Global warming has contributed to the extension of the growing season in North Hemisphere. In this paper, we investigated the spatial characteristics of the date of the start of the season (SOS), the date of the end of the season (EOS) and the length of the season (LOS) and their change trends from 1982 to 2015 in Northeast China. Our results showed that there was a significant advance of SOS and a significant delay of EOS, especially in the north part of Northeast China. For the average change slope of EOS in the study area, the delay trend was 0.25 d/y, which was more obvious than the advance trend of −0.13 d/y from the SOS. In particular, the LOS of deciduous needleleaf forest (DNF) and grassland increased with a trend of 0.63 d/y and 0.66 d/y from 1982 to 2015, indicating the growth season increased 21.42 and 22.44 days in a 34-year period, respectively. However, few negative signals were detected nearby Hulun Lake, suggesting that the continuous climate warming in the future may bring no longer growing periods for the grass in the semiarid areas as the drought caused by climate warming may limit the vegetation growth.

The black soil region of Northeast China has suffered from severe soil erosion by water. Hillslope and gully erosion are the main erosion types. The objective of this research was to integrate the assessment of hillslope and gully erosion and explore spatial coupling relations between them in the Mushi River sub-catchment using geographical conditions monitoring (GCM) including remote sensing (RS) and geographic information system (GIS) techniques. The revised universal soil loss equation (RUSLE) model and visual satellite image interpretation were used to evaluate hillslope and gully erosion, respectively. The results showed that (1) the study area as a whole had slight erosion due to rill and sheet erosion, but suffered more serious gully erosion, which mainly occurs in cultivated land; (2) GCM contributed to the overall improvement of soil erosion assessment, but the RUSLE model likely overestimates the erosion rate in dry land; (3) the hillslope and gully erosion were stronger on sunny slopes than on shady slopes, and mainly occurred at middle elevations. When the slope was greater than 15 degrees, the slope was not the main factor restricting the erosion, while at steeper slopes, the dominant forest land significantly reduced the soil loss; (4) trends of gully erosion intensity and density were not consistent with the change in soil erosion intensity. To our knowledge, this study was one of the first that attempted to integrate gully erosion and hillslope erosion on a watershed scale. The findings of this study promote a better understanding of the spatial coupling relationships between hillslope and gully erosion and similarly indicate that GCM, RS, and GIS can be used efficiently in the hilly black soil region of Northeast China to assess hillslope and gully erosion.

The warming or cooling effects on regional climate in response to early land use change may be strengthened, weakened, or eliminated by the same or opposite effect in the subsequent land use/management period. Taking the Sanjiang Plain in China as our study area, this paper analyzed the surface temperature change due to land use/land management changes from the mid‐1950s to 2015, based on the land surface temperature response model and the observation minus reanalysis (OMR) method using remote sensing data, meteorological observation data, and reanalysis data. Results revealed a magnitude of monthly mean land surface warming up to 1.31 °C due to the land use change from wetland to rain‐fed farmland and a cooling effect of −1.32 °C caused by the land management change from rain‐fed farmland to paddy fields during the growing season. The trends were confirmed using OMR method. Land surface temperature change based on remote sensing data was divided into radiative and nonradiative forcing. The nonradiative processes play a dominant role in regulating the local surface temperature. The monthly mean temperature differences in response to land use changes differ greatly during the growing season. The temperature difference was greater in May and June (spring) than in July and August (summer). Our study shows that the land use impact on regional climate could be switched dramatically, and it would be basically consistent with the impact of natural wetlands before reclamation in our study area right now, which provides important information for mitigating and adapting to global climate change at regional scale.

Earlier leaf-out enhances spring moisture exchange between land and atmosphere. However, its impact on precipitation intensity remains unclear, hampering dynamic monitoring on water erosion. Here we combined remote sensing, reanalysis data, and coupled land-atmosphere model to address this knowledge gap. Results observed an increasing trend in spring precipitation accompanied by earlier leaf-out across temperate China. The simulations isolated the phenological impacts and attributed it to the enhancement of nonerosive precipitation. The mid-temperate semi-humid region exhibited the largest increase (3.03 ± 3.66 mm) in response to 14-days leaf-out advancement. Conversely, erosive precipitation declined in sparsely vegetated areas (<50% cover), sharpening the heterogeneity of moisture gradient. Elevated convective available potential energy promoted more frequent precipitation, inhibiting the deep moisture accumulation required for erosive downpours. Simulated erosive precipitation also declined in temperate summer and autumn. Findings highlight vegetation’s role in precipitation redistribution beyond surface interception, requiring conservation planning to consider bidirectional vegetation-climate feedback.

Wetlands are recognized for their climate mitigation potential through carbon storage and local cooling effects. Yet, the spatial variability of how wetland vegetation influences local climates via biogeophysical process remains poorly understood. Here, we examine the impacts of wetland vegetation changes on land surface temperature (LST) across the Amur River Basin using satellite data and model simulations. Our results reveal significant cooling effects associated with increased wetland vegetation, with the strongest cooling observed in semi‐arid areas (−1.12°C m² m⁻²), compared to semi‐humid (−0.46°C m² m⁻²) and humid zones (−0.45°C m² m⁻²). Decoupling biogeophysical pathways reveals that atmospheric feedback, aerodynamic resistance and surface resistance accounted for 44.4%, 41.5%, and 13.3%, respectively, of the diagnosed LST sensitivities to leaf area index in semi‐arid regions, whereas aerodynamic resistance and atmospheric feedback contributed 75.2% and 23.8%, respectively, in humid regions. Our findings suggest wetland vegetation restoration, particularly in semi‐arid regions, could provide substantial climate mitigation benefits through biogeophysical process.

The irrigated paddy fields have expanded greatly at semi-arid western Jilin province of China in recent over ten years, the sources of which are rain-fed cornfields, swamp meadow and saline alkali land mainly. Based on regional land use data, remote sensing data and meteorological data, this paper evaluates the land surface temperature changes response to land surface biophysical processes changes resulting from land use change (LUC), and dissociates the effect of radiative change (albedo) and non-radiative change (evapotranspiration and turbulent process) quantitatively using the energy redistribution factor. The results show that, the total land surface temperature changes based on energy redistribution factor are consistent with that based on remote sensing data on the whole, which have significant and different seasonal variations for agriculture adjustment of rain-fed cornfields to irrigated paddy fields and nature land reclamation. Generally, the largest Land surface temperature changes (ΔTs) are most pronounced in May and June for agriculture adjustment of rain-fed cornfields to irrigated paddy fields, which is −1.85 K averagely. Notable decline of albedo from saline alkali land to irrigated paddy fields in April to June greatly counteracts the cooling effect of non-radiative processes changes, while the largest ΔTs is found of −2. 54 K in dry summer months of July and August. For swamp meadows to irrigated paddy fields, non-radiative process is strengthened from June to September, the cooling effect of which is −1.69 K averagely. This study provides a case reference of local temperature change and obvious changes of land surface non-radiative terms at semi-arid area for adjustment of agricultural activities and land use changes.