Jiuzhaigou National Nature Reserve Research Articles

New diatom species Diploneis zhui sp. nov. from Jiuzhaigou National Nature Reserve, China

Diploneis zhui sp. nov. was observed in epilitic diatom communities from Jiuzhaigou National Nature Reserve. The species is described herein based on light microscopy (LM) and scanning electron microscopy (SEM) and ecological information of the type locality is provided. The species is characterized by linear to linear-elliptic valves with broadly rounded ends, 18–39 μm long, and 9.5–11.0 μm wide and partly biseriate striae, 16–18 in 10 μm. The species is compared with most similar taxa from other regions. The discovery of a new diatom species confirms the importance of Jiuzhaigou not only in terms of species richness and endemicity, but also for the biodiversity of freshwater karst ecosystems.

Sellaphora jiuzhaienis sp. nov. (Bacillariophyceae)—A new diatom species from Jiuzhaigou National Nature Reserve, China

A new species Sellaphora jiuzhaienis sp. nov. was found in epilithic samples from Jiuzhaigou National Nature Reserve, China. The species is described herein as new to science based on light microscopy (LM) and scanning electron microscopy (SEM), and ecological information is provided. The species has linear to linear-elliptic valves, 17.5–33.5 μm long and 7.0–8.5 μm wide and very broad conopeum that occupies almost half of the valve width. The discovery of a new diatom species confirms the importance of Jiuzhaigou not only in terms of species richness and endemicity but also for the biodiversity of freshwater karst ecosystems in the national protected areas of China.

Age Structure and Body Size of the Plateau Brown Frog (Rana kukunoris) in the Jiuzhaigou National Nature Reserve and Potential Climatic Impacts on Its Life History Variations

Jiuzhaigou National Nature Reserve (JNNR) is a renowned World Biosphere Reserve and UNESCO-designated World Nature Heritage Site. The age structure and body size of a population are crucial for assessing the quality of habitats in which a population lives and are essential for the vertebrate conservation and management, especially for amphibians. Unfortunately, information about the life history traits of amphibians is currently unavailable in JNNR. Herein, we first estimated the age structure and body size of Rana kukunoris, which is endemic to the Eastern Qinghai-Xizang Plateau. Then, we compared our data with 28 reported populations along an elevation gradient (1797–3450 m) and investigated how life history traits respond to climatic variations. Our results indicated the following: (1) For individuals from JNNR, the maximum longevity is 8 years, age at sexual maturity (ASM) is 2 years, suggesting a favorable ecological environment in JNNR. Notably, females are significantly larger than males due to the age factor. (2) The average age and ASM show a positive correlation with elevation. However, when the elevation exceeds 3000 m, the average SVL initially increases and then decreases due to the harsh environmental conditions at higher elevation. (3) Temperature and/or UV-B have a significant impact on the average age, ASM, and average SVL variations of R. kukunoris, suggesting adaptive potential of this species via life history variations in light of environmental changes. These accounts provide antecedent information about the life history traits of amphibians in JNNR, and provide insights into the driving factors of the life history variations of the plateau brown frog.

Bacterial Communities Associated with Tufa Deposits and Characterization of Indigenous Calcifying Bacterial Isolates from Jiuzhaigou National Nature Reserve, Sichuan, China

Tufa is a common calcium carbonate deposit in karst landscapes and microbes may play an important role in its formation. As an important natural resource treasure trove, the diversity of bacteria from the Jiuzhaigou National Nature Reserve tufa deposits and their potential to deposit carbonates are still unknown. In this study, 16S rRNA gene sequencing technology was used to assess the bacterial community composition of Pearl Shoal in Jiuzhaigou National Nature Reserve. The results showed that the main dominant phyla were Proteobacteria, Cyanobacteria, Bacteroidetes and Actinobacteria. With the gradual increase of flow rate, the bacterial community structure was gradually simplified and the dominant phylum changed. The community structure of different sampling sites was significantly different. Besides, 17 strains capable of precipitating calcium carbonate were isolated using microbiological methods. The two strains with relatively strong calcium-forming properties were identified as Leucobacter sp. (J1) and Brucella sp. (J2), respectively. Both strains were able to elevate the environmental pH and produce extracellular polymeric substance (EPS). However, Leucobacter sp. (J1) formed calcite crystals with spherical structure, whereas Brucella sp. (J2) formed the rhombohedral and some spherical calcite crystals, evidence for strain-specific characteristics. It is the first research to provide information regarding the diversity of bacterial communities associated with tufa deposits and the characterization of calcifying bacteria isolated from Jiuzhaigou National Nature Reserve.

Declining tree growth rates despite increasing water-use efficiency under elevated CO2 reveals a possible global overestimation of CO2 fertilization effect

Though rising atmospheric CO2 concentrations (Ca) harm the environment and society, they may also raise photosynthetic rates and enhance intrinsic water-use efficiency (iWUE). Numerous short-term studies have investigated tree growth under elevated CO2 (eCO2) conditions, but no long-duration study has investigated eCO2 impacts on tree growth and iWUE under natural conditions. Utilizing a new dendrochronological experimental design in a heavily-touristed nature preserve in Southwest China (Jiuzhaigou National Nature Reserve), we compared tree growth (e.g., basal area increment) and iWUE in two biophysically and environmentally similar valleys with contrasting anthropogenic activities. Trees in the control valley with ambient CO2 benefited from increasing Ca, possibly due to the CO2 fertilization effect and optimal environmental conditions. However, trees in the treatment valley with intensive tourism experienced comparatively higher localized eCO2 and growth rate declines. While iWUE increased (1959–2017) in the control (25.3%) and treatment sites (47.8%), declining tree growth rates in the treatment site was likely because comparatively extreme CO2 exposure levels encouraged stomatal closures. As the first long-term study investigating eCO2 impacts on tree growth and iWUE under natural conditions, we demonstrate that increased forest iWUE is unlikely to overcome negative drought stress and rising temperature impacts. Thus, forest potential for mitigating eCO2 and global climate change is likely overestimated, particularly under dry temperate conditions.

Exploring cryptic biodiversity in a world heritage site: a new pitviper (Squamata, Viperidae, Crotalinae) from Jiuzhaigou, Aba, Sichuan, China.

This study presents a comprehensive morphological comparison along with molecular phylogeny of the genus Gloydius based on five mitochondrial genes (12S, 16S, COI, cytb, and ND4). The specimens collected from Jiuzhaigou National Nature Reserve are shown to be a new species, Gloydiuslateralis sp. nov. Zhang, Shi, Jiang & Shi based on a combination of morphological and molecular accounts. G.lateralis sp. nov. differs from other congeneric species by a series of diagnostic morphological characteristics and forms a strongly supported monophyletic group. The new species is phylogenetically closely related to G.swild, another recently described species from Heishui, Aba, Sichuan.

Estimation of Aboveground Vegetation Water Storage in Natural Forests in Jiuzhaigou National Nature Reserve of China Using Machine Learning and the Combination of Landsat 8 and Sentinel-2 Data

Aboveground vegetation water storage (AVWS) is a fundamental ecological parameter of terrestrial ecosystems which participates in plant metabolism, nutrient and sugar transport, and maintains the integrity of the hydraulic system of the plant. The Jiuzhaigou National Nature Reserve (JNNR) is located in the Eastern Tibet Plateau and it is very sensitive to climate change. However, a regional estimate of the AVWS based on observations is still lacking in the JNNR and improving the model accuracy in such mountainous areas is challenging. Therefore, in this study, we combined the Landsat 8 and Sentinel-2 data to estimate AVWS using multivariate adaptive regression splines (MARS), random forest (RF) and extreme gradient boosting (XGBoost) with the linkage of 54 field observations in the JNNR. The results showed that AVWS varied among different forest types. The coniferous forests had the highest AVWS (212.29 ± 84.43 Mg ha−1), followed by mixed forests (166.29 ± 72.73 Mg ha−1) and broadleaf forests (142.60 ± 46.36 Mg ha−1). The average AVWS was 171.2 Mg ha−1. Regardless of the modelling approaches, both Sentinel-2 and Landsat 8 successfully estimated AVWS separately. Prediction accuracy of AVWS was improved by combining Landsat 8 and Sentinel-2 images. Among the three machine learning approaches, the XGBoost model performed best with a model efficiency of 0.57 and root mean square error of 48 Mg ha−1. Predicted AVWS using XGBoost showed a strong spatial pattern of across the study area. The total AVWS was 5.24 × 106 Mg with 67.2% coming from conifer forests. The results highlight the potential of improving the accuracy of AVWS estimation by integrating different optical images and using machine learning approaches in mountainous areas.

Lessons of government centralization and credibility: A qualitative case-study of administrative change in Jiuzhaigou Nature Reserve, China (1982–2018)

How to ensure adequate provision of public services in protected area management is a well-known debate. By using the credibility thesis as a theoretical and methodological tool, this paper furnishes a renewed look at how administrative changes affect the provision of public services. For this purpose, a detailed case-study is presented: the Jiuzhaigou National Nature Reserve in China. The analysis covers a period of 36 years (1982–2018) of administrative change in the protected area. It will be ascertained that the levels of administration for the reserve kept increasing, along with continuous changes in the corresponding government structure. The latter became increasingly centralized, leading to significant stagnation of the government at the “form” level and subsequent failure at the “function” level. Problems culminated in 2013 as large-scale social protests erupted, after which local villagers took matters into their own hands and single-handedly developed a rural development plan, which eventually received approval from the authorities. This detailed study shows that to overcome the deficiencies of a stalled governance system and improve credibility, the specific form of institutions – a centralized or decentralized administration – is of secondary importance as compared to the establishment and implementation of unambiguous policies, along with increased local participation, and transparent distribution of management responsibilities and authority.

Machine learning-based estimates of aboveground biomass of subalpine forests using Landsat 8 OLI and Sentinel-2B images in the Jiuzhaigou National Nature Reserve, Eastern Tibet Plateau

Machine learning-based estimates of aboveground biomass of subalpine forests using Landsat 8 OLI and Sentinel-2B images in the Jiuzhaigou National Nature Reserve, Eastern Tibet Plateau

Modeling the Relationships between the Height and Spectrum of Submerged Tufa Barrage Using UAV-Derived Geometric Bathymetry and Digital Orthoimages.

Tufa barrages play an important role in fluviatile tufa ecosystems and sedimentary records. Quantifying the height of tufa barrage is significant for understanding the evolution and development of the Holocene tufa barrage systems. However, for submerged tufa barrages, there is no low-cost non-contact method to retrieve barrage height. Generally, it is difficult to recognize small tufa barrages by means of remotely sensed satellite data, but the combination of unmanned aerial vehicles (UAV) and Structure-from-Motion (SfM) photogrammetry makes it possible. In this study, we used a fixed-wing UAV and a consumer-grade camera to acquire images of the submerged tufa barrage in Lying Dragon Lake, Jiuzhaigou National Nature Reserve, China, and estimated the height of the tufa barrage through UAV-based photogrammetric bathymetry. On this foundation, the relationship between barrage height and its spectrum was established through band ratio analysis using UAV-derived geometric bathymetry and digital orthoimages, which provided an alternative strategy to characterize the height of submerged tufa barrages. However, the spectral characteristics of submerged tufa barrages will oscillate with changes in the environmental conditions. In future research, we will consider using a dedicated aquatic multispectral camera to improve the experimentation.

Predicting the responses of subalpine forest landscape dynamics to climate change on the eastern Tibetan Plateau.

Subalpine vegetation across the Tibetan Plateau is globally one of the most sensitive to climate change. However, the potential landscape-scale effects of climate change on subalpine forest dynamics remain largely unexplored. Here, we used a forest landscape model (LANDIS-II) coupled with a forest ecosystem process model (PnET-II) to simulate forest dynamics under future climate change in Jiuzhaigou National Nature Reserve in the eastern subalpine region of the Tibetan Plateau. We examined changes in the composition, distribution and aboveground biomass of cold temperate coniferous forests, temperate coniferous forests, deciduous broad-leaved forests and redwood forest under four climate change scenarios (RCP2.6, RCP4.5, RCP8.5 and the current climate) from 2016 to 2096. Our model predicts that by 2096, (i) cold temperate coniferous forests will expand and increase by 7.92%, 8.18%, 8.65% and 7.02% under current climate, RCP2.6, RCP4.5 and RCP8.5scenarios, respectively; (ii) distribution of forests as a whole shows upward elevational range shift, especially under RCP8.5scenario and (iii) total aboveground biomass slowly increases at first and then decreases to 12%-16% of current distribution under RCPs. These results show that climate change can be expected to significantly influence forest composition, distribution and aboveground biomass in the subalpine forests of eastern Tibetan Plateau. This study is the first to simulate forest dynamics at the landscape scale in subalpine areas of the Tibetan Plateau, which provides an important step in developing more effective strategies of forest management for expected climate change, not only in China but also around the world.

九寨沟自然保护区生态安全动态评价及障碍因子

生态安全是国家安全体系的重要基石，自然保护区在涵养水源、维持生态平衡等方面发挥着重要作用，可有效缓解社会快速发展对自然环境的破坏，是维持区域生物多样性的重要安全屏障。九寨沟自然保护区地处生态脆弱敏感区，在自然灾害和人类活动叠加影响下的生态安全状况备受各界关注。基于此，采用PSR模型和障碍因子分析法，从资源环境、人类活动、社会经济等方面选取23项指标构建评价体系，综合评价九寨沟保护区20年来的生态安全动态变化，探明主要影响因素。研究表明：（1）2001-2019年九寨沟生态安全指数呈曲折上升趋势，从0.7933增加至0.8623，其中压力和状态安全指数呈波动下降趋势，响应指数呈逐年波动上升趋势。（2）总体而言，保护区处于"安全"状态，仅个别年份受地质灾害影响，降至"临界安全"水平，安全等级演变历程为"安全-临界安全-安全-临界安全-安全"。（3）保护区生态安全的障碍主要来自于响应层，主要障碍指标为保护区居民数年增长率（C2）、地质灾害发生次数（C6）和法律完善程度（C22），障碍度分别为12.63%、10.53%和9.47%。（4）随着灾害防治措施和管理体制的不断优化完善，最大障碍因子经历了由法律完善程度（C22）、污水处理设施完善程度（C20）和地质灾害防控措施完善程度（C17）到地质灾害发生次数（C6）、保护区居民数年增长率（C2）的变化。未来需加大环境保护投入力度、提升灾害防治技术和保护管理应对措施，进一步优化社区共管体制，探索自然保护与社区居民和谐可持续发展的科学路径，稳步提升九寨沟保护区生态安全水平。;Ecological security is an important cornerstone of the national security system. Nature reserves are important safety barriers to maintain regional biodiversity, which play an important role in water conservation and ecological balance, and can effectively alleviate the damage of social development to the natural environment. Jiuzhaigou National Nature Reserve is located in a sensitive area, the ecological security status of the Jiuzhaigou Nature Reserve under the impact of natural disasters and human activities has attracted much attention. On the basis of comprehension and analysis of eco-security, 23 assessment indexes were selected by the Pressure-State-Response (PSR) model and obstacle factors analysis from the aspects of natural environment, human activities and social economy to evaluate the ecological security status of Jiuzhaigou National Nature Reserve and identify the main obstacle index of Jiuzhaigou from 2001 to 2019. The results show that (1) the level of ecological security in Jiuzhaigou National Nature Reserve has been gradually improved from 2001 to 2019, with the index increasing from 0.7933 to 0.8623. Among them, the pressure and state index indicated a downward trend of fluctuations, and the response index presented an upward trend. (2) In general, Jiuzhaigou National Nature Reserve was in a safety state, and only a few years were affected by geological disasters and fell to the critical safety level. The evolution of the safety level is in the order of safety, critically safety, safety, critically safety and safety. (3) In criteria layer, the main obstacle of the ecological security came from the pressure layer, and the main obstacle index were the annual growth rate of residents in nature reserve (C2), the frequency of geological disasters (C6) and the degree of legal revision (C22), with the degree of obstacles 12.63%, 10.53% and 9.47%, respectively. (4) With the improvement of disaster prevention and management system, the main obstacle factors changed from the degree of legal revision (C22), the degree of sewage treatment (C20) and the degree of geological disaster prevention (C17) to the frequency of geological disasters (C6) and the annual growth rate of residents in nature reserve (C2). To improve the ecological security, the environmental investment should be increased, environmental protection intensified, prevention of natural disasters improved. At the same time, measures should be taken to optimize the system of community co-management, explore the scientific path for harmonious and sustainable development of natural protection and community residents, and steadily improve the level of ecological safety of Jiuzhaigou National Nature Reserve.

Phytoplankton community structure and ecological evaluation in summer, Lake Changhai of Jiuzhaigou National Nature Reserve

高山湖泊对于全球气候变化及人类影响是一个极为敏感的参照系统.九寨沟国家级自然保护区长海作为一个独特的高山湖泊，研究其浮游植物群落结构及其与环境的关系，评估其水质现状及影响因素，有着重要的意义.本文于2014年7月对长海浮游植物群落结构进行了研究.全湖共布设12个采样点，并在中心采样点进行了垂直分层采样.本次调查共发现浮游植物6门38属63种，平均丰度为6.98×10⁵ cells/L，平均生物量为0.31 mg/L.浮游植物的水平分布差异不大；在垂直分布上，浮游植物的丰度从表层0.5 m至水下50 m呈现先增加后减少的趋势，在20 m水深处达到最大.长海浮游植物的优势种是长海小环藻（Cyclotella changhai）和飞燕角甲藻（Ceratium hirundinella），长海小环藻数量较多，飞燕角甲藻生物量较大.长海浮游植物多样性指数较低，综合各类水质评价方法，可以得出九寨沟长海处于贫-中营养状态.;Alpine lakes are sensitive reference systems of global climatic change and other human impacts. As a unique alpine lake, Lake Changhai of Jiuzhaigou National Nature Reserve has important significance in studying its phytoplankton community structure and it's relationship with the environment. It is also important to assess the status of water quality and its influencing factors. In order to understand the phytoplankton community structure, 12 sites were selected to collect phytoplankton samples in July 2014. Vertical stratified sampling was performed at the central sampling point. The 63 taxa of phytoplankton belonging to 38 genera in 6 phyla were identified, the average phytoplankton abundance was 6.98×10⁵ cells/L, the average phytoplankton biomass was 0.31 mg/L. There is no significant difference in the horizontal distribution of the phytoplankton. In the vertical distribution, the abundance of phytoplankton increased first and then decreased from 0.5 m to 50 m, and reached the maximum at the depth of 20 m. Cyclotella changhai and Ceratium hirundinella were the dominant species. Cyclotella changhai were higher amounts, Ceratium hirundinella were higher biomass. The phytoplankton diversity index was low. Synthesizing all kinds of methods to evaluate water quality, Lake Changhai was in a poor-medium pollution state.

Wet deposition of sulfur and nitrogen in Jiuzhaigou National Nature Reserve, Sichuan, China during 2015-2016: Possible effects from regional emission reduction and local tourist activities.

In order to understand the impacts of regional emission changes and local tourism on sulfur and nitrogen wet deposition in Jiuzhaigou National Nature Reserve of southwestern China, wet deposition was monitored at a background site (Rize) and a tourist-affected site (PE: park entrance) in the reserve during 2015-2016. The observation data were compared between Rize and PE and between 2010-2011 and 2015-2016 monitoring campaigns. Also, the observation data were used in the Positive Matrix Factorization (PMF) model to identify the major sources of sulfur and nitrogen wet deposition. The results show that although local tourism emissions had considerable contributions to NH4+, NO2-, NO3-, and SO42- concentrations in wet deposition (p<0.05), most of the annual Volume Weighted Mean (VWM) concentrations of these four ions were likely from emissions outside Jiuzhaigou. Annual wet deposition fluxes of the four ions were also affected more by precipitation and regional emissions than by local emissions. Although annual precipitation was higher at Rize (818mm) during 2015-2016 than at another background site near Long Lake (LL: 752mm) during 2010-2011, the annual concentrations and fluxes of SO42- and NO3- wet deposition decreased by 77% and 74% for SO42- and by 12% and 19% for NO3-, respectively, most likely due to regional emission reductions. Similar large reductions in SO42- and NO3- concentrations have been also found in some other sites in southwestern China. In contrast, the annual concentration and flux of NH4+ wet deposition at Rize during 2015-2016 were 1.4 and 1.2 times of that measured at LL during 2010-2011, respectively. The results of source apportionment analysis and tour bus emission estimates suggest that elevated NH4+ wet deposition was possibly related to NH3 emissions from local tour buses, but additional studies on NH3 emissions from tour buses in the reserve are needed to confirm this.

Factors Affecting Tufa Degradation in Jiuzhaigou National Nature Reserve, Sichuan, China

Water and tufa samples were collected from Arrow Bamboo Lake, the stream from Panda Lake to Five-Color Lake, Pearl Shoal and Shuzheng Lakes in Jiuzhaigou National Nature Reserve, China, between October 2013 and September 2014, to investigate tufa growth rate and water environment (water temperature, pH, electric conductivity, major ions and nutrients), and analyzed to explore the main causes of tufa degradation. The mean annual rate of tufa growth was low and varied within lakes, with the maximum deposit thickness of 332 μm/y. The calcite saturation index ranged from 0.65 to 0.83. Scanning electron microscope images showed that the tufa deposits had non-isopachous structures, and diatoms were the dominant microorganisms that participated in tufa deposition. Porous and crystalline structures of deposits were linked with a high tufa growth and small amounts of diatoms. Conversely, tufa deposits with amorphous and loose structures showed a low crystal growth rate and a high number of diatoms. A one-way analysis of variance and a least significant difference test were applied to identify site differences in water chemistry. Linear correlations indicated that nitrate, phosphate and sulfate inhibit tufa growth (p &lt; 0.05). Increased nitrogen and phosphorus concentrations that originate mainly from atmospheric pollution and tourist activities at scenic attractions could trigger excessive diatom growth, which inhibits tufa precipitation. A series of measures should be implemented (e.g., the visitor number and vehicles should be regulated and controlled) to minimize tufa degradation in the Jiuzhaigou National Nature Reserve.

Seasonal Pattern In the High-Elevation Fluvial Travertine From the Jiuzhaigou National Nature Reserve, Sichuan, Southwestern China

Abstract: The Jiuzhaigou National Nature Reserve on the Tibetan Plateau (Sichuan, southwestern China) is characterized by the deposition of fluvial travertine in a spectacular array of shoals, waterfalls, pool dams, and multicolored lakes. This is possibly the highest vegetated travertine setting of the world, from 2200 to 2900 m above sea level, an environment sensitive to minimal changes in temperature and precipitation regime. The evolution of the system is driven by two seasonal monsoon climate patterns with a wet spring–summer travertine deposition and then a dry fall–winter characterized by no precipitation or erosion. Spring and phreatic–vadose deposits transition from laminated columnar calcite to clotted micrite encrustation, possibly correlated with a mid-Holocene peak in precipitation and high lake levels in the northeastern Tibetan area connected to glacial advance. The most peculiar features are the fluvial shoals, a rather uncommon travertine surface consisting of two main superimposed facies of alternating weak- and strong-turbulence water flow. The low-turbulence facies consists of clotted micrite encrustation of mosses and cyanobacteria filaments, and platy calcite crystals covering algal filaments. The high-water-turbulence facies show seasonal alternation of diatom-rich bundles of Phormidium sp. (late spring) with algal Oocardium stratum levels (summer–fall). Upslope and downslope of the shoals, the precipitation of calcium carbonate results in the formation of prograding waterfalls and dam–pool systems that encrust macrophytes with microspar and clotted micrite. Encrusted chironomids larvae tubes are present in the waterfall walls up to an elevation of 2860 m, possibly the highest ever recorded. Early diagenetic processes such as dissolution of diatom frustules take place over the span of several years, a slower phenomenon compared to other travertine occurrences. In this high-elevation extreme setting, travertine sand and gravel bar deposits are produced by the exposure to severe weathering of a section of the valley that is bypassed through an underground karst system during the winter dry season. High-elevation travertine probably has a low preservation potential, but it appears to be more sensitive to climate changes than other depositional settings, especially in the Himalayan–Tibetan area, where the extent of the Quaternary glacial advances and retreats is still a matter of debate.

Unintended Side Effects of Conservation: A Case Study of Changing Land Use in Jiuzhaigou, Sichuan, China

Toward the goals of returning the landscape of Jiuzhaigou National Nature Reserve to a perceived “natural” state and protecting the environment, the Reserve in 1998–2002 implemented forest preservation policies that included restrictions on forestry, agriculture, and animal herding practiced by resident Tibetans. To document the effects of these land use changes on landscape diversity and on human vulnerability to natural hazards, we mapped and characterized topographic parameters of anthropogenic treeless areas from 1973, 2004, and 2013 satellite images. Results showed that, in addition to a previously documented overall loss of cleared land, the distribution of treeless area elevation, aspect, and slope has changed. In 1973, treeless areas were distributed approximately uniformly across all elevations and a wide range of slopes, but now they are concentrated on relatively flat slopes in the valley bottoms (∼2400 m) and high, subalpine elevations (∼3800 m). These changes are decreasing the topographic diversity of landscapes people use and likely also decreasing the biodiversity of the Reserve, where plant communities are highly stratified based on both elevation and aspect. In addition, many 1973 treeless areas were located on deep-seated landslides, while many 2004 and 2013 treeless areas were located on landslide deposits and alluvial fans, suggesting that relocation may not be reducing the risk of natural hazards for residents. These effects combine with the previously documented decline in overall area of montane meadows and associated losses to cultural heritage, ecosystem services, and biodiversity.

Are climate warming and enhanced atmospheric deposition of sulfur and nitrogen threatening tufa landscapes in Jiuzhaigou National Nature Reserve, Sichuan, China?

Massive deposition of calcium carbonate in ambient temperature waters (tufa) can form magnificent tufa landscapes, many of which are designated as protected areas. However, tufa landscapes in many areas are threatened by both local anthropogenic activities and climate change. This study, for the first time, posed the question whether the tufa landscape degradation (characterized by tufa degradation and increased biomass of green algae) in Jiuzhaigou National Nature Reserve of China is partially caused by regional air pollution and climate warming. The results indicate that wet deposition (including rain and snow) polluted by anthropogenic SO2, NOx, and NH3 emissions dissolves exposed tufa and may considerably reduce tufa deposition rate and even cause tufa dissolution within shallow waters. These effects of wet deposition on tufa enhanced as pH of wet deposition decreased from 8.01 to 5.06. Annual Volume Weighted Mean concentration of reactive nitrogen (including NH4+ and NO3−) in wet deposition (26.1μmolL−1) was 1.8 times of the corresponding value of runoff (14.8μmolL−1) and exceeded China's national standard of total nitrogen in runoff for nature reserves (14.3μmolL−1), indicating a direct nitrogen fertilization effect of wet deposition on green algae. As water temperature is the major limiting factor of algal growth in Jiuzhaigou and temperature in the top layer (0–5cm) of runoff (depth<1m, no canopy coverage of trees and shrubs) was significantly higher at the sites with increased biomass of green algae (p<0.05), climate warming in this region would favor algal growth. In sum, this study suggests that climate warming and enhanced sulfur and nitrogen deposition have contributed to the current degradation of tufa landscape in Jiuzhaigou, but in order to quantify the contributions, further studies are needed, as many other anthropogenic and natural processes also influence tufa landscape evolution.

九寨沟自然保护区川金丝猴的分布及种群数量

PDF HTML阅读 XML下载 导出引用 引用提醒 九寨沟自然保护区川金丝猴的分布及种群数量 DOI: 10.5846/stxb201410031948 作者: 作者单位: 陕西省动物研究所,西华师范大学生命科学学院,陕西省动物研究所,陕西省动物研究所,四川省自然资源科学研究院野生动植物种质资源保护与可持续利用四川省重点实验室,四川省自然资源科学研究院野生动植物种质资源保护与可持续利用四川省重点实验室,九寨沟自然保护区管理局,陕西省动物研究所、西北大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学重点基金资助项目(31130061); 国家自然科学基金资助项目(31470214, 30900168); 陕西省科学院基金资助项目(2014K-12, 2013K-34, 2013K-35, 2012K-01); 西部之光人才培养计划资助项目(2011DF05); 日本Cosmo石油环保卡基金资助项目(2005-2015); 四川省科技计划项目(2014SZ0147) Distribution and population of Rhinopithecus roxellana in Jiuzhaigou National Nature Reserve, Sichuan Province, China Author: Affiliation: Institute of Zoology,Shaanxi Academy of Sciences,Xi’an,College of Life Sciences, China West Normal University, Nanchong,Institute of Zoology,Shaanxi Academy of Sciences,Xi’an,Institute of Zoology,Shaanxi Academy of Sciences,Xi’an,Sichuan Province Natural Resources Science Academy Wildlife Germplasm Resources Conservation and Sustainable Utilization Key Laboratory, Chengdu,Sichuan Province Natural Resources Science Academy Wildlife Germplasm Resources Conservation and Sustainable Utilization Key Laboratory, Chengdu,Jiuzhaigou National Nature Reserve Management, Abazhou,Institute of Zoology,Shaanxi Academy of Sciences,Xi’an;Northwest University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:2014年2月至5月,对四川省九寨沟自然保护区野生川金丝猴的种群分布、数量及其社会结构进行调查,初步探讨该种群与其他种群在外部形态和社会结构方面的差异性。采用"V"型路线法调查,发现九寨沟保护区共有川金丝猴4群。然后结合长时间的持续跟踪观察,证实家庭单元19个,全雄群3个,能区分不同个体296只。OMU大小平均为12.7只,其中OMU内的成年个体占38%,青少年个体占53%,幼仔占9%。成年与青少年比例为1:1.39,成年雌雄的比例为3.84:1。与秦岭种群的外部形态相比,该种群的成年雄性更为壮大,毛发弯曲程度明显;成年雌性毛发略显灰黑色,金黄色暗淡,大部分个体嘴角长有很小的肉瘤;青少年个体毛色泛白。亦发现九寨沟种群倾向于选择海拔偏高(2400-3550 m)的针叶林带活动。 Abstract:The Sichuan snub-nosed monkey (Rhinopithecus roxellana), a rare primate in China, has suffered rapid population decline over recent decades. This primate inhabits the temperate forests in the mountainous highlands of Sichuan, Shaanxi, Gansu, and Hubei Provinces in China, at 1500 m to 3400 m above sea level. Most of the previous studies on Rhinopithecus roxellana have been carried out in Shaanxi Province, and there have been fewer studies in Sichuan Province. A population survey conducted in Sichuan Province in 1994 showed that the species is widely distributed in the forests along the mountainsides of Minshan, Qionglai, and Liangshan, with the majority residing in the Minshan Mountain forests. Jiuzhaigou National Nature Reserve is located on the southern slope of the Minshan Mountains in northwest Sichuan Province. R. roxellana is a multi-level social primate with groups consisting of several units, each comprising a breeding male, several adult females, and their offspring. We sought the help of the local villagers to obtain information on the approximate distribution of the monkey population in the nature reserve. We used this information to select the study regions where the distribution, social structure, and population of R. roxellana were measured in an attempt to analyze their adaptability in the Jiuzhaigou National Nature Reserve, Sichuan Province. The data were collected from February to May 2014, and during the last 75 days of this period, we used a V-shaped transect for the survey. When a group was observed, we recorded the height at which the group members were observed, the location and time of encounter, direction of the group's movement, sex and age of all individuals, habitat structure at that location, and the plants species on which the group was feeding. Our survey results confirmed that 4 groups, 19 One Male Units (OMUs) and 3 All Male Units (AMUs), resided within the reserve. One of the 4 groups that we followed for 8 days ranged across areas from Jiuzhaigou to Baihe. We confirmed 296 individuals in the 4 groups, with the OMUs having an average of 12.7 members, of which 38% were adults, 53% were juveniles, and the remaining 9% were infants. The average ratio of adults to juveniles was 1:1.39, while the ratio of females to males was 3.84:1. The primary distribution of the social groups was in Zarugou in Jiuzhaigou Nature Reserve, an area on the southern face of the mountain that receives adequate sunlight and is near the Baihe Nature Reserve. The groups were observed to be the most active in coniferous forest, at heights between 2400 m and 3550 m. When compared to the Qinling golden monkeys, Jiuzhaigou monkeys showed the following differences in body size and color of the hair on their backs:adult Jiuzhaigou males seemed stronger than the Qinling monkeys and had longer hair; the hair on the backs of adult Jiuzhaigou females was less golden and more black, and most of them had caruncles at the corners of their mouths; and the hair of juvenile Jiuzhaigou monkeys was whiter than that of Qinling monkeys. Thus, these two groups may be different subspecies, based on their morphological differences. 参考文献 相似文献 引证文献

Leaf decomposition and nutrient release of dominant species in the forest and lake in the Jiuzhaigou National Nature Reserve, China

Leaf decomposition and nutrient release of dominant species in the forest and lake in the Jiuzhaigou National Nature Reserve, China