[Trade-off and synergy among ecosystem services and the influencing factors in the Ziwuling Region, Northwest China.] / å­åˆå²­åŒºç”Ÿæ€ç³»ç»ŸæœåŠ¡æƒè¡¡ä¸ŽååŒå˜åŒ–åŠå ¶å½±å“å› ç´ .

Ecosystem service (ES) bundle is a combination of various ecosystem services, serving as an indicator for the trade-off or synergy relationship among ecosystem services. Identifying the trade-off and synergy within ecosystem service bundles is helpful for realizing regional management and policymaking at the ES-bundle level. In this study, based on the InVEST model, the spatial composition, trade-off, and synergy of ES bundles, and their influencing factors were clarified using correlation analysis, cluster analysis, principal component analysis, and redundancy analysis. The results showed that the ESs in the Ziwuling Region (ZWLR) were generally improved from 2000 to 2017. The high-value area of soil conservation was concentrated in the northern part of the ZWLR, whereas other high-value areas of ESs were concentrated in the central and southern parts. According to the results of the cluster analysis, the ZWLR could be divided into four ES-bundles at pixel level. There was a strong tradeoff between water yield service and soil conservation in the core protected bundle, and a strong tradeoff between habitat quality, water yield service and food production in grain production bundle. The relationship between ESs in ecologi-cal transition bundle and ecologically fragile bundle was dominated by synergetic relationship. The ESs were affec-ted by both natural conditions and human activities. Vegetation cover, precipitation, and elevation had positive effects on the ESs, while temperature, the proportion of construction land, and population density had negative effects.

[Spatiotemporal variations of ecosystem service values and landscape ecological risk and their correlation in forest area of Loess Plateau, China:A case study of Ziwuling region.] / é»„åœŸé«˜åŽŸæž—åŒºç”Ÿæ€ç³»ç»ŸæœåŠ¡ä»·å€¼ä¸Žæ™¯è§‚ç”Ÿæ€é£Žé™©æ—¶ç©ºå˜åŒ–åŠå ¶å ³è”æ€§­­ä»¥å­åˆå²­åŒºä¸ºä¾‹.

Although the awareness of ecosystem services provided by natural landscape is increa-sing, few studies integrate ecosystem services value (ESV) into ecological risk management and its control. With Ziwuling region as an example, we carried out the gridding resampling of landscape pattern types in the forest area of Ziwuling region in 1980, 1990, 2000, 2010 and 2017. We quantified the ESV and landscape ecological risk and their spatiotemporal variations, based on the 2.5 km×2.5 km grid. The spatial correlation between the ESV and landscape ecological risk was examined. The results showed that the ESV decreased from the center to the outside of Ziwuling region, which increased from 12.345 to 12.633 billion yuan from 1980 to 2017. The landscape ecological risk increased from the center to the outside edge of Ziwuling region, indicating that the landscape ecological risk of Ziwuling region was reduced and the overall ecological situation was improved. There was a significant negative correlation and negative spatial correlation between ESV and landscape ecological risk in this area. The high value-low risk area was mainly located in Ziwu-ling forest area, while the ESV might be maintained in the future.

Effects of biodiversity and plant community composition on productivity in semiarid grasslands of Hulunbeir, Inner Mongolia, China.

Many recent studies have focused on the relationship between biodiversity and ecosystem functioning, such as investigations into the productivity of experimental plant communities. One of the central issues affecting the functioning of ecosystems is the diversity of resident species richness and the composition of the plant community. However, one challenge to experimental studies is that results from artificial ecosystems may have little value for predicting loss of diversity and function degradation in natural ecosystems. Thus, recent studies have focused more on investigations of natural ecosystems; these studies have found that species diversity and ecosystem productivity usually correlate with various abiotic factors including environmental effects, such as soil nutrition and precipitation, as well as anthropic activities, such as grazing and agricultural yield. In this study, we aimed to test the validity of biotic factors reported in experimental studies to be major factors affecting the productivity of ecosystems, and then to determine whether the relationship between biodiversity and ecosystem function is confounded by environmental factors. We investigated the effects of plant biodiversity and community composition on ecosystem function (productivity) in semiarid grassland in Inner Mongolia, China that contained three vegetation types: arid steppe, steppe, and meadow steppe. Our results show that both diversity and community composition significantly affect productivity and are better predictors of productivity than environmental factors, such as soil conditions. Our findings are consistent with the assumptions of niche complementarity. This study suggests that both biodiversity and community composition are important biotic factors in the functioning of ecosystems located in semiarid grasslands. In addition, environmental parameters, such as soil conditions influence productivity indirectly by affecting both biotic factors at the same time.

[Effects of vegetation restoration on soil microbial biomass carbon and nitrogen in hilly areas of Loess Plateau].

Aimed to explore the effects of different vegetations and of the years of vegetation restoration on soil microbial biomass carbon and nitrogen, a comparative study was conducted, with the 5 year old Robinia pseudoacacia, Hippophae reamnoide and Prunus armeniaca plantations and the 5, 15 and 25 years old R. pseudoacacia plantation in the Yangjuangou catchment of Yanan City of Shaanxi Province, a typical hilly area of the Loess Plateau, as test objects. The results showed that among the three 5-year old plantations, H. reamnoides plantation had the highest soil organic carbon (SOC) and total nitrogen (TN) contents, while R. pseudoacacia plantation had the highest soil microbial biomass carbon (MBC) (99.56 mg x kg(-1)) and nitrogen (MBN) (28.81 mg x kg(-1)). The MBC was in the order of R. pseudoacacia > H. reamnoides > P. armeniaca, and that of MBN was of R. pseudoacacia > P. armeniaca > H. reamnoides. The MBC/SOC was in the order of R. pseudoacacia > H. reamnoides > P. armeniaca, and that of MBN/TN was of R. pseudoacacia > P. armeniaca > H. reamnoides, with the differences being significant (P < 0.05). With the increasing years of vegetation restoration, the soil pH in R. pseudoacacia plantation decreased, while the SOC, TN, electricity conductance (EC), MBC, and MBN all had an increasing trend, which illustrated that in the hilly area of Loess Plateau, planting R. pseudoacacia was more beneficial to the increase of soil MBC and MBN, and, with the increasing years of this planting, soil MBC, MBN, SOC and TN tended to be increasing.