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361.
高强度人类活动对泉州湾滨海湿地环境的影响及其对策 总被引:3,自引:2,他引:1
由于滨海湿地丰富的资源和优越的环境,人们对其进行了大规模的开发利用,导致了滨海湿地的丧失与生态退化。滨海湿地位于陆地-海洋-大气相互作用最活跃的地带,具有非常重要的生态意义。总结泉州湾滨海湿地水动力、地貌、生态、环境质量的特征,分析围填海、养殖、污染物排放及人工生态工程等对滨海湿地的影响。结果表明,随着社会经济的快速发展以及人类活动的显著增强,泉州湾滨海湿地面积减小,输水及输沙的路径和方式发生变化,湿地环境质量显著下降,生物多样性及生物量减少。为了实现泉州湾滨海湿地的可持续发展,提出了如下对策:(1)加强围海造地的科学管理,提倡新的围海造地方式;(2)开展海岸整治与生态修复,建设特色湿地公园;(3)挖掘海洋文化特色,发展生态旅游。本研究揭示高强度人类活动对滨海湿地环境的影响,为开展滨海湿地研究、整治与修复,为制定滨海湿地开发利用与保护对策提供科学依据。 相似文献
362.
City lights, fishing boats, and oil fields are the major sources of nighttime lights, therefore the nighttime light images provide a unique source to map human beings and their activities from outer space. While most of the scholars focused on application of nighttime light remote sensing in urbanization and regional development, the actual fields are much wider. This paper summarized the applications of nighttime light remote sensing into fields such as the estimation of socioeconomic parameters, monitoring urbanization, evaluation of important events, analyzing light pollution, fishery, etc. For estimation of socioeconomic parameters, the most promising progress is that Gross Domestic Product and its growth rate have been estimated with statistical data and nighttime light data using econometric models. For monitoring urbanization, urban area and its dynamics can be extracted using different classification methods, and spatial analysis has been employed to map urban agglomeration. As sharp changes of nighttime light are associated with important socioeconomic events, the images have been used to evaluate humanitarian disasters, especially in the current Syrian and Iraqi wars. Light pollution is another hotspot of nighttime light application, as the night light is related to some diseases and abnormal behavior of animals, and the nighttime light images can provide light pollution information on large scales so that it is much easier to analyze the effects of light pollutions. In each field, we listed typical cases of the applications. At last, future studies of nighttime light remote sensing have been predicted. 相似文献
363.
Ziliang Zhao Yang Xu Feng Lu Jie Chen Ling Yin 《International journal of geographical information science》2016,30(9):1738-1762
ABSTRACTIn recent years, call detail records (CDRs) have been widely used in human mobility research. Although CDRs are originally collected for billing purposes, the vast amount of digital footprints generated by calling and texting activities provide useful insights into population movement. However, can we fully trust CDRs given the uneven distribution of people’s phone communication activities in space and time? In this article, we investigate this issue using a mobile phone location dataset collected from over one million subscribers in Shanghai, China. It includes CDRs (~27%) plus other cellphone-related logs (e.g., tower pings, cellular handovers) generated in a workday. We extract all CDRs into a separate dataset in order to compare human mobility patterns derived from CDRs vs. from the complete dataset. From an individual perspective, the effectiveness of CDRs in estimating three frequently used mobility indicators is evaluated. We find that CDRs tend to underestimate the total travel distance and the movement entropy, while they can provide a good estimate to the radius of gyration. In addition, we observe that the level of deviation is related to the ratio of CDRs in an individual’s trajectory. From a collective perspective, we compare the outcomes of these two datasets in terms of the distance decay effect and urban community detection. The major differences are closely related to the habit of mobile phone usage in space and time. We believe that the event-triggered nature of CDRs does introduce a certain degree of bias in human mobility research and we suggest that researchers use caution to interpret results derived from CDR data. 相似文献
364.
青藏高原海拔4000 m区域人类活动的新证据 总被引:2,自引:0,他引:2
青藏高原早期人类活动对于研究人类对极端环境响应与适应至关重要,4000 m海拔区域是人类向高原腹地迁移与扩散的关键。下大武1号遗址(XDW1)发现了11290±69 cal. a BP人类活动遗留的灰烬层,及其年代主要集中在11.2 cal. ka BP的细石叶、石片等石制品,是目前青藏高原4000 m海拔区域发现的最早的人类活动证据之一,说明在全新世伊始,人类就已经登上了海拔4000 m的青藏高原主体。据此推测人类在高原东北部扩张的时空演变过程,末次冰消期人类在海拔3000~4000 m高原东北缘青海湖盆地、共和盆地等区域活动,全新世初期扩张至4000 m海拔高原主体,全新世大暖期向高原腹地深入;上述3个人类活动阶段与末次冰消期环境的改善、全新世伊始的气候迅速转暖和全新世暖期盛期的到来等重大气候变化阶段密切相关。 相似文献
365.
通过对澧阳平原野外调查,多剖面地层对比分析及岩板垱(YBD)剖面样品的粒度、地球化学元素分析和年代测定,揭示该区晚更新世晚期至全新世早中期环境演变,并探讨其对人类活动的影响。研究结果表明,30~6 ka B.P.间,澧阳平原由冲沟发育的黄土台地向河湖发育的平原丘岗地貌过渡;气候环境经历了弱暖湿-气候变差-凉湿-波动回暖-暖湿的变化;更新世末至全新世早期稻作农业的出现与该区的环境条件和文化基础密切相关;环境演变也推动了古人类活动范围和聚落特征的变化。 相似文献
366.
以长株潭主城区为研究对象,综合考虑卫星遥感数据、土地利用数据以及地理国情普查数据特点建立长株潭用地类型分类系统,应用土地利用转移矩阵和景观人为干扰测度模型获取主城区用地转移矩阵和人为干扰度指数时空分布,探讨长株潭主城区生态景观与人为干扰之间的关系。结果表明:从土地利用变化角度,1978—2015年长株潭主城区耕地、园林地、建设用地发生了显著变化,耕地总体上呈持续下降趋势,从3 544.67 km~2下降到2 571.18 km~2,园林地呈现先下降后升高的变化趋势,总体下降177.89 km~2;建设用地呈持续上升趋势,从80.56 km~2增加到1 252.85 km~2;在1994—2000年和2010—2015年长株潭主城区土地利用变化两个典型阶段,建设用地的增加主要通过占用耕地和园林地的方式实现。景观人为干扰指数时空分析表明:1978—2015年长株潭主城区景观人为干扰指数高值区主要集中在中心城市和其周边地区,在人类活动的影响下,中心城区以耕地、园林地向建设用地转移为主,周边地区主要以耕地和园林地的相互转移为主;随着城市化进程持续加快,人类活动对主城区生态景观的影响总体呈加强趋势,且受人类活动干扰主要集中在中心城区。 相似文献
367.
Congbin FU 《大气科学进展》2017,34(10):1159-1168
To commemorate 100 years since the birth of Professor Duzheng YE, this paper reviews the contribution of Ye and his research team to the development from climate to global change science in the past 30 or so years, including:(1) the role of climate change in global change;(2) the critical time scales and predictability of global change;(3) the sensitive regions of global change—transitional zones of climate and ecosystems; and(4) orderly human activities and adaptation to global change, with a focus on the development of a proactive strategy for adaptation to such change. 相似文献
368.
Do perceptions of the Red‐tailed Hawk indicate a human‐wildlife conflict on the island of La Gonave,Haiti?
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Justin White Lisa M. Kennedy Maria Elisa Christie 《Singapore journal of tropical geography》2017,38(2):258-268
The Caribbean subspecies of the Red‐tailed Hawk (Buteo jamaicensis solitudinus or B.j. jamaicensis) is the largest native carnivore on the island of La Gonave, Haiti, and the island's apex predator. On other Caribbean islands, raptors have been persecuted by local people typically because of their depredation of livestock. In addition to possible persecution from humans, Red‐tailed Hawks on La Gonave face challenges from island‐wide timber overharvest and rapid land‐cover changes. To better understand the human‐apex predator relationship on La Gonave, we surveyed islanders about their perceptions of, and interactions with, the Red‐tailed Hawk. According to 121 respondents from 10 villages, La Gonavans do not hunt, kill, or consume Red‐tailed Hawks. Our study revealed a notable absence of negative perceptions of the hawk by respondents despite intense hawk depredation of domestic chickens. While the chicken depredation may lead outside observers to consider the human‐hawk relationship on La Gonave as representative of a human‐wildlife conflict, our interview data do not support that conception. Our findings reflect an important conversation in related contemporary scientific literature about what constitutes human‐wildlife conflicts across various cultures. Despite tolerance by residents, Red‐tailed Hawks on La Gonave remain threatened by habitat degradation. 相似文献
369.
370.
48年来黄河入海水沙过程及其对流域人类活动的响应 总被引:3,自引:0,他引:3
黄河下游入海水沙现今出现急剧减少的趋势.水沙的季节性变化影响着年内的径流量、输沙量的分配情况.这种变化的影响因素有自然因素和人为因素两方面,而后者占主要地位.水沙的锐减对河口生态环境的变化有着负面影响.黄河干流已建成的大中型水库尤其是龙羊峡水库对入海水沙起着负面作用. 相似文献