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21.
庭园是形成和保存农业生物多样性的基本单位,也是野生植物和栽培植物聚集的场所。在农村,庭园的主要作用是提供日常生活所需,还可产生收入。庭园中不仅存在较高的生物多样性,而且庭园也有很多社会、文化、生态方面等功能。该研究针对通辽市库伦旗芒汗苏木毛敦塔拉嘎查蒙古族,采用随机抽样和农户推荐的方式选择了11个农户,以农户的整个庭园面积为样方,设立11个样方进行农业生物多样性分析,并用漫谈式访谈和半结构调查方法进行庭园植物及其经济效益调查。结果表明:毛敦塔拉嘎查蒙古族庭园植物物种丰富度较高,庭园植物共有96种,包括栽培及野生的植物蔬菜类33种、水果用19种、观赏用20种、饲料用8种、药食兼用5种、其它用途类16种,其中有些种类具有多种用途;毛敦塔拉嘎查各农户庭园植物的多样性随着庭园类型及庭园管理者的特征而不同;庭园面积大且种植大量经济作物的庭园经济效益高;据调查当地庭园的经营模式具有生态种植型、综合经营型、庭园养殖型三种类型。这些庭园植物不仅对当地农牧民的生活具有广泛作用而且对农业生物多样性保护具有深远意义。  相似文献   
22.
靳程  杨永川  周礼华  龙宇潇  陈媛 《广西植物》2023,43(8):1437-1445
金钱松是中国最具国际影响力的古老孑遗植物之一,其面临生境破碎化、种群分散以及个体数量减少的种种威胁。幸运的是,已有研究指出村落风水林为金钱松自然种群提供了庇护,然而,村落风水林到底如何发挥保护效用,尚待深入探索。因此,该研究通过野外调查和社区访谈的方法对所有金钱松自然种群的更新现状、保护行为和干扰程度进行全面调查,并以林家塘村金钱松自然种群为例揭示金钱松村落风水林保护和管理模式。结果表明:(1)相较于其他生境类型,村落风水林生境中金钱松自然种群径级结构连续,幼苗密度较高;(2)水口林、墓地林和阳基树承载的风水与禁忌文化是村落风水林能够有效保护金钱松自然种群的内在原因;(3)新时代乡村旅游业的发展进一步促进了村民对金钱松村落风水林的保护。综上所述,在乡村振兴背景下,基于风水和禁忌文化的村落风水林保护和管理模式是金钱松自然种群保护的绝佳模式。  相似文献   
23.
ABSTRACT

In remote villages of the Eastern Highlands of Papua New Guinea, where official village courts and other state institutions are absent, local leaders routinely hold unofficial village courts to maintain law and order. They base their decisions on local perceptions of order and justice, all the while emulating elements of state justice and constantly referring to the state as the source of their legitimacy. As these unofficial judicial institutions historically emerged as a convergence of local patterns of leadership with colonial concepts of order, they neither form a completely new nor completely autochthonous method of conflict settlement, but are an example of para-statehood, in which local leaders take on state functions in the absence of the state.  相似文献   
24.
LETTERS     
《Ostrich》2013,84(3):223-224
We used video recordings to perform a behavioural analysis of a Village Weaver Ploceus cucullatus colony in Awash National Park, Ethiopia. We focused specifically on female behaviour during the pair-formation, egg-laying and early-incubation phases of the nesting cycle. A factor analysis revealed that females’ temporal investments can be partitioned into three broad behavioural categories: (1) behaviours associated with aggression, (2) time away/ inside nest, and (3) behaviours associated with copulation. Time budgets revealed females spent approximately 61% of their time away from the colony and 38% of their time inside their nests. The performance of individual behaviours was largely a function of temporal and social factors, including when the birds were observed and the personality of the territorial male. Females invested more time away from the nest earlier and more time inside the nest later in the observation period. One aspect of a territorial male’s personality, boldness, was a predictor of several female behaviours: a female Village Weaver was significantly more likely to remain on a territory if the resident male had a tendency not to flee during colony-wide disturbances. Lastly, a path analysis revealed that females exhibited consistent sequential patterns of behaviour.  相似文献   
25.
Haemoparasitic infections in wild birds have been widely studied in order to understand parasite–host relation- ships, but our understanding of their impact on the host's fitness is still limited. In this study, we quantified the associations between microfilarial infections and body mass and between microfilarial infections and haemato- crit values in Village Weavers Ploceus cucullatus. We screened blood samples (thin smear and buffy coat) for the presence of haemoparasitic infections and measured haematocrit values. Fifty-seven percent of 91 individuals screened carried a microfilarial infection but, contrary to expectations, no other haemoparasitic infections were detected in the blood samples. We found a negative relationship between microfilarial infection status and body mass, but no relationship between infection status and haematocrit values. Our results suggest that microfilarial infections may be associated with body mass loss in wild birds.  相似文献   
26.
选取与乡村人居林关系最为密切的林木覆盖指数、林木结构指数、林网密度指数、林木健康指数和林木稳定指数指标,利用层次分析法确定权重系数,通过间接构建评价指标各要素占评价区域加权面积比重的方法,进行乡村人居林质量评价,结果表明,4个代表型村庄人居林建设质量差异较大,以南书村为最好,上浦村和扁山村其次,茜黄村最差,综合评价得分分别为75.7972分、52.7972分、41.5418分和9.7689分.这种评价方法科学有效、简单快速,实用性强,避免了传统评价方法基础数据获取困难和可操作性不强的缺陷,为乡村人居林质量评价提供依据.  相似文献   
27.
The present study is to investigate the antitumor, antioxidant and antibacterial potential of silver nanoparticles (Ag NPs) synthesized from a phenolic derivative 4-N-methyl benzoic acid, isolated from a medicinal plant (Memecylon umbellatum Burm F). The Bio-inspired nanoparticles (NPs) were analyzed by using UV–vis spectroscopy, FTIR, HRTEM, Zeta potential and XRD techniques. The UV–vis spectroscopy study at the band of 430 nm confirmed the nanoparticles formation. HRTEM report showed that the AgNPs synthesized were in the size range 7–23 nm. The harvested nanoparticles were subjected to anti-bacterial assay and a dose dependent inhibitory action was observed against the tested human pathogens. Among the tested bacteria, Acinetobacter baumannii was found to be highly sensitive to AgNPs (diameter of zone of inhibition was 31 mm). Further, the silver nanoparticles exhibited a good anti-tumor activity against the breast cancer cell line (MCF 7) with an IC50 value of 42.19 µg/mL. As the present study confirmed a good antibacterial, antioxidant and antitumor activity in the nanoparticles synthesized using 4-N-methyl benzoic acid derived from a medicinal plant, the product can be further tested to formulate a good lead compound for biomedical applications.  相似文献   
28.
基于高分辨率卫星图的川中丘陵区村级景观格局特征研究   总被引:7,自引:0,他引:7  
以Erle C.Ellis 建立的村级景观分类和景观制图方法,利用IKONOS高分辨率(1 m)卫星遥感图,进行典型抽样和地形→土地利用→土地覆被→生态立地的景观分类和分层制图,研究了四川盆地中部丘陵地区村级景观的构成和格局特征,并就有关方法作了讨论.结果表明,川中盆地丘陵村级景观类型多样,其多样性指数从地形、土地覆被、土地利用到生态立地变化在1.08~2.26之间,丰富度除土地覆被较高,达到85%以外,其余都较低,在42.22%~58.62%之间.分布普遍的生态立地类型为12.5%,其余88.5%的类型都以较大差异分布在各村级景观内.景观破碎化指数较高,不同村级景观之间为2.93~4.27,地形到生态立地的破碎度为2.86~5.63.村级景观构成中,人口密度、道路面积和农家院落面积与景观格局指数存在较大程度的线性相关关系,但以农家院落面积与景观分形指数、景观破碎度的线性相关显著,分别为0.957*和0.991**.运用景观4级分类和制图方法研究村级景观,多数景观格局指标都表现出显著的统计学差异,表明运用高分辨率卫星遥感图研究村级景观,以多级景观单元分类研究比单一分类的更能够反映相关信息,增加对村级景观格局的认识和理解.  相似文献   
29.
Conceptual issues of gender equity in development are examined and analyzed with respect to the Social forestry project (Village and Farm Forestry Project; VFFP) as a means to redistribute access to productive resources and household benefits. A random sample of 120 VFFP participants, both men and women, was interviewed regarding their division of labor and their access to resources and benefits in relation to the project. The survey suggests that women and men produce different quantities and types of labor for the VFFP. Although women supply more labor than men, it is possible that women's overall labor burden is reduced in relation to the national average. For VFFP participants called core farmers, women enjoy the same access to productive resources and services as men, with the important exception that women do not generally have land rights. Yet 100% of interviewed women core farmers answered positively to six indicators of sociocultural advancement because of their participation in the VFFP. Among a second tier of VFFP participants called participating farmers, a large majority of women respondents claim rights on most resources and services important in the VFFP, although these proportions are less than among men respondents. Most women participating farmers answered affirmatively to the six indicators of sociocultural advancement, but in lesser proportions than among women core farmers.  相似文献   
30.
乡村生态学概论   总被引:10,自引:0,他引:10  
城市生态学已逐渐发展成一门受众人肯定的生态学分支学科,但乡村生态学未引起广泛重视。本文定义乡村生态学为研究村落形态、结构、行为及其与环境本底统一体客观存在的生态学分支科学。村落是以一定年龄结构、一定数量人口或人群为基本特征,以户为组成单位,以土地为经营对象,以相应的生物(牲畜和作物)为主要价值资源的人类聚居的空间单元。村落除具空间和生命涵义外,还直接联系地理位置、地形地势、气候、土壤和植被等景观要素与资源参数;同时,它还与历史传统、社会习俗等多方面复杂因素有关。乡村生态学的意义在于揭示村落与所有这些相关因素的关系,并用以指导乡村建设。  相似文献   
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