Sustainable or Not? Tourism Development in Agricultural Heritage Sites     

SUN Yehong  SONG Yuxin  CHEN Yuexin  YAO Cancan  LI Wenhua 《资源与生态学报(英文版)》2021,12(4):543-554

Tourism is often considered as one of the dynamic conservation and adaptive management approaches in Agricultural Heritage Sites. It has been over 15 years since the GIAHS programme was initiated in China, and tourism developed quickly in the Agricultural Heritage Sites, to some extent because many researchers consider tourism as a significant engine of the local economy. However, this is contrary to the original intention of agricultural heritage tourism as it was proposed in the first place. Apparently, there are some overt problems during the tourism development process, which are mainly as follows: Some threats to Agricultural Heritage Systems are ubiquitous; The tourism development mode in Agricultural Heritage Sites is questionable; Community involvement is difficult to implement; And the negative environmental impacts are easy to overlook. Under the context of global development, the UNWTO sustainable tourism criteria provide some guidance for agricultural heritage tourism. Based on the Global Sustainable Tourism Criteria, combined with previous survey experiences and related researches, this paper analyzes the tourism sustainability of all the 15 GIAHS sites in China, and explores the current sustainable tourism development level. On this basis, an agricultural heritage sustainable tourism development framework was built in an attempt to find the road to sustainability for agricultural heritage tourism. The framework in the global and local contexts is trying to connect all the important elements related to agricultural heritage tourism according to the UNWTO sustainable tourism criteria.  相似文献   

Characterization and Expression Analysis of Protein Kinase C Gene from Dunaliella salina     

CONG Yuting  MA Yuexin  WANG Yuan  LIU Yiqiong  CHAI Xiaojie 《中国海洋大学学报(英文版)》2019,(4)

Protein kinase C(PKC) has a crucial role in signal transduction for a variety of biologically active substances which activate cellular functions and proliferation. We previously isolated the full-length PKC gene from Dunaliella salina(Ds PKC) using rapid amplification of cDNA ends(RACE) and RT-PCR methods. And we submitted the mRNA sequence of Ds PKC gene to NCBI(Genbank No. JN625213). In the present paper, the Ds PKC gene open reading frame obtained by PCR was cloned into pGS-21 a vector and transformed into Escherichia coli to generate the fusion protein. Bioinformatics analysis revealed that DsPKC gene was a member of serine/threonine kinase with two conserved domains and highly conserved motifs. The Ds PKC was highly expressed upon induction with isopropyl-β-d-thiogalactoside(IPTG) at a final concentration of 0.2 mmol L~(-1) at 37℃. Under salt stress, the fusion protein Green Fluorescent Protein(GFP)-DsPKC was transferred from the cytoplasm to the cell membrane. The expression pattern of Ds PKC gene was analyzed using real-time quantitative PCR, and indicated that Ds PKC gene was up-regulated by 3.0 mol L~(-1) NaCl at 12 h, which was significantly higher than in control values(P 0.05). These results suggest that the Ds PKC gene plays an important role in response to salt stress in D. salina.  相似文献   

早更新世晚期松花江水系袭夺：地球化学和沉积学记录   总被引：2，自引：0，他引：2  

吴鹏  谢远云  康春国  迟云平  魏振宇  王嘉新  张曼  张月馨  刘璐 《地质学报》2020,94(10):3144-3160

水系演化重建是恢复区域构造历史及古环境变化的重要方法。松花江作为中国七大水系之一,其水系演化的相关研究目前还比较薄弱,尤其是第四纪松花江中- 上游是否存在流向反转尚无准确结论。沉积物是河流地质过程的直接产物,是水系演化研究的关键。为此,本研究对哈尔滨荒山钻孔岩芯(HS)进行了磁化率、古地磁和元素地球化学组成分析。结果表明,岩芯62. 3 m(0. 94 Ma B. P. )处,沉积物的岩性、磁化率及元素地球化学组成均发生显著变化。岩芯沉积物岩性在62. 3 m上下发生明显变化,是河流沉积两个沉积旋回的转折点。62. 3 m以下地层的磁化率极低,基本为0,且变化幅度极低,元素地球化学组成则急剧波动,并表现出与现在松花江哈尔滨段下游水系(岔林河、蚂蜒河和牡丹江)相近的地球化学组成;然而,62. 3 m以上地层的磁化率突然升高(99. 673×10-8 m3 kg-1),并具有周期性的高低变化。元素组成呈现稳定的小幅变化,并表现出与拉林河、嫩江和松花江吉林段相近的地球化学组成。0. 94 Ma B. P. 沉积物物源的变化表明河流流向发生了显著变化,松花江中上游河段流向曾在此时发生反转。地球化学记录的水系反转也得到了河流阶地地貌和沉积学证据(砾石的粒径和排列方向)的支持。早更新世早- 中期,以佳- 依分水岭为界,松花江中上游(肇源- 依兰河段)河流自东向西流入松嫩湖盆,松花江下游向东流经三江平原;早更新世晚期,受构造- 地貌- 气候耦合作用的影响,佳- 依分水岭持续抬升,而三江平原一侧不断下沉,佳- 依分水岭两侧河流发生溯源侵蚀,最终导致佳- 依分水岭在0. 94 Ma B. P. 被切穿,松花江中上游水系被下游水系所袭夺,河流流向发生反向,自西向东流经依佳峡谷进入三江平原,现代松花江水系逐渐建立。本研究有助于我们加深对松嫩平原水系演化的理解,为探索东亚水系演化的一致性和区域差异性提供研究证实,同时对松花江流域自然资源禀赋的调查乃至国土空间开发利用具有重要实践意义。  相似文献   

Inhibition of spore germination of Ulva pertusa by the marine bacterium Pseudoalteromonas haloplanktis CI4     

MA Yuexin  LIU Pengliang  ZHANG Yongsheng  CAO Shanmao  LI Dantong  CHEN Wei 《海洋学报(英文版)》2010,29(1):69-78

The e?ect of the bacterial strain CI4 on the germination of spores from the green alga Ulva pertusa was assayed and it was found that the bacterial bioˉlm and cell-free supernatant strongly inhibited spore germination. In attempts to deˉne the chemical nature of the antifouling substance in the supernatant of CI4, the culture supernatants were tested for activity after heat treatment, enzy- matic treatments, size fractionation, and separation into aqueous and organic fractions. Results suggest that this bacterium produces an extracellular component with speciˉc activity toward algal spores that was heat-sensitive and between 3 and 10 kDa in molecular size. The exposure of the organic phase fraction to spores showed inhibitive e?ect on spore germination. Pronase and car- boxypeptidase y did not signiˉcantly a?ect the activity of inhibitory component, suggesting that the component was not a protein or a peptide. The bacterium CI4 was identiˉed as Pseudoalteromonas haloplanktis based on the phenotypic characters and 16S rRNA gene analysis.  相似文献   

丹霞山陡坡上风化洞穴的基本特征及成因探讨     

史月欣  陈留勤  杜丁丁  柴乐  王子涵 《热带地理》2023,43(1):103-114

风化洞穴在全球不同气候区广泛发育,其形成过程和主控因素是地貌学研究的热点问题,但形成机制至今仍存在不少争议,尤其对丹霞地貌区风化洞穴的研究还较少。丹霞山是世界自然遗产地“中国丹霞”的典型代表,陡坡上发育形态和规模各异的风化洞穴,是丹霞地貌的重要景观要素,为认识亚热带湿润气候风化洞穴成因提供了良好的机会。文章以丹霞山砾岩和砂岩陡坡上的5处典型风化洞穴为研究对象,利用野外考察、形态测量、气象监测、样品显微观察及盐化学实验等方法,在已有研究的基础上进一步对湿润气候丹霞地貌区风化洞穴的特征和成因进行探讨。结果表明：1）在砾岩中发育的洞穴一般个体形态较大,洞穴具有较明显的向上和向内生长趋势;砂岩中发育的洞穴大多密集排列,形态较小,常具有蜂巢结构。2）岩石性质是洞穴发育的基本影响因素,在宏观尺度上决定了洞穴的发育位置和排列方式,也决定了不同岩性下发育的风化洞穴的形态特征。在微观尺度上,岩石含有较多长石、钙质胶结物等易溶矿物组分,在酸性雨水渗流过程中发生化学溶解,加上盐结晶作用导致岩石微观结构破坏,诱发洞穴初始形成。3）洞穴尺寸变大后,洞穴内适宜的微气候是洞穴演化的关键因素,为水和盐的聚集及盐风化提...  相似文献   

Effects of Hanseniaspora opuntiae C21 on the growth and digestive enzyme activity of juvenile sea cucumber Apostichopus japonicas     

马悦欣  刘志明  杨志平  包鹏云  张丛尧  丁鉴锋 《中国海洋湖沼学报》2014,32(4):743-748

The effects of a diet containing Hanseniaspora opuntiae C21 on growth and digestive enzyme activity were estimated in juvenile Apostichopus japonicus. Groups of sea cucumbers were fed diets containing H. opuntiae C21 at 0(control), 10 4, 10 5, and 10 6 CFU(colony-forming units)/g feed. Results showed that after 45 d the specific growth rate(SGR) of sea cucumbers fed a C21-supplemented diet at 10 4 CFU/g feed was significantly higher than that of the control( P 0.05). Intestinal trypsin and lipase activities were significantly enhanced by C21 administration at 10 4 and 10 5 CFU/g feed compared with the control( P 0.05). After feeding for 23–42 d, C21 was demonstrated by denaturing gradient gel electrophoresis to be present in the intestine of sea cucumbers. In addition, after feeding the C21-supplemented diets for 15 d, the sea cucumbers were switched to an unsupplemented diet and C21 was confirmed to be capable of colonizing the intestine for at least 31 d after cessation of feeding. In conclusion, C21 was shown to successfully colonize the intestine of juvenile A. japonicus via dietary supplementation, and improve growth and digestive enzyme activity.  相似文献   

Revisiting the Concentration Observations and Source Apportionment of Atmospheric Ammonia     

Yuepeng PAN  Mengna GU  Yuexin HE  Dianming WU  Chunyan LIU  Linlin SONG  Shili TIAN  Xuemei Lü  Yang SUN  Tao SONG  Wendell W. WALTERS  Xuejun LIU  Nicholas A. MARTIN  Qianqian ZHANG  Yunting FANG  Valerio FERRACCI  Yuesi WANG 《大气科学进展》2020,37(9):933-938

正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on  相似文献   

人地耦合视角下中国自然保护地有效性评估研究进展与展望     

于超月  高阳  王晨旭  刘悦忻 《地理科学进展》2022,41(11):2178-2190

自然保护地有效性评估是测度其管护效果并提出改进意见的重要手段。论文从人地耦合的视角出发,提出了自然保护地有效性评估不同阶段对应的目标层次。在此基础上,分析了有效管理理论、景观可持续理论和社会—生态网络理论在指导自然保护地有效性评估中的作用。依据不同阶段的目标层次,系统地梳理了中国自然保护地有效性评估现状,并提出了提升社区治理在评估体系中的重要性、从生物多样性保护转向兼顾人类福祉提升的评估、探究管理工作对自然保护地有效性的作用机制、推动自然保护地监测网络与数据平台建设等未来研究趋势,从而完善人地耦合视角下的自然保护地有效性评估路径,以期改善自然保护地有效性评估的时效性、全面性与合理性,促进人与自然的和谐共生。  相似文献   

Purification and characterization of novel κ-carrageenase from marine Tamlana sp. HC4     

孙飞雪  马悦欣  王颖  刘倩 《中国海洋湖沼学报》2010,28(6):1139-1145

We isolated a bacterial strain (HC4) that is able to degrade κ-carrageenan from a live specimen of the red alga Hyalosiphonia caespitosa. With 16S rRNA gene sequencing, we identified the strain as Tamlana sp., and then purified an extracellular κ-carrageenase from a culture of Tamlana sp. HC4 by ammonium sulfate precipitation, Sephadex G-200 gel filtration chromatography, and DE-cellulose 52 anion-exchange chromatography. The purified enzyme yields a single band on SDS-PAGE with a molecular mass of 66.4 kDa. The optimal pH and temperature for κ-carrageenase activity are at 8.0 and 30°C, respectively. The enzyme is stable over the range of pH 7.2–8.6 below 45°C. The enzyme activity is strongly inhibited by Zn²⁺ and Cu²⁺ at 1 mmol/L. The enzyme-catalyzed reaction follows Michaelis-Menten kinetics with the Michaelis constant (K _m ) at 7.63 mg/ml. Analysis of the degradation products of the κ-carrageenase by ESI-MS and ¹³C-NMR spectroscopy indicates that the enzyme degrades κ-carrageenan down to the level of κ-neocarrabiose sulfate.  相似文献   

1985―2010年中国沿海城市人口密度时空变化     

符跃鑫  陈影影  张振克 《热带地理》2014,34(5):635-642

基于1985―2010年沿海城市人口密度数据,利用ArcGIS和空间统计的方法,分析了1985、1990、1995、2000、2005和2010年6个时间节点沿海城市人口密度的时空变化特征,并探讨了沿海城市人口密度变化的驱动因素。结果表明：1985年以来中国沿海城市人口密度整体上呈现不断增长的趋势,2010年沿海城市常住人口总数为2.64亿人,约占全国总人口的19.70%,平均人口密度在640人/km2左右。人口空间分布差异明显,集中表现为区域中心城市人口密度大,南通市以北地区大部分沿海城市的人口密度小于南通市以南的沿海城市。自然因素、经济因素、城市地位与功能、国家政策以及城市发展历史等是沿海城市人口密度差异的主要驱动因素,其中人口迁入已成为影响人口密度时空变化的最重要驱动力。为进一步促进沿海城市人口的合理分布,建议加强引导沿海地区人口有序流动,积极发展中小城镇,注重提高环境的承载力,促进人口、资源与环境的可持续发展。  相似文献