Both conventional subsurface drip irrigation (CI) and alternate partial root zone subsurface drip irrigation (AI) are water-saving irrigation methods (IMs) used to solve agricultural water crises. The responses of alfalfa (Medicago sativa L.) actual evapotranspiration (ETa), and the relationship with hay yield to the two types of IMs have not been evaluated, which is crucial for the sustainable agricultural development of irrigation and water management. We investigated the effects of CI and AI and three irrigation volumes (IVs) (10, 20, and 30 mm) on alfalfa ETa, and their relationship with hay yield in 2017 and 2018. AI significantly reduced the alfalfa ETa by 10 and 17% under 20 and 30 mm irrigation volumes, respectively, in 2017 compared with CI. However, AI increased the ETa by 42 mm under 10 mm irrigation volume in 2017 and by 43 mm under a 30 mm irrigation volume in 2018. There was no significant effect on the alfalfa ETa between CI and AI under 10 and 20 mm IVs in 2018. The changes in alfalfa ETa could be explained by soil moisture and soil water storage dynamics. In addition, alfalfa ETa is also affected by irrigation volume and stand year. Over more, hay yield was linearly correlated with the alfalfa ETa, and the increase in the slope of the alfalfa–water production function of AI compared to the equivalent slope of CI was 180%. The increase is largely explained by the reproduce in hay yield. This study provides a better alfalfa–water production function irrigation method for promoting AI technology applied in farm production.

Utility-scale solar energy (solar parks) is rapidly expanding due to the growing demand for renewable energy sources. Despite the advantages of reducing greenhouse gas emissions, there is increasing debate regarding the ecological impacts of solar parks on native habitats. To address this issue, we used a solar park in alpine desert grasslands in the Qinghai-Tibet Plateau as a case study, to examine the effects of solar parks on various ecological components, including the microclimate, soil physicochemical properties, and plant and soil microbial communities. Furthermore, we evaluated the environmental impacts of solar parks based on the stability metrics of the aboveground and belowground communities. The research findings revealed that ecosystem stability metrics showed decoupled responses to solar parks. Aboveground community stability (ACS) declined sharply after the first year of solar park installation and stabilized thereafter. Belowground community stability (BCS) responded only subtly in the first year and increased with age. Multiple linear regression and random forest models showed that ACS was primarily regulated by plant and environmental properties, including plant diversity, plant functional traits, evaporation and soil water content. The structural equation model showed that BCS was directly influenced by microbial diversity and network complexity and indirectly affected by soil nutrient content and plant biomass. These findings indicate that solar parks would supply clean energy but have negative ecological impacts on native habitats via reduced ACS. Restoration practices promoting biodiversity and soil nutrient enrichment are recommended to enhance ecosystem stability. Furthermore, the distinct responses observed in ACS and BCS highlight the importance of considering multiple dimensions of ecosystem metrics for comprehensive evaluation of land-use change impacts.

Currently, the world is facing a serious agricultural water crisis, which also affects grassland areas. Alfalfa, a key perennial forage legume, consumes about 10% of China’s pastoral irrigation water. Reducing irrigation generally results in a loss of hay yield, but the effects on alfalfa quality and its relationship to water use are less clear. In this study, we explore alfalfa quality under different irrigation deficits and its relationship to water use in the Hexi Corridor of China. Alfalfa water use, quality yield (relative feeding value yield (RFVyield) and crude protein yield (CPyield)), and quality water use efficiency (relative feeding value water use efficiency (WUERFV) and crude protein water use efficiency (WUECP)) were measured in a field experiment. Alfalfa quality showed a negative correlation with the irrigation quota (the determination coefficient for relative feeding value was 0.375 and for crude protein was 0.289). There was a positive correlation between quality yield and irrigation quota (the determination coefficient for RFVyield was 0.570 and for CPyield was 0.631). The higher irrigation quota increased quality yield, which compensated for its negative effects on alfalfa quality. The mild and moderate water deficit treatments showed lower WUERFV than both the severe and no water deficit treatments. Moderate or mild water deficit is recommended to be used for one-year-old alfalfa treatment. No water deficit is beneficial to improve the quality water use efficiency of two-year-old alfalfa.

The drive towards carbon neutrality has prompted the worldwide expansion of utility-scale solar facilities. Previous studies have reported the positive effects of solar facilities’ installation on pasture productivity and biodiversity in arid regions. However, our understanding of how solar facilities influence a wide range of ecosystem functions simultaneously, and the relative contributions of soil microbial attributes, remains incomplete. To address this gap, we assessed the changes in ecosystem multifunctionality following solar facility installation in an alpine desert grassland in the Qinghai–Tibet plateau by measuring twenty-three ecosystem function indicators comprising primary production, the soil nutrient pool, carbon cycling, nitrogen cycling, phosphorus cycling and oxidation–reduction. Furthermore, we estimated the soil microbial diversity, microbial indicator taxa and microbial activity to identify the primary driving factors. The results showed that solar facilities had positive effects on ecosystem multifunctionality; the positive effect size was higher in the initial installation period (31.4%) than in the constant running period (3.5%). The enhancements in ecosystem multifunctionality were mainly due to enhanced nutrient cycling induced by the increased abundance of fungal indicator taxa and microbial activity. Moreover, the structural equation model revealed distinct regulatory paths between the two periods and a transition in the primary driving factors of ecosystem multifunctionality from microbial indicator taxa to microbial activity. In conclusion, our study demonstrates the positive influence of solar facilities on multiple ecosystem functions, emphasizing the critical role of soil microbial mechanisms in regulating ecosystem multifunctionality. These findings provide valuable insights into soil biota-driven processes that could inform strategies aimed at enhancing soil health and ecosystem functionality in arid grasslands under human-managed systems.

The effects of stomatal factors of plant leaves under partial root-zone drying (PRD) have been widely studied. However, the non-stomatal factors and the relationship between photosynthesis with soil moisture have not been explored. In this study, four treatments over-irrigation, full irrigation, moderate water deficit, and severe water deficit were investigated, aiming to evaluate the effects on the diurnal variation of alfalfa leaf photosynthesis under PRD and its relationship with stomatal and non-stomatal limitations, as well as soil moisture. The results showed that any levels of water deficit led to a decrease in the photosynthetic rate (Pn) of alfalfa leaves. Leaves under moderate and severe water deficit displayed a pronounced midday “photosynthetic lunch break,” while those under over- and full irrigation did not display this phenomenon. Before 11:30 a.m., the reduction in Pn was primarily due to stomatal limitations, as evidenced by reduced stomatal conductance (Gs) and decreased intercellular CO2 concentration (Ci). After 11:30 a.m., non-stomatal limitations became the dominant factor, with both Gs and transpiration rate (Tr) continuing to decrease, while Ci increased, indicating a shift in the limiting factors. Under PRD with moderate water deficit, alfalfa experienced both stomatal and non-stomatal limitations within a single day, leading to a hay yield reduction of 18.6%. Additionally, over-irrigation helped to maintain higher Pn and Tr, increasing alfalfa yield and thus improving water productivity by 33.1%. The correlation coefficients between soil moisture content at 10 cm depths with alfalfa leaf Pn, Tr, and Gs on the photosynthetic measurement day were 0.9864, 0.8571, and 0.8462, respectively. At 20 cm, the correlation coefficients were 0.8820, 0.6943, and 0.6951, respectively. The study concluded that both stomatal and non-stomatal mechanisms contributed to reduced alfalfa Pn in water deficit of PRD. Furthermore, shallow soil moisture also played a crucial role in influencing photosynthetic performance.

Water shortage seriously restricts the development of grassland agriculture in arid land and dramatically impacts alfalfa (Medicago sativa L.) quality content and hay yield. Reasonable irrigation methods have the potential to enhance the alfalfa quality content, hay yield, and thus quality yield. Whether partial root-zone drying subsurface drip irrigation (PRDSDI) improves the alfalfa quality yield, quality content, and hay yield is still unknown compared with conventional subsurface drip irrigation (CSDI). The effects of PRDSDI compared with that of CSDI and the interaction with irrigation volume (10 mm/week, 20 mm/week, and 30 mm/week) on the alfalfa quality yield were investigated in 2017–2018 and explained the change in quality yield with the alfalfa quality content and hay yield. Here, the results showed that PRDSDI did not increase the alfalfa quality yield in 2 years. PRDSDI significantly increased acid detergent fiber by 13.3% and 12.2% in 2018 with 10-mm and 20-mm irrigation volumes and neutral detergent fiber by 16.2%, 13.2%, and 12.6% in 2017 with 10-mm, 20-mm, and 30-mm irrigation volumes, respectively. PRDSDI significantly decreased the crude protein by 5.4% and 8.4% in 2018 with 10-mm and 20-mm irrigation volumes and relative feed value by 15.0% with 20-mm irrigation volume in 2017 and 9.8% with 10-mm irrigation volume in 2018, respectively. In addition, PRDSDI significantly increased the alfalfa average hay yield by 49.5% and 59.6% with 10-mm and 20-mm irrigation volumes in 2018, respectively. Our results provide a counterexample for PRDSDI to improve crop quality. Although there was no significant improvement in average quality yield by PRDSDI, the positive impact of average hay yield on quality yield outweighed the negative impact of quality content. Thus, it has the potential to improve quality yields. The novel findings regarding the effects of PRDSDI on quality yield are potentially favorable for the forage feed value in water-limited areas.

As a consequence of the tight linkages between plants, soil, and microorganisms, we hypothesized the variations in plant species would change soil and microbial stoichiometry. Here, we examined the plant leaf carbon (C):nitrogen (N):phosphorus (P) ratios of nine species coming from three plant functional groups (PFGs) in the riparian zones of Hulunbuir steppe during near-peak biomass. The soil C:N:P, microbial biomass carbon (MBC):microbial biomass nitrogen (MBN), and extracellular enzyme’s C:N:P were also assessed using the soils from each species. We found that plant tissue, soil nutrient, microbial, and enzyme activity stoichiometry significantly differed among different PFGs. Plant leaf and soil nutrient ratios tended to be similar (p > 0.05) between different species within the same PFGs. The variations in leaf C:N:P significantly correlated with the changes in soil C:N:P and MBC:MBN ratios. The homeostatic coefficients (H) < 1 suggested the relationships between plants and their resources C:N:P ratios might be non-homeostatic in the examined riparian zone. By assessing plant tissue and its soil nutrient stoichiometry, this study provided a perspective to understand the linkages of plant community, soil nutrient, and microbial characteristics.

This study aimed to investigate the effects of environmental disturbances on the stoichiometry characteristics of plants in degraded alpine meadows.To achieve this,a mowing experiment was conducted on an alpine meadow with three degradation levels[light degradation(LD),moderate degradation(MD),and severe degradation(SD)]in Shangri-La from 2018 to 2020.Subsequently,differences in plant carbon(C)content,nitrogen(N)content,phosphorous(P)content,C∶N∶P ratio,and N-P power function relationship among different mowing durations(0,1,2 a,respectively)were analysed.The results were as follows:(1)Except for the P content of Cyperaceae,plant C,N and P contents of the entire plant community,Gramineae and forbs did not vary among degradation levels(P＞0.05)during the mowing experiment.Plant C,N and P contents tended increase and then decrease with increasing mowing years,i.e.,these indices were the highest after 1 a of mowing(P＜0.05).(2)At the plant community and functional group levels,there was no significant difference in plant C∶N ratio and C∶P ratio among degradation levels(P＞0.05).From LD to SD,the N∶P ratio of the plant community,Cyperaceae and forbs tended to decrease slightly first and then increased(P＜0.05),while the N∶P ratio of Gramineae did not change significantly(P＞0.05).(3)The N∶P ratio and C∶P ratio showed a parabolic trend,while the C∶N ratio showed an inverse trend with the increasing of mowing duration.Before mowing(i.e.,mowing 0 a),the C∶P ratio and N∶P ratio of Cyperaceae were higher than those of forbs(P＜0.05)but did not vary from those of the plant community and Gramineae(P＞0.05).After mowing(i.e.,mowing 1 a or 2 a),the C∶P ratio and N∶P ratio of Cyperaceae were higher than those of the whole plant community,Gramineae,and forbs(P＜0.05).At each mowing duration,the C∶N ratio of plants did not vary among plant communities and functional groups(P＞0.05).(4)Mowing caused a stronger N-P power function relationship and a stable power exponent both at the plant community and functional group levels.And the N-P power exponent of Cyperaceae was less than 0.1,while those of the plant community,Gramineae and forbs remained stable at 0.19-0.22.In conclusion,this study found that plant stoichiometry remained stable across degradation levels but changed significantly with the prolongation of the mowing duration,which implies that different degraded alpine meadows in Northwest Yunnan may share common response mechanisms to mowing disturbance.

To clarify the different degrees of salinization how to influence the grassland plant community and carbon storage, we selected natural grassland, grassland-saline-alkaline transition zone, and saline-alkali land in Huihe Reserve for field investigation and sampling, and combined indoor analysis methods for testing and research. The results showed that with the intensification of grassland salinization, the composition of plant community structure tended to be simplified; the carbon storage of plants and ecosystems were all gradually decreasing. Besides, the topsoil organic carbon storage in grassland-saline-alkaline transition zone was the largest, followed by saline-alkali land, and the lowest was the natural grassland. The carbon storage of vegetation changed with different types, growth characteristics of aboveground plants, as well as soil physical and chemical properties. Also, the topsoil organic carbon storage was mainly affected by the interaction between aboveground plant types, soil moisture content, and different salinization degrees of grasslands. Turnover of the plants and change in soil pH can affect ecosystem carbon storage, especially soil pH can significantly affect topsoil organic carbon storage（P ＜ 0.05）. Therefore, the plant community and carbon storage in temperate meadow steppe were affected by the different salinization degrees of grasslands.

Both conventional subsurface drip irrigation (CI) and alternate partial root zone subsurface drip irrigation (AI) are water-saving irrigation methods (IMs) used to solve agricultural water crises. The responses of alfalfa (Medicago sativa) hay yield and actual evapotranspiration (ETa) under deficit irrigation (DI), and alfalfa–water production function to the two types of IMs have not been evaluated. We investigated the effects of two IMs (CI and AI) and three irrigation volumes (IVs) (severe DI: 10 mm/week, moderate DI: 20 mm/week, and full irrigation: 30 mm/week) on alfalfa hay yield, ETa, and alfalfa–water production function in 2017 and 2018. AI significantly increased alfalfa hay yield by 7–60% under DI in the two-year experiment and reduced the alfalfa ETa by 10% under moderate DI compared with CI in 2017. However, compared with CI, AI increased the ETa by 42 mm under severe DI in 2017. There was no significant effect on the alfalfa ETa between CI and AI under DI in 2018. The changes in hay yield and alfalfa ETa could be explained by soil moisture and soil water storage dynamics. In addition, hay yield was linearly correlated with the alfalfa ETa, and the increase in the slope of the alfalfa–water production function of AI compared to the equivalent slope of CI was 180%. This study provides a better hay yield IM under DI and alfalfa–water production function for promoting the AI method applied in irrigation management.

Alternate partial root-zone irrigation is a water-saving potential irrigation approach. In order to reveal the response of alfalfa（Medicago sativa L.） roots to the alternate partial root-zone irrigation, a comparative experiment between the alternate partial root-zone irrigation and the entire root-zone irrigation was carried out in National Field Scientific Observation and Research Station on Efficient Water Use in Oasis Agriculture in Wuwei of Gansu Province, along with the three irrigation water gradients: T1（180%～100% field capacity（FC））,T2（60%～80% FC）,T3（40%～60% FC）. The results showed that when 80%～100% FC irrigation was used by the alternate partial root-zone irrigation approach, the root neck diameter of alfalfa was smaller than that under the entire root-zone irrigation; and when 60%～80% FC and 40%～60% FC irrigation were used, the root neck diameter of alfalfa under the alternate partial root-zone irrigation was larger than that under root-zone irrigation. The number of root branches of alfalfa under the alternate partial root-zone irrigation were more than that under the entire root-zone irrigation, but the average root diameter of alfalfa was smaller than that under the entire root-zone irrigation. The aboveground and belowground biomass of alfalfa decreased with the decrease of irrigation gradients under the both two irrigation approaches. Under the same irrigation gradient, the belowground and aboveground biomass under the entire root-zone irrigation were higher than those under the alternate partial root-zone irrigation. The overall outcome of this study showed that the alternate partial root-zone irrigation approach had an important influence on the root growth and development of alfalfa.

Recent studies have shown distinct soil microbial assembly patterns across taxonomic types, habitat types and regions, but little is known about which factors play a dominant role in soil microbial communities. To bridge this gap, we compared the differences in microbial diversity and community composition across two taxonomic types (prokaryotes and fungi), two habitat types (Artemisia and Poaceae) and three geographic regions in the arid ecosystem of northwest China. To determine the main driving factors shaping the prokaryotic and fungal community assembly, we carried out diverse analyses including null model, partial mantel test and variance partitioning analysis etc. The findings suggested that the processes of community assembly were more diverse among taxonomic categories in comparison to habitats or geographical regions. The predominant driving factor of soil microbial community assembly in arid ecosystem was biotic interactions between microorganisms, followed by environmental filtering and dispersal limitation. Network vertex, positive cohesion and negative cohesion showed the most significant correlations with prokaryotic and fungal diversity and community dissimilarity. Salinity was the major environmental variable structuring the prokaryotic community. Although prokaryotic and fungal communities were jointly regulated by the three factors, the effects of biotic interactions and environmental variables (both are deterministic processes) on the community structure of prokaryotes were stronger than that of fungi. The null model revealed that prokaryotic community assembly was more deterministic, whereas fungal community assembly was structured by stochastic processes. Taken together, these findings unravel the predominant drivers governing microbial community assembly across taxonomic types, habitat types and geographic regions and highlight the impacts of biotic interactions on disentangling soil microbial assembly mechanisms.

The drive towards clean energy sources has prompted the worldwide construction of emerging photovoltaic solar parks. The intense Despite the advantages of lower pollutant and greenhouse gas emissions, the construction of solar parks (SP) is not without environmental and ecological consequences due to changes in land use and impacts on regional climate. Previous studies have reported that SP construction impacts microclimate, plant biomass, biodiversity, soil physicochemical properties, and soil microbial community structure. However, our understanding of how SP influences a wide range of ecosystem functions simultaneously remains incomplete. To address this gap, we assessed the changes in ecosystem multifunctionality (EMF) in SP habitats in arid ecosystem, by measuring twenty-three indicators related to ecosystem functions comprising primary production, soil nutrient pool, carbon cycling, nitrogen cycling, phosphorus cycling and oxidation-reduction. Furthermore, we identified the primary driving factors and regulatory mechanism of EMF in different periods since SP installation. The results showed that SP had positive effects on EMF indices, the positive effect size was higher in initial installation period (5.4%-149.0%) than in constant running period (0.4%-15.3%). The enhancement in EMF were mainly due to the enhanced nutrient cycling induced by increased abundance of fungal indicator taxa (Indicator) as well as microbial biomass and metabolic efficiency (MBM) according to the results of variance decomposition analysis and multiple linear regression. Moreover, the structural equation model revealed distinct regulatory mechanism between the two period, and a transition in the primary driving factors of EMF from Indicator to MBM. Together, our study reveals the different effect size of SP on EMF and changes in driving factor and regulatory mechanism of EMF during the different periods following SP installation. These findings complement the environmental impact analysis of SP construction.

Environmental factors are generally considered to be important factors affecting the release process of phosphorus (P) in sediments. However, little is known about the effect of temperature increased at first and then decreased with the season change on the P flux rate and flux amount at the sediment–water interface in the steppe wetlands. The effects of the temperature variation on P flux at the sediment–water interface in the steppe wetlands during the vegetation growing season under simulated wetland habitat were studied. The results showed that the release of P from sediments to overlying water was greatly affected by temperature changes. When the temperature rose, P was released from the sediment into the overlying water, while P was precipitated from the water into the sediment with the temperature dropped. During simulation period, the total P in water flux rates between sediment and overlying water (FP) was ranged from − 4.51 to 4.99 mg·m−2·day−1, while the dissolved reactive P in water flux rates between sediment and overlying water (FDP) was changed from − 5.37 to 5.14 mg·m−2·day−1. The FP and FDP were negatively correlated with the content of total P in water (WTP), dissolved reactive P in water (WDRP), pH of sediment (pH), and microbial biomass P (MBP), but increased with temperature (T), aluminum phosphate (Al.P), and occluded phosphate (Oc.P). The P flux rates were affected by temperature variation both directly and indirectly; the mechanism of how temperature influenced the fate of P in the wetland is still not clear. Therefore, the physicochemical properties and kinetic, thermodynamic, and microbiology characteristics should be combined together to clarify the mechanism in future research.

Solar park (SP) is rapidly growing throughout the planet due to the increasing demand for low-carbon energy, which represents a remarkable global land-use change with implications for the hosting ecosystems. Despite dozens of studies estimating the environmental impacts of SP based on local microclimate and vegetation, responses of soil microbial interactions and nutrient cycle potentials remain poorly understood. To bridge this gap, we investigated the diversity, community structure, complexity, and stability of co-occurrence network and soil enzyme activities of soil prokaryotes and fungi in habitats of ambient, the first, and sixth year since solar park establishment. Results revealed different response patterns of prokaryotes and fungi. SP led to significant differences in both prokaryotic and fungal community structures but only reduced prokaryotic alpha diversity significantly. Co-occurrence network analysis revealed a unimodal pattern of prokaryotic network features and more resistance of fungal networks to environmental variations. Microbial nitrogen and phosphorus cycle potentials were higher in SP and their variances were more explained by network features than by diversity and environmental characteristics. Our findings revealed for the first time the significant impacts of SP on soil prokaryotic and fungal stability and functional potentials, which provides a microbial insight for impact evaluation and evidence for the optimization of solar park management to maximize the delivery of ecosystem services from this growing land use.

The scarcity of water resources is becoming a global focus, and water conservation has become one of the most crucial service functions in the water security and sustainable development of ecosystems. Hulunbuir forest–steppe ecotone, as an important water conservation area in the northeastern provinces of China, plays an irreplaceable role in Northeastern China. However, the water yield and water conservation are rarely understood in the ecotone. In this study, the InVEST model was employed to analyze the spatiotemporal dynamics of water yield and water conservation from 2000 to 2020. Meanwhile, we explored the response of water conservation to climatic factors and human disturbance. The results demonstrated that water yield and water conservation presented a decreasing trend in the first decade and then increased. The land use transfer obvious from 2000 to 2010, and most vegetation types were converted into unused land. This transition intensified reduction of water conservation. The main factor affecting the water conservation was climate Precipitation had the greatest impact on water conservation. The findings of this study have great and important implications for regional sustainable water resource management and ecological protection policies and provide a convenient method for evaluating water conservation in other areas that are lacking climate, hydrology, and geological data.

草原是重要的自然资源和生态系统,具有十分重要的生态功能(如水源涵养、水分调节、水土保持、初级生产、气候调节和生物多样保护)和社会经济价值(如牧业生产、牧民生计维持、牧区文化传承等).科学保护、合理利用和有效恢复是草原资源和生态系统可持续管理的根本基础.2018年国家机构改革后草原主体功能从生产转向生态,草原在生态文明建设中的地位凸显.在新时代生态文明建设快速推进过程中,对标国家"山水林田湖草"生命共同体系统治理的总体战略,聚焦绿色发展和美丽中国建设的基本理念,提出基于地理分异和功能特征的草原分区方案,是推进草原资源高质量管理亟待解决的核心问题之一.利用文献调研、专家问卷调查和会议咨询等方法,构建以"生态保护优先、兼顾绿色发展"为主导思想的中国草原分区体系,提出生态地理单元分异原则、主体功能优先原则、产业布局协调性原则、历史传统相结合原则、行政边界完整性原则,提出了区、亚区和小区三级分区体系的主要指标、命名方式、功能判定及产业布局的厘定方法,将全国草原分为5个区(内蒙古高原草原区、西北山地盆地草原区、青藏高原草原区、东北华北平原山地丘陵草原区、南方山地丘陵草原区)、47个亚区、2899个小区,并给出了不同分区的主导生态功能及产业发展方向.分区结果具有综合性、协调性和时代性,可以为新时代草原生态文明建设和山水林田湖草系统治理提供科学支撑.

As a common measure for grassland restoration, the fence for prohibition of grazing is usually applied to the steppe in northern China. A study in Hulunbuir grassland showed the average litter mass in the steppes that enclosed for ten years can reach 70-550g/m2. The excessive accumulation of litter caused by long-term grazing prohibition can intercept more precipitation, which will reduce the water available to grassland plants and hinder the further recovery of plant communities. Therefore, the establishment of a reasonable litter interception model can help estimating the interception of steppes with different litter accumulation and provide some theoretical support for the formulation of fencing policies. Based on the model of litter interception rate change, we established a dynamic interception model of litter: I=Im(1−e−kt) (t: time;I: dynamic interception; Im: maximum interception; k: exponential coefficient of litter interception). After testing by an indoor simulated rainfall experiment, we found that this model has high accuracy (R2:0.908 – 0.992). The litter mass (LM) determines the maximum interception, and the rainfall intensity (RI) determines the speed of interception which reaches its maximum value. After the conversion of coefficients, we established a prediction model of litter interception based on LM and RI: I=(0.003LM+0.44)[1−e−(0.33RI+3.76)t],R2=0.86,P<0.001. The easily obtainable characteristics of LM and RI data make this model easy to apply.

作为"第三极"的青藏高原是全球中低纬度冰川最为发育的地区,被称为亚洲"水塔".但是由于气候变暖等原因,青藏高原冰川的季节性消融导致大量的冰川融水季节性流入下游草甸生态系统,对生态系统结构和功能产生影响.由于真菌群落的结构和功能对水分变化十分敏感,冰川融水的季节性变化必然将显著影响冰川末端高寒草甸土壤真菌群落结构和功能.但是关于冰川融水增加对冰川区高寒草甸土壤真菌群落的影响的认识还十分有限.2019年在青藏高原唐古拉山龙匣宰陇巴冰川末端通过双向移栽试验和高通量测序方法研究了冰川融水的增加和减少对土壤真菌群落的影响,发现融水增加显著改变了真菌群落组成和降低了香农多样性指数,同时增加了上层土壤植物病原型和腐生型真菌的相对含量.融水减少改变了真菌群落组成并增加了真菌的α多样性,但是对真菌的影响与融水增加过程并不具有对称性.由于真菌的重要生态功能,研究结果对于更好地认识气候变化和冰川消融情形下,青藏高原冰川区高寒草甸的生态系统过程和功能变化具有重要意义.