Research on early bilingual development has suggested that syntactic transfer in bilingual acquisition is dependent on patterns of dominance and properties of the dual input the child is exposed to. In a case study of a Hong Kong bilingual child we present evidence of transfer from Cantonese to English in three areas where the two languages contrast typologically: wh-in-situ interrogatives, null objects and prenominal relatives are observed at a period when Cantonese is dominant as measured by MLUw. Comparisons with monolingual development show both qualitative and quantitative differences attributable to transfer. Language dominance is seen as the major determinant of transfer, with input ambiguity playing a role in the domain of null objects. While two distinct and separate linguistic systems are simultaneously developing in the bilingual mind, the pervasiveness of transfer implies a high degree of interaction between them. The findings show that the bilingual subject in our case study has taken a different path from monolinguals toward the target.

No abstract

No abstract

The notion of language dominance is often defined in terms of proficiency. We distinguish dominance, as a property of the bilingual mind and a concept of language knowledge, from proficiency, as a concept of language use. We discuss ways in which language dominance may be assessed, with a focus on measures of mean length of utterance (MLU). Comparison of MLU in the child's 2 languages is subject to questions of comparability across languages. Using the Hong Kong Bilingual corpus of Cantonese-English children's development, we show how MLU differentials can be a viable measure of dominance that captures asymmetrical development where there is an imbalance between the child's 2 languages. The directionality of syntactic transfer goes primarily from the language with higher MLU value to the language with lower MLU value, and the MLU differential matches the pervasiveness of transfer effects, as in the case of null objects discussed here: The greater the differential, the more frequent the occurrence of null objects. Cantonese-dominant children with a larger MLU differential use null objects more frequently than those with a lower MLU differential. In our case studies, MLU differentials also matched with language preferences and silent periods but did not predict the directionality of code-mixing.

Findings from a longitudinal study of bilingual children acquiring Cantonese and English pose a challenge to the noun phrase accessibility hierarchy (NPAH; Keenan & Comrie, 1977), which predicts that object relatives should not be acquired before subject relatives. In the children's Cantonese, object relatives emerged earlier than or simultaneously with subject relatives, and in their English, prenominal relatives based on Cantonese emerged first, with object relatives followed by subject relatives. These findings are discussed in light of findings on the typology and acquisition of relative clauses (RCs) and the underlying processing motivations of the NPAH. Prenominal object relatives in the bilingual children's Cantonese and English have the same word order as main clauses and can be analyzed as internally headed RCs. The reconceptualization of RCs as attributive clauses (Comrie, 1998a, 1998b, 2002) is supported by children's early RCs lacking a strict grammatical relationship between the head noun and the predicate. Furthermore, as observed by Diessel and Tomasello (2000, 2005) for English, bilingual children's earliest RCs consist of isolated noun phrases (NPs). The early object relatives produced by bilingual children are therefore essentially NPs with the linear order of a main clause, resulting in a configuration that is conducive to early production.We thank Yasuhiro Shirai for organizing the workshop on second language acquisition of RCs at Cornell University in January 2006, where this paper was presented, as well as for his valuable comments on earlier versions of this paper. We thank all the participants at the workshop and two anonymous SSLA reviewers for their comments. Additional feedback offered by William O'Grady, Salikoko Mufwene, and John Whitman is greatly appreciated and hereby acknowledged. We thank our children for their contributions to this paper and all of the members of our research team who have contributed to this work—in particular, Uta Lam for her technical assistance. This research has been fully supported by the Research Grants Council of the Hong Kong Special Administrative Region, China (project Nos. HKU336/94H, CUHK4002/97H, CUHK4014/02H, and CUHK 4692/05H) and direct grants from the Chinese University of Hong Kong (01/02, 03/04).

No abstract

No abstract

The forests in northern Michigan will be affected directly and indirectly by changing climate during the 21st century. This assessment evaluates the vulnerability of forest ecosystems in the eastern Upper Peninsula and northern Lower Peninsula of Michigan under a range of future climates. We synthesized and summarized information on the contemporary landscape, provided information on past climate trends, and described a range of projected future climates. This information was used to parameterize and run multiple vegetation impact models, which provided a range of potential vegetative responses to climate. Finally, we brought these results before a multidisciplinary panel of scientists and land managers familiar with Michigan forests to assess ecosystem vulnerability through a formal consensus-based expert elicitation process. The summary of the contemporary landscape identifies major forest trends and stressors currently threatening forests in the region. Observed trends in climate over the past century reveal that precipitation increased in the area, particularly in summer and fall, and that daily maximum temperatures increased, particularly in winter. Projected climate trends for the next 100 years using downscaled global climate model data indicate a potential increase in mean annual temperature of 2.2 to 8.1 °F for the assessment area. Projections for precipitation indicate an increase in winter and spring precipitation, and summer and fall precipitation projections vary by scenario. We identified potential impacts on forests by incorporating these climate projections into three forest impact models (Tree Atlas, LANDIS-II, and PnET-CN). Model projections suggest that northern boreal species such as black spruce and paper birch may fare worse under future conditions, but other species such as American elm and white oak may benefit from projected changes in climate. Published literature on climate impacts related to wildfire, invasive species, and diseases also contributed to the overall determination of climate change vulnerability. We assessed vulnerability for nine forest communities in the assessment area, which were a combination of U.S. Department of Agriculture, Forest Service Forest Inventory and Analysis program forest types and Michigan Natural Features Inventory natural communities. The basic assessment was conducted through a formal elicitation process of 27 science and management experts from across the state, who considered vulnerability both in terms of potential impacts on a system and in terms of the system's adaptive capacity. Upland spruce-fir, jack pine, lowland conifers, and red pine-white pine forest communities were determined to be the most vulnerable. Barrens and lowland/riparian hardwood communities were perceived as less vulnerable to projected changes in climate. These projected changes in climate and the associated impacts and vulnerabilities will have important implications for economically valuable timber species, forest-dependent wildlife and plants, recreation, and long-range p...