Abstract:The tradeoffs and synergies of ecosystem services are widely discussed and recognized. However, explicit information for understanding and managing the complex relationships of multiple ecosystem services at regional scales is still lacking, which often leads to the degradation of important ecosystem services due to one ecosystem service being enhanced over another. We assessed the biodiversity and the production of nine ESs (ecosystem services) across 779 counties in the Yangtze River Basin, the largest basin in China. Then, we mapped the distribution of ES for each county and used correlations and "partitioning around medoids" clustering analysis to assess the existence of ES bundles. We found five distinct types of bundles of ecosystem services spatially agglomerated in the landscape, which could be mainly explained by land use, slope and altitude gradients. Our results also show landscape-scale tradeoffs between provisioning and almost all regulating services (and biodiversity), and synergies among almost all regulating services (and biodiversity). Mapping ecosystem service bundles can identify areas in a landscape where ecosystem management has produced exceptionally desirable or undesirable sets of ecosystem services, and can also provide explicit, tailored information on landscape planning for ecosystem service conservation and the design of payment policies for ecosystem services within diverse landscapes at watershed scales.

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Tandemly arrayed genes (TAGs) account for about one-third of the duplicated genes in eukaryotic genomes. They provide raw genetic material for biological evolution, and play important roles in genome evolution. The 22-kDa prolamin genes in cereal genomes represent typical TAG organization, and provide the good material to investigate gene amplification of TAGs in closely related grass genomes. Here, we isolated and sequenced the Coix 22-kDa prolamin (coixin) gene cluster (283 kb), and carried out a comparative analysis with orthologous 22-kDa prolamin gene clusters from maize and sorghum. The 22-kDa prolamin gene clusters descended from orthologous ancestor genes, but underwent independent gene amplification paths after the separation of these species, therefore varied dramatically in sequence and organization. Our analysis indicated that the gene amplification model of 22-kDa prolamin gene clusters can be divided into three major stages. In the first stage, rare gene duplications occurred from the ancestor gene copy accidentally. In the second stage, rounds of gene amplification occurred by unequal crossing over to form tandem gene array(s). In the third stage, gene array was further diverged by other genomic activities, such as transposon insertions, segmental rearrangements, etc. Unlike their highly conserved sequences, the amplified 22-kDa prolamin genes diverged rapidly at their expression capacities and expression levels. Such processes had no apparent correlation to age or order of amplified genes within TAG cluster, suggesting a fast evolving nature of TAGs after gene amplification. These results provided insights into the amplification and evolution of TAG families in grasses.

Ecological compensation is a crucial policy instrument that realigns the benefits of stakeholders to the ecosystem service provision. However, the spatial disconnections between locations where ecosystem services produced and used are common. The supply and demand for ecosystem services are calculated to reflect the status of the districts or counties based on ecosystem service flows. The replacement cost methods provide necessary technical supports for the calculation of compensation funds. The realigning of compensation funds between service-benefiting areas and service-providing areas not only identifies the beneficiaries and suppliers but also realizes the connection between them, which may be a feasible methodology. Fuzhou City is the study area, and two ecosystem services of water conservation and soil retention were taken into consideration. The prioritized development zone, Linchuan, and the key agricultural production zones paid ecological compensation funds. Linchuan paid the highest, 5.76 billion yuan. The key ecological function zones and the key agricultural production zones received the ecological compensation funds, of which Yihuang obtained the highest, 1.66 billion yuan. The realigning of compensation funds between the service benefiting and providing areas addresses the trade-offs between ecosystem services, social development, and ecosystem protection. Embedding the ecosystem service flows into the ecological compensation mechanism can most truly realize the value of ecosystem services, achieve the “beneficiary pays” principle, and be conducive to regional sustainable development.

Landscape change is an important aspect of coastal ecological conservation and has an essential influence on the sustainable development of the coastal economy. With remoting-sensing (RS) images between 2000, 2005, 2010, and 2015, using geographic information system (GIS) technologies, we examined ecosystem spatial changes in the Bohai coastal zone. Results showed that wetlands, mainly constituted by reservoirs/ponds, were the dominant landscape types. The urban ecosystem has the largest area increment and the fastest growth rate from 2000 to 2015. The quantification of landscape metrics revealed that spatial patterns have changed significantly, and the change direction of these ecosystems had moved toward increased heterogeneity and fragmentation. In addition, natural and socio-economic data were used to analyze the major driving forces triggering ecosystem spatial changes through redundancy analysis (RDA). The results revealed that the output of aquatic products (AQ) and population (Pop) were the main factors related to wetland ecosystem change. Pop and gross domestic product per capita (GDPpc) were closely related to the urban ecosystem change. Annual mean temperature (ATm), crop acreage (CA), and grain yield (GY) had positive correlations with the agriculture ecosystem changes.

The relative contributions of different factors to the variation in surface runoff have been broadly quantified. However, little attention has been paid to how these relative contributions have changed over time. We analyzed the changes in surface runoff during 1980-2010 in six subbasins in the mountainous region of the Haihe River Basin, one of the most serious water shortage regions in China, and identified the changes in the relative contributions of climate (precipitation and temperature) and land-use to surface runoff decrease. There was a decreasing tendency in surface runoff in all subbasins, four of which had an abrupt change point around 1998. Comparing the relative contributions before and after 1998 in the four subbasins, the average influence of climate was found to decline dramatically from 67.1% to 30.5%, while that of land-use increased from 23.9% to 69.5% mainly due to the increase of forest area. Our results revealed that the primary environmental factor responsible for runoff variations was not constant, and an alternation may accentuate the impact and stimulate an abrupt change of runoff in semiarid and semihumid mountainous regions. This will help in taking tracking measures to deal with the complex water resource challenges according to different driving factors.

Maintaining or increasing water retention in ecosystems (WRE) can reduce floods and increase water resource provision. However, few studies have taken the effect of the spatial information of vegetation structure into consideration when assessing the effects of land use/land cover (LULC) change on WRE. In this study, we integrated the remotely sensed leaf area index (LAI) into the ecosystem process-based Biome-BGC model to analyse the impact of LULC change on the WRE of Beijing between 2000 and 2015. Our results show that the volume of WRE increased by approximately 8.58 million m3 in 2015 as compared with 2000. The volume of WRE in forests increased by approximately 26.74 million m3, while urbanization, cropland expansion and deforestation caused the volume of WRE to decline by 11.96 million m3, 5.86 million m3 and 3.20 million m3, respectively. The increased WRE contributed by unchanged forests (14.46 million m3) was much greater than that of new-planted forests (12.28 million m3), but the increase in WRE capacity per unit area in new-planted forests (124.69 ± 14.30 m3/ha) was almost tenfold greater than that of unchanged forests (15.60 ± 7.85 m3/ha). The greater increase in WRE capacity in increased forests than that of unchanged forests was mostly due to the fact that the higher LAI in unchanged forests induced more evapotranspiration to exhaust more water. Meanwhile, the inverted U-shape relationship that existed between the forest LAI and WRE implied that continued increased LAI in forests probably caused the WRE decline. This study demonstrates that integrating remotely sensed LAI with the Biome-BGC model is feasible for capturing the impact of LULC change with the spatial information of vegetation structure on WRE and reduces uncertainty.