类、粪便污染、噪声污染等与人群利益的有关冲突,由此提出减少遗弃宠物遗弃,减少食物浪费,加强社区公共管理等人为因素控制措施,以及对流...  相似文献   
6.
During the Schmallenberg virus (SBV) epidemic, the European Food Safety Authority (EFSA) collected data on SBV occurrence across Europe in order to provide an assessment of spread and impact. By May 2013, twenty-nine countries were reporting to EFSA and twenty-two countries had reported cases of SBV. The total number of SBV herds reported was 13,846 and the number of SBV laboratory confirmed herds was 8730. The surveillance activities were based on the detection of SBV clinical cases (either adults or newborns). Malformation in newborns was the most commonly reported clinical sign of SBV-infection. All countries were able to provide the date when the first suspicion of SBV in the herd was reported and nineteen could report the location of the herd at a regional level. This allowed the spread of SBV in Europe to be measured both temporally and spatially. The number of SBV confirmed herds started to increase in December 2011 and two peaks were observed in 2012 (February and May). Confirmed herds continued to be reported in 2012 and into 2013. An increase during winter 2012 and spring 2013 was again observed, but the number of confirmed herds was lower than in the previous year. SBV spread rapidly throughout Europe from the initial area of detection. SBV was detected above the latitude of 60° North, which exceeds the northern expansion observed during the bluetongue virus serotype 8 epidemic in 2006–2009. The impact of SBV was calculated as ratio of the number of herds with at least one malformed SBV positive foetus and the total number of herds in this region. The 75th percentile of the malformations ratio in the various affected countries for the whole reporting period was below 1% and 3% for cattle and sheep herds, respectively. International data collection on emerging diseases represents a challenge as the nature of available data, data quality and the proportion of reported cases may vary widely between affected countries. Surveillance activities on emerging animal diseases are often structured only for case detection making the estimation of infection/diseases prevalence and the investigation of risk factors difficult. The impact of the disease must be determined to allow risk managers to take appropriate decisions. Simple within-herd impact indicators suitable for emerging disease outbreaks should be defined that could be measured as part of routine animal health surveillance programmes and allow for rapid and reliable impact assessment of emerging animal health diseases.  相似文献   
7.
草原毛虫幼虫的食性及其空间格局   总被引:4,自引:1,他引:4  
以禾草及嵩草在高寒草甸中的优势度为指标,研究草原毛虫(Gynaephora alpherakii)的食性、空间格局及其与植物群落的相关性。结果表明:草原毛虫的食性具有较强的选择性,其喜食程度排序为莎草科(Cyperaceae)>禾本科(Gramineae)>杂类草,特别对嵩草属(Kobresia Willd.)植物表现出强烈的偏好和倾向性;草原毛虫的分布型受制于其喜食植物的空间格局,在总体上呈聚集分布,但在小尺度下则常呈均匀分布;虫口密度依赖于喜食植物的丰富度和多样性,随着喜食植物的增加而显著上升,随着植物多样性的减少而显著下降;草原毛虫在高寒草甸生态系统中具有平衡物种关系、调控群落结构的功能;采用定向改变草地植物组成的农艺措施实现对草原毛虫数量的人工调控是实施虫害生态防治的有效途径。  相似文献   
8.
郭亚东  周清  王浩 《安徽农业科学》2012,(36):17801-17804
以湖南农业大学为研究区,根据2005和2010年两期土地利用分类图,利用土地利用类型转移矩阵,结合GIS的空间分析方法,对土地利用结构和空间布局演变进行分析.结果表明,近一半的其他用地按面积比例从大到小依次转变为绿地、道路、娱乐、生活及教学用地.新增教学和娱乐用地分别集中在以修业广场为中心的400m和以老校门为圆心的300 m缓冲区内,新增生活用地呈现南北分化的趋势,新增道路虽较分散但与其余的用地类型毗邻度较高,水域基本不变,而新增绿地面积较大的一片集中在中西部,其余与生活用地的空间演变规律一致.总体来看,土地开发的重点在北部、中部及靠近浏阳河的沿线南端,呈正“S”形格局.未来的校园建设应遵循“科学、生态、人文”的理念,兼顾系统性、关联性和坚持弹性规划的原则对用地布局进行优化.  相似文献   
9.
以四川白河自然保护区连香树为研究对象,采用访问法、样线法和样方法相结合,调查连香树的空间分布位点、种群特征和干扰因素。调查结果表明:保护区有连香树365株,适宜面积约1 995.46 hm2;海拔1 900~2 200 m区域的连香树株数占总株数的89.53%,尤其是海拔2 000~2 100 m分布最为密集(占43.01%);径级分布为纺锤形,自然更新差,种群呈不稳定状态,胸径在12~32 cm之间的有238株(占65.20%)。连香树主要分布区与传统耕作区和放牧区的重叠性高,林地转化成耕地及放牧践踏是连香树种群数量和栖息地下降的主要原因;减少人为干扰、就地保护与监测、建立天然母树园、种子繁殖和扦插是保护连香树种群的有效措施。  相似文献   
10.
The trend in wildlife management over the last two decades has been to develop locally based approaches for responsiveness to local conditions, but some state wildlife agencies are finding the amount of staff time required to service this approach prohibitive. Although local engagement strategies have been lauded as assuring that public trust obligations of state government to citizens are met, we can expect that states with a local focus as their operational level of stakeholder engagement may opt to change their approach to reflect their resource limitations. We argue for comprehensive regional level effort to understand stakeholders augmented with local engagement processes where needed to deal with special circumstances in smaller areas within a region. Such an approach can be anticipated to have implications for stakeholder engagement and human dimensions research needs, which we discuss in the context of public trust resource administration and good governance of wildlife resources.  相似文献   
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