Red Soil In South China Research Articles

Impacts of long-term chemical nitrogen fertilization on soil quality, crop yield, and greenhouse gas emissions: With insights into post-lime application responses

The improvement in the agricultural production through continuous and heavy nutrient input like nitrogen fertilizer under the upland red soil of south China deteriorates soil quality, and this practice in the future could threaten future food production and cause serious environmental problems in China. This research is initiated with the objectives of evaluating the impacts of long-term chemical nitrogen fertilization on soil quality, crop yield, and greenhouse gas emissions, with insights into post-lime application responses. Compared to sole application of chemical nitrogen fertilization, combined application with lime increased soil indicators (pH by 6.30 %–7.76 %, Ca2+ by 90.06 %–252.77 %, Mg2+ by 184.47 %–358.05 %, available P by 5.05 %–30.04 %, and soil alkali hydrolysable N by 23.49 %–41.55 %. Combined application of chemical nitrogen fertilization with lime (NPCa (0.59), NPKCa (0.61), and NKCa (0.27) significantly improved soil quality index compared to the sole application of chemical nitrogen fertilization (NP (0.31), NPK (0.36), and NK (0.16). Compared to sole application of chemical nitrogen fertilization, combined application with lime increased grain yield by 48.36 %–61.49 %. Structural equation modeling elucidated that combined application of chemical nitrogen fertilization and lime improved wheat grain yield by improving soil quality. Exchangeable Ca2+, exchangeable Mg2+, pH, and exchangeable Al3+ were the most influential factors of wheat grain yield. Overall, the combined application of chemical nitrogen fertilization and lime decreased global warming potential (calculated from N2O and CO2) by 16.92 % emissions compared to the sole application of chemical nitrogen fertilization. Therefore, liming acidic soil in upland red soil of South China is a promising management option for improved soil quality, wheat grain yield, and mitigation of greenhouse gas emissions.

Nitrogen substitution practice improves soil quality of red soil (Ultisols) in South China by affecting soil properties and microbial community composition

Substituting synthetic nitrogen (N) fertilizer with organic amendments is considered an effective practice to improve soil quality. However, information on the effects of N substitution practices on soil quality in the red soil area in South China is still limited. In this study, therefore, four kinds of organic materials, including maize straw, cow manure, biochar and biogas residue, were applied to sweet maize farmland for six consecutive cropping seasons to substitute 20% synthetic N fertilizer in the Pearl River Delta Plain, which is a typical red soil area in South China. We compared the effects of different N substitution practices with conventional fertilization (CK) on the soil physical, chemical and biological properties and the microbial community structure. A minimum dataset method was utilized to calculate the soil quality index (SQI) under different treatments. The results demonstrated that the N substitution practice improved the SQI by 55%−70% compared to the CK in the red soil of South China by improving the soil physicochemical properties and biological characteristics. Meanwhile, the N substitution practice showed positive effects on changing the microbial community structure. Cow manure substitution showed the best effect due to the increased relative abundance of beneficial phyla in the soil microbiota, such as Proteobacteria, Chloroflexi and Ascomycota, and the decreased relative abundance of Basidiomycota. Finally, the structural equation model illustrated that the N substitution practice greatly improved the SQI in red soil by improving the soil bulk density, pH, β-glucosidase activity, urease activity and microbial community composition. Collectively, all four N substitution practices significantly improved soil quality, and cow manure substitution was the most effective way to improve soil microbial community composition and soil quality. This study provides a research basis for improving soil quality in the red soil region in South China and valuable information for the development of clean agricultural production in typical subtropical areas in East Asia.

Effects of Substituting Synthetic Fertilizer with Organic Materials on Soil Organic Carbon Sequestration and Aggregate Size Distribution in Red Soil in South China

Effects of Substituting Synthetic Fertilizer with Organic Materials on Soil Organic Carbon Sequestration and Aggregate Size Distribution in Red Soil in South China

Construction and evaluation of pedotransfer functions for saturated hydraulic conductivity in the granite red soil regions of southern China

Study regionSix typical regions of granite red soil in southern China. Study focusRegional large-scale Ks analysis of granite red soil in South China is still limited to a large number of repetitive and expensive workloads. It is necessary to construct Ks PTFs suitable for the granite red soil region of South China. In this study, six different regions granite red soil in South China were used to validate the prediction of classical PTFs for Ks, the best combination of predictors was screened and PTFs developed based on stepwise regression methods and machine learning algorithms. New hydrologic insights for the region(1) The coefficient of variation for Ks is 69.87% in the granite red soil region of South China, with a large spatial variability. (2) The six typical PTFs of Ks were poor predictors of Ks for soils in southern China, R2 < 0.4. (3) "Clay+Silt+Sand+BD+SOM+NCP" is the best combination of predictors of soil Ks in the granite red soil region of South China, which can be used in different machine learning algorithms. (4) The constructed MLR model “Ks= 1.501 + 0.043 ×NCP-0.995 ×BD+ 0.034 ×SOM-0.013 ×Clay” with KNN, ANN and BRT machine algorithm models have a prediction accuracy R2 greater than 0.8. This study provides different prediction models for soil Ks in the granitic regions of southern China and lays a theoretical basis for hydrological research in the these regions.

Green Manure Amendment Increases Soil Phosphorus Bioavailability and Peanut Absorption of Phosphorus in Red Soil of South China

Peanut (Arachis hypogaea L.) is one of the most important crops produced worldwide. Peanut is the dominant crop in the typical upland red soil areas of China; however, phosphorus bioavailability in red soil is very low, which severely affects peanut production. To improve the phosphorus bioavailability, which substantially promotes the green development of peanut production, a peanut–green manure rotation field experiment was conducted with six treatments (milkvetch; radish; brassica rape; mustard rape; winter fallow and no-tillage), commencing in September 2017 in the red soil area of Jiangxi province, China. The results show that compared with no-tillage (NT) treatments, different green manure returning treatments had significant effects on soil pH, soil phosphorus components and available potassium content. The particulate phosphorus and soil available phosphorus contents in the green manure treatments were significantly higher than those in the winter fallow (WF) treatment. Compared with the WF treatment, the content of particulate phosphorous in brassica rape (BR), radish (R) and milkvetch (MV) treatments was significantly increased by 6.55%, 3.66% and 2.50%, respectively; the available phosphorus content in mustard rape (MR), BR, R and MV was significantly increased by 20.93%, 25.60%, 23.76% and 18.10%, respectively. In addition, the total phosphorus content of peanut shell in the MV and R treatment was significantly higher than that in the WF treatment, increasing by 33.47% and 60.66%, respectively. Compared with the WF treatment, the peanut biomass of MR, BR and R treatments increased significantly by 19.51%, 29.83% and 19.77%, respectively. The total phosphorus accumulation in all green manure treatments was higher than that in the WF treatment, and the MV treatment reached a significant level at 18.83%. Based on these results, the particulate phosphorus (PP) and available phosphorus were significantly affected by different green manure treatments; green manure amendment improves peanut phosphorus uptake. The use of green manure (especially milkvetch and brassica rape) can be recommended to improve phosphorus bioavailability and yield of peanut in red soil areas.

有机肥施用对红壤原生生物与微生物互作的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 有机肥施用对红壤原生生物与微生物互作的影响 DOI: 10.5846/stxb202112253651 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家优秀青年基金（41922048）；国家面上基金（42107336，42177298） Impacts of manure application on interaction between protists community and microorganisms in red soil Author: Affiliation: Fund Project: National Science Fund for Excellent Young Scholars of China (41922048), National Natural Science Foundation of China (42177298, 42107336) 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:为明确不同施肥处理对土壤原生生物群落、微生物碳代谢活性的影响，以南方典型旱地红壤为研究对象，基于中国科学院鹰潭红壤生态实验站玉米单作系统有机培肥长期定位试验，选取不施肥（M0）、低量猪粪（M1）、高量猪粪（M2）、高量猪粪+石灰（M3）4个处理，利用高通量测序技术研究不同猪粪处理下红壤原生生物多样性、群落结构的变化，揭示原生生物与微生物互作对土壤微生物碳代谢活性和玉米产量的影响。结果表明：①长期施用猪粪处理下，土壤pH、有机质（SOM）、全氮（TN）、全磷（TP）、速效磷（AP）和速效钾（AK）的含量显著提高；②与M0处理相比，施肥处理显著提高了原生生物生物量和多样性，并且显著改变了其群落结构，其中土壤TP、pH、AP、TN、SOM和AK是原生生物群落结构变化的重要驱动因子；③施肥处理显著提高了土壤细菌和真菌生物量，增加了微生物碳代谢活性（Average well color development，AWCD）；④土壤pH和AP通过影响原生生物多样性和群落结构，间接提高了微生物碳代谢活性和玉米产量。本研究结果为提升旱地红壤的生物多样性，保障土壤健康和维持生态系统服务功能提供了科学依据。 Abstract:The purpose of this study was to investigate the protist community and soil microbial carbon metabolism with pig manure application in the dryland red soil of south China. The long-term field experiment was conducted in maize mono-cropping system at the National Agro-Ecosystem Observation and Research Station in Yingtan, Jiangxi Province. Four treatments included no manure (M0), low manure (M1), high manure (M2), and high manure with lime addition (M3). The high-throughput sequencing of 18S rRNA gene was used to explore the diversity and structure of soil protist community, and to estimate the effect of protists-microorganisms interaction on microbial carbon metabolism and maize yield. Our results showed that soil chemical properties significantly varied under the four fertilization treatments. Soil pH, soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), and available potassium (AK) were significantly increased under manure treatments. Compared with M0 treatment, manure treatments (M1, M2, and M3) significantly enhanced the biomass and diversity of protist, and remarkably modified the protist community structure. The protist community composition was mainly affected by soil TP, pH, AP, TN, SOM, and AK. Manure application significantly improved the bacterial and fungal biomasses, and consequently promoted microbial carbon metabolism indicated by the values of average well color development (AWCD). Structural equation modelling indicated that soil pH and AP could indirectly increase microbial carbon metabolism and maize yield through regulating the diversity and structure of protist community. Taken together, we provide the scientific basis for promoting the microbial diversity in the dryland red soil, and maintaining soil health and ecosystem service functioning. 参考文献 相似文献 引证文献

Long‐term cultivation of Miscanthus and switchgrass accelerates soil organic carbon accumulation by decreasing carbon mineralization in infertile red soil

AbstractPerennial energy crops (PECs) such as Miscanthus spp. and switchgrass (Panicum virgatum L.) may have particular influence on microbial communities and their functions in soil organic carbon (C) utilization and mineralization (Cm). In this study, long‐term effects of PECs on Cm and soil hydrolase activities were examined in bulk and rhizosphere soils of Miscanthus and switchgrass grown on a red soil in South China. Long‐term cultivation (10 years) of PECs led to increases in soil organic C (SOC) and the absolute Cm of bulk and rhizosphere soils. Total Cm was correlated with dissolved organic C and dissolved organic nitrogen (N) in red soils. The specific Cm in bulk soils of switchgrass and Miscanthus were decreased by 11.73% and 20.67% comparing with the control group, respectively. Cultivation of PECs led to a relatively high C/N ratio. There was a difference in priming effect on activities of β‐glucosidase (BG), leucine amin peptidase, N‐acetyl‐β‐glucosaminidase (NAG), and phosphatase between rhizosphere and bulk soils. Compared with the control without PECs, BG activity did not change significantly in bulk soils of PECs, whereas NAG activity decreased significantly. Soil microorganisms were generally limited by soil C and phosphorus (P) in the red soil. The C and P limitations were significantly linearly related with relative Cm (p &lt; 0.05). Phosphorus limitations in microbial communities were lower with PECs than in the control, indicating that cultivation of PECs could provide an optimal nutrient environment for both plants and microorganisms. Thus, long‐term cultivation of PECs increased SOC content but decreased specific Cm rates. However, because C and P limitations remain for plants and soil microbial communities, optimum fertilization is also necessary for sustainable growth of PECs on red soils.

Resource Recycling of Red Soil to Synthesize Fe2O3/FAU-type Zeolite Composite Material for Heavy Metal Removal.

Heavy metal-polluted water is of great concern to human health and the eco-environment. In situ water remediation techniques enabled by highly efficient adsorption materials are of great importance in these circumstances. Among all the materials used in water remediation, iron-based nanomaterials and porous materials are of great interest, benefiting from their rich redox reactivity and adsorption function. Here, we developed a facile protocol to directly convert the widely spread red soil in south China to fabricate the Fe2O3/faujasite (FAU)-type zeolite composite material. The detailed synthesis procedure and synthesis parameters, such as reaction temperature, reaction time, and the Si/Al ratio in the raw materials, have been carefully tuned. The as-synthesized composite materials show good adsorption capacity for typical heavy metal(loid) ions. With 0.001 g/mL Fe2O3/FAU-type zeolite composite material added to different heavy metal(loid)-polluted aqueous solutions (single type of heavy metal(loid) concentration: 1,000 mg/L [ppm]), the adsorption capacity was shown to be 172, 45, 170, 40, 429, 693, 94, and 133 mg/g for Cu (II), Cr (III), Cr (VI), As (III), Cd (II), Pb (II), Zn (II), and Ni (II) removal, respectively, which can be further expanded for heavy metal-polluted water and soil remediation.

Soil Carbon Sink Effect of Main Management Models in Typical Granite Erosion Area of Red Soil in South China

Soil Carbon Sink Effect of Main Management Models in Typical Granite Erosion Area of Red Soil in South China

Long-term fertilization and intensive cropping enhance carbon and nitrogen accumulated in soil clay-sized particles of red soil in South China

Understanding the underlying mechanism of soil carbon (C) and nitrogen (N) accumulation is of great significance for soil C sequestration and climate change mitigation, as well as soil fertility improvement. The objective of this study was to evaluate the response of C and N accumulation in aggregates and fine soil particles to long-term mineral fertilizer and manure application. Five treatments from a long-term experiment with double maize cropping were examined in this study, i.e., (1) no fertilizer (control); (2) mineral nitrogen, phosphorus, and potassium application (NPK); (3) doubled application rate of the NPK (2NPK); (4) pig manure alone (M); and (5) mineral NPK fertilizers and manure combination (NPKM). By using physical particle-sized fractionation, we analyzed soil organic carbon (OC) and total nitrogen (N), and δ13C of OC in bulk soil and aggregates (53–2000 μm) and, coarse silt-sized fraction (5–53 μm), fine silt-sized fraction (2–5 μm), and clay-sized fraction (< 2 μm) under those five treatments. Fertilizer application for 24 years, particularly M and NPKM treatments, significantly increased the concentration and proportion of OC and total N associated with aggregates and clay-sized fraction as compared with control. Manure application significantly increased the proportion of OC by 6.6–7.8 points in aggregates, whereas it was by 22.6–25.0 points in clay-sized fraction. Clay-sized fraction-associated C and N showed a non-linear response to C and N accumulation in bulk soil, contributing approximately 47% and 69% to soil OC and total N, respectively. Moreover, the mass proportion of aggregates and the mass ratio of aggregates to fine soil particles increased significantly with C accumulation in fine silt-sized and clay-sized fraction. Organic carbon and total nitrogen accumulation in soil clay-sized particles play important role in soil C and N sequestration in red soil. Our results also suggested that C accumulation in fine soil particles might benefit soil aggregation in intensive cropping system of South China.

Transport of uranium(VI) in red soil in South China: influence of initial pH and carbonate concentration.

Uranium-contaminated wastewater associated with uranium (U) mining and processing inevitably releases into soil environment. In order to assess the risk of U wastewater contamination to groundwater through percolation, U adsorption and transport behavior in a typical red soil in South China was investigated through batch adsorption and column experiments, and initial pH and carbonate concentration were considered of the high-sulfate background electrolyte solution. Results demonstrated that U adsorption isotherms followed the Freundlich model. The adsorption of U to red soil significantly decreased with the decrease of the initial pH from 7 to 3 in the absence of carbonate, protonation-deprotonation reactions controlled the adsorption capacity, and lnCs had a linear relationship with the equilibrium pH (pHeq). In the presence of carbonate, the adsorption was much greater than that in the absence of carbonate owing to the pHeq values buffered by carbonate, but the adsorption decreased with the increase of the carbonate concentration from 3.5 to 6.5 mM. Additionally, the breakthrough curves (BTCs) obtained by column experiments showed that large numbers of H+ and CO32- competed with the U species for adsorption sites, which resulted in BTC overshoot (C/C0 > 1). Numerical simulation results indicated that the BTCs at initial pH 4 and 5 could be well simulated by two-site chemical non-equilibrium model (CNEM), whereas the BTCs of varying initial carbonate concentrations were suitable for one-site CNEM. The fractions of equilibrium adsorption sites (f) seemed to correlate with the fractions of positively charged complexes of U species in solution. The values of partition coefficients (kd') were lower than those measured in batch adsorption experiments, but they had the same variation trend. The values of first-order rate coefficient (ω) for all BTCs were low, representing a relatively slow equilibrium between U in the liquid and solid phases. In conclusion, the mobility of U in the red soil increased with the decrease of the initial pH and with the increase of the initial carbonate concentrations.

In-Situ Remediation of Cadmium and Atrazine Contaminated Acid Red Soil of South China Using Sepiolite and Biochar.

The in-situ immobilization effect of sepiolite and biochar on the compound pollution of cadmium (Cd) and atrazine in acid red soil of south China was studied. Results showed that in a certain concentration range, sepiolite and biochar can improve the germination rate, ensure normal growth and increase biomass of pakchoi, reduce the content of Cd in edible parts of pakchoi in different degrees and meet international standards, and restrain absorption of atrazine in pakchoi completely. Sepiolite was more effective than biochar for the immobilization of Cd, while biochar was more effective than sepiolite for the immobilization of atrazine. Combined application of sepiolite and biochar in soil contaminated by Cd and atrazine was better than individual applications of sepiolite or biochar. The remediation method applied in this research can effectively repair the acid red soil with combined pollution of Cd and atrazine in south China, while also providing ideas for in-situ remediation of farmland soil with combined pollution of pesticides and metals.

Mechanisms by which organic fertilizer and effective microbes mitigate peanut continuous cropping yield constraints in a red soil of south China

Red soils are acid soils which occupy about one fifth of the total area of tropical and subtropical soils in China. Peanut (Arachis hypogaea L.) is regarded as the main oil and cash crop in the red soil region. However, yields of peanut have gradually but significantly declined under continuous cropping. We conducted a field experiment in Jiangxi province, south China from 1996 to investigate the mitigation of the peanut continuous cropping constraint. Three types of fertilizer (chemical, organic, and organic fertilizer with effective microbes) were applied in the field. After 20 years of cropping the continuous cropping constraint was found to be more severe where chemical fertilizers were applied and was mitigated where the fields were amended with organic fertilizer or organic fertilizer with effective microbes. Soil properties and the rhizosphere bacterial community structure were determined in 2016. Long-term application (20 years) of organic fertilizer increased the plant available phosphorus in the rhizosphere soil. Phosphorus is known to be one of the most limiting factors for peanut growth in red soils and peanut yield was promoted as the soil phosphorus status increased. Organic fertilizer and effective microbes also optimized the rhizobacteria of peanut to mitigate the continuous cropping obstacle. The bacterial wilt pathogen (Ralstonia) decreased in abundance in the rhizosphere and bacterial wilt disease of peanut declined significantly. Moreover, beneficial bacteria in the rhizosphere capable of promoting peanut growth increased in abundance.

Mechanisms of biochar effects on thermal properties of red soil in south China

Soil thermal properties play crucial roles in governing heat storage and conduction across soil profiles and affect various soil processes by determining soil microclimate. Biochar has gained wide attention as a soil amendment to affect a series of soil physiochemical properties. However, little information is available on the integrated effects of biochar application on soil thermal properties. Disturbed soil columns with consistent bulk density (1.3 g cm−3) were packed using clayey red soil and wheat straw biochar at application rates (w/w) of 0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%. Besides, a 2-year field experiment of biochar application at the same application rates with crop rotation was performed in a red soil region in south China. Soil thermal properties, i.e. thermal capacity, conductivity and diffusivity, were measured with heat pulse method for disturbed soil columns and undisturbed soil cores from the field at controlled soil water contents ranging from 0% to 40% at an interval of 5%. Furthermore, soil thermal properties were measured in situ for different biochar treatments under field conditions. For the disturbed soil columns, no significant effect of biochar application on soil thermal properties was detected at most of the soil water content levels. Additionally, it indicated that biochar application cannot directly affect soil thermal properties by changing soil solid substances composition at application rates up to 2.5% w/w. The results from undisturbed soil cores showed significant decreasing effects of biochar application on soil thermal capacity and diffusivity at most of the soil water content levels. The results from in situ measurement showed significant decreasing effect of biochar application on soil thermal capacity, conductivity and diffusivity. Two main underlying mechanisms were identified for the effects of biochar application on soil thermal properties. One is the negative effect of biochar application on soil thermal capacity and conductivity by increasing the soil total porosity, mainly by increase in the meso- and macro-porosity. The other is the positive effects of biochar application on soil thermal properties by increasing the soil water content through improved soil water retention ability. The negative effects through change in the soil structure were the dominant effect under field condition.

The dynamics of carbon accumulation in Eucalyptus and Acacia plantations in the Pearl River delta region

Plantation type and age strongly influence the quantity of carbon stored in forest ecosystems. The marked increase in total ecosystem carbon stock achieved over time by the Eucalyptus and Acacia plantations has confirmed that the afforestation of degraded soils can contribute positively to carbon sequestration. Reforestation has been widely conducted to restore and protect the eroded red soil in south China in recent decades. The question as to whether the content of soil organic carbon (SOC) can be boosted by establishing plantations of fast-growing tree species remains unresolved. We addressed whether the afforestation of degraded soils can contribute positively to carbon sequestration, and whether the accumulation of SOC is more effective under a nitrogen fixing species such as Acacia than under Eucalyptus. Here, a study was undertaken to measure the quantity of total ecosystem carbon (TEC) accumulated by plantations of both Eucalyptus and Acacia spp. in the Pearl River Delta region of southern China. The quantity of TEC increased significantly with stand age in both plantation types (P < 0.05). The largest single component of TEC was SOC, with stand age having a considerable effect on both SOC and overall biomass. The accumulation of SOC in the top 100 cm of the soil profile was higher under Acacia than under Eucalyptus (P < 0.05). In terms of carbon sequestration, the afforestation of Eucalyptus and Acacia represent an effective forest management practice. The accumulation of SOC is more effective under Acacia than under Eucalyptus.

Alteration of soil bacterial interaction networks driven by different long-term fertilization management practices in the red soil of South China

Interactions among soil bacteria occur widely and play important roles in the maintenance of soil functions. Long-term fertilization management practices have distinct effects on soil fertility and the soil microbial activity and community, which are closely associated with soil microbial interactions. Red soil is typically low-productivity soil in South China. Chemical nitrogen fertilization caused serious soil acidification and low-productivity (defined as the acidified soil group, Ac), whereas the application of lime to the acidified soil increased the soil pH (defined as the quicklime improvement soil group, Qlime). Long-term manure or fallow treatment maintained the soil pH and increased the soil fertility (defined as the high-productivity potential soil group, HPP). A molecular ecological network analysis method was used to analyze 454 pyrosequencing data of bacterial communities from the HPP, Ac and Qlime soils. Several major differences were observed among the three constructed networks. First, the HPP network contained the largest ratio of positive to negative correlations, whereas the Ac network contained the smallest. Second, the HPP and Ac networks shared only 8.67% of their operational taxonomic units (OTUs), whereas Ac and Qlime shared 27.04%. Third, the HPP network contained the most “module hubs” (A set of OTUs that have strong interactions or common functions are grouped as a “module” in network analysis. These OTUs are called “nodes”. And the nodes with high connectivity to many other nodes within the same module are “module hubs”.), whereas Ac contained the fewest. These results demonstrated that the bacterial community of HPP was a better organized or a better operated community than Ac and that quicklime application helped to order the bacterial community. By comparing the topological roles of nodes in different networks, we proposed that there should be more module hubs in the networks of higher-productivity soils and hypothesized that these OTUs could be indicators of high-productivity.

亚热带典型红壤侵蚀区人类活动对植被覆盖度及景观格局的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 亚热带典型红壤侵蚀区人类活动对植被覆盖度及景观格局的影响 DOI: 10.5846/stxb201504220831 作者: 作者单位: 福建师范大学,福建师范大学,福建师范大学,福建师范大学,福建师范大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家“973”前期研究课题（2012CB722203）；国家自然科学基金项目（31130013，31370465，31200366） Spatial and temporal variations in vegetation cover in an eroded region of substropical red soil and its relationship with the impact of human activity Author: Affiliation: Fujian Normal University,Fujian Normal University,Fujian Normal University,Fujian Normal University,Fujian Normal University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:福建省长汀县是中国南方最严重的水土流失区之一，在20世纪80年代初和2000年两次集中治理的推动下，当地生态环境已得到显著改善。基于Landsat系列卫星影像提取长汀县1975-2013年共6期植被覆盖度分布图，分析该区在不同时期植被覆盖度及其空间格局的时空动态，并探讨人类干扰与政策治理对植被覆盖度及景观格局的影响。结果表明：（1）近38年来，长汀县平均植被覆盖度由47.02%（1975）提升至71.47%（2013），在覆盖度结构上逐渐形成以中高和高植被覆盖度占主导的格局；县域中部河田盆地的植被覆盖度由30.83%（1975）提升至60.34%（2013）。（2）在景观格局上，研究期间长汀县极低、低和中低覆盖度斑块平均面积呈波动下降趋势、同时斑块密度增加，而中高、高植被覆盖度区域面积扩大，表明封禁、造林等治理措施导致植被覆盖度较高的区域不断汇聚成片。（3）植被覆盖度的提升在空间上主要集中在海拔600 m和坡度25°以下区域，尤其在海拔400-600 m和坡度5°-15°区域最显著，表明植被的破坏和恢复过程与人类活动的联系密切。（4）空间分析表明，在距离农户居民地边缘1.2 km的范围内，越接近居民地中心的区域植被覆盖度越低、破碎度越大且恢复缓慢，但这种空间差异伴随治理进行正在逐步减弱。总体上看，长汀县生态治理和人类干扰的长期驱动影响，其恢复速度在不断提升。 Abstract:In China, the area of red soil in South China in second only to the loess plateau in terms of area of soil erosion. Changting County in Fujian Province suffers the most serious water and soil erosion where its forest vegetation has been seriously damaged. Intensive large-scale measures to control erosion have been conducted twice in this area during the early 1980s and 2000s. Driven by both of the control measures and social and economic policies, the ecological environment there has been improved significantly and Changting has become a typical example of soil erosion control in China. Based on Landsat satellite images, this study extracted 6 vegetation fraction distribution maps from 1975 to 2013, and analyzed the variation in vegetation cover and landscape pattern during three major periods: 1975-1989, 1989-2000, and 2000-2013. The different terrain characteristics (such as height and slope) and distances from residential areas were also extracted. The results showed the following. (1) The average vegetation coverage of Changting County increased from 47.02% in 1975 to 71.47% in 2013, and the structure of vegetation coverage has been transformed into one dominated by medium-high and high coverage. In the middle of the county, vegetation coverage in the Hetian basin and its vicinity rose from 30.83% in 1975 to 60.34% in 2013. Widely and contiguously distributed forests with low cover in the basin have been replaced by a higher coverage of coniferous forest patches. With the implementation of soil erosion control measures, the vegetation cover of the Hetian basin increased by 8.47% and 13.81%, respectively, during the two intensive control period from 1975 to 1989 and 2000 to 2013. (2) With regards to the landscape pattern of the vegetation cover, the average patch areas of the low, and moderately low level vegetation cover in Changting County showed a trend of falling variability, and patch density increased. In contrast, the area with moderately high and high cover has shown greater volatility. The result showed that ecological intervention leads to the original good vegetation coverage area become more focus, and the poor coverage area distribution gradually broken at the same time. (3) The increase in vegetation coverage has occurred mainly in an area with an elevation lower than 600 m or slope less than 25°, particularly in the area at an altitude ranging from 400 m to 600 m or with a slope ranging from 5°to 15°. It is worth noting that, during 2000-2013, the vegetation coverage increased by more than 10% in the area below 600 m elevation and slope from 5°to 25°, which demonstrates the destruction and restoration of forest vegetation are affected by terrain, and closely related to effects of human activity. (4) Distance to villages reflects the intensity of the impact of human activity on vegetation destruction and restoration. In the area within 50 m from villages, vegetation coverage is the lowest, and it recovers slowest during the periods when the soil erosion control policy was implemented. With increasing distance to villages, the vegetation fraction increased both in value and percentage with time, although this tendency decreases to a stable state in areas more than 1.2 km from village edges. Moreover, human activities also led to increasing fragmentation of the vegetation landscape around residential areas; however, this phenomenon becomes gradually weaker with ecological management under the guidance of the government. Consequently, the vegetation coverage and landscape pattern changes with ecological management and the long-term effects of human activity in this area, with an increasing recovery speed. 参考文献 相似文献 引证文献

Effects of simulated acid rain on microbial characteristics in a lateritic red soil.

A laboratory experiment was performed to examine the impact of simulated acid rain (SAR) on nutrient leaching, microbial biomass, and microbial activities in a lateritic red soil in South China. The soil column leaching experiment was conducted over a 60-day period with the following six SAR pH treatments (levels): 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 and one control treatment (pH = 7). Compared with the control treatment, the concentrations of soil organic matter, total nitrogen, total phosphorus, total potassium, soil microbial biomass carbon (MBC), soil microbial biomass nitrogen (MBN), and average well color density (AWCD) in the Ecoplates were all significantly decreased by leaching with SAR at different pH levels. The decrease in MBC and MBN indicated that acid rain reduced the soil microbial population, while the decrease in AWCD revealed that acid rain had a negative effect on soil bacterial metabolic function. Soil basal respiration increased gradually from pH 4.0 to 7.0 but decreased dramatically from pH 2.5 to 3.0. The decrease in soil nutrient was the major reason for the change of soil microbial functions. A principal component analysis showed that the major carbon sources used by the bacteria were carbohydrates and carboxylic acids.

Effects of atmospheric deposition nitrogen flux and its composition on soil solution chemistry from a red soil farmland, southeast China.

A detailed study on the solution chemistry of red soil in South China is presented. Data are collected from two simulated column-leaching experiments with an improved setup to evaluate the effects of atmospheric N deposition (ADN) composition and ADN flux on agricultural soil acidification using a (15)N tracer technique and an in situ soil solution sampler. The results show that solution pH values decline regardless of the increase of the NH4(+)/NO3(-) ratio in the ADN composition or ADN flux, while exchangeable Al(3+), Ca(2+), Mg(2+), and K(+) concentrations increase at different soil depths (20, 40, and 60 cm). Compared with the control, ADN (60 kg per ha per year N, NH4(+)/NO3(-) ratio of 2 : 1) decreases solution pH values, increases solution concentrations of NO3(-)-N, Al(3+), Ca(2+) and Mg(2+) at the middle and lower soil depths, and promotes their removal. NH4(+)-N was not detected in red soil solutions of all the three soil layers, which might be attributed to effects of nitrification, absorption and fixation in farmland red soil. Some of the NO3(-)-N concentrations at 40-60 cm soil depth exceed the safe drinking level of 10 mg L(-1), especially when the ADN flux is beyond 60 kg ha(-1) N. These features are critical for understanding the ADN agro-ecological effects, and for future assessment of ecological critical loads of ADN in red soil farmlands.

Quantification of Anthropogenic Acidification Under Long-term Fertilization in the Upland Red Soil of South China

Soil acidification in croplands is largely affected by various fertilization practices in long-term scales. However, the differences from the sources and sinks of proton in agroecosystems between long-term fertilization practices are poorly understood. Based on the role of the carbon and nitrogen cycle in soil acidification, experimental data from 1991 to 2006 involving wheat (Triticum aestivum) and maize (Zea mays) rotation in the upland red soil of south China was used to advance the methodology for quantifying soil acidification in croplands. One no-fertilizer control and seven fertilization treatments with 300 kg ha−1 year−1 nitrogen were analyzed in the study. Soil net acid addition rates (NAAR) in the long-term scale were significantly and positively correlated (P < 0.01, n = 8), with rates of decline in topsoil pH varying from 0.006 to 0.122 units year−1. Total proton sources with similar values (17.73–19.53 Kmol ha−1 year−1) and the negative and linear correlation between the effects of nitrogen cycle (HNCE) and carbon cycle (HCCE) were found under all fertilization treatments. Characterized as the distribution of a larger percentage in HCCE than in HNCE, mineral fertilizer amendments with manure at the appropriate nitrogen rate should be regarded as the optimal nutrient-management strategy for sustainable agriculture in the upland red soil.