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| 1 | Evaluation of soil fertility of the shelter-forest land along the Tarim Desert Highway显示文摘To study the changes of soil fertility of the shelter-forest land along the Tarim Desert Highway, soils from the forest land were collected at the layers of 0―10 cm, 10―20 cm, 20―30 cm. Different soil fertility parameters were measured, and quantitative evaluation of soil fertility was performed by the soil integrated fertility index (IFI). The main results show that the construction of the shelter forest along the Tarim Desert Highway improved the soil physical structure, increased soil porosity and enhanced wa- ter-holding capacity. With the increase of plantation time of the shelter forest, soil microbial biomass C, N, P and the activities of six types of enzyme were enhanced, which promoted the accumulation and transformation of soil nutrients of the forest land. Consequently, the soil nutrients in 12-year-old forest land were much higher than in the newer ones and drifting sand. However, soil salt content of the older forest land was higher owing to the drip-irrigation with salt water. Through the comprehensive evalua- tion, we found that soil fertility index in the forest land was enhanced with the forest age, and it had close correlations with the growth indices of the forest trees. In summary, construction of the shelterforest along the Tarim Desert Highway accelerated the improvement of aeolian soil in the forest land, and the soil fertility improved year by year. We conclude that the forest trees grow normally under the stress of the present drip-irrigation with salt water. | JIN ZhengZhong LEI JiaQiang XU XinWen LI ShengYu ZHAO SiFeng QIU YongZhi XU Bo | 2008 | Chinese Science Bulletin2008，53，S2： | 18 |
| 2 | 黄土高原丘陵沟壑区新造耕地质量评价(英文)显示文摘In order to better understand the quality of newly created farmland(NF) as well as slope and check-dam farmland(CF) soil quality, two typical traditional farmland areas within the hilly and gully region of Chinese Loess Plateau were selected as controls in this analysis.The results of this study initially reveal that pH values for slope farmland(SF) and CF were significantly lower(P < 0.05) than those for NF and that SF values were always greater than those of their CF counterparts. At the same time, cation exchange capacity(CEC) and soil organic matter(SOM) occurred in the following size-decreasing sequence, i.e., CF, SF, and NF. Data also show that long-term planting has resulted in increases in total nitrogen(N),available N, total phosphorus(P), available P, total potassium(K) and available K and has also enhanced concentrations of soil copper(Cu), zinc(Zn), iron(Fe), and manganese(Mg)as well as soil cadmium(Ca), lead(Pb), chromium(Cr), and mercury(Hg). These latter elements occur in the concentration sequence of SF > CF > NF. Overall, results indicate that long-term planting negatively impacts soil health because of the accumulation of toxic heavy metals. This means that farmland planted over longer timescales needs to lie fallow to enable it to rehabilitate while NF requires the addition of organic matter as well as rotational utilization in order to facilitate the development of green agriculture. | 陈怡平 毋俊华 王洪 马吉福 苏翠翠 王凯博 王益 | 2019 | Journal of Geographical Sciences2019，0，5： | 9 |
| 3 | Organic amendments increase corn yield by enhancing soil resilience to climate change显示文摘A 22-year field experiment was conducted in Gongzhuling, Jilin province, China to investigate corn yield response to fertilization practice. Compared to an unfertilized control(CK), all fertilization treatments, including inorganic nitrogen fertilizer only(N), balanced inorganic fertilizers(NPK), NPK plus corn straw(SNPK), and NPK plus farmyard manure(MNPK), resulted in significant increases in corn yield. However, only organic matter amendments sustained increasing yield trends, with annual rates of 0.137 and 0.194 t ha-1for the SPNK and MNPK treatments, respectively(P < 0.05). During the 22 years, the daily mean, maximum and minimum temperatures increased by 0.50, 0.53, and 0.46 °C per decade, whereas precipitation displayed no significant change but showed large seasonal variation. According to a regression analysis, increased air temperature exerted positive effects on corn yields under the SNPK and the MNPK treatments. Under both treatments,soil organic carbon contents and soil nutrient availabilities increased significantly compared to their initial levels in 1990, whereas soil bulk density and total porosity changed slightly under the two treatments, which showed higher soil water storage than other treatments. In contrast, significant increases in soil bulk density and decreases in soil total porosity and soil nutrient availability were observed under the CK, N and NPK treatments. The contributions of soil fertility to corn yield were 28.4%, 37.9%, 38.4%, 39.0%,and 42.9% under CK, N, NPK, SNPK, and MNPK treatments, respectively, whereas climate changes accounted for 27.0%, 14.6%, 12.4%, 11.8%, and 10.8%. These results indicate that, in Northeast China, organic matter amendments can mitigate negative and exploit positive effects of climate change on crop production by enhancing soil quality. | Zhenwei Song Hongjun Gao Ping Zhu Chang Peng Aixing Deng Chengyan Zheng Md Abdul Mannaf Md Nurul Islam Weijian Zhang | 2015 | The Crop Journal2015，3，2： | 8 |
| 4 | A new procedure combining GC-MS with accelerated solvent extraction for the analysis of phthalic acid esters in contaminated soils显示文摘An optimized procedure based on gas chromatography-mass spectrometry (GC-MS) combined with accelerated solvent extraction (ASE) is developed for the analysis of six phthalic acid esters (PAEs), which are priority soil pollutants nominated by United States Environmental Protection Agency (USEPA). Quantification of PAEs in soil employs ultrasonic extraction (UE) (USEPA 3550) and ASE (USEPA 3545), followed by clean up procedures involving three different chromatography columns and two combined elution methods. GC-MS conditions under selected ion monitoring (SIM) mode are described and quality assurance and quality control (QA/ QC) criteria with high accuracy and sensitivity for target analytes were achieved. Method reliability is assured with the use of an isotopically labeled PAE, di-n-butyl phthalate-d4 (DnBP-D4), as a surrogate, and benzyl benzoate (BB) as an internal standard, and with the analysis of certified reference materials (CRM). QA/QC for the developed procedure was tested in four PAE-spiked soils and one PAE-contaminated soil. The four spiked soils were originated from typical Chinese agricultural fields and the contaminated soil was obtained from an electronic waste dismantling area. Instrument detection limits (IDLs) for the six PAEs ranged 0.10-0.31 μg·L-1 and method detection limits (MDLs) of the four spiked soils varied from a range of 20-70 μg· kg -1 to a range of 90-290 μg· kg-1. Lineal-iVy of response between 20 μg· L-1 and 2mg.L~ was also established and the correlation coefficients (R) were a11〉0.998. Spiked soil matrix showed relative recovery rates between 75 and 120% for the six target compounds and about 93% for the surrogate substance. The developed procedure is anticipated to be highly applicable for field surveys of soil PAE pollution in China. | Tingting MA Ying TENG Peter CHRISTIE Yongming LUO Yongshan CHEN Mao YE | 2013 | Frontiers of Environmental Science & Engineering2013，7，1： | 8 |
| 5 | Soil quality assessment across different stands in tropical moist deciduous forests of Nagaland,India显示文摘To analyze the relationship between the management of three forest stand plantations and soil quality in the Dimapur district of the Northeastern Himalayan region,India,three forest soil profiles,covered by different species stands,at three depths were tested for 13 physical and chemical variables.Only four of these variables(electric conductivity,bulk density exchangeable Mg and available P)were included in a minimum data set,after using a varimax rotation algorithm in a principal component analysis,and subsequently used to calculate a soil quality index(SQI).Results showed higher SQIs in the surface layers(0–20 cm depth)than in the deeper ones.Average weighed SQI varied significantly(P<0.05)through the three considered forest sites,with the lowest value at site FS3.These findings reveal that the approach used here is suitable for preliminary screening of the impact of a forestry species on soil,to aid in species selection and improve soil health for afforestation and reforestation projects. | Gaurav Mishra Rossana Marzaioli Krishna Giri Shailesh Pandey | 2019 | Journal of Forestry Research2019，30，4： | 5 |
| 6 | Sources and Ecological Risks of Heavy Metals in Soils Under Different Land Uses in Bangladesh显示文摘Soil heavy metal pollution, influenced by both natural and anthropogenic factors, significantly reduces environmental quality. In this study, Cr, Ni, Cu, As, Cd, and Pb in eight different land-use soils from Patuakhali District in Bangladesh were assessed. Concentrations of Cr, Ni, Cu, As, Cd, and Pb in soils were 1-87, 5-271, 4-181, 0-80, 0.2-24.0, and 5-276 mg kg-1, respectively, measured using an inductively coupled plasma-mass spectrometer. The enrichment factor, pollution load index (PLI), and contamination factor (CJ) of metal i were used to assess the ecological risk posed by metals in soils. The PLI ranged from 0.78 to 2.66, indicating baseline levels to progressive deterioration of soil due to metal contamination. However, C;of Cd ranged from 1.8 to 12.0, which showed that the studied soils were strongly impacted by Cd. Considering the severity of the potential ecological risk of a single metal, the descending order was Cd > As > Pb > Cu > Ni > Cr. Soils under all land uses showed moderate to very high potential ecological risk. | Mohammad Saiful ISLAM Mohammad Kawser AHMED Mohammad Habibullah AL-MAMUN Shah Mohammad Asraful ISLAM | 2019 | Pedosphere2019，29，5： | 5 |
| 7 | Quality Control and Evaluation of the Observed Daily Data in the North American Soil Moisture Database显示文摘The North American Soil Moisture Database (NASMD) was initiated in 2011 to assemble and homogenize in situ soil moisture measurements from 32 observational networks in the United States and Canada encompassing more than 1800 stations. Although statistical quality control (QC) procedures have been applied in the NASMD, the soil moisture content tends to be systematically underestimated by in situ sensors in frozen soils, and using a single maximum threshold (i.e., 0.6 m3 m-3) may not be sufficient for robust QC because of the diverse soil textures in North America. In this study, based on the in situ soil porosity and North American Land Data Assimilation System phase 2 (NLDAS-2) Noah soil temperature, the simple automated QC method is revised to supplement the existing QC approach. This revised QC method is first validated based on the assessment at 78 of the Soil Climate Analysis Network (SCAN) stations where the manually checked data are available, and is then applied to all stations in the NASMD to produce a more strict quality-controlled dataset. The results show that the revised automated QC procedure can flag the spurious and erroneous soil moisture measurements for the SCAN stations, especially for those located in high altitudes and latitudes. Relative to station measurements in the original NASMD, the quality-controlled data show a slightly better agreement with the manually checked soil moisture content. It should be noted that this quality-controlled dataset may be over-flagged for some valid soil moisture measurements due to potential errors of the soil temperature and soil porosity data, and validation in this study is limited by the availability of benchmark soil moisture data. The updated QC and additional validation will be desirable to boost confidence in the product when high-quality data become available in the future. | Weilin LIAO Dagang WANG Guiling WANG Youlong XIA Xiaoping LIU | 2019 | Journal of Meteorological Research2019，33，3： | 4 |
| 8 | Natural Colonization of Rice by Arbuscular Mycorrhizal Fungi in Different Production Areas显示文摘Interactions between plants and soil microorganisms can influence the other interactions in which plants participate, including interactions with herbivores. Many fungi, including arbuscular mycorrhizal fungi(AMF), form symbiotic relationships with the roots they inhabit, and potentially alter defense against pests. The objective of this study was to document the extent of root colonization by AMF on non-flooded rice plants grown under conditions typical of commercial fields. We hypothesized that AMF naturally colonized rice plants in different rice producing field locations. Rice plant samples were collected from areas across the southern United States, including Texas, Mississippi, Arkansas and two research stations in Louisiana. We quantified the amount of AMF colonization in insecticide-free rice plants over three consecutive years(2014–2016). The results revealed natural colonization of AMF in all rice producing areas. In all the three years of survey, rice-AMF associations were the greatest in Arkansas followed by Mississippi and Texas. This research will help draw attention to natural colonization of AMF in rice producing areas that can impact future rice research and production by facilitating agricultural exploitation of the symbiosis. | Lina BERNAOLA Grace CANGE Michael O.WAY Jeffrey GORE Jarrod HARDKE Michael STOUT | 2018 | Rice science2018，25，3： | 4 |
| 9 | Soil Erodibility and Physicochemical Properties of Collapsing Gully Alluvial Fans in Southern China显示文摘In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland,leading to reduced nutrients, increased erodibility, and even desertification. The aim of this study was to investigate soil erodibility(the factor K in the Universal Soil Loss Equation, USLE) and physicochemical properties of the alluvial fans of the most severe collapsing gully erosion areas(Hubei, Jiangxi, Fujian, and Guangdong provinces) in southern China. The soils of the collapsing gully alluvial fans had a higher bulk density, but a lower total porosity, saturated water content, and silt and clay fractions than the control(CK) soils from the farmland without desertification. Soil quality gradually decreased from fan edge to fanhead. Significant decreases were found in soil p H, organic matter, cation exchange capacity, and total potassium, nitrogen, and phosphorus, as well as available nitrogen, phosphorus, and potassium, resulting in a gradual decrease in soil nutrients from the fanedge to the fanhead. Soil erodibility was greatest in the fanhead, and soil erodibility K values of the alluvial fans were 53.71%, 66.28%, 67.53%, and 71.68% greater than that in those of the CK soils of Hubei, Jiangxi, Fujian, and Guangdong, respectively, indicating a significant correlation between the soil erodibility K values and physicochemical properties, particularly sand fraction and organic matter content. The results provide new insights into the relationship between soil physicochemical properties and erodibility of alluvial fans, and suggest that improving soil structure might increase soil fertility in the collapsing gully alluvial fan farmland. | DENG Yusong SHEN Xue XIA Dong CAI Chongfa DING Shuwen WANG Tianwei | 2019 | Pedosphere2019，29，1： | 3 |
| 10 | 基于Geo-SOM方法的土壤环境调查数据库探索性分析(英文)显示文摘A model integrating geo-information and self-organizing map(SOM) for exploring the database of soil environmental surveys was established. The dataset of 5 heavy metals(As, Cd, Cr, Hg, and Pb) was built by the regular grid sampling in Hechi, Guangxi Zhuang Autonomous Region in southern China. Auxiliary datasets were collected throughout the study area to help interpret the potential causes of pollution. The main findings are as follows:(1) Soil samples of 5 elements exhibited strong variation and high skewness. High pollution risk existed in the case study area, especially Hg and Cd.(2) As and Pb had a similar topological distribution pattern, meaning they behaved similarly in the soil environment. Cr had behaviours in soil different from those of the other 4 elements.(3) From the U-matrix of SOM networks, 3 levels of SEQ were identified, and 11 high risk areas of soil heavy metal-contaminated were found throughout the study area, which were basically near rivers,factories, and ore zones.(4) The variations of contamination index(CI) followed the trend of construction land(1.353)> forestland(1.267)> cropland(1.175)> grassland(1.056), which suggest that decision makers should focus more on the problem of soil pollution surrounding industrial and mining enterprises and farmland. | 廖晓勇 陶欢 龚雪刚 李尤 | 2019 | Journal of Geographical Sciences2019，29，10： | 3 |
| 11 | A soil quality index for evaluation of degradation under land use and soil erosion categories in a small mountainous catchment, Iran显示文摘Soil erosion and land use type have long been viewed as being particularly important drivers of soil degradation.The objectives of this study,therefore,were to select a new soil quality index(SQI)which varies significantly with land use/soil erosion,and to evaluate the new SQI using expert opinion.In total,18 soil physical,chemical,and biochemical properties(indicators)were measured on 56 soil samples collected from four land use/soil erosion categories(rangeland/surface erosion,rangeland/subsurface erosion,cultivated land/surface erosion and dry-farming land/surface erosion).Principal component and classification analysis(PCCA)identified five PCs that explained 77.7%of the variation in soil properties with the biochemical PC varying significantly with land use/soil erosion.General discriminant analysis(GDA)selected urease and clay as the most sensitive properties distinguishing the land use/soil erosion categories.The GDA canonical scores for the new SQI were significantly correlated with expert opinion soil surface summed scores(for soil movement,surface litter,pedestalling,rills and flow pattern)derived using the U.S.Department of the Interior Bureau of Land Management(BLM)method.A forward stepwise general regression model revealed that the new SQI values were explained by soil movement,surface litter,and the summed values of the soil surface factors.Overall,this study confirmed that soil quality in the study area in Iran is controlled by land use and corresponding soil erosion. | Kazem NOSRATI Adrian LCOLLINS | 2019 | Journal of Mountain Science2019，16，11： | 2 |
| 12 | A Catastrophe Model to Assess Soil Restoration Under Ecological Restoration in the Red Soil Hilly Region of China显示文摘Current methods that utilize simple data or models to evaluate soil restoration under ecological restoration are not sufficiently rigorous.Soil restoration under ecological restoration measures was evaluated in the red soil hilly region of China by applying the catastrophe model.Among 89 soil sites selected,26(29.21%) were in the middle lobe,10(11.24%) in the upper lobe,and 53(70.79%)in the lower lobe of the process surface in the Cusp catastrophe model.The catastrophic direction of the 26 unstable soil sites was to the upper lobe of the process surface according to vegetation cover change and fieldwork.There was a significant negative correlation of the variation in bifurcation set(? value) with vegetation cover increase,and a higher vegetation cover increase was related to higher unstable probability.The four ecological restoration measures were listed in the order:low-quality forest improvement(LQFI)>arbor-bush-herb mixed plantation(ABHMP)>orchard improvement(OI)>closing measures(CM) according to the proportions of unstable soil sites,which were all higher than no restoration measure,while they were in the order:LQFI | CHEN Zhiqiang CHEN Zhibiao BAI Liyue ZENG Yuee | 2017 | Pedosphere2017，27，4： | 2 |
| 13 | Long-Term Effects of Different Passages of Vehicular Traffic on Soil Properties and Carbon Storage of a Crosby Silt Loam in USA显示文摘The passage of vehicles with heavy axle loads causes soil compaction, and this adversely affects soil properties and crop yield.The adverse effects can persist for several years due to significant changes in key soil properties. However, the mechanisms of the aforementioned effects are not well understood for conservation agriculture(CA)(e.g., no-till(NT)) wherein the use of heavy machinery is considerably common. Therefore, known compaction forces(0 Mg load for compaction(NT-0, control), two passages of 2.5 Mg water wagon axle load(NT-2), and four passages of 2.5 Mg water wagon axle load(NT-4)) were applied to all the plots annually for 20 consecutive years. The experiment was established in 1997 at the Waterman Agricultural and Natural Resources Laboratory(WANRL), Ohio State University, Columbus, Ohio. Each treatment was replicated thrice. Soil samples were obtained in November2016 to determine the effects of variations in the axle load and vehicular passages on carbon(C) and nitrogen(N) storage and selected soil properties of a Crosby silt loam soil under NT-based corn-soybean rotation with residue retention in Central Ohio, USA. Three locations were also randomly selected in an adjoining natural woodlot(WL) soil plot and sampled(30 m away from the compaction field) to compare the effects of vehicular traffic on soil under NT with WL soil. Results revealed that soil bulk density(ρb) and total porosity at 0–10 and 10–20 cm depths were not affected by the passages of vehicular traffic for 20 years under the NT system.The penetration resistance(PR)(1.86 and 2.03 MPa at 0–10 and 10–20 cm soil depths, respectively) was significantly higher under NT-4 compared with that under other treatments. Saturated hydraulic conductivity at 0–10 and 10–20 cm soil depths ranged from19.7 to 31.4 and 18.5 to 29.5 mm d^(-1), respectively, across all the treatments. The proportion of macroaggregates(> 0.25 mm) and microaggregates(< 0.25 mm), mean weight diameter and geometric mean diameter of aggregates, pH, electrical conductivity, and C and N contents and storage did not differ significantly between the treatments at either of the sampling soil depths. The data indicated that 2 to 4 passages of vehicles with 2.5 Mg of axle load did not cause significant compaction of the Crosby silt loam under NT compared with that under natural WL. Therefore, the continuous cultivation of row crops with NT and residue retention is feasible with passages of vehicular traffic for well-drained soils in Central Ohio. | Gulab Singh YADAV Rattan LAL Ram Swaroop MEENA Basant RIMAL | 2019 | Pedosphere2019，29，2： | 1 |
| 14 | Assessment of Seasonal and Site-Specific Variations in Soil Physical,Chemical and Biological Properties Around Opencast Coal Mines显示文摘Coal mining adversely affects soil quality around opencast mines. Therefore, a study was conducted in 2010 and 2011 to assess seasonal and site-specific variations in physical, chemical, and biological properties of soil collected at different distances from mining areas in the Jharia coalfield, India. Throughout the year, the soil in sites near coal mines had a significantly higher bulk density, temperature, elec trical conductivity, and sulfate and heavy metal contents and a significantly lower water-holding capacity, porosity, moisture content, pH, and total nitrogen and available phosphorus contents, compared with the soil collected far from the mines. However, biological properties were site-specific and seasonal. Soil microbial biomass carbon (MBC) and nitrogen (MBN), MBC/MBN, and soil respiration were the highest during the rainy season and the lowest in summer, with the minimum values in the soil near coal mines. A soil quality index revealed a significant effect of heavy metal content on soil biological properties in the coal mining areas. | Bhanu PANDEY Arideep MUKHERJEE Madhoolika AGRAWAL Siddharth SINGH | 2019 | Pedosphere2019，29，5： | 1 |
| 15 | Effects of Mouse Thatched on Soil Temperature, Yield and Quality in Apple Orchard显示文摘[Objectives]This study was conducted to study the effect of mouse thatched on soil temperature,yield and quality in orchards.[Methods]The response of orchard soil,yield and quality to sod culture was studied by comparisons of grassing for two years,three years and clean cultivation.[Results]In April,the soil temperature in mouse thatched area was higher than that in clean cultivation area,and the temperature in the three years of sward was the highest.From May to July,the temperature in mouse thatched area was lower than that in clean cultivation area,and the temperature was lowest in the three years of sward.At the same time,the fruit yield and quality were improved.Averaged the two years,the yield of apple increased by 12%,and the contents of sugar,soluble solids and vitamin C and the firmness of the fruit were increased,and the total acid content was decreased by planting mouse thatched.[Conclusions]Adjusting soil temperature in orchards by planting grass achieved the effects of promoting the activity of microorganisms,facilitating the growth of root system,increasing the yield and improving the quality. | Yanhong LI Na LI Peiping ZHANG Qiangsheng SUN Yao SUN Hongzhang WANG | 2019 | Agricultural Biotechnology2019，8，3： | 1 |
| 16 | Effects of Nano-carbon Humic Acid Water-retaining Fertilizer on Citrus Growth and the Soil Bacterial Community in Citrus Field显示文摘[Objective] In order to reveal the effects of reducing the amount of novel nano-carbon humic acid water-retaining fertilizer(CSF) on soil microbial community structure and citrus growth. [Method]In this study,conventional fertilization was as the control(KC1) in Wanzhou citrus orchard of Three Gorges Reservoir area. CSF reductions by 0%(KC2),10%(KC3),20%(KC4),30%(KC5) and 40%(KC6) were used to analyze the changes of soil bacterial community structure,citrus yield and quality. [Result]The results showed that the observed species,Shannon index,Chao1 index and PD_whole_tree of KC6 were higher than those of KC1,and were the same as KC2. The abundance of Xanthomonadaceae was the highest in KC5. Compared with KC1,the Xanthomonadaceae in KC3,KC4 and KC6 was significantly decreased,and the levels of Nitrosomonadaceae and Pseudomonasaceae were higher than that of KC1 after the treatment of KC6. Sphingomonas in different reduction treatments was lower than that of KC1,but Burkholderia and Pseudomonas were significantly higher than those of KC1. It was found that the similarity among treatments was small after bacterial community similarity clustering analysis,and citrus yield increased somewhat after CSF fertilization reduction.When CSF fertilization reduced by 30%,citrus yield increased by 4. 50%. When CSF fertilization reduced by 40%,citrus yield decreased by4. 14%. After CSF fertilization,citrus quality did not change significantly in CSF conventional fertilization and reduction of 10% and 40%,while significantly decreased in 20% and 30% of fertilization reduction. [Conclusion] CSF fertilization reduction changed the diversity of soil bacterial community structure and the yield and quality of citrus. | Men Shuhui Ding Fangjun Zhang Hong Ke Chao Zhang Shiwei Huang Zhanbin | 2018 | Meteorological and Environmental Research2018，9，6： | 1 |
| 17 | Advances in Application of Models in Soil Quality Evaluation显示文摘Soil quality is a comprehensive reflection of soil properties.Since the soil quality concept was put forward in the 1970s,the quality of different type soils in different regions have been evaluated through a variety of evaluation methods,but it still lacks universal soil quantity evaluation models and methods.In this paper,the applications and prospects of grey relevancy comprehensive evaluation model,attribute hierarchical model,fuzzy comprehensive evaluation model,matter-element model,RAGA-based PPC /PPE model and GIS model in soil quality evaluation are reviewed. | SI Zhi-guo WANG Ji-jie YU Yuan-chun LIANG Guan-feng CHEN Chang-ren SHU Hong-lan | 2012 | Asian Agricultural Research2012，4，11： | 1 |
| 18 | Land reclamation pattern of iron mine in Tangshan显示文摘Based on the analyses of the character of the exploitation of the iron ore resource and its destruction of eco-environment in Tangshan area, this paper puts forward the patterns of land reclamation which fits for this area. The patterns include the reclamation of ecological agriculture, planting directly on the tailing bin without covering soil, reclamation of mine tailings in the pool, and improvement of the soil quality by using tailings etc. Now, over 700hm^2 land has been reclaimed by taking advantage of the pattern in Tangshan and eight typical reclamation districts have been built. The rates of reclamation exceed 80% and have reached the advanced level of the world. Practice has proved that the eco-environment of the ore area has been greatly improved and the remarkable economic and social benefits have been gained. | LI Fu-ping~(1,2), LIU Ren-yi~(2), ZHANG Jin-rui~(1,2), GUO Qiao-zhen~(2), WANG Hong-xin~(2) (1. University of Science and Technology Beijing, Beijing 100083, China 2. Hebei Institute of Technology, Tangshan 063009, China) | 2005 | 中国有色金属学会会刊:英文版2005，15，S1： | 0 |
| 19 | Status of Water Quality in Mt. Elgon, Cherangany Forested Ecosystems and entire River Nzoia Catchment in Kenya显示文摘Water availability for both domestic and industrial use is a major growing problem in the developing countries including Kenya. The situation is further worsened by increasing human population and climate change, probably the most complex environmental problem facing the world today. Mt. Elgon and Cherangany hills forest ecosystems in the River Nzoia Catchment are threatened by the increase in local population. This is causing environmental degradation and disruption in the catchment areas resulting in drying up of streams and rivers and both water and soil pollution. The objective of this study was to conduct a baseline survey to provide information on the status of water quality in the River Nzoia Catchment and an overview of pollution levels, sources and possible mitigation measures. The study was carried out in August 2017 during the short rains. Water and sediments from 26 spatially distributed sites on rivers in the catchment were sampled and analyzed. The water quality (physical and chemical) was assessed through analysis of water and sediments. Both water and sediments were analyzed following the standard analytical methods. All the rivers in the watersheds forming the River Nzoia catchment contained high levels of iron in water which exceeded permitted levels for drinking without treatment and for domestic uses in the environmental. In addition, the turbidity levels of water were beyond accepted limits set for drinking water and environmental water standards. There was little pollution of water from heavy metals. River Nzoia near Webuye town and Sigomre bridge were the most polluted waters with levels of nitrates, iron, copper, chromium, with BOD (Biological Oxygen Demand) and COD (Chemical Oxygen Demand) exceeding the accepted limits in the environment. For sediments, the contents of copper, magnesium and iron were high in the upper catchment of River Nzoia (foot slopes of Mt. Elgon). The levels of nitrates and phosphates in the sediments were high in the lower parts of the catchment. The recommended interventions to manage point or non-point pollution sources include: land and soil conservation to reduce erosion, precision in fertilizer usage, proper sewage and industrial effluent treatment and disposal. The mitigation measures should be at the sub-catchment level to reduce land, soil and water pollution. Technologies for soil and water conservation including afforestation on bare lands, control of overland flow, reduction on river bank cultivation and conservation agriculture practices will reduce pollution and conserve the environment. | Stanley Nadir Victor Jaoko Phesto Osano Paul Ongugo | 2019 | Journal of Environmental Science and Engineering(B)2019，8，2： | 0 |
| 20 | EFFECTS OF SOIL MOISTURE CONTENT ON DRY NURSERY SEEDLING QUALITY OF LATE DOUBLE CROPPING RICE IN SOUTH CHINA显示文摘In the present paper, an experiment was conducted to study the effects of soil moisture content on dry nursery seedling quality in Guangzhou in 1995. Through comparing the difference of dry nursery seedlings and wet nursery seedlings, we found a close relationship between soil moisture content and seedling growth. The seedling emergence of dry nursery seedling was more even, tidy and faster, and the survival rate was higher than that of wet nursery seedling. Dry nursery seedlings had small plant stature, slow leaf stretching speed and low individual seedling dry weight, but had high dry/fresh weight ratio. This was abeneficial factor for seedlings to recover from transplanting shock more quickly. As com-pared with the wet nursery seedlings, dry nursery seedlings had poor rooting ability,but had more vigorous white roots and fewer rust roots. It was the possibly important reasonfor dry nursery seedlings to form strong“explosive force”. | Zhang Xu Huang Nongrong Kong Qingni Lin Daoxuan Liu YanzhuoRice Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640Cai Hanxiong Liang Quan Liang Youqiang Liang ChengyingCereal and Oil Crop Production Section, Agricultural Department of Guangdong Province, Guangzhou 510500 | 1996 | 热带亚热带植物学报1996，4，S1： | 0 |
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