Zhalong National Nature Reserve Research Articles

Comparison of the Intestinal Bacterial Communities between Captive and Semi-Free-Range Red-Crowned Cranes (Grus japonensis) before Reintroduction in Zhalong National Nature Reserve, China.

The wild populations of red-crowned cranes (Grus japonensis) in west China are gradually decreasing, necessitating the optimization of reintroduction measures. This study used 16S rRNA high-throughput sequencing technology to compare the gut microbiota communities of cranes living in two modes (captive and semi-free-range) before their reintroduction in Zhalong National Nature Reserve, Heilongjiang Province, China. The results showed that Proteobacteria (74.39%) and Firmicutes (25.29%) were the dominant gut bacterial phyla inhabiting these cranes. Significant differences were found in the gut microbiota community composition between semi-free-range and captive cranes (p < 0.01). Psychrobacter, Sporosarcina, and Lactococcus were significantly enriched in captive cranes (p < 0.05), while Pseudomonadaceae_Pseudomonas, Pantoea, Lysobacter, and Enterobacteriaceae_Pseudomonas were more abundant in semi-free-range cranes (p < 0.05). The functions and community structure of gut microbiota were affected by feeding patterns (p < 0.05). The metabolic pathways of ethylbenzene degradation, PPAR signaling pathway, betalain biosynthesis, systemic lupus erythematosus, and shigellosis were up-regulated in semi-free-range cranes (p < 0.05).

Multi-Factor Collaborative Analysis of Conservation Effectiveness of Nature Reserves Based on Remote Sensing Data and Google Earth Engine

Protected areas (PAs) play a crucial role in safeguarding biological resources and preserving ecosystems. However, the lack of standardized and highly operational criteria for evaluating their conservation effectiveness, particularly across different ecological types, remains a significant gap in the literature. This study aims to address this gap by constructing a conservation effectiveness evaluation model for two distinct types of PAs in Heilongjiang Province, China: the Zhalong National Nature Reserve (ZlNNR), a wetland ecological reserve; and the Mudanfeng National Nature Reserve (MdfNNR), a forest ecological reserve. We employed various methods, including land use dynamic index, visual analysis of landscape patterns, remote sensing inversion, and a multi-factor comprehensive assessment model, to assess changes in conservation effectiveness from 2000 to 2020. Our findings reveal a contrast between the two PAs. In the ZlNNR, croplands and water bodies increased significantly by 4069.4 ha (K = 1.5820%) and 2541.58 ha (K = 3.2692%). In the MdfNNR, impervious lands increased greatly by 65.35 ha (K = 7.4021%), whereas forest lands decreased by 125 ha (K = −0.067%). The core area of the two PAs displayed increased landscape regularity, whereas the experimental area showed heightened landscape diversity. In ZlNNR, the MPSL value increased by 134.91%, whereas the PDL value decreased by 57.43%, indicating a more regular landscape pattern. In MdfNNR, the SHDIL value decreased by 110.7%, whereas the PDL value increased by 52.55%, indicating a more fragmented landscape pattern. The area with improved vegetation trends in ZlNNR was 8.59% larger than in MdfNNR, whereas the area with degraded vegetation trends was 4.86% smaller than in MdfNNR. In all years, the high effectiveness area was larger in ZlNNR than in MdfNNR, whereas the medium and low effectiveness areas were smaller in ZlNNR compared to MdfNNR. This study provides a scientifically rigorous assessment method for evaluating the conservation effectiveness of different types of PAs, laying a solid theoretical foundation and practical guidance for future conservation strategies.

Modeling Hydrological Regimes of Floodplain Wetlands Using Remote Sensing and Field Survey Data

Understanding the variations in the water regimes of wetland ecosystems is crucial to analyzing the dynamics of wetland habitats under different water management policies and recharge conditions. A MIKE21 hydrodynamic model was constructed to simulate changes in the water level and flood extent from 1 May 2014 to 9 October 2014 in the Zhalong National Nature Reserve using field measurements, a digital elevation model (DEM), radar images, and climatic, meteorological, and land-use/land-cover data. The hydrodynamic model was calibrated and validated by water levels derived from hydrological gauge stations and water level loggers and the flooding extent was derived from multi-temporal synthetic aperture radar (SAR) images in different periods to evaluate the suitability of the hydrodynamic model for simulating wetland hydrological processes. The results demonstrated that the hydrodynamic model could simulate changes in the water level and flooding of the wetlands in the entire hydrological year. Accurate simulations were obtained for both calibration and evaluation with high correlations between the simulated and observed water levels. The simulated fine-scale hydrological regimes of semi-enclosed floodplain wetlands could be used to understand the ecohydrological processes affected by different water resource allocation schemes.

Wetland mapping based on feature optimization and Google Earth Engine in Zhalong Nature Reserve

Wetlands have very important and irreplaceable ecological service functions in protecting biodiversity and maintaining ecological balance. Due to the unique hydrological characteristics of wetlands, large-scale wetland mapping methods are usually time-consuming, labor intensive, and expensive. With the rise of big data and cloud computing platforms, there are opportunities for long time series and large-scale spatial data processing that improve large-scale wetland mapping. In this study, the Sentinel-1, Sentinel-2, and digital elevation model derived from the Google Earth Engine were used to extract the wetland extent in the Zhalong Nature Reserve based on the Jeffries–Matusita (JM) distance for feature optimization and random forest. Research shows the following: (1) The JM distance for each feature showed that the optical features had the highest separation in all five features and (2) the classification after feature optimization performed best. User accuracy (UA) and producer accuracy (PA) for wetland reached 89.64% and 83.00%, respectively, and overall accuracy reached 90.76%. After feature optimization, PA and UA of wetland were each increased 4.26% and 1.07%, respectively, and the number of features was reduced from 46 to 28. The method used in this study is highly accurate in wetland mapping and can effectively avoid the problem of data redundancy.

Does Ecological Water Replenishment Help Prevent a Large Wetland from Further Deterioration? Results from the Zhalong Nature Reserve, China

Ecological water replenishment (EWR) has been increasingly applied to the restoration and maintenance of wetland hydrological conditions across China since the beginning of the 21st century. However, little is known about whether EWR projects help protect and/or restore wetland ecohydrology. As one of the earliest and longest-running EWR projects in China, water has been released from the Nenjiang River into the Zhalong wetland since 2001. It is important to examine the ecohydrological effects of this EWR project. In this study, long time series remote sensing data were used to extract the water area, inundation frequency, and normalized difference vegetation index (NDVI) to explore how eco-hydrological conditions changed during the pre- (1984–2000) and post-EWR (2001–2018) periods in the Zhalong wetland. Results show that the inundation area decreased due to the reduced surface water inflow during the pre-EWR period. Similarly, monthly vegetation NDVI in the growing season generally exhibited a decreasing and an increasing trend during the pre- and post-EWR periods, respectively. In the post-EWR period, NDVI increased by 19%, 73%, 45%, 28%, 13% for the months of May through September, respectively. Due to EWR, vegetation growth in areas with low inundation frequency was better than in areas with high inundation frequency. We found that the EWR project, runoff, and precipitation contributed 25%, 11%, and 64% to changes in the NDVI, respectively, and 46%, 37%, and 17% to changes in inundation area, respectively. These results indicate that the EWR project has improved hydrological conditions in the Zhalong wetland. For further maximum benefits of EWR in the Zhalong wetlands, we suggest that implementing similar eco-hydrological projects in the future should focus on flood pulse management to increase the inundation area, improve hydrological connectivity, and create new habitats.

Which is more Important, Ecological Conservation or Recreational Service? Evidence from a Choice Experiment in Wetland Nature Reserve Management

To achieve the common goal of sustainable development of wetland ecotourism, the nature reserve managers face the challenge of balancing ecological protection and tourism demand. To make appropriate management strategies, more information is needed to understand how visitors evaluate the ecological and recreational attributes, as well as the willingness to pay and preferences. Choice experiment (CE) was employed to explore the trade-offs of visitors between ecological conservation and recreational services in Zhalong National Nature Reserve (ZNNR) in Northeast China, and the analysis of socioeconomic and attitudinal factors was added to reveal the preference heterogeneity. The results showed that biodiversity was the most highly valued attribute and increasing biodiversity or/and environmental education facilities were both valuable scenarios for wetland development. The differentiation of preferences is influenced by both socioeconomic and attitudinal factors including gender, income, age, work situation and environmentally responsible behavior. Two classes of visitors were divided through preference heterogeneity for each attribute, i.e. eco-friendly and price sensitive. These results could help to formulate reasonable policy implications and management strategies for wetland ecotourism. The proposed research framework clarifies the procedure and application of CE and provides a new perspective for trade-off problem in wetland nature reserve management.

Listen to the Voices from Tourists: Evaluation of Wetland Ecotourism Satisfaction Using an Online Reviews Mining Approach

Scientific evaluation of tourist satisfaction could contribute to the sustainable development of wetland ecotourism. With the development of Web 2.0, online travel reviews increase significantly which provide valuable information for evaluating tourist satisfaction. Hence, this study aims to evaluate the tourist satisfaction of wetland ecotourism in Zhalong National Nature Reserve (ZNNR) based on online travel reviews. Tourist satisfaction evaluation model and sentiment analysis were applied to calculate satisfactions of evaluation factors that were uncovered based on latent dirichlet allocation model. The results suggest that total satisfaction was 0.614, at the fundamentally satisfied level. Moreover, we identified 11 controllable evaluation factors that were key for ZNNR to manage interaction with tourists, and further aggregated these factors into three categories: ecotourism experience, natural resource and cultural resource. Especially, importance-performance analysis further identified the most important evaluation factors according to four-quadrant weight-satisfaction matrix. The proposed analytical framework expands the understanding of the methodological challenges and offers novel perspectives for evaluating the tourist satisfaction. These findings could provide useful insights for the sustainable development of ecotourism and effective management of wetlands.

Using MaxEnt Model to Guide Marsh Conservation in the Nenjiang River Basin, Northeast China

Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas (PAs) and improve the efficiency of conservation. But how to select patches of land for conservation is still a troublesome issue. In this study, the MaxEnt model and irreplaceability index were applied to guide marsh conservation in the Nenjiang River Basin, Northeast China. According to the high accuracy of the MaxEnt model predictions (i.e., the average AUC value = 0.933), the Wuyuer River and Zhalong marshes in the downstream reaches of Wuyuer River are the optimal habitat for the Red-crowned crane and migratory waterfowls. There are 22 marsh patches selected by the patch irreplaceability index for conservation, of which 12 patches had been included in the current network of protected areas. The other 10 patches of marsh (amounting to 1096 km2) far from human disturbances with high NDVI (up to 0.8) and close distance to water (less than 100 m), which are excluded from the existing network of PAs, should be implemented conservation easement programs to improve the protection efficiency of conservation. Specifically, the marshes at Taha, Tangchi, and Lamadian should be given priority for conservation and restoration to reintroduce migratory waterfowls, as this would lessen the current isolation state of the Zhalong National Nature Reserve.

Assessment of land ecosystem health with Monte Carlo simulation: A case study in Qiqihaer, China

A better understanding of the level of land ecosystem health in a region is helpful for policymakers in developing measures for eco-space management. During the evaluation process, uncertainty is inevitable because of different methods of determining the related weights. In this study, a Monte Carlo simulation was used to construct a sample of the indicator weights to quantify the uncertainty in the process of land ecosystem health assessment to improve the accuracy of the assessment result. This study used a new evaluation framework of pressure, state (vigor-organization -resilience-function) and response to assess the level of land ecosystem health in Qiqihaer City from 2000 to 2015. Then, the spatial heterogeneity among the levels of land ecosystem health was examined using hotspot spatial analyses. Our results showed the following: (1) the overall level of land ecosystem health in Qiqihaer city was ordinary (Ⅲ), and the average values of the related indices were 0.554 (2000) and 0.563 (2015). Hotspots and coldspots identified by the land ecosystem health index had obvious overlapping areas from 2000 to 2015, among them, approximately 30.6% of the hotspot area (high-value area) was located in the Zhalong Nature Reserve, and approximately 15.6% of the coldspot area (low-value area) was located in city centres and the boundary of the study area. (2) The average values of the land ecosystem health pressure and response indexes were low, while the average values of the land ecosystem health states index changed greatly. However, in terms of spatial heterogeneity, the spatial differences were small for the pressure index and the states index, and the spatial difference in the response index was large. The assessment results objectively reflect the health status of the regional land ecosystem and have very important theoretical and practical significance for safeguarding similar regional ecological security and promoting social and economic sustainable development.

A new species of &lt;i&gt;Pleurotaenium&lt;/i&gt; N&amp;#228;geli (Desmidiales) in Zhalong National Nature Re-serve,NE China

2011-2012年间对扎龙国家级自然保护区的藻类标本进行采集及观察鉴定.研究发现，该区域鼓藻类植物生物多样性较高，共观察到90个分类单位.研究过程中发现宽带鼓藻属的一个新种——Pleurotaenium parvulum Li，Fan&Wei.该物种特征为植物体单细胞，细胞小型，长圆柱形；半细胞顶端平截，其缘边横断面可见5个小结节；细胞壁平滑或具点纹；半细胞具两个轴生星状的色素体，每个色素体具1个蛋白核.本文比较了该物种与其相近种类之间的差异.;A very abundant desmids biota was found in Zhalong National Nature Reserve in 2011-2012,including 90 taxa in total.Among them,a Pleurotaenium species is proposed as new to science,Pleurotaenium parvulum Li,Fan&Wei.The new species is characterized of small cells and a long cylinder without processes,a truncated apex,five small nodules on cross section,cell wall smooth or with puncta,semicells with two axial longitudinal ridge-shaped chromatoplasts,and each with two pyrenoids.Differences between the species and allied taxa are discussed.

扎龙保护区春季丹顶鹤觅食的农田生境利用分析

扎龙保护区春季丹顶鹤觅食的农田生境利用分析

A novel unsupervised bee colony optimization (UBCO) method for remote-sensing image classification: a case study in a heterogeneous marsh area

ABSTRACTUnsupervised image classification is an important means to obtain land-use/cover information in the field of remote sensing, since it does not require initial knowledge (training samples) for classification. Traditional methods such as k-means and Iterative self-organizing data analysis technique (ISODATA) have limitations in solving this NP-hard unsupervised classification problem, mainly due to their strict assumptions about the data distribution. The bee colony optimization (BCO) is a new type of swarm intelligence, based upon which a simple and novel unsupervised bee colony optimization (UBCO) method is proposed for remote-sensing image classification. UBCO possesses powerful exploitation and exploration capacities that are carried out by employed bees, onlookers, and scouts. This allows the promising regions to be globally searched quickly and thoroughly, without becoming trapped on local optima. In addition, it has no restrictions on data distribution, and thus is especially suitable for handling complex remote-sensing data. We tested the method on the Zhalong National Nature Reserve (ZNNR) – a typical inland wetland ecosystem in China, whose landscape is heterogeneous. The preliminary results showed that UBCO (overall accuracy = 80.81%) achieved statistically significant better classification result (McNemar test) in comparison with traditional k-means (63.11%) and other intelligent clustering methods built on genetic algorithm (unsupervised genetic algorithm (UGA), 71.49%), differential evolution (unsupervised differential evolution (UDE), 77.57%), and particle swarm optimization (unsupervised particle swarm optimization (UPSO), 69.86%). The robustness and superiority of UBCO were also demonstrated from the two other study sites next to the ZNNR with distinct landscapes (urban and natural landscapes). Enabling one to consistently find the optimal or nearly optimal global solution in image clustering, the UBCO is thus suggested as a robust method for unsupervised remote-sensing image classification, especially in the case of heterogeneous areas.

基于MAXENT模型的丹顶鹤营巢生境适宜性分析——以扎龙保护区为例

基于MAXENT模型的丹顶鹤营巢生境适宜性分析——以扎龙保护区为例

Assessing Breeding Habitat Suitability for the Endangered red-Crowned Crane (Grus japonensis) Based on Multi-Source Remote Sensing Data

Identifying the breeding habitat of red-crowned crane (Grus japonensis) is essential for the management and conservation of this rare species. In the current study, we built a habitat suitability index (HSI) model for the breeding red-crowned crane in wetlands of the Zhalong National Nature Reserve of the Songnen Plain, China. The assessing factors to construct the HSI model were selected according to the habitat requirements of red-crowned crane in the breeding period, including the potential nest site (emergent marsh), habitat composition (the area percentage of emergent marsh in species home range), water depth, vegetation cover, and distance to human disturbance. Efficient techniques have been used to quantify predictor variables using multi-source data (i.e. optical imagery, radar imagery and ancillary topographic data). In addition, we illustrated the extraction method of habitat factors in detail and the significances of these factors in evaluating the breeding habitat suitability for the red-crowned crane. Analysis results indicated that the GIS-based HSI model successfully identified potentially suitable red-crowned cranes nesting sites. This analysis not only enables wildlife managers to identify priority locations and conservation status for red-crowned crane, but also provides an effective and prompt method that can be used to infer other waterfowl species nest sites.

Nest site characteristics and nest loss of Marsh Grassbird at Zhalong National Nature Reserve, China

The Marsh Grassbird Locustella pryeri is an uncommon songbird endemic to East Asia. Suitable nest- site selection can minimize nest loss, especially for open- cup and ground nesting passerines. We located and mon- itored 66 Marsh Grassbird nests during 2004-2006 in Zhalong National Nature Reserve, northeast China, to identify characteristics of preferred nest sites. Marsh Grassbird nested mainly at sites with dense vegetation cover, high undergrowth and dry standing reed stalks, as well as small shallow ponds or rivers. Nests were more successful when they were placed higher above ground in patches with greater litter thickness. Predation and flooding were the leading causes of nest failure, accounting for at least 33 and 25 % of 24 nests lost, respectively. We ad- vocate retention of some unharvested reed patches and implementation of irrigation strategies that avoid increas- ing water levels during the breeding period (May-July) of Marsh Grassbirds.

食物可获得性对冬季丹顶鹤能量收支的影响——以扎龙自然保护区人工辅助繁育丹顶鹤为例

PDF HTML阅读 XML下载 导出引用 引用提醒 食物可获得性对冬季丹顶鹤能量收支的影响——以扎龙自然保护区人工辅助繁育丹顶鹤为例 DOI: 10.5846/stxb201406161246 作者: 作者单位: 东北林业大学野生动物资源学院;齐齐哈尔大学生命科学与农林学院,东北林业大学野生动物资源学院,黑龙江扎龙国家级自然保护区,黑龙江扎龙国家级自然保护区,黑龙江扎龙国家级自然保护区 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(31470016) The influence of the different food availability in winter on energy budget of Red-crowned crane (Grus japonensis) in Zhalong Nature Reserve Author: Affiliation: College of Wildlife Resources,Northeast Forestry University;College of Life Science,Agriculture and Forestry,Qiqihaer University,College of Wildlife Resources,Northeast Forestry University,Zhalong Nature Reserve,Zhalong Nature Reserve,Zhalong Nature Reserve 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:动物主要通过摄入食物和获得食物中的能量来维持其正常的生命活动。为论证食物获得性对冬季丹顶鹤能量收支的影响及为其越冬保护提供科学依据,以扎龙自然保护区人工辅助繁育丹顶鹤为研究对象,对分别供给鲫鱼、玉米和混合(鲫鱼+玉米)饲喂3组丹顶鹤的能量收支、体重及其行为变化进行比较。结果发现,丹顶鹤的能量收支受食物可获得性差异影响,鲫鱼、混合饲喂和玉米3组丹顶鹤的能量收支及排泄次数依次降低,玉米组丹顶鹤的体重降低显著(P < 0.01)及其行为谱中的静息时间分配明显增加。食物的可选择性、环境低温和短光照的交互作用使丹顶鹤的可摄食时间受限,丹顶鹤的能量收支随之发生变化。分析结果表明扎龙保护区冬季每日定时、定量供给鲫鱼和足量供给玉米的饲喂丹顶鹤的方法较为合理。 Abstract:For most animals, adequate food and energy intake is essential for the maintenance of normal life activities. Food intake-which depends on the availability of different foods, feeding time and palatability-is closely related to environmental factors, and is a critical factor affecting energy balance in some birds. The present study was designed to examine the impacts of differing food intake on energy budget and behavior in winter Red-crowned cranes (Grus japonensis), and to check the feasibility of the feeding method in Qiqihar, Heilongjiang Province, China. Red-crowned cranes were housed individually in cages (6m×4m×4m) in their natural habitat in Zhalong Nature Reserve (46°52'-47°32'N, 123°47'-123°37'E) during December 2013. Twenty-three adults older than 5 years of age were divided into three groups and fed a diet of crucian carp (4♀, 4♂), corn (4♀, 4♂), or a combination of both (4♀, 3♂), respectively. During the feeding experiment, they were maintained in natural conditions, with a short photoperiod of near 8L:16D and an average temperature of -12.8℃. After a week, we compared changes in behavior, body mass, energy budget and fecal discharge frequency among different diet treatments in the winter birds. The birds were weighed (to 0.01kg) by the breeder (Method: (A+B)-A, where A is the breeder's weight) at the start of the experiment, and then at weekly intervals over the period of food availability acclimation. At the same time every day during the experiment period, we chose two birds from each group and recorded the total distribution time of the different behaviors. Energy and water intake was measured for every bird. The amount of supplied and residual food was weighed every day of the experiment, and the caloric content of food intake was determined using an oxygen bomb calorimeter. The fecal discharge frequency was calculated by counting fecal deposits five times every day; after which the deposit was removed to ensure accurate measurement. After acclimatization, we found that the body mass and behavior of G. japonensis changed significantly with different diets. The body mass of birds feeding on corn was significantly lower than others after the effects of initial body mass were eliminated (P < 0.05), while the duration of resting behavior increased significantly (P < 0.001). Energy budgets were also significantly different between the three experimental groups after the effects of initial body mass were eliminated, including significant differences in the intake of food, water and energy, the cooling energy of water discharged, and the fecal discharge frequency (P < 0.05). Further, the food intake, energy intake and cooling energy of water discharged by birds feeding on corn were significantly lower than that of birds in the other two treatments. Indeed, many aspects could have influenced the observed differences among treatments in the energy budget and behavior of winter G. japonensis. For example, perhaps the feeding time for crucian carp was limited by the low temperature and short light cycle of experimental conditions. Poor palatability of corn kernels could have led to a decrease in food demand and hence energy intake. Finally, birds feeding on a combination of fish and corn could have received more abundant nutrition from the hybrid diet. To summarize, to maximize energy intake and nutrition in the species, it is necessary to consider the daily light cycle and temperature of the environment. Further, the method of mixed feeding at Zhalong Nature Reserve provides a more balanced diet to Red-crowned Cranes over winter. 参考文献 相似文献 引证文献

Diatom composition and its application in water quality assessment in the Zhalong National Nature Reserve, China

Diatom composition and its application in water quality assessment in the Zhalong National Nature Reserve, China

Nest site selection of white-naped crane (Grus vipio) at Zhalong National Nature Reserve, Heilongjiang, China

White-naped crane (Grus vipio) is a globally threatened species. It is very important to analyze its nest site selection in circumstances where there are multiple disturbances, and also helpful to accumulate valuable information about this threatened species and supply scientific suggestions for conservation and management. We studied nest site selection and the effects of environmental variables on nesting habits of white-naped crane at Zhalong National Nature Reserve, Qiqihar City, Heilongjiang, China, during March-May of 2002–2008. White-naped crane responded and adapted to changes in the quality of the spatial environments of landscape and microhabitat under multiple environmental disturbances. Nest site selection included two scales and two choices, namely the choice of nest site habitat type within the macro-habitat scale and nest site micro-habitat selection within the micro-habitat scale. Nest sites were recorded only in reed marshes. The choice of nest site micro-habitat included three basic elements and six factors, namely incubation element (nest parameters factor, incubation temperature factor and incubation humidity factor), safety element (protection factor and concealment factor), and food element (water factor). Water, remnant reed clusters, and fire were major resource management challenges during the breeding period for the white-naped crane in this Reserve.

Seasonal plasticity of duodenal morphology and histology in Passer montanus

When facing seasonal environmental changes, flying birds and small mammals may develop adaptive gastrointestinal changes to optimize their digestive and absorptive strategies to meet the changing of physiologic needs. As a main component of gastrointestinal tract, small intestine is extraordinarily sensitive to food abundance, food quality, and other environmental factors. However, the detailed morphological adaptations of the small intestine during seasonal changes are largely unknown. Here, we studied the morphological and histological dynamics of duodenum from Passer montanus in Zhalong Nature Reserve in China during seasonal changes. The luminal and wall cross-section area were greater in spring and autumn than that in summer. Villus height and width went up to peak values in winter and showed similar seasonal dynamic changes with that of mucosal thickness, while villus atrophy accompanied by the deepest crypt depth was easily detected in summer. Epithelium thickness was coincident with villus atrophy except a sharp increase in summer. Submucosal thickness was negatively correlated with that of mucosa, while the size, but not total number, of duodenal glands was altered to reflect to seasonal changes. Neither the inner circular nor the outer longitudinal muscle showed seasonal morphological changes, indicating the relatively stable plasticity of intestine muscle structures. Taken together, we propose that phenotypic flexibility in digestive morphology and histology enables small birds to cope with remarkable seasonal changes.

Correlation between the Avian Community and Habitat Type during the Wintering Period in Zhalong National Nature Reserve, China

Zhalong National Nature Reserve (Zhalong) is an important habitat of avian, especial for cranes and waterfowls. For grasping the relation between avian ecological group and habitat types and scientific management for resource, we used line transects to survey bird population and distribution during November-December from 2005-2009 at Zhalong, and used cluster analysis and Chi-Square tests to analyze data. We recorded 23 bird species of 15 families and 7 orders during the wintering period, including Anseriformes, Columbiformes, Falconiformes, Galliformes, Gruiformes, Passeriformes, Strigiformes. Geographic region and dominant vegetation were the main influence factors of wintering avian distribution at Zhalong. Different ecological groups preferred different habitat types (p&lt;0.01). Reed marsh were strong preferred, next were farmland and open forest. Passeres preferred reed marsh, open forest and farmland; Raptatores preferred open forest and reed marsh; Terrestores and Grallatores all preferred reed marsh and farmland. Different avian ecological groups occupied specific habitats types and we recorded some overlaps in bird distribution.