Humid Mountainous Areas Research Articles

The nonlinear rainfall–quick flow relationships in a humid mountainous area: Roles of soil thickness and forest type

The nonlinear behavior of hillslope quick flow (QF) in response to variations in soil thickness and forest types remains unclear due to uncertainties or unknown features in field studies, hindering accurate interpretation of their impact on QF. To this end, three artificial physical models with different mineral soil thickness (0 cm, shallow 50 cm, and thick 150 cm) beneath a 50 cm root zone for each forest (i.e., the broadleaf and coniferous forests) were constructed and intensively monitored. Results showed that the threshold-based QF was a function of the sum of rainfall amount and antecedent soil wetness, which was isolated by two breakpoints—the generation and rising thresholds—across all artificial physical models. These breakpoints indicated the storage thresholds for QF generation and the transition from slow to fast QF in humid forests. The broadleaf forest required more rainfall to reach the generation threshold due to higher litter interception capacity and soil water deficit by plant water uptake compared to the coniferous forest. Above the rising threshold phase, QF increased rapidly and linearly due to the establishment of flow path connectivity driven by soil water content, with the broadleaf forest showing a faster increase in QF than the coniferous forest. The dominant preferential/unsaturated flow in humid mountainous areas was also confirmed. Preferential flow paths were well-connected in the root zone and extended to the shallow mineral soil, resulting in an insignificant difference in mean QF between forest types. The thick mineral soil disrupted preferential flow path connectivity, leading to a greater amount of water being laterally diverted and retained within the soil. Consequently, a sharp decrease in QF was observed in hillslope with the root zone capping thick mineral soil for both forests. Our results highlighted the application of threshold-based theory and controlled experiments in enhancing the comprehension of the fundamental physical mechanism governing runoff processes in humid forests.

Effects of dry spells on soil moisture and yield anomalies at a montane managed grassland site: A lysimeter climate experiment

AbstractThe frequency and severity of droughts in the Alps are expected to increase due to rising air temperatures and changes in precipitation regimes. Although biomass production in humid mountain areas tends to be energy limited rather than water limited, an increase in droughts may have negative impacts on the water availability and thus agricultural yields. This study aimed to analyse the impacts of dry spells on soil moisture and yield anomalies at a montane permanent grassland site in Austria. Dry spells in the time period from 2018 to 2020 were identified using the Standardized Precipitation Index, Palmer Drought Severity Index and the Soil Moisture Anomaly Index. Data from a lysimeter climate experiment were used to evaluate drought impacts on soil water storage and grassland yield under ambient and manipulated conditions. The results indicated the occurrence of three extreme droughts between 2018 and 2020. Although the studied grassland is generally considered a nonwater‐limited ecosystem, the most extreme drought in summer 2019 caused severe and extreme yield anomalies under ambient and heated conditions. Only mild yield anomalies were observed on plots with elevated atmospheric carbon dioxide concentration. This drought‐mitigating effect was attributed to the water savings enabled by partial stomatal closure under elevated CO2. The shorter dry spells in spring and late summer 2018 led to more diverse effects; mildly to moderately negative yield anomalies were found on the heated plots, whereas the anomalies tended to be less negative or even positive on plots under ambient temperature. In contrast, some time periods without water stress showed positive effects of heating on yield. These findings suggest that drought impacts on a humid montane grassland depend on both water availability and air temperature. Higher air temperature can have positive effects on yield if the ecosystem is energy limited. However, global warming suggests a tendency from energy to water limitation, in which the increased evaporative demand of the atmosphere aggravates soil moisture droughts and thus has potentially negative effects on yield.

Spatial Distribution Characteristics and Influencing Factors of Pro-Poor Tourism Villages in China

This paper aims to contribute to the effectiveness of pro-poor tourism in rural areas. We use 5770 pro-poor tourism villages in China as the research objects; the spatial distribution characteristics of pro-poor tourism villages in China are analyzed using a combination of disequilibrium index, kernel density analysis, and spatial autocorrelation; their influencing factors are detected using a geographical detector and overlay analysis. The study results show the following: (1) The distribution of pro-poor tourism villages is exceptionally uneven in three zones, eight regions, and inter-provincial levels, forming a high-density cluster belt that includes Hebei, Henan, Anhui, and Hubei, and five high-density cluster cores that include southern Gansu, Sichuan–Gansu–Shaanxi border area; Guizhou, Hunan, and Chongqing border area; southern Sichuan; and southwest Guizhou. (2) Regarding spatial correlations, the pro-poor tourism villages in central and western regions are in hot spots, while those in eastern regions are in cold spots. The hot spots gradually increase, while cold spots gradually decrease, and the clustering trend of the distribution of the pro-poor tourism villages is increasingly apparent. (3) Pro-poor tourism villages are affected by social, economic, industrial, and other human factors as well as natural geographical factors such as terrain, precipitation, river, and climate, among which the industrial factors have a more significant impact. Pro-poor tourism villages are concentrated in humid mountainous areas with an altitude of about 1000 m and an annual precipitation of more than 800 mm, and they are mostly distributed in the subtropical monsoon climate zone closer to the river and more suitable climate. (4) It is suggested that pro-poor tourism villages can be divided into four types: the resource underutilization type, mountain environment restriction type, traffic location non-optimization type, and industrial development lagging type, and the sustainable development strategies of different types of pro-poor tourism villages are proposed.

Phenolic Compounds from Dendrobium Nobile Lindl.

Dendrobium nobile Lindl.(Orchidaceae), Vietnamese name as Hoang thao dui ga is an epiphytic plant on high tree branches. It grows widely in humid mountainous areas in Vietnam. The plant is used to treat fever, dry mouth, dry throat, increase vitality in traditional medicine. In the course of study on chemical composition of Dendrobium nobile Lindl. in Vietnam, this paper describes the extraction and structure evaluation of five known compounds, including E-1,5-bis(4-hydroxyphenyl)-pent-1-en-3-one (1) together with ferulic acid (2), 4-hydroxy cinnamic acid (3) umbellic acid (4) and 3-(4-hydroxyphenyl) propionic acid (5). The stems of this plant were collected, identified, dried and extracted in different polarity solvents. These substances were isolated from the ethyl acetate and water fractions of methanol extract on the basis of column chromatography. Their structures were identified based on spectroscopic evaluation and comparison of corresponding authentic compounds. This is the first report of compound 1 from the Dendrobium genus.

Effect of Zone and Climate on Yields, Quality and Ripening Characteristics of Montecristo Bananas Grown in Puerto Rico

A study was conducted to determine the effect of zone and climate on yields, ripening characteristics and quality of Montecristo bananas. Experimental plots were established at the Fortuna Substation on the southern coast of Puerto Rico at sea level, and the Adjuntas Substation located in the humid mountainous area at an elevation of 1,800 feet. In plots planted monthly throughout the year, the interval from planting to flowering ranged at the Adjuntas Substation from 371 to 448 days and from 319 to 388 days at the Fortuna Substation. At Fortuna, the length of the flowering period ranged from 120 to 147 days, while at Adjuntas it ranged from 107 to 200 days. A direct relationship was observed at Adjuntas between the length of the flowering period and time of planting. The flowering pattern of the combined monthly plots was different for the two zones. Two flowering cycles were observed at Adjuntas, with the highest percentage of plants flowering from June to December. Although three flowering cycles were observed at Fortuna, the distribution was similar to a normal frequency distribution. Bunch development was much slower at Adjuntas than at Fortuna. The age for harvesting at a given stage of development varied with the time of flowering, but this relationship was more marked at Adjuntas than at Fortuna. The fruit harvested at Adjuntas was quite different in characteristics from the fruit harvested at Fortuna. The bunches were heavier and the fruit weighed more. The bunches also had more hands and more fruit than those harvested at Fortuna. At Adjuntas, the weight of the bunch remained fairly constant throughout the year, while at Adjuntas the weight of the bunch varied with the month of flowering. The weight of the fingers at both locations varied with the time of flowering while the number of fruit per bunch at Fortuna varied only slightly throughout the year. Because the seed material used in these studies was obtained from two farms in the Adjuntas region, another set of experiments was conducted to study the behavior of the Montecristo bananas produced from seed from the experimental plots from each Substation when planted on the other. The results from these experiment showed that the seed material used in our previous studies were of uniform character and that differences observed in flowering patterns, yields, fruit quality and other characteristics were due to the effect of ecological conditions and not to clonal variation. The fruit from both locations when processed into purees gave products of good quality. Fruit from Adjuntas produced purees of a more pronounced yellow color and the flavor was better than fruit from Fortuna. From the standpoint of fresh fruit quality, however, the fruit from Fortuna was better than the fruit from Adjuntas. The fruit from Fortuna had better ripening characteristics, ripening more evenly and with a more attractive yellow color, than the fruit from Adjuntas.

Understanding the hierarchical controls of geographical features on hydrological responses in humid mountainous areas through a stepwise clustering scheme

Understanding the hierarchical controls of geographical features on hydrological responses in humid mountainous areas through a stepwise clustering scheme

Hydrogeochemistry of Fluorine in Groundwater in Humid Mountainous Areas: A Case Study at Xingguo County, Southern China

The understanding of F− concentration in groundwater in humid areas is limited although there are lots of research on high-fluoride groundwater in arid areas. In this paper, with controlling factors of F− concentrations in humid areas as the focus, 130 groundwater samples, obtained from four subsystems in Northwest Xingguo County, Jiangxi Province, China, were investigated to demonstrate the controlling factors of F− concentrations in humid areas. According to analytical results, the following hydrogeochemical characteristics of the fluorine in humid mountainous areas were determined: (1) F− concentration is positively correlated with total dissolved solids (TDS), Ca2+, HCO 3 − , and pH; (2) the groundwater features a high flow rate and low TDS; (3) the equilibrium constant of CaF2 is less than its solubility product constant, and the fluorine-bearing minerals in rocks are in a dissolved state; and (4) the dissolved fluoride-bearing minerals constitute the main sources of F− in the groundwater. Fluorine mainly comes from groundwater fluorine-bearing minerals in metamorphic rocks. Moreover, the low F− concentration in the groundwater mainly results from the fast flow rate of groundwater. Fluoride in groundwater has great potential hazards in humid areas.

Application of Xin'anjiang Model in the flow prediction of ungauged small- and medium-sized catchments in the middle and lower reaches of the Yangtze River Basin

水文资料匮乏流域的洪水预报（PUBs）是水文科学与工程中一个尚未解决的重大挑战.中国湿润山区中小流域大多是水文资料匮乏的流域，在此地区进行洪水预报的重要手段之一就是水文模型参数的估计.对基于参数物理意义的估算方法（以下简称物理估算法）及两种区域化方法进行了研究，将其用于新安江模型参数的估算及移植.皖南山区的29个中小流域被选作水文资料丰富的测量流域，鄂西山区的3个中小流域被视为水文资料匮乏的目标流域，目的是研究目标流域与测量流域空间位置较远但物理条件相似时，区域化等方法是否可以有效估计模型参数.结果表明，即使目标流域与测量流域空间距离较远，区域化及物理估算法也能一定程度上减少参数估计导致的模型效率损失，且在研究区的最优参数估计方案为单流域物理相似法结合回归法及物理估算法.为长江中下游资料匮乏的山区中小流域提出了可行的新安江模型参数估计方案，为该地区的洪水预报提供指导.;Flow prediction in ungauged basins (PUB) is as important as it is difficult. PUB is a major unsolved challenge in scientific and engineering hydrology. So far, empirical and stochastic methods have mainly been used for this purpose. Many small catchments in humid mountainous areas of China are with little or no hydrological data. The principal method of flood forecasting in this area is the parameter estimation of the hydrological model. Xin'anjiang Model was used to predict flow in this study, and Xin'anjiang Model parameters were estimated based on the physical meaning of them and regionalization. Regression and physical similarity approach were included in regionalization methods in this study. The 29 small basins in mountainous areas in southern Anhui Province were selected for gauged catchments, and three small basins in mountainous regions in western Hubei Province were treated as ungauged catchments. The main goal of this approach was to research whether regionalization and other methods could effectively estimate model parameters when the spatial location of the gauged catchments and the ungauged catchments were far away, but the physical conditions were similar. It is shown that:(1) Xin'anjiang Model has high accuracy in flow prediction of study areas. (2) Even if the space distance of gauged catchments and ungauged catchments is far, regionalization and physical-based estimation method can also reduce the efficiency loss caused by parameter estimation to some extent. (3) With the increase in the number of donor catchments, the efficiency of the physical similarity approach is reduced. (4) The optimal parameter estimation scheme in the study area is the ingenious combination of physical similarity approach (only one donor catchment), regression approach and physical-based estimation method. A feasible parameter estimation scheme of the Xin'anjiang Model is proposed in this study, which provides guidance for flow forecasting in small ungauged catchments in humid mountainous areas among the middle and lower reaches of the Yangtze River.

The effects of landscape pattern evolution on runoff and sediment based on SWAT model

To reveal the hydrological effects on changes in land use and landscape pattern of the Wuhua River Basin (hereinafter referred to as the River Basin), this study investigated the upstream of Hezikou Hydrological Station on the Wuhua River; simulated the monthly runoff and sediment yield of the River Basin in a 25-year period (1986–2010) based on the widely used soil and water assessment tool (SWAT) model under the meteorological conditions from 1957 to 2012 and in the context of the landscape change; calculated the change rates in runoff and sediment yield throughout the year and examined the relativity between the rate of change in the runoff and sediment yield and that of land use type composition and landscape pattern using Spearman correlation coefficient. Results revealed the following results. First, the simulation accuracy of runoff and sediment yield based on the SWAT model reached the standard, so the SWAT model was applicable to mesoscale watersheds in hot and humid mountainous areas of southern China. Second, the River Basin was dominated by forest, accounting for around 75% of the whole basin area, followed by cropland, whereas the percentages of built-up land and water body are much lower. With the urbanization and agricultural expansion, a large area of deforestation occurred especially from 1995 to 2005, which potentially resulted in increases of runoff and sediment yield. Third, six typical landscape pattern indices of the River Basin were screened out through the factor analysis. The landscapes of the River Basin under the impact of human activities became fragmented as the spatial heterogeneity increased. Fourth, grassland had the largest soil erosion modulus followed by cropland and built-up land, cropland and forests contributing most to runoff and sedimentation. The changes in runoff and sediment yield mainly occurred near the watershed outlet and upstream in the southern of the river basin, runoff and sedimentation increased significantly in 2005, which are highly likely due to the heavy rain events and deforestation at the time. Fifth, the runoff was significantly affected by the area changes in the cropland and woodland, while the weaker and more insignificant relationship between the changes in landscape pattern indices and that of runoff and sediment yield were observed. Thus, we concluded that the changes in land use have higher and more significant impacts on the runoff and sediment yield in Wuhua River Basin, compared with landscape pattern indices. This work provides useful information for environmental managers to target efforts to reduce soil erosion and related environmental issues effectively. Further research is recommended to integrate climate change and human activities’ impacts on runoff generations and sediment yield processes.

Distribution of wanga plant (piga fettaelata) in South Sulawesi

This study aims to determine the distribution of wanga plants (Piga fettaelata) in South Sulawesi. This data is very important as a baseline for conservation or protection of these species to avoid extinction. The method used is an exploration method by exploring the forest and mountainous areas in South Sulawesi, namely the Latimojong mountain area in Enrekang Regency, in TanaToraja Regency, and in North Toraja Regency. The results showed that the Wanga plants in South Sulawesi were spread in nature in groups with a rather specific habitat that is near water sources, around small rivers, plantations, open fields found on the slopes of hills or former shifting cultivation that get light direct sun, and forest edge. This plant thrives in humid mountainous areas at an altitude of 788 to 1,540 m asl, with an average temperature between 20°C to 25°C.

Analysis of energy consumption improvements of a zero-energy building in a humid mountainous area

The most significant basis for sustainable development, as well as one of the most critical concerns of today's human societies, is energy and how it is consumed. In Iran, about 40% of energy is consumed in residential, commercial, and office buildings. Considering the importance of energy for sustainable development, buildings with zero energy consumption have found a lot of supporters. In the present paper, buildings with zero energy consumption in the north of Iran (Qa'emshahr city) were studied, and the feasibility study for constructing such buildings in this humid mountainous area was done. In this regard, a residential building with a conventional condition was considered as a sample, and energy efficiency parameters were investigated; using different methods, energy consumption of the building was reduced to zero. The research method in this study was based on two principles. At first, using scientific resources, new methods for reducing energy consumption in buildings and how they are managed were researched; in the second step, which is the main part of this paper, using DesignBuilder Software, the energy consumption of the building was determined. In the final step, the power generation capacity and panel area and economic considerations in the payback period were calculated per month. For this purpose, an average of 63 m2 of the solar panel was considered to be the electrical power of the building, which was able to fully produce the building's electricity requirement in 8 months. According to the results, with activities, the amount of electrical energy used for air conditioning in the building has been released by 80% and has been detracted from 34 MW to 7 MW. In the case of return on investment (R0I), to supply the required power generation for the building, it would be possible to receive about 15 000 $per year from the Iranian Ministry of Energy.

Can the use of medicinal plants motivate forest conservation in the humid mountains of Northern Oaxaca, Mexico?

Background. Non-timber forest products are being integrated into conservation strategies. Medicinal plants are considered a reason to conserve the source forests.Question. Can the use of medicinal plants motivate forest conservation?Study site and dates. The study was conducted in Santiago Camotlán, Distrito Villa Alta, Oaxaca, a humid mountainous area in the Sierra Norte of Oaxaca, Mexico, from August 2011 to May 2013.Methods. Ecological Land Units were characterized, and the relative importance of medicinal plants was evaluated. The ethnobotanical methods included participatory mapping, open interviews, semi-structured interviews and free lists with local specialists, as well as members of 17 systematically selected households, collection of characteristic and medicinal plant species, and plant walks with local specialists. For each species, a newly proposed Knowledge, Use and Perception Index based frequency of mention in free lists, frequency of use and perceived importance was calculated.Results. Local people divided their territory primarily by physical geographic characteristics and utilization. Nine units were distinguished: village and roads, home gardens, pastures, cultivated fields (maize, beans, sugar cane and coffee), cloud forest, semi-evergreen tropical forest and evergreen tropical forest, secondary growth ( acahuales ), and riparian vegetation. The most important medicinal plants were Salvia microphylla , Lippia alba and Artemisia absinthium , all cultivated in home gardens; weedy vegetation provided the majority of all medicinal plants. Individuals interested in preserving medicinal species transplanted them into a home garden.Conclusion. For people in the study area, the presence and use of medicinal plants was not a decisive reason for forest conservation.

Immediate effects of prescribed burning in the Central Pyrenees on the amount and stability of topsoil organic matter

Prescribed burning is the deliberate application of fire under selected conditions to accomplish predetermined management objectives. It is generally accepted that controlled use of fire has neutral or even positive effects on soils due to its lower temperature, intensity and severity compared to wildfires. However, very few studies have examined the effects of prescribed burning of shrub vegetation in humid mountain areas on soil properties. The objective of this work was to determine the immediate effects of prescribed burning on the quality and biochemical stability of soil organic matter (SOM) in areas encroached by shrubs in the Central Pyrenees (NE Spain). Soil samples were sampled in triplicate immediately before and after burning from the Ah horizon at 0–1, 1–2 and 2–3cm depths. We quantified the variations as a direct result of burning in (1) the SOM content, (2) the content and mineralization rates of labile and recalcitrant C pools as inferred from incubation assays (141days), and (3) the soil biological activity related to C cycling (microbial biomass C and β-D-glucosidase activity). Nearly all the soil properties studied were significantly affected by fire, varying in terms of extent of the effect and the soil depth affected. The total soil organic C (SOC), C/N ratio, β-D-glucosidase activity, C-CO2 efflux and estimated content of labile SOC decreased significantly up to 3cm depth. The total N and microbial biomass C were significantly affected only in the upper cm of the soil (0–1cm). These results describe a short-term stronger impact of the prescribed fire on topsoil properties than usually reported. However, comparing these findings to other studies should be performed with caution because of the different environments considered in each case, as well as the differing soil thicknesses found in the literature, typically between 5 and 15cm, which can lead to a dilution effect associated with the actual impacts of fire on soil properties. In this sense, the choice of a suitable soil thickness or sampling just after burning can be relevant factors in the detection of the immediate effects of fire. Short- and medium-term monitoring of the soils is needed to assess the suitability of this practice for pasture maintenance and for adapting the frequency of prescribed fires in order to minimize its impact on soil.

How do soil organic carbon stocks change after cropland abandonment in Mediterranean humid mountain areas?

The effects of land use changes on soil carbon stocks are a matter of concern stated in international policy agendas on the mitigation of greenhouse emissions. Afforestation is increasingly viewed as an environmental restorative land use change prescription and is considered one of the most efficient carbon sequestration strategies currently available. Given the large quantity of CO2 that soils release annually, it is important to understand disturbances in vegetation and soil resulting from land use changes. The main objective of this study is to assess the effects of land abandonment, land use change and afforestation practices on soil organic carbon (SOC) dynamics. For this aim, five different land covers (bare soil, permanent pastureland, secondary succession, Pinus sylvestris (PS) and Pinus nigra (PN) afforestation), in the Central Spanish Pyrenees, were analysed. SOC dynamics have been studied in the bulk soil, and in the fractions separated according to two methodologies: (i) aggregate size distribution, and (ii) density fractionation, and rates of carbon mineralization have been determined by measuring CO2 evolution using an automated respirometer. The results showed that: (i) SOC contents were higher in the PN sites in the topsoil (10cm), (ii) when all the profiles were considered no significant differences were observed between pastureland and PN, (iii) SOC accumulation under secondary succession is a slow process, and (iv) pastureland should also be considered due to the relative importance in SOC stocks. The first step of SOC stabilization after afforestation is the formation of macro-aggregates promoted by large inputs of SOC, with a high contribution of labile organic matter. However, our respiration experiments did not show evidence of SOC stabilization. SOC mineralization was higher in the top layers and values decreased with depth. These results gain insights into which type of land management is most appropriate after land abandonment for SOC.

Effects of secondary succession and afforestation practices on soil properties after cropland abandonment in humid Mediterranean mountain areas

Cropland abandonment and subsequent revegetation processes (due to secondary succession and afforestation practices) are global issues with important implications in Mediterranean mountain areas. Several publications have reviewed the impact of cropland abandonment and revegetation on the soil properties dynamics but, so far, limited attention has been paid to Mediterranean humid mountain areas. This paper examines six neighbouring land covers, in the Central Spanish Pyrenees to determine the effects of land covers, cropland abandonment and consequently secondary succession and afforestation practices on soil properties. For this purpose, a total of 85 samples from 6 land covers and from two soil depths were analysed. We observed that changes in soil properties after cropland abandonment were limited, even if afforestation practices were carried out, and no differences were observed between natural succession and afforestation. Land cover and depth had a significant effect on the physical and chemical variables, being larger in the uppermost 0–10cm depth. The organic and inorganic carbon and N concentration, SOC and TN stocks, CN ratio, organic matter, and bulk density showed significant differences. Afforestation improved soil properties, aggregate stability and carbon concentration and stocks when compared to neighbouring bare soils. A soil quality index −based on statistical analysis- suggested that natural forests and Pinus nigra areas developed a higher soil quality rating. Our general results also demonstrated that the impact of disturbance by afforestation techniques (microsites) is difficult to discern. The differences found with respect to the native forest appear to indicate that the afforested soils have not yet reached their maximum soil quality and maximum potential as soil organic carbon sink. As there was no difference found between the soil improvement by natural succession in comparison to afforestation, these results put the question forward which type of forest and landscape management is most appropriate to decide for the best practices after cropland abandonment for soil recovery and erosion control.

小河沟水文站产汇流特性分析

本文根据流域内实测暴雨洪水资料，分析小河沟水文站、马鹿塘、太阳寨等5个雨量站的暴雨特性(均具有暴雨强度大、历时短、笼罩面积小等特点)，结合流域内暴雨时空分布规律，依据下垫面条件，采用蓄满产流机制分析产流，推理过程线法分析汇流，并用小河沟水文站实测暴雨洪水资料进行检验，通过曲线精度评定，结果表明：蓄满产流机制在热带湿润山区是适用的，产汇流参数具有规律性，可供相似流域无资料地区移用或参考。 According to the information of the rainstorm and flood measured in river basin, the features of rainstorm in five precipitation stations which are Xiaohegou hydrologic station, Malutang and Taiyangzhai and other two stations are analyzed, and the features are high intensity, short duration and small area covered by rainstorm. Based on space-time distribution pattern and the condition of underlying surface, I apply the runoff yield under saturated storage to analyze runoff yield and apply the reasoning process to analyze junctions, use the information of the rainstorm and flood of Xiaohegou hydrologic station to examine, and use curve precision to do evaluation. The results show: the runoff yield under saturated storage is suitable for the use in tropical and humid mountainous area. Runoff yield and concentration parameters have its regularity, and similar river basins or areas without the information could use the conclusion or use it as a reference.

Effectiveness of Rainwater Harvesting in Runoff Volume Reduction in a Planned Industrial Park, China

It is urgent to effectively mitigate flood disasters in humid mountainous areas in southeastern China for the increasing flood risk under urbanization and industrialization. In this study, a rural district with an area of 13.39 km2 that planning to build an industrial park covering an area of 7.98 km2 in Changting was selected to estimate the potential of collectable rainwater and the extent to which runoff volume can potentially be mitigated by rainwater harvesting. In addition, the optimum cistern capacity of a rainwater harvesting system in the planned industrial park was evaluated using daily water balance simulation and cost-efficiency analysis. The results showed that rainwater harvesting in the planned industrial park has great potential. The annually collectable rainwater is approximately 9.8 × 106 m3 and the optimum cistern capacity is determined to be 0.9 × 106 m3. With the optimum cistern capacity, the annual rainwater usage rate is 0.99, showing neither financial savings nor deficits. Rainwater harvesting can reduce 100 % of runoff volume in the cases of critical rainfall storm (50 mm) and annual average maximum daily rainfall (111.2 mm), and 58 % of runoff volume in the case of maximum daily rainfall (233.6 mm), respectively. All surface runoff can be collected and stored in the cisterns when rainfall amount is less than 135.5 mm in a rainstorm event.

Salamandra salamandra (Amphibia: Caudata: Salamandridae) in Portugal: not all black and yellow

The fire salamander complex is quite diverse in the Iberian Peninsula where nine subspecies of Salamandra salamandra are currently recognized. Here, we analysed the geographical distribution of the subspecies S. s. gallaica and S. s. crespoi using partial sequences of the mitochondrial cytochrome b gene of 168 individuals from 12 locations in Portugal. Our results support the existence of a deep lineage divergence between the two subspecies, with non-overlapping geographical distributions except in two contact zones: one in Sesimbra on the western coast, and another in Alcoutim on the southeastern border with Spain. Moreover, S. s. crespoi displays signs of gene flow among the sampled locations whereas S. s. gallaica shows evidence of some restriction to gene flow. Present-day genetic make-up of S. s. gallaica and S. s. crespoi is a result of past historical events, fine-tuned by contemporary Iberian geoclimate. Humid mountain areas were found to harbour increased genetic diversity possibly acting as past refugia during drier interglacial periods. To analyse wider geographical patterns and lineage splitting events within S. salamandra we performed a Bayesian dating analysis completing our data set with previously published sequences. The observed divergences were associated to successive biogeographic scenarios, and to other Iberian species showing similar trends.

The Climatic Signature of Incised River Meanders

Climate controls landscape evolution, but quantitative signatures of climatic drivers have yet to be found in topography on a broad scale. Here we describe how a topographic signature of typhoon rainfall is recorded in the meandering of incising mountain rivers in the western North Pacific. Spatially averaged river sinuosity generated from digital elevation data peaks in the typhoon-dominated subtropics, where extreme rainfall and flood events are common, and decreases toward the equatorial tropics and mid-latitudes, where such extremes are rare. Once climatic trends are removed, the primary control on sinuosity is rock weakness. Our results indicate that the weakness of bedrock channel walls and their weakening by heavy rainfall together modulate rates of meander propagation and sinuosity development in incising rivers.

Soil n‐alkane δ13C along a mountain slope as an integrator of altitude effect on plant species δ13C

Carbon isotopic compositions of leaf wax‐derived n‐alkanes (δ13Cwax) and bulk organic matter (δ13CSOM) in surface soils from ca. 1000 to 3800 m above sea level along Mount Gongga, China were investigated for their altitudinal variations. There is a breakpoint, suggesting a precipitation threshold, at 2050 m in both δ13Cwax and δ13CSOM trends. Above the threshold, δ13Cwax and δ13CSOM increase in a similar pattern of the average species‐level response to altitude reported from various humid mountainous areas. However, a significant decreasing trend with altitude occurs below the threshold, within which climate changes upward from arid to humid, consistent with plant foliar δ13C response to precipitation at water‐limited areas. Because δ13Cwax and δ13CSOM naturally integrate plant species and time, this work demonstrates that the altitude‐induced environmental impact on plant species‐level δ13C has been conveyed to soils, and that the species‐level δ13C could be linearly scaled up to the community level.