• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    The efficiency of long-term straw return to sequester organic carbon in Northeast China’s cropland

    2018-02-05 07:10:55WANGShichaoZHAOYawenWANGJinzhouZHUPingCUlXianHANXiaozengXUMinggangLUChangai
    Journal of Integrative Agriculture 2018年2期
    關(guān)鍵詞:癌病流膠病櫻桃樹

    WANG Shi-chao, ZHAO Ya-wen, WANG Jin-zhou, ZHU Ping, CUl Xian, HAN Xiao-zeng, XU Minggang, LU Chang-ai

    1 Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land, Beijing 100081, P.R.China

    2 Jilin Academy of Agricultural Sciences, Changchun 130124, P.R.China

    3 Heilongjiang Academy of Agricultural Sciences, Heihe 164300, P.R.China

    4 Northeast Institute of Geography and Agro-ecology, Chinese Academy of Sciences, Harbin 150081, P.R.China

    1. lntroduction

    Soil contains the largest carbon (C) pool of the global terrestrial ecosystem. The total soil organic carbon (SOC)pool is approximately 1 500 Pg C, which is three times that of the atmospheric carbon pool (Songet al.2014). Soil organic matter (SOM) not only plays a vital role in global carbon cycling, but also contributes considerably to improvements in soil quality, crop production, and terrestrial ecosystem health(Wanget al.2008; Luet al.2009). However, increasing SOM has become a major global problem (Fanet al.2013;Keesstraet al.2016). SOC dynamics are strongly influenced by agricultural management practices, such as fertilization,crop residue return, and tillage (Luet al.2009; Luoet al.2010; Louet al.2011; Ouyanget al.2013; Douet al.2016).

    It has recently been proposed that straw input can lead to SOC accumulation and improvements in soil structure(Luet al.2009; Liu Cet al.2014; Lu 2015; Wanget al.2015a). For example, Liu Cet al.(2014) found that straw return increased SOC by 12.8%, with a 42.0% increase in the active C fraction after 22 years. Previous research has also demonstrated that continuous straw return boosts SOC accumulation in early years, but that these effects decrease after a decade (Liu Cet al.2014; Wanget al.2015a).Specifically, Liu Cet al.(2014) reported that straw return enhanced SOC sequestration over the first three years, but that these effects were minimal in the experimental site after 15 years. However, opposing results have also been reported(Pittelkowet al.2015), which may be attributed to different environmental conditions, land management approaches,and soil types. Additional factors, such as straw-C input rate,number of cultivation years, initial SOC levels, and methods for straw disposal, are also critical in explaining why certain soil carbon pools react differently to straw return. Therefore,evaluating the changes in SOC under long-term cultivation would be beneficial for determining how land management practices influence soil and global carbon cycling.

    The black soil of Northeast China is one of the main crop production areas in the country, and provides a third of the country’s grain commodity. The black soil area covers 1.1×108ha, including arable land (2.4×107ha in Heilongjiang Province, 1.1×107ha in Jilin Province, 0.6×107ha in Liaoning Province, and 0.6×107ha in Inner Mongolia) that is characterized by black soil (Mollisols) which is rich in organic matter (Liang A Zet al.2011; Zhanget al.2013). The large amount of agricultural straw that is produced in this region every year is not fully utilized. Instead of being returned to the soil, the straw is usually used as livestock feed or to provide energy for heating (Douet al.2016). Hence, soil degradation,a result of the loss of SOC and nutrients, is a considerable challenge for sustainable cultivation in this region (Liuet al.2010), as intensive cultivation has reduced SOC by 50%over about 60 years of tillage (Yuet al.2006), with a loss of 0.5% each year (Liuet al.2010). Rather than being used to provide energy, the organic material of straw could be used to promote the SOC stock. Many studies have investigated how straw return affects soil fertility (Yanet al.2007; Sun Bet al.2013). However, the approach of using straw return to reverse SOC reduction faces some problems. For example,the extent we depend on straw return to improve SOC is unknown. Also, the short- and long-term effects of using straw return to improve SOC in the black soil region in China have not been assessed.

    Long-term experiments can provide reliable data for assessing and predicting the influence of straw return on SOC sequestration and soil fertility. There is currently minimal knowledge about the influence of different environmental conditions on the long-term effects of straw return (Dinget al.2014; Songet al.2014), and limited research has focused on black soils. In this study, we used long-term field experiments in Northeast China to study the influence of straw return on SOC. The objectives of this study were: 1) to analyze the SOC dynamics of longterm straw return; 2) to examine the relative contribution of straw return to SOC sequestration; and 3) to evaluate the sustainability of straw return for improving SOC and straw-C sequestration efficiency. We hypothesized that straw return could efficiently increase the SOC stock of the black soil region in Northeast China. However, we also expected clear differences among different regions in Northeast China.

    2. Materials and methods

    2.1. Site description

    This study was conducted at three different sites in the Northeast China: Heihe (50°15′N, 127o27′E); Hailun(47°27′N, 126°55′E); and Gongzhuling (43°30′N, 124°48′E)(Fig. 1, Table 1). Three long-term straw return experiments with different fertilization treatments were initiated in 1979,1990, and 1990 for Heihe, Hailun, and Gongzhuling,respectively. Prior to the experiment, the field was under crop production for at least 60 years at Gongzhuling site, 110 years at Hailun site, or 150 years at Heihe site. The soil at all three sites originated from quaternary loess-like sediments.The study sites are characterized by a temperate sub-humid climate. The average annual precipitation is 528 mm, with most of the rainfall occurring from July to September. The frost-free period ranges from 105 days at the Heihe site to 140 days at the Gongzhuling site. Crop rotations include wheat (Triticum aestivumL.)/soybean (Glycine max(L.)Merrill.) at the Heihe site, wheat/maize (Zea maysL.)/soybean at the Hailun site, and a mono-cropping system with maize at the Gongzhuling site. Each year, spring wheat seeds are sown in strips in early April and harvested in mid-August. Soybean seeds are sown in holes in early May and harvested in late September. Maize seeds are sown in holes in early May and harvested in early October. The average annual temperature ranges from –0.5°C at Heihe to 4.5°C at Gongzhuling. Soil textures are clay loam, heavy loam, and loamy clay soil at Heihe, Hailun and Gongzhuling,respectively. The fine mineral contents were 33.4% (Heihe),34.5% (Hailun), and 31.1% (Gongzhuling). All sites had black soils, with initial SOC contents between 13.5–31.3 g kg–1, initial total nitrogen (TN) contents between 1.24–2.23 g kg–1, and soil pH values between 6.1–7.6 (Table 1).

    Fig. 1 Locations of the study sites in Northeast China.

    2.2. Experimental design and sampling

    Three treatments were implemented at each site: (1) no fertilization (CK); (2) inorganic fertilization N, P and K (NPK);and (3) NPK plus straw return (NPKS). The plots were arranged in a randomized block design, and each treatment was replicated three times. The plot sizes were 212 m2at Heihe, 224 m2at Hailun, and 400 m2at Gongzhuling.The chemical fertilizer and straw input rates are in Table 2.The applied chemical fertilizers included urea, calcium superphosphate, and potassium sulfate, with the exception that no potassium fertilizer was used at the Heihe site. The application rates of inorganic fertilizer for each growing season ranged from 37.5 to 245.3 kg N ha–1, 16.4 to 62 kg P ha–1, and 0 to 68.5 kg K ha–1(Table 2).

    The aboveground straw was removed from the CK and NPK treatments after each harvest (around October 10th).In the NPKS treatment, which included straw return, the aboveground straw was removed after each harvest and re-incorporated into the soil. At the Heihe and Hailun sites,wheat/maize/soybean organic material was returned by deep plowing, while at the Gongzhuling site maize straw was used for mulching material. The average annual rates of straw return were 3.0, 4.5, and 7.5 Mg ha–1(dry weight) at the Heihe, Hailun, and Gongzhuling sites, respectively. Straw was applied after cutting it into pieces of 5–15 cm length after harvesting. The amounts of C (straw-C and root-C) added to soil were 0.44–1.97 Mg ha–1at Heihe, 1.59–3.35 Mg ha–1at Hailun, and 4.4–5.9 Mg ha–1at Gongzhuling (Fig. 2).

    2.3. Soil analysis

    Surface soil samples (0–20 cm depth) were collected from each treatment plot after each harvest (around October 10th),after which they were air-dried and sieved through either a 1-mm mesh for pH and available P analyses or a 0.15-mm mesh for organic matter, total N, and total P analyses. Soil organic matter was determined by quantifying the oxidizable soil carbon in a heated dilution of K2Cr2O7subjected to a volumetric oxidation method (Nelson and Sommers 1996).Soil available P was measured using Olsen’s method (Van Reeuwijk 2002), while total nitrogen was measured using the micro-Kjeldahl digestion, distillation, and titration method(Bremner and Mulvaney 1982). All results were normalized to a dry mass basis. The soil bulk density (g cm–3) was determined by the core sampler method described by Piper(1966). We also collected soil samples from the 0–20 cm layer at the beginning of this study, in 1979, 1990, and 1990 for the Heihe, Hailun, and Gongzhuling experiments,respectively. These samples were analyzed to determine the basic physical and chemical properties.

    2.4. Calculation of C sequestration rate and C sequestration efficiency

    SOC stock (Mg ha–1) was calculated using the following equation:

    ?

    Where, C is SOC content (g kg–1), BD is soil bulk density (g cm–3), anddis soil depth(m). In this study, we only calculated SOC stocks for the top layer of soil (0–20 cm).

    The annual SOC changes (DSOC, Mg C ha–1yr–1) were calculated using the following equation:

    全區(qū)櫻桃產(chǎn)業(yè)發(fā)展的專業(yè)化、專職化的人才團(tuán)隊(duì)十分匱乏,嚴(yán)重制約烏當(dāng)櫻桃產(chǎn)業(yè)的發(fā)展壯大。在全區(qū)各政府部門中,農(nóng)業(yè)局負(fù)責(zé)統(tǒng)籌全區(qū)櫻桃全產(chǎn)鏈發(fā)展,專業(yè)、專職農(nóng)業(yè)技術(shù)推廣人才團(tuán)隊(duì)成員約5名,在數(shù)量和專業(yè)結(jié)構(gòu)上都遠(yuǎn)遠(yuǎn)不能滿足發(fā)展好3.6萬余畝櫻桃種植基地及中下游產(chǎn)業(yè)的需求。烏當(dāng)櫻桃產(chǎn)業(yè)正面臨著很多技術(shù)瓶頸,特別是在病蟲害防治方面,如下壩鎮(zhèn)出現(xiàn)櫻桃根癌病、流膠病、病毒病及果實(shí)褐腐病等,造成櫻桃樹勢衰退和減產(chǎn),嚴(yán)重時(shí)成片死亡,而現(xiàn)有人員的技術(shù)能力難以有效解決這一問題。

    Where, SOCTand SOC0represent the SOC stock at the end and beginning of a year, respectively, andtis the duration of the experiment in years.

    The relative changes of SOC stock are represented as SOCNPKS(or SOCNPK) minus SOCCK, and the relative contribution (RC) of straw return to the soil was calculated using the following equation:

    The carbon sequestration rate (CSR, Mg C ha–1yr–1) was calculated using the following equation:

    Where, DSOCTand DSOC0represent the respective annual change in the SOC stock of a particular treatment (CK, NPK, or NPKS). DSOCTdescribes the DSOC aftertyears of experiments whereas DSOC0represents the DSOC at the beginning of a year.

    The carbon sequestration efficiency (CSE) for each paired-trial was calculated as follows:

    Where, SOCNPKis the SOC stock of the NPK treatment, SOCNPKSis the SOC stock of the NPKS treatment, and TSC is the total straw C input (Mg C ha–1) over the duration of the experiment.

    2.5. Statistical analyses

    Analysis of variance (ANOVA) and multiple comparisons were performed in SAS (ver.8.1, SAS Institute Inc., Cary, NC, USA) to identify between treatment differences in SOC sequestration, carbon sequestration rate, and/or straw-C sequestration efficiency of the topsoil. If the ANOVA results were significant, further comparisons using leastsquares differences were conducted in SAS. A correlation analysis was carried out in SPSS (ver. 17.0, IBM, Armonk, NY, USA) to examine how different treatments affected various factors, e.g., soil C/N ratio, initial SOC (ISOC), available phosphorus (AP),pH, the cumulative straw-C input (SC), SC/ISOC ratio, the SC/SMBC (soil microbial biomass carbon) ratio, and cultivation year, and to construct the soil organic carbon sequestration property matrix.

    3. Results

    3.1. Changes in the SOC stock under straw return

    The SOC stock of CK treatment plots at the three sites decreased throughout the entire long-term experiment period (Fig. 3). In this study, the SOC stocks of NPKS treatment plots varied between 31.7 and 58.3 Mg ha–1. When compared to the CK treatment plots, the SOC stock of NPKS treatment plots increased, on average, by 11.7% (Heihe site), 3.0% (Hailun site), and 7.0% (Gongzhuling site), respectively. The SOC stocks of NPKS plots were 4.0 and 5.7% higher than those of the NPK plots at the Hailun and Heihe sites, respectively. However, the straw return, when compared with the NPK treatment, did not significantly affect the SOC stock at the Gongzhuling site. These results demonstrate that long-term NPKS treatment maintained, and sometimes increased SOC, while long-term NPK treatment maintained (or slightly decreased) SOC compared with the original SOC stock. On the other hand, a lack of fertilization (CK treatment) tended to decrease SOC stocks.

    The DSOC values for the fertilization treatments were≥0, while the CK treatment showed negative DSOC values(Fig. 4). The DSOC values ranged from –1.65 to 6.60 Mg C ha–1, with an average of –0.05 Mg C ha–1. The DSOC values for the three treatments at the Heihe and Hailun sites were ranked as NPKS>NPK>CK, while an equilibrium state between the three treatments was observed at Gongzhuling.At the Heihe site, the DSOC values for the NPKS and NPK treatments were 102.0 and 41.8% higher, respectively, than the DSOC value for the CK treatment. Both of the fertilization treatments significantly increased DSOC compared to the CK treatment (P<0.05). In addition, both fertilization treatments at the Hailun site, when compared to the CK treatment,significantly increased DSOC (P<0.05). The initial DSOC value for the NPK treatment was higher than that for the NPKS treatment. However, the NPK treatment showed a five-fold decrease in DSOC over 5 years at the Gongzhuling site. In contrast, the DSOC value for the NPKS treatment remained stable over the course of the experiment.

    Table 2 Fertilizer inputs for each treatment

    Fig. 2 Changes in straw-C inputs and reclamation years at three experimental sites in Northeast China.

    3.2. Soil carbon sequestration rate in response to straw return

    As expected, straw return primarily enhanced CSR at the Heihe site, relative to the Gongzhuling and Hailun sites(Fig. 5). The CSR value decreased over time at the Heihe site. In addition, straw return had a significant effect on CSR at the Heihe site (F=6.28,P=0.02); CSR ranged from 0.24 to 1.50 Mg C ha–1yr–1, compared with 0.15–0.50 Mg C ha–1yr–1for NPK. The Hailun site also showed a decreasing trend in CSR over time. However, at this site, both fertilization regimes yielded similar CSR values ((0.32±0.23) Mg C ha–1yr–1) (Fig. 5-C). At the Gongzhuling site, the NPK treatment resulted in a significantly higher CSR value ((0.84±1.08)Mg C ha–1yr–1,F=7.8,P<0.05) than the NPKS treatment((0.11±0.24) Mg C ha–1yr–1) (Fig. 5-D). Regression analysis results showed that the CSR for the NPKS treatments equated to cultivation times of 17, 11, and 8 years at the Heihe, Hailun and Gongzhuling sites, respectively. This result indicates that the CSR of the black soils in northeastern China is close to a stable equilibrium state.

    Fig. 3 Soil organic carbon (SOC) stocks for different fertilization treatments, as well as initial condition, at the three sites over the whole experimental period. CK, no fertilizer application;NPK, inorganic fertilization N, P and K; NPKS, NPK plus straw return. The results are presented as mean values with standard deviations (Heihe, n=11; Hailun, n=16; Gongzhuling,n=19). Mean values with different letters represent statistically significant differences (P<0.05).

    3.3. Straw-C sequestration efficiency

    The CSE calculated for the Heihe site (46.8%) was significantly higher than the calculated values for the Hailun(13.3%) and Gongzhuling (–1.6%) sites (P<0.01) (Fig. 6-A).The CSE ranged from –22.1 to 97.1% over 1–33 years. On average, (15.3±27.8)% of the straw-C input was converted to SOC. In addition, the CSE at the Heihe and Hailun sites decreased exponentially as cultivation increased, appearing to attain equilibrium at the end of the experiments (Fig. 6-B).The CSE at the Gongzhuling site, on the other hand,consistently remained in a steady state. The regression analyses for the Hailun and Heihe sites show that after a continual decline for 13 and 17 years respectively, the CSE remained stable at 1.0–6.0% and 15.6–38.8%, respectively.At the Gongzhuling site, CSE remained at approximately 0% over 18 years.

    Fig. 4 Annual soil organic carbon (DSOC) changes for different fertilization treatments. CK, no fertilizer application; NPK,inorganic fertilization N, P and K; NPKS, NPK plus straw return;HH, Heihe site; HL, Hailun site; GZL, Gongzhuling site.

    4. Discussion

    4.1. lmpact of straw return on the SOC stock

    Fig. 5 Soil carbon sequestration rate (CSR) under different fertilization treatments. A, all three experiment sites. Box-and-whisker diagrams show the median, 5th, 25th, 75th and 95th percentiles for CSR. The solid lines represent median values and the short dashed lines represent mean values. B, Heihe site. C, Hailun site. D, Gongzhuling site.

    Fig. 6 Straw-C sequestration efficiency (CSE) in the treatment with straw. A, the range of CSE at different sites. Box-and-whisker diagrams show the median, 5th, 25th, 75th and 95th percentiles for CSE. The solid lines represent median values and the short dashed lines represent mean values. B, variation with cultivation year of CSE at three sites. All, three experiment sites; HH, Heihe site; HL, Hailun site; GZL, Gongzhuling site.

    Our experiments showed that the application of fertilizer(NPK and NPKS treatments), when compared to the CK treatment, led to higher SOC stocks in absolute terms(Fig. 7) Straw return at the high SOC density site (Heihe)was an exception, as SOC rapidly increased during the earlier stages of the experiment only to decline in the later stages. Although the SOC stocks at the Hailun site only changed slightly and gradually increased at the Gongzhuling site (Fig. 8), straw-C input has been shown to be more effective than NPK and CK treatments in driving microbial activity (Majumder and Kuzyakov 2010; Bastidaet al.2013). This difference may stem from the shorter history of reclamation, lower straw-C input, and higher SOC density at the Heihe site relative to the other two sites(Figs. 2 and 7) (Lehtinenet al.2014; Lu 2015; Poeplauet al.2015). At Heihe, the SOC stock could continue to decrease for 50 years under natural conditions (Yuet al.2006). Furthermore, the SOC increase could probably be related to an increase of the C input (Duiker and Lal 1999;Panet al.2003; Wiesmeieret al.2015); in Hailun and Heihe,stagnating C inputs over time led to a constant SOC level(Hailun) or even a decline of SOC (Heihe). This is in line with our results that stagnating C inputs in agricultural soils led to SOC decreases over longer periods. On the other hand, temperature increases and low precipitation caused by climate change will result in intensified decomposition of native SOC (Wiesmeieret al.2016). The effects of straw return on improving SOC at the Heihe and Hailun sites were not evident, probably due to the increasing temperature over the experimental period (Fig. 9).

    It is worth emphasizing that straw return increased SOC stocks in this region by either 6% (when compared to fertilized plots) or 12% (when compared to unfertilized plots)(Fig. 7-B). Interestingly, straw return increased SOC stocks by 5.7% in Northeast China, a result that was lower than previously reported values for upland soils in China (9.9%),Europe (7%), and North America (10.8%) (Powlsonet al.2011; Lehtinenet al.2014; Wanget al.2015a). Overall,straw return had a relatively weak effect on the SOC stocks in Northeast China.

    Fig. 7 Average relative changes in soil organic carbon (SOC) stocks for two different fertilization management practices over the experimental period. A, all three experiment sites. B, Heihe. C, Hailun. D, Gongzhuling. NPK, inorganic fertilization N, P and K;NPKS, NPK plus straw return; ?NPKS, NPKS minus NPK. Different letters indicate statistically significant differences at P<0.05.Box-and-whisker diagrams show the median, 5th, 25th, 75th and 95th percentiles for relative change in SOC stocks. The solid lines represent median values and the short dashed lines represent mean values.

    Fig. 8 Soil organic carbon (SOC) stock dynamics under straw return in the black soils at the three long-term experimental sites.A, Heihe. B, Hailun. C, Gongzhuling.

    4.2. Factors regulating straw-C sequestration efficiency

    Our findings show that the average for all sites straw-C sequestration efficiency was 15.3% over the experimental duration of 33 years (Fig. 6). This CSE value is in agreement with a previously reported average CSE (15.9%) value for the upland area of northern China (Zhanget al.2010), but lower than the CSE (30%) value reported for upland India by Srinivasaraoet al.(2012). In contrast, the CSE value for wheat and maize crops has been reported to be only 7.6%in the USA (Konget al.2005). The differences in straw-C sequestration efficiency are mainly related to soil fertility,climate, and cultivation (Luoet al.2010; Ouyanget al.2013).The CSE value for Northeast China was correlated with soil C/N, available P, pH, reclamation year, SC/SOC, SC/SMBC, mean annual temperature, and annual precipitation(Tables 3 and 4).

    Microbial communities differ based on climatic conditions,with the climate in Northeast China potentially affecting the structure of the microbial community, which can influence the rate of straw decomposition (Sun Bet al.2013). Straw addition clearly improved the carbon content and CSE in the northern region (Heihe), and this result was probably due to this site having a shorter cultivation history (Fig. 2),higher SOC content, and lower inputs of C relative to the other studied sites.

    Our data indicated that the CSE value was significantly higher at the Heihe site (46.8%) than at the Hailun (13.3%)or Gongzhuling (?1.6%) sites (P<0.01). Soil carbon sequestration may be restricted by certain aspects of initial soil quality associated with low inputs of C, such as initial SOC content, pH, or the total carbon and nitrogen ratios(Wanget al.2015b). Despite corroborating Wangetal.(2015b) that reported a significant correlation between changes in SOC and the amount of C input, a comparison of data from different experimental sites suggests that the continuous maize system in Gongzhuling is less efficient at sequestering C from added C inputs than systems that include wheat and/or soybean. Gongzhuling had the lowest CSE value of all three sites, a finding that is likely a consequence of a long history of reclamation (Fig. 2), and the high input of C (straw mulch at Gongzhuling site) coupled with low SOC density. However, straw return can accelerate the turnover rate of native soil organic carbon and introduce large amounts of labile C, such as microbial biomass carbon(Jenkinsonet al.1985; Kuzyakovet al.2000; Blagodatskaya and Kuzyakov 2008) and water-soluble organic carbon(WSOC) (Guenetet al.2012; Zhanget al.2012; Kirkbyet al.2014; Anet al.2015). Previous research in Gongzhuling has shown that NPKS treatment, when compared to CK treatment, increased WSOC content by 40.1% (Zhenget al.2006; Liang Yet al.2011). Furthermore, Pang and Huang(2006) showed that straw mulch can significantly improve SOC content at the soil surface, but can also impede straw decomposition and the accumulation of SOC.

    Fig. 9 Mean annual temperature and mean annual precipitation at three experimental sites in our studied regions.

    4.3. How to improve long-term straw-C sequestration with straw return in black soil

    Our results showed that the equilibrium value of CSR equated to cultivation times of 17, 11, and 8 years for the NPKS treatment at the Heihe, Hailun, and Gongzhuling sites, respectively. These relatively short time could cause apparent new equilibrium states, which could be related to the C saturation status of the investigated soils (Wiesmeieret al.2014). Significantly positive linear correlations between SOC stocks for the NPKM treatment at the three sites and experiment duration (Fig. 10) indicated that the black soil was not saturated in C sequestration. Moreover,a significant increase in SOC stock at Hailun was also observed with higher organic manure input after 10 years(Dinget al.2014). The degree of increase in SOC was lower in the NPKS treatment compared to the NPKM treatment in our study area and did not reach the saturation level; this result was explained by different net carbon production rates(accumulation of straw derived SOC and decomposition of old C) with straw return. After the SOC equilibrium, CSE cannot improve further. Interestingly, when the relationships among CSE and soil properties, climatic factors, amount of straw returned, and the cropping system are investigated(Tables 3 and 4), CSE has the strongest correlation with SMBC and soil availability. However, the most effective way to translate straw return into soil C sequestration still remains unclear.

    Previous studies have found that the major limiting factors of increasing SOC under straw return conditions include tillage, fertilization practices, and cropping system(Liang A Zet al.2011; Mathieuet al.2015). For example,the application of organic manure may stimulate the decomposition of added straw-C due to increased microbial biomass (Kuzyakow 2010). In addition, a laboratory experiment (25°C incubation over 95 days) by Aitaet al.(2012), in which both manure and straw were added to thesystem, found that the mineralization of straw-C accelerated by 24% over 95 days compared to a treatment in which only straw was added. This resulted in higher SOC stock and positive effects for soil fertility. Similarly, Zhanget al.(2017)observed an increase in SOC variables after coupling the long-term application of nitrogen fertilizer with straw return.These findings suggest that the optimized fertilization with straw return leads to higher SOC content.

    Table 3 Correlation coefficients between straw-C sequestration efficiency (CSE) and soil factors in Northeast China1)

    Table 4 Correlation coefficients between straw-C sequestration efficiency (CSE), cultivation years and climatic factors1)

    Fig. 10 Soil organic carbon (SOC) stock dynamics under the N, P, K fertilizer in combination with manure (NPKM) treatment in the black soils at the three long-term experimental sites.

    It is also important to consider cultivation modes that may affect straw-C sequestration. The combination of no-tillage and straw mulching resulted in a loss of straw-C,as the straw was left on the soil surface (Luet al.2009).According to a meta-analysis, a no-tillage approach had a 9% advantage over chopped straw in straw return situations,which increased to 12% with plough tillage, and to 16%with rotary tillage (Lu 2015). These increases occurred because straw buried in deep soil layers is favorable for straw-C sequestration (Caiet al.2015). Reasonable crop rotation (e.g., rotated soybean) can also improve the decomposition and transformation of straw-C returned to soil, as this could provide the nitrogen necessary for microorganism activity (Liu Set al.2014).

    Overall, reasonable agronomic management practices,such as ploughing and rotary tillage, crop rotation, and optimized fertilization, have a significant effect on straw-C sequestration, but their long-term effects should be further investigated in future studies.

    5. Conclusion

    The results from our study indicate that the SOC stocks of black soil in the southern region of Northeast China were approximately at a stable equilibrium state, whereas the SOC stocks continued to decrease in the northern region. Furthermore, the rate of change of SOC stocks was directly related to the initial SOC density. Straw return and fertilization enhanced soil carbon sequestration in the northern and high latitude regions that were characterized by high SOC density, but the input of straw maintained the SOC stocks at a stable state in the southern region.However, a longer period of straw return would result in a very low or even negative CSE after which SOC would not increase further. Additional variables, such as reasonable agronomic management practices, i.e., tillage, rotation, and optimized fertilization, should be considered if the objective is a long-term improvement in the straw-C sequestration in black soil.

    Acknowledgements

    This work was financially supported by the National Basic Research Program of China (973 Program, 2013CB127404)and the Collaborative Innovation Action of Scientific and Technological Innovation Project of the Chinese Academy of Agricultural Sciences. We are grateful to the staff that worked on the project, and contributed to the field management of the long-term experiments.

    An T, Schaeffer S, Zhuang J, Radosevich M, Li S, Li H, Pei J, Wang J. 2015. Dynamics and distribution of13C-labeled straw carbon by microorganisms as affected by soil fertility levels in the Black Soil region of Northeast China.Biology and Fertility of Soils, 51, 605–613.

    Bastida F, Torres I F, Hernández T, Bombach P, Richnow H H, García C. 2013. Can the labile carbon contribute to carbon immobilization in semiarid soils? Priming effects and microbial community dynamics.Soil Biology and Biochemistry, 57, 892–902.

    Bremner J M, Mulvaney C S. 1982. Nitrogen-total. In: Page L A, Milley R H, Keeney D R, eds.,Methods of Soil Analysis.American Society of Agronomy, Madison. pp. 595–642.

    Blagodatskaya E, Kuzyakov Y. 2008. Mechanisms of real and apparent priming effects and their dependence on soil microbial biomass and community structure: Critical review.Biology and Fertility of Soils, 45, 115–131.

    Cai M, Dong Y J, Chen Z J, Kalbitz K, Zhou J B. 2015. Effects of nitrogen fertilizer on the composition of maize roots and their decomposition at different soil depths.European Journal of Soil Biology, 69, 43–50.

    Ding X, Yuan Y, Liang Y, Li L, Han X. 2014. Impact of long-term application of manure, crop residue, and mineral fertilizer on organic carbon pools and crop yields in a Mollisol.Journal of Soils and Sediments, 14, 854–859.

    Dou X, He P, Zhu P, Zhou W. 2016. Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes.Scientific Reports,6, 21488.

    Duiker S W, Lal R. 1999. Crop residue and tillage effects on carbon sequestration in a Luvisol in central Ohio.Soil and Tillage Research, 52, 73–81.

    Fan M, Lal R, Gao J, Qiao L, Su Y, RF J, Zhang F. 2013.Plant-based assessment of inherent soil productivity and contributions to China’s cereal crop yield increase since 1980.PLOS ONE, 8, 1–11.

    Guenet B, Juarez S, Bardoux G, Abbadie L, Chenu C. 2012.Evidence that stable C is as vulnerable to priming effect as is more labile C in soil.Soil Biology and Biochemistry,52, 43–48.

    Jenkinson D S, Fox R H, Rayner J H. 1985. Interactions between fertilizer nitrogen and soil nitrogen - the so-called‘priming’ effect.Journal of Soil Science, 36, 425–444.

    Keesstra S D, Bouma J, Wallinga J, Tittonell P, Smith P,Cerdà A, Montanarella L, Quinton J N, Pachepsky Y,van der Putten W H, Bardgett R D, Moolenaar S, Mol G,Jansen B, Fresco L O. 2016. The significance of soils and soil science towards realization of the United Nations Sustainable Development Goals.Soil, 2, 111–128.

    Kirkby C A, Richardson A E, Wade L J, Passioura J B, Batten G D, Blanchard C, Kirkegaard J A. 2014. Nutrient availability limits carbon sequestration in arable soils.Soil Biology and Biochemistry, 68, 402–409.

    Kong A Y Y, Six J, Bryant D C, Denison R F, van Kessel C.2005. The relationship between carbon input, aggregation,and soil organic carbon stabilization in sustainable cropping systems.Soil Science Society of America Journal, 69, 1078.

    Kuzyakov Y, Friedel J K, Stahr K. 2000. Review of mechanisms and quantification of priming effects.Soil Biology and Biochemistry, 32, 1485–1498.

    Kuzyakov Y. 2010. Priming effects: interactions between living and dead organic matter.Soil Biology and Biochemistry,42, 1363–1371.

    Lehtinen T, Schlatter N, Baumgarten A, Bechini L, Krüger J,Grignani C, Zavattaro L, Costamagna C, Spiegel H. 2014.Effect of crop residue incorporation on soil organic carbon and greenhouse gas emissions in European agricultural soils.Soil Use Manage, 30, 524–538.

    Liang A Z, Zhang X P, Yang X M, Fang H J, Shen Y, Li W F.2011. Distribution of soil organic carbon and its loss in black soils in Northeast China.Chinese Journal of Soil Science,39, 533–538. (in Chinese)

    Liang Y, Han X, Song C, Li H. 2011. Impacts of returning organic materials on soil labile organic carbon fractions redistribution of Mollisol in Northeast China.Scientia Agricultura Sinica, 44, 3565–3574. (in Chinese)

    Liu C, Lu M, Cui J, Li B, Fang C. 2014. Effects of straw carbon input on carbon dynamics in agricultural soils: A metaanalysis.Global Change Biology, 20, 1366–1381.

    Liu S, Jia S, Zhang X, Chen X, Zhang S, Sun B, Chen S, Dou Y. 2014. Effects of corn and soybean residues return on microbial biomass and respiration in a black soil.Soil and Crop, 3, 105–111. (in Chinese)

    Liu X, Zhang Y, Wang Y, Sui Y, Zhang S, Herbert S, Ding G. 2010. Soil degradation: A problem threatening the sustainable development of agriculture in Northeast China.Plant Soil Environment, 56, 87–97.

    Lou Y, Xu M, Wang W, Sun X, Zhao K. 2011. Return rate of straw residue affects soil organic C sequestration by chemical fertilization.Soil Tillage Research, 113, 70–73.

    Lu F. 2015. How can straw incorporation management impact on soil carbon storage? A meta-analysis.Mitigation and Adaptation Strategies for Global Change, 20, 1545–1568.

    Lu F, Wang X, Han B, Ouyang Z, Duan X, Zheng H, Miao H. 2009. Soil carbon sequestrations by nitrogen fertilizer application, straw return and no-tillage in China’s cropland.Global Change Biology, 15, 281–305.

    Luo Z, Wang E, Sun O J. 2010. Can no-tillage stimulate carbon sequestration in agricultural soils? A meta-analysis of paired experiments.Agriculture,Ecosystems & Environment, 139,224–231.

    Majumder B, Kuzyakov Y. 2010. Effect of fertilization on decomposition of14C labelled plant residues and their incorporation into soil aggregates.Soil Tillage Research,109, 94–102.

    Mathieu J A, Hatte C, Balesdent J, Parent E. 2015. Deep soil carbon dynamics are driven more by soil type than by climate: A worldwide meta-analysis of radiocarbon profiles.Global Change Biology, 21, 4278–4292.

    Nelson D W, Sommers L E. 1996. Total carbon, organic carbon,and organic matter. In:Methods of Soil Analysis. American Society of Agronomy, USA. pp. 961–1010.

    Ouyang W, Qi S, Hao F, Wang X, Shan Y, Chen S. 2013. Impact of crop patterns and cultivation on carbon sequestration and global warming potential in an agricultural freeze zone.Ecological Modelling, 252, 228–237.

    Pan G, Li L, Wu L, Zheng X. 2003. Storage and sequestratio potential of topsoil organic carbon in China’s paddy soils.Global Change Biology, 10, 79–92.

    Pang L, Huang G B. 2006. Impact of different tillage method on changing of soil organic carbon in semi-arid area.Soil and Water Conservation, 20, 110–113.

    Piper C S. 1966.Soil and Plant Analysis. Inter Science Publishers, New York.

    Pittelkow C M, Liang X, Linquist B A, van Groenigen K J, Lee J,Lundy M E, van Gestel N, Six J, Venterea R T, van Kessel C. 2015. Productivity limits and potentials of the principles of conservation agriculture.Nature, 517, 365–368.

    Poeplau C, K?tterer T, Bolinder M A, B?rjesson G, Berti A,Lugato E. 2015. Low stabilization of aboveground crop residue carbon in sandy soils of Swedish long-term experiments.Geoderma, 237, 246–255.

    Powlson D S, Glendining M J, Coleman K, Whitmore A P.2011. Implications for soil properties of removing cereal straw: Results from long-term studies.Agronomy Journal,103, 279.

    Van Reeuwijk L P. 2002.Procedures for Soil Analysis. 6th ed. International Soil Reference and Information Centre,Wageningen.

    Song Z W, Zhu P, Gao H J, Peng C, Deng A X, Zheng C Y, Mannaf M A, Islam M N, Zhang W J. 2014. Effects of long-term fertilization on soil organic carbon content and aggregate composition under continuous maize cropping in Northeast China.Journal of Agricultural Science, 153,236–244.

    Srinivasarao C, Deshpande A N, Venkateswarlu B, Lal R,Singh A K, Kundu S, Vittal K P R, Mishra P K, Prasad J V N S, Mandal U K, Sharma K L. 2012. Grain yield and carbon sequestration potential of post monsoon sorghum cultivation in Vertisols in the semi arid tropics of central India.Geoderma, 175, 90–97.

    Sun B, Wang X Y, Wang F, Jiang Y J, Zhang Y X. 2013.Assessing the relative effects of geographic location and soil type on microbial communities associated with straw decomposition.Applied and Environmental Microbiology,79, 3327–3335.

    Sun Y, Huang S, Yu X, Zhang W. 2013. Stability and saturation of soil organic carbon in rice fields: Evidence from a longterm fertilization experiment in subtropical China.Journalof Soils and Sediments, 13, 1327–1334.

    Wang J, Wang X, Xu M, Feng G, Zhang W, Lu C A. 2015a.Crop yield and soil organic matter after long-term straw return to soil in China.Nutrient Cycling in Agroecosystems,102, 371–381.

    Wang J, Wang X, Xu M, Feng G, Zhang W, Yang X, Huang S.2015b. Contributions of wheat and maize residues to soil organic carbon under long-term rotation in north China.Scientific Reports, 5, 11409.

    Wang L, Qiu J, Tang H, Li H, Li C, Van Ranst E. 2008. Modelling soil organic carbon dynamics in the major agricultural regions of China.Geoderma, 147, 47–55.

    Wiesmeier M, Hübner R, K?gel-Knabner I. 2015. Stagnating crop yields: An over looked risk for the carbon balance of agricultural soils.Science of the Total Environment, 536,1045–1051.

    Wiesmeier M, Hübner R, Sp?rlein P, Geuss U, Hangen E,Reischl A, Schilling B, vov Lützow M, K?gel-Knabner I.2014. Carbon sequestration potential of soils in southeast Germay derived from stable soil organic carbon saturation.Global Chang Biology, 20, 653–665.

    Wiesmeier M, Poeplau C, Sierra C A, Maier H, Frühauf C,Hübner R, Kühnel A, Sp?rlein P, Geuss U, Hangen E,Schilling B, von Lützow M, K?gel-Knabner I. 2016. Projected loss of soil organic carbon in temperate agricultural soils in the 21st century: Effects of climate change and carbon input trends.Scientific Reports, 6, 1–17.

    Yan D, Wang D, Yang L. 2007. Long-term effect of chemical fertilizer, straw, and manure on labile organic matter fractions in a paddy soil.Biology and Fertility of Soils, 44,93–101.

    Yu G, Fang H, Gao L, Zhang W. 2006. Soil organic carbon budget and fertility variation of black soils in Northeast China.Ecological Research, 21, 855–867.

    Zhang J, Hu K, Li K, Zheng C, Li B. 2017. Simulating the effects of long-term discontinuous and continuous fertilization with straw return on crop yields and soil organic carbon dynamics using the DNDC model.Soil Tillage Research,165, 302–314.

    Zhang W, Wang X, Xu M, Huang S, Liu H, Peng C. 2010. soil organic carbon dynamics under long-term fertilizations in arable land of northern China.Biogeosciences, 7, 409–425.

    Zhang W, Xu M, Wang X, Huang Q, Nie J, Li Z, Li S, Hwang S W, Lee K B. 2012. Effects of organic amendments on soil carbon sequestration in paddy fields of subtropical China.Journal of Soils and Sediments, 12, 457–470.

    Zhang X, Sui Y, Song C. 2013. Degradation process of arable Mollisols.Soil Crop, 2, 1–6.

    Zheng L, Xie H, Zhang W, Zhang X. 2006. Effects of different ways of returning straw to the soils on soluble organic carbon.Ecological Research, 15, 80–83.

    猜你喜歡
    癌病流膠病櫻桃樹
    淺析黃瓜流膠病害與細(xì)菌性流膠病
    櫻桃樹屋
    櫻桃樹上的座位
    趣味(語文)(2021年4期)2021-08-05 07:52:04
    藍(lán)莓根癌病的發(fā)生與防治
    煙臺果樹(2021年3期)2021-07-21 10:34:42
    大棚櫻桃樹冬季修剪要點(diǎn)
    櫻桃引種過程中根癌病的發(fā)生情況調(diào)查
    河北果樹(2020年4期)2020-11-26 06:05:06
    武漢地區(qū)不同桃品種流膠病情況調(diào)查與評價(jià)
    落葉果樹(2020年5期)2020-10-22 07:32:12
    “櫻桃樹是我砍的”
    保護(hù)地黃瓜細(xì)菌性流膠病發(fā)生原因及防治對策
    甜櫻桃流膠病研究綜述
    煙臺果樹(2015年3期)2015-12-10 07:46:54
    久久中文字幕人妻熟女| 又黄又爽又免费观看的视频| 在线观看免费午夜福利视频| 日韩欧美一区二区三区在线观看| 欧美一级a爱片免费观看看 | 在线a可以看的网站| 美女黄网站色视频| 国产成人精品无人区| 特大巨黑吊av在线直播| 久久中文字幕人妻熟女| 日韩欧美国产在线观看| 午夜福利免费观看在线| 身体一侧抽搐| 韩国av一区二区三区四区| 精品日产1卡2卡| 18禁美女被吸乳视频| 欧美日韩黄片免| 日本一本二区三区精品| 国产精品亚洲av一区麻豆| 亚洲 国产 在线| 99精品在免费线老司机午夜| 亚洲欧美激情综合另类| 99国产综合亚洲精品| 日韩成人在线观看一区二区三区| 国产伦在线观看视频一区| 日韩欧美免费精品| 久久久国产欧美日韩av| 国语自产精品视频在线第100页| 国产片内射在线| 91国产中文字幕| 女生性感内裤真人,穿戴方法视频| 亚洲成人久久性| 日日摸夜夜添夜夜添小说| 国产激情欧美一区二区| 欧美乱色亚洲激情| 搡老熟女国产l中国老女人| 国产黄片美女视频| 18禁观看日本| 国产精品久久久av美女十八| 床上黄色一级片| 在线观看美女被高潮喷水网站 | 在线十欧美十亚洲十日本专区| 啦啦啦韩国在线观看视频| 国产成人av激情在线播放| www.自偷自拍.com| 欧美成人午夜精品| 91老司机精品| 精品一区二区三区四区五区乱码| 变态另类丝袜制服| 国产午夜福利久久久久久| 91麻豆av在线| 1024视频免费在线观看| 国产黄a三级三级三级人| 免费看a级黄色片| 亚洲最大成人中文| 成熟少妇高潮喷水视频| 桃红色精品国产亚洲av| 美女高潮喷水抽搐中文字幕| ponron亚洲| 一级毛片高清免费大全| 两性夫妻黄色片| 好男人电影高清在线观看| 国产探花在线观看一区二区| cao死你这个sao货| ponron亚洲| 亚洲色图av天堂| 老司机福利观看| 久久九九热精品免费| 午夜福利免费观看在线| 草草在线视频免费看| 一区二区三区高清视频在线| 成人高潮视频无遮挡免费网站| 亚洲avbb在线观看| 亚洲五月婷婷丁香| 亚洲性夜色夜夜综合| 精华霜和精华液先用哪个| 成人国产综合亚洲| 亚洲精品av麻豆狂野| 黄色片一级片一级黄色片| 99国产综合亚洲精品| 亚洲美女视频黄频| 两个人的视频大全免费| 午夜日韩欧美国产| 国产av一区在线观看免费| 我要搜黄色片| 国产精品,欧美在线| 50天的宝宝边吃奶边哭怎么回事| 制服诱惑二区| 啪啪无遮挡十八禁网站| 亚洲,欧美精品.| 精华霜和精华液先用哪个| 伊人久久大香线蕉亚洲五| 日本免费一区二区三区高清不卡| 在线观看66精品国产| 亚洲av片天天在线观看| 少妇的丰满在线观看| 中国美女看黄片| 国产三级黄色录像| 国产一区二区在线观看日韩 | 9191精品国产免费久久| 成人三级做爰电影| xxxwww97欧美| 亚洲成av人片免费观看| 国产精品av久久久久免费| av欧美777| 欧美+亚洲+日韩+国产| 他把我摸到了高潮在线观看| 白带黄色成豆腐渣| 啦啦啦韩国在线观看视频| 久久人妻av系列| 桃色一区二区三区在线观看| 又大又爽又粗| 日本 av在线| 国产激情偷乱视频一区二区| 午夜精品久久久久久毛片777| 亚洲一区中文字幕在线| 国产精品一及| 久久久久久亚洲精品国产蜜桃av| www.999成人在线观看| 1024香蕉在线观看| 久久精品国产清高在天天线| 国产又色又爽无遮挡免费看| 91字幕亚洲| 小说图片视频综合网站| 黄色成人免费大全| 777久久人妻少妇嫩草av网站| 国产午夜精品论理片| 国产探花在线观看一区二区| 国内久久婷婷六月综合欲色啪| 91麻豆av在线| 91麻豆av在线| 亚洲欧美精品综合久久99| 91麻豆av在线| 国产亚洲欧美98| 日本一二三区视频观看| 老鸭窝网址在线观看| 国产一区二区激情短视频| 丰满的人妻完整版| 午夜福利欧美成人| 国产精品久久久久久亚洲av鲁大| 12—13女人毛片做爰片一| 麻豆久久精品国产亚洲av| 亚洲午夜精品一区,二区,三区| 可以在线观看毛片的网站| 日本三级黄在线观看| 亚洲免费av在线视频| 亚洲色图 男人天堂 中文字幕| 国产成人精品无人区| 国产三级黄色录像| 天堂√8在线中文| 99久久精品热视频| 男女做爰动态图高潮gif福利片| 日本免费一区二区三区高清不卡| 我的老师免费观看完整版| 欧美日韩国产亚洲二区| 波多野结衣巨乳人妻| 午夜福利成人在线免费观看| 大型黄色视频在线免费观看| 午夜精品久久久久久毛片777| 性色av乱码一区二区三区2| 十八禁网站免费在线| 国产蜜桃级精品一区二区三区| 国产精品影院久久| 久久久久久免费高清国产稀缺| 国产精品免费视频内射| 国产精品98久久久久久宅男小说| 欧美日韩福利视频一区二区| 免费在线观看黄色视频的| 美女大奶头视频| 欧美乱色亚洲激情| 精品国产乱子伦一区二区三区| 国产精品永久免费网站| 国产激情久久老熟女| 人妻久久中文字幕网| 很黄的视频免费| 亚洲精品久久国产高清桃花| 久久精品成人免费网站| 最近最新免费中文字幕在线| 免费人成视频x8x8入口观看| 国产高清有码在线观看视频 | 18禁裸乳无遮挡免费网站照片| a级毛片在线看网站| 成人午夜高清在线视频| 少妇裸体淫交视频免费看高清 | 亚洲性夜色夜夜综合| 久久久久久久午夜电影| 国产精品爽爽va在线观看网站| 国产私拍福利视频在线观看| 欧美午夜高清在线| 国产精品香港三级国产av潘金莲| 精品电影一区二区在线| 亚洲欧美精品综合一区二区三区| 黄色毛片三级朝国网站| 亚洲在线自拍视频| 人妻久久中文字幕网| 日韩高清综合在线| 午夜精品在线福利| 免费看十八禁软件| 久久久久国内视频| 色精品久久人妻99蜜桃| 久久久久久久精品吃奶| 亚洲av熟女| 俄罗斯特黄特色一大片| 九九热线精品视视频播放| 九九热线精品视视频播放| 亚洲av日韩精品久久久久久密| 国产一区在线观看成人免费| 老熟妇仑乱视频hdxx| 国产爱豆传媒在线观看 | 国产午夜福利久久久久久| 这个男人来自地球电影免费观看| 国产91精品成人一区二区三区| 在线观看一区二区三区| 欧美黑人精品巨大| avwww免费| 亚洲美女视频黄频| 一区福利在线观看| 国产精品香港三级国产av潘金莲| 人人妻人人澡欧美一区二区| 午夜免费成人在线视频| 亚洲av成人不卡在线观看播放网| 久久久久久人人人人人| 18禁观看日本| 午夜福利在线在线| 国产精品,欧美在线| 欧美乱妇无乱码| 最近在线观看免费完整版| 欧美大码av| 黑人操中国人逼视频| 欧美又色又爽又黄视频| 精品久久久久久久末码| 免费在线观看亚洲国产| 高清毛片免费观看视频网站| 国产亚洲精品久久久久5区| 色播亚洲综合网| 免费看十八禁软件| 一本一本综合久久| 国产成人aa在线观看| 在线观看日韩欧美| 欧美日韩福利视频一区二区| 真人一进一出gif抽搐免费| 久久久国产成人免费| 老司机午夜十八禁免费视频| 中出人妻视频一区二区| 成熟少妇高潮喷水视频| 毛片女人毛片| 99热6这里只有精品| 午夜成年电影在线免费观看| 亚洲天堂国产精品一区在线| 色综合婷婷激情| 亚洲专区国产一区二区| 在线观看免费视频日本深夜| 每晚都被弄得嗷嗷叫到高潮| 无遮挡黄片免费观看| 国产精品av视频在线免费观看| 香蕉av资源在线| 90打野战视频偷拍视频| 亚洲精华国产精华精| 国产真实乱freesex| 成人国语在线视频| 蜜桃久久精品国产亚洲av| 50天的宝宝边吃奶边哭怎么回事| 免费观看精品视频网站| 欧美日韩国产亚洲二区| 免费无遮挡裸体视频| 久久婷婷成人综合色麻豆| 午夜影院日韩av| 婷婷六月久久综合丁香| АⅤ资源中文在线天堂| 久久精品国产亚洲av高清一级| 男人的好看免费观看在线视频 | 亚洲av中文字字幕乱码综合| 欧美激情久久久久久爽电影| 亚洲精品在线美女| 日韩成人在线观看一区二区三区| 色噜噜av男人的天堂激情| 黄色视频不卡| 久久亚洲真实| 国产精品美女特级片免费视频播放器 | 成年人黄色毛片网站| 久久久国产成人免费| 午夜福利成人在线免费观看| 脱女人内裤的视频| 天天一区二区日本电影三级| 亚洲精品中文字幕在线视频| 国产一区二区在线观看日韩 | 免费无遮挡裸体视频| 国产精品亚洲一级av第二区| 午夜视频精品福利| avwww免费| 天堂动漫精品| 9191精品国产免费久久| 日本a在线网址| 啪啪无遮挡十八禁网站| 亚洲精品中文字幕一二三四区| 男人的好看免费观看在线视频 | 久热爱精品视频在线9| 波多野结衣高清作品| 午夜亚洲福利在线播放| 男人的好看免费观看在线视频 | 99在线人妻在线中文字幕| 亚洲免费av在线视频| 久久久久免费精品人妻一区二区| 日本五十路高清| 88av欧美| 亚洲av电影在线进入| 日本免费a在线| 99精品久久久久人妻精品| 国产精品久久电影中文字幕| 亚洲国产欧美网| 国产一级毛片七仙女欲春2| 国产野战对白在线观看| 亚洲18禁久久av| 一边摸一边抽搐一进一小说| 国产日本99.免费观看| 国内精品久久久久精免费| av免费在线观看网站| 亚洲精品在线观看二区| 日韩三级视频一区二区三区| 亚洲一区高清亚洲精品| 欧美中文综合在线视频| 亚洲国产日韩欧美精品在线观看 | 精品国产乱码久久久久久男人| 黄色片一级片一级黄色片| 黄色a级毛片大全视频| 曰老女人黄片| 日本免费一区二区三区高清不卡| 亚洲片人在线观看| 69av精品久久久久久| 久久久久久亚洲精品国产蜜桃av| 中文字幕最新亚洲高清| 国产精品1区2区在线观看.| 色噜噜av男人的天堂激情| 久久人妻福利社区极品人妻图片| 精品欧美一区二区三区在线| 亚洲午夜精品一区,二区,三区| 在线视频色国产色| 日本精品一区二区三区蜜桃| 午夜福利免费观看在线| 亚洲色图 男人天堂 中文字幕| 蜜桃久久精品国产亚洲av| 亚洲国产精品合色在线| 国产成人系列免费观看| 国产精品日韩av在线免费观看| 后天国语完整版免费观看| 国内久久婷婷六月综合欲色啪| 成人永久免费在线观看视频| 天天躁夜夜躁狠狠躁躁| 日本精品一区二区三区蜜桃| 久久久久九九精品影院| 特大巨黑吊av在线直播| 真人做人爱边吃奶动态| 欧美一区二区精品小视频在线| 国产精品av视频在线免费观看| 丝袜美腿诱惑在线| 亚洲人成电影免费在线| 国产av一区在线观看免费| 国内精品一区二区在线观看| av天堂在线播放| 露出奶头的视频| 毛片女人毛片| 最近最新免费中文字幕在线| 毛片女人毛片| 精品欧美国产一区二区三| 成年女人毛片免费观看观看9| 俄罗斯特黄特色一大片| 国产精品,欧美在线| av中文乱码字幕在线| 色噜噜av男人的天堂激情| 欧美日韩亚洲综合一区二区三区_| 国产一区二区三区在线臀色熟女| 高清毛片免费观看视频网站| 三级毛片av免费| 午夜老司机福利片| 欧美色视频一区免费| 成人18禁高潮啪啪吃奶动态图| 中文字幕高清在线视频| 黄色a级毛片大全视频| 久久久久精品国产欧美久久久| 日韩国内少妇激情av| 老司机深夜福利视频在线观看| 91老司机精品| 一本精品99久久精品77| 久久久久久大精品| 巨乳人妻的诱惑在线观看| 亚洲国产精品合色在线| 欧美精品亚洲一区二区| 亚洲熟女毛片儿| 亚洲专区国产一区二区| 午夜a级毛片| 宅男免费午夜| 琪琪午夜伦伦电影理论片6080| 一个人免费在线观看电影 | 亚洲一区中文字幕在线| 欧美性长视频在线观看| 2021天堂中文幕一二区在线观| 一区福利在线观看| 久久精品影院6| 香蕉国产在线看| 两人在一起打扑克的视频| 狂野欧美激情性xxxx| 毛片女人毛片| 国产成人av教育| 级片在线观看| 国产乱人伦免费视频| 99久久99久久久精品蜜桃| 午夜视频精品福利| 欧美av亚洲av综合av国产av| 国产成年人精品一区二区| 欧美日韩乱码在线| 首页视频小说图片口味搜索| 成人18禁高潮啪啪吃奶动态图| 亚洲国产日韩欧美精品在线观看 | av福利片在线观看| 亚洲中文字幕一区二区三区有码在线看 | 亚洲国产看品久久| 天天躁狠狠躁夜夜躁狠狠躁| 免费在线观看完整版高清| 免费在线观看完整版高清| 91成年电影在线观看| cao死你这个sao货| 亚洲人与动物交配视频| 亚洲 欧美一区二区三区| 女人爽到高潮嗷嗷叫在线视频| 亚洲国产高清在线一区二区三| 人人妻人人澡欧美一区二区| 婷婷六月久久综合丁香| 99久久精品热视频| 久久性视频一级片| 国产成人欧美在线观看| 亚洲人成网站高清观看| 2021天堂中文幕一二区在线观| 亚洲 欧美 日韩 在线 免费| 欧美激情久久久久久爽电影| 黑人巨大精品欧美一区二区mp4| 欧美性长视频在线观看| 亚洲电影在线观看av| 村上凉子中文字幕在线| 欧美黑人欧美精品刺激| videosex国产| 夜夜爽天天搞| 很黄的视频免费| 91九色精品人成在线观看| 精品国产超薄肉色丝袜足j| 国产精品日韩av在线免费观看| 国产爱豆传媒在线观看 | 99久久久亚洲精品蜜臀av| 在线视频色国产色| 免费在线观看完整版高清| 免费看美女性在线毛片视频| 亚洲成av人片免费观看| 人人妻人人看人人澡| 国产一区二区三区视频了| 美女午夜性视频免费| 麻豆成人午夜福利视频| 两人在一起打扑克的视频| 99精品在免费线老司机午夜| 亚洲精品中文字幕在线视频| 91av网站免费观看| 国产成人av教育| 色综合婷婷激情| av在线播放免费不卡| 床上黄色一级片| 精品久久蜜臀av无| 国产精品一区二区三区四区免费观看 | av视频在线观看入口| 人成视频在线观看免费观看| 欧美一级a爱片免费观看看 | 美女午夜性视频免费| 成人手机av| 黄色a级毛片大全视频| 久久久久亚洲av毛片大全| 久久香蕉国产精品| 国产真实乱freesex| 一边摸一边做爽爽视频免费| 丁香欧美五月| 一夜夜www| 级片在线观看| 欧美成人午夜精品| 嫩草影视91久久| 老鸭窝网址在线观看| 亚洲国产精品久久男人天堂| 亚洲国产精品合色在线| 国产成年人精品一区二区| 高清毛片免费观看视频网站| 成人国语在线视频| 国产精品亚洲一级av第二区| 一区福利在线观看| 69av精品久久久久久| 日韩大尺度精品在线看网址| 亚洲国产高清在线一区二区三| 精品久久久久久,| 国内毛片毛片毛片毛片毛片| 亚洲欧美激情综合另类| 国产亚洲精品av在线| 日本免费一区二区三区高清不卡| 久久精品影院6| 国产av又大| 最近最新中文字幕大全电影3| 天天一区二区日本电影三级| 日韩欧美精品v在线| 色综合站精品国产| 一边摸一边抽搐一进一小说| 国内久久婷婷六月综合欲色啪| 搡老熟女国产l中国老女人| 妹子高潮喷水视频| 男女床上黄色一级片免费看| 青草久久国产| 国产亚洲精品一区二区www| svipshipincom国产片| 欧美乱色亚洲激情| 亚洲欧美日韩无卡精品| 久久中文字幕人妻熟女| 亚洲色图av天堂| 啦啦啦免费观看视频1| 久久中文字幕人妻熟女| 老司机靠b影院| 久久国产乱子伦精品免费另类| 亚洲性夜色夜夜综合| 好男人在线观看高清免费视频| 一级毛片高清免费大全| 国产三级中文精品| 色播亚洲综合网| 高清在线国产一区| 三级国产精品欧美在线观看 | 国产精品一区二区三区四区久久| 亚洲,欧美精品.| 国产麻豆成人av免费视频| 日韩大尺度精品在线看网址| 亚洲成人久久性| 十八禁人妻一区二区| 国产精品一区二区免费欧美| 9191精品国产免费久久| 日韩免费av在线播放| 亚洲av电影在线进入| 黑人欧美特级aaaaaa片| 国产精品一区二区精品视频观看| 欧美黄色片欧美黄色片| 老司机午夜福利在线观看视频| 日韩国内少妇激情av| 亚洲片人在线观看| xxxwww97欧美| 搡老熟女国产l中国老女人| 国产野战对白在线观看| 99在线视频只有这里精品首页| 国产探花在线观看一区二区| 在线观看免费视频日本深夜| 国产黄色小视频在线观看| 99久久精品国产亚洲精品| 老司机在亚洲福利影院| 嫩草影院精品99| 国产成人一区二区三区免费视频网站| 99热这里只有是精品50| 无遮挡黄片免费观看| 免费搜索国产男女视频| 亚洲av成人精品一区久久| 亚洲国产高清在线一区二区三| 少妇被粗大的猛进出69影院| 日本一二三区视频观看| 99国产精品一区二区三区| 成人三级黄色视频| 99riav亚洲国产免费| 特级一级黄色大片| 午夜福利欧美成人| 精品久久久久久久末码| 欧美精品啪啪一区二区三区| 国产男靠女视频免费网站| 18禁黄网站禁片免费观看直播| 岛国视频午夜一区免费看| 在线观看午夜福利视频| 99久久精品国产亚洲精品| 欧美久久黑人一区二区| 国产精品亚洲一级av第二区| 亚洲自拍偷在线| 男女视频在线观看网站免费 | av超薄肉色丝袜交足视频| 免费在线观看黄色视频的| 欧美国产日韩亚洲一区| 亚洲 欧美一区二区三区| 动漫黄色视频在线观看| 一a级毛片在线观看| 亚洲精品久久国产高清桃花| 国产视频内射| 淫妇啪啪啪对白视频| 男人舔女人的私密视频| 日韩三级视频一区二区三区| 给我免费播放毛片高清在线观看| 成熟少妇高潮喷水视频| 国产精品一区二区三区四区免费观看 | 91老司机精品| 日韩欧美 国产精品| 久久久久九九精品影院| 91成年电影在线观看| 亚洲人成伊人成综合网2020| 激情在线观看视频在线高清| 搡老妇女老女人老熟妇| 99热这里只有是精品50| 嫩草影视91久久| 久99久视频精品免费| 757午夜福利合集在线观看| 岛国视频午夜一区免费看| 非洲黑人性xxxx精品又粗又长| 午夜福利高清视频| 啪啪无遮挡十八禁网站| 99精品在免费线老司机午夜| 天堂√8在线中文| 精品国产乱子伦一区二区三区| 日本五十路高清| 久久精品成人免费网站| 日日摸夜夜添夜夜添小说| 亚洲激情在线av| 日韩高清综合在线| 在线观看舔阴道视频| 亚洲av日韩精品久久久久久密| 亚洲美女视频黄频|