Assessment of Future Climate and Land Use Change Impacts on Hydrological Behavior of Dam Watershed Using SWAT-K Model

AbstractChanges in land use and climate are the main drivers of change in soil organic matter contents. We investigated the impact of the largest policy-induced land conversion to arable land, the Virgin Lands Campaign (VLC), from 1954 to 1963, of the massive cropland abandonment after 1990 and of climate change on soil organic carbon (SOC) stocks in steppes of Russia and Kazakhstan. We simulated carbon budgets from the pre-VLC period (1900) until 2100 using a dynamic vegetation model to assess the impacts of observed land-use change as well as future climate and land-use change scenarios. The simulations suggest for the entire VLC region (266 million hectares) that the historic cropland expansion resulted in emissions of 1.6⋅ 1015 g (= 1.6 Pg) carbon between 1950 and 1965 compared to 0.6 Pg in a scenario without the expansion. From 1990 to 2100, climate change alone is projected to cause emissions of about 1.8 (± 1.1) Pg carbon. Hypothetical recultivation of the cropland that has been abandoned after the fall of the Soviet Union until 2050 may cause emissions of 3.5 (± 0.9) Pg carbon until 2100, whereas the abandonment of all cropland until 2050 would lead to sequestration of 1.8 (± 1.2) Pg carbon. For the climate scenarios based on SRES (Special Report on Emission Scenarios) emission pathways, SOC declined only moderately for constant land use but substantially with further cropland expansion. The variation of SOC in response to the climate scenarios was smaller than that in response to the land-use scenarios. This suggests that the effects of land-use change on SOC dynamics may become as relevant as those of future climate change in the Eurasian steppes.

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Future climate and land use instability can negate the benefits of protected areas

10.21203/rs.3.rs-270966/v1 ◽

2021 ◽

Author(s):

Ernest Asamoah ◽

Linda Beaumont ◽

Joesph M Maina

Keyword(s):

Land Use ◽

Land Use Change ◽

Protected Areas ◽

Multiple Scales ◽

Future Climate ◽

Spatially Adaptive ◽

Climate Stress ◽

Potential Benefits ◽

High Conservation ◽

Climate Velocity

Abstract Expanding protected area networks and enhancing their capacities is currently one avenue at the forefront of efforts to conserve and restore global biodiversity. Climate and habitat loss resulting from land use interact synergistically to undermine the potential benefits of protected areas (PAs). Targeting conservation, adaptation and mitigation efforts requires an understanding of patterns of climate and land-use change within the current arrangement of PAs, and how these might change in the future. In this paper, we provide this understanding using predicted rates of temporal and spatial displacement of future climate and land use globally and within PAs. We show that ~ 47% of the world’s PAs—10.6% of which are under restrictive management—are located in regions that will likely experience both climate stress and land-use instability by 2050. The vast majority of these PAs are also distributed across moist biomes and in high conservation value regions, and fall into less-restrictive management categories. The differential impacts of combined land use and climate velocity across protected biomes indicate that climate and land-use change may have fundamentally different ecological and management consequences at multiple scales. Taken together, our findings can inform spatially adaptive natural resource management and actions to achieve sustainable development and biodiversity goals.

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