Moderate Rocky Desertification Research Articles

Soil Microbial Communities in Pseudotsuga sinensis Forests with Different Degrees of Rocky Desertification in the Karst Region, Southwest China

Rocky desertification (RD), a natural and human-induced process of land degradation in karst areas, has become the primary ecological disaster and one of the obstacles to sustainable ecological development in southwest China. Nevertheless, the variation of soil physical and chemical properties, bacterial and fungal communities, and their relationships in RD forests remains limited. Therefore, soil samples were collected from forests under four degrees of RD (NRD, non-RD; LRD, light RD; MRD, moderate RD; and SRD, severe RD) and subjected to high-throughput sequencing of 16S rRNA and ITS1 genes. The results showed a significant reduction in bacterial richness and diversity, while fungal richness and diversity decreased markedly and then showed a balanced trend with the increase in RD degree, indicating that bacteria and fungi did not present the same dynamics in response to the process of RD. The bacterial communities were dominated by Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi, while the fungal communities were dominated by Basidiomycota, Ascomycota, and Mortierellomycota. The PCoA and NMDS demonstrated significant differences in microbial communities in study sites, among which the fungal communities in non-RD forest and LRD forest clustered together, suggesting that fungal communities were more stable than bacteria in RD forest. The db-RDA, Mantel test, and random forest model confirmed the important role of soil BD, pH, SOC, AN, and AP in driving microbial diversity and communities. The IndVal analysis suggested that Chloroflexi, Patescibacteria, Atheliales, and Cantharellales with high indicator values were identified as potential bio-indicators for RD forests. This study could not only improve our understanding of bacterial and fungal community dynamics across RD gradients, but also could provide useful information for the further use of microorganisms as indicators to reflect the environmental changes and ecosystem status during forest RD.

Community Structure of Epilithic Moss Mites and Their Response to Environmental Factors in Different Grades of Rocky Desertification Habitats

This research has been undertaken to reveal the changes in the community structure of epilithic moss mites and the response of these mites to environmental factors under different grades of rocky desertification environment. In this study, epilithic moss mites were collected in a demonstration area for rocky desertification management in Bijie Salaxi, with the following rocky desertification grades as habitat gradients: without rocky desertification, potential rocky desertification, light rocky desertification, moderate rocky desertification, and severe rocky desertification. The differences in the number of individuals, taxa, diversity index, dominance index, richness index, evenness index, and the effects of environmental factors on moss mite communities were revealed by one-way ANOVA, correlation analysis, and redundancy analysis for different grades of these mites. The results show that a total of 11,563 epilithic moss mites were captured in the study area, belonging to three orders, 100 families, and 171 genera, with Nanorchestes and Trichogalumna as the dominant taxa. With the deepening of rocky desertification, the dominant number of Nanorchestes and Trichogalumna increased. Still, the percentage of very rare genera also decreased, and there were differences in the composition of the dominant genus taxa in different grades of rocky desertification. Different grades of rocky desertification habitats had significant effects on the diversity index and richness index of moss mite species but not on the number of taxa, individuals, dominance index, and evenness index. The overall epilithic moss mite communities in different habitats were moderately dissimilar. Air temperature and rock temperature had strong effects on each index of moss mite diversity, whereas light factors and air humidity had a weak impact on these indices. Amongst the communities, those of Scheloribates are more sensitive to rock temperature variation, while Blattisocius, Ledermuelleria and Camerobia correlate more with a light variation. Parholaspulus, Blattisocius, Camerobia, Haplochthonius, Gymnodamaeus, etc. were more sensitive to changes in air humidity. The research shows that there are differences in moss mite community structure under different rocky desertification grades, rocky desertification has caused some effects on moss mite community structure, and the use of mite dominant taxa genera can give preliminary indications of the rocky desertification environment; meanwhile, there is a specific correlation between mite taxa and habitat environment changes.

Soil Quality Assessment and Management in Karst Rocky Desertification Ecosystem of Southwest China

Karst rocky desertification is a common phenomenon in terrestrial ecosystems, and the deterioration of soil quality has a serious side effect on the aboveground vegetation and underground environmental factors. To clarify the variety of soil quality in different rocky desertification grades in typical karst areas of southwest China, the soil quality of four rocky desertification grades was calculated by a single model (SQI: soil quality index), two screening processes (TDS: total dataset and MDS: minimum dataset) and three scoring methods (SSF: standard scoring function, SL: linear scoring function and SNL: nonlinear scoring function). The key results are as follows: Significant differences were found in the soil environment factors in non-rocky desertification (NRD), light rocky desertification (LRD) and moderate rocky desertification (MRD) as compared to intense rocky desertification (IRD) (p < 0.01). Except for total potassium (TK), manganese (Mn) and amylase, the other soil environmental factors showed U-shaped changes. In contrast, TK, Mn and amylase increased first and then decreased. Additionally, the SQI based on MDS in SSF, SL and SNL was IRD (0.58) > NRD (0.48) > LRD (0.45) > MRD (0.43), IRD (0.53) > NRD (0.42) > LRD (0.39) > MRD (0.36) and IRD (0.57) > NRD (0.47) > MRD (0.42) > LRD (0.40), respectively. However, the SQI was always in the trend of IRD > NRD > MRD > LRD based on the TDS. Overall, although the soil area is scarce, the edaphic properties, enzyme activities and soil quality are not poor in the IRD. Furthermore, we found that SNL was more suitable for the evaluation of soil quality in the karst rocky desertification area (R2 = 0.63, p < 0.001 and the coefficient of variation = 30.69%). This research helps to clarify the variation in soil properties and quality during the succession of rocky desertification and provides guidelines for the sustainable management of soil quality in areas of southwest China.

The Changes of Spatiotemporal Pattern of Rocky Desertification and Its Dominant Driving Factors in Typical Karst Mountainous Areas under the Background of Global Change

There are significant differences in the dominant driving factors of rocky desertification evolution in different historical periods in southwest karst mountainous areas. However, previous studies were mostly conducted in specific periods. In this study, taking Bijie City as an example, the spatial and temporal evolution pattern of rocky desertification in Bijie City in the recent 35 years was analyzed by introducing the feature space model and the gravity center model, and then the dominant driving factors of rocky desertification in the study area in different historical periods were clarified based on GeoDetector. The results were as follows: (1) The point-to-point B (bare land index)-DI (dryness index) feature space model has high applicability for rocky desertification monitoring, and its inversion accuracy was 91.3%. (2) During the past 35 years, the rocky desertification in Bijie belonged to the moderate rocky desertification on the whole, and zones of intensive and severe rocky desertification were mainly distributed in the Weining Yi, Hui, and Miao Autonomous Region. (3) During 1985–2020, the rocky desertification in Bijie City showed an overall weakening trend (‘weakening–aggravating–weakening’). (4) From 1985 to 2020, the gravity center of rocky desertification in Bijie City moved westward, indicating that the aggravating degree of rocky desertification in the western region of the study area was higher than that in the eastern region. (5) The dominant factors affecting the evolution of rocky desertification in the past 35 years shifted from natural factor (vegetation coverage) to human activity factor (population density). The research results could provide decision supports for the prevention and control of rocky desertification in Bijie City and even the southwest karst mountainous area.

Spectral analysis of seasonal rock and vegetation changes for detecting karst rocky desertification in southwest China

Karst rocky desertification (KRD) has become a major long-term problem for the ecological environment in karst areas of southwest China. The aim of this study was to monitor and evaluate the level of rocky desertification in Pingguo County, Guangxi Province, southwest China, by tracking the seasonal spectral changes in rock and vegetation cover. Landsat-8 Operational Land Imager (OLI) images and field measurements of karst areas were collected and a novel karst rocky desertification index (KRDI) was constructed as an indicator of rocky desertification based on greenness, humidity, and brightness. Then, the time-spectrum feature space (TSFS) model was used to determine the level of rocky desertification. The main findings were as follows. (1) KRDI is a good indicator of karst rocky desertification; the highest KRDI value was obtained for severe rocky desertification, followed by moderate rocky desertification, with slight rocky desertification exhibiting the lowest KRDI value. (2) KRDI values exhibited some differences in different seasons, with the lowest KRDI occurring in summer and the highest in winter. (3) The TSFS model can accurately monitor and identify different levels of rocky desertification. The selected key indicators performed well, with a Kappa coefficient of 0.90 and overall accuracy of 0.92. Therefore, the proposed index, combining spectral information with spatiotemporal information, is a promising method for extracting information on karst rocky desertification, with significant application potential for areas with similar geology.

喀斯特地区不同石漠化程度草地根系分解与周转特征

为探明喀斯特地区不同草地根系动态及其对石漠化的响应，本文以3种不同石漠化程度（潜在、中度和强度）的草地为研究对象，采用连续根钻法和分解袋法，于2017年3月-2018年1月，分析了不同石漠化草地的根系垂直分布、季节动态、分解、周转及其与土壤因子的关系。结果表明，3种石漠化草地的根系生物量随着土层的深度增加呈逐渐降低的趋势，潜在和中度石漠化草地的根系生物量均呈现明显的单峰型季节变化，强度石漠化草地的根系生物量变化不显著。3种石漠化草地的根系分解速率受土壤有机碳、全钾、全氮、含水量、电导率、温度等的影响显著，随分解时间均表现为"快-慢-快"的变化趋势，根系的年分解率分别为64%、56%和58%。3种草地根系完全分解（分解率为95%）时，分别需要1174天、1351天和1878天。随石漠化程度的加剧，3种草地的根系周转速率呈逐渐降低的趋势，分别为1.70次/a、1.36次/a和0.87次/a。;Rocky desertification is a major kind of land desertification. The degradation land of karst rocky desertification is one of the most serious problems on economic development, ecosystem restoration and reconstruction in Southwest China. Grassland is one of the main vegetation types in karst region of Guizhou, its root is sensitive to the response of to environmental conditions, which determines the growth and development of plants and soil nutrition status. Root dynamics also has an indicator effect on environmental changes, and can reflect the health status of grassland ecosystem. As the intermediary connecting the aboveground and underground parts of vegetation, root plays an important role in the matter exchange and energy transfer between plants and soil, root decomposition and turnover contributes significantly to element cycling in grassland ecosystems. In order to identify the root dynamics and their response to rocky desertification in different grasslands in the karst region, this paper took three different rocky desertification grasslands (potential rocky desertification grasslands, moderate rocky desertification grasslands, and intensity rocky desertification grasslands) as research objects. The continuous soil drilling method and root bag method were used to investigate the monthly root dynamic, root production and turnover from March 2017 to January 2018. The results show that the root biomass of the three rocky desertification grasslands decreased gradually with the depth of soil, root biomass in the 0-10 cm soil layer accounted for more than 57% of the total biomass in the 0-30 cm soil layer. The root biomass of potential and medium rocky desertification grasslands showed significantly seasonal variation of single-peak, and the root biomass of the severely rocky desertification grassland was not significant. The root decomposition rate all showed the ″fast-slow-fast″ status, was significantly influenced by soil organic carbon, total potassium, total nitrogen, soil water content, soil electrical conductivity, soil temperature in the three rocky desertification grasslands. When the complete decomposition rate reached 95%, 1174, 1351 and 1878 days were needed in the three grasslands, respectively. With the intensifying of rocky desertification, the root turnover rate decreased gradually, and were 1.70 times/year, 1.36 times/year, and 0.87 times/year in the three grasslands, respectively. The above conclusions provide an important scientific basis for a deeper understanding of the nutrient cycle, soil fertility maintaining and the restoration of rocky desertification grasslands. It is necessary to strengthen the research on the nutrient release mechanism of the root in rocky desertification grassland in Southwest China.

Research on Inversion of Soil Moisture in Karst Area Based on Full-Polarization SAR Data

In order to select a reasonable controlling mode of rocky desertification and restrain the development of rocky desertification with local conditions, the soil moisture in Karst area was studied by using full-polarization Synthetic Aperture Radar (SAR) data in this paper. Based on the decisive role of rocky desertification degree, vegetation, slope and characteristic of the soil, different models were employed to invert the soil moisture in different rocky desertification degree areas according to their land use type and vegetation as follows: (1) The advanced integral equation model (AIEM) was employed in the intensive rocky desertification and serious rocky desertification areas. (2) The water-cloud model (WCM) coupled with AIEM was employed in the slight rocky desertification and moderate rocky desertification areas. (3) The Michigan microwave canopy scattering (MIMICS) model coupled with AIEM was employed in the non-rocky desertification and potential rocky desertification areas. As a result, the soil moisture was inverted successfully in the whole study area with the total inversion accuracy of 84.37% and RMSE of 2.10. This result demonstrates that the proposed method can invert the soil moisture accurately and provide a powerful technical support for inverting the soil moisture in the Karst area with large span, fluctuating landform and diverse vegetation.

δ13C values of soil organic carbon and their responses to C3 and C4 plants shift in Mengzi karst graben basin, SW China

Understanding the controlling factors of soil organic carbon isotope (δ13CSOC) change and the vegetation succession process is crucial to guide ecological restoration and agricultural cultivation in karst rocky desertification region. However, the information about the combination of C3 and C4 plant distribution and rocky desertification remains unknown. Soils from different landforms, including basin, slope, and plateau, were sampled to investigate the spatial variance of the δ13CSOC distribution characteristics. The contribution of C3 and C4 plant species for δ13CSOC under the different rocky desertification grades (LRD: light rocky desertification; MRD: moderate rocky desertification; and SRD: severe rocky desertification) in Mengzi karst graben basin of Southwest (SW) China was also discussed. The δ13CSOC value decreased with the increase of altitude from basin, slope to plateau. At the same landform, different rocky desertification grades had no significant effect on the δ13CSOC in slope and plateau. Nevertheless, there were significant differences of δ13CSOC C between LRD and SRD in the basin. The C4 plants account for more than 70% in the basin and slope, while C3 plants account for more than 70% in the plateau. This may be due to the long-term cultivation of corn in the historical period in the basin and slope. However, the plateau area is not suitable for the growth of C4 plants such as corn due to the cold climate. In addition, in the same landform, with the aggravation of rocky desertification, the proportion of C4 plants for δ13CSOC increased with the proportion of C3 plants decreased. With the aggravation of rocky desertification, the composition of vegetation species changed from arbour (C3 plants) to small shrubs and herbs (C4 plants).

The soil properties and their effects on plant diversity in different degrees of rocky desertification

Rocky desertification is a process of soil erosion and vegetation destruction. On the surface, the landscape of rocky desertification is similar to that of desertification, which has a negative impact on the social and economic development of Southwest China. To clarify the influence of soil properties on plant diversity in rocky desertification areas, three grades of rocky desertification in Southwest Hunan Province were selected: light rocky desertification (LRD), moderate rocky desertification (MRD) and intense rocky desertification (IRD). Soil pH, soil organic carbon (SOC), N, P, K, Ca, Mg were measured, and the species compositions of herbs and shrubs were investigated. The effects of soil properties on plant diversity were studied by using redundancy analysis (RDA). The results showed that except soil pH and Ca, which increased with rocky desertification grade, the soil component contents were MRD > LRD > IRD. The species richness of shrubs was higher than that of herbs, and the difference was significant in MRD. The diversity of herbs first decreased and then increased, and the distribution became increasingly uniform. By contrast, shrub diversity exhibited an opposing distribution trend. RDA analysis showed that the soil nutrient content differed significantly among the rocky desertification grades. Among the nutrients analysed, N, P and K were the main factors affecting species composition in the rocky desertification areas, and their distribution characteristics partly explained the uneven distributions of herbs and shrubs.

Preliminary Characterization of Underground Hydrological Processes under Multiple Rainfall Conditions and Rocky Desertification Degrees in Karst Regions of Southwest China

Karst regions are widely distributed in Southwest China and due to the complexity of their geologic structure, it is very challenging to collect data useful to provide a better understanding of surface, underground and fissure flows, needed to calibrate and validate numerical models. Without characterizing these features, it is very problematic to fully establish rainfall–runoff processes associated with soil loss in karst landscapes. Water infiltrated rapidly to the underground in rocky desertification areas. To fill this gap, this experimental work was completed to preliminarily determine the output characteristics of subsurface and underground fissure flows and their relationships with rainfall intensities (30 mm h−1, 60 mm h−1 and 90 mm h−1) and bedrock degrees (30%, 40% and 50%), as well as the role of underground fissure flow in the near-surface rainfall–runoff process. Results indicated that under light rainfall conditions (30 mm h−1), the hydrological processes observed were typical of Dunne overland flows; however, under moderate (60 mm h−1) and high rainfall conditions (90 mm h−1), hydrological processes were typical of Horton overland flows. Furthermore, results confirmed that the generation of underground runoff for moderate rocky desertification (MRD) and severe rocky desertification (SRD) happened 18.18% and 45.45% later than the timing recorded for the light rocky desertification (LRD) scenario. Additionally, results established that the maximum rate of underground runoff increased with the increase of bedrock degrees and the amount of cumulative underground runoff measured under different rocky desertification was SRD > MRD > LRD. In terms of flow characterization, for the LRD configuration under light rainfall intensity the underground runoff was mainly associated with soil water, which was accounting for about 85%–95%. However, under moderate and high rainfall intensities, the underground flow was mainly generated from fissure flow.

2004-2016年贵州省石漠化状况及动态演变特征

石漠化是制约我国西南地区社会、经济、生态发展的重要因素之一，及时监测评估其演变状况，对区域石漠化防治及生态环境建设具有重要科学意义。选取2004-2016年间4期TM影像，研究贵州省域尺度上、石漠化时空演变特征和未来发展趋势。结果显示：1）2004-2016年间，贵州省78.3%的区域植被覆盖度上升，平均增加了19.1%，达到63.4%，有55.4%的区域岩石裸露率下降；2）贵州省石漠化空间分布呈现从东北到西南渐次加重的特征，西部毕节市中、重度石漠化面积占该区域面积仍达62.0%-86.4%，而东部黔东南州约为18.4%-33.0%；3）2004-2016年间，贵州省石漠化状况呈现总体持续好转态势，以轻、中度石漠化转入为主体的无石漠化面积增加了1.1倍，轻度石漠化增加了20.0%左右，中度和重度石漠化面积分别减少了40.0%左右；4）截止到2016年，贵州省无石漠化、轻、中、重度石漠化区域分别占比约42.0%、24.1%、23.5%、10.4%；5）未来2020年及2024年，贵州省石漠化仍将持续改善，石漠化面积占比将分别减少8.9%和12.2%。过去十多年间，贵州省石漠化状况得到基本遏制，但局部区域仍存在高度的不稳定性，或趋于恶化的风险，未来在各类政策措施的支持下，贵州省石漠化状况仍将继续好转，但部分重度石漠化区域的治理将更为复杂而艰难。;The rock desertification is one of the important factors restricting the development of social, economic and ecology in Southwest China. Timely monitoring and evaluation have great scientific significance for the prevention and control of regional rock desertification and the construction of the ecological environment. In this study, the TM image of four periods from 2004 to 2016 were selected for evaluating the dynamic evolution of rocky desertification in the region of Guizhou Province. The results showed: 1) The vegetation coverage Province went up in 78.3% of Guizhou, with an average of 19.1% to 63.4%, but bare rock rate decreased in 55.4% of this region between 2004 and 2006. 2) The spatial distribution of rocky desertification in Guizhou Province presents the characteristics of gradual aggravation from northeast to southwest. The areas of moderate and severe rocky desertification in Bijie City western Guizhou Province still accounted for 62.0%-86.4%, while in Qiandongnan eastern Guizhou Province, it was only 18.4%-33.0%. 3) From 2004 to 2016, the situation of rocky desertification in Guizhou Province showed a general trend of continuous improvement. The area nil-rocky desertification increased by 1.1 times, deriving from the transition of light and moderate rocky desertification mainly, The slight rocky desertification increased by around 20.0%, and the moderate and severe rocky desertification decreased by around 40.0% respectively. 4) By the end of 2016, the areas of nil-rock desertification, light rock desertification, medium and severe rock desertification in Guizhou Province accounted for about 42.0%, 24.1%, 23.5%, and 10.4% respectively. 5) In 2020 and 2024, the rock desertification would continue to be improved in Guizhou Province, and the areas of rock desertification would decrease by 8.9% and 12.2% respectively. In the past decade or more, the satuation of rock desertification in Guizhou Province has been basically contained, but there was still a high degree of instability or risk of deterioration in some regions. In the future, with the support of various policies and measures, the situation of rock desertification in Guizhou Province will continue to improve, but the controlling of some severe rocky desertification areas will be more complicated and difficult.

The Characteristics of Soil C, N, and P Stoichiometric Ratios as Affected by Geological Background in a Karst Graben Area, Southwest China

Understanding ecological stoichiometric characteristics of soil nutrient elements is crucial to guide ecological restoration and agricultural cultivation in karst rocky desertification region, but the information about the effect of the geological background on ecological stoichiometric ratios remains unknown. Soils from different landforms, including a basin, slope, and plateau, were sampled to investigate the spatial variance of the ecological stoichiometric characteristics of soil carbon (C), nitrogen (N), and phosphorus (P) under different rocky desertification grades (LRD: light rocky desertification; MRD: moderate rocky desertification; and SRD: severe rocky desertification) in a karst graben basin of Southwest China. Soil C:N ratio was not significantly influenced by rocky desertification grade, which was at a relatively stable level in the same landform, but soil C:P and N:P ratios increased with increasing rocky desertification grade. This change was consistent with increased soil organic carbon (SOC) and total nitrogen (TN) concentrations in the same geomorphic location along with the intensification of rocky desertification, but soil P concentration remained at a relatively stable level, indicating that P may be the limiting macronutrient for plant growth during vegetation restoration in a karst graben area. The soil C:N ratio of slope land was larger than that of the basin and plateau, while the soil C:P ratio and N:P ratio of the slope and plateau were significantly larger than that of the basin. The correlations between pH and C, N, and P stoichiometry decreased significantly when Ca was used as a control variable. In sharp contrast, the correlations between Ca and C, N, and P stoichiometry were highly significant no matter whether pH was used as a control variable, suggesting the important role of Ca in soil C, N, and P stoichiometry in karst graben basins.

植被恢复模式对石漠化生态系统碳储量的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 植被恢复模式对石漠化生态系统碳储量的影响 DOI: 10.5846/stxb201806051267 作者: 作者单位: 中国林业科学研究院热带林业实验中心,广西友谊关森林生态系统定位观测研究站;中国林业科学研究院热带林业实验中心,广西友谊关森林生态系统定位观测研究站;中国林业科学研究院热带林业实验中心,中国林业科学研究院森林生态环境与保护研究所,中国林业科学研究院热带林业实验中心,广西友谊关森林生态系统定位观测研究站;中国林业科学研究院热带林业实验中心,广西友谊关森林生态系统定位观测研究站;中国林业科学研究院热带林业实验中心,中国林业科学研究院热带林业实验中心 作者简介: 通讯作者: 中图分类号: 基金项目: 国家国际科技合作专项项目（2015DFA31440） Effect of vegetation restoration patterns on the carbon storage in a rocky desertification ecosystem Author: Affiliation: Experimental Center of Tropical Forestry, Chinese Academy of Forestry,,,,,,, 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:为揭示石漠化生态系统碳储量对植被恢复模式的响应，在广西天等县中度石漠化山地，研究了吊丝竹纯林（Dendrocalamus minor D）、任豆纯林（Zenia insignis Z）、任豆、蚬木（Buerretiodendron hsienmu）和顶果木（Acrocarpus fraxinifolius）混交林（mixed plantation M），以及相应同龄封育林（DCK、ZCK、MCK）的碳储量。结果表明：人工林碳储量显著高于相应同龄封育林的碳储量，D、Z、M人工林碳储量分别为67.75、66.56、121.20 t/hm2，而DCK、ZCK、MCK封育林仅为49.75、52.89、60.86 t/hm2。碳储量在乔木层、地被物层、土壤层分配排序因生态系统类型而异，如M：乔木层 > 土壤层 > 地被物层；D和Z：土壤层 > 乔木层 > 地被物层；DCK、ZCK和MCK：土壤层>地被物层>乔木层。此外，M、D、Z乔木层年平均碳储量差异显著，而封育林尚未形成乔木层，其植被碳储量则随封育时间的增加而提高，即MCK > ZCK > DCK。可见，在中度石漠化山地，植被恢复模式显著影响生态系统碳储量及其分配。人工造林相对于封山育林更能快速促进植被恢复、形成乔木林，从而提高生态系统碳储量。 Abstract:To explore the responses of carbon storage to different vegetation restoration patterns in a rocky desertification ecosystem in Tiandeng County, Guangxi, we selected pure plantations of Dendrocalamus minor (D) and Zenia insignis (Z), a mixed plantation (M) of Z, Buerretiodendron hsienmu (B) and Acrocarpus fraxinifolius (A), as well as their corresponding closed forests (DCK, ZCK, MCK) with same ages to determine the carbon storage. Our results showed that the carbon storages of pure and mixed plantations were significantly higher than those of the corresponding closed forests, (P < 0.05), since the carbon storages of D, Z, and M plantations were 67.75, 66.56, and 121.20 t/hm2, seperately, whereas those of DCK, ZCK, and MCK were only 49.75, 52.89, and 60.86 t/hm2, respectively. The orders of carbon storage in the layers of tree, ground cover, and soil varied with the ecosystem types. For example, in M:tree layer > soil layer > ground cover layer; in D and Z plantations:soil layer > tree layer > ground cover layer; in DCK, ZCK, and MCK: soil layer > ground cover layer > tree layer. Additionally, the annual average carbon storage of the tree layer was significantly different among M, D, and Z (P < 0.05). However, the enclosed forests did not form arboreal forest and the carbon storage of vegetation increased with enclosure time (MCK > ZCK > DCK). This study suggests that different vegetation restoration patterns can significantly affect the carbon storage and its allocation in the moderate rocky desertification ecosystem, and afforestation is a more effective way to improve the vegetation restoration, form arboreal forests, and further increase the ecosystem carbon storage, compared to the closed forest. 参考文献 相似文献 引证文献

Change of community structure of soil mites in the early stage of ecological restoration in moderate rocky desertification of Karst area, Guizhou Province, China.

The monitoring of soil mite community is an important part of ecological restoration monitoring. Changes of community structure in soil mites could reflect effects of ecological restoration in degraded environment. In different seasons of 2014, we investigated soil mites in the moderate rocky desertification ecological restoration area of Chaoying small watershed in Bijie City, Guizhou Pro-vince. We compared the community structure of soil mites in native Quercus variabilis forest and moderate rocky desertification area. The results showed that soil mites in ecological restoration area of moderate rocky desertification belonged to three orders, 35 families, and 58 genera, with Haploze-tes and Vilhenabates being the dominant genera. Higher number of genera, abundance, and indivi-dual densities were found in upper soil layer. The community structure of predatory Gamasina mites was mainly r-selected, and that of Oribatida mites was mainly Poronota (P-type). In the moderate rocky desertification ecological restoration area, both the abundance and individual density of soil mites were higher than that in moderate rocky desertification area and Q. variabilis forest, while the number of genera, diversity index and richness index were higher than that in moderate rocky desertification area, but lower than that in Q. variabilis forest. On the basis of the control area, 32 genera of mites were recovered and added, accounting for 55.2% of the total number of mite genera in the restoration area. In the whole study area, the number of mite genera were significantly correlated with soil available potassium, richness index, and organic carbon content. The number of indivi-duals, individual density, diversity index, richness index separately had significant correlations with the content of available potassium. The richness index had significant correlation with the content of organic matter. Our results suggested that the vegetation restoration of rocky desertification was beneficial to the restoration of mite community and improvement of soil environment, and that the dominant groups, new groups, and restoration groups of soil mites could indicate environment changes. However, the relationships between soil mite community structure and vegetation, soil physical and chemical factors in the restoration area remained to be further studied.

Evaluation of Water Resource Security Based on an MIV-BP Model in a Karst Area

Evaluation of water resource security deserves particular attention in water resource planning and management. A typical karst area in Guizhou Province, China, was used as the research area in this paper. First, based on data from Guizhou Province for the past 10 years, the mean impact value–back propagation (MIV-BP) model was used to analyze the factors influencing water resource security in the karst area. Second, 18 indices involving five aspects, water environment subsystem, social subsystem, economic subsystem, ecological subsystem, and human subsystem, were selected to establish an evaluation index of water resource security. Finally, a BP artificial neural network model was constructed to evaluate the water resource security of Guizhou Province from 2005 to 2014. The results show that water resource security in Guizhou, which was at a moderate warning level from 2005 to 2009 and a critical safety level from 2010 to 2014, has generally improved. Groundwater supply ratio, industrial water utilization rate, water use efficiency, per capita grain production, and water yield modulus were the obstacles to water resource security. Driving factors were comprehensive utilization rate of industrial solid waste, qualifying rate of industrial wastewater, above moderate rocky desertification area ratio, water requirement per unit gross domestic product (GDP), and degree of development and utilization of groundwater. Our results provide useful suggestions on the management of water resource security in Guizhou Province and a valuable reference for water resource research.

Calcium content and high calcium adaptation of plants in karst areas of southwestern Hunan, China

Abstract. Rocky desertification is a major ecological problem of land degradation in karst areas. In these areas, the high soil calcium (Ca) content has become an important environmental factor that can affect the restoration of vegetation. Consequently, the screening of plant species that can adapt to high Ca soil environments is a critical step in vegetation restoration. In this study, three grades of rocky desertification sample areas were selected in karst areas of southwestern Hunan, China (LRD: light rocky desertification; MRD: moderate rocky desertification; and IRD: intense rocky desertification). Each grade of these sample areas had three sample plots in different slope positions, each of which had four small quadrats (one in rocky-side areas, three in non-rocky-side areas). We measured the Ca content of leaves, branches, and roots from 41 plant species, as well as soil total Ca (TCa) and exchangeable Ca (ECa) at depths of 0–15, 15–30, and 30–45 cm in each small quadrat. The results showed that the soil Ca2+ content in rocky-side areas was significantly higher than that in non-rocky-side areas (p&lt;0.05). The mean soil TCa and ECa content increased gradually along with the grade of rocky desertification, in the order IRD &gt; MRD &gt; LRD. For all plant functional groups, the plant Ca content of aboveground parts was significantly higher than that of the belowground parts (p&lt;0.05). The soil ECa content had significant effects on plant Ca content of the belowground parts but had no significant effects on plant Ca content of the aboveground parts. Of the 41 plant species that were sampled, 17 were found to be dominant (important value &gt; 1). The differences in Ca2+ content between the aboveground and belowground parts of the 17 dominant species were calculated, and their correlations with soil ECa content were analyzed. The results showed that these 17 species can be divided into three categories: Ca-indifferent plants, high-Ca plants, and low-Ca plants. These findings provide a vital theoretical basis and practical guide for vegetation restoration and ecosystem reconstruction in rocky desertification areas.

西南典型喀斯特地区石漠化时空演变特征——以贵州省普定县为例

PDF HTML阅读 XML下载 导出引用 引用提醒 西南典型喀斯特地区石漠化时空演变特征——以贵州省普定县为例 DOI: 10.5846/stxb201806011216 作者: 作者单位: 中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所,中国科学院地球化学研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划（2016YFC0502102）；中国科学院科技服务网络计划（KFJ-STS-ZDTP-036）；"西部之光"人才培养计划（A类）（〔2018〕X）；贵州省科技计划（2017-2966） Spatio-temporal characteristics of rocky desertification in typical Karst areas of Southwest China: A case study of Puding County, Guizhou Province Author: Affiliation: Institute of Geochemistry,,State Key Laboratory of environmental geochemistry,,,,,,,,,, Fund Project: National key research program of China (No. 2016YFC0502102 & 2016YFC0502300), 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:为揭示我国西南典型喀斯特地区石漠化时空演变特征，选取贵州省普定县为研究对象，基于Landsat、DEM等影像数据，提取了坡度和4期植被覆盖度、岩石裸露率分布图，并利用地理探测器获得各自的贡献率，反演了1990-2015年4期石漠化空间分布信息，进而讨论了石漠化时空演变特征。结果表明：（1）在1990-2015年间，普定县石漠化演变复杂，经历了由好转到恶化再到好转的阶段，总体趋势在好转，局部恶化，石漠化治理仍需加大力度；（2）中度以上石漠化集中分布在三岔河沿岸附近，轻度以下石漠化则分布较散乱；（3）潜在和轻度石漠化演变方向复杂，潜在石漠化平均变化速率最大（2.75 km2/a），在1997-2006年间更是达到了16.5 km2/a；（4）植被覆盖度与岩石裸露率的变化主要呈负相关，前者的增加主导了石漠化的好转，而后者的增加则控制了石漠化的恶化；（5）石漠化演变存在突变，在三岔河沿岸附近，存在无/潜在石漠化突变为重度以上石漠化的现象；在靠近城乡居民地附近，存在重度以上石漠化突变为无/潜在石漠化的现象；（6）植被覆盖度、岩石裸露率、坡度能较准确反演石漠化，贡献率分别为44%、42%、14%。本文提供的石漠化反演方法快速高效，制作的图件、数据为同行提供了参考，得出的结论为石漠化治理提供了科学支撑。 Abstract:To reveal the spatiotemporal evolution characteristics of rocky desertification in the typical Karst region of Southwest China, we selected Puding County of Guizhou Province as the research subject. Based on Landsat and DEM image data, we extracted the Slope and the four-stage Fractional Vegetation Coverage and the Rock exposedness rate distribution map; then, we used geo-detectors to obtain their respective contribution rates, and retrieved the spatial distribution information for the four stages of rocky desertification in 1990-2015. Finally, we discussed the temporal and spatial evolution of characteristics of rocky desertification. The results showed that:(1) In the period of 1990-2015, the evolution of rocky desertification in Puding County was complex, it ranged from good to deterioration and then back to improvement, but the overall trend was improving with local deterioration, so the control of rocky desertification still needs to be intensified; (2) Moderate rocky desertification was concentrated in the vicinity of the Sancha River, and the light rocky desertification was distributed. (3) The evolution direction of potential and light rocky desertification were complex, the average change rate of potential rocky desertification was a maximum of 2.75 km2/a, reaching 16.5 km2/a in 1997-2006; (4) Fractional Vegetation Coverage was negatively correlated with the change in Rock exposedness. The increased Fractional Vegetation Coverage led to the improvement of rocky desertification, whereas the increased of Rock exposedness controlled the deterioration of rocky desertification;(5)There was a sudden change in the evolution of rocky desertification, and there was no/potential rocky desertification change to severe rocky desertification near the coast of the Sancha River. Near the urban and rural areas, there was a severe rocky desertification change to no/potential rocky desertification; (6) Fractional Vegetation Coverage, Rock exposedness, and Slope can be used to accurately retrieve rocky desertification, and the contribution rate was 44%, 42%, and 14%, respectively. The inversion method of rocky desertification provided in this paper is fast and efficient, the drawings or data are provided for reference, and the conclusions can provide scientific support for the control of rocky desertification. 参考文献 相似文献 引证文献

不同岩性背景下土壤侵蚀与石漠化关联性分析

PDF HTML阅读 XML下载 导出引用 引用提醒 不同岩性背景下土壤侵蚀与石漠化关联性分析 DOI: 10.5846/stxb201807251583 作者: 作者单位: 贵州师范大学、中国科学院地球化学研究所、,中国科学院地球化学研究所、贵州师范大学,贵州师范大学,贵州师范大学 中国科学院地球化学研究所,贵州师范大学 中国科学院地球化学研究所,中国科学院地球化学研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划（2016YFC0502102）；中国科学院科技服务网络计划（KFJ-STS-ZDTP-036）；"西部之光"人才培养计划（A类）（〔2018〕X）；贵州省科技计划（2017-2966） Effect of lithology background on the correlation between soil erosion and rock desertification Author: Affiliation: Guizhou Normal Universiy、nstitute of Geochemistry, Chinese Academy of Sciences,,,,, Fund Project: This research work was supported jointly by national key research program of China (No. 2016YFC0502102 & 2016YFC0502300), 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:喀斯特地区土壤侵蚀与石漠化问题备受关注，为了定量分析不同岩性下土壤侵蚀与石漠化的关联性，为研究区优化生态环境提供决策依据，以贵州省沿河县为例，以Landsat遥感影像、1：5000地形图、岩性和石漠化为基础数据，采用监督分类方法、表面分析和栅格计算，提取出土壤侵蚀的各项指标因子。对不同岩性背景下土壤侵蚀与石漠化关联性分析，结果显示：（1）沿河县石漠化面积为284.44 km2，占全县国土面积的11.52%。已发生石漠化等级以轻度、中度、强度较显著；土壤侵蚀面积为1838.97 km2，占全县总面积的74.48%，已经发生土壤侵蚀等级以轻度、中度、强度侵蚀为主。（2）灰岩与碎屑岩互层和连续性白云中，石漠化与土壤侵蚀发生面积较显著，分别占石漠化与土壤侵蚀面积的57.99%和50.45%。（3）非碳酸盐岩、灰岩夹碎屑岩、灰岩与白云岩混合、灰岩与碎屑岩互层、连续性白云岩和石灰岩上，石漠化等级与土壤侵蚀程度在潜在和轻度呈负相关、轻度和中度石漠化内呈正相关、中度和极重度石漠化内呈负相关，土壤侵蚀等级与石漠化在微度和轻度侵蚀内呈正相关，在轻度和剧烈侵蚀内呈负相关，其中灰岩与白云岩混合和连续性白云岩上，石漠化等级与土壤侵蚀存在单一的负相关。 Abstract:The occurrence of both soil erosion and rocky desertification in karst areas of China have attracted much attention. In order to quantify the correlation between soil erosion and rocky desertification under different lithologies and to establish a basis for optimizing the area's ecosystem, the present study investigated the correlation between soil erosion and rocky desertification in Yanhe County (Guizhou Province, China) using Landsat remote-sensing data, a 1:5000 topographic map, and both lithology and rocky desertification data. Supervised classification, surface analysis, and grid calculation were used to extract a variety of soil erosion indices. (1) Rocky desertification affected 284.44 km2 of Yanhe County, thereby accounting for 11.52% of the county's total land area, and the grade of rocky desertification was mild, moderate, and strong. Meanwhile, soil erosion affected 1838.97 km2, thereby accounting for 74.48% of the county's total land area, and the grade of soil erosion was mostly mild, moderate, and intense. (2) Both rocky desertification and soil erosion were predominant in the interbedded and continuous limestone and clastic rock, with 57.99% and 50.45% of the rocky desertification and soil erosion found in this area, respectively.(3) Non-carbonate rocks, limestone clastic rocks, limestone and dolomite mixtures, limestone and clastic interbeds, continuous dolomite and limestone, rocky desertification grade, and degree of soil erosion were all negatively correlated with mild, positively correlated with Light and moderate rocky desertification, and negatively correlated with moderate and extremely severe rocky desertification. Soil erosion grade was positively correlated with rocky desertification in Potential and Light erosion. There was a negative correlation between Light and severe erosion. Among the limestone and dolomite mixtures and continuous dolomite, rocky desertification grade was negatively correlated with the degree of soil erosion. 参考文献 相似文献 引证文献

Leaf nitrogen and phosphorus stoichiometry of shrubland plants in the rocky desertification area of Southwestern Hunan, China.

In this paper, we took the leaves of shrubland plants in rocky desertification area in Southwestern Hunan as the research object to analyze the nitrogen (N) and phosphorus (P) stoichiometry characteristics for different functional groups and different grades of rocky desertification, i.e., light rocky desertification (LRD), moderate rocky desertification (MRD) and intense rocky desertification (IRD). The results showed that the average contents of N and P were 12.89 and 1.19 g·kg-1, respectively, and N/P was 11.24 in common shrubland plants in the study area, which indicated that the growth of most plants were mainly limited by N. The content of N was declined in order of deciduous shrubs > evergreen shrubs > annual herbs > perennial herbs. The content of P and N/P were higher in deciduous shrubs than in perennial herbs. Significant differences were found among the main families of plants in terms of the contents of N, P and N/P in the study sites. The plants of Gramineae had the lowest contents of N and P, andtheir growth was mostly restricted by N, while Leguminosae had the highest content of N and N/P, and their productivity was majorly controlled by P. The contents of N and P in the leaves were significantly higher in dicotyledon plants and C3 plants than in monocotyledon plants and C4 plants, but the N/P was not significantly diffe-rent between these two plant categories. The nitrogen-fixing plants had higher content of N and N/P than the non-nitrogen-fixing plants, but the P content was not significantly different between these two plant groups. There were significant correlations between contents of N and P, N/P and N in all study plots. No significant correlation was found between N/P and P content in the examined rocky desertification sites, except for that in MRD. There were no significant differences of the contents of N, P and N/P under different grades of rocky desertification.

Evaluation of soil fertility in the succession of karst rocky desertification using principal component analysis

Abstract. Expanding of karst rocky desertification (RD) area in southwestern China is strangling the sustainable development of local agricultural economy. It is important to evaluate the soil fertility at RD regions for the sustainable management of karst lands. The changes in 19 different soil fertility-related variables along a gradient of karst rocky desertification were investigated in five different counties belonging to the central Hunan province in China. We used principal component analysis method to calculate the soil data matrix and obtained a standardized integrate soil fertility (ISF) indicator to reflect RD grades. The results showed that the succession of RD had different impacts on soil fertility indicators. The changing trend of total organic carbon (TOC), total nitrogen (TN), available phosphorus, microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) was potential RD (PRD) &gt; light RD (LRD) &gt; moderate RD (MRD) &gt; intensive RD (IRD), whereas the changing trend of other indicators was not entirely consistent with the succession of RD. The degradation trend of ISF was basically parallel to the aggravation of RD, and the strength of ISF mean values were in the order of PRD &gt; LRD &gt; MRD &gt; IRD. The TOC, MBC, and MBN could be regarded as the key indicators to evaluate the soil fertility.