Addressing the impact of canine distemper spreading on an isolated tiger population in northeast Asia.

The continuation of the isolated Amur tiger (Panthera tigris altaica) population living along the China-Russia border is facing serious challenges due to factors such as its small size (including 38 individuals) and canine distemper virus (CDV). We use a population viability analysis metamodel, which consists of a traditional individual-based demographic model linked to an epidemiological model, to assess options for controlling the impact of negative factors through domestic dog management in protected areas, increasing connectivity to the neighboring large population (including more than 400 individuals), and habitat expansion. Without intervention, under inbreeding depression of 3.

Contributions of distemper control and habitat expansion to the Amur leopard viability.

The Amur leopard (Panthera pardus orientalis) is a critically endangered top predator that struggles on the brink of extinction due to threats such as canine distemper virus (CDV), habitat loss, and inbreeding depression. Here we develop a viability analysis metamodel that combines a traditional individual-based demographic model with an epidemiological model to assess the benefits of alternative population management actions in response to multiple distinct threats. Our results showed an extinction risk of 10.

Satisfying meat demand while avoiding excess manure: Studying the trade-off in eastern regions of China with a nitrogen approach.

Due to the rising incomes and rapid urbanization, China is facing a challenge in producing more meat while avoiding excess manure. These objectives might be in contrast: if excess manure is avoided, meat self-sufficiency might not be met; in contrast, meeting meat self-sufficiency might cause severe excess manure. Our study (1) characterizes the eastern regions of China according to the deficiency/excess of manure nitrogen and meat production, and investigates their relationships with natural resources and social economic indicators; (2) analyzes how the trade-off changes with increasing proportion of chemical nitrogen substituted with manure nitrogen (PCSM).

Landscape consequences of aggregation rules for functional equivalence in compensatory mitigation programs.

Mitigation and offset programs designed to compensate for ecosystem function losses due to development must balance losses from affected ecosystems with gains in restored ecosystems. Aggregation rules applied to ecosystem functions to assess site equivalence are based on implicit assumptions about the substitutability of functions among sites and can profoundly influence the distribution of restored ecosystem functions on the landscape. We investigated the consequences of rules applied to the aggregation of ecosystem functions for wetland offsets in the Beaverhill watershed in Alberta, Canada.

Tree cover bimodality in savannas and forests emerging from the switching between two fire dynamics.

Moist savannas and tropical forests share the same climatic conditions and occur side by side. Experimental evidences show that the tree cover of these ecosystems exhibits a bimodal frequency distribution. This is considered as a proof of savanna-forest bistability, predicted by dynamic vegetation models based on non-linear differential equations.

Tree-grass co-existence in savanna: Interactions of rain and fire.

The mechanisms permitting the co-existence of tree and grass in savannas have been a source of contention for many years. The two main classes of explanations involve either competition for resources, or differential sensitivity to disturbances. Published models focus principally on one or the other of these mechanisms.